&EPA United States Office of Pollution Environmental Protection Prevention and Toxics Agency EPA/560/8-92/001 A January 1992 Pollution Prevention Options In Metal Fabricated Products Industries A Bibliographic Report Printed on Recycled Paper ------- POLLUTION PREVENTION OPTIONS IN METAL FABRICATED PRODUCTS INDUSTRIES A BIBLIOGRAPHIC REPORT January 1992 This report was developed by U.S. EPA's Office of Pollution Prevention and Toxics, under the direction of: David A. Hindin William M. Burch Special Projects Office and Daniel L. Fort Economics and Technology Division U.S. Environmental Protection Agency 401 M. Street, S.W. Washington, D.C. 20460 This report was prepared under EPA contract number No. 68-WO-0027 by Science Applications International Corporation. ------- TABLE OF CONTENTS SECTION I. INTRODUCTION Overview What is Pollution Prevention? . . . Information on Pollution Prevention Purpose of this Report Limits of this Report 1 2 3 4 5 SECTION H. OVERVIEW OF METAL FABRICATED PRODUCTS Introduction to Metal Fabricated Products Industries Wastes of Concern Metal Fabricated Products Manufacturing Processes 6 8 8 SECTION HI. METAL SHAPING OPERATIONS Metal Shaping Processes Wastes Generated General Source Reduction and Recycling Techniques 10 10 12 12 SECTION IV. SURFACE PREPARATION OPERATIONS Surface Preparation Processes Wastes Generated General Source Reduction and Recycling Techniques 16 16 17 18 SECTION V. SURFACE FINISHING OPERATIONS 25 Surface Finishing Processes 25 Wastes Generated 28 General Source Reduction and Recycling Techniques 29 SECTION VI. POLLUTION PREVENTION DOCUMENTS AND REFERENCES 42 SECTION VII. APPENDIX A Compendiums and Guides 42 Additional Pollution Prevention References 45 BIBLIOGRAPHY RELEASES OF THE 17 CHEMICALS FROM 1988 TRI DATA 52 ------- LIST OF TABLES Page Table 1. Metal Fabricated Products Industries 6 Table 2. Typical Metal Fabricated Products Operations Which May Produce Waste 9 Table 3. Metal Shaping Operations 10 Table 4. Examples of Source Reduction and Recycling Options for Metal Shaping Operations 13 Table 5. Types of Surface Preparation Operations 16 Table 6. Examples of Source Reduction and Recycling Options for Surface Preparation Operations .. 19 Table 7. Types of Surface Finishing Operations 25 Table 8. Examples of Source Reduction and Recycling Options for Plating Operations 30 Table 9. Examples of Source Reduction and Recycling Options for Finishing Operations 37 ------- POLLUTION PREVENTION OPTIONS IN METAL FABRICATED PRODUCTS INDUSTRIES: A BIBLIOGRAPHIC REPORT SECTION I: INTRODUCTION Overview The United States Environmental Protection Agency (EPA) developed this bibliographic report to assist metal fabricated products companies in implementing pollution prevention practices. This report is intended to help metal manufacturers identify and implement cost-effective pollution prevention practices to reduce or eliminate their releases of the 17 chemicals targeted for reductions in EPA's 33/50 Program. In addition, EPA developed this report to educate its own staff and State personnel on pollution prevention opportunities in these industries. EPA hopes this report also will assist the public, engineering and business students, and other interested persons in learning about pollution prevention. The 33/50 Program is EPA's voluntary pollution prevention initiative to reduce national pollution releases and off-site transfers of 17 toxic chemicals by 33 per cent by the end of 1992 and by 50 per cent by the end of 1995. The Agency is inviting companies to participate in this voluntary program by examining their own industrial processes to identify and implement cost-effective pollution prevention practices for these chemicals. The Program aims, through voluntary pollution prevention activities, to reduce releases and off-site transfers of a targeted set of 17 chemicals from a national total of 1.4 billion pounds in 1988 to 700 million pounds by 1995, a 50% overall reduction. While EPA is seeking to reduce aggregate national environmental releases of the 17 chemicals by 50 per cent by 1995, individual companies are encouraged to develop their own reduction goals to contribute to this national effort. EPA also encourages companies to reduce releases of other TRI chemicals and to extend these reductions to their facilities outside the United States. EPA will periodically recognize those companies that have committed to reduce their releases and transfers of the targeted chemicals, and publicly recognize the pollution prevention successes these companies subsequently achieve. POLLUTION PREVENTION CAN: Reduce a company's costs and legal liabilities associated with waste treatment and disposal; Reduce production costs by conserving raw materials, water, and energy; and Protect the environment and public health. ------- THE 17 CHEMICALS TARGETED FOR REDUCTIONS IN THE 33/50 PROGRAM: Benzene Cadmium and Compounds Carbon Tetrachloride Chloroform Chromium and Compounds Cyanide and Compounds Lead and Compounds Mercury and Compounds Methylene Chloride Methyl Ethyl Ketone Methyl Isobutyl Ketone Nickel and Compounds Tetrachloroethylene Toluene 1,1,1 -Trichloroethane Trichloroethylene Xylenes These chemicals were selected fronr the Toxics Release-inventory - (TRI). The TRI is a computerized data base containing public information on the annual releases and transfers of approximately 300 toxic chemicals reported by U.S. manufacturing facilities to EPA and the States. Since 1987 federal law has required facilities to report the amount of both routine and accidental releases of the 300 listed chemicals to the air, water and soil, and the amount contained in wastes transferred off-site. As required by the Pollution Prevention Act of 1990, TRI industrial report requirements will be expanded, beginning in calendar year 1991, to include information on pollution prevention. What is Pollution Prevention? Pollution prevention (sometimes referred to as source reduction) is the use of materials, processes, or practices that reduce or eliminate the creation of pollutants or wastes at the source. Pollution prevention includes practices that reduce the use of hazardous materials, energy, water or other resources, and practices that protect natural resources through conservation or more efficient use. Pollution prevention should be considered the first step in a hierarchy of options for reducing the generation of pollution. The next step in the hierarchy is responsible recycling of any wastes that cannot be reduced or eliminated at the source. Wastes that cannot be recycled should be treated in accordance with environmental standards. Finally, any wastes that remain after treatment should be disposed of safely. EPA is promoting pollution prevention because it is often the most cost-effective option to reduce pollution and the environmental and health risks associated with pollution. Pollution prevention is often cost effective because it may reduce raw material losses, reduce reliance on expensive "end-of-pipe" treatment technologies and disposal practices, conserve energy, water, chem- icals, and other inputs, and reduce the potential liability associated with waste generation. Pollution prevention is environmentally desirable for these very same reasons: pollution itself is reduced at the source while resources are conserved. Perhaps the best way to understand pollution prevention is to consider a few examples of some possible types of pollution prevention techniques and processes. (Specific examples of pollution prevention techniques that have been used successfully by metal manufacturers are described in Sections III, IV, and V of this report). Some ------- general examples of pollution prevention techniques are described below: Production Planning and Sequencing plan and sequence production so that only necessary operations are performed and that no operation is needlessly "undone" by a following operation. One example is to sort out "reject" parts prior to painting or electroplating. A second example is to reduce the frequency of cleaning equipment by painting all products of the same color at the same time. A third example is to schedule batch processing in a manner that allows the wastes or residues from one batch to be used as an input for the subsequent batch (e.g., to schedule paint formulation from lighter shades to darker) so that equipment need not be cleaned between batches. Process or equipment modification change the process, parameters or equipment used in that process, to reduce the amount of waste generated. For example, you can change to a paint application technique that is more efficient than spray painting, reduce overspray by reducing the atomizing air pressure, reduce dragout by reducing the withdrawal speed of parts from plating tanks, or improve a plating line by incorporating dragout recovery tanks or reactive rinsing. Raw material substitution or elimination replace existing raw materials with other materials that produce less waste, or a non-toxic waste. Some examples include substituting alkali washes for solvent degreasers, and replacing oil with lime or borax soap as the drawing agent in cold forming. Loss prevention and housekeeping perform preventive maintenance and manage equipment and materials so as to minimize opportunities for leaks, spills, evaporative losses and other releases of potentially toxic chemicals. For example, clean spray guns in a manner that does not damage leather packings and subsequently causes the guns to leak; or place drip pans under leaking machinery to allow recovery of the leaking fluid. Waste segregation and separation avoid mixing different types of wastes, and mixing hazardous wastes with non- hazardous wastes. This technique makes the recovery of hazardous wastes easier by minimizing the number of different hazardous constituents in any given waste stream. Also, it prevents the contamination of non-hazardous wastes. For example, segregate scrap metal by metal type, and segregate different kinds of used oils. Closed-loop Recycling - use or reuse of a waste as an ingredient or feedstock in the production process on-site. Recycling in which a waste is recovered and reused in the production process on-site as an input is a form of pollution prevention. One example is using a small on-site still to recover and re-use degreasing solvents. Training and Supervision provide employees with the information and the incentive to minimize waste generation in their daily duties. For example, this might include ensuring that employees know and practice proper and efficient use of tools and supplies, and that they are aware of, understand, and support the company's pollution prevention goals. Information on Pollution Prevention One good source of information on pollution prevention is EPA's Pollution Prevention Information Clearinghouse ("PPIC"). PPIC contains technical, policy, programmatic, legis- lative, and financial information on pollution prevention efforts in the United States and abroad. The FPIC may be reached by personal computer modem ("PIES"), telephone hotline or mail. Associated with the PPIC is the PIES, or Pollution Prevention Information Exchange System, a free 24-hour computer bulletin board consisting of message centers, technical data bases, issue-specific "mini-exchanges", and a calendar of pollution ------- prevention events. The PIES allows a user to access the full range of information in the PPIC. For information on how to use the PPIC/PIES call (703) 821-4800. To logon to the PIES system using a modem and a PC call (703) 506-1025 (set your communication software at 8 bits and no parity). Many of the documents referenced in this report are available through the PPIC/PIES. While the PPIC provides a centralized information source, you may wish to seek the guidance or help of pollution prevention experts. Some organizations that you may wish to contact include: Trade Associations - often trade associations can provide you with pollution prevention assistance directly, or they can refer you to someone who can. State Waste Management Agencies These agencies often have staff people who are knowledgeable about pollution prevention and are willing to provide assistance. Many states now have pollution prevention programs which may be able to offer information and sometimes technical assistance on pollution prevention. Regional Environmental Protection Agency Offices There are ten Regional Offices of the U.S. Environmental Protection Agency. The easiest way to find out which Regional Office is responsible for your area is to call the toll free RCRA/Superfund Hotline (see below) and ask for the telephone number or address of the Regional Office respon- sible for your area. EPA Office of Research and Development Pollution Prevention Research Branch, as (513) 569-7215 can also provide technical and engineering pollution prevention information. Environmental Protection Agency Within U.S. EPA Headquarters you may conveniently contact any of the following information sources: EPA Waste Minimization Branch, at (703) 308- 8402, can provide you with technical waste minimization information; Pollution Prevention Division, at (202) 260-3557, can assist you in understanding pollution prevention and provide a great deal of pollution prevention information; and the RCRA/Superfund Hotline, at (800) 424-9346 (or (202) 260-3000), can answer your pollution prevention questions, help you access information in PIES, and assist you in searching for and obtaining documents. A comprehensive, national listing of pollution prevention resources, documents, courses, and programs, including names and phone numbers, is contained in an annual EPA publication. Copies of this document Pollution Prevention Resources and Training Opportunities in 1992 - may be obtained by calling the PPIC/PIES support number at (703) 821-4800. Purpose of this Report This report is intended to help metal fabricated products manufacturing companies develop and implement pollution prevention practices to reduce their releases of the 17 chemicals targeted for reductions in the 33/50 Program, as well as other pollutants and wastes generated. In addition, this report is intended to assist EPA staff, state environmental agencies, and other interested persons in learning about pollution prevention opportunities. The remainder of this report provides: An overview of the various metal fabricated products manufacturing processes and the wastes they produce; A quick reference to pollution prevention options applicable to many of these processes, including summaries of economic benefits; and An annotated bibliography of references that describe additional information on potentially useful pollution prevention options, procedures, techniques, as well as waste recycling options. ------- Limits of this Report or This report provides an overview of the pollution prevention and recycling alternatives that may be available in the metal fabricated products industry. This report is only a starting point to assist the user in his or her preliminary research and development of pollution prevention options. Of course, each company