logo Pollution Prevention in Metal Finishing: Plating
A Northwest Industry Roundtable Report



The Pacific Northwest Pollution Prevention Research Center (PPRC) held a roundtable discussion on June 20, 1995 in Seattle, Washington, on pollution prevention issues facing the plating sector of the metal finishing industry in the Northwest region of the United States. The majority of meeting participants were from the Puget Sound area, and included representatives of the metal plating industry, government, the academic community, distributors/vendors, researchers, and the PPRC.

Funding for the roundtable was provided by a grant from The Boeing Company. The PPRC, with support from Boeing, organized this roundtable for several reasons:

The purpose of the roundtable was for participants to share pollution prevention experiences, identify challenges to the implementation of pollution prevention approaches, discuss sources of information and routes of communication, and develop recommendations for efforts to help disseminate essential information and expedite the adoption of alternative technologies.

The roundtable meeting, and subsequently this report, address issues only in the metal plating sector of the metal finishing industry — that is, the application of a metal coating onto a metal part (metal deposition technologies). Metal finishing also includes: the application of paint and related materials onto metal (organic finishing technologies); finishing methods in which the "plated" materials interact with and physically change the make-up of the metal part — anodizing, phosphating, and chromating — (conversion technologies); and subtractive processes that involve the removal of metal from the metal part either through physical action or chemical reaction (removal technologies). Many companies that perform metal finishing operations offer many of these services. However, these technologies were not discussed at the meeting and, therefore, are not addressed in the report. Additionally, activities associated with electroplating printed circuit boards are not included.

This report includes an overview of current and emerging pollution prevention practices and projects at metal plating facilities in the Northwest, and a summary of roundtable discussions, including:

At the conclusion of the meeting, metal platers developed a list of recommendations for future activities that would encourage the transfer of information and the further adoption of pollution prevention approaches. These recommendations are summarized at the end of the report.

Appendix A provides a list of roundtable participants, Appendix B provides an overview of the industry and the primary metal plating processes, and Appendix C includes the primary chemicals used in metal plating that are of environmental concern.


Northwest Metal Finishing Industry: Plating

This section is intended to provide a general introduction to the metal plating industry in the Northwest. For more information on the industry in general, specific processes, chemicals, waste streams, and environmental regulations, refer to the appendices at the end of the report.


Industry Characteristics

A significant amount of metal plating in the Northwest is found within companies that manufacture products rather than those that specialize in metal plating. These are referred to as "captive" operations. However, a great deal of metal plating is contracted to independent establishments, called "job shops." The largest concentration of metal platers are located in the Seattle, Washington, and Portland, Oregon, metropolitan areas; at least 75 percent of the shops in the region are in or near these cities. The exact number of facilities that perform metal plating services in the region is difficult to determine because the facilities are regulated under a variety of SIC codes. In addition, many of the shops are one- or two-person operations, and may not be properly registered within government agencies. Metal plating job shops in the Northwest range in size from one employee to just over 100. Total employment in the Northwest is somewhere between 2,000 and 3,000 people, with the largest markets being aerospace and military applications.

Pollution Prevention in Metal Plating

Pollution prevention is the reduction or elimination of waste at the source, or closed-loop recycling that takes place in the facility. In some cases, pollution is reduced not by reducing the quantity of material used but by substituting a less-toxic and/or non-regulated material for the material previously used. In other cases, the efficiency of the process is increased, thereby reducing the actual quantity of waste. Pollution prevention projects reduce the need for the treatment, transport, and disposal of wastes, and in many cases, offer financial benefits to companies.

Factors Resulting in Pollution Prevention
Northwest metal plating shops have implemented a number of pollution prevention projects within their facilities, particularly in the past five years. This increase in pollution prevention activity is the result of a number of factors, including:

It is interesting to note that each of these factors are barriers to pollution prevention implementation. What has occurred over the last several years has been a reduction in these barriers and an increased interest in pollution prevention.

