G°V — * °' , ' o < >n..; . yy^ s y ,.. * o><;*- •$ . : /4 tap" A/oW» : ^ V \ %^P* <^\° United States Environmental Protection Agency Office of Air Quality Planning And Standards Research Triangle Park, NC 27711 EPA-454/R-98-013 June 1998 O EPA LOCATING AND ESTIMATING AIR EMISSIONS FROM SOURCES OF ARSENIC AND ARSENIC COMPOUNDS X\^" u '< of co v' AOH <1 * ] q /Oc-03 a/.w-j? 99 - /5 %£>&4 7.8 Process Heaters . 7_35 7.9 Cotton Production and Ginning. 7 _ 3 g 8.0 SOURCE TEST PROCEDURES . g _j 8.1 Ambient Air Sampling Methods . 09 vi TABLE OF CONTENTS, continued Section Page 8.1.1 Methodology for the Determination of Suspended Particulate Matter in the Atmosphere (High-Volume Method) and Modified Methodology for the Determination of Lead in Suspended Particulate Matter Collected from Ambient Air .8-2 8.1.2 NIOSH Method 7300 - Methodology for the Determination of Elements by Inductively Coupled Plasma (ICP) ..8-4 8.1.3 NIOSH Method 7900 - Methodology for the Determination of Arsenic and Compounds, as Arsenic, using Direct-Aspiration (Flame) Atomic Absorption Spectroscopy (AAS).8-5 8.1.4 NIOSH Method 7901 - Methodology for the Determination of Arsenic Trioxide, as Arsenic, by Graphite Furnace Atomic Absorption (GFAA).8-5 8.1.5 NIOSH Method 5022 - Methodology for the Determination of Organo-Arsenic Compounds by Ion Chromatography (IC)/Graphite Furnace Atomic Absorption (GFAA) .8-6 8.2 Stationary Source Sampling Methods .8-6 8.2.1 EPA Method 29 - Determination of Metals Emissions from Stationary Sources.8-7 8.2.2 EPA Method 108 - Methodology for the Determination of Particulate and Gaseous Arsenic Emissions .8-9 8.2.3 EPA BEF Method Section 3.0 - Methodology for the Determination of Metals Emissions in Exhaust Gases from Hazardous Waste Incineration and Similar Combustion Processes.8-9 8.2.4 CARB Method 423 - Methodology for the Determination of Particulate and Gaseous Inorganic Arsenic Emissions from Stationary Sources.8-11 8.2.5 CARB Draft Method 436 - Determination of Multiple Metals Emissions from Stationary Sources.8-11 8.3 Analytical Techniques For The Measurement Of Arsenic.8-11 8.3.1 Direct Aspiration (Flame) Atomic Absorption Spectroscopy (AAS) .8-12 8.3.2 Graphite Furnace Atomic Absorption (GFAA) Spectroscopy.8-12 8.3.3 Inductively Coupled Plasma (ICP) Atomic Emission Spectroscopy .. 8-13 8.3.4 Hydride Generation Atomic Absorption (HGAA) Spectroscopy .... 8-13 8.3.5 Ion Chromatography (IC)/GFAA.8-14 APPENDICES Appendix A - Emission Factor Summary Table. A-l Vll LIST OF TABLES Table Page 3-1 Physical Properties of Arsenic.3-2 3-2 Important Arsenic-Bearing Minerals.3-3 3-3 Common Arsenic Compounds.3-4 3-4 Physical Properties of Arsenic Halides .3-6 3-5 Physical Properties of Common Arsenic Sulfides.3-9 3-6 Organic Arsenic Compounds.3-11 3- 7 U.S. Imports for Consumption of Arsenicals, by Country.3-18 4- 1 Arsenic Emission Factors for Wood Waste-Fired Utility Boilers.4-18 4-2 Arsenic Emission Factors for Wood Waste-Fired Industrial Boilers .... . : . . 4-19 4-3 Arsenic Emission Factors for Wood Waste-Fired Commercial/Institutional Boilers . 4-21 4-4 Arsenic Emission Factors for Coal-Fired Utility Boilers.4-23 4-5 Arsenic Emission Factors for Coal-Fired Industrial Boilers .4-25 4-6 Arsenic Emission Factors for Coal-Fired Commercial/Institutional Boilers.4-27 4-7 Arsenic Emission Factors for Oil-Fired Utility Boilers.4-28 4-8 Arsenic Emission Factors for Oil-Fired Industrial Boilers . 4-29 4-9 Arsenic Emission Factors for Oil-Fired Commercial/Institutional Boilers.4-30 4-10 Arsenic Emission Factors for Waste Oil-Fired Industrial Boilers.4-31 4-11 Arsenic Emission Factors for Waste Oil-Fired Commercial/Institutional Boilers .. . 4-32 4-12 Arsenic Emission Factors for Solid Waste-Fired Utility Boilers. 4-34 4-13 Arsenic Emission Factors for Hazardous Waste Incineration.4-44 4-14 Arsenic Emission Factors for Municipal Waste Combustion Sources .4-53 vm LIST OF TABLES, continued Table Page 4-15 Summary of Geographical Distribution of MWC Facilities (1997) . 4-57 4-16 Arsenic Emission Factors for Sewage Sludge Incinerator Sources.4-64 4-17 Arsenic Emission Factors for Medical Waste Incineration Sources .4-75 4-18 Arsenic Emission Factor for Crematories .4-79 4-19 1991 U.S. Crematory Locations by State.4-80 4- 20 Arsenic Emission Factors for Internal Combustion Engines.4-81 5- 1 Domestic Primary Lead Smelters And Refineries.5-2 5-2 Arsenic Emission Factor for Primary Lead Smelting Facilities.5-6 5-3 Arsenic Emission Factors for Secondary Lead Smelting Facilities.5-20 5-4 U.S. Secondary Lead Smelters Grouped According to Annual Lead Production Capacity. 5-22 5-5 Arsenic Emission Factors for Primary Copper Smelting Facilities.5-27 5-6 Primary Copper Smelters in the United States.5-30 5-7 Arsenic Emission Factors for Secondary Aluminum Production . 5-37 5-8 Ferroalloy Processes and Respective Product Groups. 5-40 5-9 Arsenic Emission Factors for Electric Arc Furnaces.5-46 5- 10 Arsenic Emission Factors for Iron and Steel Foundries.5-53 6- 1 Arsenic Emission Factors for Kraft Process Recovery Furnaces and Smelt Dissolving Tanks.6-8 6-2 Distribution of Kraft Pulp Mills in the United States (1997). 6-9 6-3 Arsenic Emission Factors for Lime Kilns .6-12 6-4 Arsenic Emission Factors for Sulfite Process Recovery Furnaces . 6-15 • IX LIST OF TABLES, continued Table Page 6- 5 Distribution of Sulfite Pulp Mills in the United States (1997) . 6-15 7- 1 Other Sources of Arsenic Emissions.7-2 7-2 Arsenic Emission Factor for Glass Manufacturing.7-4 7-3 Arsenic Emission Factor for Landfill Process Gas .7-7 7-4 Arsenic Emission Factors from Asphalt Concrete Production .7-15 7-5 Arsenic Emission Factor for Abrasive Grain Processing.7-20 7-6 1995 U.S. Primary Abrasive Grain Manufacturer Locations by State.7-21 7-7 Arsenic Emission Factors for Dry Process Portland Cement Kilns by Fuel and Waste Type ..7-26 7-8 Arsenic Emission Factors for Portland Cement Manufacturing Facilities.7-27 7-9 Portland Cement Production Facilities (1995). 7-28 7-10 Arsenic Emission Factors for Open Burning of Scrap Tires.7-34 7-11 Arsenic Emission Factors for Grain Milling .7-36 7-12 Arsenic Emission Factors for Process Heaters .7-37 A- 1 Summary of Emission Factors by Source Classification Codes . A-1 . x • . . ■ - • ■ •2 ' ' - ■ . LIST OF FIGURES Fi gure Page 4-1 Simplified Boiler Schematic .4-4 4-2 Single Wall-Fired Boiler.4-6 4-3 Simplified Atmospheric Fluidized Bed Combustor Process Flow Diagram.4-8 4-4 Spreader Type Stoker-Fired Boiler .4-9 4-5 Typical Process Component Options in a Hazardous Waste Incineration Facility ... 4-37 4-6 Typical Liquid Injection Combustion Chamber .4-38 4-7 Typical Rotary Kiln/Afterburner Combustion Chamber.4-40 4-8 Typical Fixed-Hearth Combustion Chamber.4-41 .4-9 Typical Mass Bum Waterwall Combustor.4-46 4-10 Simplified Process Flow Diagram, Gas Cycle for a Mass Bum/Rotary Waterwall Combustor.4-47 4-11 Mass Bum Refractory-Wall Combustor with Grate/Rotary Kiln .4-48 4-12 Typical RDF-Fired Spreader Stoker Boiler.4-50 4-13 Typical Modular Starved-Air Combustor with Transfer Rams.4-51 4-14 Typical Multiple-Hearth Furnace....4-59 4-15 Fluidized-Bed Combustor .4-61 4-16 Controlled-Air Incinerator.4-68 4-17 Excess-Air Incinerator.4-70 4- 18 Rotary Kiln Incinerator .4-72 5- 1 Typical Primary Lead-Processing Scheme.5-3 5-2 Simplified Process Flow Diagram for Secondary Lead Smelting.5-8 5-3 Cross-Sectional View of a Typical Stationary Reverberatory Furnace.5-10 xi LIST OF FIGURES, continued Figure F a S? 5-4 Cross-Section of a Typical Blast Furnace .i:.5-13 5-5 Side View of a Typical Rotary Reverberatory Furnace.5-15 5-6 Cross-Sectional View of an Electric Furnace for Processing Slag . 5-18 5-7 Typical Primary Copper Smelter Flow Sheet ...5-24 5-8 Copper Converter.5-26 5-9 Fugitive Emission Sources at Primary Copper Smelters.5-29 5-10 Typical Process Diagram for Pretreatment in the Secondary Aluminum Processing Industry .5-32 5-11 Typical Process Flow Diagram for the Secondary Aluminum Processing Industry. . . 5-33 5-12 Typical Ferroalloy Production Process .5-41 5-13 Typical Submerged Arc Furnace Design.5-43 5-14 Process Flow Diagram for a Typical Sand-Cast Iron and Steel Foundry.5-49 5- 15 Emission Points in a Typical Iron and Steel Foundry .5-50 6 - 1 Typical Kraft Pulping and Recovery Process .6-2 6-2 Direct Contact Evaporator Recovery Boiler . 6-4 6-3 Nondirect Contact Evaporator Recovery Boiler .6-5 6-4 Process Flow Diagram for Lime Kiln .6-10 6- 5 Process Diagram for Magnesium-Based Sulfite Pulping and Chemical Recovery ... 6-13 7- 1 General Process Flow Diagram for Batch-Mix Asphalt Paving Plants.7-9 7-2 General Process Flow Diagram for Drum-Mix Asphalt Paving Plants.7-12 7-3 General Process Flow Diagram for Counterflow Drum-Mix Asphalt Paving Plants .7-13 Xll LIST OF FIGURES, continued Figure Page 7-4 Flow Diagram for Abrasive Grain Processes. 7-18 7- 5 Process Flow Diagram Of Portland Cement Manufacturing Process.7-22 8- 1 Components of a High-Volume Ambient Air Sampler for Arsenic .8-3 8-2 EPA Method 29, BIF Method, and CARB Draft Method 436 Sampling Train.8-8 8-3 EPA Method 108 and CARB Method 423 Sampling Train .8-10 Xlll EXECUTIVE SUMMARY The 1990 Clean Air Act Amendments contain a list of 188 hazardous air pollutants (HAPs) which the U.S. Environmental Protection Agency must study, identify sources of, and determine if regulations are warranted. Of these HAPs, arsenic and arsenic compounds are the subject of this document. This document describes the properties of arsenic and arsenic compounds as air pollutants, defines production and use patterns, identifies source categories of air emissions, and provides emission factors. The document is a part of an ongoing EPA series designed to assist the general public at large, but primarily State/local air agencies, in identifying sources of HAPs and developing emissions estimates. Arsenic is emitted as an air pollutant from external combustion boilers, municipal and hazardous waste incineration, primary copper and zinc smelting, glass manufacturing, copper ore mining, and primary and secondary lead smelting. Emissions of arsenic from these activities are due to the presence of trace amounts of arsenic in fuels and materials being processed. In such cases, the emissions may be quite variable because the trace presence of arsenic is not constant. For instance, the concentration of arsenic in coal can vary by four orders of magnitude. Arsenic emissions also occur from agricultural chemical production and application, and also from metal processing due to the use of arsenic in these activities. In addition to the arsenic source information, information is provided that specifies how individual sources of arsenic may be tested to quantify air emissions. . xiv . • > . • ... ■ ; ' SECTION 1.0 PURPOSE OF DOCUMENT The Environmental Protection Agency (EPA) and State and local air pollution control agencies are becoming increasingly aware of the presence of substances in the ambient air that may be toxic at certain concentrations. This awareness has led to attempts to identify source/receptor relationships for these substances and to develop control programs to regulate toxic emissions. To assist groups interested in inventorying air emissions of various potentially toxic substances, EPA is preparing a series of documents that compiles available information on sources and emissions. Existing documents in the series are listed below. Substance Acrylonitrile Benzene Butadiene Cadmium Carbon Tetrachloride Chlorobenzene (update) Chloroform Chromium (supplement) Chromium Coal and Oil Combustion Sources Cyanide Compounds Dioxins and Furans Epichlorohydrin Ethylene Dichloride Ethylene Oxide EPA Publication Number EPA-450/4-84-007a EPA-450/R-98-011 EPA-454/R-96-008 EPA-454/R-93-040 EPA-450/4-84-007b EPA-454/R-93-044 EPA-450/4-84-007C EPA-450/2-89-002 EPA-450/4-84-007g EPA-450/2-89-001 EPA-454/R-93-041 EPA-454/R-97-003 EPA-450/4-84-007j EPA-450/4-84-007d EPA-450/4-84-0071 1-1 Substance EPA Publication Number Formaldehyde EPA-450/4-91-012 Lead EPA-454/R-98-006 Manganese EPA-450/4-84-007h Medical Waste Incinerators EPA-454/R-93-053 Mercury and Mercury Compounds EPA-453/R-93-023 Methyl Chloroform EPA-454/R-93-045 Methyl Ethyl Ketone EPA-454/R-93-046 Methylene Chloride EPA-454/R-93-006 Municipal Waste Combustors EPA-450/2-89-006 Nickel EPA-450/4-84-007f Perchloroethylene and T richloroethy lene EPA-450/2-89-013 Phosgene EP A-450/4-84-007i Polychlorinated Biphenyls (PCBs) EPA-450/4-84-007n Polycyclic Organic Matter (POM) EPA-450/4-84-007p Sewage Sludge Incinerators EPA-450/2-90-009 Styrene EPA-454/R-93-011 Toluene EPA-454/R-93-047 Vinylidene Chloride EPA-450/4-84-007k Xylenes EPA-454/R-93-048 This document deals specifically with arsenic and arsenic compounds. Its intended audience includes Federal, State and local air pollution personnel and others who are interested in locating potential sources of arsenic and arsenic compounds and in making gross emission estimates of these air pollutants. With the 1990 Amendments to the Clean Air Act (CAA), arsenic and arsenic compounds were both recognized for their toxic characteristics and added to the list of hazardous air pollutants (HAPs) presented in Section 112(d) to be evaluated in the development of maximum achievable control technology (MACT) standards. In addition, many States also recognize arsenic and arsenic compounds as toxic pollutants, and some States may impose their own regulations, which can be more stringent than the federal ones. 1-2 Arsenic air emissions have also been affected by regulatory activity from other agencies-including the Occupational Safety and Health Administration (OSHA), where regulations for reducing arsenic exposure to a variety of worker categories are in effect. A concerted effort was made during the development of this document to coordinate with the current work that is underway at the Office of Air Quality Planning and Standards (OAQPS) in developing MACT standards. Data were also available from National Emission Standard for Hazardous Air Pollutants (NESHAP) project files for the regulations pertaining to arsenic emissions from glass manufacturing plants, primary copper smelters, and arsenic trioxide and metallic arsenic production facilities. Also, as a result of the California “Hot Spots” program and other State source testing efforts (where such information is available through EPA's Source Test Information Retrieval System [STIRS] database and its Factor Information Retrieval [FIRE] System), data have been documented from source tests performed to demonstrate, among other reasons, permit applicability Such programs have been valuable for acquiring source-specific emissions data. However, despite the data generated by these programs, the available data on some potential sources of arsenic emissions are limited and the configurations of many sources will not be the same as those described in this document. Therefore, this document is best used as a primer to inform air pollution personnel about: (1) the types of sources that may emit arsenic, (2) process variations that may be expected within these sources, and (3) available emissions information that indicates the potential for arsenic to be released into the air from each operation. The reader is strongly cautioned against using the emission factors or emissions information contained in this document to try to develop an exact assessment of emissions from any particular facility. Available data are insufficient to develop statistical estimates of the accuracy of these emission factors, so no estimate can be made of the error that could result when these factors are used to calculate emissions from any given facility. It is possible, in some cases, that order-of-magnitude differences could result between actual and calculated emissions, depending on differences in source configurations, control equipment, and operating practices. 1-3 Thus, in situations where an accurate assessment of arsenic emissions is necessary, source- specific information should be obtained to confirm the existence of particular emitting operations, the types and effectiveness of control measures, and the impact of operating practices. A source test should be considered as the best means to determine air emissions directly from a facility or operation. As standard procedure, L&E documents are sent to government, industry, and environmental groups wherever EPA is aware of expertise. These groups are given the opportunity to review a document, comment, and provide additional data where applicable. Although this document has undergone extensive review, there may still be shortcomings. Comments subsequent to publication are welcome and will be addressed based on available time and resources. In addition, any comments on the contents or usefulness of this document are welcome, as is any information on process descriptions, operating practices, control measures, and emissions information that would enable EPA to update and improve the document's contents. All comments should be sent to: Group Leader Emission Factor and Inventory Group (MD-14) U. S. Environmental Protection Agency Research Triangle Park, North Carolina 27711 .1-4 SECTION 2.0 OVERVIEW OF DOCUMENT CONTENTS This section briefly outlines the nature, extent, and format of the material presented in the remaining sections of this report. Section 3.0 provides a brief summary of the physical and chemical characteristics of arsenic and arsenic compounds and an overview of their production, uses, and emission sources. This background section is useful in developing a general perspective on arsenic, how it is produced and consumed, and identifies potential sources of arsenic emissions. Section 4.0 describes various combustion source categories where arsenic emissions have been reported. For each type of combustion source, a description(s) of the combustor is given and potential arsenic emission points are identified on diagrams. Emission factors for potential arsenic emissions, before and after controls, are given where available. Section 5.0 focuses on air emissions of arsenic from the metallurgical industry. For each major production source category described in Section 5.0, a list of individual companies identified in that particular industry is provided. An example process description and a flow diagram with potential arsenic emission points are provided. Emission factors for potential arsenic emissions, before and after controls employed by industry, are given where available. Section 6.0 describes arsenic emissions from the pulp and paper industry. Process descriptions, emissions, and associated control techniques from kraft recovery furnaces, smelt dissolving tanks, lime kilns, and sulfite recovery furnaces are described. . 2-1 Section 7.0 summarizes other source categories that use arsenic and arsenic compounds in their processes and emit arsenic or source categories whose raw materials contain arsenic that 9 is emitted in the manufacturing process. The source categories discussed here include the production of glass, agricultural chemicals, wood preservers, lead pencils and art goods, prepared feeds, and Portland cement. Limited information on many of these sources is available; therefore, varying levels of detail on the processes, emissions, and controls are presented. Locations of facilities in each source category are provided, where available. Section 8.0 summarizes available procedures for source sampling and analysis of arsenic. This section provides an overview of applicable sampling procedures and cites references for those interested in conducting source tests. Appendix A presents a summary table of the emission factors contained in this document. This table also presents the factor quality rating and the Source Classification Code (SCC) or Area/Mobile Source (AMS) code associated with each emission factor. Each emission factor listed in Sections 4.0 through 7.0 was assigned an emission factor rating (A. B, C. D. E, or U) based on the criteria for assigning data quality ratings and emission factor ratings as required in the document Procedures for preparing Emission Factor Documents. 1 The criteria for assigning the data quality ratings to source tests are as follows: A - Tests are performed by using an EPA reference test method, or when not applicable, a sound methodology. Tests are reported in enough detail for adequate validation, and, raw data are provided that can be used to duplicate the emission results presented in the report. B - Tests are performed by a generally sound methodology, but lacking enough detail for adequate validation. Data are insufficient to completely duplicate the emission result presented in the report. C - Tests are based on an unproven or new methodology, or are lacking a significant amount of background information. D - Tests are based on generally unacceptable method, but the method may provide an order-of-magnitude value for the source. 2-2 Once the data quality ratings for the source tests had been assigned, these ratings along with the number of source tests available for a given emission point were evaluated. Because of the almost impossible task of assigning a meaningful confidence limit to industry-specific variables (e.g„ sample size vs. sample population, industry and facility variability, method of measurement), the use of a statistical confidence interval for establishing a representative emission factor for each source category was not practical. Therefore, some subjective quality rating was necessary. The following quality ratings were used in the emission factor tables in this document: A - Excellent. Emission factor is developed primarily from A- and B-rated source test data taken from many randomly chosen facilities in the industry population. The source category population is sufficiently specific to minimize variability. B - Above average. Emission factor is developed primarily from A- or B-rated test data from a moderate number of facilities. Although no specific bias is evident, it is not clear if the facilities tested represent a random sample of the industry. As with the A rating, the source category population is sufficiently specific to minimize variability. C - Average. Emission factor is developed primarily from A-, B-, and C-rated test data from a reasonable number of facilities. Although no specific bias is evident, it is not clear if the facilities tested represent a random sample of the industry. As with the A rating, the source category population is sufficiently specific to minimize variability. D - Below average. Emission factor is developed primarily form A-, B-, and C-rated test data from a small number of facilities, and there may be reason to suspect that these facilities do not represent a random sample of the industry. There also may be evidence of variability within the source population. E - Poor. Factor is developed from C- rated and D-rated test data from a very few number of facilities, and there may be reasons to suspect that the facilities tested do not represent a random sample of the industry. There also may be evidence of variability within the source category population. U - Unrated (Only used in the L&E documents). Emission factor is developed from source tests which have not been thoroughly evaluated, research papers, modeling data, or other sources that may lack supporting documentation. The data are not necessarily “poor,” but there is not enough information to rate the factors according to the rating protocol. 2-3 / This document does not contain any discussion of health or other environmental effects of arsenic, nor does it include any discussion of ambient air levels. 2-4 Tty References For Section 2.0 Procedures for Preparing Emission Factor Documents. EPA-454/R-95-015. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, October 1997. Factor Information Retrieval (FIRE) System, Version 4.0. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, June 1995. o 2-5 . ‘ * . ■ _ tV SECTION 3.0 BACKGROUND 3.1 Physical And Chemical Nature Of Arsenic And Arsenic Compounds Elemental arsenic (As, Chemical Abstract Service [CAS] No. 7440-38-2) is a silver-gray crystalline metallic solid that exhibits low thermal conductivity. Although arsenic is often referred to as a metal, it is classified chemically as a nonmetal or metalloid belonging to Group 15 (VA) of the periodic table. The principal valances of arsenic are +3, +5 and -3. Only one stable isotope of arsenic having mass 75 (100 percent natural abundance) has been observed. Arsenic typically exists in the (alpha)-crystalline metallic form which is steel-gray in appearance and brittle in nature, and in the beta-form, a dark gray amorphous solid. 1 “Metallic” arsenic remains stable in dry air, but its surface will oxidize when exposed to humid air, creating a superficial golden bronze tarnish that turns black upon prolonged exposure. The physical properties of arsenic are presented in Table 3-1. 1 Arsenic is found widely in nature, most often combined with oxygen, chlorine and sulfur. It is found in trace quantities in all living things, the atmosphere, water and geological formations." It is usually found in ores containing gold, silver, cobalt, nickel, and antimony. There are over 150 known arsenic-bearing minerals. Table 3-2 lists some of the more common minerals. 1 The most significant source of commercial arsenic is a byproduct from the treatment of copper, lead, cobalt and gold ores. The amount of arsenic found in lead and copper ores may range from a trace to 2 to 3 percent. 1 Commercial end uses of arsenic include the following: wood preservatives (e.g., chromium copper arsenate); electronics (e.g., semiconductors); medicinals and botanicals; agriculture products (e.g., fungicides, herbicides, pesticides, and silvicides); desiccants; nonferrous alloys; animal feed additives; glass; ceramics; and dyeing and 3-1 TABLE 3-1. PHYSICAL PROPERTIES OF ARSENIC Property Value Atomic weight 74.92 Melting point (at 39.1 MPa) a 816°C Boiling point. 615°C b Specific gravity (26°C) 5,778 kg/m 3 Specific heat 24.6 J/(mol-K) c Latent heat of fusion 27,740 J/(mol-K) c Latent heat of sublimation 31,974 J/(mol-K) c Linear coefficient of thermal expansion (20°C) 5.6 pm/(m-°C) Electrical resistivity (0°C) 26 fiQ/cm Crystal system hexagonal (rhombohedral) Lattice constants (26°C, mm) a = 0.376 e = 1.0548 Source: Reference 1. a To convert MPa to psi multiply by 145. b Sublimes. c To convert to cal/(mol-K) divide by 4.184. printing. Inorganic arsenic occurs naturally in many kinds of rocks. It is most commonly found with sulfide ores as arsenopyrite 4 Arsenic combined with carbon and hydrogen is classified as organic arsenic. Inorganic and organic arsenic compounds are typically white to colorless powders that do not evaporate, and have no smell or special taste. Metallic arsenic, which is not naturally-occurring, can be extracted from the flue-dust of copper and lead smelters in the form of arsenic trioxide or white arsenic, which can then be reduced with charcoal to produce metallic arsenic. The elemental, metallic form of arsenic is used as an alloying additive for metals (especially lead and copper shot), battery grids, cable sheaths, and boiler tubes. The high-purity or semiconductor grade of metallic arsenic is used in the manufacture of electronic products. The various classes of inorganic and organic arsenic compounds are discussed below. Table 3-3 3-2 TABLE 3-2. IMPORTANT ARSENIC-BEARING MINERALS Mineral CAS No. Arsenic Content, % Arsenopyrite (FeAsS) 1303-18-0 46 Lollingite (FeAs 2 ) 12255-65-1 73 Orpiment 12255-89-9 61 Realger 12044-30-3 70 Native Arsenic 7440-38-2 90-100 Source: Reference 1. presents a summary of the chemical formulas and end uses of the most commonly used arsenic compounds. 5 3.1.1 Inorganic Compounds Arsenic Hydrides The primary binary compound of arsenic and hydrogen is arsine (“arsenic hydride”). It is the only known hydrogen compound of arsenic. Arsine is a colorless, very poisonous gas that exhibits an unpleasant garlic like odor. It is formed when any inorganic arsenic-bearing material is brought in contact with zinc and sulfuric acid. It can be accidentally formed by the reaction of arsenic impurities in commercial acids stored in metal tanks. Arsine is not particularly stable and begins to decompose into its elements below 572°F. In the presence of moisture, light can affect the decomposition. Arsine is capable of reducing many substances. For example, it precipitates metallic silver from silver nitrate solution. The pure gas is stable at normal temperature. While it is not oxidized by air at room temperature, it can be ignited with the formation of arsenic, arsenic trioxide, or arsenic pentoxide, depending upon the supply of air. Arsine is used as a dopant in the semiconductor industry, 3 and is used to produce gallium arsenide, GaAs, which is used in the field of optoelectronic and microwave devices. 3-3 TABLE 3-3. COMMON ARSENIC COMPOUNDS Compound Chemical Formula or Description Uses Arsenic acid H 3 AsO 4 -0.5H 2 O Manufacture of arsenates, glass making, wood treating process, defoliant (regulated), desiccant for cotton, soil sterilant. Arsenic disulfide As 2 S2 Leather industry, depilatory agent, paint pigment, shot manufacture, pyrotechnics, rodenticide, taxidermy. Arsenic pentafluoride AsF 5 Doping agent in electroconductive polymers. Arsenic pentasulfide As 2 S 5 Paint pigments, light filters, other arsenic compounds. Arsenic pentoxide As 2 0 5 Arsenates, insecticides, dyeing and printing, weed killer, colored glass, metal adhesives. Arsenic thioarsenate As(AsS 4 ) Scavenger for certain oxidation catalysts and thermal protectant for metal-bonded adhesives and coating resins. Arsenic tribromide AsBr 3 Analytical chemistry, medicine. Arsenic trichloride AsCl 3 Intermediate for organic arsenicals (pharmaceuticals, insecticides), ceramics. Arsenic trifluoride AsF 3 Fluorinating reagent, catalyst, ion implantation source, and dopant. Arsenic trioxide As-,0 3 Pigments, ceramic enamels, aniline colors, decolorizing agent in glass, insecticide, rodenticide, herbicide, sheep and cattle dip, hide preservative, preparation of other arsenic compounds. Arsenic tnsulfide As 2 S 3 Pigment, reducing agent, pyrotechnics, glass used for infrared lenses, semiconductors, hair removal from hides. Arsenic hydride (arsine) AsH 3 Organic synthesis, military poison, doping agent for solid-state electronic compounds. Source: Reference 5. 3-4 Other Arsenic Hydrides In general, arsenides have little commercial uses. While some arsenides have a defined composition, others are mixtures. Many arsenides occur in nature, and some of the naturally occurring arsenides include Cu 3 As (domeykite), FeAs 2 (lollingite), NiAs 2 (chloanthite), NiAs (niccolite), and CoAs 2 (smaltite). Diarsine, As 2 H, is a byproduct that occurs from the preparation of arsine by treatment of a magnesium aluminum arsenide alloy with dilute sulfuric acid. It can also occur by passing arsine at low pressure through an ozonizer-type discharge tube. As a gas, diarsine is fairly stable, but rather unstable in condensed phases. Arsenic Halides While arsenic forms a complete series of trihalides, only arsenic pentafluoride is a well-known pentahalide. Table 3-4 lists some known arsenic halides. 1 All of the arsenic halides are covalent compounds that hydrolyze in water 1 and can be formed by direct combination of the elements. Arsenic trichloride is the most common and commercially significant of all arsenic halides. W T ith a low boiling point, it is easily separated from tin trichloride and the chlorides of other metals. It can also be formed by spontaneous combustion of the elements. Arsenic trichloride has been used as a starting material for the production of numerous organoarsenic compounds and for the preparation of chlorine derivatives of the arsines. In addition, it is used as a dopant in the semiconductor industry and in the production of high-purity arsenic metal. Other arsenic halides include arsenic trifluoride, arsenic pentafluoride, arsenic pentachloride, arsenic tribromide, arsenic tniodide, and arsenic diiodide. Arsenic Oxides and Acids The only arsenic oxides that are commercially significant are the trioxide and pentoxide. Arsenic trioxide and arsenic pentoxide are described in detail below. 