An Analysis of Pollution Prevention Opportunities and Impediments in the Fabricated Metal Products Manufacturing Sector in Georgia, 9/96 Prepared by: Mike Garruto, Pollution Prevention Engineer

Introduction

The purpose of this report is to identify the specific causes of waste generation, and cost-effective solutions that will reduce waste in the fabricated metal products industry in Georgia. The benefits of reducing waste can be reduced pollution and decreased operating costs to the business. Releases of high-priority toxic chemicals are the primary focus of this report, but other significant solid and liquid wastes will be included. Often, barriers exist that limit the implementation of pollution prevention projects and technologies. Barriers and strategies to overcome them will also be discussed in this report.

Methodology

A survey of metal fabricators in Georgia was undertaken in 1995 to complement existing literature on pollution prevention in this industry. To expedite completion of the survey questionnaire, the transportation equipment industry, SIC 37, and the fabricated metal products industry were combined. A review of trade journals and environmental publications had indicated that many of the wastes generated in these two sectors were from common processes, particularly surface preparation, cleaning, and finishing processes. Within each of these sectors, not all SIC codes were surveyed. Only those meeting the following requirements were chosen:

• Sectors that produce significant hazardous wastes based on TRI and biennial report data
• Sectors that have a significant number of manufacturers in Georgia
• In SIC 37, the airline equipment industry was eliminated based on P²AD’s previous in-depth exposure to this sector. Boat manufacturers were also removed from the survey population based on the variety of materials used in their processes.

The approach of reviewing the existing literature and databases and surveying Georgia manufacturers was chosen to identify the problems and solutions that are most significant in the State. In addition, the survey documented processes employed by Georgia fabricated metal products manufacturers, waste reduction activities, sources of waste reduction assistance, and barriers to pollution prevention encountered by these businesses. The survey, selection of manufacturers to participate in the survey, and survey results were prepared by Georgia State University, School of Urban Studies. A copy of the survey is located in Appendix I. 100 manufacturers were surveyed, or 9.8% of the 1016 Georgia manufacturers in these two categories. Follow-up phone conversations and plant visits were made to a small subset of manufacturers and Biennial Report Hazardous Waste Reduction Plans were reviewed to further refine the study. The results of the study are presented in this document.

Summary

The following key issues were identified as a result of this study through the survey, contacts with Georgia fabricated metal products manufacturers, review of biennial reports and TRI data, and review of various trade and environmental publications:

• Waste generation from coatings application
• Waste generation from surface preparation and cleaning activities
• Waste generation from metal forming operations
• Waste generation from plating operations
• Lack of in-house technical expertise

The Georgia Pollution Prevention Assistance Division (P²AD) will assist Georgia fabricated metal products manufacturers in addressing these key issues by developing programs, providing information resources, and assisting companies with technical issues. The approach that P²AD will take is to identify existing resources that address organizational, technical, and research needs. Georgia metal fabricators can benefit by developing pollution prevention programs, which can help lead to significant reductions in waste generation and costs. P²AD can assist manufacturers in developing these programs, providing information on up-to-date technologies, organizing demonstration projects showing the applicability of new technologies, and providing on-site technical assistance. In this manner, P²AD can help companies meet their organizational and technical needs in order to reduce waste while improving profitability.

Appendix IV provides background information on P²AD’s pollution prevention manufacturing sector assessments, including a listing of the industries studied.

Profile of Fabricated Metal Products Manufacturing Sector in Georgia

Standard Industrial Classification (SIC) 34, “Fabricated Metal Products, Except Machinery and Transportation Equipment,” consists of companies that fabricate ferrous and nonferrous metals including metal cans, tinware, hand tools, cutlery, general hardware, structural products, metal forgings, metal and wire products, among other items. Often, coatings are applied by these companies to improve the product’s appearance and corrosion protection. SIC’s 25, 35, 36, 37, 38, and 39 also contain establishments that fabricate metal products and the contents of this document may be relevant to many of these firms. The table below highlights the types of companies within SIC 34 only.

Table 1 – Georgia Fabricated Metal Products Manufacturers

There are a wide variety of products manufactured in this industry. However, many of the products are manufactured using similar processes. These processes will be reviewed within this report to interpret their waste generating characteristics.

The fabricated metal products sector employs over 28,000 employees in 848 plants. The plants range in size from 1 to 1,000 employees, with 33 employees being the mean. 80% of the companies have 50 employees or less, and even more significantly, 45% of the plants have a staff of 10 or less. Unlike most of the sector, metal cans and metal forgings plants tend to have larger staffs. The description below outlines the geographic clusters of metal fabrication shops and employees located in Georgia.

Metropolitan Atlanta, consisting of the 13 counties in the ozone non-attainment area, is home to 388 manufacturers claiming SIC 34 as their primary business and employing 12,007 people according to the 1994/1995 Georgia Manufacturing Directory. The largest concentration is in Cobb, DeKalb, Fulton, and Gwinnett counties where there are 285 metal fabricators and 8,343 employees. This means that one third of the metal fabrication shops in the state are located in four of Georgia’s counties.

North Georgia excluding the metropolitan Atlanta area, contains 177 fabricated metal products plants employing 6,211 personnel within a 50 county area. The strongest cluster of manufacturers in this area closely surrounds the metropolitan Atlanta area detailed above. Fourteen of the counties do not contain any metal fabricators.

Southeast Georgia fabricated metal products manufacturers number 127 in a 45 county area and employ 5,261. Half of these companies are located in Chatham, Emanuel, Richmond, Laurens, Glynn, and Bulloch counties. Seventeen of the counties contain no metal fabricators according to the Manufacturing Directory.

Southwest Georgia contains 156 companies in a 49 county area with a fabricated metal products work force of 4,752. Similarly, half of these companies are located in a few locales including Muscogee, Lowndes, Bibb, Troup, and Colquitt counties. 21 of the 49 counties do not contain any companies that claim metal fabrication as their primary business.

Fabricated Metal Products Industrial Processes

The fabricated metal products industry in Georgia consists of companies that form, forge, machine, weld, assemble, and finish coat ferrous and non-ferrous metals. The industry fabricates a wide variety of products including aluminum doors, armaments, piping, soft drink cans, heating equipment, ductwork, and a range of products too numerous to mention here. Table 2 lists the common processes that are responsible for the generation of toxic, hazardous, and non-hazardous wastes. The percentages represent the results from our survey of metal fabricators and transportation equipment suppliers. Ranges for company size were chosen in order to keep the populations of each category similar and add to the statistical significance of the data.