remains responsible for identifying, evaluating and implementing pollution prevention practices that are appropriate for its particular situation. EPA has compiled this report as an information dissemination and exchange service. The information is intended to inform companies and the public about pollution prevention practices, options, and references. By compiling and distributing this report EPA is not recommending the use of any particular processes, raw materials, products, or techniques in any particular industrial setting. Compliance with environmental, occupational and safety and health laws, as well as all applicable federal, state, and local laws and regulations is the responsibility of each individual business and is not the focus of this document. The information contained in this report is intended to be a fairly comprehensive bibliography of the documented information on pollution prevention and recycling practices for the metal fabricated products industry. However, the collection, organization and dissemination of pollution prevention information is a relatively new undertaking, as well as an ongoing and evolutionary process. In addition, there are limits to any bibliography, including this bibliography. Thus, this bibliography may not contain every relevant article on pollution prevention and recycling for metal manufacturers. EPA encourages all users who discover, in the literature or in the field, pollution prevention options that are not cited in this report to share this information with EPA. Please submit any corrections, updates, or comments on this report to: Pollution Prevention Information Clearinghouse Science Applications International Corporation 7600-B Leesburg Pike Falls Church, VA 22043 Special Projects Office (TS-792A) Office of Pollution Prevention and Toxics U.S. EPA 401 M Street, S.W. Washington, D.C. 20460 ------- SECTION H: OVERVIEW OF METAL FABRICATED PRODUCTS INDUSTRIES Introduction to Metal Fabricated Products Industries Metal or equipment manufacturing encompasses a wide variety of industries. This report includes those industries that produce fabricated metal products. The raw materials used by these industries are metals that range from common copper and steel to expensive high grade alloys and precious metals. The metal fabricated products manufacturing processes are integral parts of aerospace, electronic, defense, automotive, furniture, domestic appliance, and many other industries. Table 1 identifies the types of industries that conduct metal fabricated products manufacturing operations (74). These industries typically utilize processes that fabricate products from ferrous and non-ferrous metal materials. There are many types of operations that are used in this category. Due to the large scope, however, this discussion will be limited to the processes that are common to the majority of the industries. This report will provide a general overview of the major processes, the wastes typically generated, and set a foundation on which to begin a pollution prevention approach. Table 1. Metal Fabricated Products Industries SIC 34 FABRICATED METAL PRODUCTS, EXCEPT MACHINERY AND TRANSPORTATION EQUIPMENT This major group includes establishments engaged in fabricating ferrous and nonferrous metal products, such as: Metal cans Tinware Handtools Cutlery General hardware Ordnance (except vehicles and guided missiles) Nonelectric heating apparatus Metal forging Metal stampings Fabricated structural metal products Metal and wire products, not elsewhere classified. ------- Table 1. Metal Manufacturing Industries (continued) SIC 35 INDUSTRIAL AND COMMERCIAL MACHINERY AND COMPUTER EQUIPMENT This major group includes establishments engaged in manufacturing industrial and commercial machinery and equipment and computers. Included are the manufacture of: Engines and turbines Metalworking machinery Farm and garden machinery Special industry machinery Construction, mining, and Computer and peripheral equipment oil field machinery and office machinery Elevators & conveying equipment General industrial machinery Hoists, cranes, monorails, industrial trucks and tractors Refrigeration and service industry machinery SIC 36 ELECTRONIC AND OTHER ELECTRICAL EQUIPMENT AND COMPONENTS, EXCEPT COMPUTER EQUIPMENT This major group includes establishments engaged in manufacturing machinery, apparatus, and supplies for the generation, storage, transmission, transformation, and utilization of electrical energy. Included are the manufacturing of: Electricity distribution equipment Electrical industrial apparatus Household appliances Electrical lighting and wiring equipment Radio and television receiving equipment Communications equipment Electronic components and accessories Other electrical equipment and supplies SIC 37 TRANSPORTATION EQUIPMENT The Transportation Equipment Manufacturing category includes all industries involved in the manufacture of equipment for transportation of passengers, and/or cargo by land, air, and water. Included in this industry are manufacturers of: Motor vehicles Aircraft Guided missiles and space vehicles Railroad equipment Miscellaneous transportation equipment, such as motorcycles, bicycles, and snowmobiles Individual vehicle systems, parts, and some related accessories Ships Boats ------- Table 1. Metal Manufacturing Industries (continued) SIC 38 MEASURING, ANALYZING, AND CONTROLLING INSTRUMENTS; PHOTOGRAPHIC, MEDICAL AND OPTICAL GOODS; WATCHES AND CLOCKS This major group includes establishments engaged in manufacturing a wide array of instruments for measuring, testing, analyzing, and controlling, and their associated sensors and accessories. Industries in this group are manufacturers of: Search, detection, navigation, guidance, aeronautical, and nautical systems, instruments, and equipment Laboratory apparatus and analytical, optical, measuring, and controlling instruments Surgical, medical, and dental instruments and supplies Ophthalmic goods Photographic equipment Watches, clocks, clockwork operated devices, and parts SIC 39 MISCELLANEOUS MANUFACTURING INDUSTRIES This major group includes establishments primarily engaged in manufacturing products not classified in any other manufacturing major group. Industries in this group fall into the following categories: Jewelry, silverware, and plated ware Musical instruments Dolls, toys, games, and sporting and athletic goods Pens, pencils, and artists' materials Buttons, costume novelties, miscellaneous notions Brooms and brushes Caskets Other miscellaneous manufacturing industries Wastes of Concern Metal fabricated products industries were selected for the 33/50 Program because these industries release significant quantities of the 17 chemicals of concern. Appendix A lists the releases associated with each of these five SICs. Appendix A demonstrates that release of chlorinated solvents and the generation of metal- and cyanide-bearing wastes are of concern for these industries. The processes responsible for these releases are described in the sections that follow. Metal Fabricated Products Manufacturing Processes Metal fabricated products manufacturing operations can be classified into three major operations: metal shaping, surface preparation and surface finishing. Each of these operations may consist of various processes used in different combinations or sequences to achieve the desired product. To understand the metal manufacturing process with respect to use and release of the 17 chemicals of concern and methods to reduce these emissions, requires an investigation of each of these types of operations and their component processes. Table 2 provides a quick reference list of the processes to be examined in the remainder of this paper. ------- Table 2. Typical Metal Fabricated Products Manufacturing Operations Which May Produce Wastes Typical Process or Operation Typical Materials Used General Types of Wastes Generated Metal Shaping Including: Machining Cutting oils Degreasing and cleaning solvents Acids Heavy metals Acid/alkaline wastes Heavy metal wastes Solvent wastes Waste oils Surface Preparation Including: Solvent Cleaning Pickling Heat Treating Acid/alkaline cleaners Organic solvents Acid/alkaline solutions Acid/alkaline solutions Cyanide salts Oils Acid/alkaline wastes Ignitable wastes Solvent wastes Still bottoms Acid/alkaline wastes Heavy metal wastes Acid/alkaline wastes Cyanide wastes Heavy metal wastes Waste oils Surface Finishing Including: Electroplating Surface Finishing Facility Cleanup Acid/alkaline solutions Heavy metal bearing solutions Cyanide bearing solutions Solvents Paint carrier fluids Cleaning solvents Acid/alkaline wastes Cyanide wastes Heavy metal wastes Plating wastes Reactive wastes Wastewaters Heavy metal paint wastes Ignitable paint wastes Solvent wastes Still bottoms Solvent wastes Still bottoms ------- SECTION HI: METAL SHAPING OPERATIONS Metal Shaping Processes Shaping operations take raw materials and alter their form to make the intermediate and final product shapes. There are two phases of shaping operations: primary and secondary. Primary shaping consists of forming the metal from its raw form into a sheet, bar, plate, or some other preliminary form (2). Examples of the most common metal shaping operations are described in Table 3. More detailed descriptions of these operations can be found in standard engineering references as well as many of the pollution prevention references listed in this document. EPA also has provided some general information on the types of wastes commonly associated with these processes. For many processes, however, EPA does not have descriptive or quantitative information concerning process wastes. Secondary shaping consists of taking the preliminary form and further altering its shape to an intermediate or final version of the product. This step typically involves operations such as: stamping, turning, drilling, cutting and shaping, milling, reaming, threading, broaching, grinding, polishing, and/or planing. These operations are primarily used to remove metal to develop a specific form from the unfinished piece. Table 3. Types of Metal Shaping Operations Process Abrasive Jet Machining Casting Cladding Description Cutting hard brittle materials through a process similar to sand blasting. Abrasive jet machining, however, can use much finer abrasives carried at high velocities (500-3000 fps) by a liquid or gas stream. The process can result in wastewater from solution dumps, spills, leaks or wash downs of work area. Wastes may contain abrasive fines, metals and oils. Filling shaped containers or molds with molten metal so that upon solidification, the shape of the mold is reproduced. Types of casting methods: stationary casting (or pig casting, air cooled in molds); direct chill casting (continuous solidification of the metal while it is being poured); continuous casting (sheet or strip); semi- continuous casting (molten metal is poured down a trough and into vertical billet molds). Creating a composite metal containing two or more layers that have been bonded together. Bonding may have been accomplished by roll bonding (co-rolling), solder application (brazing), or explosion bonding. 10 ------- Table 3. Types of Metal Shaping Operations (continued) Process Description Drawing Pulling the metal through a die or succession of dies to reduce its diameter, alter the cross-sectional shape, or increase its hardness. Typically used to manufacture tube, rod, bar, and wire. May be conducted hot or cold. Intermediate annealing is frequently required between draws to restore the ductility lost by cold working of the drawn product. Electrical Discharge Machining Removal of metal from the workpiece surface with stringent dimensional control. The machining action is caused by the formation of an electrical spark between an electrode, shaped to the required contour, and the workpiece. Rinsing of machined parts and work area cleanups can generate wastewaters which also contain base materials. These wastewaters contribute to the common metals and oily waste types. Electrochemical Machining Process based on the same principles used in electroplating except the workpiece is the anode and the tool is the cathode. Electrolyte is pumped between the electrodes and a potential applied which results in removal of the metal. In addition to standard chemical formulations, inorganic and organic solvents are sometimes used as electrolytes for electrochemical machining and with the basis material being machined, can enter waste streams via rinse discharges, bath dumps, and floor spills. Waste generated can contain metals, cyanide, and solvents depending upon specific precvs!: Electron Beam Machining Thermoelectric process whereby heat is generated by high velocity electrons impinging on part of the workpiece. At the point where the energy of the electrons is focused, it is transformed into sufficient thermal energy to vaporize the material locally to alter or cleave surfaces. The operation is generally under vacuum. Extruding Applying high pressures to a cast metal billet, forcing the metal to flow through a die orifice. Two types: direct and indirect. Heat treatment is often used after extrusion to attain the desired mechanical properties. Forging Deformation of metal, usually hot, with compressive force into desired shapes with or without dies. Five types: closed die, open die, rolled ring, impacting, and swaging. In each, pressure is exerted on dies or rolls, forcing the heated stock to take the desired shape. The first three are hot working, the other two are cold. Impact Deformation Applying impact force to a workpiece such that it is permanently deformed or shaped. Wastes containing metals and oils may result from cleaning the impacted parts. LASER Beam Machining Process whereby a highly focused monochromatic collimated beam of light is used to remove material at the point of impingement on a workpiece. Laser beam machining is a thermoelectric process with material removal largely accomplished by evaporation, although some material is removed in the liquid state at high velocity. Plasma Arc Machining Removal of material from shaping of a workpiece by a high velocity jet of high temperature ionized gas. A gas (e.g., nitrogen, argon, or hydrogen) is passed through an electric arc causing it to become ionized and raised to temperatures in excess of 16,649 °C (300,000 °F). The relatively narrow plasma jet melts and displaces the workpiece material in its path. Applying force (at a slower rate than at impact force) to permanently deform shape a workpiece. Cleanup wastes may contain metals and oils. Pressure Deformation 11 ------- Table 3. Types of Metal Shaping Operations (continued) Process Rolling Sand Blasting Thermal Cutting Ultrasonic Machining Description Reducing cross-sectional area of metal stock, or otherwise shaping metal products, through the application of pressure by rotating rolls. Cylindrical rolls produce flat shapes; grooved rolls produce rounds, squares, and structural shapes. Employs hot or cold working techniques depending on the kind of metal or alloy. Hot rolling is generally rolling