3-5 TABLE 3-4. PHYSICAL PROPERTIES OF ARSENIC HALIDES CO >1 > «« o m 0 «r> 00 VO 10 VO co O VO ON o VO m CN VO cn c CN CN CN cn 02 02 a. CO U O oo 00 CN 8 CN O CN a. VO CN CO CN c« CQ 02 U 0 O OO CN CN c£ od d r- vd co d 1 1 02 c 3 « .< C/2 » w 02 U c 7 -o T 3 o r~" in zz C /3 Z3 rv cn .o' C 3 0x2 00 C /5 .ST tj "U <—* 3 C /3 C /3 C/3 C /3 0 c/5 IE v 02 02 02 £ /-N U. c U* O E O _o C/3 o u o O 0 *02 T 3 o 02 02 u- CN m _ O n- o z or, od Tj- cn *n co m cn cn TT CO Tf d rf Tf Tf < oc 00 00 00 OO U r~ r- r- r- r- r- r- r- r- w-> 02 u- C A rO m Urn tL. < u CQ — C/3 s —^ c/3 C/3 rr CT 3 < 02 < < C/3 02 02 rE ' lZ 02 02 < E T 3 0 3 T 3 TD 02 C/3 U- 0 c u. 0 E IS Us 3 0 ~o < c C 02 -C 02 Lm X 0 u- Li L U u. _02 _02 02 02 02 c c c c c 02 02 02 02 02 c^ C/3 c/5 C/3 C/3 u- U* u. u« < < < < < V u c W c ID > 5} c OJ 0/ U 3 CO 0> O U a « 8. E H 3-6 Arsenic Trioxide —Arsenic trioxide is also known as white arsenic. It is the most commercially important arsenic compound. It can occur in two different crystalline forms and one amorphous variety. The octahedral or cubic modification, arseiiolite, is the most common form and is stable at room temperature. It changes into a monoclonic modification, claudetite (consisting of sheets of AS0 3 pyramids sharing oxygen), at temperatures above 430°F. This modification is formed when condensation occurs at temperatures above 430°F. Condensation above 482 °F will generally form the amorphous, glassy phase which devitrifies into the octahedral modification at room temperature. This octahedral variety is a white solid that sublimes above 275°F and melts at 527°F under its own vapor pressure. 1 Arsenic trioxide slightly dissolves in water to form a weakly acidic solution. It is soluble in acids and bases (amphoteric). It can be made by burning arsenic in air, or by the hydrolysis of an arsenic trihalide. Commercially, it is prepared by roasting arsenopyrite. It is often used as a primary analytical standard in oxidimetry since it is readily attainable in a high state of purity and is quantitatively oxidized by many reagents commonly used in volumetric analysis (e.g.. dichromate, nitric acid, hypochlorite, and iron(DI)). Arsenic Pentoxide — Arsenic pentoxide is a “white glassy mass,” made up of equal numbers of octahedra and tetrahedra sharing comer oxygens to give cross-linked strands. 3 It is an oxidizing agent capable of liberating chlorine from hydrogen chloride. The compound deliquesces in air to form arsenic acid. It dissolves in water slowly, is thermally unstable, and begins to decompose near the melting point, around 572°F. The vapor is made up of arsenic trioxide and oxygen. The pentoxide can be made by reacting arsenic trioxide with oxygen under pressure, or by dehydration of crystalline arsenic acid at temperatures above 392°F (the best method). 1 Arsenous Acid —Arsenous acid is a weak acid with a dissociation constant of 8xl0* 16 at 77°F. It is known to exist only in solution. Arsenic Acid —Arsenic acid, is known in the solid state as the hemihydrate H 3 AsO 4 -0.5H o O and occurs as rhombic, deliquescent crystals. It is made by the oxidation of .3-7 arsenic trioxide with concentrated nitric acid. Arsenic acid will lose water upon heating to 248 °F and forms pyroarsenic acid. At elevated temperatures, more water is lost and meta-arsenic acid forms. In an acidic solution, arsenic acid and its salts are strong oxidizing agents. Arsenic acid is used as a defoliant and as a starting material for important inorganic and organic arsenic compounds. 3 Various salts (arsenates) are derived from arsenic acid, and are described in detail below. Arsenates Arsenates are oxidizing agents and are reduced with concentrated hydrochloric acid or sulfur dioxide. They are generally similar to the phosphates in their compositions and solubilities. Of the many salts of arsenic acid, the salts of potassium, sodium, calcium and lead are important commercially. Arsenates of calcium or lead are often used as insecticides. When a solution of ortho-arsenate is treated with silver nitrate in neutral solution, a chocolate-brown precipitate of silver ortho-arsenate forms. Silver ortho-arsenate can be used as a test to distinguish arsenates from phosphates. With hydrofluoric acid, ortho-arsenate solutions yield hexafluoroarsenates (e.g., potassium hexafluoroarsenate). Arsenic Sulfides Table 3-5 presents the physical properties of the common arsenic sulfides. 1,3 These arsenic sulfides are described in detail below. Arsenic Disulfide -Arsenic disulfide (“red glass”) exists in ruby-red crystals or as an amorphous reddish mass. It occurs naturally as the mineral realger. At 513 °F it changes into a black allotropic modification and at 585°F the compound melts. Its purity and fineness rather than its chemical composition determine its commercial value. Industrially manufactured red arsenic glass varies in its composition. Today, red glasses typically contain around 61 to 64 percent arsenic and 39 to 36 percent sulfur. Commercially, the compound is produced by heating a mixture of iron pyrites and arsenopyrites or by heating arsenic trioxide with sulfur. It can also be made by prolonged treatment of arsenous sulfide with boiling aqueous sodium 3-8 TABLE 3-5. PHYSICAL PROPERTIES OF COMMON ARSENIC SULFIDES Arsenic Sulfides CAS No. Molecular Formula Color and Physical State at 25 °C Arsenous sulfide (orpiment) 12255-89-9 As 2 S 3 - . Yellow solid Arsenic sulfide (realgar) 12279-90-2 As 4 S 4 Gold or orange solid Arsenic pentasulfide 1303-34-0 As 4 S 10 Yellow solid Tetraarsenic trisulfide 1303-41-9 AS 4 S 3 Orange-yellow Tetraarsenic pentasulfide 25114-28-7 As 4 S^ Source: Reference 1. bicarbonate, or by heating a sodium bicarbonate-arsenous sulfide mixture in a sealed tube. Water does not affect it, however it will oxidize in nitric acid and inflame in chlorine. Red glass is primarily used as a depilatory in the manufacture of fine leather, and also used in pyrotechnics. Arsenic (TIT) Sulfide -Arsenic (III) sulfide is known as orpiment and occurs as a yellow mineral. It is made by precipitation of trivalent arsenic compounds with hydrogen sulfide. The colloidal solution of the arsenic trisulfide can be flocculated with hydrochloric acid, in which it is insoluble. It readily dissolves in basic reagents. Orpiment contains unchanged arsenic trioxide and is poisonous. It was used in the past for cosmetic purposes, but currently it is used in the semiconductor industry, in the production of infrared-permeable windows, and as a pigment. Arsenic (V) Sulfide -Arsenic (V) sulfide (also referred to as arsenic pentasulfide) is made by fusing stoichiometric quantities of arsenic and sulfur powder or by precipitation from highly acidic arsenate (V) solution with H 2 S. Arsenic (V) sulfide will decompose into arsenic (III) sulfide and sulfur. The compound is stable in air up to temperatures of 203 °F, but begins to dissociate into arsenous sulfide and sulfur at higher temperatures. It can be hydrolyzed by boiling with water resulting in arsenous acid and sulfur. 3-9 3.1.2 Organic Arsenic Compounds Arsenic combines easily with carbon to form a wide variety of organic compounds with one or more As-C bonds. There are many known organoarsenic compounds. Table 3-6 presents a number of examples . 1 Arsenic compounds used in agriculture as plant protection agents and pesticides have largely been replaced by metal-free compounds. In the United States, only certain preparations are allowed for use in some States (e.g., those of the Ansar series). For wood preservatives, arsenic compounds are used solely in compound preparations. Organic arsenic compounds can be grouped into aliphatic organoarsenic compounds and aromatic organoarsenic compounds. Both of these groups are described in detail below. Aliphatic Organoarsenic Compounds This class of compounds is still used as herbicides and fungicides in rice, cotton, fruit, and coffee plantations, particularly in Eastern Asia. The three main aliphatic organoarsenic compounds are described below. Methanearsonic Acid Salts of methanearsonic acid, particularly the iron ammonium salt, Neoasozin, are used as a fungicide in rice growing. The sodium, ammonium, and diethanolammonium salts are used as herbicides in cotton growing. 3 Dimethylarsinic acid Dimethylarsinic acid, also called Ansar 160, is used as a total herbicide and desiccant. Generally, it is produced by reaction of methyl halide with a salt of arsenous acid. 3 3-10 TABLE 3-6. ORGANIC ARSENIC COMPOUNDS Compound CAS Number Molecular Formula Ethylarsine ' ‘ 593-59-9 C 2 H 7 As Diethylarsine 692-42-2 C 5 H n As Triphenylarsine 603-32-7 C, 8 Hi 5 As Dimethylbromoarsine 676-71-1 C 2 H 6 AsBr Methyldifluoroarsine 420-24-6 CH 3 AsF Oxophenylarsine 637-03-6 C 6 H 5 AsO Phenylarsonous acid 25400-22-0 C 6 H 7 As0 2 Dimethylarsinous cyanide 683-45-4 C 3 H 6 AsN Methyl diphenylarsinite 24582-54-5 C 13 H 13 AsO Tetrakis(trifluoromethyl) diarsine 360-56-5 C 4 As 2 F 12 Pentamethylpentaarsolane 20550-47-4 C 5 H 15 As 5 4-Ethvlarsenin 76782-94-0 C 7 H 9 As 1 -Chloroarsolane 30077-24-8 C 4 H 8 AsO l//-arsole 4542-21-6 C 4 H 5 As Phenylarsonic acid 98-05-5 C 6 H 7 As0 3 Diphenylarsinic acid 4656-80-8 C^H] jAs0 2 Arsonoacetic acid 107-38-0 C 2 H 5 As0 5 Diethyl methylarsonate 14806-25-8 C^H^AsC^ Triphenylarsine oxide 1153-05-5 ^18^15^0 Tetrachlorophenylarsorane 29181-03-1 ^HjAsC^ Tetramethylarsonium perchlorate 84742-76-7 C 4 H 12 AsC10 4 Triphenvlarsonium 2-propenylide 88329-28-6 _C 2 iHi 9 As_ Source: Reference 1. 3-11 Aromatic Organoarsenic Compounds There are two classic methods of preparing aromatic organoarsenic compounds. In one method, aniline is reacted with arsenic acid at 392 °F as seen in the sulfonation of organic compounds: C 6 H 5 NH 2 + H 3 As0 4 -> H 2 N + C 6 H 4 + AsO(OH) 2 In the other method, diazo compounds are reacted with sodium arsenate (IH): C 2 H 5 N 2 C1 + Na 3 As0 3 ~> C 6 H 5 + AsO(ONa) 2 + N 2 + NaCl Of the two methods, the second method has proven to be the most commercially important in producing arsonic acids. In a more modem process, arsenic acid complexed with EDTA is added at 266°F to a solution of excess aniline in perchloroethylene. The water of reaction and any unreacted aniline are separated off, and the bis(4-aminophenyl)arsinic acid intermediate is converted by acidic hydrolysis into arsanilic acid. Arsonic acids are used in various industrial applications. For example, they have been used as corrosion inhibitors for iron and steel, and as additives for motor fuel, agricultural bactericides, herbicides, and fungicides. The primary use of the arsonic acids was in their supplementary processing to arsenobenzenes and “arsenic oxides” by reduction with S0 2 , phosphorus trichloride, sodium dithionite, phosphorous acid, or tin (II) chloride. Reduction with zinc dust and hydrochloric acid yields the arsines, which are reoxidized in air (e.g., phenylarsine, rapidly oxidized in air to form the arseno compound, C 6 H 5 As n ). Additional uptake of oxygen is considerably slower unless catalyzed (e.g., by iron). 3 3-12 Arsenic oxides are relatively stable. All arsenic oxide compounds are oxidized to arsonic derivatives by strong oxidants, including hydrogen peroxide, halogens, and Chloramine—T (sodium p-toluenechlorosulfonamide). V f The aromatic arsonic acids are dibasic. Aqueous solutions of the monosodium salts are neutral to mildly acidic, whereas those of the disodium salts are slightly alkaline (pH of 8 to 9). Magnesium and calcium salts are typically soluble in cold water, but upon heating, they precipitate to practically insoluble deposits. Because magnesium and calcium salts are soluble in cold water, they can be used to separate arsonic salts from cold solutions. Arsonic acids generally crystallize well, and their stability depends on the substituents on the benzene ring. Some form azo dyes that contain both arsonic acid and sulfonic acid groups, and are used in the analysis of metals. Aromatic Arsenobenzenes Aromatic arseno compounds have amino or hydroxyl groups and are soluble in acids and alkalis. Aromatic arseno compounds will become soluble in water with the addition of a formaldehyde sulfoxylate or formaldehyde hydrogen sulfite into the amino group. Organic Oxoarsenic Compounds (“Arsenic Oxides”) The reduction of organoarsenic compounds can be controlled by using an appropriate reducing agent so that reaction terminates at the preferred intermediate stage. However, this does not occur with oxidation. In the most commonly used method for the production of organic oxoarsenic compounds from arsonic acids, the acid is directly reduced to the anhydride of the arsonous acid with S0 2 . Organic oxoarsenic compounds are the anhydrides of the arsonous acids. They are extremely poisonous, amphoteric substances barely soluble in water. When dissolved in acids and alkalis, they form salts and can be precipitated from those solutions by carbon dioxide or • t 3 ammonium chloride. 3-13 3.2 Fate Of Arsenic As previously stated, arsenic is ubiquitous, and is emitted naturally from many sources (e.g., volcanoes, forest wild fires, erosion from mineral deposits). However, the releases originating from human activities (e.g., metal smelting, chemical production and use, coal combustion, waste disposal, pesticide application) are the emissions that can cause substantial environmental contamination. The greatest environmental concentrations of arsenic have been observed in air and soil around mining and smelter operations, whereas coal combustion distributes arsenic to the air in much lower concentrations over a wider area. A brief discussion of the fate of arsenic upon being released to the air, water, and soil is provided below. 3.2.1 Fate of Arsenic in Soil The majority of soils naturally contain low levels of arsenic (1 to 5 ppm) but certain industrial wastes and pesticide applications can increase concentrations. Approximately 80 percent of the total amount of arsenic that is released to the environment from anthropogenic activities is released to soil. 6 The major anthropogenic sources contributing to arsenic in soils include the application of pesticides and disposal of solid wastes from fossil fuel combustion and industrial processes. Organoarsenical pesticides (e.g., monosodium methanearsonate, disodium methanearsonate) applied to soils are metabolized by soil bacteria to form alkylarsines and arsenate. 7,8 Land application of sewage sludge has proven to be another source of arsenic in soil. While arsenic has been observed in soil at various hazardous waste sites, it is not always obvious that it was a result of the waste site or from natural causes. Regardless of the source or form of arsenical, arsenic will react with soil components. The predominant reaction is adsorption onto and reaction with hydrous iron and aluminum oxides which coat soil particles. Heavier soils with a higher clay content and hydrous oxide content adsorb more arsenic than do lighter sandier soils with low clay content. 8 In addition, arsenicals react with ions in solution, such as iron, aluminum, calcium, and magnesium, but may 3-14 • 2 V also include manganese and lead. Each ion detaches a part of the arsenical depending on the solubility of the compound and the quantity of reactants present. Hence, a soil may be saturated relative to some compounds and not others. The pH of the soil will affect the solubility of these compounds; therefore, changing the soil pH may affect each arsenical’s solubility. There are two known types of oxidation that are responsible for transforming arsenicals environmentally. One type destroys the carbon/arsenic bond and is associated with microbial activity, while the other type causes a change in oxidation state which may or may not be affected by microbial activity. Transformations of arsenic in soil are similar to those seen in aquatic systems, with As +5 predominant in aerobic soils; As +3 in slightly reduced soils (e.g., temporarily flooded); and arsine, methylated arsenic, and elemental arsenic in very reduced conditions (e.g., swamps and bogs). 6,8 Some arsenate may be reduced to arsenite under certain environmental conditions. Arsenic in sediments or in flooded anaerobic soil may be reduced as a function of reduction/oxidation potential. 3.2.2 Fate of Arsenic in Water Arsenic can be found in surface water, groundwater, and finished drinking water throughout the United States. The majority of arsenic in natural water is a mixture of arsenate and arsenite, with arsenate usually predominating. 8 Arsenic is released to water in several ways, including natural weathering processes, discharge from industrial facilities, and leaching from landfills, soil or urban runoff. Once in water, arsenic can go through a complex series of transformations, including oxidation-reduction reactions, ligand exchange, and biotransformations. The factors that most strongly influence the transformations that arsenic will undergo are the oxidation-reduction potential (Eh), pH, metal sulfide and sulfide ion concentrations, iron concentrations, temperature, salinity, and distribution and composition of the biota. 8 Arsenate is usually the predominant form of arsenic in water, however, aquatic microorganisms may reduce the arsenate to arsenite and a variety of methylated arsenicals. 3-15 Once in water, the transport and partitioning of arsenic will depend upon its chemical form as well as interactions with other materials present. Any soluble forms will move with the water, and can be carried long distances through rivers. However, arsenic can also be adsorbed from water onto sediments and soils, particularly clays, iron oxides, aluminum hydroxides, manganese compounds, and organic material. 8 Once in sediments, arsenic can be released back into the water through chemical and biological interconversions of arsenic species. 3.2.3 Fate of Arsenic in Air Arsenic can be released to air from natural sources (e.g., volcanoes and forest fires) and from various industrial sources (e.g., coal combustion, smelter and mining activities) and pesticide application. Arsenic in air primarily exists in the form of particulate matter (mostly in panicles less than 2 pm in diameter) and is usually a mixture of arsenite and arsenate. These panicles can be transported by wind and air currents until they are brought back to earth by wet or dry deposition. The residence time of arsenic bound to particulate depends on particle size and meteorological conditions; however, a typical value is approximately 9 days. 8 As might be expected, levels of arsenic in air vary with distance from the source, height of the stack, and wind speed. In general, large cities have higher levels of arsenic air concentrations than smaller ones. This is probably due to emissions from coal powered plants. In addition, areas that are near nonfenous metal smelters have reported extremely high arsenic air concentrations (up to 1.56x10' 10 lb/ft 3 ). 8 3.2.4 Fate of Arsenic in Plants and Food Once arsenic enters the environment, it enters the food chain. Bioconcentration of arsenic occurs in aquatic organisms, mainly in algae and lower invertebrates. Low levels of arsenic have been measured in freshwater invertebrates and fish, while higher levels have been observed in marine oysters. Apparently, biomagnification in aquatic food chains is not significant, although some fish and invertebrates have high levels of arsenic compounds. 3-16 Once arsenic is in the soil, it can be taken into plants via root uptake (plants can also obtain arsenic through foliar absorption). In general, the greater the amount of arsenic available for uptake, the greater the amount that will be absorbed by a plant. However, available arsenic is not proportional to total arsenic. A low (10 to 50 ppm) arsenic content in a sandy soil may be more phytotoxic (i.e., available) than much higher levels (200 to 500 ppm) in a heavier clay soil and, therefore, a plant grown on sandy soil will contain higher residue levels. 8 3.3 Overview Of Production And Use Commercial arsenic is primarily produced as a by-product in the smelting of nonferrous metal ores containing gold, silver, lead, nickel, and cobalt. In 1985, all United States domestic production of arsenic ceased. ■H At the present time, approximately 17 countries (the U.S. is not included) recover arsenic as arsenic trioxide from the smelting or roasting of nonferrous metal ores or concentrates. According to the U.S. Bureau of Mines, in 1993, the United States imported all of the arsenic it required (almost 13,228 tons). Table 3-7 presents U.S. import data for arsenicals from 1991 to 1993 by country. 9 About 97 percent was imported as arsenic trioxide, and approximately 3 percent as metallic arsenic. 9 China, the world’s largest producer of both arsenic trioxide and metallic arsenic, sold large amounts of both commodities to the United States. Historically, arsenic was used in agricultural applications as an insecticide, herbicide, and cotton desiccant. However, with an increase in environmental awareness and a better understanding of the toxicity of arsenic, most of the agricultural uses for arsenic were banned. Around 1975, the use of arsenic as a wood preservative began to grow and by 1990, 70 percent of arsenic consumed in the United States was used by the wood preservative industry and 20 percent by the agricultural industry. 10 The primary use of arsenic in the United States today is in the manufacture of chemicals, with arsenic trioxide being the sole starting material. 3 Metallic arsenic has a limited demand but still finds use in electronic and semiconductor applications. The production and uses of both metallic arsenic and arsenic trioxide are presented below. 3-17 TABLE 3-7. U.S. IMPORTS FOR CONSUMPTION OF ARSENICALS, BY COUNTRY Class Country 1993 Quantity (tons) Arsenic trioxide Australia — Belgium 747 Chile 6,670 China 12,908 Finland France 2,080 Germany 17 . Ghana — Hong Kong 1,813 Mexico 4,304 Philippines 1,267 South Africa, Republic of 132 Sweden — Taiwan — United Kingdom 19 Other 389 Total 30,346 Arsenic Metal Belgium — Canada a China 762 Germany 12 Hong Kong 19 Japan 52 Philippines — United Kingdom 1 Tota! b 845 Source: Reference 9. a Less than 1/2 unit. b Data may not add to totals shown because of independent rounding. 3-18 3.3.1 Metallic Arsenic Metallic arsenic is mainly used in nonferrous alloys. Small amounts (around 0.5 percent) of arsenic are added to lead-antimony grid alloys used in lead^acid batteries to increase endurance # * and corrosion resistance. Additions of the same order (0.02 to 0.5 percent) to copper alloys raise the recrystallization temperature and improve high temperature stability and corrosion resistance. Additions of arsenic (up to 2 percent) to lead in shot improve the sphericity of lead ammunition. While limited, there is a demand for high-purity arsenic (99.99 percent and greater) for use in the semiconductor and electronics industry. It is used in electronics together with gallium or indium for producing light emitting diodes (LED), infrared detectors, and lasers. High-purity metallic arsenic is used in the production of photoreceptor alloys for xerographic plain paper copiers. 1 In the past (1974 to 1986), arsenic was supplied domestically by ASARCO, Inc., which shut down its operation due to economic and environmental pressures. The United States must now rely upon imports from Japan, Canada, and the United Kingdom for its high purity metallic arsenic. Metallic arsenic may also be used in condensers, evaporators, ferrules, and heat exchanger and distillation tubes. 1 3.3.2 Arsenic Trioxide Arsenic trioxide is easily volatilized during the smelting of copper and lead concentrates, and is therefore concentrated with the flue dust. 1 Most of this raw material originates from copper smelters, although some also comes from lead, cobalt, and other smelters. Crude flue dust may contain up to 30 percent arsenic trioxide, the balance being oxides of copper or lead, and other metals such as antimony. This crude flue dust is subsequently upgraded by mixing with a small quantity of pyrite or galena and roasting. Pyrite and galena are added to prevent arsemtes from forming during roasting. 1 During roasting, the gases and vapors are allowed to pass through a cooling flue which consists of a series of brick chambers or rooms called kitchens. The arsenic vapor which condenses in these chambers is of varying purity (from 90 to 95 percent). 1 Higher purity products can be obtained by resubliming the crude trioxide, an operation typically carried out in a reverberatory furnace. 3-19 Since arsenic trioxide is a by-product, production is not based on the demand for arsenic but by the demand for copper, lead, etc. 3 The biggest consumers of arsenic trioxide are the United States, Malaysia and the United Kingdom. 3 Until the late 1980s, the United States was the main supplier of arsenic trioxide for domestic use. Now it must rely entirely on imports. Most arsenic is used in the form of compounds with arsenic trioxide as the sole starting material. Arsenic trioxide is the primary commodity of commerce from which a number of important chemicals are manufactured. Refined arsenic trioxide, once used as a decolorizer and fining agent in the manufacturing of bottleglass and other types of glassware, is being replaced by arsenic acid for environmental reasons. Arsenic acid is used in the preparation of wood preservative salts, primarily chrome copper arsenate. Arsenilic acid is used as a feed additive for poultry and swine. Sodium arsenite is useful for cattle and sheep dips. 3-20 1 . ■w - References For Section 3.0 Kirk-Othmer Encyclopedia of Chemical Technology. 4th Edition, Volume 3. New York, New York: John Wiley and Sons, Inc., 1992. pp. 624-659. 2 Lederer, W.H. and R.J. Fensterheim (eds). Arsenic: Industrial, Biomedical, Environmental Perspectives. New York, New York: Van Nostrand Reinhold, 1983. 3. Hanusch, K., H. Grossman, K.A. Herbst, B. Rose, and H.V. Wolf. Arsenic and Arsenic Compounds. In: Ullman's Encyclopedia of Industrial Chemistry. 5th ed. .Volume A3. W. Gerhartz, Y.S. Yamamoto, F.T. Campbell, R. Pfefferkom, J.F. Rounsaville, eds. Federal Republic of Germany: VCH, 1985. pp. 113-141. 4. U.S. EPA. Clean Air Act, Section 112(h) Candidate Pollutants , draft report. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Visibility and Ecosystem Protection Group, 1996. 5. Hawley's Condensed Chemical Dictionary, 12th ed. R.J. Lewis, Sr., ed. New York, New York: Van Nostrand Reinhold, 1993. 6. U.S. EPA. Arsenic. In: Intermedia Priority Pollutant Guidance Documents. Washington. D.C.: U.S. Environmental Protection Agency, Office of Pesticides and Toxic Substances, 1982. 7. Hood, R.D. Cacodylic Acid: Agricultural Uses, Biological Effects, and Environmental Fate. Report to Veterans Administration Central Office, Agent Orange Projects Office, Washington, D.C., by the University of Alabama, Tuscaloosa, Alabama, and R.D. Hood and Associates, Northport, Alabama, 1985. 8. U.S. Department of Health and Human Resources. Toxicological Profile for Arsenic, Draft Update. Public Health Service. Agency for Toxic Substances and Disease Registry, February 18, 1992. 9. U.S. Department of Interior. Mineral Industry Surveys - Arsenic in 1993. Washington, D.C.: U.S. Department of Interior, Bureau of Mines, June 22, 1994. 10. Loebenstein, J.R. The Materials Flow of Arsenic in the United States. Washington, D.C.: U.S. Department of Interior, Bureau of Mines, 1994. pp. 1-12. 3-21 ■ ■ ' wmm . . - I EE ■ . ■ - ■ . ■ ■ SECTION 4.0 EMISSIONS OF ARSENIC AND ARSENIC COMPOUNDS FROM COMBUSTION SOURCES This section contains process descriptions, available emission factor data, and source locations for source categories that emit arsenic and arsenic compounds during combustion. These source categories include fuel combustion in stationary external combustion, incineration of various types of waste, including municipal waste, sewage sludge, medical waste, hazardous waste, as well as internal combustion, kraft pulping lime kilns, and crematories. There are few emission controls that are dedicated solely to reducing arsenic emissions from combustion sources. However, the control strategies used to reduce particulate matter (PM) in general have been found to be effective in controlling arsenic emissions in particulate form. Where a specific emission control strategy has been identified to reduce arsenic emissions from a particular combustion source discussed in this section, that control strategy is discussed as part of the process description for that source. In many cases throughout this section, emission factor data are provided for both controlled and uncontrolled combustion units that are typically found in a particular source category. 4.1 Stationary External Combustion The combustion of solid, liquid, and gaseous fuels such as coal, wood, fuel oil, and natural gas has been shown to be a source of arsenic emissions. Arsenic emission rates depend on both fuel characteristics and combustion process characteristics. Emissions of arsenic originate from arsenic compounds contained in fuels and emitted during combustion. 1,2 Because metals such as arsenic only change forms (chemical and physical states) and are never destroyed during combustion, the amount of arsenic in the original fuel or waste will be the amount of AA arsenic found in the ash or emitted from stacks controlled by air pollution control devices (APCDs). 3 ' 4 Arsenic concentration in coal depends on the type of coal. Some specific arsenic concentrations in coal are as follows: anthracite coal contains approximately 8 ppm arsenic; bituminous coal contains 20 ppm arsenic; subbituminous coal contains 6 ppm arsenic; and lignite coal contains 23 ppm arsenic. 5 . Arsenic and arsenic compound emissions may be reduced from combustion sources by using PM control devices and lower combustion and APCD temperatures. These arsenic reduction techniques are discussed briefly below. In general, use of PM control devices in combustion/air pollution control systems can be viewed as a surrogate for controlling emissions of arsenic and other metals. 4 The most effective means of controlling arsenic emissions to the atmosphere are: (1) minimizing arsenic vaporization in the combustion zone and (2) maximizing small particle collection in the APCD. Arsenic compounds, like many heavy metal compounds, vaporize at elevated temperatures and, as temperatures drop, only a fraction of the vaporized metal condenses. The remaining vaporized metal can escape through the PM APCD uncontrolled. During the combustion process, many trace metals (including arsenic) volatilize and then, upon cooling, condense on all available particulate surface area. These submicrometer particles with very high surface areas can carry a very high concentration of condensed metal. This phenomenon is known as “fine particle enrichment.’’ There are three general factors favoring fine panicle enrichment of metals: 4 • Small panicle size; • Large number of particles; and • Low flue gas temperatures. 4-2 There is some evidence that fine particle enrichment of metals on PM is not as prevalent at higher flue gas temperatures. It is believed that as long as the flue gas temperatures remain high, the metals tend to remain volatized, such that they do not condense and bond with PM. 4 The primary stationary combustion sources emitting arsenic compounds are boilers, furnaces, heaters, stoves, and fireplaces used to generate heat and/or power in the residential, utility, industrial, and commercial use sectors. A description of combustion sources, typical emission control equipment, and arsenic emission factors for each of these major use sectors is provided in the sections that follow. 