Table 2 – Georgia Fabricated Metal Manufacturers Processes

98% of the companies surveyed listed at least one of the above processes as part of their ongoing operations. 96% of the companies have some sort of metal shaping operation, while 49% do some form of surface preparation, 57% have a painting process, and only 14% have a plating or anodizing process. The most common processes reported are listed below:

• Assembly by 79%
• Welding by 74%
• Solvent-based painting by 47%
• Machining by 44%
• Forming by 40%
• Water-based painting by 31%

No surface preparation activities are among the top six processes used, but all the types of surface preparation listed are used by 14%-22% of the companies. It is likely that a large percentage of metal fabricators do not generate significant amounts of hazardous or toxic waste as their work is concentrated in metal shaping, as opposed to cleaning and finishing. These findings indicate that the non-regulated subset of companies may be more interested in solid waste reduction pollution prevention, while others should be concerned with solvent reduction or elimination in cleaning and finishing processes.

Notably, small companies are much less likely to have a painting operation or use the different surface preparation techniques. The smaller companies may be most concerned with solid waste minimization. Large companies over 60 employees have the most variety of processes as might be expected. These companies will have more pollution prevention opportunities and may also have more staff to deal with these issues. Education about pollution prevention may be helpful in getting them started in developing voluntary company-wide pollution prevention programs.

Companies that have to submit Toxic Release Inventory (TRI) reports and Biennial Large Quantity Generator (LQG) reports tend to be larger than those that do not report. As an example, the average size of the 1993 TRI reporter in SIC 34 was 148 employees. Approximately one-fourth of the employees in SIC 34 work for a TRI reporter, while these companies make up only 6% of the metal fabricators in the state. Based on the survey, there are many additional companies in Georgia that are not required to submit these regulatory reports, but do use painting and cleaning processes that are similar and therefore emit wastes similar to the larger TRI-reporting companies.

Waste Stream and Generation Characteristics of Georgia Fabricated Metal Products Manufacturers

The 1993 TRI and Hazardous Waste Large Quantity Generator (LQG) Biennial reports provide a snapshot of the chemical releases and waste generation in the industry. This information is summarized in Table 3. Of the 848 companies listing fabricated metal products as their primary business, only a small percentage are required to submit TRI and LQG reports.

Table 3 – 1993 Reported TRI Emissions and LQG Hazardous Waste Generation for Georgia Metal Fabricators

Based on the data, the following observations are made:

• 4.6% of companies in SIC 34 are Large Quantity Generators of hazardous waste.
• 6.4% of metal fabricators submit TRI reports.
• One company is responsible for over 50% of the hazardous waste reported by LQG’s.
• The top five companies account for 90% of the hazardous waste reported by LQG’s.
• Metal plating operations tend to report high quantities due to their hazardous wastewater generation. This points out a limitation in using biennial reports in that the entire wastestream is counted, not just the hazardous portion, therefore, it is not easy to compare quantities or toxicity from one company to another using the biennial reports without going into more detail.

Toxic Releases

The specific “high priority” toxic chemicals released by the metal fabrication industry in Georgia as reported in the 1993 TRI are shown in Figure 3. A high priority chemical is one of the 17 chemicals identified in Phase 1 of this study. These chemicals are all TRI listed and exhibit carcinogenic or ozone-depleting characteristics, or were released to the environment in Georgia in large quantities. In particular, note that 1,1,1-trichloroethane, methyl ethyl ketone, methyl isobutyl ketone, toluene, trichloroethylene, and xylene tend to have high amounts of air emissions. These are all solvents which readily volatize when they are used as carriers for coatings or as degreasers. On the other hand, chromium, copper, lead, nickel, and zinc are used in plating and anodizing operations. The wastes from these operations are likely to be removed in the form of a solid or sludge and are typically sent to either a hazardous waste landfill or incinerator.

When the subsectors within SIC 34 are compared as in Figure 4, metal cans and shipping containers (3410’s), fabricated structural metal products (3440’s), metal forgings and stampings (3460’s), and coating, engraving, and allied services (3470’s) stand out in particular in terms of total environmental releases and transfers. After analysis of the data, P²AD has chosen to concentrate the study in two areas: fabricated structural metal products where only a small percentage of the 459 companies are TRI reporters; and coating, engraving, and allied services, where mandates have forced companies to comply with many air, water, and hazardous waste regulations. Within both these sectors, the companies in Georgia tend to be small with limited technical staff. In addition, these two sectors account for more than half of the metal fabrication plants in Georgia and approximately half the TRI and LQG reporters.

Solid Waste

Typical solid wastes generated by metal fabricators include the following:

• Steel scrap and other metals. This includes trim, out-of-specification product, and metal shavings. A substantial number of companies in Georgia are able to recycle at least a portion of these wastes.
• Wood packaging is another major source of solid waste. Pallets and other wood crating account for a majority of the wood waste. Besides disposal, options for these waste include reuse, rebuilding pallets and crates, fuel for boilers, or mulch.
• Cardboard, stretch wrap, styrofoam, and other packaging.
• Office wastes including paper, cardboard, food, beverage containers, construction materials.

Water

Water use varies widely in this sector. High usage is often found in the metal finishing sector (3470’s) due to rinsewater usage and plating baths. Typically, the metal finishers have a wastewater pretreatment plant on site. As an example, one mid-size plating shop in Georgia uses approximately 40 million gallons of water per year. Significant opportunities for water reduction exist at this plant and many others throughout the state.

Pollution Prevention in the Fabricated Metal Products Industry – Barriers, Sources of Assistance, and Waste Reduction Methods

The survey of Georgia fabricated metal products manufacturers collected data on common waste reduction methods, pollution prevention barriers, and sources of pollution prevention assistance. Table 4 reports barriers to pollution prevention identified by the survey. Table 5 lists the sources of assistance and information provided to companies about waste reduction. Table 6 provides a summary of the types of waste reduction efforts used by fabricated metal products manufacturers.

