vxEPA
United States
Environmental Protection
Agency
Office of Research and
Development
Washington DC 20460
EPA/600/R-92/046
April 1992
Pollution Prevention
Case Studies
Compendium
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EPA/600/R-92/046
April 1992
POLLUTION PREVENTION
CASE STUDIES COMPENDIUM
by
Johnny Springer, Jr.
Waste Minimization, Destruction
and Disposal Research Division
Risk Reduction Engineering Laboratory
Cincinnati, Ohio 45268
EPA Contract No. 9-C8-031-TNSE
Project Officer:
Johnny Springer, Jr.
Waste Minimization, Destruction
and Disposal Research Division
Risk Reduction Engineering Laboratory
Cincinnati, Ohio 45268
U.S. Environment?! Protection Agency
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OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
Printed on Recycled Paper
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DISCLAIMER
The information in this document has been funded wholly or in part by the United
States Environmental Protection Agency. It has been subjected to the Agency's peer and
administrative review, and it has been approved for publication as an EPA document.
Mention of trade names or commercial products does not constitute endorsement or
recommendation for use.
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FOREWORD
Today's rapidly developing and changing technologies and industrial products and
practices frequently carry with them the increased generation of materials that, if
improperly dealt with, can threaten both public health and the environment. The U.S.
Environmental Protection Agency is charged by Congress with protecting the Nation's
land, air and water resources. Under a mandate of national environmental laws, the
agency strives to formulate and implement actions leading to a compatible balance
between human activities and the ability of natural systems to support and nurture life.
These laws direct the EPA to perform research to define our environmental problems,
measure the impacts, and search for solutions.
The Risk Reduction Engineering Laboratory is responsible for planning,
implementing, and managing research, development and demonstration programs to
provide an authoritative, defensible engineering basis in support of the policies,
programs, and regulations of the EPA with respect to drinking water, wastewater,
pesticides, toxic substances, solid and hazardous wastes, and Superfund-related activities.
This publication is one of the products of that research and provides a vital
communication link between the researcher and the user community.
This report is the first concise collection of summaries of pollution prevention
demonstrations, assessments, and research projects conducted by the Pollution Prevention
Research Branch. The Branch is charged with defining, evaluating, and advancing the
technology for the implementation of a national pollution prevention program. It also
provides technical assistance to other sections of EPA for the purpose of reducing or
eliminating pollution hazards.
The information contained here will serve as a reference work and technology
transfer vehicle to disseminate research results and promote the implementation of
pollution prevention activities.
E. Timothy Oppelt, Director
Risk Reduction Engineering Laboratory
111
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ABSTRACT
The Pollution Prevention Research Program encourages the development and
adoption of processing technologies and products in the United States that will lead to
reducing the aggregate generation rates for pollutants entering the various environmental
media. It includes projects to improve the understanding of environmental problems that
might be amenable to pollution prevention approaches, and projects that demonstrate
innovative pollution prevention approaches and technologies. Pollution Prevention
Research supports studies and research and demonstration projects that are designed to
further the utilization of source reduction and to a lesser degree recycling as preferable
environmental improvement strategies. Projects within the program are supported
through in-house activities, contracts with outside organizations, and cooperative
agreements with universities and other government agencies.
The Risk Reduction Engineering Laboratory (RREL) serves as the lead
organization within the EPA's Office of Research and Development for research related
to pollution prevention. Spearheading pollution prevention research within RREL is the
Pollution Prevention Research Branch (PPRB) of the Waste Minimization Destruction
and Disposal Research Division. Efforts cover all sectors identified in EPA's Pollution
Prevention Strategy (January, 1991), i.e., manufacturing, agriculture, energy and
transportation, municipal water and wastewater, federal facilities and municipal solid
waste. The program also contains a technology transfer element for incorporating results
from other's research and for disseminating the results of the program's efforts.
As a major part of the effort to disseminate the results of its research, PPRB has
produced this compilation of case studies. These studies are the culmination of some of
the major current research efforts being conducted in the area of pollution prevention. It
is a compilation of summaries of pollution prevention demonstrations, assessments and
research projects conducted within the Branch. We hope that this compendium will
facilitate the development and adoption of pollution prevention techniques throughout
the United States and other countries.