4.1.1 Process Descriptions for Utility, Industrial, and Commercial Fuel Combustion Utility Sector Utility boilers bum coal, oil, natural gas, and wood to generate steam for electricity generation. Fossil fuel-fired utility boilers comprise about 72 percent (or 497,000 megawatts [MW]) of the generating capacity of U.S. electric power plants. Of these fuels, coal is the most widely used, accounting for approximately 60 percent of the U.S. fossil fuel-powered electricity generating capacity. Natural gas represents about 25 percent and oil represents the remaining 15 percent. 6 A utility boiler consists of several major subassemblies, as shown in Figure 4-1. 6 These subassemblies include the fuel preparation system, air supply system, burners, the furnace, and the convective heat transfer system. The fuel preparation system, air supply, and burners are primarily involved in converting fuel into thermal energy in the form of hot combustion gases. The last two subassemblies transfer the thermal energy in the combustion gases to the superheated steam that operates the steam turbine and produces electricity. 6 Utility boilers are generally identified by their furnace configuration. Different furnace configurations used in utility boilers include tangentially-fired, wall-fired, cyclone-fired, 4-3 Suparttaatars and Rahaatars Flue Gas Air Figure 4-1. Simplified Boiler Schematic Source: Reference 6. .4-4 ERG_POM_4121 pr* stoker-fired, and fluidized bed combustion (FBC) boilers. Some of these furnace configurations are designed primarily for coal combustion, while others are-also used for oil or natural gas combustion. The furnace types most commonly used for firing oil and natural gas are the tangentially-fired and wall-fired boiler designs. 7 Each of these furnace types is described below. Tangentiallv-fired Boiler --The tangentially-fired boiler is based on the concept of a single flame zone within the furnace. The fuel-air mixture in a tangentially-fired boiler projects from the four comers of the furnace along a line tangential to an imaginary cylinder located along the furnace centerline. When coal is used as the fuel, the coal is pulverized in a mill to the consistency of talcum powder (i.e., so that at least 70 percent of the particles will pass through a 200 mesh sieve), entrained in primary air, and fired in suspension. 8 As fuel and air are fed to the burners, a rotating “fireball” is formed. By tilting the fuel-air nozzle assembly, this “fireball” can be moved up and down to control the furnace exit gas temperature and to provide steam temperature control during variations in load. Tangentially-fired boilers commonly bum pulverized coal. However, oil or gas may also be burned. 6 Wall-fired Boiler — The wall-fired boiler, or normal-fired boiler, is characterized by multiple, individual burners located on a single wall or on opposing walls of the furnace (Figure 4-2). 6 As with tangentially-fired boilers, when coal is used as the fuel it is pulverized, entrained in primary air, and fired in suspension. In contrast to tangentially-fired boilers that produce a single flame zone, each of the burners in a wall-fired boiler has a relatively distinct flame zone. Various wall-fired boiler types exist, including single-wall, opposed-wall, cell, vertical, arch, and turbo. Wall-fired boilers may bum pulverized coal, oil, or natural gas. 6 Cvclone-fired Boiler --In the cyclone-fired boiler, fuel and air are burned in horizontal, cylindrical chambers, producing a spinning, high-temperature flame. Cyclone-fired boilers are almost exclusively crushed coal-fired. The coal is crushed to a 4-mesh size and admitted with the primary' air in a tangential fashion. The finer coal particles are burned in suspension, while the coarser particles are thrown to the walls by centrifugal force. 7 Some units are also able to fire oil and natural gas. 6 4-5 Burner B Burner A Burner D Burner C Figure 4-2. Single Wall-Fired Boiler Source: Reference 6. 4-6 ERO_POM_4122 pr« Fluidized Bed Combustion Boiler -Fluidized bed combustion is a newer boiler technology that is not as widely used as the other, more conventional boiler types. In a typical FBC, crushed coal in combination with inert material (sand, silica, alumina, or ash) and/or sorbent (limestone) are maintained in a highly turbulent suspended state by the upward flow of primary air (Figure 4-3). This fluidized state promotes uniform and efficient combustion at lower furnace temperatures, between 1,575 and 1,650°F, compared to 2,500 and 2,800°F for conventional coal-fired boilers. Fluidized bed combustors have been developed to operate at both atmospheric and pressurized conditions. 6 Stoker-fired Boiler —Instead of firing coal in suspension as in the boilers described above, the mechanical stoker can be used to bum coal in fuel beds. Mechanical stokers are designed to feed coal onto a grate within the furnace. The most common stoker type used in the utility industry is the spreader stoker (Figure 4-4). 6 In the spreader stoker, a flipping mechanism throws crushed coal into the furnace and onto a moving fuel bed (grate). Combustion occurs partly in o suspension and partly on the grate. Emission Control Techniques —Utility boilers are highly efficient and among the best controlled of all combustion sources. Existing emission regulations for total PM have necessitated controls on coal- and oil-fired utility sources. Emission controls are not required on natural gas boilers because, relative to coal and oil units, uncontrolled emissions are inherently low. 9 Baghouses. electrostatic precipitators (ESPs), wet scrubbers, and multicyclones have been used to control PM in the utility sector. As described in other source category sections, arsenic condenses on PM, which is easily controlled by PM control technologies. Particulate arsenic, specifically fine particulate, is controlled most effectively by baghouses or ESPs. Depending on their design, wet scrubbers are potentially effective in controlling particulate arsenic. Multicyclones are less effective at capturing fine particles of arsenic and, therefore, are a poor control system for arsenic emissions. 10 A more recently applied S0 2 control technique for utility boilers is spray drying. In this process, the gas stream is cooled in the spray dryer, but it remains above the saturation temperature. A fabric filter or an ESP is located downstream of the spray dryer, thus controlling 4-7 Rue Gas Figure 4-3. Simplified Atmospheric Fluidized Bed Combustor Process Flow Diagram Source: Reference 6. 4-8 ERG POM 4124.ds4 4-9 Figure 4-4. Spreader Type Stoker-Fired Boiler both particulate and vapor-phase arsenic compounds that condense before they reach the baghouse or ESP. 9,10 Industrial/Commercial Sector Industrial boilers are widely used in manufacturing, processing, mining, and refining, primarily to generate process steam, electricity, or space heat at the facility. Only a limited amount of electricity is generated by the industrial sector; only 10 to 15 percent of industrial boiler coal consumption and 5 to 10 percent of industrial boiler natural gas and oil consumption are used for electricity generation. 11 Commercial boilers are used to provide space heating for commercial establishments, medical institutions, and educational institutions. Industrial boiler use is concentrated in four major industries: paper products, chemical products, food, and petroleum. The most commonly used fuels include natural gas, distillate and residual fuel oils, and coal in both crushed and pulverized form. 11,12,13 Other fuels burned in industrial boilers are wood wastes, liquified petroleum gas, and kerosene. Wood waste is the only non-fossil fuel discussed here since few arsenic emissions are attributed to the combustion of liquified petroleum gas and kerosene. The burning of wood waste in boilers is confined to those industries where it is available as a by-product. It is burned both to obtain heat energy and to alleviate possible solid waste disposal problems. Generally, bark is the major type of wood waste burned in pulp mills. In the lumber, furniture, and plywood industries, either a mixture of wood and bark, or wood alone, is frequently burned. As of 1980, the most recent data identified, there were approximately 1,600 wood-fired boilers operating in the United States with a total capacity of over 100,000 million Btu/hr (30,000 MW thermal). 12 Many of the same boiler types used in the utility sector are also used in the industrial/commercial sector; however, the average size boiler used in the industrial/ commercial sector is substantially smaller than the average size boiler used in the utility sector. In addition, a few boiler designs are used only by the industrial/commercial sector. For a general description of .4-10 the major subassemblies and key thermal processes that occur in boilers, refer to Figures 4-1 to 4-4 in the section on Utility Sector Process Description and the accompanying discussion. Stoker-Fired Boiler -Instead of firing coal in suspension (like the boilers described in the Utility Sector Process Description section), mechanical stokers can be used to bum coal in fuel beds. All mechanical stokers are designed to feed coal onto a grate within the furnace. The most common stoker types in the industrial/commercial sector are overfeed and underfeed stokers. In overfeed stokers, crushed coal is fed from an adjustable grate above onto a traveling or vibrating grate below. The crushed coal bums on the fuel bed as it progresses through the furnace. Conversely, in underfeed stokers, crushed coal is forced upward onto the fuel bed from below by mechanical rams or screw conveyors. 6,8 Water-tube BoiIers --In water-tube boilers, water is heated as it flows through tubes surrounded by circulating hot gases. These boilers represent the majority (i.e., 57 percent) of industrial and commercial boiler capacity (70 percent of industrial boiler capacity). 11 Water-tube boilers are used in a variety of applications, from supplying large amounts of process steam to providing space heat for industrial and commercial facilities. These boilers have capacities ranging from 9.9 to 1,494 million Btu/hr (2.9 to 439.5 MW thermal), averaging about 408 million Btu/hr (120 MW thermal). The most common types of water-tube boilers used in the industrial/commercial sector are wall-fired and stoker-fired boilers. Tangentially-fired and FBC boilers are less commonly used. 13 Refer to Figures 4-1 to 4-4 and the accompanying discussion in the section on Utility Sector Process Description for more detail on these boiler designs. Fire-tube and Cast Iron Boilers --Two other heat transfer methods used in the industrial/commercial sector are fire-tube and cast iron boilers. In fire-tube boilers, hot gas flows through tubes that are surrounded by circulating water. Fire-tube boilers are not available with capacities as large as water-tube boilers, but they are also used to produce process steam and space heat. Most fire-tube boilers have a capacity between 1.4 and 25 million Btu/hr (0.4 to 7.3 MW thermal). Most installed fire-tube boilers bum oil or gas and are used primarily in commercial/institutional applications. 4-11 In cast iron boilers, the hot gas is also contained inside the tubes that are surrounded by the water being heated, but the units are constructed of cast iron instead of steel. Cast iron boilers are limited in size and are used only to supply space heat. Cast iron boilers range in size from less than 0.34 to 9.9 million Btu/hr. 13 Wood Waste Boilers --The burning of wood waste in boilers is primarily confined to those industries where it is available as a by-product. Wood is burned both to obtain heat energy and to alleviate solid waste disposal problems. Wood waste may include large pieces such as slabs, logs, and bark strips as well as cuttings, shavings, pellets, and sawdust. 12 Various boiler firing configurations are used to bum wood waste. One configuration that is common in smaller operations is the dutch oven or extension-type of furnace with a flat grate. This unit is used widely because it can bum very high-moisture fuels. Fuel is fed into the oven through apertures in a firebox and is fired in a cone-shaped pile on a flat grate. The burning is accomplished in two stages: (1) drying and gasification, and (2) combustion of gaseous products. The first stage takes place in a cell separated from the boiler section by a bridge wall. The combustion stage takes place in the main boiler section. 12 In another type of boiler, the fuel-cell oven, fuel is dropped onto suspended fixed grates and is fired in a pile. The fuel cell uses combustion air preheating and positioning of secondary and tertiary air injection ports to improve boiler efficiency. 12 In many large operations, more conventional boilers have been modified to bum wood waste. These modified units may include spreader stokers with traveling grates or vibrating grate stokers, as well as tangentially-fired or cyclone-fired boilers. Refer to Figures 4-1 to 4-4 and the accompanying discussion in the section on Utility Sector Process Description for more detail on these types of boilers. The spreader stoker, which can bum dry or wet wood, is the most widely used of these configurations. Fuel is dropped in front of an air jet that casts the fuel out over a moving grate. The burning is carried out in three stages: (1) drying, (2) distillation and burning of volatile matter, and (3) burning of fixed carbon. These operations often fire natural gas or oil 4-12 as auxiliary fuel. Firing an auxiliary fuel helps to maintain constant steam when the wood supply fluctuates or to provide more steam than can be generated from the wood supply alone. 12 Sander dust is often burned in various boiler types at plywood, particle board, and furniture plants. Sander dust contains fine wood particles with a moisture content of less than 20 percent by weight. The dust is fired in a flaming horizontal torch, usually with natural gas as an ignition aid or as a supplementary fuel. 12 A recent development in wood-firing is the FBC (refer to Figures 4-1 to 4-4 and the accompanying discussion in Utility' Sector Process Description for more detail on this boiler t\pe). Because of the large thermal mass represented by the hot inert bed particles, FBCs can handle fuels with high moisture content (up to 70 percent, total basis). Fluidized bed combustors can also handle dirty fuels (up to 30 percent inert material). Wood material is pyrolyzed faster in a fluidized bed than on a grate due to its immediate contact with hot bed material. 12 The composition of wood w-aste is expected to have an impact on arsenic emissions. The composition of wood waste depends largely on the industry from which it originates. Wood waste fuel can contain demolition debris like plastics, paint, creosote-treated wood, glues, synthetics, wire, cable, insulation, and so forth, which are potential sources of arsenic emissions. Pulping operations, for example, produce great quantities of bark along with sand and other noncombustibles. In addition, when fossil fuels are co-fired with wood waste, there is potential for additional arsenic emissions from the arsenic content of the fossil fuel. 14 Waste Oil Combustion —Waste oil is another type of fuel that is burned primarily in small industrial/commercial boilers and space heaters. Space heaters (small combustion units generally less than 250,000 Btu/hr heat input) are common in automobile service stations and automotive repair shops where supplies of waste crankcase oil are available. 15 Waste oil includes used crankcase oils from automobiles and trucks, used industrial lubricating oils (such as metal working oils), and other used industrial oils (such as heat transfer fluids). Due to a breakdown of the physical properties of these oils and contamination by other materials, these oils are considered waste oils when they are discarded. 16 4-13 The Federal government has developed regulations for waste oil fuel under the Resource Conservation and Recovery Act (RCRA). The EPA has determined that as long as used oil is recycled (which includes burning it for energy recovery as well as re-refining it or other processes), it is not considered a hazardous waste under RCRA. 17 However, if a facility does bum used oil, that facility is subject to certain requirements under RCRA. EPA has established two categories of waste fuel: “on-specification” and “off-specification.” If the arsenic levels of the waste oil are 5 ppm or less, the waste oil is classified as “on-specification;” if the arsenic levels are greater than 5 ppm, the waste oil is classified as “off-specification”. 18 If a facility is burning “on-specification” waste oil for energy recovery, that facility is only subject to certain reporting and recordkeeping requirements. 18 If a facility bums the waste oil in a space heater with heat input capacity less than 0.5 million Btu/hr and vents the exhaust to the ambient air, then that facility is not subject to any requirements. 19 A facility burning “off-specification” waste oil for energy recovery must comply with additional requirements, including verification to EPA that the combusted oil was not mixed with 90 other hazardous wastes. Boilers designed to bum No. 6 (residual) fuel oils or one of the distillate fuel oils can be used to bum waste oil, with or without modifications for optimizing combustion. As an alternative to boiler modification, the properties of waste oil can be modified by blending it with fuel oil to the extent required to achieve a clean-burning fuel mixture. Coal Combustion -A very small amount of coal is used in the industrial/ commercial sector. Coal accounts for only 18 percent of the total firing capacity of fossil fuel used. The majority of coal combustion occurs in the utility sector. Refer to Figures 4-1 to 4-4 and the accompanying discussion in Utility Sector Process Description for more detail about these boiler types. 4-14 *9 Emission Control Tcchniques -The amount of arsenic emissions from industrial/ commercial boilers depends primarily on two factors: (1) the type of fuel burned, and (2) the type of boiler used. The secondary influences on arsenic emissions are the operating conditions of the boiler and the APCD used. Emission controls for industrial boilers and their effectiveness in reducing arsenic emissions are very similar to those previously described for utility boilers. PM control in the industrial sector is achieved with baghouses, ESPs, wet scrubbers, and multicyclones. PM emissions from oil-fired industrial boilers generally are not controlled under existing regulations because emission rates are low. Some areas may limit S0 2 emissions from oil-firing by specifying the use of lower-sulfur-content oils. Natural gas-fired industrial boilers are also generally uncontrolled because of very low emissions. 9,10 Wood-fired industrial boilers are typically controlled by multicyclones followed by venturi or impingement-type wet scrubbers for PM control. Some wood-fired boilers use ESPs for PM control. The effect of both control systems on arsenic emissions reduction is estimated to be similar to that obtained at coal-fired units using the same technology (i.e., potentially good PM and vaporous arsenic control with scrubbers, and effective PM arsenic control but no vaporous arsenic control with ESPs). 9,10 4.1.2 Emission Factors for Utility, Industrial, and Commercial Fuel Combustion Extensive arsenic emissions data for utility, industrial, and commercial stationary external combustion sources are available in the literature. Because State and Federal air pollution regulations often require emissions testing for toxic air pollutants, a significant current database of arsenic emissions from these fuel combustion sources exists. 4-15 Emission factors for utility, industrial, and commercial stationary external combustion source categories, grouped according to the type of fuel burned, are presented in Tables 4-1 to 4-12 and discussed under the following subheadings: • Wood waste combustion: -- Utility boilers (Table 4-1), -- Industrial boilers (Table 4-2), -- Commercial/institutional boilers (Table 4-3); • Coal combustion: -- Utility boilers (Table 4-4), -- Industrial boilers (Table 4-5), — Commercial/institutional boilers (Table 4-6); • Oil combustion: — Utility boilers (Table 4-7), — Industrial boilers (Table 4-8), — Commercial/institutional boilers (Table 4-9); • Waste oil combustion: - Industrial boilers (Table 4-10), - Commercial/institutional boilers (Table 4-11); and • Solid waste combustion: -- Utility boilers (Table 4-12). 4-16 Wood Waste Combustion Arsenic emission factors for wood waste combustion in utility, industrial, and commercial boilers are presented in Tables 4-1,4-2, and 4-3, respectively. A general uncontrolled emission factor in units of lb per ton of wood waste combusted on wet, as-fired basis of 50 percent moisture and 4,500 Btu/lb is given in each table. These emission factors are widely applicable to all utility, industrial, and commercial wood waste combustion SCC categories. 6 However, a wide range of boiler sizes, boiler and control device configurations, and fuel characteristics are reflected by these composite emission factors. For this reason, if site-specific information is available to characterize an individual combustion source more accurately, it is recommended that the reader locate the appropriate process-specific emission factor presented in the applicable table. The average emission factors for utility wood waste-fired boilers are presented in Table 4-1. ’ The emission factors represent a range of control configurations and wood waste 12 compositions. Average emission factors for industrial wood waste-fired boilers are presented in Table 4-2. 12 -22.23.24,25,26.27 ^ portion of emission factors included are based on a comprehensive toxic air emission testing program in California. The summarized results of the study were used to obtain the average arsenic emission factors. The emission factors represent a range of boiler designs and capacities, control configurations, and wood waste compositions. The study, conducted by the Timber Association of California (TAC), tested boiler types with capacities greater than 50,000 lb of steam per hour, including fuel cell, dutch oven, stoker, air injection, and fluidized bed combustors. The range of control devices represented in the sample set included multiple cyclones, ESPs, and wet scrubbers 22,23,25 Wood waste-fired commercial/institutional boilers average emission factors are presented in Table 4-3. 12 These emission factors represent uncontrolled configurations and a range of wood waste compositions. 12 Many of the same emission factors can be found in the utility and 4-17 TABLE 4-1. ARSENIC EMISSION EACTORS POR WOOD WASTE-FIRED UTILITY BOILERS 4) O c OC oo c .S .o « d, on •a >-n E © UJ o TO u. OJ oo I— c*0 O C O 2 re U- £ © c o •— E UJ u TO u. .2 c On C on — UJ CO re t— o > < u CJ > u C c o U o © x © rr W") © x © 00 00 OJ c c •o 2J re E « 2 "© on O re > £ t x r= oj > CD U. n © x © oo 00 4> c o z fS © X 3 Pi <5 -J e o I •« oo jg o S X x w-> — *n oo 2 co c _o 1 £ r> l © X oo •o *8 2 .§ E u - ' T3 - 2 c/j O eo > £ £ ■p i— 5 jy 2 o > CO m © wo © >> X >0 !s* *w i •> "S' OO .X c o I s. 00 JX > c o o H •o 2 on 3 X E o u 1> 4 a* on re e o 1) a. •a k> re on k. O o 2 c o on on UJ 2 £ o *C x re U. U. u. 4-18 TABLE 4-2. ARSENIC EMISSION FACTORS FOR WOOD WASTE-FIRED INDUSTRIAL BOILERS d o c CD ka ,. o © X © ■'T o cs tU 3 « .2 c VO O vo — E tU D 60 re i_ d > < © X © 00 00 v-i © X © 00 00 3 m c ,o 1 X w-i © X © «n cs 3 ffl C o VO © X © (N 3 ffl C o 2 X © 3 ffi C 1 X r~ © x © (N ■vf V V> © X o 00 00 VI © X © 00 00 «/■> © X © 00 00 a o u D E 3 "•5 CD 2 3 o 5 ID C o z £ X 2 DO D £ >v u c D D © Va- tU D £ g 1 .2 ^ o S D D C _o o c* ' >, .3 V- U £ 3 D X — X 3 Cl. vo t. *2 > DO s E >v CD 3 D tu 3 1 g *3 if "o D &cc U .= « IS Q. >v 2 tu 3 0- O DO •S tu * o D *2 C U O D ">v ‘C 1 U D D OC s-s X P8 3 -b 2 tt. D C o Z D 3 o Z D 3 o Z D U i— 3 O DO C _o C/5 VO E tu QJ 02 D D X D X E 3 z u u DO © I Os (N © fS o I Os Cd oo B -S C CO in 0£ C/5 UJ o re u. 0) oo c <0 l— ro 2 S u 2 £ £ I s C/1 C/5 £ uu o re U. c .2 C c/5 O c/5 — £ 2 lu = QJ "" OO re u- U > < u o > 4J Q c o U VO cs I— 3 o m m m £ CD U £ U £ in s 2 3 2 C _o 1 x >/■> © X O 3 o II O QJ o '.S' u - 2 re 3. 3 u. 3 rs i— — rs U D »r> i O T O X 8 X 3 X s m c o o TT © X o 00 oo ©. X TT m V U c o Z O m — re 3 X) o Jr oo « a, 2? Cj 0> c 2 .2 § C/5 I— C/5 DO E O “ c . 4> •o > OJ c t? o 3 « £ O E H o ° ai w 3 g > ^ OO •o _c O re > QJ *- i 8. <2 2 3 ^ O (U •5 «> m re > re UU O re o 0> t- CU o re To O u. O JL> w a. oo U 4-20 TABLE 4-3. ARSENIC EMISSION EACTORS EOR WOOD WASTE-FIRED COMMERCIAL/INSTITUTIONAL BOILERS u OS CD of s O OS a * cd 4> Of) C 03 OC lx ra o e o 2 re "i: CD £ C _o on 05 E CD u re .2 e O<3 o on w ’= 3 SJ Cfi re aj > < u u > u o c o U OJ U i— 3 O C/3 C _o on on CD iS E 3 2 U U c/3 U U U T © K o TT (N sO b X O TT © X o TT rs SO o X O TT V © K o ■'T (N 9 © *x o b © o X X X O o o oo oo oo 00 00 oo D 9J 4> zz c c 0 o o 2 2 2 jj 'c CO •o o lx CD JL[ 'o 00 JJ 'o 00 ffi Vi £ UJ tu tu UJ UJ UJ UJ UJ UJ UJ UJ 04 oo £ ™ co 3 ffi M u. m o c o .2 co — = ! .2 15 C/5 “ .52 e E UJ s o T o X o TT PS c z T © ’x PS vi y © X 3 ps X m O T © x PS ■ C Vi -S f" — 3 •= UJ ,3 04 15 oo — 2 .E 04 > < 3 o T © x c o y © x oo m v~i y © x 00 vd T o x *n T O x 00 m V) y © x TT oo vb y © x *n c u i— 3 E > c ^ U Q 04 04 04 - 04 04 04 04 04 04 04 3 3 3 3 3 3 3 3 c 3 C O O O O O O O o C Z Z z Z Z Z Z Z Z Z 04 04 ka 3 O 140 C c tSi vi E UJ CO 3 O co u 04 o oo c CO UC k- J= > 3 co E— i_ < H 1— £ Q ka co O £ co O Q co O "co o O *C0 UJ " o c/5 vs 3 O CO O U vs 3 O o U vs 3 O CO E vs 3 O 04 4* O 04 £ vs 3 O _s •a 04 N ‘ka E (A 3 O 3 •o 04 N ‘k. B V) 3 O 3 3 U. 04 3 vs 3 O s $5 u 04 •o vs 3 O C \J oo .3 04 3 04 > o E 3 04 > o a _o "o 1 co 04 ka § 04 > CO ka 04 > 15 .© 04 > o 15 X 5 04 > © 15 a© 04 15 .© CO 04 ka o 5 2 o m ffi 1 © m s U m Ck C/5 5 ka H o 3 C/5 2 o ffi 3 C/5 £ o ffi 3 C/5 u 3 C/1 Ck C/5 04 4= E 3 z u u oo (N O © PS PS © 8 ro © i PS s PS PS m PS PS PS PS PS PS PS PS 8 8 8 8 © © © © 4-23 TABLE 4-4. CONTINUED cj o c CJ ka A) t*—. 0) a: 00 ON CN ON fS On . £> _>N a. 3 E \o © "Sb o CJ > C o o o H •o cj oo 3 E o u "re o o <4— O 3 ffl C o ■ 8 . •a < c u h .2 c > c ^ U Q ro © X cn r~ CN ro o x Os m OJ c cj c o Z cj c o Z 4> O 4> C C C O O O Z Z Z c 5 Cj -X O "re O "re 0 > w E 0 U 4 J ‘E o> 'C OJ > E 0 U o> ‘E « c 0 U CJ ‘E CO .5 "w > t" ka CJ U I) 4-* 'E ka CJ •0 re CJ X. 3 CO re H > O CO J 5 0 CD co J 2 0 CQ 00 J CJ >v U co J re ha H > g CO J ka Q. CO a E 3 Z u u on >0 rJ m O 3 8 rj m m cn rn 1 m 8 8 8 8 8 8 — 1 O 1 O O O O 0 4-24 TABLE 4-5. ARSENIC EMISSION FACTORS EOR COAL EIRE!) 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CJ « CQ 4> © r4 on r* 00 2} n 2 © © O © © O © (S r» 3 r4 r4 rJ ri n n n r> z 8 8 8 8 8 8 8 8 8 u • i m m m r O. 3 2 DO 2L •a 4> 2 4) 8 C«— O X to 4» co CO 4> c_ o. X 4) 4> i~ TO CO ba O u if? Ct— c _o 00 CO ta 4-27 means data not available. TABLE 4-7. ARSENIC EMISSION FACTORS FOR OIL-FIRED UTILITY BOILERS 1) O c X CO ~ « c 4 J > < CJ > o Q c o U o oo C _o c/5 to E UJ o X E 3 2 U U C/3 ro Tt ro UJ T O X TT vi O VI o *x Ti¬ en SO NO o X o OS v o X © C4 OJ c o 2 c c to •— O -I o o 3 .!= E £ OS ■o OJ re 3^_ rE £> «3 • — 4J o OS CQ m m UJ T © X '<3- v o o c o 2 •o OJ 3 °k. TJ 5 “ O OS 00 ro po U NO o x o rs aj 3 O 2 CO N X TL 3 E 8 . ■8 0> w I J3 1 Cm O X FT . M • —■ IM .2 o O O E o o o UJ 2 2 2 m jo o a is X _re "re > re o c re re •o 4) E 4-28 TABLE 4-8. ARSENIC EMISSION FACTORS FOR OIL-FIRED INDUSTRIAL BOILERS o uu OC C -S % cS CO UJ u w 0) oo * i o c t> .2 C3 — u- •■= c E .2 x to — c E UJ T O x T © cj w ™ u. = c ca .2 c to O oo -JjS E -"E uj E 4J X! OO —' 2 .E y > < X o CN CJ O o U cu c c Z cj c o Z cj CJ 1— 3 C CO c _o to r— c UJ O (N •a O „ \o < O U 04 u I— 3 c 00 c o o C/5 C/5 £ UJ re 3 .32 u 02 o VC 04 •o re k. O ta vC b X O C4 •'T 04 c c Z o fN — T3 O re 22 — 1 re v — 04 £ re 5 o «/0 m O i PO ro 04 o c 04 t— ,04 04 02 44 U u. 3 O U2 _04 X> _re "re > re o c re CO X3 0/5 1 04 E £ f I I 3 4-30 TABLE 4-10. ARSENIC EMISSION FACTORS FOR WASTE OIL-FIRED INDUSTRIAL BOILERS O 03 U. M C c -5 O CT3 co CC CO u 44 o > 44 Q c o U 44 U b> 3 o c _o 'v> © m O «r> 44 44 c 44 h> ,44 44 o£ 44 44 u. 3 O C/3 a oo •X 44 > S o 44 o H •o 44 3 •O '5 44 "33 a ■o 44 E 44 a V- O JD ■a 44 CO CO 44 l. Cl X 44 44 c- C0 CO L> O 44 .03 jy £> J2 <3 > 03 C c to TO •o £ 4-31 TABLE 4-11. ARSENIC EMISSION FACTORS FOR WASTE OIL-FIRED COMMERCIAL/INSTITUTIONAL BOILERS u CB tU M = -s o cB ‘tn CC CO U m Z u u on Q O CM o X o — VO X O vn CN u a> OJ 3 r- C C c o Z Z Z 4> C i— CO b. ■o • # # . # O O o u © aj OJ Xn F CO CB 03 k— 03 £ £ 3 m £ 4J U c 0 © c u > c o u H •o © c u. 3 •D ‘o OJ CO CB Z a u- O X) T3 4J n w 4> l_ a. x Q a> u. CB CO u. O X5 CB ‘cB > CB w o c CB CB CN o m nr u CB T3 CO ro © CN 8 CN 8 cc c .o CO o CN § r— 1 m i un i ii o CO o E O O o u c £ i 1 1 3 O UJ X! 1 | on 4-32 Solid Waste Combustion Arsenic emission factors for solid-waste fired utility boilers are presented in Table 4-12. 36 The only control configuration represented is an ESP. Additional data regarding emissions from combustion of refuse derived fuel may be available from the Electric Power Research Institute (phone 415-855-2000) in Report No. TR104614. 4.1.3 Source Locations Fuel economics and environmental regulations affect regional use patterns for combustion sources. Most of the U.S. utility coal-firing capability is east of the Mississippi River, with the significant remainder being in the Rocky Mountain region. Natural gas is used primarily in the South Central States and California. Oil is predominantly used in Florida and the Northeast. Information on precise utility plant locations can be obtained by contacting utility trade associations, such as the Electric Power Research Institute in Palo Alto, California, the Edison Electric Institute in Washington, D.C. (202-828-7400), or the U.S. Department of Energy (DOE) in Washington, D.C. Publications by EPA and DOE on the utility industry are useful in determining specific facility locations, sizes, and fuel use. Industrial and commercial coal combustion sources are located throughout the United States, but tend to be concentrated in areas of industry and larger population. Most of the coal-fired industrial boiler sources are located in the Midwest, Appalachian, and Southeast regions. Industrial wood-fired boilers tend to be located almost exclusively at pulp and paper, lumber products, and furniture industry facilities. These industries are concentrated in the Southeast, Gulf Coast, Appalachian, and Pacific Northwest regions. Trade associations such as the American Boiler Manufacturers Association in Arlington, Virginia (703-522-7350) and the Council of Industrial Boiler Owners in Fairfax Station, Virginia (703-250-9042) can provide on oo information on industrial boiler locations and trends. ’ 4-33 TABLE 4-12. ARSENIC EMISSION FACTOR FOR SOLID WASTE-FIRED UTILITY BOILERS Ui o o w UL. M c -S O TO P 'S5 065 C/3 E w o> oo T 3 O cd cc X o u- erj C C TT r; o i- n CJ w CG —■ tt. £ g e © C/2 X CO © c rs G UJ CO U- c CJ cc U- .3 C «/5 o o • — X zz “ "—■* oo c Cj vd CJj rc u. CJ > < CJ > CJ /—s c- _ on o UJ G o U u u Urn 3 O on c a> o C/} ca cn CO £ E TD uj o on i— t; ji E 3 © i z « Cl. "c3 U OJ > u* O. o o c « a a—* to O ■a H o UJ E II £ 1 CL. l on 3 UJ .4-34 4.2 Hazardous Waste Incineration Hazardous waste, as defined by RCRA in 40 CFR Part 261, 17 includes a wide variety of waste materials. Hazardous wastes are produced in the form of liquids (e.g., waste oils, halogenated and nonhalogenated solvents, other organic liquids, and pesticides/herbicides) and sludges and solids (e.g., halogenated and nonhalogenated sludges and solids, dye and paint sludges, resins, and latex). The arsenic content of hazardous waste varies widely, but arsenic could be emitted from the incineration of any of these types of hazardous waste. Based on a 1986 study, total annual hazardous waste generation in the United States was approximately 292 million tons. 39 Only a small fraction of the waste (less than 1 percent) was incinerated. In addition, the U.S. EPA has scheduled rulemaking to develop MACT standards for hazardous . waste combustors and cement kilns. The proposed standard should reduce arsenic emissions and is scheduled to be promulgated no later than 2000. Based on an EPA study conducted in 1983, the major types of hazardous waste streams incinerated were spent nonhalogenated solvents and corrosive and reactive wastes contaminated with organics. Together, these accounted for 44 percent of the waste incinerated. Other prominent wastes included hydrocyanic acid, acrylonitrile bottoms, and nonlisted ignitable 40 wastes. Industrial kilns, boilers, and furnaces are used to bum hazardous waste. They use the hazardous waste as fuel to produce commercial products such as cement, lime, iron, asphalt, or steam. In fact, the majority of hazardous waste generated in the United States is currently disposed of in cement kilns. Hazardous waste, which is an alternative to fossil fuels for energy and heat, is used at certain commercial facilities as a supplemental fuel. In the process of producing energy and heat, the hazardous wastes are subjected to high temperatures for a sufficient time to volatilize metals in the waste. 