Pollution Prevention Barriers

Table 4 – Barriers to Pollution Prevention

• 64% of companies identified at least one barrier
• Small companies, those with less than 11 employees, claimed limited in-house expertise, technology limitations, and insufficient capital at a substantially higher rate than larger companies.

The high level of responses for “insufficient capital” and “not economically feasible” may indicate that companies still do not distinguish between the cost-effective benefits of pollution prevention reductions at the source and expensive treatment opportunities downstream of the process. Furthermore, a better understanding of the true costs of waste might change this outlook. Appendix III contains examples of impediments confronted by Georgia metal fabricators as stated in their biennial Hazardous Waste Reduction Plans.

Pollution Prevention Assistance

Table 5 – Sources of Pollution Prevention Assistance

• 40% of the companies surveyed received outside assistance
• Government, universities, and trade associations often supply their services at little or no charge, yet they are the least used forms of assistance
• Large companies with over 60 employees are twice as likely to use government assistance as mid-size companies (11-60 employees). None of the small companies polled received government assistance.
• Large companies were 3 to 6 times as likely as the smaller firms to use consultants, corporate management, vendors, and industry trade associations.
• Universities are the only group that seems to have made equal efforts in waste minimization outreach toward small, mid-size, and large companies.
• 78% of small companies, 71% of mid-size companies, and 30% of large companies surveyed have received no form of outside assistance in waste minimization.

There is quite a disparity between the amount of resources used by large companies and small companies. The large companies have more in-house expertise and use outside forms of assistance more frequently than the smaller companies. Potential reasons for this may include the following:

• more stable and substantial cash flow to hire consultants
• more man hours available to spend studying waste minimization opportunities
• large companies are more likely to be regulated already, and may have less hesitation in showing their plant to outsiders
• vendors may be more likely to call on and assist large companies, anticipating a better chance of substantial sales volume

Waste Reduction Methods

Table 6 – Methods of Waste Reduction

Over 90% of the firms surveyed stated they were have undertaken some form of waste minimization. The most popular methods were as follows:

• Recycling by 77%
• Inventory Control by 61%
• Energy Conservation by 53%

These often used solutions may be easier or more practical to implement. Also, the recycling numbers indicate that companies are farther along on the learning curve regarding recycling versus pollution prevention. It also demonstrates the high degree to which recycling markets for at least some materials are available to manufacturers in Georgia.

Large companies are approximately 2 to 3 times more likely than smaller firms to take advantage of the following waste minimization practices:

• Spill/leak prevention
• Process equipment changes
• Process optimization
• Alternative product design

From the data on waste reduction methods, pollution prevention assistance, and pollution prevention barriers, it appears that small companies have not been as active in reducing wastes and may be potential candidates for P²AD’s assistance services. However, it should also be noted that the small companies are less likely to be using solvent-based processes. Appendix II highlights successful pollution prevention by Georgia companies as outlined in their Biennial Hazardous Waste Reduction Plans.

Key Pollution Prevention Issues

The following key issues were identified during the fabricated metal products manufacturing sector study:

• Waste generation from coatings application
• Waste generation from surface preparation and cleaning activities
• Waste generation from metal shaping processes
• Waste generation from metal plating operations
• Lack of technical resources at facilities

Each of these issues will be examined in more detail in the following sections.

Waste Generation from Coatings Application

Industrial Users of Coatings

57% of the metal fabricators surveyed in Georgia have a painting process in their operations. Extrapolated, this would mean that over 500 companies in SIC 34 may have a painting operation. Companies visited use a wide range of coatings and application methods depending on the performance requirements, quantity, value, and shape of parts, and availability of finances to make capital improvements. In addition, a good understanding of the painting process and its effect on costs and the environment helps companies make sound business decisions. Paint spray guns are the most prevalent application system while solvent-based paints are still used more often than waterborne coatings.

Waste Generation

Wastes generated from the painting process include commonly used solvents released to the air during painting or as the coating dries. This is verified in the TRI statistics highlighted earlier in this report. Solvents are also used to clean the painting equipment, releasing further solvents to the air. Solvents used include xylene, toluene, methyl ethyl ketone, methyl isobutyl ketone, water, and mineral spirits. Additional waste is created in the spray booth, and is typically either made up of disposable filters or paint sludge depending on whether the plant has a dry booth or a waterwash booth.

Characteristics of Paint Application Processes

Liquid coatings are comprised of resins, pigments, solvents, and additives. These components determine the performance characteristics and appearance of the coating. Manufacturers in Georgia use both solvent-based and water-based coatings. It should be noted that “water-based” paints can contain up to 30% solvents in the mixture. However, the typical waterborne coating does contain less solvents. Acrylic, alkyd, epoxy, polyurethane, and vinyl resins can all be used with waterborne, conventional solvent-based, and high solids coatings.

Application processes range from manual application with a brush or manual spray application to sophisticated automated systems using rotary electrostatic spray guns or alternative materials like autophoretic coatings. The different systems will be described in the pollution prevention alternatives below.

Pollution Prevention Options – Painting Processes

Painting Spray Techniques

A good entry level pollution prevention initiative is to train paint spray gun operators to minimize overspray, maximize transfer efficiency, and therefore reduce waste and raw materials costs. Capital costs of these changes are non-existent and training costs should be minimal. Good spray techniques that reduce waste include the following:

• Aim the center of the spray pattern at the bottom of the preceding stroke.
• Move the spray gun parallel to the surface being coated.
• Trigger the spray gun only when pointed at the part.
• Train the operator to prevent pressures from getting too high.
• Maintain the gun nozzle the proper distance from the part.

Vendors, technical schools, or industry publications and training sessions can be utilized to learn the basics of good spray painting techniques. Automation of the process may also help meet the requirements listed above.

Pollution Prevention Spray Equipment Alternatives

Alternative spray equipment can range from the relatively inexpensive replacement of conventional spray guns with HVLP spray guns to the costly replacement of entire painting lines with powder coating, autophoretic coatings, or rotary electrostatic systems. Size of the plant, number, complexity, and value of parts to be cleaned, uniqueness of parts, upstream and downstream processes, transfer efficiency, regulations, and coating performance requirements all contribute to the feasibility of using alternative equipment in a coating system. The chart below lists the common spray technologies, their transfer efficiencies, and characteristics.

T.E. = transfer efficiency in %. Ranges are estimated based on several sources.