at temperatures above the recrystallization temperature. Cold rolling is defined as rolling below the recrystallization temperature of the metal. Heat treatment is usually required before and between stages of the rolling process. Annealing is typically required between passes or after cold rolling to keep the metal ductile and remove the effects of work hardening. Removing stock, including surface films, from a workpiece by the use of abrasive grains pneumatically impinged against the workpiece. Waste blasting media can contain metals and residues from the surface of the metal. Cutting, slotting or piercing a workpiece using an oxyacetylene oxygen lance or electric arc cutting tool. Water may be used for rinsing or cooling of parts and equipment following this operation. Mechanical process designed to effectively machine hard, brittle materials. It removes material by the use of abrasive grains which are carried in a liquid between the tool and the work, and which bombard the work surface a high velocity and are agitated using high energy ultrasonic waves. Wastes Generated Each of the metal shaping processes can result in wastes that may contain chemicals of concern (depending on the metal being used). In general, there are two categories of waste generated in metal shaping operations: scrap metal and metalworking fluids/oils. Scrap metal may consist of metal removed from the original piece as well as amounts of metalworking fluids used prior to and during the metal shaping operation that generates the scrap. Metalworking fluids are applied to either the tool or the metal being tooled to facilitate the shaping operation (3). The metalworking fluid is used to: keep tool temperature down and aid lubrication; keep the workpiece temperature down and aid lubrication; provide a good finish; wash away chips and metal debris; and inhibit corrosion or surface oxidation. These metalworking fluids typically become spoiled or contaminated with extended use and reuse. In general, metal working fluids can be petroleum- based, oil-water emulsions, and synthetic emulsions (4). When disposed, these oils, often handled as hazardous, may contain levels of contaminants of concern including metals (cadmium, chromium, and lead) depending on the metal being tooled. Many fluids may contain chemical additives such as chlorine, sulfur and phosphorus compounds, phenols, cresols, and alkalies. In the past, such oils have been commonly mixed with used cleaning solvents and fluids (including chlorinated solvents). General Source Reduction and Recycling Techniques As described above, metal forming results in two types of waste: scrap metal and spent metalworking fluids. The most common management of these materials is either disposal or recycling. Facilities 12 ------- commonly recycle scrap metals that have value and defined recycling markets. Metals without significant value or without a defined recycling market, or metals that are not recyclable are commonly disposed. Table 4 provides examples of source reduction and recycling options that might be applied to various metal shaping operations. Contaminated and spoiled metalworking fluids are the largest source of waste from machining operations (3). Water- and animal fat-based oils can spoil without proper management and storage. All fluids can become contaminated with metals, packing and lubricating oils, and cleaning materials (including chlorinated solvents). The life of metalworking fluids can be increased (thus decreasing waste) through the source reduction and recycling techniques described in Table 4. This table provides examples of source reduction and recycling alternatives that are discussed further in documents referenced in Section VI. Table 4. Examples of Source Reduction and Recycling Options for Metal Shaping Operations Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information* Production Planning and Sequencing Improve scheduling of processes that require use of varying oil types in order to reduce the number of cleanouts. Process or Equipment Modification Standardize the oil types used for machining, turning, lathing, etc. This reduces the number of equipment cleanouts, and the amount of leftovers and mixed wastes. Use specific pipes and lines for each set of metals or processes that require a specific oil in order to reduce the amount of cleanouts. Save on coolant costs by extending machine coolant life through the use of a centrifuge and the addition of biocides Waste Savings/Reductions: 25 % reduction in plant-wide waste coolant generation. Product/Waste Throughput Information: based on handling 20,600 gallons of coolant per year. [Reference Install a second high speed centrifuge on a system already operating with a single centrifuge to improve recovery efficiency even more. Capital Investment: $126,000. Payback Period: 3.1 years. Product/Waste Throughput Information: based on handling 20,6000 gallons of coolant per year. [Reference #82] Install a chip wringer to recover excess coolant on aluminum chips. Capital Investment: $233,500. Payback Period: 0.9 years. Product/Waste Throughput Information: based on handling 20,600 gallons of coolant per year. [Reference #82] 13 ------- Table 4. Examples of Source Reduction and Recycling Options for Metal Shaping Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information* Process or equipment modification (continued) Capital Investment: $11,000 to $23,000 (chip wringer and centrifuge system). [Reference #81] Install a coolant recovery system and collection vehicle for machines not on a central coolant sump. Capital Investment: $104,000. Payback Period: 1.9 years. Product/Waste Throughput Information: based on handling 20,600 gallons of coolant per year. [Reference #82] **Use a coolant analyzer to allow better. control of coolant quality. Capital Investment: $5,000. Payback Period: 0.7 years. Product/Waste Throughput Information: based on handling 20,600 gallons of coolant per year. [Reference #82] Use an ultrafiltration system to remove soluble oils from wastewater streams. Annual Savings: $200,000 (in disposal costs). Product/Waste Throughput Information: based on a wastewater flow rate of 860 to 1,800 gallons per day. [Reference #81] Use disk or belt skimmers to remove way oil from machine coolants and prolong coolant life. Also, design sumps for ease of cleaning. Waste Savings/Reduction: coolant is now disposed once per year rather than 3-6 times per year. [Reference #6] Raw Material Substitution In cold forming or other processes where oil is used only as a lubricant, substitute a hot lime bath or borax soap for oil. **Use a stamping lubricant that can remain on the piece until the annealing process, where it is burned off. This eliminates the need for hazardous degreasing solvents and alkali cleaners. Annual Savings: $12,000 (results from reduced disposal, raw material, and labor costs). Waste Throughput Information: The amount of waste solvents and cleaners was reduced from 30,000 Ibs. in 1982 to 13,000 Ibs. in 1986. Employee working conditions were also improved by removing vapors associated with the old cleaners. [Reference #7] Waste Segregation and Separation If filtration or reclamation of oil is required before reuse, segregate the used oils in order to prevent mixing wastes. "Segregation of metal dust or scrap by type often increases the value of metal for resale (e.g., sell previously disposed metallic dust to a zinc smelter). Capital Investment: $0. Annual Savings: $130,000. Payback Period: immediate. Waste Savings/ Reduction: 2,700 tons per year. (Savings will vary with metal type and market conditions.) [Reference #19] 14 ------- Table 4. Examples of Source Reduction and Recycling Options for Metal Shaping Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information* Waste Segregation and Separation (continued) "Improve housekeeping techniques and segregate waste streams (e.g., use care when cleaning cutting equipment to prevent the mixture of cutting oil and cleaning solvent). Capital Investment: SO. Annual Savings: S3,000 in disposal costs. Waste Savings/Reduction: 60% (30 tons reduced to 10 tons). [Reference #81] Recycling Where possible, recycle oil from cutting/ machining operations. Often oils need no treatment before recycling. Capital Investment: $1,900,000. Annual Savings: $156,000. Waste Throughput Information: 2 million gallons per year. Facility reclaims oil and metal from process water. [Reference #19] Oil scrap mixtures can be centrifuged to recover the bulk of the oil for reuse. Follow-up magnetic and paper filtration of cutting fluids with ultrafiltration. By so doing, a much krger percentage of cutting fluids can be reused. Capital Investment: $42,000 (1976). Annual Savings: $33,800 (1980). [Reference #81] Perform on-site purification of hydraulic oils using commercial "off-the-shelf cartridge filter systems. Capital Investment: $28,000. Annual Savings: $17,800/year based on operating costs, avoided new oil purchase, and lost resale revenues. Payback Period: less than 2 years. Product/Waste Throughput Information: example facility handles 12,300 gallons/year of waste hydraulic oil. [Reference #82] **Use a continuous flow treatment system to regenerate and reuse aluminum chemical milling solutions. Capital Investment: $465,000. Annual Savings: $342,000. Payback Period: less than 2 years. Waste Savings/ Reduction: 90%. [Reference #81] **Use a settling tank (to remove solids) and a coalescing unit (to remove tramp oils) to recover metal-working fluids. Annual Savings: $26,800 (resulting from reduced material, labor, and disposal costs). [Reference #20] *The cost, savings, and waste reduction information provided in Table 4 is based on actual case studies and reflects the successes of actual metal fabricated products manufacturing facilities. Because specific applications are highly variable, however, you should use this information only as a indicator of how a particular pollution prevention option may perform under your circumstances. **These options cost less than $30,000 to implement. 15 ------- SECTION IV: SURFACE PREPARATION OPERATIONS Surface Preparation Processes Surface preparation is an integral step in the metal fabricated products manufacturing industry and is typically used in all metal fabricated products manufacturing processes. Virtually all fabricated metal products require some form of physical and/or chemical surface preparation prior to finishing to remove unwanted surface materials or to alter the chemical or physical characteristics of the surface. Some surface preparation operations also may be desired prior to some shaping operations. As a result of the initial and intermediate shaping processes, the metal surfaces usually have become oxidized or coated with grease and machining oils that may interfere with the finishing processes. Some products may require only the removal of rough surfaces and/or edges. There are a number of surface preparation methods that are used depending on the nature of the surface requirements. The major surface preparation methods include those listed in Table 5 (2). More detailed descriptions of these operations can be found in standard engineering references as well as many of the pollution prevention references described in the reference list included in this document. Table 5. Types of Surface Preparation Operations Process Solvent Cleaning: Emulsified Solvent Degreasing Ultrasonic Vapor Degreasing Vapor Degreasing Wiping Paint Stripping Chemical Treatment: Acid Cleaning Description Organic solvents are used to remove lubricants (oils and greases) and paints applied to the surface of metals during mechanical forming operations. Methods for degreasing include (5): Cleaning where the solvent and contaminants are suspended in water. The piece is either sprayed with or immersed in the emulsified solvent. Cleaning of parts using high energy sound waves and a solvent immersion bath. Cleaning of small parts by exposure to solvent vapors. Vapors are generated by heating a solvent reservoir. The surface is cleaned by the flushing action of solvent that condenses on the part. Different types of vapor degreasing include: immersion-vapor degreasing and spray-vapor degreasing. Manual cleaning of metal objects that are too large for immersion operations. Removal of organic coatings (paint) from a workpiece. The stripping of such coatings is usually performed with caustic, acid, solvent, or molten salt using processes similar to those for degreasing operations. Treatment performed as an integral part of forming processes to alter the surface of the metal. Operations include: Removing oxides and minor corrosion from metal surfaces. Acid cleaners are used in spraying, wiping, and electrolytic processes. 16 ------- Table 5. Types of Surface Preparation Operations (continued) Process Description Alkaline Cleaning Removing soils, grease, oil, and casting materials from forged, heat-treated and machined metal parts. Alkaline cleaners can be used in immersion, spray, and ultrasonic systems (described above). In addition, alkaline cleaners are compatible with steam and electrocleaning processes. Steam processes rely upon water vapor as the cleaning medium for the alkaline detergent. In electrocleaning, the metal part acts as the anode in an alkaline bath. Water is decomposed with hydrogen forming on the surface of the metal part. Hydrogen formation bubbles surface contaminants off of the metal part. Etching Corroding the metal surface as a means to remove surface contaminants. Etching can also be used to develop a design or pattern on the metal. Etching includes: bright dipping and chemical polishing which relies upon mixtures of acids to remove surface contaminants and/or corrosion; and chemical milling and etching whereby designs are created on the surface by controlled immersion in etching solutions. Pickling Another form of acid or alkaline cleaning operation, relying on a high concentration (5 to 25 percent) acid or alkaline solution to remove heavy scale and rust. Nitric, sulfuric, hydrochloric, and chromic acids are commonly used in pickling operations. Mechanical Surface Treatment: Altering the surface of formed metals using processes that include machining, grinding, polishing, tumbling (barrel finishing), and burnishing. Mechanical shaping operations are similar to metal parts shaping operations (see Section 3) in principle but are used to only change the nature or texture of the surface (not the gross form) of the object. These operations are used to change or prepare the surface of the object for additional shaping or plating. These types of operations result in various types of waste, as described below. Wastes Generated Surface preparation operations primarily generate wastes contaminated with solvents and/or metals depending on the type of cleaning operation. Specifically, concentrated solvent-bearing wastes and releases may arise, in general, from degreasing operations. Degreasing operations may result in solvent-bearing wastewaters, air emissions, and solid-phase wastes. That is, solvents may. be rinsed into wash waters and/or spilled into floor drains. Air