4-35 4.2.1 Process Description Hazardous waste incineration employs oxidation at high temperatures (usually 1,650°F or greater) to destroy the organic fraction of the waste and reduce volume. A diagram of the typical 39 process component options in a hazardous waste incineration facility is provided in Figure 4-5. The diagram shows the major subsystems that may be incorporated into a hazardous waste incineration system: waste preparation and feeding, combustion chamber(s), air pollution control, and residue/ash handling. Five types of hazardous waste incinerators are currently available and in operation: liquid injection, rotary kiln, fixed-hearth, fluidized-bed, and fume injection. 41 Additionally, a few other technologies have been used for incineration of hazardous*waste, including ocean incineration vessels and mobile incinerators. These latter processes are not in widespread use in the United States and are not discussed below. Liquid Injection Incinerators Liquid injection combustion chambers are used for pumpable liquid waste, including some low-viscosity sludges and slurries. Liquid injection units are usually simple, refractory-lined cylinders (either horizontally or vertically aligned) equipped with one or more waste burners. The typical capacity of liquid injection units is about 8 to 28 million Btu/hour. Figure 4-6 presents a schematic diagram of a typical liquid injection unit. 39,41 Rotary Kiln Incinerators Rotary kiln incinerators are used for destruction of solid wastes, slurries, containerized waste, and liquids. Because of their versatility, these units are most frequently used by commercial off-site incineration facilities. Rotary kiln incinerators generally consist of two combustion chambers: a rotating kiln and an afterburner. The rotary kiln is a cylindrical refractory-lined shell mounted on a slight incline. The primary function of the kiln is to convert solid wastes to gases, which occurs through a series of volatilization, destructive distillation, and 4-36 Waste Preparation Combustion Air Pollution Control c 35 ®2 _raox 3 _j£Tu_ li¬ ra n c c_ = ra i S «- J ® 5 N ® « E= 3 if-si ffi -C .3 ® DUWW c o — ^ ^ ® Ec>®o O m ® H 3 ® ;HOit ® r ejsuM •■i o ® ra I#!! C ® fe O S> wo. o> |I3I N O 7 _® CL t— OUJ II II II 5 COO-P- > <0 O _ LLI CL o\ m v o c u k— <5 u QJ o l_ 3 O 00 4-37 Figure 4-5. Typical Process Component Options in a Hazardous Waste Incineration Facility 4-38 partial combustion reactions. The typical capacity of these units is about 10 to 60 million Btu/hour. Figure 4-7 presents a schematic diagram of a typical rotary kiln unit. 39 An afterburner is connected directly to the discharge end of the kiln. The afterburner is used to ensure complete combustion of flue gases before their treatment for air pollutants. A tertiary combustion chamber may be added if needed. The afterburner itself may be horizontally or vertically aligned, and functions on much the same principles as the liquid injection unit described above. Both the afterburner and the kiln are usually equipped with an auxiliary fuel-firing system to control the operating temperature. Fixed-Hearth Incinerators Fixed-hearth incinerators (also called controlled-air, starved-air, or pyrolytic incinerators) are the third major technology used for hazardous waste incineration. 39 Figure 4-8 presents a schematic diagram of a typical fixed-hearth unit. 39,41 This type of incinerator may be used for the destruction of solid, sludge, and liquid wastes. Fixed-hearth units tend to be of smaller capacity (typically 5 million Btu/hour) than liquid injection or rotary kiln incinerators because of physical limitations in ram feeding and transporting large amounts of waste materials through the combustion chamber. Fixed-hearth units consist of a two-stage combustion process similar to that of rotary kilns. Waste is ram-fed into the primary chamber and burned at about 50 to 80 percent of stoichiometric air requirements. This starved-air condition causes most of the volatile fraction to be destroyed pyrolitically. The resultant smoke and pyrolysis products pass to the secondary chamber, where additional air and, in some cases, supplemental fuel, is injected to complete the combustion. 39 4-39 Os r*o o c_> c 4J l— £ QJ a: o c k. £ V G£ o u l_ 3 o c /2 4-41 Fluidized-Bed Incinerators Fluidized-bed incinerators (combustors), which are described in Section 4.4.1 of this report, have only recently been applied to hazardous waste incineration. FBCs used to dispose of hazardous waste are very similar to those used to incinerate sewage sludge except for their additional capability of handling liquid wastes. FBCs are suitable for disposing of combustible solids, liquids, and gaseous wastes. They are not suited for irregular or bulky wastes, tarry solids, or other wastes that leave residues in the bed 42 Fluidized-bed combustion chambers consist of a single refractory-lined combustion vessel partially filled with inert granular material (e.g., particles of sand, alumina, and sodium carbonate). 39 The typical capacity of this type of incinerator is 45 million Btu/hour. Fume Injection Incinerators Fume injection incinerators are used exclusively to destroy gaseous or fume wastes. The combustion chamber is comparable to that of a liquid-injection incinerator (Figure 4-6) in that it usually has a single chamber, is vertically or horizontally aligned, and uses nozzles to inject the waste into the chamber for combustion. Waste gases are injected by pressure or atomization through the burner nozzles. Wastes may be combusted solely by thermal or catalytic oxidation. Emission Control Techniques The types of incinerators used for hazardous waste combustion are similar to the incinerators used by the other combustion sources discussed earlier in this section. However, the components in the hazardous waste stream vary extensively. The hazardous waste stream may include a variety of liquid, solid, or sludge wastes considered hazardous by RCRA. The hazardous waste stream may also include wastes generated by a variety of sources (e.g., medical, municipal, and sewage sludge). 4-42 Controlling arsenic emissions is partly accomplished by monitoring the temperature of the combustion bed. Arsenic compounds vaporize at elevated temperatures. The higher the temperature, the larger the fraction of arsenic vaporized. As the temperature drops, a fraction of the arsenic condenses. Collection of arsenic condensed on PM occurs in the APCD. 43 4.2.2 Emission Factors The composition of the hazardous waste varies tremendously in the hazardous waste incineration industry, such that the arsenic content of the waste stream also varies widely. The arsenic content of the waste being combusted dictates whether or not significant arsenic emissions occur. One emission factor for arsenic is reported in Table 4-13. 44 Additional emission factor data are not readily available. However, relevant test data may be available in Volume II of the draft Technical Support Document for the Hazardous Waste Combustion Rule (February 1996). Also, emission factor data may be available in databases developed by trade associations or other industry groups. 45 4.2.3 Source Location Currently, 162 permitted or interim status incinerator facilities, having 190 units, are in operation in the U.S. Another 26 facilities are proposed (i.e., new facilities under construction or permitting). Of the above 162 facilities, 21 facilities are commercial facilities that bum about 700,000 tons of hazardous waste annually. The remaining 141 are on-site or captive facilities and bum approximately 800,000 tons of waste annually. 4-43 TABLE 4-13. ARSENIC EMISSION FACTORS FOR HAZARDOUS WASTE INCINERATION o a -S s — 1 O (Q "55 OC n UJ OO cj rt UJ C o oo UJ cj w UJ c _o 'on C/3 UJ a> CJO « 1— < T © X C4 ro so C/3 1— 3J Xl X 5 CJ C/5 "3 o cj t— 3 O C/3 c _o * C/3 C/3 E UJ 4J X E 3 2 U U C/3 aj C/3 rt £ Cfl 3 C T3 i— CTJ 3 8 i 5 aj CJ c u CJ a: u b-i 3 O C/3 4-44 43 Municipal Waste Combustion 4.3.1 Process Description Municipal waste combustors (MWCs) bum garbage and other nonhazardous solid waste, commonly called municipal solid waste (MSW). Three main types of combustors are used to combust MSW: mass bum, refuse-derived fuel-fired (RDF), and modular. Each type is discussed below. Mass Bum Combustors In mass bum units, MSW is combusted without any preprocessing other than removal of items too large to go through the feed system. In a typical mass bum combustor, refuse is placed on a grate that moves through the combustor. Combustion air in excess of stoichiometric amounts is supplied both below (underfire air) and above (overfire air) the grate. Mass bum combustors are erected at the site (as opposed to being prefabricated) and range in size from 50 to 1,000 tons/day of MSW throughput per unit. Mass bum combustors can be divided into mass bum/waterwall (MBAVW), mass bum/rotary waterwall (MB/RC), and mass bum/refractory wall (MB/REF) designs. The walls of a MBAVW combustor are constructed of metal tubes that contain pressurized water and recover radiant heat for production of steam and/or electricity. A typical MBAVW combustor is shown in Figure 4-9. With the MB/RC combustor, a rotary combustion chamber sits at a slight angle and rotates at about 10 revolutions per hour, causing the waste to advance and tumble as it bums. The combustion cylinder consists of alternating water tubes and perforated steel plates. Figure 4-10 illustrates a simplified process flow diagram for a MB/RC. MB/REF designs are older and typically do not include any heat recovery. One type of MB/REF combustor is shown in Figure 4-11. 46 4-45 TT 4-46 Figure 4-9. Typical Mass Bum Waterwall Combustor Superheater 4-47 Figure 4-10. Simplified Process Flow Diagram, Gas Cycle for a Mass Bum/Rotary Waterwall Combustor NO •*r o o c < T T o T O o O O w—m ■ i •— X X X X X ON cn r- NO o q co NO —• Nri —« *n v> © X 00 X r- to * © x co rs — — x m x m O x r~~ o o X co (N — X r~- co OJ o c c o U g Cl o 60 Z w L> C o Z CL CO UJ ul u. u >. re k> CL CO a. co W >3 re b* CL CO 1) c o Z UL U. i— OJ er Q >% re u. CL CO a. CO u ul g 3 ^ w. 5 C O 2 o co — Q ^ a i= CL CO CL CO w 9J c o z >% re ul u. t-i u Q >% re l. CL CO CL CO UU c U - UL b> v q a» •£ ^ >» re b. ■ CL CO o .2 >3 -c re b. CL CO CL CO UJ b> V >* re b. CL c/T o D i— 3 O CO c o c/3 UL 2 CL *3 s < b- •6 £ §J 1 b- re 2 -c co U o 3 ul T3 4 J > 'u 0/ Q i a> C/5 2 re £ rd w O ct E o ffl 3 X) E „ o S U C/5 C^ ct: £ E 3 z u u co o t co m O o t *n 3 o I *0 «n O o I *n 8 o I tn 4-53 TABLE 4-14. CONTINUED o re [i, Ofi c W O re 8 02 UJ U < < < U < < < u < < < u 1) co c re a l— n 2 § u — TO tt. £ §.S e tu u TO u. CO co E £ lE j- 4> M TO 1— 3J > < vt © X r**i O vi © X r-~ rs ro vO © o X r- m w-> o X r~~ x m fM Tt — — VI o x cn O VI o x p- ri x r~- m \o o x m rJ V I O X t"- m V o x m © — — v o X O O X r- cn x m c4 VI o x e'¬ en x m O VI o x — — rN u 2 > *_» - c U c u- 5 «- •£ = O o V) — I— • —1 C = c_ on UJ •> TO i— CL on a. on UJ c tt- iS % *- — o .2 on — >i u 2 Q IS* a. - on u >» TO a. on UJ >>» >% TO k. CL on a. on UJ — tt. E tt. fc £ & Q >% TO k. CL on o .a ^ o u Q £ Cl on w V a o Z tt. tt. k. > i_ re O a E o m s oo -2 to £ « o 2 u to CO a; u X UJ H re ■8 CO 3 — E o U TO o o TO vt 1» QC C O £ to CQ 3 E _ o 2 U CO CO TO TO 4J TO E o 1/5 CQ 3 co £ TO E 5 O S u i5 E 3 z u u on V *o — 60 § CC U. 2 S u 2 re '5: U. £ I = C/D C/D E uj u re U. .2 "c C/D O C/D — E 2 UJ c w 60 re k_ > < o Q c o U u k. 3 O on c _o CO co 1 UJ & E 3 z u u on < < < U ro © X r- m *p b x m rN W) © X m W1 © x <*1 O -re- — — «r> b x r- SJ c o Z re £ 2 re £ k. re o CC e s a I 1/3 "c CO £ « o 2 u m m o I U Q "T t o o x ON NO X m o NO — u. u. u. CL on UJ c u. u. u. u. k> a. on UJ a u. U. >> L. C k> 5J k. Q £ ka O on 3 o o ESP Mone ESP None V b Q k> V b Q Js k. o on .o a ESP re k. CL on >, re k> CL on Q OJ ■? re k~ CL on >c re k. O. on £* Q V 'o' _re 3 ■8 8 i m O i */■> < < < U m © X r- m © x o X m w> b x m o TT — _ •o o *x r- O X UJ m _ 3 = 1 2 u *8 «n m © wn NO • u C * £> >, _■§- 3 E / oT 60 ■JC O o kl E s. 60 n c o u o H •d 2 re k. D re k- w re o CO *- S 2 w c S .2 S S3 E UJ o re u o k. CL o re to 2 1 UJ ll - ll On on u. UJ u. 4-55 Fabric Filter. differ from one MWC unit to another, especially where the permit specifications for the accepted waste are different. Because of this variability, the factors shown in Table 4-14 must be used cautiously and may not be representative of other MWCs. Also, emission factor data may be available in databases developed by trade associations or other industry groups. 45 4.3.3 Source Location In 1997, there were 120 MWC plants operating in the United States with a total capacity of approximately 111,000 tons/day of MSW. Table 4-15 lists the geographical distribution of MWC units and statewide capacities. 49 4.4 Sewage Sludge Incinerators 4.4.1 Process Description The first step in the process of sewage sludge incineration is dewatering the sludge. Sludge is generally dewatered until it is about 15 to 30 percent solids, at which point it will bum without supplemental fuel. After dewatering, the sludge is sent to the incinerator for combustion. The two main types of sewage sludge incinerators (SSIs) currently in use are the multiple-hearth furnace (MHF) and the fluidized-bed combustor (FBC). Over 80 percent of the identified operating SSIs are MHFs and about 15 percent are FBCs. The remaining SSIs co-fire MSW with sludge. 50 Multiple-Hearth Furnaces A cross-sectional diagram of a typical MHF is shown in Figure 4-14. 50 The basic MHF is a vertically oriented cylinder. The outer shell is constructed of steel and lined with refractory material and surrounds a series of horizontal refractory hearths. A hollow cast iron rotating shaft runs through the center of the hearths. Cooling air is introduced into the shaft, which extends above the hearths. Attached to the central shaft are the rabble arms, which extend above the 4-56 TABLE 4-15. SUMMARY OF GEOGRAPHICAL DISTRIBUTION OF MWC FACILITIES (1997). State Number of MWC Facilities State MWC Capacity in tons/day Percentage of Total U.S. MWC Capacity Alabama 1 690 <1 Alaska 2 90 <1 Arkansas 1 40 <1 California 3 2,540 2 Connecticut 6 6,535 6 Florida 13 18,126 16 Georgia 1 500 <1 Hawaii 1 1,850 2 Illinois 1 1,200 1 Indiana 1 2,361 2 Iowa 3 282 <1 Maine 4 2,400 2 Maryland 3 4,410 4 Massachusetts 8 12,523 11 Michigan 4 2,525 5 Minnesota 15 7,930 7 Mississippi 1 150 <1 New Hampshire 2 700 <1 New Jersey 6 6,099 6 New- York 10 11,173 10 North Carolina 1 850 <1 Oklahoma 1 1,125 1 Oregon 1 550 <1 Pennsylvania 9 9,492 9 Tennessee 2 2,510 2 Texas 5 269 <1 4-57 TABLE 4-15. CONTINUED State Number of MWC Facilities State MWC Capacity in tons/day Percentage of Total U.S. MWC Capacity Utah 1 420' ' <1 Virginia 6 8,135 8 Washington 5 1,620 1 Wisconsin 3 520 <1 TOTAL 120 110,855 100 Source: Reference 49. 4-58 Furnace Exhaust to Afterburner 4 4 4 ft* Floating Damper ▲ Figure 4-14. Typical Multiple-Hearth Furnace Source: Reference 50. 4-59 ERG POM 4331 cdr hearths. Each rabble arm is equipped with a number of teeth approximately 6 inches in length and spaced about 10 inches apart. The teeth are shaped to rake the sludge in a spiral motion, alternating in direction from the outside in to the inside out between hearths. Burners, which provide auxiliary heat, are located in the sidewalls of the hearths.. In most MHFs, partially dewatered sludge is fed onto the perimeter of the top hearth. The rabble arms move the sludge through the incinerator by raking the sludge toward the center shaft, where it drops through holes located at the center of the hearth. In the next hearth, the sludge is raked in the opposite direction. This process is repeated in all of the subsequent hearths. The effect of the rabble motion is to break up solid material to allow better surface contact with heat and oxygen. A sludge depth of about 1 inch is maintained in each hearth at the design sludge flow rate. Under normal operating conditions, 50 to 100 percent excess air must be added to an MHF to ensure complete combustion of the sludge. Besides enhancing contact between the fuel and the oxygen in the furnace, these relatively high rates of excess air are necessary to compensate for normal variations in both the organic characteristics of the sludge feed and the rate at which it enters the incinerator. When an inadequate amount of excess air is available, only partial oxidation of the carbon will occur, with a resultant increase in emissions of CO, soot, and hydrocarbons. Too much excess air, on the other hand, can cause increased entrainment of particulate and unnecessarily high auxiliary fuel consumption. 50 Fluidized-Bed Combustors Figure 4-15 shows the cross-section diagram of an FBC. 50 FBCs consist of a vertically oriented outer shell constructed of steel and lined with refractory material. Tuyeres (nozzles designed to deliver blasts of air) are located at the base of the furnace within a refractory-lined grid. A bed of sand approximately 2.5 feet thick rests upon the grid. Two general configurations can be distinguished based on how the fluidizing air is injected into the furnace. In the hot 4-60 Exhaust and Ash Figure 4-15. Fluidized-Bed Combustor Source: Reference 50. 4-61 windbox design, the combustion air is first preheated by passing it through a heat exchanger, where heat is recovered from the hot flue gases. Alternatively, ambient air can be injected directly into the furnace from a cold windbox. Partially dewatered sludge is fed into the lower portion of the furnace. Air injected through the tuyeres at a pressure of 3 to 5 pounds per square inch gauge simultaneously fluidizes the bed of hot sand and the incoming sludge. Temperatures of 1,400 to 1,700°F are maintained in the bed. As the sludge bums, fine ash particles are carried out of the top of the furnace. Some sand is also removed in the air stream and must be replaced at regular intervals. Combustion of the sludge occurs in two zones. Within the sand bed itself (the first zone), evaporation of the water and pyrolysis of the organic materials occur nearly simultaneously as the temperature of the sludge is rapidly raised. In the freeboard area (the second zone), the remaining free carbon and combustible gases are burned. The second zone functions essentially as an afterburner. Fluidization achieves nearly ideal mixing between the sludge and the combustion air; the turbulence facilitates the transfer of heat from the hot sand to the sludge. An FBC improves the burning atmosphere, such that a limited amount of excess air is required for complete combustion of the sludge. Typically, FBCs can achieve complete combustion with 20 to 50 percent excess air, about half the excess air required by MHFs. As a consequence, FBCs generally have lower fuel requirements compared to MHFs. 50 Emission Control Techniques Certain conditions that affect the emission rates of arsenic in SSIs include: • Sludge metal content; • Operating bed temperature; • Flow patterns leading to solids drop-out ahead of APCD; and 4-62 • APCD control efficiency as a function of particle size. Clearly, the quantity of arsenic in the feed sludge is the basic scalar of emissions. Arsenic in sludge arises from several sources, including industrial discharges (especially plating wastes), corrosion of outtake plumbing materials, street runoff, and numerous lesser domestic and industrial activities. The arsenic content varies from day to day, reflecting a diversity of waste types. The temperature of the combustion environment influences the behavior of arsenic emissions because of the following sequence of events during incineration: 1. At elevated temperatures, many heavy metal compounds (including arsenic) vaporize. The higher the temperature, the larger the fraction of metals that is vaporized. 2. As temperatures drop, a fraction of the metals condenses. Condensation takes place in proportion to available surface area. 3. Collection of the metals condensed on the PM occurs while passing through the APCD system. 43 Arsenic emissions may be reduced by using PM control devices and reducing incinerator and APCD temperatures. The types of existing SSI PM controls include low-pressure-drop spray towers, wet cyclones, high-pressure-drop venturi scrubbers, and venturi/impingement tray scrubber combinations. A few ESPs and baghouses are employed, primarily where sludge is co-fired with MSW. The most widely used PM control device applied to an MHF is the impingement tray scrubber. Older units use the tray scrubber alone; combination venturi/impingement tray scrubbers are widely applied to newer MHFs and some FBCs. 50 4.4.2 Emission Factors Table 4-16 presents arsenic emission factors for SSIs. 50,51,52 The factors presented cover the two main incinerator types: MHFs and FBCs. Again, as the emission factor tables for the other types of incinerators (previously discussed) show, PM type control technologies offer the 4-63 TABLE 4-16. ARSENIC EMISSION EACTORS EOR SEWAGE SLUDGE INCINERATOR SOURCES oj o c o ,n m m m boob o o o X X X X X X X © © © © o o o rr © on on r- — © on — — — — tt rn U o> c o Z oj £ 2 oj 03 2 e OJ > oj c jo cj u _4> OO c v5 c V g 2 E 3 OJ JD OO >- C ~ a. c/3 UJ x 2 o 03 c oj > a. 03 UJ a> g u_ a X X 2 oj to M * 2 c oj a — b c b « 2 > E o> c _o "o U _4J "ob c c/5 X 2 c/3 c oj E OJ 00 c ■q. E J8 X 2 OJ C/3 c OJ E OJ O0 c *- •B.J8 E •§ b 2 OJ o c c/3 O OJ U a. 2 OO c c/3 £ x 2 OJ C/3 OJ OJ b. 3 O C/3 C _o bn bn UJ O re b. OJ c G 3 OJ OO X _3 03 ca OJ JLJ CL OJ OJ re | I -E U. OJ X 3 z u u 03 X o I 03 o t >n 03 03 O i 03 4-64 TABLE 4-16. CONTINUED V c 4> k. <2 4) Gt oo c -s o re in o* CO *S3 E 2 UJ cj TO U. U* ro o c O 2 £ ^ C C p •- co 4) e/3 OX) E 5 U Q£ 3 « .2 c CO o co — E £ w c t> T OX) re O oj > < o re U. o — sn «n •n CJ Q o o U 0) cj U* 3 O c/3 e _o V3 in E ua iS E 3 z u u C/3 T © x o TT . (N o I O "x O vO m fl ' T T ”T VI o o O © o X X X X X O 8 o 00 o V) o X) Os .£* i 'oT OX) c o 0> E & OX) .X > c o cj £ •a 2 re k. ox _c o c 2 V) re c o 8 . 2 '1 4) 8 . O Xi c • mm ■a 4) H 4) u! o re C/3 Cj X kx _re a. X 4) 're > o 4) kx 4) re Ox t. re C/3 lx © O s 2 CJ re CO In a> cj ta u— re •D CO O kx XX o £ o c CJ *C o cy 4) tu TO C/3 E £ l 11 a. ll U I 1 C/3 u. n 3 m u- 4-65 greatest efficiency for reducing arsenic emissions. Specifically, the FF and the venturi scrubber with impingement-type wet scrubber are the most effective control devices according to this set of data. Collection efficiencies for the control devices shown in Table 4-16 range from 80 to greater than 99 percent. 4.4.3 Source Location There are approximately 200 sewage sludge incineration plants operating in the United States. 53 Most SSIs are located in the eastern United States, although there are a significant number on the West Coast. New York has the largest number of facilities with 33; Pennsylvania and Michigan have the next largest number with 21 and 19 sites, respectively. 54 4.5 Medical Waste Incineration Medical waste incinerators (MWIs) bum both infectious (“red bag” and pathological) medical wastes and non-infectious general hospital wastes. The primary purposes of MWIs are to (1) render the waste innocuous, (2) reduce the volume and mass of the waste, and (3) provide waste-to-energy conversion. 4.5.1 Process Description Three main types of incinerators are used as MWIs: controlled-air or starved-air, excess-air, and rotary kiln. The majority (>95 percent) of incinerators are controlled-air units. A small percentage (<2 percent) are excess-air, and less than 1 percent were identified as rotary kiln. The rotary kiln units tend to be larger and typically are equipped with air pollution control devices. 55 Based on EPA’s 1995 inventory, twenty-six percent of all MWI’s are equipped with air pollution control devices. 56 4-66 Controlled-Air Incinerators Controlled-air incineration is the most widely used MWI technology, and now dominates the market for new systems at hospitals and similar medical facilities. This technology is also known as two-stage incineration or modular combustion. Figure 4-16 presents a schematic diagram of a typical controlled-air unit. 55 Combustion of waste in controlled-air incinerators occurs in two stages. In the first stage, waste is fed into the primary, or lower, combustion chamber, which is operated with less than the stoichiometric amount of air required for combustion. Combustion air enters the primary chamber from beneath the incinerator hearth (below the burning bed of waste). This air is called primary or underfire air. In the primary (starved-air) chamber, the low air-to-fuel ratio dries and facilitates volatilization of the waste and most of the residual carbon in the ash bums. At these conditions, combustion gas temperatures are relatively low (1,400 to 1,800°F). 55 In the second stage, excess air is added to the volatile gases formed in the primary chamber to complete combustion. Secondary chamber temperatures are higher than primary chamber temperatures-typically 1,800 to 2,000°F. Depending upon the heating value and moisture content of the waste, additional heat may be needed. Additional heat can be provided by auxiliary burners located at the entrance to the secondary (upper) chamber to maintain desired temperatures. 55 Waste feed capacities for controlled-air incinerators range from about 75 to 6,500 lb/hr (at an assumed fuel heating value of 8,500 Btu/lb). Waste feed and ash removal can be manual or automatic, depending on the unit size and options purchased. Throughput capacities for lower-heating-value wastes may be higher because feed capacities are limited by primary chamber heat release rates. Heat release rates for controlled-air incinerators typically range from about 15,000 to 25,000 Btu/hr-ft 3 . 55 4-67 I Figure 4-16. Controlled-Air Incinerator Source: Reference 55. 4-68 Excess-Air Incinerators Excess-air incinerators are typically small, modular units. They are also referred to as batch incinerators, multiple-chamber incinerators, or “retort” incinerators. Excess-air incinerators are typically a compact cube with a series of internal chambers and baffles. Although they can be operated continuously, they are usually operated in batch mode. 55 Figure 4-17 presents a schematic for an excess-air unit. 55 Typically, waste is manually fed into the combustion chamber. The charging door is then closed, and an afterburner is ignited to bring the secondary chamber to a target temperature (typically 1,600 to 1,800°F). When the target temperature is reached, the primary chamber burner ignites. The waste is dried, ignited, and combusted by heat provided by the primary chamber burner, as well as by radiant heat from the chamber walls. Moisture and volatile components in the waste are vaporized and pass (along with combustion gases) out of the primary chamber and through a flame port that connects the primary chamber to the secondary or mixing chamber. Secondary air is added through the flame port and is mixed with the volatile components in the secondary chamber. Burners are also installed in the secondary chamber to maintain adequate temperatures for combustion of volatile gases. Gases exiting the secondary chamber are directed to the incinerator stack or to an air pollution control device. After the chamber cools, ash is manually removed from the primary chamber floor and a new charge of waste can be added. 55 Incinerators designed to bum general hospital waste operate at excess air levels of up to 300 percent. If only pathological wastes are combusted, excess air levels near 100 percent are more common. The lower excess air helps maintain higher chamber temperature when burning high-moisture waste. Waste feed capacities for excess-air incinerators are usually 500 lb/hr or less. 55 Rotary Kiln Incinerators Rotary kiln incinerators are also designed with a primary chamber, where the waste is heated and volatilized, and a secondary chamber, where combustion of the volatile fraction is 4-69 Side View Figure 4-17. Excess-Air Incinerator Source: Reference 55. 4-70 ERG Lead 513.cdr completed. The primary chamber consists of a slightly inclined, rotating kiln in which waste materials migrate from the feed end to the ash discharge end. The waste throughput rate is controlled by adjusting the rate of kiln rotation and the angle of inclination. Combustion air enters the primary chamber through a port. An auxiliary burner generally is used to start combustion and maintain desired combustion temperatures. Figure 4-18 presents a schematic diagram of a typical rotary kiln incinerator. Volatiles and combustion gases pass from the primary chamber to the secondary chamber. The secondary chamber operates at excess air. Combustion of the volatiles is completed in the secondary chamber. Because of the turbulent motion of the waste in the primary chamber, solids burnout rates and particulate entrainment in the flue gas are higher for rotary kiln incinerators than for other incinerator designs. As a result, rotary kiln incinerators generally have add-on gas-cleaning devices. 55 Emission Control Techniques A majority of arsenic and other metal emissions are in the form of PM, and a minority is in vapor form. Particulate emissions of arsenic from the incineration of medical wastes are determined by three major factors: 1. Suspension of noncombuStible inorganic materials containing arsenic; 2. Incomplete combustion of combustible arsenic materials; and 3. Condensation of arsenic-based vaporous materials (these materials are mostly inorganic matter). Emissions of noncombustible materials result from the suspension or entrainment of ash by the combustion air added to the primary chamber of an incinerator. The more air that is added, the more likely that noncombustibles become entrained. Particulate emissions from incomplete combustion of combustible materials result from improper combustion control of the incinerator. Condensation of vaporous materials results from noncombustible substances that 4-71 Exhaust Gas to Stack or Air Pollution Control Device" 4-72 Source: Reference 55. volatilize at primary combustion chamber temperatures with subsequent cooling in the flue gas. These materials usually condense on the surface of other fine particles. 57 Typically, two strategies are used to minimize metals emissions: (1) combustion control in the primary chamber so as to reduce vaporization or entrainment of metals, and (2) capture of metals by use of an APCD. Both of these strategies are discussed below. The key APCD parameters used are specific to the device that is used. Combustion Control -Most MWIs are simple single-chamber units with an afterburner located in the stack. The ability of batch incinerators to control arsenic emissions is limited because only the temperature in the stack is usually monitored. Most new incinerators are starved-air units. The primary chamber is designed to operate at low' temperatures and low gas flow rates. This minimizes the amount of materials entrained or vaporized. To ensure that arsenic emissions are minimized, operators must maintain the primary chamber at the temperatures and gas flow rates for which it was designed. Usually the only parameter that system operators can directly control is feed rate. High feed rates can lead to high temperatures and high gas velocities. Thus, many operators carefully control the feed rate. The feed rate is reduced when primary temperatures increase. Keeping the temperature low enables the arsenic to condense on different sizes of particles, which are then easily trapped by PM control devices. APCD Control --When arsenic reaches the APCD, it is present in one of three forms. Non-volatile arsenic is present on large entrained particles. Arsenic that has vaporized and recondensed is usually enriched on fly-ash particles with diameters less than 1 micron. Other arsenic may be present as vapor. 