Paint usage can vary dramatically based on the transfer efficiency of the spray gun chosen. Often, a more expensive spray gun will have a quick payback period based on reduced paint costs. In the right situation, a company may also consider alternative application methods including dip coating, roll coating, and brush application. These non-spray technologies often have transfer efficiencies above 90% but may have limitations in their cost-effective usage.

Pollution Prevention Alternatives to High VOC Paints

As stated previously, organic surface coatings, or paints, consist of solvents, resins, pigments, extenders, and additives. The resins, or binders, provide the properties of the coatings and are often associated with the type of paint, i.e., epoxy, alkyd, vinyl, acrylic. Pigments provide color and some corrosion resistance properties. Extenders are similar to pigments while additives are used to control drying, flow, and wetting among other properties. Finally, solvents dissolve the paint materials to form a liquid mixture that can be sprayed. Once applied to the part, the solvent evaporates, leaving behind the paint film. Common paint solvents include xylene, toluene, MEK, N-butyl alcohol, and water. Many of these solvents are volatile organic compounds, or VOCs, which contribute to ozone creation (smog) when reacted with nitrogen oxides in the air. With all other factors constant, lower solvent content in paint will produce lower amounts of hazardous waste. Fortunately, there are many alternatives Georgia metal fabricators can choose from to replace a traditional high solvent paint. These include high-solids, 100%-solids, U/V curable coatings, carbon dioxide cosolvent coatings, waterborne coatings, autophoretic coatings, and powder coating.

High-solids coatings are similar in composition to conventional solvent-based coatings but contain about 50% to 95% solids, a significant increase compared to conventional coatings. In turn, VOC emissions are greatly reduced. The finish is comparable to solvent-based coatings. Paint spray equipment may have to be modified for this high viscosity fluid and it is possible that surface preparation may become more critical. High-solids coatings in conjunction with alternative spray equipment can dramatically reduce VOCs.

100%-solids coatings do not contain any solvents in their formulation. However, a small amount of VOCs may be emitted upon curing. Costs may be two or three times conventional solvent based painting, but much more actually ends up on the part instead of wasted as overspray. Dry film thickness requirements may also be lower with this option. Most of the traits of high solids coatings also hold for 100%-solids coatings.

Waterborne coatings use water as a major solvent but also include other solvents, or “cosolvents,” in quantities up to 30% of the weight of the product. They can be a good drop-in substitute for solvent-based paint, although some parameters may need to change. Potential changes include replacement of pumps and piping with stainless steel materials, grounding of electrostatic systems, and changes to throughput depending on drying times. These coatings are typically low in VOCs, have a comparable finish to solvent-based counterparts, have low odor, and can be a cost effective replacement.

Electrostatic powder coating lines have been installed by many Georgia manufacturers. Using this method, dry powder is metered into a compressed air driven spray gun. The spray gun ionizes the air and particles are charged. The part is given an opposite charge and the coating is electrostatically attracted to the surface. The powder contains no solvents and is often referred to as a “dry painting process.” Overspray can be easily collected and reused. This provides for very high efficiency. Electrostatic spray is used to provide a good initial transfer efficiency and with reuse, transfer efficiencies can approach 95% to 100%. The coating should be cured in conventional ovens.

U/V curable coatings, carbon dioxide cosolvent coatings, and autophoretic coatings are all proven technologies for coatings. However, these are more expensive than the other options and will typically be used only in certain applications including auto industry suppliers. For this reason, this paper will not attempt to summarize these “high-tech” coatings. Metal fabricators must keep in mind that there is no one perfect type of coating for any one application and the benefits and drawbacks of each must be considered in a thorough evaluation of alternatives.

Pollution Prevention in Painting by Production Planning

Planning within the production process is a good way to minimize wastes and save money. Metal fabricators should have an inventory control system in place that will prevent the proliferation of outdated materials. Also, wastes should be segregated to reduce the volume of hazardous waste produced. Plants should consider buying paints in bulk containers for often used colors and types to minimize the residuals. In a similar manner, plants should buy the smallest possible container where very little paint is needed. This will help prevent the eventual accumulation of hazardous wastes. A production supervisor can schedule painting of parts of the same color together so that equipment cleaning steps can be eliminated, reducing VOC emissions. These appear to be minor changes, but they can add up quickly towards a company being removed from LQG status.

Waste Generation from Cleaning and Surface Preparation

Industrial Users of Cleaning and Surface Preparation Methods

Approximately half of the metal fabricators in Georgia surveyed use at least one method of metal surface preparation. It is likely that most of these companies perform a painting or plating operation downstream of the surface preparation step. Larger companies are more likely to require a surface preparation step since many of the smaller companies concentrate on metal shaping and assembly without painting their product before shipping to the customer.

Common Characteristics

The surface preparation step is undertaken to remove unwanted surface materials, or to alter the chemical or physical characteristics of the metal. Parts may have been contaminated with machining oils, fingerprints, or grease that need to be removed before the part is coated. Surface preparation usually consists of one or a combination of the following methods:

• Solvent vapor degreasing
• Solvent baths
• Aqueous degreasers or baths
• Mechanical cleaning

Waste Generation

Solvent degreasing can generate air emissions, solvent-bearing wastewaters, and solid wastes. Aqueous degreasing operations can still have some solvent content and may also produce high pH wastes, oil wastes, or metal wastes that can exceed POTW limits. Chemical treatment operations result in wastes containing metals from the cleaned part and can produce high or low pH wastes. Water rinses are usually necessary after chemical treatment baths and this water usage varies widely in the industry. Mechanical cleaning generates spent media along with the metals. Air emissions shown in the TRI data for 1,1,1-trichloroethane, toluene, xylene, and trichloroethylene are caused at least in part by cleaning operations. It is important to note that a non-hazardous cleaner can become hazardous when it is mixed with the metal and contaminants being cleaned. A common sight in Georgia plants is a parts washer station. The wastes from these are often collected by the solvent supplier, or can be distilled on or off-site. However, companies in Georgia should be aware that they have a choice in equipment, chemicals, and suppliers.