emissions may result through volatilization during storage, fugitive losses during use, and direct ventilation of fumes. Any solid wastes (e.g.. wastewater treatment sludges, still bottoms, cleaning tank residues, machining fluid residues, etc.) generated by the operation may be contaminated with solvents. Chemical treatment operations can result in wastes that contain the metals of concern. Alkaline, acid, mechanical, and abrasive cleaning methods can generate waste streams such as spent cleaning media, wastewaters, and rinse waters. Such wastes consist primarily of the metal complexes or particles, the cleaning compound, contaminants from the metal surface, and water. In many cases, chemical treatment operations are used in conjunction with organic solvent cleaning systems. As such, many of these wastes may be cross-contaminated with solvents. The nature of the waste will depend upon the specific cleaning application and metal fabricated products manufacturing operation. Wastes from surface preparation operations may 17 ------- contribute to commingled waste streams such as - wastewaters discharged to centralized treatment. Further, such operations can result in direct releases such as fugitive emissions and easily segregated wastes such as cleaning tank residues. General Source Reduction and Recycling Techniques Surface preparation processes can result in various types of wastes depending on the specific nature of the manufacturing process. In many cases, alternative cleaning operations may be available that rely on less- or non-toxic cleaning agents. In cases where no alternative exists, source reduction and recycling may be used to extend solvent life and/or reduce solvent emissions. In general, identification of these opportunities relies upon the systematic identification of: methods to reduce solvent usage - solvents can be lost through volatilization. Further, improper or careless management of solvents can require premature contamination and replacement. opportunities to eliminate specific cleaning steps - that is, by controlling factors that contribute to surface contamination, the need for cleaning can be reduced or eliminated. less hazardous cleaning media - in most cases, there are several cleaning solvent systems that may perform the desired operation. In such cases, the solvent that poses the least risk to human health and the environment should be considered. methods to maximize cleaning efficiency - for cleaning operations that cannot be eliminated, the amount of cleaning material used to achieve the desired cleanliness should be minimized. procedures to segregate cleaning wastes - for cleaning wastes, segregation is an important part of proper management. Specifically, segregation is needed to allow and promote recycling of solvent-based cleaners. Further, segregation will help to reduce the amounts of toxic components from cleaning solvents that eventually collect in metal manufacturing wastes (e.g.. wastewater treatment sludges, used machining fluids, etc.). opportunities to reuse cleaning solvents - many cleaning materials can be recycled or reused. Reuse can be increased through procedures to reduce losses. Recycling operations can be increased through improved capture of chemicals released during the cleaning operation. opportunities to recycle cleaning solvents - once cleaning solvents are segregated, on- site and off-site recycling can be used to reduce waste and raw material consumption. Table 6 provides examples of source reduction and recycling techniques applicable to surface preparation operations. Table 6 provides a small sample of source reduction and recycling alternatives that are contained in the references identified in Section VI. Facilities that want additional information should access the PPIC directly. Further, facilities that would like to share their pollution prevention successes are encouraged to submit their information directly to the PPIC. 18 ------- Table 6. Examples of Source Reduction and Recycling Options for Surface Preparation Operations Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information'" SOLVENT CLEANING Training and Supervision Production Planning and Sequencing "Improve solvent management by requiring employees to obtain solvent through their shop foreman. Also, reuse "waste" solvents from cleaner up-stream operations in down-stream, machine shop- type processes. Pre-cleaning will extend the life of the aqueous or vapor degreasing solvent (wipe, squeeze, or blow part with air, shot, etc.). Use counter-current solvent cleaning (i.e., rinse initially in previously used solvent and progress to new, clean solvent). Cold clean with a recycled mineral spirits stream to remove the bulk of oil before final vapor degreasing. Only degrease parts that must be cleaned. Do not routinely degrease all parts. Capital Investment: $0. Annual Savings: $7,200. Waste Savings/Reduction: 49% (310 tons reduced to 152 tons). Product/Waste Throughput Information: original waste stream history: reactive anions (6,100 gallons/yr), waste oils (1,250 gallons/yr), halogenated solvents (500 gallons/yr). [Reference #23] Annual Savings: $40,000. Payback Period: 2 years. Waste Savings/Reduction: 48,000 gallons of aqueous waste. Aluminum shot was used to preclean parts. [Reference #19] 19 ------- Table 6. Examples of Source Reduction and Recycling Options for Surface Preparation Operations (continued) Pollution Prevention Techniques Process or Equipment Modification Process or Equipment Modification (continued) Raw Material Substitution Pollution Prevention Options The loss of solvent to the atmosphere from vapor degreasing equipment can be reduced by: increasing the free board height above the vapor level to 100% of tank width; covering the degreasing unit (automatic covers are available); installing refrigerator coils (or additional coils) above the vapor zone; rotating parts before removal from the vapor degreaser to allow all condensed solvent to return to degreasing unit; controlling the speed at which parts are removed (10 ft/min or less is desirable) so as not to disturb the vapor line; installing thermostatic heating controls on solvent tanks; and adding in-line filters to prevent paniculate buildup in the degreaser. **Reduce grease accumulation by adding automatic oilers to avoid excess oil applications. Use plastic blast media for paint stripping rather than conventional solvent stripping techniques. Use less hazardous degreasing agents such as petroleum solvents or alkali washes. For example, replace halogenated solvents (e.g., trichloroethylene) with liquid alkali cleaning compounds. (Note that compatibility of aqueous cleaners with wastewater treatment systems should be ensured.) Examples of Costs and Savings, and Other Information'*' Waste Savings/Reduction: volume of waste sludge is reduced by as much as 99% over chemical solvents; wastewater fees are eliminated. [Reference #81] Capital Investment: $0. Annual Savings: $12,000. Payback Period: immediate. Waste Savings/ Reduction: 30% of 1,1,1- trichloroethane replaced with an aqueous cleaner. [Reference #7] Capital Investment: $438,000. Payback Period: S.I years. Replaced trichloroethylene degreaser with aqueous cleaner system. [Reference #26] 20 ------- Table 6. Examples of Source Reduction and Recycling Options for Surface Preparation Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information* Raw Material Substitution (continued) Annual Savings: $2,000. Payback Period: 1.6 years. Substituted chlorofluorocarbon solvents with proprietary cleaner. [Reference #81] Annual Savings: 38% of cost savings and a 62% return on investment. Payback Period: 1.6 years. Substituted chlorofluorocarbon solvents with proprietary cleaner. [Reference #81] "Substitute chromic acid cleaner with non-fuming cleaners such as sulfuric acid and hydrogen peroxide. Annual Savings: $10,000 in treatment equipment costs and 52.50/lb. of chromium in treatment chemical costs. Product/Waste Throughput Information: rinse water flowrate of 2 gallons per minute. [Reference #81] Substitute non-polluting cleaners such as trisodium phosphate or ammonia for cyanide cleaners. Annual Savings: $12,000 in equipment costs and $3.00/lb. of cyanide in treatment chemical costs. Product/Waste Throughput Information: rinse water flowrate of 2 gallons per minute. [Reference #81] Recycling **Recycle spent degreasing solvents on site using batch stills. Capital Investment: $7,500. Annual Savings: $90,000. Payback Period: 1 month. Waste Savings/Reduction: 10,000 gallons annually of spent solvents by in- house distillation. [Reference #19] Recycle spent degreasing solvents on site using batch stills. Capital Investment: $2,600-$4,100 and $4,200-$17,000. Product Throughput Information: 35-60 gallons per hour and 0.6-20 gallons per hour, respectively. Two cost and throughput estimates for distillation units from two vendors. [Reference #81] Use simple batch distillation to extend the life of 1,1,1-trichloroethane (1,1,1- TCA). Capital Investment: $3,500 (1978). Annual Savings: $50,400. Product/Waste Throughput Information: facility handles 40,450 gallons 1,1,1-TCA per year. [Reference #82] When on-site recycling is not possible, agreements can be made with supply companies to remove old solvents. Capital Investment: $3,250 for a temporary storage building. Annual Savings: $8,260. Payback Period: less than 6 months. Waste Savings/Reduction: 38,000 pounds per year of solvent sent off site for recycling. [Reference #19] 21 ------- Table 6. Examples of Source Reduction and Recycling Options for Surface Preparation Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information"* Recycling (continued) Arrange a cooperative agreement with other small companies to centrally recycle solvent. CHEMICAL TREATMENT Process or Equipment Modification Increase the number of rinses after each process bath and keep the rinsing counter- current in order to reduce dragout losses. Unmixed acids in the wastewaters may-be recovered by evaporation. Reduce rinse contamination via dragout by: slowing and smoothing removal of parts, rotating them if necessary; using surfactants and other wetting agents; maximizing drip time; using drainage boards to direct dripping solutions back to process tanks; installing dragout recovery tanks to capture dripping solutions; using a fog spray rinsing technique above process tanks; using techniques such as air knives or squeegees to wipe bath solutions off of the part; and changing bath temperature or concentrations to reduce the solution surface tension. Process or Equipment Modification Instead of pickling brass parts in nitric acid, place them in a vibrating apparatus with abrasive glass marbles or steel balls. A slightly acid additive is used with the glass marbles, and a slightly basic additive is used with the steel balls. Capital Investment: $62,300 (1979); 50% less than conventional nitric acid pickling. [Reference #81] *Use mechanical scraping instead of acid solution to remove oxides of titanium. Annual Savings: $0; cost of mechanical stripping equals cost of chemical disposal. Waste Savings/Reduction: 100%. Waste Throughput Information: previously disposed 15 tons/year of acid with metals. [Reference #81] 22 ------- Table 6. Examples of Source Reduction and Recycling .Options for Surface Preparation Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information"1 Process or Equipment Modification (continued) **For cleaning nickel and titanium alloy, replace alkaline etching bath with a mechanical abrasive system that uses a silk and carbide pad and pressure to clean or "brighten" the metal. Capital Investment: $3,250. Annual Savings: $7,500. Waste Savings/Reduction: 100%. Waste Throughput Information: previous etching bath waste total was 12,000 gallons/year. [Reference #81] Clean copper sheeting mechanically with a rotating brush machine that scrubs with pumice, instead of cleaning with ammonium pcrsulfate, phosphoric acid, or sulfuric acid (may generate non-hazardous waste sludge). Capital Investment: $59,000. Annual Savings: more than $15,000. Payback Period: 3 years. Waste Savings/ Reduction: 40,000 pounds of copper etching waste reduced to zero. [Reference Annual Savings: $15,000 in raw materials, disposal, and labor. Payback Period: 3 years. Waste Savings/Reduction: avoids generation of 40,000 pounds per year of hazardous waste liquid. [Reference #81] Reduce molybdenum concentration in wastewaters by using a reverse osmosis/precipitation system. Capital Investment: $320,000. Waste Throughput Information: permeate capacity of 18,000 gallons per day. Savings Relative to an Evaporative System: installed capital cost savings: $510,000; annual operating cost savings: $90,000. [Reference #81] **When refining precious metals, reduce the acid/metals waste stream by maximizing reaction time in the gold and silver extraction process. Capital Investment: $0. Annual Savings: $9,000. Waste Savings/ Reduction: 70% (waste total reduced from 50 tons to 15 tons). [Reference #81] Raw Material Substitution Change copper bright-dipping process from a cyanide and chromic acid dip to a sulfuric acid/hydrogen peroxide dip. The new bath is less toxic and copper can be recovered. "Use alcohol instead of sulfuric acid to pickle copper wire. One ton of wire requires 4 liters of alcohol solution, versus 2 kilograms of sulfuric acid. Capital Investment: $0. [Reference #81] Replace caustic wire cleaner with a biodegradable detergent. Replace chromated desmutting solutions with nonchromated solutions for alkaline etch cleaning of wrought aluminum. Annual Savings: $44,541. Waste Savings/Reduction: sludge disposal costs reduced by 50%. [Reference #81] 23 ------- Table 6. Examples of Source Reduction and Recycling Options for Surface Preparation Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information1" Replace barium and cyanide salt heat treating with a carbonate/chloride carbon mixture, or with furnace heat treating. Replace thermal treatment of metals with condensation of saturated chlorite vapors on the surface to be heated. Waste Savings/Reduction: this process is fast, nonoxidizing, and uniform; pickling is no longer necessary. [Reference #81] Recycling Sell waste pickling acids as feedstock for fertilizer manufacture or neutralization/precipitation. Recover metals from solutions for resale. Annual Savings: $22,000. Payback Period: 14 months. Company sells copper recovered from a bright-dip bath regeneration process employing ion exchange and electrolytic recovery. [Reference #19] **Send used copper pickling baths to a continuous electrolysis process for regeneration and copper recovery. Capital Investment: $28,500 (1977). Product Throughput Information: pickling 12,000 tons of copper; copper recovery is at the rate of 200 g/ton of processed copper. [Reference #81] **Recover copper from brass bright dipping solutions using a commercially available ion exchange system. Annual Savings: $17,047; based on labor savings, copper sulfate elimination, sludge reduction, copper metal savings, and bright dip chemicals savings. Product Throughput Information: example facility processes approximately 225,000 pounds of brass per month. [Reference #81] **Treat industrial wastewater high in soluble iron and heavy metals by chemical precipitation. Annual Savings: $28,000; based on reduced water and sewer rates. Waste Throughput Information: wastewater flow from facility's "patening" line is 100 gallons per minute. [Reference #81] Oil quench baths may be recycled on site by filtering out the metals. Alkali wash life can be extended by skimming off the oil layer (this skimmed oil may be reclaimed). "The cost, savings, ana waste reduction information provided in Tab e 4 is based on actual case studies and reflects the successes of actual metal fabricated products manufacturing facilities. Because specific applications are highly variable, however, you should use this information only as a indicator of how a particular pollution prevention option may perform under your circumstances. ""These options cost less than $30,000 to implement. 