57 The majority of arsenic emissions are in the first two forms and are controlled by PM control devices. Generally, particulate control is a surrogate for arsenic control in an incinerator/air pollution control system. 4 4-73 4.5.2 Emission Factors The available arsenic emission factors for MWIs are presented in Table 4-17. 55,58,59 Also, emission factor data may be available in databases developed by trade associations or other industry groups. 45 As with the other types of incinerators, waste composition is a critical factor in the amount of arsenic emitted. The arsenic emission factors were developed from tests at facilities burning red bag waste, pathological waste, and/or general hospital waste. Red bag waste is defined as any waste generated in the diagnosis or immunization of human beings or animals; pathological waste is defined as any human and animal remains, tissues, and cultures; and general hospital waste was defined as a mixture of red bag waste and municipal waste generated by the hospital. As with other combustion sources, the presented emission factors are highly dependent upon the composition of the waste. For example, the difference in the emission factors presented in Table 4-17 for both a high efficiency and medium efficiency wet scrubber with a fabric filter applied to an MWI is expected to be more a function of the arsenic content of the waste burned rather than scrubber efficiency. 4.5.3 Source Location There are an estimated 2,400 MWIs in the United States, located at such facilities as hospitals, health care facilities, and commercial waste disposal companies to dispose of hospital waste and medical/infectious waste. Most MWIs are located at hospitals. 4 Of the approximately 7,000 hospitals in the United States, fewer than half have MWIs. 60 4-74 TABLE 4-17. ARSENIC EMISSION FACTORS FOR MEDICAL WASTE INCINERATION SOURCES a c 4> h. 2 4> oc V) »n m w-> in »n «n m «n V~) m m m in m in m m m m >n m oo c *s O re "io 2 co •3 I-* £ ° u t> cz u. w CQ w a U UJ U U UJ u CQ a> oo g OC I— ro 2 £ c_> 2 re ^ u. £ c c .2 CO E w T © x m m co T © ”x C4 ni m • o X r- (N ro VTl O X r~ C_) > 1 i- y £ 5 2 £ £ w £ Cu CO UJ 'S o U V c u- o CO Q U- u. o o u u •£ — c 1 k. o CO £ Q u. uu o c I c a 8 t-4 CT3 u c 1 u. O CO £ Q a> c o Z c o Z u i— 3 O CO c _o Zn to E UJ I— re o re o "Sb o o oc o •E 2 S. 73 < u -a •5b 2 2 c o i: is cu U re u "5b o E re cu Commercial Incineration Pathological Kiln Commercial Incineration »n «n o o in in 8 8 Oi v> . •2 U £ o © o CT3 © cj GO s 2 § o — re © £ c c .2 •“ 'vi Vi E © .2 c v. O — tu c CJ *“■ 60 t CZ w §1 < u ov m oo m «n V) cj Q U OJ cj I— 3 o on c _o "33 00 E © u| U E co = Z © © © W © © © T © x VC 1 •a CJ S u. u. 3 • >> B _o c o c .Si u 1 OJ u c CJ k. CJ CJ c ^ CJ •g o o CJ "c 1 3 k. o CO © o— tu X E u CO CJ © V— © E £ co W CJ c JS U. O & a CJ CO £ £ Q c CZ u "E o o CJ © © "E o o CJ = -c o CO >l| u. Q © © 'E o u CJ re C cc o -2 .2 k- +* oo v 2 o i c o E •= 5 O g re U — a. m © i *n nJ © i m «n © >*• X >i .s- 3 E 3" GO c o cj E >_ S. 00 .X a> > c o cj H ■a a> re CJ _c o _c 4> vi re £ c o s. ■8 OJ I J3 I <— O X •a «j VI V) CJ k. a. x u CJ Wh re (A k. O tj <2 c o "35 00 © N CJ X) jre "re > re o c re re •a CJ E CJ (2 cj ‘C x re © II © © © re a OJ и. a. o 3 Vi © к. w U jL> W II a. CO © 4-76 4.6 Crematories 4.6.1 Process Description Crematory incinerators used for human cremation at funeral homes, mortuaries, cemetaries, and crematories are normally of an excess air design. They utilize secondary chamber (afterburner) and primary chamber (ignition) burners fueled by liquified petroleum (LP) gas or natural gas. Burner capacities are generally between 750,000 and 1,500,000 BTUs per hour per burner. Late model units have burner modulation capability to regulate chamber temperatures and conserve fuel. Incineration rates range from 100 to 250 pounds of remains per hour. Preheating and a minimum secondary chamber temperature, typically ranging from 1,400°F to 1,800°F, may be requirements. Although not suitable for this batch load type, of incinerator, the same requirements are occasionally applied to the primary chamber. The human remains and cremation container, generally made of cardboard or wood, are loaded onto the primary chamber hearth and the primary burner is ignited to begin the cremation process. The remains may be raked at the midpoint of the cremation to uncover unbumed material and speed the process. The average cremation takes from 1-1/2 to 3 hours, after which the incinerator is allowed to cool for at least 30 minutes so that the remains can be swept from the hearth . 61 4.6.2 Emission Factors Evaluation tests on two propane-fired crematories at a cemetery in California were conducted through a cooperative effort with the Sacramento Metropolitan Air Quality Management District to determine HAP emissions from a crematory. 62 The units were calibrated to operate at a maximum of 1.45 million Btu per hour. Emissions testing was performed over a 4-77 two-week period. Thirty-six bodies were cremated during the test period. The body, cardboard, and wood process rates for each test per crematory were reported. Sampling, recovery, and analysis for arsenic were performed in accordance with CARB Method 436. An emission factor developed from these data is presented in Table 4-18. 4.6.3 Source Locations In 1991, there were about 400,000 cremations in more than 1,000 crematories located throughout the United States. Table 4-19 lists the number of crematories located in each State and the estimated number of cremations performed in each State. J 4.7 Stationary Internal Combustion Sources 4.7.1 Emissions Air emissions from the flue gas stack are the only emissions from electricity generation, industrial turbines, and reciprocating engines. Internal combustion engines or turbines firing distillate or residual oil may emit trace metals carried over from the metals content of the fuel. If the fuel analysis is known, the metals content of the fuel should be used for flue gas emission factors, assuming all metals pass through the turbine. 64 The average fuel analysis result can be used to calculate emissions based on fuel usage or stack exhaust flow measurements. Potential emissions based on the trace element content of distillate oils have been calculated and compared with measured stack emissions. 65 In almost all cases, the potential emissions were higher than the measured emissions. An emission factor for distillate oil-fired turbines is presented in Table 4-20. 64 4-78 TABLE 4-18. ARSENIC EMISSION FACTOR FOR CREMATORIES 60 .5 TO as U o o TO D U* e o CO U 44 o 60 C »— TO X OS OS ro «_ P £ vd o 2 TO jP U- _Q c ~Z 1 wn b O c X ~co ro CO O' ”g3 04 UJ V Ui C 44 03 u. c « o b .2 2 X E ^ uj — 8 44 .E or 60 03 u 44 > < 44 44 > 44 Q 44 C o o u Z c o U 44 44 u 3 .X O o CO 2 c C/3 _o >> CO u CO o £ T3 u E 44 U u u 44 E o 3 • z 04 u O u cn C/3 ro *u a c5 E 60 c ‘ 5 . o. TO Ui £ JO O 04 II >* T3 2 •o C TO b. 44 c o c s. 04 VO 60 44 ’S 4-79 TABLE 4-19. 1991 U.S. CREMATORY LOCATIONS BY STATE State No. of Crematories No. of Cremations State No. of Crematories No. of Cremations Alabama 6 1,313 Montana 15 3,234 Alaska 6 860 Nebraska 7 1,710 Arizona 31 13,122 Nevada 12 6,343 Arkansas 13 2,435 New Hampshire 6 2,348 California 142 89,233 New Jersey 16 16,557 Colorado 27 9,537 New Mexico 10 3,140 Connecticut 10 5,528 New York 38 24,625 Delaware 4 1,062 North Carolina 27 6,884 District of Columbia 0 - North Dakota 1 - Florida 97 59,213 Ohio 42 16,109 Georgia 15 4,786 Oklahoma 10 2,120 Hawaii 8 3,937 Oregon 36 11,272 Idaho 13 2,637 Pennsylvania 46 16,867 Illinois 47 17,557 Rhode Island 5 2,446 Indiana 25 4,743 South Carolina 12 2,422 Iowa 14 3,042 South Dakota 3 - Kansas 10 2,029 Tennessee 9 2,451 Kentucky 6 1,548 Texas 39 13,795 Louisiana 5 2,466 Utah 6 1,210 Maine 4 3,469 Vermont 5 1,902 Maryland 18 6,300 Virginia 26 7,738 Massachusetts 13 10,611 Washington 49 18,466 Michigan 40 17,460 West Virginia 6 762 Minnesota 20 7,296 Wisconsin 28 7,293 Mississippi 4 693 Wyoming 3 - Missouri 23 6,105 Source: Reference 63. 4-80 TABLE 4-20. ARSENIC EMISSION FACTORS FOR INTERNAL COMBUSTION ENGINES OC c -S O C8 on Q£ CD •3 - e o UJ o «3 u. a> cm c c3 o£ 3 k. CQ 2 c % .2 1 u_ == 1 c ”2 o ‘55 X> C/3 E tu k- o CJ cs LL ca C 2 O CD VO *55 c .22 O <±> X E = “ E a> -C 8? rr &0 .o P3 — i— 03 > < 0) u > 03 a 03 c — o O u- Z r* c u 3 3 X 03 u. CJ 3 =3 h“ o ■a t>0 03 l— c o ICC 1 c/3 rzs C/3 o E 03 u J5 C/3 Q u 03 X E 3 © I z o u 8 u on o C4 s 03 O c 03 u. ,03 U—. 03 cc o> u i_ 3 O on •6 03 on 3 X) E o o 13 £ o— O 3 m c o E o X) ■a a> on on 43 o. a. x u 03 u. cc on u. O o c _o 03 03 E UJ 43 s J2 "ro > 4-81 4.7.2 Source Description Internal combustion sources for electricity generation and industrial application are grouped into two types: gas turbines and reciprocating engines.. Stationary gas turbines are applied in electric power generators, in gas pipeline pump and compressor drives, and various process industries. Gas turbines greater than 3 MW are used in electric generation for continuous, peaking, or standby power. The primary fuels used are natural gas and distillate (No. 2) fuel oil. 64 Reciprocating internal combustion engines may be classified as spark ignition and compression ignition. Spark ignition engines are fueled by volatile liquids such as gasoline, whereas compression ignition engines use liquid fuels of low volatility, such as kerosene and distillate oil (diesel fuel). 65 In compression ignition engines, combustion air is compression-heated in the cylinder and diesel fuel oil is then injected into this hot air. Ignition is spontaneous because the air is above the autoignition temperature of the fuel. Spark ignition engines initiate combustion with an electrical discharge. Usually, fuel is mixed with air in a carburetor (for gasoline) or at the intake valve (for natural gas), but fuel can also be injected directly into the cylinder. 66 The rated power of gasoline and diesel internal combustion engines covers a substantial range: up to 250 hp for gasoline engines and up to and greater than 600 hp for diesel engines. The primary domestic use of large stationary diesel engines (greater than 600 hp) is in oil and gas exploration and production. These engines supply mechanical power to operate drilling (rotary table), mud pumping, and hoisting equipment and may also operate pumps or auxiliary power generators. 67 Stationary natural gas-fired spark ignition engines of over 5,000 hp and natural gas-fired turbines of over 10,000 hp exist. 4-82 References for Section 4.0 1. National Research Council. Particulate Polycyclic Organic Matter. Washington, D.C.: Committee on Biologic Effects of Atmospheric Pollutants, Division of Medical Sciences, National Academy of Sciences, 1972. 2. National Research Council. Polycyclic Aromatic Hydrocarbons: Evaluation of Sources and Effects. Washington, D.C.: Committee on Pyrene and Selected Analogues, Board on Toxicology and Environmental Health Hazards, Commission on Life Sciences, National Academy Press, 1983. 3. Khan, R.M. Clean Energy from Waste and Coal. Developed from a symposium sponsored by the Division of Fuel Chemistry of the 202 nd National Meeting of the American Chemical Society. New York, New York: August 29-30, 1991. 4. U.S. EPA. Locating and Estimating Air Toxic Emissions from Medical Waste Incinerators. EPA-454/R-93-053. Research Triangle Park, North Carolina: 5. U.S. EPA. Correlation of Coal Properties with Environmental Control Technology Needs for Sulfur and Trace Elements. Contract No. 68-02-3171. 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Sources and Emissions of Polycyclic Organic Matter. EPA 450/5-83-010b. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, 1983. pp. 5-9 to 5-44. 10. Mead, R.C., G.W. Brooks, and B.K. Post. Summary of Trace Emissions from and Recommendations of Risk Assessment Methodologies for Coal and Oil Combustion Sources. EPA Contract No. 68-02-3889, Work Assignment 41. Research Triangle Park, 4-83 North Carolina: U.S. Environmental Protection Agency, Pollutant Assessment Branch, July 1986. 11. U.S. EPA. Fossil Fuel Fired Industrial Boilers - Background Information , Volume 1, Chapters 1 to 9. EPA-450/3-82-006a. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, March 1982. 12. AP-42, 5th ed., op. cit ., note 8. Section 1.6: Wood Waste Combustion in Boilers, 1995. 13. U.S. EPA. Population and Characteristics of Industrial/Commercial Boilers in the United States . EPA-600/7-79-178a. 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Washington, D.C.: U.S. Government Printing Office, July 1994. p. 861. 19. U.S. Code of Federal Regulations. Title 40, Protection of the Environment, Pan 279-Standards for the Management of Used Oil, Subpart C~Standards for Used Oil Generators, Section 279.23—On-Site Burning in Space Heaters. Washington, D.C.: U.S. Government Printing Office, July 1994. p. 863. 20. U.S. Code of Federal Regulations. Title 40, Protection of the Environment, Pan 279-Standards for the Management of Used Oil, Subpan G--Standards for Used Oil Burners who Bum Off-Specification Used Oil for Energy Recovery. Washington, D.C.: U.S. Government Printing Office, July 1994. pp. 877 to 880. 21. California Air Resources Board. Results of Source Testing at a Power Production Facility. Confidential Report No. ERC-83. November 8, 1991. 4-84 22. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 711. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 23. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 709. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. • 24. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 1054. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 25. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 706. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 26. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 714. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 27. California Air Resources Board. Determination of AB 2588 emissions from wood-fired boiler exhaust. Confidential Report No. ERC-63. February 10 - 13, 1992. 28. AP-42, 5th ed., op. cit., note 8. Section 1.2: Anthracite Coal Combustion, 1995. 29. AP-42, 5th ed., op. cit., note 8. Section 1.7: Lignite Combustion, 1995. 30. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 189. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 31. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 215. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 32. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 220. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 33. AP-42, 5th ed., op. cit., note 8. Section 1.3: Fuel Oil Combustion, 1995. 34. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 705. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 4-85 35. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 243. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 36. California Air Resources Board. Results of Source Testing at a Waste Converter Facility. Confidential Report No. ERC-118. September 26-28, 1990. 37. U.S. EPA. Locating and Estimating Air Emissions from Sources of Polycyclic Organic Matter (POM). EPA-450/4-84-007p. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1987. 38. Air & Waste Management Association. Air Pollution Engineering Manual , AJ. Buonicore and W. Davis, eds. New York, New York: Van Nostrand Reinhold, 1992. 39. Oppelt, E.T. Incineration of Hazardous Waste - A Critical Review. Journal of Air Pollution Control Association. 37(5):558-586, May 1987. 40. Vogel, G., et al (Mitre Corp). Composition of Hazardous Waste Streams Currently Incinerated. U.S. Environmental Protection Agency, April 1983. 41. U.S. EPA. Permit Writer's Guide to Test Bum Data - Hazardous Waste Incineration. EPA-625/6-86-012. Washington, D.C.: U.S. Environmental Protection Agency, Office of Research and Development, 1986. 42. Whitworth, W.E. and L.E. Waterland. Pilot-Scale Incineration of PCB-Contaminated Sediments from the Hot Spot of the New Bedford Harbor Superfund Site. Jefferson, Arkansas: Acurex Corporation, January 1992. 43. Niessen, W.R. and R.C. Porter. Methods for Estimating Trace Metal Emissions from Fluidized Bed Incinerators using Advanced Air Pollution Control Equipment. Air and Waste. 8:2-3, 1991. 44. California Air Resources Board. Results of Source Testing at a Chemical Waste Management Facility. Confidential Report No. ERC-108. May 25, 1990. 45. Rigo, H.G. Rigo & Associates, Inc. Berea, Ohio. Teleconference with Phil Marsosudiro. Eastern Research Group, Morrisville, North Carolina. March 30, 1998. 46. AP-42, 5th ed., op. cit., note 8. Section 2.1: Refuse Combustion, 1995. 47. Standards of Performance for New Stationary Sources, Municipal Waste Combustors, 54 FR 243 IV(f), December 20, 1989. 4-86 48. World Health Organization. Emissions of Heavy Metal and PAH Compounds from Municipal Solid Waste Incinerators. Control Technology and Health Effects. Copenhagen, Denmark: World Health Organization, Regional Office for Europe, 1988. 49. Integrated Waste Services Association. Municipal Waste Combustor Directory 1997-1998, Washington, D.C. October, 1997. 50. AP-42, 5th ed., op. cit., note 8. Section 2.2: Sewage Sludge Incineration, 1995. 51. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 234. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 52. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 101. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 53. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 101. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 54. U.S. EPA. Locating and Estimating Air Toxics Emissions from Sewage Sludge Incinerators. EPA-450/2-90-009. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, 1990. 55. AP-42, 5th ed., op. cit., note 8. Section 2.3: Medical Waste Incineration, 1995. 56. EPA-450/R-97-007. Hospital/Medical/Infectious Waste Incineration Emission Guidelines: Summary of the requirements for Section 1 ll(d)/129 State Plans. U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina. November, 1997. 57. Huffman, G.L. and C.C. Lee. Metal Behavior During Medical Waste Incineration. ACS Symposium Series Clean Energy from Waste and Coal, Chapter 15. August 1991. pp. 189-194. % 58. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 167. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 59. California Air Resources Board. Results of Source Testing at a Medical Waste Incinerator. Confidential Report No. ERC-114. August 1991. 60. U.S. Environmental Protection Agency. Fact Sheet —Air Emission Standards and Guidelines for HosptaUMedicaUInfectious Waste Incinerators. August 15, 1997. 4-87 61. Springer, J.M. (Executive Director, Cremation Association of North America). Personal correspondence to Dennis Beauregard (Emission Factor Inventory Group, U.S. Environmental Protection Agency). January 31, 1996. 62. California Air Resources Board. Results of Source Testing of a Propane-fired Incinerator at a Crematorium. Confidential Report No. ERC-39. October 29, 1992. 63. Cremation Association of North America. Cremation Statistics. Cremationist. Chicago, Illinois: Cremation Association of North America, 1994. 64. AP-42, 5th ed., op cit ., note 8. Section 3.1, Stationary Gas Turbines for Electricity Generation, 1995. 65. U.S. EPA. Emissions Assessment of Conventional Stationary Combustion Systems, Vol. D: Internal Combustion Sources. EPA-600/7-79-029c. Research Triangle Park, North Carolina: Industrial Environmental Research Laboratory, U.S. Environmental Protection Agency, February 1979. 66. AP-42, 5th ed., op cit., note 8. Section 3.3, Gasoline and Diesel Industrial Engines, 1995. 67 AP-42, 5th ed., op cit., note 8. Section 3.4, Large Stationary Diesel and All Stationary Dual Fuel Engines, 1995. 4-88 SECTION 5.0 EMISSIONS OF ARSENIC AND ARSENIC COMPOUNDS FROM THE METALLURGICAL INDUSTRY 5.1 Primary Lead Smelting Lead is recovered from a sulfide ore, primarily galena (lead sulfide [PbS]), which also contains small amounts of copper, iron, zinc, and other trace elements. Arsenic typically appears in the form of arsenopyrite (FeAsS) or arsenic sulfide (AS 2 S 3 ) in lead-bearing ore. A description of the process used to manufacture lead and a discussion of the emissions resulting from the various operations are presented below. A list of primary lead smelters currently in operation within the United States is given in Table 5-1. Primary lead smelters produced 449,800 tons of refined lead in 1990. 1 5.1.1 Process Description Figure 5-1 presents a typical process flow diagram for primary lead smelting. The recovery of lead from the lead ore consists of three main steps: sintering, reduction, and refining. 2 Sintering is carried out in a sintering machine, which is a continuous steel pallet conveyor belt. Each pallet consists of perforated grates, and beneath the grates are wind boxes, which are connected to fans to provide a draft through the moving sinter charge. Depending on the direction of the draft, the sinter machine is characterized as either an updraft or downdraft 5-1 TABLE 5-1. DOMESTIC PRIMARY LEAD SMELTERS AND REFINERIES Smelter Refinery 1990 Production tons ASARCO, East Helena, MT ASARCO, Omaha, NE a ' 72,500 ASARCO, Glover, MO Same site 123,200 Doe Run (formerly St. Joe), Same site 254,100 Herculaneum, MO - Source: Reference 1. a Scheduled to be closed. machine. Except for the draft direction, all machines are similar in design, construction, and operation. Capacities range from 1,000 to 2,500 tons per day. Lead concentrates account for 30 to 35 percent of the input material for the sintering process. The balance of the charge consists of fluxes such as limestone and large amounts of recycled sinter or smelter residues. 3 The blast furnace reduces the lead oxide produced in the sintering machine to elemental lead and removes undesirable impurities as a slag. Reduction reactions to elemental lead occur around 2,900°F. The resulting metal, called bullion, assays 94 to 98 percent lead. The furnace is a rectangular, water-cooled steel shell or shaft atop a refractory lined crucible or hearth. Both sides are equipped with tuyeres through which pressurized combustion or blast air is introduced. Furnace capacities range from 500 to 1,000 tons per day. The charge to the furnace includes sinter, coke, slags from drossing and refining processes, silica, limestone, and baghouse dust. About 80 percent of the charge consists of sinter that may contain from 28 to 50 percent lead. Blast air is introduced through the side-mounted tuyeres resulting in partial combustion of coke and formation of carbon monoxide and providing the heat required to reduce lead oxide to lead bullion. Most of the impurities react with the silica and limestone and form a slag. The slag is skimmed continuously from the furnace and is treated either at the smelter or is shipped elsewhere to recover the metal content. Slags that are high in zinc are generally treated at the smelter in a zinc forming furnace to recover zinc oxide. 3 5-2 CN V o c 80 percent) can be accounted for in the solid products leaving a facility. 4 Arsenic can potentially be emitted from each unit operation within a primary lead smelting facility. Arsenic removal from the lead-bearing portion of the charge material includes volatilization, slagging, and an association with the matte and speiss phases (mixture of impure metallic arsenides) that are ultimately shipped to copper smelters. Typically, arsenic will be emitted as PM. If any particle size partitioning occurs, it is generally found that arsenic is most likely to be associated with the finer particles. 4 In addition, for processes where the operating temperature is near the boiling point of arsenic, arsenic fumes may be emitted. For example, arsenic can be volatilized as arsenic trioxide from sinter plants, blast furnaces, dross reverberatory furnaces, zinc fuming furnaces, and reverberatory softening furnaces (lead refining). 4 One study from a Missouri lead smelter determined that approximately 12.9 percent of the arsenic entering a smelter was unaccounted for in the solid waste and product streams. The study concluded that this figure represented the approximate amount that was emitted to the atmosphere. 4 Table 5-2 presents an arsenic emission factor that may be used for estimating arsenic emissions from an entire primary lead smelting operation 4 The reader is cautioned that this emission factor represents a rough estimate only and the quality of the factor is uncertain. 5.2 Secondary Lead Smelting 5.2.1 Process Description The secondary lead smelting industry produces elemental lead and lead alloys by reclaiming lead, mainly from scrap automobile batteries. Blast, reverberatory, rotary, and electric furnaces are used for smelting scrap lead and producing secondary lead. Smelting is the 5-5 TABLE 5-2. ARSENIC EMISSION FACTOR FOR PRIMARY LEAD SMELTING FACILITIES £>4 c S' .2 3 c/5 QC C/5 E U < U CD ’> O Q c U o u L_ 3 o 00 c o 'd5 C/5 E UJ u U 00 X o oo uri ts I O X o oo » x> jx a. *3 £ / o c c o w "ab c o E ka o Cl oo -x C o o o H •d 4> u 3 *o O -o re 05 e o o c. -o o E Q£ c/a D 3 £ J=L u. re 2 S o 2 U. £ c c o ■- 4) on OX) E 5 uj a: oo © X .3 e co O CO — E £ w c 4> re O 4> ££ > r < U - TT © — fM o o o X aa X 1/0 X X CM 4) Q c c U Ua u- •o ka OJ OJ 4) w X c PM in Ua 3 O ha £ U X Ua C o u. o *1— p* w CJ X) cz c cd U. < D u. 4) £ fc | — X> B. 2 oo ha X) re U. CO U C o Ua 4) CJ E 2 w •2 u. 4) 4) CJ ha 3 O C/0 c _o CO CO E cu 2 £ u- OX) OX) c o 4> 4> CJ 5 3 w • 2 c c 4) 3 *5. Ca re c3 Ua £ ■o 5 re 3 ha 3 u. GJ CJ cn c o ha 0/ p c t o *35 re SC •T3 C E 3 U. H •o § 4) > 4) Oi 4) CJ re e re 4) CJ re c o£ ka 3 ha 3 £ re 4> ox) re co 4) oo c •o e f/i GJ u 3 t. 3 OX) c u. X> ha 4) U CO > ha re CJ C3 r? u. Ua w c "E "o r- c co re 3 i CO 3 i r*“> 3 i CO co O 3 m 3 i m 5-20 the charging operationanclude fine particulates and fumes, originating from recycled flue dusts which can contain significant amounts of arsenic. The slag and metal tapping operations incorporate high temperatures and therefore generate a considerable amount of fumes. Those fumes that are not captured and controlled represent process fugitive emissions. Fugitive nonprocess arsenic emissions will be affected by the arsenic content of the various fine materials being stored at the smelter including the non-agglomerated flue dusts and the dried battery mud. The flue dust storage pile in the charge preparation area is the primary source of nonprocess fugitive arsenic emissions at a secondary lead smelting facility. 4 In » addition, battery breaking yards, battery storage areas, slag storage areas, and smelter access roads have all been identified as potential sources of nonprocess fugitive arsenic emissions. Meteorological factors (in particular the amount of wind and rain) and the amount of activity around the plant site can influence the total amount of arsenic from this source. 4 5.2.4 Source Locations In 1990, primary and secondary smelters in the United States produced 1,380,000 tons of lead. Secondary lead smelters produced 946,000 tons or about 69 percent of the total refined lead produced in 1990. 5 Table 5-4 lists U.S. secondary lead smelters according to their annual lead production capacity. 5 5.3 Primary Copper Production 5.3.1 Source Description Seven primary copper smelters were operating in the United States in 1995 and one more was closed for modifications. The combined production capacity in 1995 for the seven plants in operation was 1,728,043 tons. 10 5-21 TABLE 5-4. U.S. SECONDARY LEAD SMELTERS GROUPED ACCORDING TO ANNUAL LEAD PRODUCTION CAPACITY Smelter Location Small-Capacitv Group:* Delatte Metals b Ponchatoula, LA General Smelting and Refining Company College Grove, TN Master Metals, Inc. b Cleveland, OH Metals Control of Kansas b Hillsboro, KS Metals Control of Oklahoma b Muskogee, OK Medium-CaDacitv Qpoup: c * Doe Run Company Boss, MO East Penn Manufacturing Company Lyon Station, PA Exide Corporation Muncie, IN Reading, PA GNB, Inc. Columbus, GA Frisco, TX Gulf Coast Recycling, Inc. Tampa, FL Refined Metals Corporation 6 Beech Grove, IN Memphis, TN RSR Corporation City of Industry, CA Middletown, NY Schuylkill Metals Corporation Forest City, MO Texas Resources, Inc. b Terrell, TX Large-Capacitv Group: d Gopher Smelting and Refining, Inc. Eagan, MN GNB, Inc. Vernon, CA RSR Corporation Indianapolis, IN Sanders Lead Company Troy, AL Schuylkill Metals Corporation Baton Rouge, LA Source: Reference 5. a Less than 22,000 tons. b These facilities were not operating as of January 1995. c 22,000 to 82,000 tons. d Greater than 82,000 tons. 5-22 5.3.2 Process Description The pyrometallurgical process used to extract copper from sulfide ore concentrates (“concentrates”) is based upon copper’s strong affinity for sulfur and its weak affinity for oxygen as compared to that of iron and other base metals in the ore. The purpose of smelting is to separate the copper from the iron, sulfur, and commercially worthless mineral materials generally referred to as “gangue.” All of the primary copper smelters currently produce anode copper from sulfur-bearing ores with the same basic processes: 10 • matte smelting (i.e., smelting of concentrates to produce matte); • matte converting (to produce blister copper); and • refining of blister copper in an anode furnace (to produce anodes). Copper concentrates are received by the smelter that typically contain 24 to 30 percent copper, 30 percent sulfur, 25 percent iron, and 10 to 20 percent oxides of silicon, calcium, aluminum, magnesium, and zinc (usually present as sulfide). (Copper-bearing ores typically contain 0.5 to 1 percent copper by weight. A froth-flotation process is utilized to produce the “concentrate.” This froth-flotation process may or may not be performed at the smelter site.) Concentrates also contain impurities, such as lead, arsenic, antimony, cadmium, chromium, cobalt, manganese, mercury, nickel, and selenium. These impurities are typically found in combined concentrations of less than one percent. The smelter may also receive copper scrap (for direct input into the converters), or may receive other non-concentrate inputs, such as precipitates, or copper “speiss.” Incoming concentrates are typically dried before charging into a smelting furnace or reactor. Several types of smelting fumaces/reactors are currently utilized in the United States, including flash furnaces, CONTOP reactors, and IsaSmelt reactors. Figure 5-7 illustrates basic smelting operations. 10 5-23 Ore Concentrates with Silica Fluxes Slow Cool, Milling Flotation Anode Copper (>98.5% Cu) 1 To Electrolytic Refinery Figure 5-7. Typical Primary Copper Smelter Flow Sheet Source: References 10 and 11. 5-24 The smelting fumace/reactor produces molten copper matte, typically containing 55-75 percent copper, which is tapped from the furnace, and transferred by ladles to converters. The smelting fumace/reactors also produces slag, containing relatively low amounts of copper (typically less than two percent). This slag may be discarded directly, if less than 1 percent copper, or may be transferred to an electric slag cleaning vessel (for further copper removal), or may be cooled and reconcentrated (again, in an attempt for further copper removal). In the converters, further sulfur is removed from the matte, and in addition, iron is oxidized and separated by skimming. The output from the converters is “blister” copper, generally containing greater than 98 percent copper. Figure 5-8 illustrates a typical converter. 