Pollution Prevention Opportunities in Metals Surface Preparation and Cleaning

Solvent Cleaning Pollution Prevention

• Avoid the need to clean – When considering a change, companies are often most comfortable evaluating and implementing the least costly alternatives first. In minimizing solvent cleaning, companies should first ask themselves why the part is being cleaned. If upstream or downstream processes can be eliminated or altered to avoid the need to clean, companies should seriously consider these changes and the monetary and regulatory benefits. It may be necessary for the company to work with its supplier to achieve this change.
• Employee training – The plant should consider training employees in good operating practices when cleaning. The training should not only illustrate the “how-to” of good operating practices, but should also explain how these practices can save the company money and lessen environmental impacts. Example training topics could include keeping the lid on a solvent rag bin, the basic concepts of a two stage washer, and segregation of wastes. It is critical to get the important details down to an operational level in order to ensure success.
• Extend the life of the solvent – Small batch distillation units can be purchased inexpensively for batches as small as 3-5 gallons. These units will allow the solvent to be reused several times at an additional capital, operating, energy, and maintenance cost. However, this can be cost effective versus buying more virgin solvent and producing more hazardous wastes. A two stage counterflow wash comprising a dirty solvent followed by clean solvent can also significantly reduce solvent usage. In-line filters may also extend the life of the solvent at a minimal cost.
• Solvent alternatives – Aqueous washes, aqueous cleaners, ultrasonic cleaning, addition of agitation to bath, less toxic or hazardous solvents, mechanical brushing or blasting, and steam cleaning can all be considered as potential substitutes or modifications to an existing solvent degreaser or bath. For the long term, substituting a less or non-hazardous cleaner may be the company’s best choice. The SAGE (Solvent Alternatives Guide) expert system software, developed by Research Triangle Institute for EPA, is available through P²AD and can be a helpful starting point in evaluating alternatives. In evaluating surface preparation choices, companies should consider the contaminant, the substrate material, drying requirements, regulations, and cost. These factors should be weighed according to the company’s priorities. P²AD is available to assist in generating appropriate alternatives.

Aqueous Cleaning Pollution Prevention

Aqueous cleaners are mixtures of water, detergents, and other additives that promote the removal of organic and inorganic contaminants from hard surfaces. Equipment used includes ultrasonic cleaners, manual parts washers, automatic spray equipment, and baths with agitation. Heat is often used to speed up the cleaning process. Aqueous cleaners can be acidic, neutral, or alkaline depending on the substrate compatibility and the cleanliness required. Water effluent can be a concern with aqueous cleaners, particularly with pH, total oils/organics, and metals. Some aqueous parts washers stations are equipped with filters to remove contaminants and the water is evaporated or changed out infrequently to minimize generation of non-compliant wastes. Pilot testing of new cleaners and equipment is recommended before making a purchase or changing operating practices.

Mechanical Cleaning Pollution Prevention

Traditional mechanical cleaning methods include power-tool cleaning and blasting (often referred to as “sandblasting”). Sandblasting can use glass, sand, steel, aluminum, slag-based materials (Black Beauty), or plastic as a blasting media. Wastes generated may or may not be hazardous depending on the parts that are cleaned or stripped. Also, slag based products can be high in metals and can leach toxics at concentrations high enough for the waste to be classified as hazardous. Often, all blasting materials will have to be tested for toxicity. For this reason, a reduction in the amount going to the landfill will reduce testing costs in addition to disposal costs. These reductions will have to be weighed against potential increases in the price of alternative materials and equipment. When choosing a blasting media, it is important to consider how many times the material can be reused before disposal. For small jobs, power-tool cleaning may be considered as it will reduce waste amounts. Other potential technologies include cryogenic blasting and high pressure water blasting. Cryogenic blasting uses pelletized dry ice as the blasting medium which will not contribute to the waste stream. Capital costs will be high for this option. Finally, less waste may be produced if less stringent criteria can meet the finishing requirements, i.e., a commercial blast instead of near white metal blast.

Waste Generation from Metal Shaping Processes

Industrial Users of Metal Shaping Processes

Almost all Georgia metal fabricators perform some type or combination of metal shaping processes. In particular, assembly, welding, and machining are performed by a substantial number of small and large fabricators alike.

Common Characteristics

Metal shaping operations convert the raw materials to their intermediate or final form. Primary shaping typically converts the metal into a sheet, bar, or plate. Secondary shaping alters the metal into an intermediate or final form by stamping, turning, drilling, cutting, grinding, or other processes. Metalworking fluids are typically used to cool the part, aid lubrication, provide a good finish, wash away chips, and inhibit corrosion.

Waste Generation

In general, two types of wastes are generated in the metal shaping processes. These wastes are scrap metal and spent metalworking fluids and oils. The metalworking fluids can become contaminated or spoiled after use and reuse. This fluid waste may be considered hazardous due to the oil content, contamination by metals like cadmium and lead, or if the oils contain chemical additives like sulfur and chlorine. Typically, the scrap metal and metalworking fluids are disposed of or recycled. Due to the nature of the process, metal shavings and oils are mixed together, making recycling difficult.

Pollution Prevention Opportunities in Metal Shaping

Source Reduction in Metal Shaping

Before throwing steel in a recycling bin, a company can set maximum standards for what size pieces go in the bin. If pieces can be cut and reused for the company’s product, they should. In visiting Georgia companies, there was a mixture of those who segregate by size and those that do not. Companies should also consider the economics of having plate, pipe, and structural members cut to length by their supplier, eliminating solid waste and some costs associated with cutting operations. Recycling generates revenues of $0.02 to $0.03 per pound of low carbon steel while purchased steel shapes can cost $0.30 per pound and up. Our site visits indicated that most fabricators take advantage of recycling opportunities; however, some of the steel being recycled could potentially be reused at a higher value with additional segregation and coordination.

With oils, companies may consider standardizing the types used for machining and similar processes to reduce the number of equipment cleanouts and the amounts of mixed wastes. Use of synthetic fluids can often significantly increase fluid life. For some applications, air can be used as a coolant replacing the oils. Laser cutting, water jet cutting, plasma arc welding, and CNC (computer numerical control) machining are all potential technologies that can be considered for reducing wastes in high volume shops, or those with high dollar value parts. However, each of these “high-tech” methods may have formidable capital cost requirements for small fabricators.