Pollution Prevention Activities and Projects
The following information was compiled from studying a number of pollution prevention plans and annual progress reports submitted to the Washington Department of Ecology between 1991 and 1995, and through subsequent conversations with employees at several metal plating shops whose plans were reviewed. It is important to note that many pollution prevention approaches available to metal platers are not discussed in the section below because they were implemented prior to 1991 or because they were not identified as being implemented in any of the companies studied. Nonetheless, the information below provides a general overview of the types of pollution prevention techniques that are feasible. These projects are loosely organized in the order of the typical process flow, which is discussed in Appendix B.

Other Projects
A number of other types of projects have been implemented at Northwest companies that are more general in nature as opposed to being associated with a specific process step. They include:


Roundtable Discussions

This section includes a summary of several of the main topics discussed during the roundtable meeting. It’s important to note that the following information represents the opinions of roundtable participants, the majority from the Puget Sound area, and may not reflect the views of all metal platers in the Northwest.

Platers Are Interested in Trying Pollution Prevention Approaches

Meeting attendees cited several pollution prevention approaches they are interested in trying, but have not implemented due to a lack of knowledge of the technology, insufficient financial resources or other reasons. These approaches include a mobile acid purification unit, the recovery of alkaline degreasing solutions, a practical evaluation of rinsewater reuse, and the recovery of sodium hydroxide from strip waste.

Mobile Acid Purification Unit
Acid purification uses ion exchange to process/purify plating baths. A unit consists of columns containing resin beads that selectively remove ions from a solution that passes through the column. This column is referred to as an ion exchange column. In this case, an acid plating bath would be pumped through the column to remove metal ion impurities that are interfering with the plating process.

The metal platers at the meeting discussed the possibility of sharing a single, mobile unit. The high-cost of the equipment makes it economically infeasible for a single shop to purchase a unit. With a shared unit, each shop would have its own resin beads, which would be used in the unit to purify the acid baths. When finished with the unit, the shop would remove its resin, rinse the unit, and ship it to another co-owner. The resin could not be shared among companies because each company’s baths may contaminate the resin to a different degree, and because of concerns with transporting contaminated resin (which could be designated as a hazardous waste). Sharing a unit would be feasible because bath purification is typically needed only several times per year and takes a few days at most to complete, including loading and unloading resin.

Prior to making the joint investment, the shops want to obtain reassurances from the Washington Department of Ecology that sharing and transporting a mobile acid purification unit would not put the shops out of compliance with any existing or soon to be implemented regulations.

Recovery of Alkaline Degreasing Solutions
As discussed earlier, a majority of metal platers have converted from using vapor degreasers to using alkaline degreasing solutions. The solutions have created a new wastewater stream, since most shops do not purify and recycle the cleaners. Microfiltration has been identified as a potential process to remove and reuse oils from cleaning solutions. However, when oils are removed using microfiltration there is also the potential to remove the surfactants that make the solution capable of cleaning the part. Detailed technical information, including local testing of the microfiltration process, is of interest to the metal platers that participated in the meeting. They would use this information to successfully implement an alkaline degreaser recovery process at their shops.

Practical Evaluation of Rinsewater Reuse
The waters that rinse excess chemicals off parts removed from process baths have the potential to be reused if processed properly. A small portion of metal plating shops throughout the country already do this using a combination of ion exchange, electrowinning, and reverse osmosis.

As discussed above, ion exchange is used to selectively remove metal ions that are impurities from solutions. Electrowinning can be used on the metal concentrate that is flushed from a saturated ion exchange unit. Electrowinning is a process by which the metals are deposited onto metal cathodes using electrical current. When these cathodes become fully loaded, they can be removed and sold for their scrap metal content.