12 Molten blister copper is poured from the converter, and transferred by ladles to anode furnaces, where further refining by removal of oxygen and other impurities takes place. The resulting “anode” copper is generally greater than 98.5 percent pure. It is cast into anodes for use in the final electrolytic refining step. Further refining of “anode” copper into “cathode” copper (greater than 99.9 percent purity) is performed by electrolytic means in a “tank house.” Production of cathode copper may or may not take place at the smelter site. 5.3.3 Emissions PM and SCk are the principal air contaminants emitted from primary copper smelters. Actual emissions from a particular smelter will depend upon the smelting configuration (type and mix of equipment used), control devices applied, and the operating and maintenance practices employed. Typically, arsenic will be emitted as PM. In addition, actual arsenic emissions will vary depending on the quantity of arsenic introduced to the smelter as copper-bearing feed materials. Table 5-5 presents arsenic emission factors available from one EPA report. 13 In 5-25 Figure 5-8. Copper Converter Source: Reference 12. 5-26 TABLE 5-5. ARSENIC EMISSION FACTORS FOR PRIMAKY COPPER SMELTING FACILITIES -rr - o 3 re U. M G-S O re '3 Q£ co 3 3 D D D D D Z> D D D 4> 00 § 1 o fS < o < V u ’> o c c U 0/ w V CJ CJ CJ CJ r* c c c G c c c o o o O o o Z Z Z Z Z Z Z a. C/5 UJ CL 00 u CJ m 3 O J= oo ra CQ £ 2 c/5 *Im S G cj o k. 3 O 00 _o 'c/5 co E UJ cj.— 00 ra O 0£ ra cj ■o CJ N ‘•5 w .3 o C/3 c CJ > ’cb 3 ra o 3 E E U- 3 C>0 1 u U- *s CJ UJ CJ ra C k- CJ E 3 « > 3 u. i !2 u. u. #■ 'ob 3 o !- U. o W OJ cj <£ ra . 2 » .i c- 3 2 «g Si* s B £ ^ a > -o <*- CJ CJ < Oi CQ c o U ra co k- c JS.2 U- C/3 CO v E 06 UQ cj 00 ra O a: ■o o CQ "O C - a zjj 3 2 CJ co > 2 CJ O 06 06 cj <06 ra ka 4J "3 E oo o k» ra cj C cj > c o U ra k- cj < u — > 5/3 u 2 oc 2 CO C ,2 ra k> 3 oo c: c o CJ "ra cj t; CJ > c o U CO C O "co CO cj uj CO re O 06 •a oo 3 U. 00 G to « O 06 cj > OO 3 u. a> u ra E 3 U- & o ra co k. r- £.2 t— C/3 QJ CO v E 06 tt •o cj . N u< n L/ u 8 8 8 8 8 8 8 8 8 8 8 8 8 on i i m i m i CO i CO CO CO CO rn CO CO rn m c o o O O O O O O i O 1 o 1 o 1 o 1 1 m 1 m t CO CO cn CO CO CO CO CO CO CO CO n 5-27 Emission factors are expressed in lb of pollutant emitted per ton of concentrated ore processed. To convert to kg per metric ton (kg/tonne), multiply by 0.5. addition to process emissions, significant quantities of fugitive emissions are also generated during material handling operations and furnace charging and.tapping. As a general observation, particulate emissions from primary smelting operations are predominantly metallic fumes in the submicrometer range. A variety of particulate contaminants are typically emitted during the roasting process. They vary in composition depending on the particular ore being roasted. Copper and iron oxides are the primary constituents, but other oxides such as those of arsenic, antimony, mercury, lead, cadmium, and zinc may also be present with metallic sulfates and sulfuric acid. Combustion products from fuel burning also contribute to the emissions from roasters and reverberatory smelting furnaces. Fugitive particulates emitted from primary copper smelting consist primarily of metallic oxides and dust. Major sources of fugitive emissions are shown in Figure 5-9. 10 Principal sources include ore concentrate unloading and handling, roaster calcine transfer operations, furnace tapping operations, and converter charging and skimming operations. 5.3.4 Emission Control Techniques Control devices for particulate emissions from roasting, smelting, and converting operations include mechanical collectors (cyclones and settling flues), hot and cold ESPs, baghouses, and scrubbers. ESPs, usually preceded by mechanical collectors and operated at elevated temperatures, are by far the most common control devices. The control techniques applied vary depending on smelter configuration, process equipment mix, emissions characteristics, and feasibility for S0 2 control. Off-gases from smelting equipment that produce relatively high concentrations of S0 2 (greater than 4 percent; includes fluidized bed roasters, non-reverberatory smelting furnaces, and converters) are generally treated in single- or double-contact sulfuric acid plants for S0 2 removal. 5-28 d OJ u c u DC CJ c wo w-> VO <1> o c o ca __ o; x X X oo TT tT O c r* vn CJ _o W) fS C3 u_ -O so NO «n c c o o o o • »— C/3 X X X C/3 T m r- E UJ r-~ SO rS u. c NO o CJ C3 -C sO WO o u. o n X — zz X sc X c Psl CJ CJ 3 C/3 a u. 3 >> “ CJ c r> O .3 u c • — CO SJ 3 ca CD .£■ o 3 3C U CJ 3 > OJ • CJ u< CO 3 c O C/) c a o C/3 00 C/3 c E c U) UJ 3 cc Lm £ ON o E — 3 z 8 u b u b 00 m U 60 a o E 8. 00 C 41 > C o u b T3 QJ to to <-> O to C « cj E 3 C 'E J5 P3 u O C O •o CJ E 2 + 7C - 2FeSi + 7 CO Smelting in an electric arc furnace is established by converting electrical energy to heat. As an alternating current is applied to the electrodes, current is forced to flow through the charge between the electrode tips. This produces a reaction zone at temperatures up to 3,632°F. The tip 5-39 TABLE 5-8. FERROALLOY PROCESSES AND RESPECTIVE PRODUCT GROUPS Process Product Submerged arc fumace a Silvery iron (15-22% Si) Ferrosilicon (50% Si) Ferrosilicon (65-75% Si) Silicon metal Silicon/manganese/zirconium (SMZ) High carbon (HC) ferromanganese Siliconmanganese HC ferrochrome Ferrochrome/silicon FeSi (90% Si) Exothermic b Silicon reduction Low carbon (LC) ferrochrome LC ferromanganese Medium carbon (MC) ferromanganese Aluminum reduction Chromium metal Ferrotitanium Ferrocolumbium Ferovanadium Mixed alurrunothermal/silicothermal Ferromolybdenum Ferrotungsten Electrolytic 0 j Chromium metal Manganese metal Vacuum fumace d LC ferrochrome Induction furnace 0 Ferrotitanium Source: Reference 17. Process by which metal is smelted in a refractory-lined cup-shaped steel shell by submerged graphite electrodes. b Process by which molten charge material is reduced, in exothermic reaction, by addition of silicon, aluminum, or a combination of the two. Process by which simple ions of a metal, usually chromium or manganese in an electrolyte, are plated on cathodes by direct low-voltage current. d Process by which carbon is removed from solid-state high-carbon ferrochrome within vacuum furnaces maintained at temperatures near melting point of alloy. Process that converts electrical energy into heat, without electrodes, to melt metal charges in a cup or drum- shaped vessel r 5-40 C/D c/d ll aj c OB — re Ua > < (U CJ ’> i) a c c U o i— 3 O OO c _o co CO £ u u u 00 D D D < < < Z Z Z rs O ro O O X O 05 X o m c-j — — aj aj 3 3 O C Z z £ xi E $ 3 a aj cj re 3 CJ i— < o cj a/ 4J CJ re 3 L. 3 U. u < < CJ CJ CJ £ E 3 U- o aj U U U1 o I r~ (N o o c aj L. £ OJ CC v CJ ba 3 o 00 m Tt o ►> JD >* •a i CB c aj > C o CJ aj £ E a X) T3 aj E 3 co s o CJ OB b* aj c aj 8 . •T3 aj E aj s re .a> 5-46 often used to dry raw materials. These dryers can generate substantial quantities of particulate emissions. The majority of open electric arc furnaces are controlled with fabric filters, although to a much lesser extent, scrubbers and electrostatic precipitators are also used. For covered furnaces, two emission capture systems are necessary. While a primary capture system is used to withdraw gases from under the furnace cover, a secondary system captures fumes released around the electrode seals during tapping. Scrubbers are the most common control device used to control exhaust gases from sealed furnaces. Afterburners are always used to bum off CO after control devices for covered furnaces. Tapping operations also generate fumes. Some plants capture these emissions with a main canopy hood, while others use separate tapping hoods ducted to either the furnace emissions control device or a separate control device. Dust from pretreatment activities may be controlled by dust collection equipment such as scrubbers, cyclones, or fabric filters. 5.6 Iron and Steel Foundries 5.6.1 Process Description Iron and steel foundries produce gray, white, ductile, or malleable iron and steel castings. Both cast irons and steels are solid solutions of iron, carbon, and various alloying materials. Although there are many types of iron and steel, groups can be distinguished by their carbon composition. Cast iron typically contains 1 percent carbon or greater; cast steel usually contains less than 1 percent carbon. 18,19 5-47 Iron castings are used in many types of equipment, including motor vehicles, farm machinery, construction machinery, petroleum industry equipment, electrical motors, and iron and steel industry equipment. Steel castings are used in railroad equipment, construction machinery, motor vehicles, aircraft, agricultural equipment, ore refining machinery, and chemical manufacturing equipment. 18 Steel castings are classified on the basis of their composition and heat treatment, which is determined by their end use. Classifications include carbon, low-alloy, heat-resistant, corrosion-resistant, and wear-resistant. The following four basic operations are performed in all iron and steel foundries: • Storage and handling of raw materials; • Preparation of the molds to shape the molten metal; • Melting of the raw materials; and • Pouring of hot molten metal into molds. Other processes present in most foundries include: • Sand preparation and handling; • Mold cooling and shakeout; • Casting cleaning, heat treating, and finishing; • Coremaking; • Pattern making; and • Sand reclamation. A generic process flow diagram for iron and steel foundries is shown in Figure 5-14. 18 Figure 5-15 depicts the emission points in a typical iron foundry. 17 5-48 Tt t tn w i_ 3 60 U- 5-49 Source: References 18 and 20. Fugitive Particulates Figure 5-15. Emission Points in a Typical Iron and Steel Foundry Source: References 17 and 20. 5-50 Metal Melting Process In a typical foundry operation, charges to the melting unit are sorted by size and density and cleaned (as required) prior to being put into the melter. Charges consist of scrap metal, % * ingot, carbon (coke), and flux. Prepared charge materials are weighed and transferred into the melting furnace by crane buckets, skip hoists, or belt feeders. The charge in an electric furnace or cupola is heated until it reaches a certain temperature and the desired product chemistry of the melt has been attained. After the desired product is obtained, the molten metal is either poured out of the furnace into various-size transfer ladles and then into the molds or it is transferred to holding furnaces for later use. The metal melting process in iron and steel foundries is accomplished in cupolas and in electric arc furnaces (EAFs) and electric induction furnaces (EIFs). Cupolas are used to melt iron for casting and are charged with alternate layers of coke, metallics, and fluxes. Combustion air is introduced into the cupola through tuyeres located at the base. The heat produced by the burning coke melts the iron, which flows down and is tapped from the bottom of the cupola. Fluxes combine with impurities in the charge and form slag, which is removed through tap holes located above the level of the metal tap hole. Cupola capacities range primarily from 1 to 30 tons per hour, with a few large units capable of producing close to 100 tons per hour. Larger furnaces are operated continuously for several days with inspections and cleanings between operating cvcles. 21 j Iron and steel castings are produced in a foundry by pouring molten metal into molds made of sand, metal, or ceramic material. Steel foundries rely on EAFs or induction furnaces for melting purposes. In all types of foundries, when the metal has solidified, the molds are destroyed and the castings are removed on a shakeout unit. Abrasive (shotblasting) cleaning, grinding, and heat treating are performed as necessary. The castings are then inspected and shipped to plants of other industries for machining and assembly into a final product. 18 5-51 Mold and Core Production In addition to melting, the casting or mold pouring and cooling operations in iron and steel foundries are suspected to be a source of arsenic emissions. Also, mold preparation and casting shakeout (removal from the mold) activities are also suspect as arsenic emission sources, although test data are not available to quantify actual arsenic emissions. 5.6.2 Emission Control Techniques Control technologies commonly used to control arsenic emissions from iron and steel foundry metal melting operations include baghouses and wet scrubbers. Fugitive emissions from molding, casting, and shakeout are generally controlled with local hooding or building ventilation systems that are ducted to a control device (predominantly baghouses). 21 5.6.3 Emission Factors Arsenic emission factors were available for an arc furnace in a steel mill and cupola within an iron foundry. These emission factors are presented in Table 5-10. 22,23 5.6.4 Source Locations There were 756 iron and steel foundries in the United States in 1992 based on a survey conducted by the EPA in support of the iron and steel foundry Maximum Achievable Control Technology (MACT) standard development. 24 In general, foundries are located in areas of heavy industry and manufacturing, especially areas where iron and steel are produced (e.g., the Great Lakes States). 5-52 TABLE 5-10. ARSENIC EMISSION FACTORS FOR IRON AND STEEL FOUNDRIES o c oj l-a .0J < 4 — 0J Oi u re U, c o oa c re co a£ LU OJ 00 o c U 2 £ £ I S C/3 go E UJ E tu oj a ’> aj Q c o U oj oj t—i 3 O on c _o co E tu OJ £> E 3 z u u on CJ m cs m cs VO © o X X OS r- TT f-M r-~ 1 1 so to SO 1 b © X x t- r~ m sd TT V •o > .£• 3 E 'S' 00 c o 3J E ha OJ CL oo .x oj > c o OJ o E- •o OJ o 3 T3 O 8 . CO 03 OJ C O OJ a. •a OJ E OJ o CL Oka O JO •o OJ co CO OJ la CL X OJ OJ La 03 CO La O U .re c o OJ -X O O cl 03 La OJ CO OJ OJ c o CL re La OJ CO C O oo ‘E. OJ X3 _3 _c CO "re La OJ re E £ re © OJ Ca c o O co re OJ re oo 2 c OJ OJ 03 o c o OJ 3 8 Urn Cl Ua 2 c o c OJ 3 E CO OJ 2 > o Cl oj CO G co O cfl m u - 1 t§ i CU .c CL s « jo oi 3 _re ’re > re o c re -a c/3 § OJ E r i 3 * 5-53 References For Section 5.0 1. Woodbury, W.D. Annual Report 1990, Lead. Washington, D.C.: Bureau of Mines, U.S. Department of the Interior, U.S. Government Printing Office, April 1992. 2. U.S. EPA. Compilation of Air Pollutant Emission Factors , 5th ed. (AP-42), Vol. I: Stationary Point and Area Sources, Section 12.6: Primary Lead Smelting. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, 1995. 3. U.S. EPA. Control Techniques for Lead Air Emissions, Unpublished Draft. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Emission Standards Division, 1990. 4. U.S. EPA. Preliminary Study of Sources of Inorganic Arsenic. EPA-450/5-82-005. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, August 1982. 5. U.S. EPA. Secondary Lead Smelting Background Information Document for Proposed Standards, V olume 1. EPA-450/R-94-024a. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, June 1994. pp. 2-1 to 2-36. 6. Hall, R.M. and J.L. Gittleman. Control Technology for Metal Reclamation Industries at Sanders Lead Company Inc. CT-202-1 la. Cincinnati, Ohio: U.S. Department of Health and Human Services, Engineering Control Technology Branch, Division of Physical Sciences and Engineering, NIOSH, July 1993. pp. 1-8. 7. Rives, G.D. and A.J. Miles, Radian Corporation. “Control of Arsenic Emissions from the Secondary Lead Smelting Industry - Technical Document.” Prepared for U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, 1985. 8. Pacific Environmental Services, Inc. Draft Final Test Report, East Penn Manufacturing Company, Secondary Lead Smelter , Volume I, Report and Appendices A and B. Research Triangle Park, North Carolina: Pacific Environmental Services, Inc, March 15, 1994. 9. U.S. EPA. Assessment of the Controllability of Condensible Emissions. EPA-600/8-90-075. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Air and Energy Engineering Research Laboratory, October 1990. 10. U.S. EPA. Primary Copper Smelters. National Emission Standards for Hazardous Air Pollutants (NESHAP), Final Summary Report. ESD Project No. 91/61. Research 5-54 Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Emission Standards Division, July 1995. 11. Parameswaran, K. Asarcolnc. New York, NY. Fax to Phil Marsosudiro. Eastern Research Group. November 26, 1997 12. U.S. EPA. Control Techniques for Lead Air Emissions, Vol. II, Chapter 4 to Appendix B. EPA-450/2-77-012. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Emission Standards Division, 1977. 13. U.S. EPA. Inorganic Arsenic Emissions from High-Arsenic Primary Copper Smelters Background Information for Proposed Standards. EPA-450/3-83-009a. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, April 1983. 14. AP-42, 5th ed., op. cit., note 2. Section 12.8: Secondary Aluminum Operations, 1995. pp. 12.8-1 to 12.8-7. 15. California Air Resources Board. Source Emissions Testing of an Aluminum Shredding and Delacquering System, March and April 1992. Confidential Report No. ERC-8. . 16. California Air Resources Board. Emissions Measurements of a Delacquering Unit for AB2588 Toxics , September 7, 1991. Confidential Report No. ERC-32. 17. AP-42, 5th ed., op. cit., note 2. Section 12.5: Iron and Steel Production, 1995. 18. AP-42, 5th ed., op. cit., note 2. Section 12.5: Iron and Steel Production, 1995. 19. Monroe, R. W. Steel Founders’ Society of America. Des Plaines, flinois. Letter to Dennis Beauregard. U.S. EPA, Research Triangle Park, North Carolina. September 30, 1997. 20. Maysilles, J. U.S. Environmental Protection Agency. Memorandum to Dennis Beauregard. U.S. EPA, Research Triangle Park, North Carolina. September 1996 21. U.S. EPA. Emission Factors for Iron Foundries - Criteria and Toxic Pollutants. EPA 600/2-90-044. Cincinnati, Ohio: Control Technology Center, Office of Research and Development, 1990. 22. California Air Resources Board. Source Emissions Testing from an ARC Furnace Baghouse. Confidential Report No. ERC-60. June 25, 1990. 5-55 23. California Air Resources Board. Source Emissions Testing of a Baghouse to Quantify Foundry Emissions. Confidential Report No. ERC-59. December 1990. 24. California Air Resources Board. Source Emissions Testing of a Baghouse to Quantify Foundry Emissions. Confidential Report No. ERC-59. December 1990. 5-56 SECTION 6.0 EMISSIONS OF ARSENIC AND ARSENIC COMPOUNDS FROM THE PULP AND PAPER INDUSTRY Chemical wood pulping involves the extraction of cellulose from wood by dissolving the lignin that binds the cellulose fibers. Kraft pulping is the majorform of chemical wood pulping in the United States, accounting for approximately 85 percent of pulp production, 1 and is expected to continue as the dominant pulping process. 2,3 Semi-chemical and acid sulfite pulping constitute 6 and 4 percent of domestic pulp production, respectively. 1 Four processes associated with the pulp and paper industry have been identified as potential sources of arsenic emissions: chemical recovery furnaces, smelt dissolving tanks, lime kilns, and power boilers. The following sections focus on the pulp mill thermal chemical recovery processes associated with potential arsenic emissions. Arsenic emissions from wood waste and fossil fuel-fired industrial power boilers are not specific to the pulp and paper industry and are discussed in Sections 4.1.1 and 4.1.2. 6.1 Kraft Recovery Furnaces And Smelt-Dissolving Tanks 6.1.1 Process Description The kraft pulping process involves the cooking or digesting of wood chips at an elevated temperature (340 to 360°F) and pressure (100 to 135 psig) in white liquor, which is a water solution of sodium sulfide (Na^S) and sodium hydroxide (NaOH). The lignin that binds the cellulose fibers is chemically dissolved by the white liquor in a tall, vertical digester. This process breaks the wood into soluble lignin and alkali-soluble hemicellulose and insoluble cellulose or pulp. A typical kraft pulping and recovery process is shown in Figure 6-1. 4 6-1 NONCONDENSABLES WUt6 WOd DIGESTER o CD Uh >- DC UJ > o u UJ w 00 u U O C£ Cl E 00 Ud Z < H U < Z & C ^ -J o O oo u- ^ oo DC O h- U < uj Z o oo C/D 5 UJ y z w oo c* < VO UJ OQ < E- Q H uj 2 00 o [2 M C *s O ca CC CA w a « -J C CQ •2 e % 2 1 2 w s &£2 « _ l- C l> .— > < 1> u > 1> Q c o U 1> o La 3 O CO c _o "53 C/2 UJ JS E 3 z u u co rj- CO rr wo Cl CO UJ i> X) X L> CO aS £ T3 C ca CL CO UJ CL CO UJ 1> > o u d cc ca i_i oc La o c3 o Cl ca > UJ aa o H3 a—» C o O i> — <-> a 2 a e 5 do a Urn U u. O cS Urn a C3 > UJ o 1> 2 ca c P O 3 <-> if U 11 La '•5 3 O Z a: t-~ O t co r- o i CO x © 2 to E 1) a id c >. .22 D > O o D 1> E CO wo o r- o I CO 00 •a CA 1> o c i> La ,11 ■a— 1> 1> o La 3 o CO c o u o H T3 1) E 3 X CO J m CA ;o o CA L- o 3 cr LL O ca c o ■*-- c o 1> CL •o u £ > b ~ u 1) o >» ^ — W II CL CO UJ 6-8 TABLE 6-2. DISTRIBUTION OF KRAFT PULP MILLS IN THE UNITED STATES (1997) State Number of Mills Alabama 14 Arizona 1 Arkansas 7 California 2 Florida 7 Georgia 12 Idaho 1 Kentucky 2 Louisiana 10 Maine 7 Maryland j 1 Michigan 3 Minnesota 2 Mississippi 6 Montana 1 New Hampshire 1 New York 1 North Carolina 6 Ohio 1 Oklahoma 1 Oregon 7 Pennsylvania 3 South Carolina 6 Tennessee 2 Texas 6 Virginia 4 Washington 6 Wisconsin 4 Total 124 Source: Reference 6. 6-9 Potential Emissions c ® 9 0 §1 cr o 2 3 *£ ■o *2 3 2 2 0 U. 6-10 Source: Reference 5. 100 to 400 feet in length. Lime kilns predominantly fire natural gas, with some units firing distillate and/or residual fuel oil. Many facilities incinerate non-condensible gases (NCG) from pulping source vents in lime kilns to control total reduced sulfur (TRS) emissions. Temperatures in the kiln can range from 300 to 500 °F at the upper or wet end to 2,200 to 2,400 °F at the hottest part of the calcination zone near the lower or dry end. 5,9 Emissions of concern from lime kilns include PM, largely in the form of calcium salts. Some of the PM also contains arsenic. Emissions of arsenic from lime kilns are likely due to the arsenic content of the lime mud with some contribution from the combustion of fossil fuel (natural gas or fuel oil). The most common PM control technologies used on lime kilns are scrubbers (some ESPs are also used). Scrubbers on lime kilns use either fresh water or clean condensates from pulping sources as a scrubbing medium. Small amounts of caustic solution may be added to the scrubbing solution to scrub TRS & S0 2 . Lime kiln scrubber designs include impingement, venturi, and cyclonic scrubbers. 10 6.2.2 Emission Factors Arsenic emission factors for uncontrolled and scrubber-controlled lime kilns are presented in Table 6-3. 6,7,11 6.2.3 Source Locations Lime kilns are primarily located at kraft process pulp mills. See Table 6-2 in Section 6.1 for kraft pulp mill source locations reported in 1997. 6.3 Sulfite Recovery Furnaces 6.3.1 Process Description Although not as commonplace, the acid sulfite pulp production process is similar to the kraft process except that different chemicals are used for cooking. Sulfurous acid is used in place 6-11 TABLE 6-3. ARSENIC EMISSION FACTORS FOR LIME KILNS see Control Average Emission Factor Emission Number Emission Source Device in lb/MMton BLS a Factor Rating Reference 3-07-001-06 Lime Kiln None 4.68x1 O' 7 b . U 11 Scrubber 14.5 D 7,8 a Emission factors in lb per million ton of black liquor solids generated of the mill. To convert to kg per million metric tons (kg/MMtonne), multiply by 0.5. b Emission factors in lb per air dry ton of pulp produced. of a caustic solution to dissolve wood lignin. To buffer the cooking solution, a bisulfite of sodium, magnesium, calcium, or ammonium is used. Digestion occurs under high temperature and pressure, as in the kraft process, in either batch mode or continuous digesters. Following digestion and discharge of the pulp into an atmospheric blow pit or dump tank, the spent sulfite liquor, known as red liquor, may be treated and discarded, incinerated, or sent through a recovery process for recovery of heat and chemicals. Additionally, chemicals can be recovered from gaseous streams such as those from red stock washers. The cost of the soluble bases, with the exception of calcium, makes chemical recovery economically feasible. 1,5 A simplified process schematic of magnesium-based sulfite pulping and chemical recovery is shown in Figure 6-5. Chemical recovery in the sulfite process involves the concentration of weak red liquor in multiple effect evaporators and DCEs to strong red liquor (55 to 60 percent solids). This liquor is sprayed into a furnace and burned, producing steam for mill processes. When magnesium-based liquor is burned, magnesium oxide is recovered from the flue gas in a multicyclone. The collected magnesium oxide is then water-slaked and used as circulation liquor in a series of venturi scrubbers designed to absorb S0 2 from the flue gas to form bisulfite solution for use in the cook cycle. Several processes for chemical recovery from sodium-base liquor are based upon the combustion of concentrated liquor in a kraft-type recovery furnace. The resultant smelt is similar in composition to that produced by combustion of kraft liquor. The commercial approaches to convert sodium-base smelt chemicals into regenerated cooking liquor include Sivola-Lurgi, 6-12 Potential POM Emissions Recovery Furnace/ Absorption Stream Exhaust u u c < u C c o U u o t- 3 O 00 c _o 'ts> CA UJ 4J XI E 3 z u u oo © X «s Tf rr I VO T © *x os © 3 PN m (L> C o Z C/5 E •o c ra J C/3 PO o C/3 C/5 4J O O Os Os O ha 3 O 00 CO -'T >% X >5 a. 3 E CO .x _4J 3 o ■-I 60 00 .X C OJ > c o u o H 3 a. c CO u o 3 £ 2 2 u. CO eo hi 4) > < 4> O > 4> D o U ON 4> O L_ 3 O C/5 3 _o to c UJ 4> X) E 3 z u u oo UQ r~ © x o SO SO o X m m U- u. 3 U. I i J § 2 o is >> 4> U Oi 4> X — to .£■< "3 2r c CO CTJ C c s 4> > 3 O U CJ ha Q >i hi eo O 04 tn O i ro 2 r- D Q p» o X o V) 04 -C vO © x o 4) 3 O Z tt. u. CO X 3. to < ■W o ac o I » x . 9 * "3 E .— u oc .x 8 O c 4) > 3 O o O H TD 4) 4> 3 ■a o c5 h. 4) 8 O o CO X CL to eo 3 O & ■8 4) Sa< Chi Q/ o co X 4> — T3 3 ^ co g Li .3 O __ o CO ciS ' C 7-15 7.4 Abrasive Grain Processing Abrasive grain manufacturers produce materials for use by bonded and coated abrasive product manufacturers to make abrasive products. 7.4.1 Process Description The most commonly used abrasive materials for abrasive grain manufacturing are silicon carbide and aluminum oxides. These synthetic materials account for as much as 80 to 90 percent of the abrasive grains produced domestically. Other materials used for abrasive grains are cubic boron nitride (CBN), synthetic diamonds, and several naturally occurring minerals such as garnet and emery. The use of garnet as an abrasive grain is decreasing. CBN is used for machining the hardest steels to precise forms and finishes. The largest application of synthetic diamonds has been in wheels for grinding carbides and ceramics. Natural diamonds are used primarily in diamond-tipped drill bits and saw blades for cutting or shaping rock, concrete, grinding wheels, glass, quartz, gems, and high-speed tool steels. Other naturally occurring abrasive materials (including garnet, emery, silica sand, and quartz) are used in finishing wood, leather, rubber, plastics, glass, and softer metals. 11 Silicon carbide is manufactured in a resistance arc furnace charged with a mixture of approximately 60 percent silica sand and 40 percent finely ground petroleum coke. A small amount of sawdust is added to the mix to increase its porosity so that the CO formed during the process can escape freely. Common salt is added to the mix to promote the carbon-silicon reaction and remove impurities in the sand and coke. During the heating period, the furnace core reaches approximately 4,000°F, at which point a large portion of the load crystallizes. At the end of the run, the furnace contains a core of loosely knit silicon carbide crystals surrounded by unreacted or partially reacted raw materials. The silicon carbide crystals are removed to begin processing into abrasive grains. Fused aluminum oxide is produced in pot-type electric arc furnaces with capacities of several tons. Before processing, bauxite, the crude raw material, is calcined at about 1,740°F to 7-16 remove both free and combined water. The bauxite is then mixed with ground coke (about 3 percent) and iron borings (about 2 percent). An electric current is applied and the intense heat, on the order of 3,700°F, melts the bauxite and reduces the impurities that settle to the bottom of the furnace. As the fusion process continues, more bauxite mixture is added until the furnace is full. The furnace is then emptied and the outer impure layer is stripped off. The core of aluminum oxide is then removed to be processed into abrasive grains. CBN is synthesized in crystal form from hexagonal boron nitride, which is composed of atoms of boron and nitrogen. The hexagonal boron nitride is combined with a catalyst such as metallic lithium at temperatures in the range of 3,000°F and pressures of up to 1,000,000 pounds per square inch (psi). - Synthetic diamond is manufactured by subjecting graphite in the presence of a metal catalyst to pressures in the range of 808,000 to 1,900,000 psi at temperatures in the range of 2,500 to 4,500°F. Figure 7-4 presents a process flow diagram for abrasive grain processing. 11 Abrasive grains for both bonded and coated abrasive products are made by graded crushing and close sizing of either natural or synthetic abrasives. Raw abrasive materials first are crushed by primary crushers and then reduced by jaw crushers to manageable size, approximately 0.75 inches. Final crushing is usually accomplished with roll crushers that break up the small pieces into a usable range of sizes. The crushed abrasive grains are then separated into specific grade sizes by passing them over a series of screens. If necessary, the grains are washed in classifiers to remove slimes, dried, and passed through magnetic separators to remove iron-bearing material before they are again closely sized on screens. This careful sizing is necessary to prevent contamination of grades by coarser grains. Sizes finer than 250 grit are separated by hydraulic flotation and sedimentation or by air classification. 7-17 PM emissions © A i i Figure 7-4. Flow Diagram for Abrasive Grain Processes Source: Reference 11. 7-18 7.4.2 Emission Control Techniques Fabric filters preceded by cyclones are used at some facilities to control PM emissions from abrasive grain production. This configuration of control devices can attain controlled emission concentrations of 37 micrograms per dry standard cubic meter (0.02 grains per dry standard cubic foot) and control efficiencies in excess of 99.9 percent. Little other information is available on the types of controls used by the abrasives industry to control PM emissions. However, it is assumed that other conventional devices such as scrubbers and electrostatic precipitators can be used to control PM emissions from abrasives grain and products manufacturing. 11 7.4.3 Emission Factors Little information is available on emissions from the manufacture of abrasive grains and products. Emissions from the production of synthetic abrasive grains, such as aluminum oxide and silicon carbide, are likely to consist primarily of PM, PM 10 , and CO from the furnaces. Aluminum oxide processing takes place in an electric arc furnace and involves temperatures up to 4,710°F with raw materials of bauxite ore, silica, coke, iron borings, and a variety of minerals that include chromium oxide, cryolite, pyrite, and silane. This processing is likely to emit fluorides, sulfides, and metal constituents of the feed material. The primary emissions from abrasive grain processing consist of PM and PM 10 from the crushing, screening, classifying, and drying operations. PM is also emitted from materials handling and transfer operations. Table 7-5 presents an arsenic emission factor developed from the results of a metals analysis conducted on a rotary dryer controlled by a wet scrubber in an abrasive grain processing facility. 11 7-19 TABLE 7-5. ARSENIC EMISSION FACTOR FOR ABRASIVE GRAIN PROCESSING see Number Emission Source Control Device Average Emission Factor in lb/ton a Emission Factor Rating 3-05-035-05 Rotary Dryer: Sand Blasting Grit Wet Scrubber ‘ 2.40x10^ E Source: Reference 11. a Emission factor is expressed in lb of pollutant emitted per ton of grit fed into dryer. To convert to kg per metric ton (kg/tonne), multiply by 0.5. 