IV
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CONTENTS
Foreword iii
Abstract iv
Personnel Roster vii
Acknowledgements viii
Introduction 1
Section 1 Waste Reduction Innovative Technology Evaluation Program (WRITE)
Overview 2
Computerized Printed Circuit Board Plating System 4
Computerized Sulfuric Acid Anodizing System 7
Robotic Paint Facility 10
Plastic Bead-Blast Paint Stripper 13
Freon Recovery 15
Nickel Plating Bath Solution Recovery 18
Chemical Substitution for Trichloroethane and Methanol 20
Section 2 Waste Reduction Evaluations At Federal Sites Program (WREAFS)
Overview 22
Scott Air Force Base 24
Fitzsimmons Army Medical Center 27
Fort Riley 30
Hospital Pollution Prevention Case Study 33
Air Force Plant 6 36
Section 3 Waste Minimization Assessments Program
Overview 38
Nuclear Powered Electrical Generating Station 39
Manufacturer of Finished Leather 42
Local School District 45
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Department of Transportation Maintenance Facility 48
Printer of Forms and Supplies for the Legal Profession 51
Section 4 University-Based Assessments Program
Overview 54
Manufacturer of Printed Circuit Boards 56
Manufacturer of Chemicals 59
Dairy 62
Manufacturer of Heating, Ventilating, & Air Conditioning Units 65
Manufacturer of Automotive A/C Condensers & Evaporators 68
Manufacturer of Components for Automobile Air Conditioners 71
Refurbishing Railcars, Wheel Sets, and Air Brakes 74
Manufacturer of Permanent-Magnet DC Electric Motors 77
Manufacturer of Metal Bands, Clamps, Retainers, and Tooling 80
Manufacturer of Aluminum Extrusions 83
Manufacturer of Aluminum Cans 86
Manufacturer of Treated Wood Products 88
Manufacturer of Military Furniture 90
Manufacturer of Commercial Ice Machines & Ice Storage Bins 92
Index 95
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Personnel Roster
POLLUTION PREVENTION RESEARCH BRANCH
MAILING ADDRESS: U.S. Environmental Protection Agency
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
FAX: (513) 569-7549 AREA CODE: (513)
Bender, Rita 569-7727
Bridges, James S 569-7683
Brown, Lisa M 569-7634
Corn, Ruth E 569-7215
Curran, Mary Ann 569-7837
Freeman, Harry M 569-7529
George, Emma Lou 569-7578
Harten, Teresa M 569-7565
Howell, S. Garry 569-7756
Licis, Ivars J 569-7718
Randall, Paul M 569-7673
Robertson, Anne 569-7658
Springer, Johnny 569-7542
Stephan, David G 569-78%
Stone, Kenneth R 569-7474
VII
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ACKNOWLEDGEMENTS
This report was prepared by Mr. Johnny Springer, Jr., EPA's Project Officer in
the Pollution Prevention Research Branch of the Risk Reduction Engineering
Laboratory, Cincinnati, Ohio. Appreciation is given to the large number of contributors
to this report. Contributions were made by USEPA's Office of Research and
Development, various Federal Departments, state pollution prevention and research
organizations, and members of industry.
Some draft information used for this report was edited by Mrs. Marion Curry for
the U.S. Environmental Protection Agency under Contract No. 9-C8-031-TNSE, for
EPA's Office of Research and Development.
Vlll
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INTRODUCTION
As a major part of the effort to disseminate the results of its research, the
Pollution Prevention Research Branch has produced this compilation of case studies.
These studies are the culmination of some of the major current research efforts being
conducted in the area of pollution prevention. It is a compilation of summaries of
pollution prevention demonstrations, assessments and research projects conducted within
the Branch.
The compendium is separated into four sections, featuring four of the Branch's
key programs. The Waste Reduction Innovative Technology Evaluation (WRITE)
Program is a technology demonstration program conducted in cooperation with sk states
and one local government. The focus of the research is to perform technical and
economic evaluations of pollution prevention technologies. The Waste Reduction
Evaluations at Federal Sites (WREAFS) Program focuses on performing waste
minimization assessments at various Federal facilities. The Waste Minimization
Assessments Program is designed to focus on the evaluation of the use of waste
minimization assessments in hazardous waste generating facilities in New Jersey. The
University-Based Assessments Program targets small and medium-sized businesses in its
assessment program. This program utilizes Waste Minimization Assessment Centers in
Colorado, Kentucky and Tennessee to conduct waste minimization assessments for
businesses which lack pollution prevention expertise. All three assessment programs
follow the procedures outlined in the EPA Waste Minimization Opportunity Assessment
Manual (EPA/625/7-88/003, July 1988)
An overview of each program is provided at the beginning of each section of the
compendium. The case studies are cross referenced according to key words in an index
at the end of the compendium. The Pollution Prevention Research Branch personnel
roster is listed on page vii to facilitate contacting the EPA Project Officer. Information is
also provided on availability of full reports and the EPA Project Officer who conducted
the research. Case studies of individual EPA project summaries and environmental
research briefs which have EPA document numbers (EPA/xxx/xxx/xxx) are available from
EPA's Center for Environmental Research Information (CERI): U.S. Environmental
Protection Agency, Center for Environmental Research Information, 26 W. Martin
Luther King Drive, Cincinnati, Ohio 45268. Information on obtaining project summaries
for other reports is available by contacting the EPA Project Officer referenced.