The water leaving the ion exchange unit can be further processed by a reverse osmosis unit to remove a majority of the dissolved salts from the water. Water leaving the reverse osmosis unit can potentially be reused as new rinsewater instead of being discharged. The platers at the meeting were interested in obtaining more detailed performance information related to rinsewater reuse, and having a local demonstration project performed where the results would be shared among all companies.

Recovery of Sodium Hydroxide from Strip Waste
As part of the surface preparation done prior to plating, some shops use a sodium hydroxide strip rather than the acid dip, which is shown in Figure 1 in Appendix B. One metal plater that uses sodium hydroxide strip expressed an interest in being able to process and recover this solution rather than dumping the bath when the solution is spent. At this time, there is no identified method for recovering this stream.


Information Platers Need to Implement Pollution Prevention Approaches

Metal platers at the roundtable cited three primary pieces of information they need to implement new technologies, such as the pollution prevention approaches mentioned above. These include: a need to know the technology works, a need to be able to justify the cost of the investment, and a need to know the alternative technology would not put them out of compliance with existing regulations.

It was the consensus of the platers from several job shops who attended the meeting that they need to be confident a new technology will actually work before they implement it. Actually knowing a process change will be both effective and cost-efficient means gathering information from a variety of sources. These sources include talking to suppliers, other metal plating shops, and larger companies (such as Boeing), as well as locating case studies and attending demonstrations. Several platers said that when considering a new technology it is essential to get firsthand information from other companies in the Northwest that have actually used the product. According to one metal plater at the meeting, seeing a demonstration of a new technology in person also helps in the decision-making process, because it gives platers the opportunity to see firsthand the results of the technology.

Cost Justification
The ability to determine the costs and benefits of a new technology is essential, according to a plater from a job shop, and this information plays a major role in management’s decision to adopt it. Most metal platers in the group agreed, adding that if they are unable to calculate the costs of a pollution prevention approach, it is difficult to persuade management to make the investment. A representative from the Washington Department of Ecology said the department has university students conduct assessments to businesses free of charge using a total cost assessment software package called P2/FINANCE, and offered this service to the metal platers at the meeting. Platers can also purchase the software for approximately $40 for their own use, however, he cautioned against this, saying it can be difficult to learn. A representative from the University of Washington suggested plating shops could participate in an internship program with the university to assist with cost justification. The shops would benefit by gaining a student researcher, and the students would benefit by getting firsthand work experience. Platers at the meeting were receptive to these suggestions.

Technology Must Meet Existing Environmental Regulations
Metal platers also voiced a need to know that implementing the new technology would not put them out of compliance with existing environmental regulations. Prior to making a change in their processes, the platers discuss the alternative with a representative from the section of the regulatory agency that might be affected. For example, the elimination or substitution of a specific chemical used in the plating process may have an affect a facility’s wastewater discharges, which are regulated under the Clean Water Act. Such a change could require a modification to the facility’s discharge permit, causing the facility to delay implementation until approval from the regulatory agency is granted. This waiting period can be a source of frustration for some platers who are ready to implement a pollution prevention technology but are held up by the regulatory process.


Sources of Information for Metal Platers

The metal platers in attendance were asked to discuss the sources of information they use to assist them in making decisions related to the selection and use of new processes and products. According to participants, they obtain information from a number of sources. Understanding these sources can assist researchers, technology developers, government agencies, and others in their efforts to successfully disseminate research results, new technologies, and other types of information to those in the metal plating industry. The sources of information cited by participants are listed below.

Vendors and Suppliers
Several participants stated they rely heavily on process chemistry and recovery and treatment equipment suppliers for information on technology availability and proper operating practices, because engineering resources are a precious, and often rare, commodity for metal platers. For many shops, process engineering expertise is based on cumulative know-how of experienced platers and guidance from suppliers rather than on formal, internal engineering expertise, according to meeting participants. And, because process chemistries are becoming increasingly complex to understand and maintain, plating facilities are relying on their suppliers more than ever to provide assistance and instruction. Participants said this is especially true for the smaller, independent metal plating facilities, where budgetary constraints do not often allow for the hiring of outside consultants or in-house engineers. When a finisher finds a supplier he trusts, the supplier can become his primary source of technical information.