7.4.4 Source Locations The abrasives industry is composed of approximately 400 companies throughout the United States engaged in abrasive grain manufacturing, bonded abrasive product manufacturing, and coated abrasive product manufacturing. 11 However, the majority of the arsenic emissions from abrasive grain manufacturing come from the primary silicon carbide and aluminum oxide production facilities, and less than ten of these facilities are currently in operation in the United States. 12,13 The locations of these facilities are shown in Table 7-6. 7.5 Portland Cement Production Most of the hydraulic cement produced in the United States is Portland cement—a mixture primarily composed of calcium silicates, aluminates, and aluminoferrites. There are four primary components in Portland cement manufacturing: raw materials handling, kiln feed preparation, pyroprocessing, and finished cement grinding. Pyroprocessing, the fuel intensive process accomplished in cement kilns, has been identified as a potential source of arsenic emissions and constitutes the primary focus of this chapter. 14 7-20 TABLE 7-6. 1995 U.S. PRIMARY ABRASIVE GRAIN MANUFACTURER LOCATIONS BY STATE State No. of Facilities Illinois 1 Massachusetts 2 New York 3 Source: References 12,13. 7.5.1 Process Description Figure 7-5 presents a basic flow diagram of the Portland cement manufacturing process. The process can be divided into four major steps: raw material acquisition and handling, kiln feed preparation, pyroprocessing, and Finished cement grinding. 14 The initial step in the production of Portland cement manufacturing is raw materials acquisition. Calcium, which is the element of highest concentration in Portland cement, is obtained from a variety of calcareous raw materials, including limestone, chalk, marl, sea shells, aragonite, and an impure limestone known as “natural cement rock.” The other raw materials—silicon, aluminum, and iron—are obtained from ores and minerals such as sand, shale, clay, and iron ore. Arsenic is expected to be present in the ores and minerals extracted from the earth. The only potential source of arsenic emissions from raw material acquisition would be due to wind-blown particulate-containing arsenic from the quarry operations. Arsenic emissions are expected to be negligible from these initial steps in Portland cement production. 14 The second step involves preparation of the raw materials for pyroprocessing (thermal treatment). Raw material preparation includes a variety of blending and sizing operations designed to provide a feed with appropriate chemical and physical properties. The raw material processing differs for wet processes and dry processes. At facilities where the dry process is used, the moisture content in the raw material, which can range from less than 1 percent to 7-21 < 3 o £ e 05 .05 ’> 05 Q c o u OJ u 1-1 3 o e/3 C/5 C/5 E UJ 05 x E 3 z u u e /5 Q U b X o fN o o b. Cl >5 I— o VO o I o o co O UJ V5 I o X o (N C/5 C/5 05 8 u- CU er Q UJ «/■> o X o (N W5 o X o m U. u. CL e/j UJ 05 re 05 X o> _3 0 C /5 C /5 2 bn 05 0 ) y 3 0 u. 0 CL re £ 0 05 1 — C CU a uj W5 I o x o fS v> o 'x o m U. u. a. c /3 UJ C/5 C/5 C/5 V CJ o > Xi >5 3. "E E 05 00 3 O _ o o S 05 E xi b* T 8. u o 3 60 -X C 05 > 3 O o o H o 05 L CL O ^ S 2 in ."3 O U. U O .Si £ £ UJ re U< II " II Oh C/3 U. UJ U* 7-27 TABLE 7-9. PORTLAND CEMENT PRODUCTION FACILITIES (1995) Company Location No./type of kiln Clinker Capacity (tons/yr) Alabama Blue Circle, Inc. Calera, AL 2-dry 594 Holnam, Inc. Theodore, AL 1-dry 1,438 Lehigh Portland Cement Leeds, AL 1-dry 700 Medusa Cement Co. Demopolis, AL 1-dry 809 National Cement Co. of Alabama Ragland, AL 1-dry 944 Arizona Ash Grove Cement Co. Foreman, AZ 3-wet 883 California Portland Cement Rillito, AZ 4-dry 1,150 Phoenix Cement Co. Clarkdale, AZ 3-dry 630 California Calaveras Cement Co. Redding, CA 1-dry 649 Calaveras Cement Co. Tehachapi, CA 1-dry 900 California Portland Cement Colton, CA 2-dry 748 California Portland Cement Mojave, CA 1-dry 1,239 Kaiser Cement Corp. Cupertino, CA 1-dry 1,603 Mitsubishi Cement Corp. Lucerne Valley, CA 1-dry 1,702 National Cement Co. of California Lebec, CA 1-dry 647 Riverside Cement Co. Oro Grande, CA 7-dry 1,177 Riverside Cement Co. Riverside, CA 2-dry 110 RMC Lonestar Davenport, CA 1-dry 799 Southdown, Inc. Victorville, CA 2-dry 1,530 Colorado Holnam, Inc. Florence, CO 3-wet 837 Holnam, Inc. Fort Collins, CO 1-dry 496 Southdown, Inc. Lyons, CO 1-dry 430 Eorlda Florida Crushed Stone Brooksville, FL 1-dry 602 Pennsuco Cement Co. Medley, FL 2-wet 953 Rinker Portland Cement Corp. Miami, FL 2-wet 543 Southdown, Inc. Brocksville, FL 2-dry 1,212 Georgia Blue Circle, Inc. Atlanta, GA 2-dry 614 Medusa Cement Co. Clinchfield, GA 1-wet. 1-dry 795 7-28 TABLE 7-9. PORTLAND CEMENT PRODUCTION FACILITIES (1995)(CONTINUED) Company Location No./type of kiln Clinker Capacity (tons/yr) Iowa Holnam, Inc. Mason City, LA 2-dry 919 Lafarge Corp. Bufalo, LA 1-dry 927 Lehigh Portland Cement Mason City, LA 1-dry 804 Idaho Ash Grove Cement Co. Inkom, ID 2-wet 259 Illinois Centex La Salle, LL 1-dry 576 Dixon-Marquette Dixon, EL 4-dry 521 Lafarge Corp. Grand Chain, IL 2-dry 1,159 Lone Star Industries Oglesby, IL 1-dry 574 Indiana Essroc Materials Logansport, IN 2-wet 453 Essroc Materials Speed, IN 2-dry 1,013 Lehigh Portland Cement Mitchell, IN 3-dry 729 Lone Star Industries Greencastle, LN 1-wet 723 Kansas Ash Grove Cement Co. Chanute, KS 2-wet 484 Lafarge Corp. Fredonia, KS 2-wet 384 Monarch Cement Co. Humboldt, KS 3-dry 672 RC Cement Co., Inc. Independence, KS 4-dry 299 Kentucky Kosmos Cement Co. Kosmosdale, KY 1-dry 778 Maryland Essroc Materials Frederick, MD 2-wet 372 Independent Cement Corp. Hagerston, MD 1-dry 519 Lehigh Portland Cement Union Bridge, MD 4-dry 990 M^in? Dragon Products Co. Thomaston, ME 1-wet 431 Michigan Holnam, Inc. Dundee, MI 2-wet 1,054 Lafarge Corp. Alpena, MI 5-dry 2,267 Medusa Cement Co. Charlevoix, MI 1-dry 1,273 St. Marvs Cement Corp. Detroit, MI 1-wet 649 7-29 TABLE 7-9. PORTLAND CEMENT PRODUCTION FACILITIES (1995)(CONTINUED) Company Location No./type of kiln Clinker Capacity (tons/yr) Missouri Continental Cement Co., Inc. Hannibal, MO 1-wet 597 Holnam, Inc. Clarksville, MO 1-wet 1,297 Lafarge Corp. Sugar Creek, MO 2-dry 505 Lone Star Industries Cape Giradeau, MO 1-dry 1,188 RC Cement Co., Inc. Festus, MO 2-dry 1,269 Mississippi Holnam, Inc. Artesia, MS 1-wet 476 Montana Ash Grove Cement Co. Montana City, MT 1-wet 301 Holnam, Inc. Three Forks, MT 1-wet 350 fclevad^ Ash Grove Cement Co. Louisville, NE 2-dry 927 New M^xicp Rio Grande Cement Corp. Tijeras, NM 2-dry 475 New York Blue Circle, Inc. Ravena, NY 2-wet 1,692 Glens Falls Cement Co., Inc. Glens Falls, NY 1-dry 509 Independent Cement Corp. Catskill, NY 1-wet 658 Ohio Lafarge Corp. Paulding, OH 2-wet 501 Southdown, Inc. Fairborn, OH 1-dry 598 Oklahoma Blue Circle, Inc. Tulsa, OK 2-dry 649 Holnam, Inc. Ada, OK 2-wet 598 Lone Star Industries Pryor, OK 3-dry 684 Oregon Ash Grove Cement Co. Durkee, OR 1-dry 524 Pennsylvania Allentown Cement Co., Inc. Blandon, PA 2-dry 948 Armstrong Cement & Sup. Corp. Cabot, PA 2-wet 323 Essroc Materials Nazareth, PA 1-dry 1,174 Essroc Materials Nazareth, PA 4-dry 583 Essroc Materials Bessemer, PA 2-wet 575 7-30 TABLE 7-9. PORTLAND CEMENT PRODUCTION FACILITIES (1995)(CONTINUED) Company Location No./type of kiln Clinker Capacity (tons/yr) Pennsylvania (continued! • Giant Cemenet Holding, Inc. Bath, PA 2-wet 601 Kosmos Cement Co. Pittsburgh, PA 1-wet 384 Lafarge Corp. Whitehall, PA 3-dry 870 Lehigh Portland Cement York, PA 1-wet 99 Medusa Cement Co. Wampum, PA 3-dry 673 RC Cement Co., Inc. Stockertown, PA 2-dry 911 South Carolina Blue Circle, Inc. Harleyville, SC 1-dry 745 Giant Cement Holding, Inc. Harleyville, SC 4-wet 867 Holnam, Inc. Holly Hill, SC 2-wet 1,064 §Qyth Dakota Dacotah Cement Rapid City, SD 2-wet, 1-dry 893 Tennessee RC Cement Co., Inc. Chattanooga, TN 2-wet 438 Southdown, Inc. Knoxville, TN 1-dry 638 Texas Alamo Cement Co. San Antonio, TX 1-dry 846 Capitol Aggregates, Inc. San Antonio, TX 1-wet, 1-dry 839 Holnam, Inc. Midlothian, TX 1-dry 1,117 Lehigh Portland Cement Waco, TX 1-wet 85 Lone Star Industries Sweetwater, TX 3-dry 485 North Texas Cement Midlothian, TX 3-wet 851 Southdown, Inc. Odessa, TX 2-dry 526 Sunbelt Cmenet Corp. New Braunfels, TX 1-dry 980 Texas Industries Midlothian, TX 4-wet 1,258 Texas Industries New Braunfels, TX 1-dry 847 Texas-Lehigh Cement Co. Buda, TX 1-dry 1,103 Utah Ash Grove Cement Co. Nephi, UT 1-dry 789 Holnam, Inc. Morgan, UT 2-wet 317 Virginia Roanoke Cement Co. Cloverdale, VA 1-dry 946 7-31 TABLE 7-9. PORTLAND CEMENT PRODUCTION FACILITIES (1995)(CONTINUED) Company Location No./type of kiln Clinker Capacity (tons/yr) Washington Ash Grove Cement Co. Seattle, WA 1-dry 747 Holnam, Inc. Seattle, WA 1-wet 446 West Virginia Capitol Cement Corporation Martinsburg, WV 3-wet 955 Centex Femley, WV 2-dry 480 Royal Cement Co., Inc. Logandale, WV 1-dry 195 Wyoming Centex Laramie, WY 2-dry 644 Source: Reference 20. 7.6 Open Burning Of Scrap Tires 7.6.1 Process Description Approximately 240 million vehicle tires are discarded annually. 21 Although viable methods for recycling exist, less than 25 percent of discarded tires are recycled; the remaining 175 million are discarded in landfills, stockpiles, or illegal dumps. 22 Although it is illegal in many States to dispose of tires by open burning, fires often occur at tire stockpiles and through illegal burning activities. These fires generate a huge amount of heat and are difficult to extinguish (some tire fires continue for months). Arsenic is a component of tires and is emitted from the combustion of these tires. 7.6.2 Emission Factors Table 7-10 contains emission factors for the open burning of tires. 22 The average emission factor presented represents the average of tests performed on the simulated open burning of chunk (defined as one-quarter or one-sixth of an entire tire) and shredded tires. When estimating emissions from an accidental tire fire, note that emissions from burning tires are generally dependent on the bum rate of the tire. A greater potential for emissions exists at lower bum rates, such as when a tire is smoldering rather than burning out of control. 22 Besides accidental or illegal open burning of tires, waste tires are incinerated for energy recovery and disposal purposes. Tires are combusted at tire-to-energy facilities, cement kilns, tire manufacturing facilities, and as supplemental fuel in boilers. No emission factors for arsenic from tire incineration have been located. 7.6.3 Source Location Open burning of scrap tires can occur at permitted landfills that stockpile scrap tires, at closed landfills that already contain scrap tires, and at illegal dumpsites where tires are discarded. 7-33 TABLE 7-10. ARSENIC EMISSION FACTORS FOR OPEN BURNING OF SCRAP TIRES see Number Emission Source Control Device Average Emission Factor in . lb/1000 ton a Emission Factor Rating 5-03-002-03 Simulated Open Burning of Chunk Automobile Tires None l.OOxlO' 1 C Simulated Open Burning of Shredded Automobile Tires None 4.00x10"* C Source: Reference 23. a Emission factors are expressed in lb of pollutant emitted per 1000 ton of waste incinerated. To convert to kg per 1000 metric tons (kg/1000 tonnes), multiply by 0.907. The fires can start by accident or are intentionally set by arsonists, and thus are unpredictable as to where and when they will occur. 7.7 Grain Milling Milling is the process of converting grain into flour by mechanical means. The grain is cleaned and a small amount of water is added to prevent the outer part of the kernel from pulverizing. The moistened grain is mechanically crushed slightly and sheared into chunks. The product is sifted to remove the germ and the bran, and the chunks are size separated. The larger chunks are recrushed and the intermediate-sized chunks are ground between smooth rolls . 23 Finally, screens are used to remove undersized and oversized materials, and the final product is transferred to the bagging area, to storage, or to bulk load-out. The modem milling industry applies many innovations in their process operations. One example is the production of free-flowing flour made by agglomerating the flour particles into clusters by the addition of moisture and spray-drying. This allows for the separation of high protein and high-starch fractions and permits a wide range of custom blending . 24 7-34 Limited arsenic emissions data are available for this category. One report from tests conducted at a rice milling plant was available for review and emission factors developed from that report are presented in Table 7-11. Another test conducted at a feed mill under the California AB 2588 (“Hot Spots”) program reported that arsenic was not detected from the baghouse discharge or milling operations. 24 7.8 Process Heaters A process heater is similar to an industrial boiler in that heat liberated by the combustion of fuels is transferred by radiation and convection to fluids contained in tubular coils. Process heaters are used in many chemical manufacturing operations to provide steam and heat input essential to chemical processing. They are also used as feed preheaters and as reboilers for some distillation operations. The fuels used in process heaters include natural gas, refinery offgases, and various grades of fuel oil. Gaseous fuels account for about 90 percent of the energy consumed by process heaters. There are many variations in the design of process heaters depending on their application. In general, the radiant section consists of the bumer(s), the firebox, and tubular coils containing the process fluid. Most heaters also contain a convective section in which heat is recovered from hot combustion gases by convective heat transfer to the process fluid. Process heaters (and boilers) are most applicable where the potential exists for heat recovery from the combustion of the vent stream. For example, vent streams with a high VOC concentration and high flow rate can provide enough equivalent heat value to act as a substitute for fuel that would otherwise be needed. Emissions data for this category are limited. Emission factors developed from three available test reports are presented in Table T-ll.*" 5,26 ' 2 " 7 7-35 TABLE 7-11. ARSENIC EMISSION FACTORS FOR GRAIN MILLING O re tu 60 C = - O re 'co OC W cj 60 l— ns 2 S o 2 re u* £ c _o CO CO w u re U. .2 c co O CO — £ £ w c CJ 60 re u> cj > < cj cj > cj c c c U cj CJ I— 3 O 00 c _o 'co co 1 tU CJ U x U E 00 3 z D D o o x x o vo Tr (N vO © r~ o X X O »/o — OV — ON VO o X o CO vO b X o (N CJ CJ c g o o Z Z CO c B Q CJ CJ _o _u 0£ 0 i 60 60 C c i 1 c c CT3 re u 6 co Tf r-~ r~ 8 8 fN rs| o O co co 60 c w-j CN cj cj c cj t— .CJ Cl— cj e* CJ CJ I— 3 o c/o wo o >v X _>» o. 3 £ c o CJ o H •o CJ CO CO CJ Q. c 're C— 60 C o CJ o. •o CJ E CJ a — o X T3 CJ co CO CJ t- C- X CJ CJ u. re CO k> © o c2 c _o '55 CO E tu 7-36 TABLE 7-12. ARSENIC EMISSION FACTORS FOR PROCESS HEATERS 4> 3 4> k. ,4> C*—. 4) 2 00 g-S O ra 'co cc co •— i_ c 2 w 2 u- u oo c ra O CQ u 2 t2 g c x .2 ~ in co s uj c o ra co 3 | u® | 2 2 4> ra 2 £ > .2 < £ 8 1 5 u Q u o 3 _o u 3 •o o co ra O •a c ra a> £5 aj •o s u 2 ra a r- «s VO b X o PO VO o X o 00 rn vO o x o ra k» 4> c 4> o co 3 T3 jC E 3 2 "o u> 4> Cu vO O i ro 00 cs vO I o X VO «ri i r- o X o r-~ Ov o X o «n rs 4> 4> 4) 3 3 3 O O O z Z Z CO 4> .3 I Oi CO ~ I— - 4> t' ra ra 3 rs CO 4) 2 C .2 o 3 ■g 4) a CO CO 4> 8 u. Cu •o 4) £ O O CO CS u •o 4> 0> a w o 8 Ui Ou •o 4> m o. *3 E 2 'oc ■w 2 3 o 3 oo 4) 2 4> CL ra i_i oo o 4) > C o O o f- 3 CL c ra u j: u_ O 3 m c o 8. •o 2 E 4> 8. L— o X) T3 4» CO CO 4) M CL X 4> 4) a CO O a <4— C .2 m CO ■'?' to ■ • — o >> JO E UJ 7-37 7.9 Cotton Production and Ginning Until 1993, arsenic acid (H 3 As0 4 ) was used as a cotton desiccant in some areas of the U.S. Its use has contributed to arsenic emissions to the atmosphere both from the field where the cotton was grown and from cotton gins. Prior to mechanical stripping (harvesting) of cotton, the green leaves must be dried to prevent fiber staining and to prevent unacceptable moisture levels in the fiber. Such conditions lower the quality of the cotton. In many cotton producing areas a killer frost occurs before harvest, thus desiccating the leaves. However, in areas without such a frost, a chemical desiccant is needed. Texas and Oklahoma are the primary areas where chemical desiccation has been practiced. The use of arsenic acid as a cotton desiccant began in 1956 and continued through 1993 when it was banned from use by the EPA. 28 In practice, about 3 pints of arsenic acid per acre was applied by ground or aerial spraying. It has been estimated that only about 5 percent of the arsenic acid reached the intended crop. The remaining overspray either drifted from the field or was deposited in field soil. Sources of potential arsenic emissions to the atmosphere have included application overspray; arsenic-containing dust and plant matter emitted during harvesting; arsenic-containing dust, plant matter, and lint emitted during ginning; and wind blown soil from fields where spraying has been conducted. 29 Since the use of arsenic acid as a cotton desiccant has been banned, the emissions potential has been largely eliminated. In some areas where spraying has occurred over many years, it is possible that arsenic accumulated in the soils could still be emitted as windblown dust. However, that potential will continue to diminish over time. Limited arsenic emissions data for cotton ginning were available in the literature; however, these data are eighteen to twenty years old, and were generated from tests at a cotton 7-38 gin which received cotton treated with arsenic acid. The ginning process has changed since that time, and the data are deemed no longer applicable and are therefore not included in this document. 7-39 References for Section 7.0 1. Eastern Research Group, Inc. Clean Air Act, Section 112(k) Candidate Pollutants , draft report. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Visibility and Ecosystem Protection Group, 1996. 2. U.S. EPA. Compilation of Air Pollutant Emission Factors , 5th ed. (AP-42), Vol. I: Stationary Point and Area Sources, Section 11.15: Glass Manufacturing. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, 1995. 3. Drake, R A. Glass Technical Institute. San Diego, CA. Letter to Dennis Beauregard. U.S. U.S. Environmental Protection Agency. Research Triangle Park, North Carolina, October 1997. i 4. Factor Information Retrieval System Version 4.0 (FIRE 4.0). Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1995. 5. AP-42, 5th ed., op. cit., note 2. Section 2.4, Landfills, 1995. 6. California Air Resources Board. Source Emissions Testing of Landfills Boiler and Flare System. Confidential Report No. ERC-3. 7. AP-42, 5th ed., op. cit., note 2. Section 11.1, Mineral Products Industry, 1995. 8. U.S. EPA. Second Review of New Source Performance Standards for Asphalt Concrete Plants. EPA-450/3-85-024. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, October 1985. 9. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 724. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 10. Factor Information Retrieval System Version 3.0 (FIRE 3.0), Record Number 247. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1994. 11. AP-42, 5th ed., op cit., note 2. Section 11.31, Bonded Abrasive Products, 1995. 12. Holston, R. (Radian International, LLC) and G. Pressbury (U.S. Department of Commerce). Telecon. March 22, 1996. 7-40 13. Holston, R. (Radian International, LLC) and A. Wherry (Abrasive Grain Association). Telecon. March 22, 1996. 14. AP-42, 5th ed., op. cit., note 2. Section 11.6, Portland Cement Manufacturing, 1995. 15. U.S. Environmental Protection Agency. Emission Factor Documentation for AP-42, Section 11.6, Portland Cement Manufacturing. Research Triangle Park, North Carolina. 1995. 16. Hawkins, G. Potland Cement Association. Skokie, Dinois. Letter to Dennis Beauregard. U.S. Environmental Protection Agency. Research Triangle Park, North Carolina. October 31, 1997 17. U.S. EPA. Locating and Estimating Air Emissions from Sources of Lead and Lead Compounds, Draft. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, June 1995. 18. U.S. EPA. Technical Support for Revision of the Hazardous Waste Combustion Regulations for Cement Kilns and Other Thermal Treatment Devices, Second Draft. Prepared by Energy and Environmental Research Corporation, Irvine, California, W T ashington, D.C.: U.S. Environmental Protection Agency, Office of Solid Waste, May 17, 1994. 19. Rigo, H.G. Rigo & Rigo Associates, Inc., Berea, OH. Teleconference with P. Marsosudiro, Eastern Research Group, Morrisville, North Carolina. April 6, 1998. 20. Portland Cement Association. U.S. and Canadian Portland Cement Industry: Plant Information Summary. Skokie, IL: Portland Cement Association, 1996. 21. Lemieux, P.M. and J.V. Ryan. Characterization of Air Pollutants Emitted from a Simulated Scrap Tire Fire. Journal of the Air and Waste Management Association, 43(#)pp. 1106-1115, August 1993. 22. AP-42, 5th ed., op. cit., note 2. Section 2.5, Open Burning, 1995. 23. Austin, G.T. Shreve's Chemical Process Industries, 5th edition, Chapter 25: Food and Food By-Product Processing Industries. 1984. pp. 446-447. 24. Hargrove, K.L., Farmer's Rice Cooperative, to R. A. Isom, Fresno County. Transmittal of AB-2588 Air Toxics Emission Report. Rice Drying. September 11, 1990. 25. Radian 1993. TOX_D_EF, Record 324, Composite of 24 tests on 8 units; CARB 2588 data. June 11, 1995. 7-41 26. Pope & Steiner Environmental Services for Texaco Trading and Transportation, Inc. AB-2588 Testing at Texaco Trading and Transportation, Inc. Panoche Station, Volumes I, II, and HI. Report PS-90-2187. (WSPA) September 1990. 27. Southern California Edison Company. Emissions Inventory Testing at Huntington Beach Generating Station, Fuel Oil Heater No. 2. CARNOT. Rosemead, California. May 1990. 28. Federal Register, Volume 58, No. 139. Thursday, July 22, 1993. p. 39205. Arsenic Acid; Receipt of Request to Cancel; Cancellation Order. U.S. Environmental Protection Agency. 58 FR 39205. 29. U.S. EPA. Preliminary Study of Sources of Inorganic Arsenic. EPA-450/5-82-005. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, August 1982. 7-42 SECTION 8.0 SOURCE TEST PROCEDURES Arsenic emissions can be measured by a number of methods. The following methods are applicable for measuring emissions of arsenic in ambient air and arsenic contained in stack gas emissions: (1) National Institute of Occupational Safety and Health (NIOSH) Method 7300, 1 (2) NIOSH Method 7900, 2 (3) NIOSH Method 7901(4) NIOSH Method 5022, 3 (5) EPA’s Methodology for the Determination of Suspended Particulate Matter in the Atmosphere (High-Volume Method), Appendix B, and Appendix G modified Methodology for the Determination of Lead in Suspended Particulate Matter Collected From Ambient Air (40 CFR 50), 4 (6) EPA Method 29, 5 (7) EPA Method 108, 6 (8) EPA BIF Method, Section 3.0, 7 (9) California Air Resources Board (CARB) Method 423, 8 and (10) CARB Draft Method 436m. 9 All of the NIOSH methods and EPA 40 CFR 50 Appendixes apply to the collection and analysis of arsenic from ambient air. EPA Method 29 and BIF, Section 3.0, are part of the Boiler and Industrial Furnace (BEF) Regulations and are used to sample for total inorganic and organic arsenic, and other metals, in stack gases. EPA Method 108 and CARB Method 423 are used to sample specifically for inorganic and organic arsenic in stack gases. CARB Draft Method 436 is used to sample for total inorganic and organic arsenic, and other metals, in stack gases. Sections 8.1 and 8.2 of this report summarize the field sampling procedures for measuring arsenic in ambient air and stack gases, respectively. Section 8.3 describes the different analytical techniques used to analyze and measure the amount of arsenic collected in ambient air and stack gas samples. 8-1 8.1 Ambient Air Sampling Methods Ambient air concentrations of arsenic can be measured using Methodology for the Determination of Suspended Particulate Matter in the Atmosphere (High-Volume Method) and modified Methodology for the Determination of Lead in Suspended Particulate Matter Collected From Ambient Air; and NIOSH Methods 7300, 7900, 7901 and 5022. The following methods are described in detail below. 8.1.1 Methodology for the Determination of Suspended Particulate Matter in the Atmosphere (High-Volume Method) and Modified Methodology for the Determination of Lead in Suspended Particulate Matter Collected from Ambient Air A high Volume sampler is used to collect total suspended particulate (TSP) matter. Figure 8-1 shows a simplified diagram of the components of the high-volume ambient air sampling equipment. 10 The equipment is mounted in an enclosed shelter equipped with a roof. Ambient air is drawn under the roof of the shelter through a pre-weighed glass-fiber filter. The high-volume sampler should be operated for 24 hours at an average flow rate of 1.7 cubic meters per minute (m 3 /min). The approximate concentration range of the method is 2 to 750 pg/m 3 . However, the lower limit is determined by the sensitivity of the balance used in the analysis by the laboratory, and the upper limit is affected by various factors, such as variability of filters used in the sampler, and particle size distribution of the sample. After sampling, the filter is removed and sent to a laboratory for analysis. The method is then modified to prepare and analyze the high-volume filter sample for arsenic instead of lead. The filter is weighed several times until a constant weight is obtained and then the filter is digested in an acid solution and analyzed for total arsenic content either by atomic absorption spectrophotometry (AAS) or inductively coupled plasma (ICP) emission spectroscopy. 8-2 Glass Fiber Filter Figure 8-1. Components of a High-Volume Ambient Air Sampler for Arsenic Source: Reference 10. 8-3 ERG LE3.Cdi One advantage of the High-Volume Method (Appendix B) and the Appendix G Modified Lead Method is that the ambient air sample is collected over a 24-hour period, which can encompass all types of weather conditions, particularly temperature changes, and the range of emission source activities that occur throughout a 24-hour period. One disadvantage of the high-volume sampling method is that it was designed for sampling only total inorganic arsenic compounds in suspended particulate matter (PM). Inorganic arsenic cannot be speciated and most organic arsenic compounds cannot be detected. A second disadvantage is that the high-volume method is very dependent on meteorological conditions. Any change in wind speed or direction and any amount of precipitation can influence the sample results. To interpret the effects of weather conditions on the sample results, meteorological data must be recorded during the sampling period. 8.1.2 NIOSH Method 7300 - Methodology for the Determination of Elements by Inductively Coupled Plasma (ICP) Method 7300 can be used to sample for elemental arsenic and various metals in ambient air. This method collects particulate metals only. Samples are collected on a mixed cellulose ester membrane filter (MCEF), 0.8 pm pore size, 37 mm diameter, with a backup pad, placed into a cassette filter holder. A calibrated personal sampling pump is used to pull air through the cassette holder at a flow rate between 1 and 4 L/min for a total sample size of 200 to 2,000 L. The filters and backup pads, housed inside the cassette, are sent to the laboratory for analysis. At the laboratory, the filters are ashed using a nitric acid/perchloric acid solution and diluted to a known final volume. After the initial sample preparation step, samples are analyzed by ICP or AAS at the specific wavelength for arsenic analysis. Samples collected using NIOSH 7300 are relatively stable, but it is important not to exceed a filter loading of approximately 2 mg of total dust. 8-4 8.1.3 NIOSH Method 7900 - Methodology for the Determination of Arsenic and Compounds, as Arsenic, using Direct-Aspiration (Flame) Atomic Absorption Spectroscopy (AAS) Method 7900 can be used to sample for arsenic in ambient air. This method collects only particulate arsenic and is an elemental analysis, not compound specific. Samples are collected on a MCEF, 0.8 pm pore size, 37 mm diameter, with a backup pad, placed into a cassette filter holder. A calibrated personal sampling pump is used to pull air through the cassette holder at a flow rate of between 1 and 3 L/min for a total sample size of 30 to 1,000 L. The filters and backup pads, housed inside the cassette, are sent to the laboratory for analysis. At the laboratory, the filters are ashed using a nitric acid/perchloric acid solution and diluted to a known final volume. After the initial sample preparation step, samples are analyzed for arsenic by direct-aspiration (flame) AAS. Samples collected using NIOSH 7900 are relatively stable if refrigerated, but it is important not to exceed a filter loading of approximately 2 mg total dust. Again, this method collects particulate arsenic only and not volatile organic arsenic compounds, such as arsenic trioxide. 8.1.4 NIOSH Method 7901 - Methodology for the Determination of Arsenic Trioxide, as Arsenic, by Graphite Furnace Atomic Absorption (GFAA) Method 7901 can be used to sample for particulate arsenic compounds as well as arsenic trioxide vapor. Samples are collected on treated MCEFs, 0.8 pm pore size, 37 mm diameter, and a cellulose backup pad, placed into a cassette filter holder. The filter and backup pad is previously treated with a sodium carbonate/glycerol solution. A calibrated personal sampling pump is used to pull air through the cassette holder at a flow rate of between 1 and 3 L/min for a total sample size of 30 to 1,000 L. The filters and backup pads, housed inside the cassette, are sent to the laboratory for analysis. At the laboratory, the filters and backup pads are digested on a hot plate using 8-5 concentrated nitric acid and 30 percent hydrogen peroxide. The samples are then diluted to a known final volume. After the initial sample preparation step, samples are analyzed for arsenic by GFAA. Samples collected using NIOSH 7901 are relatively stable, but it is important not to exceed a filter loading of approximately 2 mg total dust. 8.1.5 NIOSH Method 5022 - Methodology for the Determination of Organo-Arsenic Compounds by Ion Chromatography (IC)/Graphite Furnace Atomic Absorption (GFAA) Method 5022 can be used to sample for particulate organo-arsenic compounds. Samples are collected on a polytetrafluoroethylene (PTFE) backed membrane filter, 1 pm pore size, 37 mm diameter, with a backup pad, placed into a cassette filter holder. A calibrated personal sampling pump is used to pull air through the cassette holder at a flow rate between 1 and 3 L/min for a total sample volume of 50 to 1,000 L. The filters and backup pads, housed inside the cassette, are sent to the laboratory for analysis. At the laboratory, the filter is sonicated and extracted in a sodium carbonate/sodium bicarbonate/sodium borohydride solution. The samples are then analyzed for organo-arsenic compounds by IC/GFAA. 8.2 Stationary Source Sampling Methods Various methods are available for sampling stack gas concentrations of arsenic: EPA Method 29, EPA Method 108, EPA BEF Method, and CARB Methods 423 and Draft 436. These methods are described in this section. 8-6 8.2.1 EPA Method 29 - Determination of Metals Emissions from Stationary Sources EPA Method 29 can be used to sample PM and total inorganic and organic arsenic compounds isokinetically from stack gases. The sampling train for Method 29 is a modification of the EPA Method 5 11 sampling train, and is shown in Figure 8-2. 