24 ------- SECTION V: SURFACE FINISHING OPERATIONS Surface Finishing Processes Surface finishing may include one or a combination of methods and materials. Specifically, surface finishing may include a combination of five metal deposition operations and 21 finishing operations (80). The finishing operations consist of procedures used to assemble or complete the item. In many cases, surface preparation methods are included with these additional operations because they are often an integral portion of the finishing process. Table 7 describes types of surface finishing operations. More detailed descriptions of these operations can be found in standard engineering references as well as many of the pollution prevention references described in the reference list included in this document. EPA has also provided some general information on the types of wastes commonly associated with these processes. For many processes, however, EPA does not have descriptive or quantitative information concerning process wastes. Table 7. Types of Surface Finishing Operations Process Description METAL DEPOSITION OPERATIONS: Anodizing An electrochemical process which converts the metal surface to a coating of an insoluble oxide. Aluminum is the most frequently anodized material. The formation of the oxide occurs when the parts are made anodic in dilute sulfuric or chromic acid solutions. The oxide layer begins formation at the extreme outer surface and as the reaction proceeds, the oxide layer penetrates further into the metal surface. Conversion Coating Any operation that includes chromating, phosphating, metal coloring and passivating. In chromating, a portion of the basis metal is converted to a component of the protective film formed by the coating solutions containing hexavalent chromium and active organic or inorganic compounds. Phosphate coatings are formed by the immersion of steel, iron, or zinc plated steel in a dilute solution of phosphoric acid plus other reagents to condition the surfaces for further processing. Metal coloring involves the chemical method of converting the metal surface into an oxide or similar metallic compound to produce a decorative finish. Passivating is the process of forming a protective film on metals by immersion into an acid solution, usually nitric acid or nitric acid with sodium dichromate. Electroless Plating The chemical deposition of a metal coating on a workpiece by immersion in an appropriate plating solution in which electricity is not involved. Copper and nickel electroless plating for printed circuit boards are the most common operations. Immersion plating, considered a type of electroless plating, produces a metal deposit by chemical displacement. 25 ------- Table 7. Types of Surface Finishing Operations (continued) Process Electroplating Etching and Chemical Milling Description The production of a thin surface coating of one metal upon another by electrodeposition. Ferrous or nonferrous materials may be coated by a variety of common (copper, nickel, lead, chromium, brass, bronze, zinc, tin, cadmium, iron, aluminum or combinations thereof) or precious (gold, silver, platinum, osmium, indium, palladium, rhodium, indium, ruthenium, or combinations thereof) metals. In electroplating, metal ions supplied by the dissolution of metal from anodes are reduced onto the workplaces (cathodes). Depending on the metals involved, electroplating cells use acidic, alkaline, or neutral solutions. Operations used to produce specific design configurations or surface appearances on parts by controlled dissolution with chemical reagents or etchants. Chemical etching is the same process as chemical milling except the rates and depths of metal removal are usually much greater in chemical milling. FINISHING OPERATIONS: Assembly Brazing Burnishing Calibration Electroplating Electrostatic Painting The fitting together of previously manufactured parts or components into a complete machine, unit of a machine, or structure. The joining of metals by flowing a thin, capillary thickness layer of nonferrous filler metal into the space between them. Bonding results from the intimate contact produced by the dissolution of a small amount of basis metal in the molten filler metal, without fusion of the basis metal. The term "brazing" is used where the temperature exceeds 425 °F (800 °F). This operation is commonly followed by quenching, cooling or annealing in a solution of water or emulsified oils. The finish sizing or smooth finishing of a workpiece (previously machined or ground) by displacement, rather than removal, of minute surface irregularities. Wastes may come from spills, leaks, process solution dumps and post- finish rinsing and could contribute to the common metals, precious metals, and oily waste types depending upon the basis material finished. In addition, sodium cyanide (NaCN) may be used as a wetting agent and rust inhibitor (for steel), thus contributing cyanide wastes from this operation. Adjustment of the workpiece to dimensions needed to function as designed and within appropriate tolerances. Coating a workpiece by either making it anodic or cathodic in a bath that is generally an aqueous emulsion of the coating material. Electropainting is used primarily for primer coats because it gives a fairly thick, highly uniform, corrosion resistant coating in relatively little time. Ultrafiltration is used in connection with electropainting to concentrate paint solids. Wastewaters from these unit operations can result in wastes containing metals (including hexavalent chromium) and solvents. Application of electrostatically charged paint particles to an oppositely charged workpiece followed by thermal fusing of the paint particles to form a cohesive paint film. 26 ------- Table 7. Types of Surface finishing Operations (continued) Process Description Flame Spraying Application of metallic coating to a workpiece using finely powdered fragments of wire, together with suitable fluxes, which are projected through a cone of flame onto the workpiece. This operation is followed by quenching, cooling or annealing in a solution of water or emulsified oils. Wastes produced can contain metals and oil. Heat Treating Modification of the physical properties of a workpiece through the application of controlled heating and cooling cycles. Wastewater is generated through rinses, bath discharges, spills, and leaks, and often contain the solution constituents as well as various scales, oxides, and oils. Hot Dip Coating Coating a metallic workpiece with another metal to provide a protective film by immersion in a molten bath. Galvanizing (hot dip zinc) is the most common hot dip coating. Water is used for rinses following precleaning and sometimes for quenching after coating. These wastewaters can contain metals. Laminating Adhesive bonding layers of metal, plastic, or wood to form a part. Water is not often used in this operation; however, occasional rinsing or cooling may occur in conjunction with laminating. The wastes generated from these processes may include solvents and metals. Mechanical Plating Deposition of metal coatings on a workpiece via the use of a tumbling barrel, metal powder, and usually glass beads for the impaction media. The operation is subject to the same cleaning and rinsing operations that are applied before and after the electroplating operation. Painting Application of an organic coating to a workpiece. Painting processes result in solvent waste, paint sludge wastes, paint-bearing wastewaters and paint solvent emissions. Polishing Abrading operation used to remove or smooth out surface defects (scratches, pits, tool marks, etc.) that adversely affect the appearance or function of a part. Area cleaning and washdown can produce metal-bearing wastewaters. Sintering Forming a mechanical part from a powdered metal by fusing the particles together under pressure and heat. The temperature is maintained below the melting point of the basis metal. Soldering Joining metals by flowing a thin (capillary thickness) layer of nonferrous filler metal into the space between them. Bonding results from the intimate contact produced by the dissolution of a small amount of basis metal in the molten filler metal, without fusion of the basis metal. The term soldering is used where the temperature range falls below 425 °C (800 °F). This operation is followed by quenching, cooling or annealing in a solution of water or emulsified oils. Sputtering Covering a metallic or non-metallic workpiece with thin films of metal. The surface to be coated is bombarded with positive ions in a gas discharge tube, which is evacuated to a low pressure. 27 ------- Table 7. Types of Surface Finishing Operations (continued) Process Thermal Infusion Tumbling (Barrel Finishing) Vacuum Metalizing Vapor Plating Welding Description Applying fused zinc, cadmium, or other metal coating to a ferrous workpiece by imbuing the surface of the workpiece with metal powder or dust in the presence of heat. Controlled removal of burrs, scale, flash, and oxides as well as to improve surface finish. Barrel finishing produces a uniformity of surface finish not possible by hand finishing and is generally the most economical method of cleaning and surface conditioning. Wastewater is generated by rinsing of parts following the finishing operation and by periodic dumping of process solutions. Wastewaters may contain metals (including hexavalent chromium), cyanide, and oily waste depending upon the chemical solutions employed. ... Coating workpieces with metal by flash heating metal vapor in a high-vacuum chamber containing the workpiece. The vapor condenses on all exposed surfaces. Decomposition of a metal or compound upon a heated surface by reduction or decomposition of a volatile compound at a temperature below the melting point of either the deposit or the base material. Joining two or more pieces of material by applying heat, pressure or both, with or without filler material, to produce a localized union through fusion or recrystallization across the interface. This operation is followed by quenching, cooling or annealing in a solution of water or emulsified oils. Welding wastes may contain metals. Wastes Generated In general, surface finishing and related washing operations account for the largest volumes of wastes associated with these processes. These wastes fall into two groups: plating-related wastes and painting wastes. Specifically, metal plating and related processes account for the largest volumes of metal (e.g.. cadmium, chromium, lead, mercury, and nickel) and cyanide-bearing wastes. Painting operations account for the generation of solvent- bearing and direct release of solvents (including benzene, MEK, MIBK, toluene, and xylene). Paint cleanup operations may contribute to the release of chlorinated solvents (including carbon tetrachloride, methylene chloride, 1,1,1-trichloroethane, and perchloroethylene). The nature of the wastes produced by these processes is discussed next. Metal Deposition Operation Wastes Electroplating operations can result in solid and liquid wastestreams that contain the chemicals of concern. Liquid wastes result from workpiece rinsing and process cleanup waters. In general, most surface finishing (and many surface preparation) operations contribute to liquid wastestreams. Centralized wastewater treatment systems are common to this industry and can result in solid-phase wastewater treatment sludges. In addition to these wastes, spent process solutions and quench bathes are discarded periodically when the concentrations of contaminants inhibit proper function of the solution or bath. When discarded, process bathes usually consist of solid- and liquid- phase wastes that may contain high concentrations of the constituents of concern, especially cyanide (free and complexed). 28 ------- Related operations, including all non- painting processes, can contribute wastes including scrap metals, cleaning wastewaters, and other solid materials. The nature of these wastes will depend on the specific process, the nature of the workplace, and the composition of materials used in the process. However, due to the potentially diverse nature of these wastes, the remainder of this discussion focuses primarily on the plating operations which are similar among all metal fabricated products manufacturing industries. Finishing Wastes Painting operations result in emissions to the atmosphere as well as the generation of solid and liquid wastes. Atmospheric emissions consist primarily of the organic solvents used as carriers for the paint. Emissions result from paint storage, mixing, application, and drying. In addition, clean- up processes can result in the release of organic solvents used to clean equipment and painting areas. In many cases, chlorinated solvents are used in clean-up operations. Solid and liquid wastes can be generated throughout the painting operation. Sources of solid- and liquid-phase wastes include: paint application emissions control devices (e.g.. paint booth collection systems, ventilation filters, etc.), equipment washing, disposal materials used to contain paint overspray (e.g.. paper, cloth, etc.), and excess paints discarded upon completion of a painting operation or after expiration of the paint shelf-life. These solid and liquid wastes may contain metals from paint pigments and organic solvents such as paint solvents and cleaning solvents). General Source Reduction and Recycling Techniques As described above, surface finishing operations can result in two types of waste: plating and related operations, and painting operation wastes. Source reduction and recycling techniques for each of these materials are described below (81). Metal Deposition Operations Plating wastewaters are composed primarily of metallic species in aqueous solution. Plating sludges are generated from the treatment of wastewater and consist of complexed metal precipitants and water. In general, the key to reducing plating wastes includes: reuse of metal-bearing materials prior to discharge to centralized wastewater treatment, and/or segregation, reclamation, and recycling of metals from metal-bearing materials in place of discharge