Recycling or Reuse Opportunities in Metal Shaping

One key objective in effective waste management is to segregate the waste streams as they often have greater value (or lower cost) as separate materials. One common example for metal fabricators is the waste mixture of an oil coolant and metal shavings found in many shops due to milling, cutting, drilling, and similar operations. With the use of a “chipwringer,” or centrifuge, oil and metal shavings can be separated to a high degree of purity. Once separated out, the oil can be reused as a coolant and the metal can be recycled. Unless this is done, this waste is typically landfilled or sent to a recycler at a cost to the company. Depending on the amounts of waste, the reduction in coolant oil purchases, and recycling prices for steel, the purchase of a chipwringer often has a quick payback for Georgia companies. As the oil is reused, biocides may need to be added to extend the coolant life.

High performance hydraulic fluids can often be downgraded and used as cutting oils, reducing purchasing and waste amounts for cutting fluids. Additional methods besides centrifugation for recycling oils include filtration, ultrafiltration for water removal, skimming, and coalescing. A plant may consider listing materials on a waste exchange which gives buyers and sellers of miscellaneous wastes a networking opportunity to connect with other companies that can use their wastes. The opportunity may also exist for the company to sell their used oil for burning purposes, reducing their disposal costs while contributing to a reduction in fossil fuel usage.

Waste Generation from Metal Plating Operations

Types of Businesses Using Process

Companies in SIC 3470’s are the most common users of metal plating operations. However, many of these companies operate under a job shop environment providing services for other metal fabricators. Some metal fabricators may choose to do their own plating, and their SIC code would match their product rather than the 3470’s. These companies are primarily involved in electroplating, plating, anodizing, coloring and finishing of metals. The companies in SIC 3479 also get involved in enameling, lacquering, varnishing, hot dip galvanizing, and engraving.

Common Characteristics

A wide variety of materials and processes are used to clean, etch, and plate metallic surfaces. The materials include acids and bases for etching, and solutions of metal salts and other compounds to plate a finish onto the metal. Physical, chemical, and electrochemical processes are all used to finish the pieces. Finishing may be performed to improve appearance or to change the surface properties of the metal. Metal deposition activities include anodizing, conversion coatings, electroless coatings, electroplating, and etching. Anodizing is an electrochemical process which converts the metal surface to a coating of an insoluble oxide. Formation of oxide occurs when the parts are made anodic in dilute sulfuric or chromic acid solutions. Conversion coatings include any operation that uses chromating, phosphatizing, metal coloring, or passivating. Electroless plating consists of the chemical deposition of a metal coating on a part in immersion when electricity is not involved. Electrocoating produces a thin surface coating of metal on another by electrodeposition. Ferrous and non-ferrous materials are typically coated with copper, nickel, chromium, brass, zinc, and cadmium among other metals. Chemical etching dissolves the surface of a metal to provide a specific surface appearance. All of these metal deposition finishing operations take place using plating baths with cleaning and rinsing baths typically upstream and downstream of the metal deposition procedure. As we will see, this provides for several waste minimization opportunities that will be similar across these different processes.

Waste Generation

The metal deposition operations typically result in solid and liquid wastestreams containing chemicals and metals. Air emissions can be a concern also depending on the vapor pressure of the bath or cleaning chemicals. Liquid wastes come from rinsing operations and spent process baths. Plants involved in this field have centralized water treatment plants that result in wastewater treatment sludges. Companies in Georgia claiming SIC codes in the 3470’s typically have these plating baths and the wastes are documented by the large amounts of transfers of sludges off site recorded in TRI reports.

Pollution Prevention Opportunities in Metal Plating Operations

Pollution Prevention by Modifying Equipment

Maintenance and replacement of leaking tanks, piping, valves, and seals along with good housekeeping in general are critical to reducing wastes. Some plants have had to replace leaking process tanks with new tanks. Before spending money on other options, the manufacturer should make sure that their existing tanks and equipment are in good operating condition. Other modifications implemented in Georgia include the installation of a drag-out tank to recover process chemicals, installation of controls for process bath temperature and concentration, addition of drain boards, motorized lifts, and air knives to reduce drag-out. Addition of rinsewater tanks to make a multiple tank, counter-current flow system drastically reduces water usage. At times, manufacturers have been reluctant to make these changes due to space and cost constraints.

Use Low Concentrations for Plating

Keeping the chemical concentration at the lowest acceptable operating level will reduce the loss of process chemicals due to dragout. To find this level, the plater may need to perform trial and error reductions of chemical amounts from that specified by the supplier. At some point, quality will be affected so the concentration must be kept at a high enough level to ensure product integrity. Monitoring of baths should be an ongoing process to allow for continued use of low chemical concentration baths. This requirement can be difficult to meet at understaffed plants.

Recover Metals from Plating Operations

In the past, for most plating lines, it was not cost-effective to recover metals from wastewater or spent process baths. However, current effluent pretreatment regulations and treatment and disposal costs may make it a viable option. Recovered metals can be returned to baths, sold or returned to suppliers, or sold to a reclaimer. Technologies for recovering metals and metal salts include evaporation, reverse osmosis, ion exchange, electrolytic recovery, and electrodialysis. The volume of waste, concentration of metals, potential for reuse, and treatment and disposal costs all factor into the viability of these options. Typically, platers in Georgia will only install these systems if there is a good payback on their investment. P²AD’s library contains literature on each of these options. In addition, platers can contact vendors or technical societies like the American Electroplaters and Surface Finishers (AESF) and National Association of Metal Finishers (NAMF) to find out what successes and failures platers have had with these technologies.

Raw Material Substitution or Product Elimination in Plating Operations

Some Georgia firms have eliminated the use of plating materials including cyanide and cadmium. This has either been done by material substitution or elimination of a product line. There is a current trend to switch from hexavalent baths to trivalent chromium decorative plating and zinc conversion coating solutions. Both these substitutes can offer cost savings in the form of lower wastewater treatment chemical usage since the hexavalent chromium reduction step is eliminated. When considering a product change, platers are concerned with quality, regulations, cost, and health and safety concerns. Actual changes to the metal product like drilling holes in the part to reduce dragout are difficult to make as most platers work in a job shop environment. Those who fabricate and plate their own parts may consider changes to the design of their product to minimize waste generation.