One of the platers at the meeting acknowledged that the downside of vendor-provided information is that a vendor is primarily interested in "making a sale," and that his job is not necessarily to be a technical expert in a product’s use. Several platers cited the importance of getting local references from vendors, and not solely relying on the advice of suppliers. This way, they said, the information comes firsthand from other companies in the Northwest that have actually used the products at their facilities. Another issue that was brought up by several participants from smaller plating shops was that most out-of-town vendors would not make special sales calls to the smaller companies. They said out-of-town vendors typically make appointments to visit the smaller businesses only when they are already going to be in town to visit a larger finisher (such as Boeing). This has irritated many platers, making them resistant to work with some vendors, according to one attendee.

Other Platers
The metal platers at the meeting cited their peers (other platers) are a primary source of information regarding new technologies. They said that information from fellow platers is typically based on firsthand experience and, therefore, is highly reliable.

Low price, delivery time, and quality are three important competitive issues for metal plating companies. Since many job shops may be in competition with one another, they do not often openly share information, for fear of losing any competitive advantage they may have. However, participants agreed that if the information regarded a waste from a proprietary process, as opposed to the process itself, they would be more likely to share this information with other plating shops.

The Boeing Company
Some independent metal plating companies, especially those located in the Puget Sound area and/or those that contract with Boeing, rely on Boeing to test the economic feasibility and effectiveness of a new product or process before trying it themselves, according to meeting participants. Often, this is because the shops are required to meet certain specifications, which Boeing requires in its contracts. One plater who does not contract with Boeing asked how he could find out about new technologies Boeing is currently testing. Earl Groshart, a representative from Boeing, said the company offers this type of information to any shop that requests it. For information on technologies Boeing has tested or is currently testing, he suggested platers should contact him (see Appendix A).

Professional Organizations
The platers at the meeting agreed that they gain a lot of their information from professional organizations. The primary trade associations in the Northwest are the local chapters of the American Electroplaters and Surface Finishers (AESF) and the National Association of Metal Finishers (NAMF). These organizations hold national meetings once a year, and the Puget Sound chapters, for example, sponsor monthly meetings. Membership in AESF is open to all surface finishing professionals, as well as to those who provide services, supplies, and support to this industry. NAMF is comprised of management executives, including owners of metal finishing and related businesses. It is important to note that the companies represented at the meeting are very active in these associations, but there are many metal shops in the Northwest that do not utilize them.


Sources of Information Not Cited by Metal Platers

As mentioned earlier, a tremendous amount of research has been conducted in the metal plating industry, and there are a wide range of resources are available to metal platers. But, several platers at the meeting said they were unaware of the amount of research that had been done, and do not know where to get the information to aid them in their decisions to implement new technologies. Another meeting attendee pointed out that "there appears to be too much of a good thing," suggesting the need for the information to be synthesized to be useful to most platers.

Several major sources of information meeting attendees failed to mention include state and federal government, the national laboratories, National Defense Center for Environmental Excellence - Concurrent Technologies Corporation, and the academic community.

It is interesting to note that the platers at this meeting did not cite government as a primary source of pollution prevention information, although there are an abundance of resources available at both the state and federal level. A failure to cite government may be because metal plating has been a target for regulatory inspection and enforcement, so many plating shops are hesitant to "call attention" to themselves by asking for assistance. Nonetheless, federal and state agencies offer a wealth of information, providing reports, case studies, newsletters, technical assistance, and other resources to metal platers. One plater mentioned the Washington Department of Ecology’s newsletter, Shoptalk, as containing useful information.

National Laboratories
Metal platers at the meeting do not get information on new technologies from the national laboratories. However, a participant from Battelle Seattle Research Center asked metal platers if having access to third-party technology evaluations from the national laboratories (such as Pacific Northwest Laboratory) would help them make decisions regarding the implementation of new technologies. Several platers said having a scientist work with their company to evaluate a new technology would be valuable.