to centralized wastewater treatment. Various strategies and techniques for reusing metal- bearing materials have been developed and implemented by metal fabricated products manufacturing facilities. Examples of source reduction and recycling techniques are listed in Table 8. Other, non-painting, finishing operations such as polishing and sintering also can result in waste metals that might provide similar source reduction and recycling opportunities. These operations are similar to those discussed in previous sections. This discussion focuses primarily on source reduction and recycling techniques that have been applied to plating processes. Additional information on source reduction and recycling techniques for these operations can be found in documents identified in the reference list provided in this document. There are many strategies for reducing the generation and/or release of solvents and paint 29 ------- residues to the environment. Several examples are presented in Table 9. Both Tables 8 and 9 provide a small sample of source reduction and recycling alternatives that are discussed further in the references identified in Section VI. Facilities that want additional information should access the PPIC directly. Further, facilities that would like to share their pollution prevention successes are encouraged to submit their information directly to the PPIC. Table 8. Examples of Source Reduction and Recycling Options for Plating Operations Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information1" METAL DEPOSITION OPERATIONS Training and Supervision Educate plating shop personnel in the conservation of water during processing and in material segregation. Production Planning and Sequencing Preinspect parts to prevent processing of obvious rejects. Process or Equipment Modification Employ countercurrent rinsing to greatly reduce rinse water usage. Increase drain time to allow parts to drain 10 seconds or more after removal from bath. Add wetting agents to the plating baths to reduce adhesion of solution to the parts. Increase bath temperature to reduce viscosity and improve drainage. Use spray rinsing to increase rinsing efficiency for non-complex part configurations. Use air agitation in rinse tanks to improve rinsing efficiency. Change continuous treatment to a batch system to account for upsets in effluent levels. Capital Investment: $210,000. Payback Period: 3 years. Waste Savings/Reduction: reduced water usage from 12,000 gallons per day to 500 gallons per day. [Reference #19] Reduce bath evaporation by covering the surface with a blanket of polypropylene balls. 30 ------- Table 8. Examples of Source Reduction and Recycling Options for Plating Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information1" Continuously filter process baths to extend their life. If etching is done only to put a shine on the parts, some customers may agree to buy them unetched, thus, greatly reducing etch bath wastes. "Use low concentration plating solutions- rather than mid-point concentrations in order to reduce the total mass of chemicals being dragged out. Annual Savings: $1,300. Product/Waste Throughput Information: a nickel operation having 5 nickel tanks and an annual nickel dragout of about 2,500 gallons. [Reference Use the Kushner and Providence methods of double dragout followed by treatment or recycle of the concentrated dragout solution to minimize rinse water use. Annual Savings: using the Providence method in lieu of conventional water treatment: Shop size (gpd): 6,000, 36,000, and 184,000; Annual Savings: $17,110, $60,080, $44,095. [Reference Employ countercurrent and conductivity controls to reduce rinse water flows. Annual Operating Costs: $10.00/1,000 gallons. Annual Savings: $170,000. Waste Savings/Reduction: rinse water was reduced from 43,000 gallons per day to 8,000 gallons per day. [Reference #81] **Use electrolytic cells to recover metals from waste plating solutions. Applicable to recovery of gold, silver, cobalt, nickel, cadmium, copper, and zinc from solutions with 100 mg/1 to 1,000 mg/1 of metal. Capital Investment: $8,750 - $17,500. Metal Recovery: 1-2 tons/yr. Waste Savings/Reduction: metal losses reduced by a factor of 100. [Reference #81] 31 ------- Table 8. Examples of Source Reduction and Recycling Options for Plating Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information* Raw Material Substitution Use less toxic materials whenever possible. Substitute zinc for cadmium in alkali/saline environments. Substitute nitric or hydrochloric acid for cyanide in certain plating baths in order to eliminate cyanides in waste sludges= This substitution however, may not apply to all systems and may decrease the efficiency of certain waste water treatment systems. Substitute zinc chloride for zinc cyanide. Substitute a non-chlorinated stripper in place of methylene chloride. Waste Segregation and Separation Wastewaters containing recoverable metals should be segregated from other wastewater streams. Recycling Instead of disposing of plating bath when strength has decreased, filter and reconstitute it. Instead of disposing of process baths, attempt to make them marketable for resale. Annual Savings: $16,300. [Reference #81] Recycle used rinse waters into bath makeup solutions for their respective process baths. Reduce the quantity and toxicity of waste- waters by employing technologies such as: evaporation; Annual Savings: greater than $100,000. Payback Period: less than 1 year. Waste Savings/Reduction: from about 8,000 pounds of chromium consumed per month to less than 200 pounds per month. Company used a closed-loop evaporator on the chromium bearing rinse waters. [Reference #81] 32 ------- Table 8. Examples of Source Reduction and Recycling Options for Plating Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information* Recycling (continued) reverse osmosis; ion exchange; evaporation; Capital Investment: $12,200. Annual Operating Costs: $24,741. Annual Savings: $60,964. Payback Period: 7 months. Evaporative recovery employed on the company's nickel plating rinse waters. [Reference #7] Payback Period: 2-2.5 years. Waste Savings/Reduction: 84% reduction of chromium usage, 15-20% sludge reduction. Company installed an evaporative recovery unit for a chromium plating process. [Reference Capital Investment: $25,000, estimated for evaporative recovery equipment. [Reference #81] Installed Cost: $35,680. Annual Operating Cost: $9,160. Annual Savings: $21,000. System operates for 5,000 hours/year, recovering 9,375 Ibs/year chromic acid. [Reference 081] Capital Investment: $375,000. Payback Period: 2 years. Waste Savings/Reduction: 92% recovery of ion exchange-treated wastewater for reuse. [Reference #81] Payback Period: 5 years. Nickel sulfate solution is treated by ion exchange and returned to nickel plating process. [Reference #19] Capital Investment: $15,000 (1981). exchange unit installed to recover chromium. [Reference #81] Ion Capital Investment: $1.3 million. Annual Savings: $1.2 million. Product/Waste Throughput Information: 350,000 m'/year of wastewater. [Reference #57] 33 ------- Table 8. Examples of Source Reduction and Recycling Options for Plating Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information"' Recycling (continued) reverse osmosis; electrolysis; Capital Investment: $16,000. Payback Period: 20 months. Waste Savings/Reduction: almost 100% of lost chemical and 90% of wastewater recovered. Waste Throughput Information: 260 liters per hour of wastewater. [Reference #81] Capital Investment: $62,000 ($39,000 for the reverse osmosis unit). Payback Period: less than 2 years. Company installed reverse osmosis unit and evaporative heaters to recover nickel and rinse waters. [Reference #31] Capital Investment: $8,500. Waste Savings/Reduction: about 85% of the nickel dragout. Company installed reverse osmosis to recover nickel and rinse water. [Reference Capital Investment: $200,000 (330 ft2 membrane). Annual Operating Cost: large, due to high pressures in system. Publication discusses reverse osmosis in general and states that it is applicable to many electroplating baths. [Reference #81] Capital Investment: $21,500.. Operation Cost: $9,113. Gross Annual Savings: $17,464. Annual Savings: $8,351. Payback Period: 2.4 years. Product/Waste Throughput Information: economic information for a watts nickel plating line with dragout rates greater than one gallon per hour. [Reference #81] Capital Investment: $8,500. Annual Savings: $26,060 in chemical usage and process water. Product Throughput Information: 60,000 ft2 cadmium electroplating plant. Company implemented a high surface area (HSA) electrolytic reactor for cadmium recovery. [Reference #81] 34 ------- Table 8. Examples of Source Reduction and Recycling Options for Plating Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information* Recycling (continued) Capital Investment: $43,000 (1979). Annual Savings: treatment costs eliminated, between 5 and 14 kilograms each of silver, nickel, and copper are recovered weekly. Company used fluidized bed electrolysis to recover metals from electroplating rinse waters. [Reference #81] electrodialysis with ion exchange; and Capital Investment: $21,050 (15-cell-pair unit). Payback Period: 9 months. Company recovers gold from plating rinse water using electrodialysis and ion exchange. [Reference Capital Investment: $109,600 (1980). Annual Savings: $26,000/year (reduction in detoxification costs). [Reference #87] Capital Investment: $220,000. Annual Savings: $45,000. A medium sized jewelry plating and manufacturing company; updating the existing water treatment facility would have cost $500,000. [Reference #81] cyanide destruction. Capital Investment: $20,000-$50,000 for hydrolysis process. Waste Savings/Reduction: can reduce cyanide from 50,000 mg/1 to less than 30 mg/1. Waste Throughput Information: 300 gallons per day. [Reference #81] cyanide destruction (continued) Capital Investment: $10,000-$50,000 for chlorine and hypochlorite processes. Waste Throughput Information: 200 gallons per day - 20 gallons per minute. [Reference #81] Capital Investment: $300,000 for ozone oxidation. Product/Waste Throughput Information: rinse tanks operated at a rate of 4 gallons per minute (reactive rinsing can eliminate 2 out of 3 plating line rinse tanks). [Reference #81] 35 ------- Table 8. Examples of Source Reduction and Recycling Options for Plating Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information"1 Recycling (continued) **Use reactive rinsing in nickel plating operations to reduce rinse water use, improve plating efficiency, and conserve process chemicals. Capital Investment: $250 for plumbing and installation. Product/Waste Throughput Information: rinse tanks operated at rate of 4 gallons per minute (reactive rinsing can eliminate 2 out of 3 plating line rinse tanks). [Reference #81] Recover phosphate from aluminum bright dipping operations by reacting rinse acid with soda alkalies to yield a trisodium phosphate solution. Filter the solution, cool it (so trisodium phosphate crystallizes out), and recycle the remaining mother liquor with further batches of rinse acid. "The cost, savings, and waste reduction information provided in Table 4 is based on actual case studies and reflects the successes of actual metal fabricated products manufacturing facilities. Because specific applications are highly variable, however, you should use this information only as a indicator of how a particular pollution prevention option may perform under your circumstances. ""These options cost less than $30,000 to implement. 36 ------- Table 9. Examples of Source Reduction and Recycling Options for Finishing Operations Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information"' FINISHING OPERATIONS Training and Supervision Production Planning and Sequencing Process or Equipment Modification Always use proper spraying techniques. Improved paint quality, work efficiency, and lower vapor emissions can be attained by formal training of operators. Avoid buying excess finishing material at one time, due to its short shelf-life. Use the correct spray gun for particular applications: conventional air spray gun for thin- film-build requirements; airless gun for heavy film application; and air assisted airless spray gun for a wide range of fluid output. Preinspect parts to prevent painting of obvious rejects. Ensure the spray gun air supply is free of water, oil, and dirt. Replace galvanizing processes requiring high temperature and flux with one that is low temperature and does not require flux. Investigate use of transfer methods that reduce material loss such as: dip and flow coating; electrostatic spraying; and electrodeposition. ** Change from conventional air spray to an electrostatic finishing system. Use solvent recovery or incineration to reduce the emissions of volatile organics from curing ovens. Capital Investment: $900,000. Annual Savings: 50% (as compared to conventional galvanizing). Product Throughput Information: 1 ,000 kg/h. [Reference #81] Annual Savings: $15,000. Payback Period: less than 2 years. [Reference #81] Annual Savings: $400,000. [Reference #81] 37 ------- Table 9. Examples of Source Reduction and Recycling Options for Finishing Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information1" Process or Equipment Modification (continued) Regenerate anodizing and alkaline silking baths with contemporary recuperation of aluminum salts. Annual Savings: $0.02/m2 of aluminum treated. Annual Savings: (including sale of the recovered dry aluminum sulfate) $0.05/m2. Waste Throughput Information: based on an example plant that previously disposed 180,000 liters of acid solution per year at $0.07/litre. [Reference #81] Raw Material Substitution Use alternative coatings for solvent based paints to reduce volatile organic materials use and emissions, such as: high solids coatings (this may require modifying the painting process; including high speed/high pressure equipment, a paint distribution system, and paint heaters); Waste Savings/Reduction: 30% net savings in applied costs per square foot. [Reference #32] Waste Savings/Reduction: 41 % reduction in VOC emissions. The VOC of the paint decreased from 5.5 Ib./gallon to 3 Ib./gallon. [Reference #81] water based coatings; and Waste Savings/Reduction: 87% drop in solvent emissions and decreased hazardous waste production. [Reference #81] powder coatings. Capital Investment: $1.5 million. Payback Period: 2 years. Example is for a large, wrought iron patio furniture company. [Reference #81] Waste Segregation and Separation Segregate non-hazardous paint solids from hazardous paint solvents and thinner. Recycling Do not dispose of extended shelf life items that do not meet your facility's specifications. They may be returned to the manufacturer, or sold or donated as a raw material. Recycle metal sludges through metal recovery vendors. 