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WASTE REDUCTION INNOVATIVE TECHNOLOGY EVALUATION PROGRAM
(WRITE)
The Waste Reduction Innovative Technology Evaluation (WRITE) Program is a
research demonstration program designed to evaluate the use of innovative engineering
and scientific technologies to reduce the volume and/or toxicity of wastes produced from
the manufacture, processing, and use of materials. It encourages the interaction of
government and industry in the demonstration and evaluation of available innovative
production and recycling options for reducing waste generation.
The objectives of the WRITE Program are:
(1) To establish reliable performance and cost information on pollution
prevention techniques by conducting evaluations or demonstrations of the
more promising innovative technologies.
(2) To accomplish an early introduction of waste reduction techniques into
broad commercial practice.
(3) To encourage active participation of small and medium-sized companies in
evaluating and adopting pollution prevention concepts by providing support
to these companies through State and local government agencies.
(4) To encourage the transfer of knowledge and technology concerning
pollution prevention practices between large, medium-sized, and small
industries.
(5) To provide solutions to important chemical-, wastestream-, and industry-
specific pollution prevention research needs.
Under the WRITE Program, EPA and seven cooperating state and county
governments (California, Connecticut, Illinois, Minnesota, New Jersey, Washington, and
Erie County, New York) evaluate and demonstrate the engineering and economic
feasibility of selected waste reducing technologies in a manufacturing or fully operational
setting.
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Research efforts under the WRITE Program focus primarily on source reduction
and the recycling and reuse of waste materials. The WRITE Program has completed,
ongoing and/or future technology evaluations in the areas of: printed circuit board
plating, paint mixing/stripping, plating solution recovery, water-based inks as substitutes
for solvent based inks, alternative oil filtration systems for diesel engines, acetone
recovery, cutting fluid recycling, biodegradable solvents, CFC replacement/recovery,
vacuum distillation, ion exchange, ultrafiltration and others.
EPA acknowledges and appreciates the cooperation of the following organizations
in the administration of the WRITE Program:
California: California Department of Health Services (DHS)
Connecticut: Connecticut Hazardous Waste Management Service (CHWMS)
Illinois: Illinois Hazardous Waste Research and Information Center
(IHWRIC)
Minnesota: Minnesota Technical Assistance Program (MnTAP)
New Jersey: New Jersey Department of Environmental Protection (NJDEP)
Washington: Washington Department of Ecology
Erie County, New York: Erie County Department of Environment and Planning,
Division of Environmental Compliance Services
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COMPUTERIZED PRINTED CIRCUIT BOARD PLATING SYSTEM
INTRODUCTION
This study was technically and economically evaluated under the California/EPA
Waste Reduction Innovative Technology Evaluation (WRITE) Program, and was a
cooperative effort between EPA's Risk Reduction Engineering Laboratory (RREL), the
California Department of Health Services (DHS), and General Dynamics Pomona
Division (Pomona).
General Dynamics Pomona Division builds various tactical defense weapons,
primarily air defense missiles, and gun systems. In 1984, General Dynamics established a
corporate environmental program with individual Division responsibility for hazardous
waste reduction, including reductions in the use of toxic substances.
As a result of implementation of this corporate policy, several waste reduction
process modifications have been instituted at the Pomona Division. A reduction of 97
percent in the annual discharge of hazardous (about 10,600 tons), liquid, and solid
wastes, and a reduction of 95 percent in volatile organic contaminant (VOC) emissions
(about 17.5 tons) have been reported by Pomona through a combination of waste
reduction and treatment technologies.