Metal Fabricators – Lack of Technical Resources

• Company Size

45% of Georgia fabricated metal products manufacturers employ 10 persons or less. These companies are unlikely to have technical or engineering resources on their payroll. In mid-size companies, one engineer may have several responsibilities including safety, environment, process optimization, and plant engineering, leaving little time for implementing a formal pollution prevention program. Large firms have also been affected by cutbacks and personnel have had to take on more responsibilities. For varying reasons, the different sized firms continue to have difficulties dedicating any staff time to pollution prevention activities.

• Location

Manufacturers are located throughout Georgia. Geographically, this makes it difficult for employees to have access to technical associations or professional societies. Currently, there is little opportunity for these employees to take part in formal networks related to their industry sector or the environment.

• Technical Assistance

There are many state, federal, and university programs available to Georgia companies to assist in various aspects of the environment and their technical processes. However, few companies take advantage of these resources. Small companies, in particular, do not seem to use these resources, yet they may be the companies that need this outside expertise the most. 34% of metal fabricators surveyed indicated that limited in-house expertise is a barrier to pollution prevention. Smaller companies with less than eleven employees perceived limited in-house expertise as a barrier at a much higher rate than other companies. This would indicate that many manufacturers might benefit from assistance from outside sources.

• Industry and Technical Associations

Companies in SIC 34 make many different products. Typically, the industry associations are aligned with the specific product, i.e., metal doors, metal cans, electroplating, or coil coaters. Therefore, there does not appear to be a strong industrial association presence in the state that addresses the needs of all metal fabricators. This again limits networking opportunities.

Pollution Prevention Assistance Needs of the Fabricated Metal Products Manufacturing Sector

Organizational and Technical Needs

Technical Staff or Support

80% of the metal fabricators in the state have 50 employees or less. Therefore, they often feel they do not have the manpower or expertise to investigate pollution prevention issues. It is difficult for a small plant to keep current with the latest technologies and determine their relevance to the company’s operations. Also, employees typically juggle several responsibilities which prevents them from focusing on pollution prevention.

Overcoming Resistance to Using Outside Groups for Assistance

Metal fabricators, small shops in particular, typically work within their own organization or with their equipment or chemical vendors to address waste minimization concerns. Despite P²AD’s separation from the Environmental Protection Division, companies are still hesitant to work with a government agency. The resources to help companies are available, but they are either not aware of the free services, or are reluctant to invite outsiders into their plants.

Education on Pollution Prevention Concepts versus Waste Treatment

Metal fabricators’ top concern is making a profit and staying in business. Environmental issues are perceived as being an obstacle to that goal. Many fabricators do not distinguish between waste treatment and pollution prevention at the source. Source reduction and reuse can make good economic sense in addition to good environmental practice. Until people are made aware of the difference, pollution prevention will not be looked at closely; compliance will continue to be the main thrust of fabricators’ environmental initiatives.

Correctly Targeting Assistance

Less than half of the companies surveyed perform surface preparation activities, while only 57% do some form of painting, and 14% have a plating operation. These are traditional areas where pollution prevention can have an immediate and dramatic effect on metal fabricators. However, many companies will not be interested in this information as it is not relevant to their operations. Other areas such as metal shaping and solid waste reduction should be considered as topics for this large portion of the industry. Technical assistance associations must understand the current needs of their target audience.

Barriers to Pollution Prevention

64% of the survey respondents listed barriers to pollution prevention. Companies could use practical assistance in overcoming specific barriers.

Formal Pollution Prevention Programs

Companies might be more productive in evaluating, implementing, and benefiting from pollution prevention opportunities if they had a formal method for identifying and evaluating waste reduction activities. The formal program could be used to ensure that all personnel are aware of the benefits of pollution prevention and will be continually looking for improvements to the current process or product.

Technology Transfer

It is difficult for a company to keep up with the newest technologies in all areas of their operations. A conduit for keeping firms updated with the latest economic and feasible technologies would be helpful. Companies could also use assistance in evaluating the technologies and materials for their specific needs.

Technologies

The closer a technology can be to a “drop-in replacement,” the more likely a company will be willing to try it. The less variables in a process it affects, the better a company will be able to judge the chances for success.

Meeting Organizational and Technical Needs

Lack of Technical Staff

To attract more companies to their services, the not-for-profit service agencies should consider developing more outreach activities to the small and mid-size companies. These companies clearly lack the resources that larger companies have. In addition, the smaller companies may want to become more involved with technical associations specific to their industry. There are dozens of product specific metal fabrication associations that are available to these industries at a small cost. Annual trade shows and conferences may also be a good place for small companies to keep up with the latest technologies and meet vendors, government and university technical assistance providers. Chambers of Commerce and Georgia Tech’s Economic Development Institute may be effective means of reaching smaller plants.

Hesitance to Use Outside Groups for Assistance

Industry trade groups should be an excellent resource for companies. However, their meetings may not be geographically convenient due to Georgia’s size. It may be helpful to create regional networks of industries within Georgia. This would be a convenient way to learn about other plants’ trials and successes in waste minimization and a host of other topics. The opportunity to discuss operations with other metal fabricators and related industries at a convenient location may help more companies take advantage of current best practices and technologies.

For companies unaware of free services in Georgia, a listing follows of agencies that provide technical process and environmental assistance to manufacturers.

Georgia Tech Economic Development Institute Georgia Institute of Technology 209 O’ Keefe Building Atlanta, GA 30332 404/894-3950 The University of Georgia Driftmier Engineering Center The University of Georgia Athens, GA 30602-4435 706/542-8382 Georgia Tech Research Institute Georgia Institute of Technology Electro-Optics, Environment and Materials Laboratory Environmental Engineering Branch Atlanta, GA 30332-0837 404/894-3806 Georgia Department of Natural Resources Pollution Prevention Assistance Division Ste 450, 7 M.L. King Jr. Drive Atlanta, GA 30334-9004 404/651-5120 800/685-2443

P²AD’s library includes a publication entitled National Trade and Professional Associations of the United States. Therefore, P²AD can assist metal fabricators in locating technical societies that are relevant to specific subsets of SIC 34.

Understanding of Pollution Prevention Concepts Versus Waste Treatment

Basic pollution prevention training on a regional basis may be the best way to reach a wide audience and teach them the benefits of pollution prevention versus waste treatment. Chambers of Commerce, local utilities, or Georgia Tech’s Economic Development Institute may be good cosponsors to provide successful seminars. Compliance training in conjunction with pollution prevention training may draw better attendance at events. Also, the upcoming Georgia Pollution Prevention Partners recognition program will help publicize success stories of Georgia fabricators and build a better understanding of the P2 concepts for others.