38 ------- Table 9. Examples of Source Reduction and Recycling Options for Finishing Operations (continued) Pollution Prevention Techniques Recycling (continued) Pollution Prevention Options Use activated carbon to recover solvent vapors, then recover the solvent from the carbon by steam stripping, and distill the resulting water/solvent mixture. Regenerate caustic soda etch solution for aluminum by using hydrolysis of sodium aluminate to liberate free sodium hydroxide and produce a dry, crystalline hydrate alumina byproduct. Examples of Costs and Savings, and Other Information* Capital Investment: $817,000 (1978). Waste Savings/Reduction: releases of solvent to the atmosphere were reduced from 700 kg/ton of solvent used to 20 kg/ton. [Reference #81] Capital Investment: $260,000. Annual Savings: $169,282; from reduce caustic soda use, income from the sale of the byproduct, and a reduction in the cost of solid waste disposal. Payback Period: 1.54 years. Product/Waste Throughput Information: anodizing operation for which the surface area is processed at a rate of 200 m2/hour. [Reference #81] METAL FINISHING AND PAINTING CLEANUP Production Planning and Sequencing Raw Material Substitution Loss Prevention and Housekeeping Reduce equipment cleaning by painting with lighter colors before darker ones. Reuse cleaning solvents for the same resin system by first allowing solids to settle out of solution. Flush equipment first with dirty solvent before final cleaning with virgin solvent. Use virgin solvents for final equipment cleaning, then as paint thinner. Use pressurized air mixed with a mist of solvent to clean equipment. **Replace water-based paint booth filters with dry filters. Dry filters will double paint booth life and allow more efficient treatment of wastewater. To prevent spray gun leakage, submerge only the front end (or fluid control) of the gun into the cleaning solvent. Waste Savings/Reduction: 98%; from 25,000 gallons of paint cleanup solvents to 400 gallons. Company uses cleanup solvents in formulation of subsequent batches. [Reference #31] Annual Savings: $1,500. Waste Savings/Reduction: 3,000 gallons/year. [Reference #81] 39 ------- Table 9. Examples of Source Reduction and Recycling Options for Finishing Operations (continued) Pollution Prevention Techniques Waste Segregation and Separation Recycling Pollution Prevention Options Solvent waste streams should be kept segregated and free from water contamination. Solvent recovery units can be used to recycle spent solvents generated in flushing operations. Install a recovery system for solvents contained in air emissions. Use batch distillation to recover isopropyl acetate generated during equipment cleanup. Use batch distillation to recover xylene from paint equipment cleanup. Use a small solvent recovery still to recover spent paint thinner from spray gun cleanups and excess paint batches. Install a methyl ethyl ketone solvent recovery system to recover and reuse waste solvents. Arrange an agreement with other small com- panies to jointly recycle cleaning wastes. Examples of Costs and Savings, and Other Information* Annual Savings:- $1,000: [Reference 031] Payback Period: 2 years. [Reference #31] Payback Period: 13 months. Annual Savings: $5,000. [Reference #31] Capital Investment: $6,000 for a 15 gallons capacity still. Annual Savings: $3,600 in new thinner savings; $5,400 in disposal savings. Payback Period: less than 1 year. Waste Savings/Reduction: 75% (745 gallons of thinner recovered from 1,003 gallons). Product/Waste Throughput Information: 1,500 gallons of spent thinner processed per year. [Reference #81] Annual Savings: $43 ,000/year; MEK recovery rate: 20 gallons/day,' reflecting a 90% reduction in waste. [Reference #81] 40 ------- Table 9. Examples of Source Reduction and Recycling Options for Finishing Operations (continued) Pollution Prevention Techniques Pollution Prevention Options Examples of Costs and Savings, and Other Information'1' FACILITY CLEANUP Loss Prevention and Housekeeping Improve housekeeping practices to reduce spillage of cleaning solvents. Install collection/drip pans under machinery and lubrication operations to recover oils. Use rags to their full oil absorbing capacity, and use a laundering system to clean oil-laden rags. "The cost, savings, and waste reduction information provided in Tab e 4 is based on actual case studies and reflects the successes of actual metal fabricated products manufacturing facilities. Because specific applications are highly variable, however, you should use this information only as a indicator of how a particular pollution prevention option may perform under your circumstances. **These options cost less than $30,000 to implement. 41 ------- SECTION VI: POLLUTION PREVENTION DOCUMENTS AND REFERENCES Compendiums and Guides Table 10 contains a listing of some key guides and compendiums on waste minimization, pollution prevention and recycling that may be of particular interest or use for metal fabricated products industries. In many instances, these documents may provide a firm with important information as it begins to explore pollution prevention options for its operations. Copies of documents with EPA document numbers may be obtained from EPA or the Pollution Prevention Information Clearinghouse (PPIC). Copies of documents with PIES numbers may be obtained through PPIC/PIES. Table 10. Recommended Compendiums and Guides Title Date Author & Reference Abstract 1. Guides to Pollution Prevention. The Fabricated Metal Products Industry 1990 USEPA, Office of Research and Development EPAy625/7-90/006 An overview of metal fabrication waste generating processes and strategies for waste reduction and recycling. The Guide describes integral processes of aerospace, electronic, defense, automotive, furniture, domestic appliance, and other manufacturing industries. For these industries, the Guide summarizes source reduction and recycling alternatives for oily wastes, surface treatment and plating residues, and painting operation wastes. 2. Waste Minimization in Metal Parts Cleaning 1989 USEPA, Office of Solid Waste and Emergency Response EPA/530-SW-89-049 A summary of source reduction opportunities associated with metal parts surface preparation operations. The review includes descriptions of source reduction options including solvent substitutes, mechanical devices, alternative cleaning systems, and recycling options. 42 ------- Table 10. Recommended Compendium and Guides (continued) Title Date Author & Reference Abstract 3. Meeting Hazardous Waste Requirements for Metal Finishers 1987 USEPA, Center for Environmental Research Information EPA/625/4-87/018 An overview of techniques and strategies for meeting waste regulations applicable to metal fabricated products manufacturing industries. The document summarizes the information presented in three seminars presented in 1986. The document includes discussions of source reduction and materials recycling options that might be used'to meet compliance standards. 4. Waste Audit Study - Metal Finishing Industry 1988 California Alternative Technology Section and USEPA PIES 0005-073-A Description of waste audit protocol for metal finishing operations. The protocol is based upon audits at three small- to medium-sized operations. The manual includes discussions of common processes, wastes, and applicable source reduction and recycling techniques. 5. Waste Audit Study - Printed Circuit Board Manufacturers 1987 California Alternative Technology Section and USEPA PIES #005-006 Summary of protocol developed to support printed circuit board manufacturers in identification of source reduction and recycling opportunities. The manual includes discussions of processes and wastes common to the industry as well as applicable source reduction and recycling techniques. The effort focuses primarily on techniques applicable to small- and medium-sized facilities but describes source reduction and recycling applications that might be used throughout the industry. 6. Case Studies from the Minnesota Technical Assistance Program and the Oregon Hazardous Waste Reduction Program 1989 State of Minnesota, State of Oregon, and USEPA Compendium of case studies that describe source reduction and recycling techniques that have been used in metal fabricated products industries in Minnesota and Oregon. Case studies provide technical and economic information on proven techniques and technologies. 43 ------- Table 10. Recommended Compendiums and Guides (continued) Title 7. Case Summaries of Waste Reduction by Industries in the Southeast 8. Source Reduction of Chlorinated Solvents - Electronic Products Manufacture and Solvent Cleaning 9. Waste Minimization Opportunity Assessments Manual 10. Waste Minimization and Pollution Prevention: Metal Finishing A Self Audit Manual Date 1989 1990 1988 September 1990 Author & Reference North Carolina Pollution Prevention Program PIES #112-003-A Metropolitan Water District of Southern California and the Environmental Defense Fund PIES 0609-008-A and PIES 0609-005-A USEPA, Office of Research and Development EPA/625/7-88/003 Connecticut Hazardous Waste Management Service State of Connecticut Abstract Compendium of case studies that describe source reduction and recycling techniques that have been used in metal fabricated products industries in the USEPA Region IV States (North Carolina, South Carolina, Tennessee, Alabama, Georgia, Kentucky, Mississippi, and Florida). Case studies provide technical and economic information on proven techniques and technologies. Two volumes of a twelve volume set that focus on methods to reduce wastes associated with processes that result in chlorinated solvent-bearing wastes. Each document provides process descriptions and specific source reduction alternatives for the industry of concern (electronic products manufacturing and solvent cleaning operations). A description of a procedure to identify waste reduction opportunities for industrial processes. While the manual is not specific to any particular industries, it is designed to provide a systematic assessment strategy to any industrial generator. A step by step procedure of how to perform a self audit of a metal finishing operation. Contains forms to collect and organize data and a list of good operating practices for electroplaters. 44 ------- Table 10. Recommended Compendiums and Guides (continued) Title Date Author & Reference Abstract 11. Hazardous Waste Minimization Manual for Small Quantity Generators in Pennsylvania 1989 Center for Hazardous Materials Research PIES #101-004 An overview of general waste reduction concepts as well as discussions of waste minimization strategies appropriate for small industries including metal fabricated products manufacturing operations. This document provides a detailed study on source reduction and recycling techniques as they apply to small metal fabricated products industries in the State of Pennsylvania. Additional Pollution Prevention References EPA has identified additional documents that discuss pollution prevention concepts, techniques and technologies as they apply to metal fabricated products manufacturing operations. These documents are contained in the PPIC/PIES repository (indicated by a PIES number). Documents may be available through the PPIC depending on copywrite status and the desires of the author and/or publisher. The following list of references is divided by manufacturing process types to provide the user with some ideas on the specific topic of the document. A document does not appear in more than one section, eventhough it may discuss more than one of the processes described below. MACHINING Metalworking fluids 12. J.T. Johnson, Cincinnati Milacron Products Division. "A Comprehensive Strategy for an Overall Program of Metal Working Fluid Management". Cincinnati, OH, 1985. PARTS CLEANING/DECREASING Surface Preparation 13. R. Schecter and G. Hunt, North Carolina Pollution Prevention Pays Program. "Case Summaries of Waste Reduction by Industries in the Southeast". Raleigh, NC. 1989. Page 40. (PIES #112-003-A) 45 ------- Solvent Usage 14. L. Traverse, Massachusetts Office of Safe Waste Management. "Creative Source Reduction Techniques". Third Annual Massachusetts Hazardous Waste Source Reduction Conference Proceedings. Boston, MA. October 23, 1986. (PIES #022-012) 15. R. Schecter and G. Hunt, North Carolina Pollution Prevention Pays Program. "Case Summaries of Waste Reduction by Industries in the Southeast". Raleigh, NC. 1989. Page 39. (PEES #112-003-A) 16. C. H. Fromm, S. Budaraju and S. A. Cordery, Jacobs Engineering Group. "Minimization of Process Cleaning Waste". Solvent Waste Reduction Alternatives Seminar. Speaker Papers. Washington, DC. March 1988. (PIES #005-012-A-000) 17. E. A. Rodzewich. "Source Reduction - Parts Cleaning". Solvent Waste Reduction Alternatives Seminar. Speaker Papers. March 1988. (PIES #005-012-A-000) 18. Jacobs Engineering Group, Inc. for USEPA, Hazardous Waste Engineering Research Laboratory, Office of Research and Development. Waste Minimization Audit Report: Case Studies of Solvent Wastes from Parts Cleaning and from Electronic Capacitor Manufacturing Operations. Cincinnati, OH. (PIES #010-003-A) 19. Institute for Local Self-Reliance. "Engine and Plumbing Parts Manufacture, Case Study 60", Proven Profits from Pollution Prevention: Case Studies in Resource Conservation and Waste Reduction, Volume II. Washington, D.C. 1989. (PIES #306-001-A) 20. North Carolina Department of Environment, Health, and Natural Resources: Pollution Prevention Program. Managing and Recycling Solvents in the Furniture Industry. Raleigh, NC. May 1986. (PIES #034-018-A) 21. Hackney, Pollution Prevention Challenge Grant Program, North Carolina Department of Natural Resources. "Pilot Study of Solvent Recovery for Use in Paint Equipment Cleanup". December 1986. (PIES #034-050-A-000) 22. N. H. Frick and G. W. Gruber, PPG Industries, Inc. Solvent Waste Minimization by the Coatings Industry. Pittsburgh, PA. March 1988. (PIES #800-01) 23. California Department of Health Services, Alternative Technology Section, Toxic Substances Control Division, Waste Audit Study: Automotive Paint Shops. January 1987. (PIES #005-005) 24. M. Drabkin and P. Sylvestri, USEPA Hazardous Waste Engineering Research Laboratory, Office of Research and Development. Waste Minimization Audit Report: Case Studies of Minimization of Solvent and Electroplating Wastes at a POD Installation. Cincinnati, OH. 1989. (PIES #101-036-8) Aqueous Cleaners 25. K. B. Patterson and D. E. Hunt, U.S. Air Force, AGMC/MAQSE, Newark Air Force Base, OH. "The Cyl-Sonic Cleaner: Aqueous Ultrafiltration Cleaning Using Biodegradable Detergents". Proc 46 ------- Technology '88: The Key to Hazardous Waste Minimization. Air Force Logistics Command. Sacramento, CA. August 15-18, 1988. (PIES #100-100-D) 26. T. Smietana, Office of Safe Waste Management "Trichloroethylene Elimination Case Study: Electric Furnace #2 Bright Anneal Line Industrial Metals Department of Texas Instruments, Inc.," , Third Annual Massachusetts Hazardous Waste Source Reduction Conference Proceedings. October 23, 1986. (PIES #022-012) Wastewaters 27. Massachusetts Department of Environmental Management, Office of Safe Waste Management. Preliminary Report: Phase I Source Reduction Activities. Southeast Platers Project. Case Study B. July, 1988. Page 3. (PIES # 022-003-A) 28. North Carolina Department of Natural Resources and Community Development. "Water Conservation for Electroplaters: Counter-Current Rinsing". Raleigh, NC. 1985. (PIES #034-024A) 29. North Carolina Department of Natural Resources and Community Development "Water Conservation for Electroplaters: Rinse Tank Design". Raleigh, NC. 1985. (PIES #034-026A) 30. Office of Safe Waste Management, Massachusetts Department of Environmental Management. "The Robbins Company: Wastewater Treatment and Recovery System, A Case Study." Raleigh, NC. 1985. (PIES #034-0268) Degreasing 31. G. Hunt, North Carolina Department of Natural Resources and Community Development. "Accomplishments of North Carolina Industries - Case Summaries". Raleigh, NC. January 1986, p. 22. (PIES #034-010) 32. Hazardous Waste Reduction Program of the Oregon Department of Environmental Quality. "The Tektonix Payoff". Salem, OR. June 1988. (038-003-A-OOO) 33. United Nations, Economic and Social Council, Economic Commission for Europe. "Compendium on Low-and Non-Waste Technology: Elimination of Chlorine by the Use of Fumeless In-line Degreasing in the Aluminum Industry". Geneva, Switzerland. 