National Defense Center for Environmental Excellence - Concurrent Technologies Corporation
Concurrent Technologies Corporation (CTC) is an independent nonprofit organization that provides training in the use of new technologies, and supports applied research and development to transition new technologies. CTC, which has an office in Bremerton, Washington, operates the National Defense Center for Environmental Excellence. The NDCEE was established to support Department of Defense facilities and the associated industrial base in adopting a comprehensive approach to pollution prevention. CTC offers a variety of resources that could be beneficial to metal platers, including case studies, online information searches, training, and more.

Academic Community
Meeting attendees did not mention universities as a source of information. A member of the academic community who attended the meeting said that faculty are very interested in understanding the processes used by the job shops, in an effort to better understand what they need from acadamia. He suggested the metal platers work with universities to set up internship programs, which would provide students with industry experience, serve as conduits for faculty to keep in contact with industry needs, and provide the metal job shops with a student researcher to assist with cost justification. Several metal platers were highly receptive to this idea.


Information Media Used by Platers

According to roundtable participants, the media used most frequently for information exchange among metal platers are verbal exchanges and printed materials, as opposed to online resources. Platers at the meeting said they are just beginning to use online resources to access information.

Verbal exchanges take place in informal and formal discussions, meetings, seminars, and conferences. Meeting participants saw a need for more forums (such as this roundtable), to bring together representatives from all sectors (government, acadamia, researchers, vendors, and others) to discuss pollution prevention issues in metal plating. Currently, a group of metal platers get together regularly at professional association meetings, and talk one-on-one with vendors, but rarely have the opportunity to talk with university faculty, technical assistance providers, and others. Many platers said they prefer receiving information in hard copy form, as opposed to conducting their own online information searches. Printed information (in the form of newsletter, reports, case studies, and other materials) is currently sent to platers by government agencies, vendors, and nonprofit organizations.

One plater noted that an increasing number of platers are starting to use personal computers to access and retrieve online information. However, many of the smaller shops said they do not have online capabilities. While this medium was not currently considered a primary mode of information transfer, most meeting participants agreed that it is rapidly becoming a increasingly important way for platers to access information. Public libraries, the PPRC, the Washington Department of Ecology, CTC, and many other organizations offer online information searches at little or no charge. Several platers said that having access to online resources would be useful.


Technology Transfer Support from Boeing

There is currently no formalized effort for technology transfer from Boeing to the independent metal platers. Often, information on new technologies is transferred to subcontractors for Boeing through the contracts. The specifications in the contracts dictate the types of equipment and processes the independent metal shops can use. Because plating shops are in such fierce competition with one another, if a contract specifies a specific pollution prevention technology, the contractors will use it. At the same time, if the contract specifies a more toxic approach, the platers must use that method.

Many product or process changes are capital intensive, and many shops cannot afford the initial investment or risk losing production time. Therefore, according to one plater, when Boeing tests a new process and approves it, many smaller companies see this as a "green light" — that they can implement the process with relatively little risk. A vendor at the meeting supported the theory that job shops watch the activities of Boeing by saying, "When Boeing looks at a new technology, other metal platers look at it too."

In the past, Boeing has sponsored one-day seminars on new technologies, which were held at a local community college on Saturdays. Several platers who had attended some of the classes said they were useful, and helped them make some choices regarding new processes. In addition, they said they liked the fact that attendees received a certificate of completion for attending. Platers said the most useful information gained from these seminars were case studies and practical information. However, platers did not recommend continued seminar offerings, as it is very difficult for workers to find time to attend.