12 Particulate arsenic with a particle size diameter greater than or equal to 0.3 pm is collected through a glass nozzle and probe onto a pre-weighed glass fiber filter. Particulate arsenic with a particle size diameter less than 0.3 pm and arsenic compounds in the vapor phase pass through the filter and are collected in a dilute nitric acid/hydrogen peroxide solution contained in the train impingers. The nozzle/probe and both halves of the filter holder are washed with dilute nitric acid. The nozzle/probe wash, two separate filter holder washes, filter, and impinger solution are sent to a laboratory, where they are digested in an acid solution and analyzed for arsenic content either by AAS or ICP. The samples collected on the filter and in the impinger solution can be analyzed separately to differentiate between the amount of particulate arsenic and arsenic in the gaseous phase. The exact run time and volume sampled varies from source to source depending on the required detection limit. Typically, the Method 29 train is run for 2 hours and collects approximately 2.55 m 3 of stack gas. According to the method, the ICP analytical detection limit is 53 ng/ml of total arsenic, and the GFAA analytical detection limit is 1 ng/ml. The upper range can be extended considerably by diluting the sample prior to analysis. However, actual sample analytical detection limits are sample dependent and may vary due to the sample matrix. Also, laboratory instrumentation may affect the detection limit. Although it is the preferred method for sampling stack gas streams and can measure several metals at one time, the method cannot be used to speciate inorganic or organic arsenic compounds. 8-7 Glass Filter Holder Thermometer h e E o ® r LJ 10 o E 3 3 O e > e. a 2 6 e 0 £* Q 04 CC ci u i— 3 o c/3 8-10 Figure 8-3. EPA Method 108 and CARB Method 423 Sampling Train 8.2.4 CARB Method 423 - Methodology for the Determination of Particulate and Gaseous Inorganic Arsenic Emissions from Stationary Sources CARB Method 423 can be used to sample PM and total inorganic and organic arsenic compounds isokinetically from stack gases. The Method 423 sampling train is similar to EPA Method 5 sampling train, and is identical to the Method 108 sampling train, see Figure 8-3. CARB Method 243 sampling and analytical procedures are identical to Method 108; refer to Section 8.2.2 for the discussion. 8.2.5 CARB Draft Method 436 - Determination of Multiple Metals Emissions from Stationary Sources Draft Method 436 can be used to sample PM and total inorganic and organic arsenic compounds isokinetically from stack gases. The sampling train for Draft Method 436 is a modification of the EPA Method 5 sampling train, and is identical to EPA Method 29 (see Figure 8-2). Draft Method 436 sampling, analytical procedures, and analytical detection limits are identical to EPA Method 29; refer to Section 8.2.1 for the discussion. 8.3 Analytical Techniques For The Measurement Of Arsenic The most common technique for measuring total arsenic in samples is spectroscopy. The two spectroscopic techniques used most by environmental laboratories are AAS and ICP. AAS is the most common method used to measure total arsenic. The advantages to AAS are that the method is simple, rapid, and applicable to a large number of metals. Samples other than drinking water must be acid-digested prior to analysis. Three types of AAS methods for measuring total arsenic are direct aspiration (flame), graphite furnace, and hydride-generation. 8-11 The second most common technique for measuring total arsenic in samples is ICP, which allows simultaneous, or sequential, determination of several metals in a sample during a single analytical measurement. Samples must be acid-digested prior to analysis. Although not as common, another technique for measuring arsenic in samples is ion chromatography (IC) connected to GFAA. 8.3.1 Direct Aspiration (Flame) Atomic Absorption Spectroscopy (AAS) Method 7000 13 specifies the procedure for analyzing samples using direct-aspiration (flame) AAS. In direct-aspiration (flame) AAS, a sample is aspirated and atomized in an air/acetylene flame. A light beam from a hollow cathode lamp, whose cathode is made of the element being measured, is directed through the flame into a monochromator, and onto a detector that measures the amount of light absorbed. Absorption depends upon the presence of free, unexcited ground-state atoms in the flame. Because the wavelength of the light beam is characteristic of only the element being measured, the light energy absorbed by the flame is a measure of the concentration of that element in the sample. With flame AAS, if the proper flame and analytical conditions are not used, chemical and ionization interferences can occur. Flame AAS in normally performed as a single element analysis. If direct-aspiration (flame) AAS techniques do not provide adequate sensitivity, graphite furnace techniques can be used. 8.3.2 Graphite Furnace Atomic Absorption (GFAA) Spectroscopy Method 7060 13 specifies the procedure for analyzing samples for total arsenic using graphite furnace AAS. The principal of graphite furnace AAS is essentially the same as for direct-aspiration (flame) AAS, except a furnace rather than a flame is used to atomize the sample. In graphite furnace AAS, a representative aliquot of a sample is placed in a graphite tube in the furnace, evaporated to dryness, charred, and atomized. The radiation from a given excited element is passed through the vapor containing ground-state atoms of that element. The intensity of the transmitted radiation decreases in proportion to the amount of the ground-state element in the vapor. The metal’s atoms to be measured are placed in the beam of radiation by increasing 8-12 the temperature of the furnace, thereby causing the injected sample to be volatilized. A monochromator isolates the characteristic radiation from the hollow cathode lamp or electrodeless discharge lamp, and a photosensitive device measures the attenuated transmitted radiation. The major advantage of GFAA is that it affords extremely low detection limits. It is the easiest technique to perform on relatively clean samples. Because this technique is so sensitive, however, interferences can be a problem; finding the optimum combination of digestion, heating times, and temperatures, and matrix modifiers can be difficult for complex matrices. 8.3.3 Inductively Coupled Plasma (ICP) Atomic Emission Spectroscopy Method 6010 13 specifies the procedures for analyzing samples using ICP. The ICP method measures element-emitted light by optical spectrometry. The sample is nebulized and the resulting aerosol is transported to the plasma torch, where excitation occurs. Characteristic atomic-line emission spectra are produced by radio-frequency inductively coupled plasma. The spectra are dispersed by a grating spectrometer, and the intensities of the lines are monitored by photomultiplier tubes. The photocurrents from the photomultiplier tubes are processed and controlled by a computer. The primary advantage of ICP is that it allows simultaneous or rapid sequential determination of many elements in a short time. The primary disadvantage is background radiation from other elements and the plasma gases. Although all ICP instruments utilize high-resolution optics and background correction to minimize these interferences, analysis for traces of metals in the presence of a large excess of a single metal is difficult. 8.3.4 Hydride Generation Atomic Absorption (HGAA) Spectroscopy Method 7061 13 specifies the procedure for analyzing samples for total arsenic using HGAA. HGAA utilizes a chemical reduction to reduce and separate arsenic selectively from a digested sample along with standard AAS techniques. 8-13 The primary advantage of this technique is that arsenic can be isolated and quantitated from complex samples. A disadvantage of HGAA is that significant interferences will occur when easily reduced metals are present, and/or when high concentrations of transition metals are present. Also, oxidizing agents, such as oxides of nitrogen, may remain after the sample has been digested. 8.3.5 Ion Chromatography (IC)/GFAA NIOSH Method 5022 specifies the procedure for analyzing air samples for total arsenic using an IC connected to GFAA. Ion chromatography is a separation technique used for the analysis of ionic species. Separation of components in a sample can be achieved with the use of a mobile phase (eluent), and a stationary phase (a specific type of polymeric resin bed inside of a column). A sample analyte is introduced into the flowstream of the mobile phase (eluent) and is carried onto the stationary phase (column). The analyte then undergoes a separation process based on its affinity for either of the mobile or stationary phases. With NIOSH Method 5022, the IC detector is bypassed, and the sample flows into an arsine generator where gaseous arsines are formed. A gas-liquid separator is then used to flow the sample into the GFAA where the sample is quantitated. 8-14 References for Section 8.0 1. National Institute for Occupational Safety and Health. NIOSH Method 7300. NIOSH Manual of Analytical Methods, 3rd edition. Cincinnati, Ohio: U.S. Department of Health, Education, and Welfare, February 15, 1984. 2. National Institute for Occupational Safety and Health. NIOSH Method 7900. NIOSH Manual of Analytical Methods, 3rd edition. Cincinnati, Ohio: U.S. Department of Health, Education, and Welfare, August 15, 1987. 3. National Institute for Occupational Safety and Health. NIOSH Method 5022. NIOSH Manual of Analytical Methods, 3rd edition. Cincinnati, Ohio: U.S. Department of Health, Education, and Welfare, May 15, 1985. 4. U.S. Code of Federal Regulations. Title 40, Protection of the Environment, Part 50, Appendix B—Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High-volume Method). Washington, D.C.: U.S. Government Printing Office,-1994. 5. U.S. EPA. Methodology for the Determination of Metals Emissions in Exhaust Gases from Hazardous Waste Incineration and Similar Combustion Sources, 3rd ed., Test Methods for Evaluating Solid Waste: Physical/Chemical Methods, Method 12. SW-846. Washington, D.C.: U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, September 1988. 6. U.S. Code of Federal Regulations. Title 40, Protection of the Environment, Part 61, Appendix B—Method 108, Determination of Particulate and Gaseous Arsenic Emissions. Washington, D.C.: U.S. Government Printing Office, 1991. 7. U.S. EPA. Test Methods for Evaluating Solid Waste. Report No. SW-846. EPA Draft Method 0012 - Multi-Metal Train. EPA/530-SW-91-010. U.S. Environmental Protection Agency, Office of Solid Waste, December 1990. 8. California Air Resources Board. Stationary Source Test Methods, Volume III: Methods for Determining Emissions of Toxic Air Contaminants from Stationary Sources. Method 423. Sacramento, CA: California Air Resources Board, September 12, 1987. 9. California Air Resources Board. Stationary Source Test Methods, Volume III: Methods for Determining Emissions of Toxic Air Contaminants from Stationary Sources. Method 436. Sacramento, CA: California Air Resources Board, March 24, 1992. 10. U.S. EPA. APTI Course 435 Atmospheric Sampling, Student Manual. EPA 450/2-80-004. Research Triangle Park, North Carolina: U.S. Environmental Protection Agency, September 1980. pp. 4-38 and 4-51. 8-15 11. U.S. Code of Federal Regulations. Title 40, Protection of the Environment, Part 60, Appendix B--Method 29, Determination of Metals Emissions from Stationary Sources. Washington, D.C.: U.S. Government Printing Office, 1994. 12. U.S. Code of Federal Regulations. Title 40, Protection of the Environment, Part 60, Appendix A: Methodology for the Determination of Metals Emissions in Exhaust Gases from Incineration and Similar Combustion Sources (Draft), Method 29. Washington, D.C.: U.S. Government Printing Office, 1992. 13. U.S. EPA. Test Methods for Evaluating Solid Waste , Volume LA: Lab Manual of Physical/Chemical Methods. Report No. SW-846. U.S. Environmental Protection Agency, September 1986. 8-16 APPENDIX A EMISSION FACTOR SUMMARY TABLE ' TABLE A-l. SUMMARY OF EMISSION FACTORS BY SOURCE CLASSIFICATION CODES G # o U. 60 ’5 2 .5 C/5 CJ — *3 co co UJ uu cd U U 4> CQ On o o co CJ b o 'co C/i UJ © *x o ■'T ri vO © x o tt o *x o cq co u> o > < a •I 2 CO c_> ‘5 E uj UJ v> o x o oo oo vi o x o oo od VI b X o oo od r- l O X r* 00 m o X O oo od V) o X O oo od VI o X o wo C o Z 4> c o Z X) 2 £ •w 4) £ x: | — 2 UJ ^ I 3 *-• O £ x: C/3 < cj >v c_> 3 < a >v C j= CO uj 3 UJ x: ■2 o 2 c o «J W o J ^ £ ££ w u 4) -= a |. 2 w O .3 T3 > '5 (U 3 O 4) 3 C § .S — 4> 3 i 3 cj Z Z o cd u 00 w 3 O 3. o W 4) 3 'ST 2 *5 cd n. 3 2 JJ o a. vs •— CJ x; oj s •§ Cd c0 CQ 4) 4> u. 3 O in 3 .2 CO co E UJ •a o o ■8 o £ ■a o o £ CO CQ JJ ‘5 CQ •a 4> u. £ 4> co e0 2 'o CQ X3 V b> £ ■ 4) W5 CO CQ id id id 3 co id 3 CO ^4J 3 cO 2 3 CO 2 ‘o A ‘3 2 '5 4) ’o 2 '3 2 ’5 2 "5 2 CQ CQ to CQ CO CQ to CQ to CQ t 5 CQ CO •o •n ■o £ T3 ;D ■a £ ■o ;£ ■a £ ■a ;3 41 k> £ i 4> N CO CO 4) i— £ In CO CQ •a 4) •a 4> •8 •- -8 -8 .is >> 5c CJ > CJ :> CJ w to 4J 4> o co WO co ^ A 4> Urn V o C/5 •o 4> Um £ § 4> q co WO C0 £ A •a a U« £ 8 4J o CO W0 co £ fj Ui u. o o CJ U. 81 § g £ £ £ £ ^ £ ^ £ u| u E CO 3 Z o I ON ro O co O i ON 8 © X o TT o X o Tf T o s fN I Q z T o T o X 3 fN rc o X X cn m rf o mi —' i i T O X fN tT >n c D c o 2 CQ g uS c o 2 CQ S c o c o c o c o c o 2 oa £ u5 2 03 2 2 jD 2 2 CQ CQ 2 !2 O T y "T T O o O o x-x v»X X X X X X O o oo TT m 00 Cv m 00 00 — mi b s 3 £ S 23 cj oo eo u. CJ > < C •2 g to w to E UJ o re uu in o X o oo oo m o x o m I © x o oo 00 VO I © X ^r m mi V m I © X o oo oo «n © X o oo 00 m o x o 00 oo cj u > oj Q c o U x: to < UJ 5 e 2 k- 4> « a> 1) x> CJ CJ CJ CJ CJ CJ CJ CJ CJ c CJ d> c x> c c c c c c c c c c o o 2 cn o o o o o o o o o o Z o -2 Jo 1> O (V u Z Z Z Z Z Z Z Z Z Z Z 2 a. 2 2 CJ C_) u- 3 O cn c .2 "So to E UJ •a o o £ cj o 2 CQ “> •a £ cj — re •a O o cj '5 CQ •a c n o* in i £ "55 3 O uu jU V ■a CT3 ■o o V •a a £ V •o' CTJ •o c3 u. CJ c CJ c3 CQ 0-> N £ i CJ u> w o CJ k. 3 CJ k. o oo c3 £ £ £ £ £ VJ u CQ re o U •a TO o U ■a 0J N • IX Ux CJ > cj 3 E 3 UU cj c ja cj >% U CJ O cn i- cj •a re cj i— a. cn 2 re ~ O oo _c > CO ”2 "2 CO 03 "2 CJ o o O o o o U U U U U «—■ cn CO E CO E CO to to 3 o 3 o 3 3 3 "O O O O O O CJ _c o CQ p o CQ c e c g 2 Wx 3 CJ 3 3 CJ > £ £ CQ a £ £ £ o U 8 U E Cn 3 Z in o 8 NO o NO o 6s 6s cfi 6s 8 8 8 8 fN fN fN fN O o © © t— o i cn fN O rs O I On m O fN o o I fN fN O i fN i © m o s I I fN fN 8 8 m O I fN A-2 TABLE A-l. CONTINUED c # o L. OO ’S3 2 .S C/3 u © *2 « re B3 UU DC u UJ uj u UJ uj UJ w w w uj uj UJ UJ UJ o GO s cc o w u. e o 3 CO UJ T o "x cs TT in I T o X s ri o © x co o "T © X Tf >n x m m b i T O X n m x o ni i cn I © x o m — m I O X o T o X oo ro in T © x o TT ni Q Z T © X n id 41 c &0 O I- 2 'Si 2 u .a o > 2 i2 < UJ c o u 41 41 41 41 41 41 41 41 41 41 41 41 41 c c C G 3 3 8 8 3 3 8 8 8 3 3 o o o O O O O O O O O O O O O z z Z z Z Z Z Z Z Z Z Z Z Z Z o> u 1— 3 O 00 3 o 3 to e UJ T3 41 _N i— 41 > CO O U E o CO w 3 O O CQ c 41 £ X -T2 •§ o cn U T3 41 N 'i— 3 Cu 3 o U CO 3 O 3 1 3 '2 X 3 00 41 3 _o U 2 o U tS co B o 01 •o C5 41 1— Cl 00 2 o U oo 41 > C3 W- u. 41 ^ -g § Co o ^ CO 41 41 £ C3 O u •o 41 N ‘C 41 > £ Q cfl O U •a 41 _N ‘C 41 > 41 £ B 3 U. 41 3 _o 3 sn U 4) «>X 03 Wx o oo c 3 > k- CQ 2 -x H 2 o CQ La 3 O 3 O 3 O u- 13 2 2 2 00 c 41 41 3 8 *§ V > o o u o U o U o U 41 X u- Q 3 2 t-x 3 41 E 4) E 4) W 41 • * X CJ c X s> X 22 ’s o ’s o 3 "E ; ofl| •a2s lO w •a w « C Ua &£ UJ UJ D D UJ u BJ BJ BJ BJ UJ BJ UJ UJ D BJ BJ 4> OO % GS u co U. a o 'S3 CO UJ CN X co © T © X cn »n t o X CN ■'T «ri T o *x s CN X co o i T O x CN tT »n T o X o cn Q Z m © X co © T O x cn cri T O X CN ■^r «n T © x s CN co w C D a £ 2 x 3 £ CD oa £ 2 2 2 CQ 2 S 3 cq 2 2 3 CQ S 2 3 CQ 2 £ a o 3 3 CQ CQ 2 2 a £ s x 5 2 CQ CQ 2 £ £ 2 a a £ £ S x 2 x o > 4> a e o u 4> c o 4> 4> i> 4) 4) 4) 4) 4) 4) *-w 4) 4> a a a a a a a a a a a a a a a o o o o o o o o o o o o o u c o Z Z Z Z Z Z Z Z Z Z Z Z Z 4) Z Z 00 e <55 4) U eo e C0 O 13 o ha 4) -X ha 4> o ha 4) lx o ► A £ T3 kx _3 4) N hJ 4» *c 4> a ha 4) •a CQ kx o E 3 Ua u •a U ■o O £ £ •o O (55 _e 13 > C0 4) a— ha 4> T3 cn 33 £ 4> > & 4) > £ 33 U co 4) ha O. cn 13 > C0 ha E— ha 4> JX o oo c 13 > 4) a _o u 4> N ‘ha 4) > 4» _N ha 4) > T3 4) <2 ha 4> 4) ,aj Cha kx 4) •o ha 4) ■o CO 4> t_ H u. a D CTJ o 13 o P W O a 13 o 13 o 13 o hi cn CO ha ha U £ £ > o a kx D- 13 41 13 U U Um o U a o U U U /“■V T3 C 4) .X 13 13 73 13 13 CQ o o o CO CO a_< CO CO CO CO 4) CO o o o o o o o U *-a 00 U 3 O 3 O o CQ 3 O o CQ 3 O 3 3 O <2 ha O u Cr> U U u U U w u co y^v CO _e a a a a 4> 4> o CO CO CO £ CO E CO CO CO 3 O _a ■o 4» <2 3 O a 3 E 3 33 £ 3 kx Q 1 3 4) 4> | | | > o •o 4) o E 2 £ IS X) 3 cn ‘S X) 3 cn 13 o U X X 3 cn o U X X 3 cn rt E 3 Ua X X 3 cn Stokei X X 3 cn 4J CO ha o ha 5 a < ha 4> > g 3 £ 3 W £ CQ 4) 3 £ CQ er Q 3 £ i £ E 3 £ T3 4> N *c o> > co 8 E U o co a a o o CQ a ^ *2 4> i I ^ x -a o CO 3 O 8 u u| U 2 Cn 3 z «n O X o CO CN CN CN CO CN TT CN >n CN CN O CO o in o 8 o oo o 8 CN CN 8 CN 8 CN 8 CN 8 CN 8 CN 8 CN 8 CN 8 8 CN 8 CN 8 fN 8 • 8 1 fN 8 i rsi 8 1 fN 8 CN O i CN O i CN o 1 CN O i CN O i CN O i CN o CN O CO o CO o i CO o i CO o i CO o cn O i CO O i CO o — 1 1 A-4 TABLE A-1. CONTINUED c ° u. OX) 'S5 2 .2 co (j S •a w re E u. o£ UQ uj UJ uj u uj w UJUJUJQQQQQ3 o x TT WO NO I NO o x 8 T o X Tf I to o "T © X Tf NO © X 8 T o X o - -SS 3 E < UJ a o u re uu NO CN — cn 1 o 1 © © © o b b b b b © i © X ’x t 1 X 1 X X 1 X X X X X X X •O" wo ! 1 ! co © ! o 8 © © 8 © r-~ oo —■ • 1 1 © • r- CN 1 uo cn 00 NO —I 0) Q c o U c _o _re 3 O QJ CJ CJ 4> 4) 4) 4) 4) 4> 4> 4) 4) 4) 4) 4) c c c 3 3 CJ 3 3 3 3 3 3 3 3 3 3 o o O O O CJ o O O O O O O O O O z z Z Z Z Om C/3 Z Z Z Z Z Z Z Z Z Z CU m UJ re O v 3 4> CJ l— 3 O m a o CO CO 2 UJ •o 4> N ‘C u > re o U CO 3 O c •3 >v E Ua 2 Q il re 3 O m U E o o CQ 0) 3 o U ”re O U CO 3 O 3 E 3 15 X) 3 0) 3 E 3 4) •a re re <- k. 4/ f-’g g ^ cj "S' CO O "re re •§ £> | £> 55 -5 s -C © U- co •— 4/ .3 DC U. O x 4) re w> Ux C o :§ — UJ O 13 1 2 12 m < o 3 4) c3 © H re E k. 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CONTINUED c ,2 Ui DO Tn CO o a _C re E tu U- DC D re tu r- "T O X VO tU LI Q tu x x 2 l> CO tu tu CL CO tU tu tu CL CO tu tu tu o tU tU LI £ c o U LI c CL LI c CL LI 50 b. i_> LI >> LI 3 o Z CO tu o Z CO tu Q >» Q ■“w O Z l l> So u li tU tU CL CO tU a o u X re V- « >> re o CO X < CL CO CL CO CL CO >3 re s lj X CL CO tu (LI 3 o Z li li LI li >3 re >3 X Q CL CO o CO >3 re c L> X CL CO tU a c o Z CL CO >3 q CL CO o CO >3 Q tu tu a >3 >3 re CL co CL CO tu l> So >3 re CL CO l> x LI X 2 E _ — M re re re 03 13 X X >• > > > 3 O CO O CL U CL LI — — CO re 3 2 3 2 LI 3 tU (L> LI 3 3 tU tU li 3 tu o so L. o o >3 b. o o co 3 X £ o U CO 3 X E o U CO 3 X E o U o CO 3 X E o CO 3 X E o U re re li re o re u re E tu •a LI > •a T3 -a LI Li LI > > > U re o re re £ re re LI DC LI DC LI oc LI QC LI DC CO 3 O •3 < < re 3 E T3 LI E: re •3 LI > LI a LI LI LI a a a CO re co LI co cE LI DC LI LI CO CO LI CO cE a a LI LI LI DC DC DC 2 O 3 00 CQ 3 X E _ o S U CO CO re t O 3 co CQ 3 co "2 « E >5 ° 2 u E S « I X E _ o S u CO CO re | 2 3 co CQ 3 X E o S U U r* Ux 2 g 2 CO CO re O 3 to CQ 3 CO -2 « E 42 o S U LI 03 £ 2 3 CQ 2 re £ E 3 m 2 re £ E 3 CQ LI 03 £ E 3 CQ 2 re £ fc* 2 re 03 £ E 3 CQ O DC re 2 re £ >> 03 O 0£ c/3 c/3 03 C/3 C/3 03 C/3 C/3 03 C/3 C/3 03 S £ S S 2 re 2 re £ Er re o DC C i; 3 b« re i- t O E o E o 3 to 3 to 3 to CQ 3 CQ 3 QQ 3 co "2 % E •5 o S u CO 2 « E ^ o 2 u co *2 « E >2 o S u u| U E CO 3 Z © i/i — —* co © © © co co co o o o 5 S S S S m O m o in in o o 1/1 o 8 8 8 8 8 8 CO O 8 8 8 8 8 8 ui o o o I I I 1/1 */1 /l wi 1/1 o in O i s OO o co CA ^ C/5 © X r~- PM m \o o o vr> o W1 o VO o co I o X r- ro x ro v u- Q a. oo W aj c o Z u. X v >3 >3 CO u< CL OO X x cl S oo .2 ^ o To .2, « S' C — Q c £ * a. o cu 00 x 1) c o z x x V- aj Q >3 eo i— a. oo CL 00 X k. ZJ CT Q >3 CO ka CL OO x X "c _o a a c a> X) k- O 00 l— Q Cl OO x 4> c o Z X X u. 4J >3 >3 CO k* CL OO 0. oo X 4> >3 >3 ca k. CL 00 UL X "e O o 4> c 4> X i— O OO CL 00 x 3 L c0 O CL E o m 3 1/3 3 S3 I 2 u cq £ U d cq £ >3 k> 2 o cl E 2 /5 00 CQ P ««-g 5/3 E « o 2 U k~ o C/3 3 X E o U VI 3 X E o U 1/3 3 X E o U C/3 3 X E o O C/3 3 X E o U < < < < < C/3 C/3 3 k- o o co 3 u. 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CO w > X X o 4) re £ CS 03 £ 03 V) 3 X E Q V) 3 X E o t? 3 X to 3 X to 3 X •te- CO 3 X> to 3 X cj u* Ui 3 4) 3 3 3 3 O CO pa £ «—> c3 c3 £ c5 U u* u u. 0 U 0 U 0 u 0 U 0 u cd 2 ca 2 g 2 u a a Urn g 2 CJ cs 2 a # o co u w O pa O re O >* u. 2 o e? ca o re i •3 OJ > re i •3 ?• 03 t C^ cr aj • CO CO cd CO CO a> 03 1 CO CO a > Ua O 03 t-a 3 w w ■§ w ’S 3 w € u 3 w X c 3 w 3 E w CtC a DC DC DC 2 £5 0 0 CJ 0 u OJ S X re re re 03 03 e £ o £ o 2 O 2 o 2 Urn o 55 X W X ffl X w X W X w .5 0 3 X 3 E 3 X 3 E 4) X = to 03 3 CQ D a 1 s to 03 3 3 03 GO 3 Ut u* ka 03 kx 03 ka t-4 u 03 C jj JJ _4J 3 _CJ 4> 1/5 3 c« H 5 o t« -2 S E J2 o to -2 to F 42 o 1/3 3 « E 42 o C/3 CO 03 X E o 3 ■8 "3 •3 0 ■3 ■8 3 •3 0 ■3 ■g "3 ■g ■3 •3 0 4) DO •3 0 D- "5 .s* 3 cx "3 .£• 3 0 . 3 O. 3 S u S U S U S U 2 U s S s 55 S S S s u* m m CO m re^ rer X X X X X 8 X X X X X X U u O -O i 8 8 8 8 8 8 i 8 8 8 X 8 X 8 X 8 X 8 X 8 1 un 8 1 8 C/D z CO O i m O CO O m o CO O CO O CO 0 CO CO 0 0 CO 0 CO 0 CO 0 0 1 0 1 0 1 0 1 0 1 0 1 0 X X X X X X X X X X X X X X X X 1 1 u-i A-8 TABLE A-1. CONTINUED c O Jr Ml ‘53 3 .2 2 o « 3 n w !“•* UJ CQ UQ D D W BJ U PJCQWUJWUJUJW 04 00 s OS o re U- c ,2 t« £ UJ «s © X CM © CM t T O x O m cm r o X o ’'T cm I T o X c D s o c o c o a o c o s o c o c o c o c o s o a o c o s o s o s o s o c o ll 1 3 oo .o 04 -a > g < UJ “ 2 o 03 a. © X o CM fn © X o 04 m b x o r- X o 7 o X o 04 CO — © X T O X o ■ 04 Q e o U c_ 00 UJ 04 g i— 04 X> X 04 00 04 H s 04 E 04 . .E x a. x E 2 “ cj on 04 w X 04 3 8 04 > £ X 2. 04 on ■Z 2 3 04 in •° £ c 04 > 3 8 04 > C 04 E 04 OO _ C E .04 — oo Jr? e 44 OO X 2 04 oo 04 c .2 04 ;o U 04 3 Cl c 04 E 04 CO C •“ •5. iS I 2 c on _2 04 >n u _04 CO 8 c/5 04 X X 2 04 oo 2 5 CL a 04 E 04 CO .£ - a. 04 2 — x ^ 2 04 04 X <40 X 2 04 oo c 04 > 04 e o Z c 04 E 04 co II II 04 04 c oo 2 >, o re >> »- U b "cb s c75 hp 04 _ X s 2 O 3 3 on U M >> £ 00 ^ fc- ts 04 8 3 04 w E £ CO S •£ — 1 cl E 04 04 & & H H 3 8 04 04 E E 04 . 04 OC ■ E X 3 CL X ’EL >n 04 C 2 o G U. u. 3 , o c .04 3 G E 2 'a oo 04 w X 04 •° £ E x x x ^ 2 04 04 x in x 04 c o Z 04 C o Z w tU E 3 K ‘-5 . 04 X oo U- u. 04 X X 04 c .04 "o £ B3 5 04 X X CL m w .2 o 04 UL U. ~c .2 o 04 3 X c 04 c g o < 2 04 X 2 C^J 04 m X 3 CJ c^> "C *u> u w 3 3 04 04 0J 3 04 3 04 on 04 > > c 04 X I— o m >-, u. Q 3 is u- O C^J d a 04 a u. 3 O <40 3 .2 v (/) UJ o 04 04 04 04 CJ U 04 04 04 re re re re c 3 8 8 P u. t-i k> u Li D 3 3 3 3 u- UL UL U. X ’S 2 H 5 L 3 Li re re re re CJ 04 04 04 04 a: ac X X X CJ 04 JL 4 2 04 .s- a. CL • .CL "5 *3 3 3 3 S S •a •a •a T 3 •a -a 04 04 04 04 04 04 CQ CQ ffi CQ X X 3 •o 3 •a 3 T 3 3 T 3 3 •o 3 ■a .2 04 .2 04 .2 04 .2 04 .2 04 .2 04 .N N N w N «—> .N w .N re Ll 3 c 5 u- 3 c 3 Up 3 Up 3 a Up 3 Up 3 04 3 0 J 3 CJ 3 CJ 3 CJ 3 CJ 3 c c c c c o u. *o u. U u. o E 'u E o X 8 c c c c 04 04 04 04 04 04 i_ CO Uh CO Up CO Up 00 Up O 0 Up CO 04 3 T 3 3 CJ 3 •a CJ 3 •a CJ 3 •o o CJ 3 "O Z 3 CJ 3 •o _3 O 55 o ^5 O on O in O m O on id 2 -o 04 re o CC 3 O U re u ‘cb _2 o •S re CL re 04 ’cb _2 o 5 re CL CT3 CO 03 03 re 03 _o ^4 04 04 04 04 cb 00 oo OO CO Of o o o o o o d o o o 3 o 3 3 X X X X CZ re cz 03 03 Oh CL CL a. CL CL X/") K/~l «n on X X X X X X X X X X X X X t__ —* —* 'T 1 1 ^H 1 1 1 o 1 o 1 o o o o o o w 04 1 l/**) 1 1 1 on O m r-~ ex' V o X o ■'T o X o c D c o e o s o o o c o c o c o s o s o c o a o ^ 3 ■O QQ 5 s CQ ^ x ^ ■“ X 4j OX) fO 1— Oj > < 3 •2 g to ^ CO E uj o re u. in O X VO TT T O x eX m cn T O x ex rr eX o X eX VO 00 o X in Ov ro m I O X r~ ex rn m o x r- ex rn ’T O X ex ■ o ’> 4) C c o U c o X ta re U o ~C .« o c •- — o c 4> s X ha o m 4) 4) 4) 3 3 3 O O O Z Z Z u. u. >v o c .Si '3 O ha UJ 60 £ £ X u. u. *>> a c _0J 3 © Vha UJ E 3 '•3 4) 2 4) o c 4> G £ UJ £ 3 4> X X u 6> X o m 3 m ha •a a j U 4) > oo > 0- c /2 UJ ~3 .o 3 4) C 4) X ha o in >% ha o c o X ha re U U. U, "c o U. r: Z ^ £1 ““ o c -g. 4> C X ““ ha O m c 4) X ha O CO >> ha Q 4) 4) 4) 4) 4) 3 3 3 3 3 O O O O O Z Z Z Z Z 4> 4) O h. 3 O cn c _o co to E UJ c c o .•= s * a g* 3 re 2 ° £ c* c O "O — 4) re x 4) C 3 c 3 O U 3 _o re ha 4) 3 O 3 3 _o w re ha 4) 3 '3 3 3 O re ha 4) 3 3 3 3 _o re ha 4) C '3 3 3 o re ha 4> 3 '3 3 3 O re ha 4) C '3 3 3 O 4> _S '3 3 C3 13 13 03 13 re CT3 13 13 C3 O • 71 o *rr o O 4> O CJ •r? re re 3 _o re 4) C '3 3 re re 3 3 X u 60 3 E 3 CQ CO _ 4) 3 ha 4) - r — Q. H n o in O m O m O m o o o m r- see Numbe in m in *n >n >n in in >n m ex fvj 1 • 1 r- 8 8 8 8 8 8 8 8 8 8 8 8 8 ex o 8 8 o ex o rx O ex o ex O ex O ex o ex O ex O ex O ex O ro O rn o in i o * ex o m in »n in in »n in m in in in >n 1 (N • m A-10 TABLEA-l. CONTINUED c n w o c c3 3 D D D D D D D D D D D D p D D p u3 CL CL • 4> 60 o o O o cs o 3 60 O « « 2 S •- y > £ £ < uj vO b X o C4 *r T - o o o x Tf ON X o 04 x o un X O (N —• NO — V fS I O X O NO Un m tj- © o X X s 8 rs cs 7 o X © on 8 UL U- 3 3 O z UL CL -C Urn OJ O Z u. ul o c .Si o £ te¬ rn E ‘•3 4> X) X 2 o on 4> g X UL CL u. C/5 o c J2 *o >5 U u QJ 2 3 X e_ 4> 2 u- 3 4) 4> 3 ^ *£ CL 4) 4> 4) 4> 44 3 3 8 3 3 3 8 O O O O O O O Z Z Z Z Z Z Z CL on uu CL on UJ 4) O i— 3 O on 3 .2 C/5 E CL) CD OJ u CO 5 § e X 60 X l| X oo -a s c '5 •3 re 2 .2 O U JLJ 3 o l— 4> C k. 3 X 44 *- 4) 60 re >- o on "re C/5 C/5 4) 8 i— CL 4) 4> a W 4) £ E 3 U- 60 c 4) 44 re E 3 CL _ c/3 C <6 on 3 4> CT3 2 c O 60 ~CAj 3 C/5 X ‘2 pj S re = 2 •p 60 3 ’ 5 ) H re x U 4) § E 3 c/5 /—v 4) 60 E x 'a. 60 a. 3 re CL H C/5 4) i E 3 ul o U- 3 4) > 4> X •a § C/D CT3 £ E 3 CL w oo re 60 3 '2 X 4> CL 4> 4) 4) £ E 3 CL *-» C/D CS CQ CQ CQ 60 .3 *W 4) CL E w Ln + S QC a. co a! ul 5g £5 + 3 QC .5 S £ 2 w 3 O C/5 C/5 cu 4) ’So 3 CL 44 c 4> > 3 O U 4) > 60 3 UL 4> 44 re E 3 UL fc* O C5 c/D c x .2 k> 05 05 > *2 4) 3 CL UJ 00 re O CL ■o 4> CQ •a 41 _N jo jS CL 2 05 re o CL re 4> X 4> 2 ”S E on >5 k. o re O0 ^ l T! <4— re I fe x ~ 3 4) ° 2 D * § & o o re w -. u- oj i— 44 ii 4) C' r 44 ^ — CL •£ 4» 4) -P 4) w 4) 05 ■g > re s 4> O CL CL > 4) 05 3 > re O 4) O U CL CL 05 3 O re k- 3 eq C 3 O U 4) £ 4) > 3 O U CD U x u E on 3 Z ON ON ON r- ON ON | ON | i r* O on 8 O 8 1 fN O c n O S 5 s 1 rn rn rn r«n m s s I I <*“) m wn tT ON rsl on s on 8 04 o O O O un wn un un un un un un un 8 8 8 8 8 8 8 8 8 8 Tf m on rn on on on on m O O O o O O O o o o m m on on on on on on on A-l 1 TABLE A-1. CONTINUED ' c o kx 60 "S3 CO 1 UJ o w u 03 Ux c 3 06 D D D X D D D 3 D D D D D UJ D D Q UJ Q • aj 60 q i o 1 1 1 1 1 1 1 1 1 1 o 1 00 t o 1 • o » 1 l l 1 1 c o o o o b o o O o *—* o *-x f-4 *-x X X X X X X X X X X X X r- CO X CO 8 8 o o IT © TT CO r- vo ON r- co X CO X o m UJ r-- b Tf r-' tJ- CO — yf V V (N S - CO c c c c c c c c sT CQ c c c c c C c c c o o o o o o o o o o o o o o o o o 2 XX D X X X X X X X X X X X X X X X X X "■* X X X X VO O o CS o O T vO o t o r- o o r* o \0 T T 0) c o O o o o o o oo o u- x—- ^x x-x X- «x X-X x-x *— xX XX XX XX XX XX XX CQ o X X X X X X X X X X X X X X X X kx CO o ! ! ! ! ! < £ UJ CQ u. i i 1 1 1 -% OJ c o “ Ux J5 X p a> CO 0> CO u. 3 u. .3 ^ kx a/ X Xi Q 3 O X CJ cn k aj X 3 o X k aj X cj 00 3 O X U U c o aj c o CJ 00 aj c o 3 O X CJ c o 3 O X U- [I. ^ .2 aj y aj c o Ux fT E CJ Cl c n O kx C 60 CQ CO k. P E OJ 60 (Q CQ E CQ X *kx S 60 CQ m CJ a Z Z D •w Z 60 CQ CQ Z 60 CQ 02 C CJ 5 ‘c 1 Z on 3 UJ o U C aj > u >% CQ U >> CQ c > 3 S c aj > >s « u a aj cL CL Q. 00 00 3 £ CJ > w 5 c CO CO XX CO C CO C ‘5) t CJ k < cj Qx o- C C cd kx o 4> _o 3 k 3 oo C c o U # o ’co 3 u. < 60 c 3 u. E w 00 + L« rv CO "c3 C e CL CL 60 _c CJ k 3 O <73 c _o 3 c/3 kx 0> xx CO 03 O C* •o CO E UJ 4> > ’5) 1 CJ % £ 3 U. >> 60 c 60 _c 60 c aj £ E 3 U. aj £ E 3 u. aj i E 3 U. - Landfills CJ 3 *8 k CL 2 4J - Cupola - Cupola o c aj > c o U .2 c aj > c o U 3 X CL D3 < o X 3 X CL C/3 < XX o re to £2 CO •o s 00 E < CJ CQ T3 CD _N jo 3 u. k* O a. u. b E* o CJ CJ CO 2? k kx c o 60 E ■xj CO O «— 03 kx jS i— CO C *co CO U £ >* _7 kx T* Is kx *-x Q "eb 3 Q 'So c E 3 Q ~60 c 1 3 < ‘C o aj kx < CJ kx s kx < O k o aj o CO CO § •a 2 CQ O * k X CQ a> CJ c kx D ■o c 3 if c o T3 C 3 if C o Q S' k o >% k Q CQ O aj >» k Q E E aj k Q E E >% kx Q >> lx CT3 o CO CJ 8 kx Ox £r U u. DC DC UJ a. 2 CQ CQ CQ UJ UJ UJ Cl u. u. kx lx 06 06 Q D QC D kx 3 8 m Tjr ^r cs 8 8 8 o CN O (N O os Os 00 OS o o O o «n o >n o in o 8 see .8 E in 8 i m 8 in 8 i »n 8 in 8 8 8 8 r~ 8 r^ 8 r> 8 8 8 CO 8 m 8 8 8 n o * >n o i in o • in o m co m CO ro CO m co CO ro m CO CO ro m i cn i m 1 A-12 TABLE A-1. CONTINUED c o Ui BO CO co O u G *3 CS co u UU CX QQQQQUUQUQ UJ QUO D Q < UJ «o O X n O X wi o X o O X ir> i O X in i o X w-> i O X VO O X TT i o Csl r~~ 00 o o O O o o o o TJ- »n y-X Cn! CN 00 (N CO CN CO CN CO CM CO ro rV o —* — — — — — —* — —' 2 ^ « 21 SO TT co 4> u > 4) Q U. U. t_ gj £ o H x u c u 3 uj u. c _o o >> U jj . 2 - 3 2 uj uj c_ on UJ UJ u- a. on UJ uu uj Cl. on UJ u. UJ a. on UJ Cl. on UJ x X e cj on w £ ■a 3 cO a. on UJ cu on UJ 2 CO E: 4> Q 4) Urn V X) 4> G X) C O E O 00 O Z Z gj CJ u- 3 O on a _o CO CO E UJ a; g 3 "n C c £ U6 *6 CO CO gj cj O i— CJ >o l— Q CO CO 4J o o u. CJ Q CO C/D QJ 8 u. a- & js 3 CD CO O u- cu Q c 5 CO CO X 8 I— cu & Q Q C/D to OJ 8 w- cu & 4> O xs a> C/D C/D a> 8 CJ >v u. Q CS o X CD CO CO a> 8 H CU erx 4> G "o 3 cj o 2 CO gj x (U CO CO 4> CO e CO G 8 H CU Q ^ Q ^ CO CO u 8 l— CU w aj £ CO CO 8 u- cu w £ X CO o c3 U-I a > « W 8 o i CO 3 C B. © ?o t-l o c3 a« co y > « w E w 3 8 “• u 4) > O o Q cc CJ gj c o U a gj G O gj x BO C > > o o o CO CO _c _c 4) DC 5 3 X 4) 4) co £ *a3 E on E J E J gj u co 3 UJ gj > O u 4) cc 4> 3 ID U X U E on 3 Z VO o vO U~) O I m VO o I VO s s 8 S S i r- r- 8 8 i i IT) i t/0 t I/O 1 wo 1 *n 1 m 1 oo ■ wo o o O o o o o o 1 q o i CO I CO CO CO CO CO CO CO CO CO r* o rn r- o • m W1 o o i CO 8 8 i i 8 8 ■ i r- r" o o • i CO CO co o X X X X > E cs U- § ON TT 8 o cn < uu «ri . ON ■Nf oi 4) O > 4) Q c o U 4) CJ l_ 3 O 00 CO CO E UJ U & U E 00 3 Z x cs *9 o X o x o ro i © x o 00 ro S> © X vO *n i r- © x o r- ON 3 O 3 cq 2 3 <5 2 2 3 CQ s 4) 4/ 4) 4) 3 3 3 3 O O O O Z Z Z Z 4J > CO L. 4> C 4> CO 4> DC 4> co C/3 4) O o C t> .2 o _r 3 \T •o O CO 4> .3 13 CL ' « o ca U— 3 C co 2 4) O CO c u_ 3 u. o k. a. C/3 CO o CO s 4) .2 cl o !? 4) •o 2 U L- o w C3 § 2 4> , CO C 3 0 0 O X o CO CO 3 •o j= E 3 _4J o k-r 4/ CL 4) E CO CO u CO 3 J2 CO 4> u a _o o 3 ■o o 4> co 4) X CO CO 4> £ 8 C/5 O •o 4) T3 C § E 6 o m o i ro ro ro ro A-14 TECHNICAL REPORT DATA (PLEASE READ INSTRUCTIONS ON THE REVERSE BEFORE COMPLETING) 1. REPORT NO. 2. EPA-454/R-98-013 3. RECIPIENTS ACCESSION NO. 4. TITLE AND SUBTITLE LOCATING AND ESTIMATING AIR EMISSION FROM SOURCES OF ARSENIC AND ARSENIC COMPOUNDS 6. REPORT DATE 6/1/98 «. PERFORMING ORGAMZATION CODE 7. AUTHOR(S) 1. PERFORMING ORGANIZATION REPORT NO. 9. PERFORMING ORGANIZATION NAME AND ADDRESS EASTERN RESEARCH GROUP, INC P 0 BOX 2010 MORRISVILLE, NC 27560 10. PROGRAM ELEMENT NO. 11. CONTRACT/GRANT NO. 68-D7-0068 12. SPONSORING AGENCY NAME AND ADDRESS U. S. ENVIRONMENTAL PROTECTION AGENCY OFFICE OF AIR QUALITY PLANNING AND STANDARDS (MD-14) RESEARCH TRIANGLE PARK, NC 27711 13. TYPE OF REPORT AND PERIOD COVERED FINAL 14. SPONSORING AGENCY CODE 15. SUPPLEMENTARY NOTES EPA WORK ASSINGMENT MANAGER: DENNIS BEAUREGARD (919) 541-5512 16. ABSTRACT TO ASSIST GROUPS INTERESTED IN INVENTORYING AIR EMISSIONS OF VARIOUS POTENTIALLY TOXIC SUBSTANCES, THE U.S. ENVIRONMENTAL PROTECTION AGENCY IS PREPARING A SERIES OF DOCUMENTS, SUCH AS THIS, TO COMPILE AVAILABLE INFORMATION ON SOURCES AND EMISSIONS OF THESE SUBSTANCES. THIS DOCUMENT DEALS SPECIFICALLY WITH ARSENIC AND ARSENIC COMPOUNDS. ITS INTENDED AUDIENCE INCLUDES, FEDERAL, STATE, AND LOCAL AIR POLLUTION PERSONNEL AND OTHERS INTERESTED IN LOCATING POTENTIAL EMITTERS OF ARSENIC AND IN MAKING GROSS ESTIMATES OF AIR EMISSIONS THEREFROM. THIS DOCUMENT PRESENTS INFORMATION ON (1) THE TYPES OF SOURCES THAT MAY EMIT ARSENIC; (2) PROCESS VARIATIONS AND RELEASE POINTS FOR THESE SOURCES; AND (3) AVAILABLE EMISSIONS INFORMATION INDICATING THE POTENTIAL FOR ARSENIC RELEASES INTO THE AIR FROM EACH OPERATION. 17. KEY WORDS AND DOCUMENT ANALYSIS a. DESCRIPTORS ARSENIC AIR EMISSION SOURCES TOXIC SUBSTANCES EMISSION ESTIMATION b. IDENTIFIERS/OPEN ENDED TERMS c. COSAT! FIELD/GROUP 18. DISTRIBUTION STATEMENT UNLIMITED UNCLASSIFIED 21. NO. OF PAGES 278 UNCLASSIFIED 22. PRICE i