1983. (PIES #400-103) 34. New Jersey Hazardous Waste Facilities Siting Commission, Hazardous Waste Source Reduction and Recycling Task Force. A Study of Hazardous Waste Source Reduction and Recycling in Four Industry Groups in New Jersey. Newark, NJ. April 1987. Case study D4.1, p. 30. (PIES #031-001-A) 35. S. P. Evanoff, et. al. "Alternatives to Chlorinated Solvent Degreasing - Testing, Evaluation, and Process Design" Process Technology '88. Sacramento, CA. August 15-18, 1988. (PIES #100-100-D) 47 ------- SURFACE TREATMENT AND PLATING Electroplating 36. G. Hunt, et al., North Carolina Department of Natural Resources and Community Development. "Accomplishments of North Carolina Industries - Case Summaries". Raleigh, NC. January 1986, p. 22. (PIES #034-010) 37. United Nations, Economic and Social Council, Economic Commission for Europe'Compendium on Low- and Non-Waste Technology: A Low-Waste Electroplating Process". Geneva, Switzerland. 1985. (PIES #400-125) 38. D. Huisingh, L. Martin, H. Hilger, N. Seldman, The Institute for Self-Reliance. "Proven Profit from Pollution Prevention". Washington, D.C. 1985, case study 26, Page 103. (PIES #306-001-A) 39. G. F. McRae. "In-Process Waste Reduction: Part 1 - Enviroscope," Plating and Surface Finishing. June 1988. 40. David Wigglesworth, et.al., Alaska Health Project. "Waste Reduction Assistance Program (WRAP) On-Site Consultation Audit Report: Electroplating Shop". Anchorage, Alaska. April 7, 1987, pp. 17. (PIES #002-016-A-001) 41. Edward Saltzberg, Ph.D., Science Applications International Corporation. "Methods to Minimize Wastes From Electroplating Facilities", Process Technology '88: The Key to Hazardous Waste Minimization. Air Force Logistics Command. Sacramento, CA. August 15-18, 1988. (PIES #100- 100-D) 42. Hubbard Enterprises, San Diego County, Department of Health Services. "Minimizing Waste from an Electroplating Operation", Pollution Prevention, A Resource Book for Industry. San Diego, CA. 1990. (PIES #005-079-A-000) 43. Jerome Kohl, et. al., North Carolina State University, School of Engineering. "Reducing Hazardous Waste Generation with Examples from the Electroplating Industry". Raleigh, NC. 1986. 44. Office of Safe Waste Management, Massachusetts Department of Environmental Management. "Source Reduction Recommendations for Precious Metal Platers." Boston, MA. April 1988. (PIES #002-012) Electroplating - Chromium 45. D. Achman, Minnesota Technical Assistance Program. "Reducing Chromium Losses from a Chromium Plating Bath", Minnesota Technical Assistance Program Summer Intern Report. Summer 1987. (PIES #709-030) 46. United Nations Economic and Social Counsel. "Use of an Evaporator in Chromium Electroplating", Compendium on Low and Non-waste Technology. Monograph ENVAVp.2/5/Add.47. Geneva, Switzerland. 1988. (PIES #400-125) 48 ------- Electroplating - Cyanide-containing wastes 47. L. E. Vaaler, Office of Safe Waste Management. "Prospects for Developing Substitutes for Cyanide- Containing Electroplating Baths", Third Annual Massachusetts Hazardous Waste Source Reduction Conference Proceedings. Boston, MA. October 23, 1986. (PIES #022-012) 48. USEPA Research and Development, Risk Reduction Engineering Laboratory. "Waste Minimization Audit Report: Case Studies of Minimization of Cyanide Waste from Electroplating Operations", Project Summary. Cincinnati, OH. January 1988. (PIES #101-023-8) Electroplating - Nickel 49. Minnesota Technical Assistance Program. Metal Recovery: Metal Finishing Shop. Minneapolis, MN. September 1988. (PIES #709-017) SO. P. Pajunen, Eco-Tech Ltd., and E. Schneider, Hewlett Packard, American Electroplaters and Surface Finishing Society and U.S. EPA. "Copper and Nickel Removal in Printed Circuit Board Processing by Ion Exchange and Electroforming", Ninth AESF/EPA Conference on Environmental Control for the Metal Finishing Industry. January 25-29, 1988. 51. T. Nadeau, et. al.. "Copper, Nickel and Chrome Recovery in a Jobshop to Eliminate Waste Treatment and Sludge Disposal", Third Annual Massachusetts Hazardous Waste Source Reduction Conference Proceedings, Office of Safe Waste Management. Boston, MA. October 23, 1986. (PIES #022-012) 52. Minnesota Technical Assistance Program. Metal Recovery: Ion Exchange. Minneapolis, MN. September 1988. (PIES #709-019) 53. T. V. Tran, et al. "Recovery of Nickel Salts by Electrodialysis Reversal Process," Presented at 73rd Annual AESF Technical Conference and Exhibit of Surface Finishing. The American Electroplaters and Surface Finishers Society Bulletin: TP 334-ST. June 23, 1986. (PIES #222-00l-A-001) Electroplating - Cadmium 54. North Carolina Pollution Prevention Program. "Potential Recovery and Reuse of Cadmium from an Electroplating Bath". Pollution Prevention Challenge Grant Program. Raleigh, NC. December 1987. (PIES #034-050-A-000) Electroplating - Zinc 55. Hazardous Waste Reduction Program, Oregon Department of Environmental Quality. Guidelines for Waste Reduction and Recycling: Metal Finishing. Electroplating. Printed Circuit Board Manufacturing. Eugene, OR. July 1989. (PIES # 038-010) Electrowinning 56. Tom Nadeau, et. al. "Copper, Nickel and Chrome Recovery in a Jobshop to Eliminate Waste Treatment and Sludge Disposal", Third Annual Massachusetts Hazardous Waste Source Reduction 49 ------- Conference Proceedings, Office of Safe Waste Management. Boston, MA. October 23, 1986. (PIES #022-012) Continuous Hardening 57. United Nations, Economic and Social Council, Economic Commission for Europe. "Compendium on Low- and Non-Waste Technology: Continuous Hardening and Zinc-Coating". Geneva, Switzerland, 1981. (PIES #400-103) Zinc Coating 58. United Nations, Economic and Social Council, Economic Commission for Europe "Compendium on Low- and Non-Waste Technology: Continuous Hardening and Zinc-Coating". Geneva, Switzerland, 1981. (PIES #400-103) Brite Dip Baths 59. Institute for Local Self-Reliance. "Engine and Plumbing Parts Manufacture, Case Study 60", Proven Profits from Pollution Prevention: Case Studies in Resource Conservation and Waste Reduction, Volume II. Washington, DC. 1989. (PIES #306-001-A) 60. Minnesota Technical Assistance Program, University of Minnesota. "Metal Recovery: Etchant Substitution". Minneapolis, MN. 1989. (PIES # 709-014-A-OOO) 61. A. Boyce, Tekronix, Inc. and D. J. Kavanaugh, CH2M Hill Industrial Design Corporation. "Electrolytic Regeneration of Chromic/Sulfuric Acid Etchant," Ninth AESF/EPA Conference on Environmental Control for the Metal Finishing Industry. American Electroplaters and Surface Finishing Society and U.S. EPA, Washington, DC. January 25-29, 1988. 62. V. R. Sellers. "Waste Management Alternatives for Electroplating and Printed Circuit Board Manufacturing Operations", Third Annual Massachusetts Hazardous Waste Source Reduction Conference Proceedings, Office of Safe Waste Management. Boston, MA. October 23, 1986. (PIES #022-012) 63. Thaddeus Smietana. "Trichloroethylene Elimination Case Study: Electric Furnace #2 Bright Anneal Line Industrial Metals Department of Texas Instruments, Inc.", Third Annual Massachusetts Hazardous Waste Source Reduction Conference Proceedings, Office of Safe Waste Management. Boston, MA. October 23, 1986. (PIES #022-012) 50 ------- Chrome conversion 64. New Jersey Hazardous Waste Facilities Siting Commission, Hazardous Waste Source Reduction and Recycling Task Force. "A Study of Hazardous Waste Source Reduction and Recycling in Four Industry Groups in New Jersey", Case study D6.1, p.33. Newark, NJ. April 1987. (PIES #031-001- A) Painting 65. K. Weigel. "Developments in Powder Coating Technology", Metal Finishing. April 1989, pp. 41-44. 66. D. S. Tyler, Volstatic, Inc. "Electrostatic Powder Coating: Finishing for the Future", Metal Finishing. January 1985, pp. 23-26. 67. Hans Sutler, Umweltbundesamt. "Low-waste Technologies in-the Federal Republic of Germany", The Environmental Professional. Volume U, pp. 190-198. Berlin, Germany. 1989. (PIES #458-006-A- 001) 68. North Carolina Department of Environment, Health, and Natural Resources: Pollution Prevention Program. Managing and Recycling Solvents in the Furniture Industry. May 1986. (PIES #034-018-A) 69. Hazardous Waste Reduction Program of the Oregon Department of Environmental Quality. "The Tektonix Payoff. Salem, OR. June 1988. (PIES #038-003-A-000) 70. Mark Manzione, Brown and Caldwell Consulting Engineers. "Waste Minimization for Electroplating and Aircraft Paint-Stripping Wastewater Treatment", Process Technology '88: The Key to Hazardous Waste Minimization, Air Force Logistics Command. Sacramento, CA. August 15-18, 1988. (PIES #100-100-D) 71. Hackney, Pollution Prevention Challenge Grant Program, North Carolina Department of Natural Resources. "Pilot Study of Solvent Recovery for Use in Paint Equipment Cleanup". Raleigh, NC. December 1986. (PIES #034-050-A-000) 72. California Department of Health Services, Alternative Technology Section, Toxic Substances Control Division. Waste Audit Study: Automotive Paint Shops. Sacramento, CA. January 1987. (PIES #005- 005) 73. United States Environmental Protection Agency, Hazardous Waste Engineering Research Laboratory, Office of Research and Development Waste Minimization. Audit Report: Case Studies of Minimization of Solvent Waste from Parts Cleaning and from Electronic Capacitor Manufacturing Operations. Cincinnati, OH. November 1987. (PIES #101-008-A). 51 ------- SECTION VH: BIBLIOGRAPHY In addition to the documents identified in Section VI, the following documents were used to develop this report. 74. Office of Management and Budget. "Handbook of Standard Industrial Classifications." Springfield, VA. 1987. 75. United States Environmental Protection Agency, Office of Water. "Development Document for Effluent Limitations Guidelines and Standards for the Nonferrous Metals Forming and Metal Powders Point Source Category." Washington, DC. 1986. 76. United States Environmental Protection Agency, Office of Research and Development. "Guides to Pollution Prevention - The Fabricated Metal Products Industry." Washington, DC. 1990. (EPA/625/7-90/006) 77. Franklin Associates for the United States Environmental Protection Agency. "Composition and Management of Used Oil Generated in the United States." Mission, KS. 1984. 78. United States Environmental Protection Agency, Office of Solid Waste. "Industrial Resource Recovery Practices: Fabricated Metals Production, Machinery Manufacturing/Non-Electrical, and Manufacturing of Electrical Machinery." McLean, VA. 1982. 79. United States Environmental Protection Agency, Office of Solid Waste. "Waste Minimization in Metal Parts Cleaning." Washington, DC. 1989. (PIES #101-056-A) 80. United States Environmental Protection Agency. "Development Document for Effluent Limitations Guidelines and Standards for the Metal Finishing Point Source Category. Washington, DC. 1983. 81. United States Environmental Protection Agency, Office of Solid Waste. "Pollution Prevention in Metal Manufacturing - Saving Money Through Pollution Prevention (DRAFT)." Washington, DC. 1989. (PIES #101-054-A) 52 ------- APPENDIX A ------- Releases of the 17 Chemicals of Concern By Metal Manufacturing Industries (in pounds) SIC 34 Chemical Benzene Cadmium CC1< CH2C12 CHC13 Chromium Cyanide Lead MEK Mercury MIBK Nickel TCE PCE Toluene Xylene 111 TCE Land + Injection 0 106000 0 0 0 1100789 27250 110378 168310 0 0 22066 4 26965 34517 31234 32898 Air 132 4750 0 3682720 0 104280 78742 98624 7783053 0 2221038 108118 10971337 3864849 9141163 16247570 12086091 Water 0 278 0 262 0 7160 4353 2898 500 0 0 16046 1388 10 67 276 535 Other Transfers 250 631430 0 558261 0- 3550057 813464 1458406 3192717 0 593975 2444351 1397660 652884 1775865 2187671 1676409 Total 382 636458 0 4241243 0 4762268 923809 1670306 11144580 0 2815013 2590581 12370389 4544708 10951612 18466751 13795933 ------- Releases of the 17 Chemicals of Concern By Metal Manufacturing Industries (in pounds) cont. SIC 35 Chemical Benzene Cadmium CC14 CH2C12 CHC13 Chromium Cyanide Lead MEK Mercury MIBK Nickel TCE PCE Toluene Xylene 111 TCE Land + Injection 0 1 0 0 0 543 0 32007 250 0 0 785 1100 0 0 27624 0 Air 62317 3300 0 1753930 0 36976 2000 16642 2342567 0 353834 24096 5979064 1681180 4084061 7065077 6585150 Water 0 1 0 0 0 2296 1 80 6 0 161 501 2730 0 250 40 40597 Other Transfers 500 638 0 314892 0 2907984 6083 54627 519165 0 36545 932448 345792 98021 497932 537092 752644 Total 62817 3939 0 2068822 0 5855783 8084 103356 2861988 0 390540 957830 6328686 1779201 4582243 7629833 7378391 ------- Releases of the 17 Chemicals of Concern By Metal Manufacturing Industries (in pounds) cont. SIC 36 Chemical Benzene Cadmium CC14 CH2C12 CHC13 Chromium Cyanide Lead MEK Mercury MIBK Nickel TCE PCE Toluene Xylene 111 TCE Land + Injection 0 8800 0 250 0 837 0 282000 2 250 0 11013 734 0 2 12442 7737 Air 0 1159 0 10858010 2150 59600 7289 195711 14633707 1681 519978 14511 6017921 3760992 9848899 13362826 13178506 Water 0 284 0 1433 0 351 1250 0379 250 1 1 1988 1537 282 1519 1534 1261 Other Transfers 0 203943 0 1907897 0 376356 40993 3355740 1300256 59510 59252 1063540 789576 879625 990906 1550351 2060735 Total 0 205386 0 1276790 2150 437144 49532 3839830 15934215 61442 11252 1091052 1393639 38240899 10841326 1547530303 15248239 ------- Releases of the 17 Chemicals of Concern By Metal Manufacturing Industries (in pounds) cont. SIC 37 Chemical Benzene Cadmium CC1< CH2C12 CHC13 Chromium Cyanide Lead MEK Mercury MIBK Nickel TCE PCE Toluene Xylene 111 TCE Land + Injection 0 250 0 1739 0 55490 0 24632 60905 0 0 40750 250 27000 39942 0 5950 Air 360529 1351 0 8237059 26910 54571 2065 113919 13510807 0 4912197 77388 6072105 7727503 16411671 37960496 17617966 Water 263 125 0 623 5 4523 132 1508 1429 0 0 2316 3 1634 750 250 16922 Other Transfers 13463 45223 0 602430 1709 2899431 119924 1535438 3881378 0 895230 655590 702710 399602 2847173 4507721 995896 Total 374255 46699 0 8841851 28624 3014015 122121 1675497 17454519 0 5808427 776044 6775068 8155739 19299536 42468467 18636734 ------- |