Correctly Targeting Assistance Needs

This study has helped the P²AD staff understand the variety of needs of metal fabricators in the state. With this information, P²AD should be better able to develop relevant programs to metal fabricators and the other industry groups in this study. Companies in different SIC codes may have different needs and smaller companies may have different requirements and constraints compared to the larger plants. P²AD should consider these factors in providing technical assistance and seminars.

Barriers to Pollution Prevention

Until a company can see the economic benefits of pollution prevention, it is unlikely that they will invest much time in it or initiate a program. P²AD is currently conducting studies with industry partners in the area of environmental management systems and full cost accounting for wastes. Ideally, the knowledge gained here will be transferred to other companies to better demonstrate the costs of creating wastes and the full benefit to be gained through pollution prevention. In addition, companies should consider using outside sources for ways to break down the stated barriers.

Formal Pollution Prevention Programs

P²AD has the expertise in pollution prevention to provide companies with training or assistance in setting up formal pollution prevention programs. In addition, our P2 library contains several documents to assist a company in setting up a structured program. However, a company needs to become aware of the benefits of P2 before it will set up a program. For this reason, P²AD has developed the Pollution Prevention Partners (P³) program as a means of getting companies involved in formalized pollution prevention. P³ is a multi-tiered recognition system that rewards companies for setting up programs and demonstrating results.

Technology Transfer

Three potential methods for aggressively pursuing technology transfer of pollution prevention technologies include fact sheets, seminars, and regional networks. All three of these steps are being undertaken by P²AD. Fact sheets are being developed as a follow-up to in-depth pollution prevention assessments of manufacturers in the state, particularly where the P2 initiative is relevant to many firms. Seminars specific to the metal fabrication sector will be developed by P²AD in conjunction with the Georgia Tech Economic Development Institute (GT EDI). The metal fabrication seminar will be presented in 1997. Finally, P²AD and GT EDI are planning on setting up regional networks of industry in the state loosely based on the location of GT EDI field offices. The intent is to have industry address environmental concerns including pollution prevention on a regional basis to limit their time and travel requirements while developing solutions and technology transfer across industries. This interaction should help companies sort through the valuable P2 technologies versus those that have had limited success.

Technologies

Metal fabricators should continually push vendors toward less hazardous drop-in replacements for existing processes. One effective means of doing this may be through technical associations such as AESF and NMFA, or through regional networks of companies.

Suggested Readings for More Detailed Coverage of Pollution Prevention Concepts

The details within this report are limited due to the far ranging scope of the topic. Therefore, the following references are listed to give the reader an opportunity for more detailed information. For information on obtaining these documents, Georgia residents and companies may wish to contact the Georgia Pollution Prevention Assistance Division at 404/651-5120 or 800/685-2443. Outside of Georgia, use the EPA Pollution Prevention Directory listed below to locate the appropriate state or federal assistance program.

Anderson, Beth, Pollution Prevention Directory, US Environmental Protection Agency, EPA 742-B-94-005, September 1994.

Brown, Lisa M., Guides to Pollution Prevention: The Fabricated Metal Products Industry, US Environmental Protection Agency, EPA/625/7-90/006, July 1990.

Brown, Lisa, Facility Pollution Prevention Guide, US Environmental Protection Agency, EPA/600/R-92/088, May 1992.

Cushnie, George C., Jr., Pollution Prevention and Control Technology for Plating Operations, National Center for Manufacturing Sciences, 1994.

Freeman, Harry M., Industrial Pollution Prevention Handbook, McGraw-Hill, Inc., 1995.

Harten, Theresa, Guides to Pollution Prevention: The Metal Finishing Industry, US Environmental Protection Agency, EPA/625/R-92/011, October 1992.

Higgins, Thomas E., Pollution Prevention Handbook, CRC Press, Inc., 1995.

Murphy, Michael, Metal Finishing: Organic Finishing Guidebook and Directory Issue, Metal Finishing Magazine, May 1995.

Williams, Douglass, Guide to Cleaner Technologies: Alternatives to Chlorinated Solvents for Cleaning and Degreasing, US Environmental Protection Agency, EPA 625//R-93/016, February 1994.

Williams, Douglass, Guide to Cleaner Technologies: Cleaning and Degreasing Process Changes, US Environmental Protection Agency, EPA 625//R-93/017, February 1994.

Summary and Conclusion

The purpose of this study is to identify the pollution prevention needs of the Georgia fabricated metal products industry. This information will be used to develop programs within P²AD to address industry needs. Highlights of the report are outlined below.

• Key areas where pollution prevention activities can benefit Georgia metal fabricators include coatings application, surface preparation and cleaning, painting, and plating.

• Available waste minimization technical assistance has been underutilized by metal fabricators in Georgia. P²AD has been in existence for less than three years and should continue their efforts at reaching the metal fabrication sector, particularly the small and mid-size companies.

• To fully develop a pollution prevention ethic in the industry, P²AD should confront some of the needs outlined in this paper. Specific tasks to meet these needs have been suggested within this paper.

Appendix I

Appendix II

Biennial Reports

Company Pollution Prevention Successes Based on Hazardous Waste Reduction Plan and Progress Reports

SIC 34

• Coil Coaters of America reduced their generation of paint wastes by 10 % by tinting and reusing 55 gallons of waste paint each month. They also substituted lime for sodium hydroxide as a neutralizing agent and reduced their generation of filter cake.

• AWH Royston Plant has switched to a high volume solids paint. In addition, they have implemented powder coating to the extent possible.

• American National Can reduced overspray in a process by reducing pump pressure from 800 psi to 700 psi.
• Har-Conn Chrome has improved production scheduling such that individual paint guns are used for only one type of paint and the operator determines how much paint will be needed for the day. This has reduced their need for solvent cleaning and their paint wastes. The company has also reduced plating tank dragout by adding hanging bars over process tanks to allow parts to drip for a longer time reducing rinsewater contamination.
• Kason Industries has installed lower flow restrictors on their nickel plating and copper plating lines. The flow on copper line has been cut from 10 gpm to 2.5 gpm while tank dumps have been reduced from every week to every two weeks. Thi