At the conclusion of the meeting, the metal platers were asked to prioritize the future activities they see as essential to providing them the information they need to implement the pollution prevention approaches they are most interested in. Roundtable participants stressed the need for networking through regular meetings, access to case studies, demonstrations of the processes they are considering implementing, access to cost justification tools, and technology transfer from Boeing and others. The needs agreed upon by the group are listed below from most highly recommended to least recommended.


Regular Meetings

Roundtable participants agreed that there was a need to continue having regular meetings to exchange information regarding pollution prevention technologies. Because attendees cited other platers as a primary source of "reliable" and "firsthand" information regarding new technologies, they agreed that regular, monthly meetings are an excellent means for sharing information. While many job shops may be in competition with one another, participants agreed they would be willing to share information that is not proprietary.

While platers regard these meetings as an excellent forum for sharing pollution prevention experiences with one another, they also voiced the need for an organized forum for hearing from individuals outside the plating community. They said they saw value in meeting face-to-face with not only fellow platers, but representatives from acadamia, government, nonprofits, and others. They cited the roundtable as an excellent forum for improving communication among all sectors.

With these needs in mind, the group made a commitment to invite the PPRC and others working in pollution prevention to speak at the monthly Puget Sound area AESF and NAMF trade association meetings a minimum of once each year. The group also agreed that the topic of pollution prevention should be included at annual, regional AESF/NAMF conferences, and asked the PPRC to be on the agenda at the next meeting. Participants said they would also be receptive to additional forums (such as this roundtable) that include representatives from all sectors.

Case Studies

While considerable information on metal plating is available, many of the platers at the meeting said they are unaware of or are not fully utilizing it when making decisions on pollution prevention approaches. According to one meeting participant, there is so much highly detailed information available that most platers lack the time to locate it and then sort through it to determine what is applicable to them. Attendees conveyed a strong need for condensed summaries of industry-specific case studies regarding the implementation of the new approaches they are interested in implementing: a mobile acid purification unit, the recovery of alkaline degreasing solutions, a practical evaluation of rinsewater reuse, and the recovery of sodium hydroxide from strip waste. In addition, platers are most interested in learning about the pollution prevention experiences of other platers in the Northwest.

Demonstration Projects

It was the consensus of the platers who attended the meeting that they need to be confident a new technology will actually work before they implement it. If they are not confident a pollution prevention approach is feasible, they most likely will not try it. Most attendees agreed that seeing a demonstration of a new technology in person helps in the decision-making process because they are able to see firsthand the results of the technology. Due to the competitiveness of the industry and the importance of keeping proprietary process information confidential, attendees agreed they are most interested in off-site, bench-scale demonstration projects. Metal platers at the meeting voiced a strong need for demonstrations of the following processes: the recovery of alkaline degreasing solutions, a practical evaluation of rinsewater reuse, and the recovery of sodium hydroxide from strip waste.

Cost Justification Tools

Most metal platers in the group said they need access to cost justification tools to determine the costs and benefits associated with the implementation of new technologies, adding that if they are unable to calculate the costs of a pollution prevention approach it is difficult to persuade management to make the investment. Suggested activities included:

Technology Transfer from Boeing and Others

There was limited interest among metal platers at the meeting for having access to information on new technologies from Boeing, the national laboratories, and Concurrent Technologies Corporation (CTC). Some metal plating companies, especially those that contract with Boeing, rely on Boeing to test the economic feasibility and effectiveness of a new product or process before trying it themselves. Often, this is because the shops are required to meet certain specifications, which Boeing dictates in its contracts. For information on technologies Boeing has tested or is currently testing, platers should contact Earl Groshart, Boeing Defense and Space Group (see Appendix A).

In addition, several metal platers at the meeting said having access to technologies evaluated by the national laboratories and CTC would be valuable, and would help them make decisions regarding the implementation of these processes.


Continue to Appendix A: Roundtable Attendees.

Back to the Table of Contents.

© 1999, Pacific Northwest Pollution Prevention Resource Center
phone: 206-352-2050, e-mail: office@pprc.org, web: www.pprc.org