WRITE METHODOLOGY
The waste minimization technology employed at Pomona was screened for
technology applicability, source reduction potential, extent of process modification, and
cost-effectiveness. The Worth Assessment Model used was developed by EPA specifically
for the WRITE Program. As a result of applying the model, the computerized printed
circuit board plating system was chosen for further analysis.
The technical and economic evaluation was conducted during site visits, and
additional information required was obtained through subsequent follow-up conversations
with Pomona staff and system suppliers. As economic objectives were centered around
return on capital, internal rate of return, and payback periods which are considered
company sensitive information, a simple payback for each process was calculated.
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TECHNOLOGY DESCRIPTION AND EVALUATION
Chemcut Corporation installed a new computerized printed circuit board plating
system at General Dynamics in July of 1988, at a cost of $4,100,000. This new plating
system completely eliminated rinse tanks from the process by use of a unique spray-rinse
configuration contained in a transporter hoist system that passes over the plating bath
tanks. This computerized hoist system allows the circuit boards to be rinsed for only a
short duration after their immersion in a process solution. Rinse water discharge from
this new process is less than 10 gallons per minute (gpm) versus 60 gpm from the old
process. This reduction in wastewater discharge allowed for a corresponding reduction in
metal recovery system sizing. The use of spray rinse versus a dip rinse can also be a
major design factor if water supply limitations must be considered or if space is limited in
locating the plating line.
Copper spheres in anode baskets are also used in the new system instead of a
conventional anode bar-and-hook system that was utilized in the old plating system. This
allows a 1:1 ratio of anode to cathode for a very even plating across the panel and
through the holes.
In conjunction with the installation of the new production equipment, Chemcut
Corporation was required to provide a non-sludge-producing treatment system for all
waste streams generated by the process. This resulted in the installation of a new
copper-recovery system using short-bed ion exchange columns and electrowinning
technologies. This system now produces salable scrap copper metal, eliminating a major
waste stream to the conventional sludge-producing waste treatment system.
Cost savings in labor and waste treatment were found to be the major cost
parameters, resulting in a favorable net annual operating savings between the original
and newly installed printed circuit board plating systems. The payback period for the new
system was estimated to be 8.3 years. Annual cost savings of $130,000 in waste treatment
and disposal were determined from the recovery of copper from rinse water and process
tank solutions, which were previously treated and disposed as a hazardous sludge. An
annual cost savings for water usage was estimated to be $10,000 based on a net overall
decrease in rinse-water discharges of 50 gpm.
Report Title: Evaluations of Waste Minimization Technologies at the General Dynamics
Pomona Division
Report Availability: Immediate
EPA Project Officer: Lisa M. Brown
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Key Words: tactical defense weapons; computerized printed circuit board plating
system; eliminated rinse tanks; copper-recovery system; ion exchange;
electrowinning
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COMPUTERIZED SULFURIC ACID ANODIZING SYSTEM
INTRODUCTION
This study was technically and economically evaluated under the California/EPA
Waste Reduction Innovative Technology Evaluation (WRITE) Program, and was a
cooperative effort between EPA's Risk Reduction Engineering Laboratory (RREL), the
California Department of Health Services (DHS), and General Dynamics Pomona
Division (Pomona).
General Dynamics Pomona Division builds various tactical defense weapons,
primarily air defense missiles, and gun systems. In 1984, General Dynamics established a
corporate environmental program with individual Division responsibility for hazardous
waste reduction, including reductions in the use of toxic substances.
As a result of implementation of this corporate policy, several waste reduction
process modifications have been instituted at the Pomona Division. A reduction of 97
percent in the annual discharge of hazardous (about 10,600 tons), liquid, and solid
wastes, and a reduction of 95 percent in volatile organic contaminant (VOC) emissions
(about 17.5 tons) have been reported by Pomona through a combination of waste
reduction and treatment technologies.
WRITE METHODOLOGY
The waste minimization technology employed at Pomona was screened for
technology applicability, source reduction potential, extent of process modification, and
cost-effectiveness. The Worth Assessment Model used was developed by EPA specifically
for the WRITE Program. As a result of applying the model, the computerized sulfuric
acid anodizing system was chosen for further analysis.
The technical and economic evaluation was conducted during site visits, and
additional information required was obtained through subsequent follow-up conversations
with Pomona staff and system suppliers. As economic objectives were centered around
return on capital, internal rate of return, and payback periods which are considered
company sensitive information, a simple payback for each process was calculated.
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TECHNOLOGY DESCRIPTION AND EVALUATION
In December 1988, General Dynamics replaced its 35 year old chromic acid
aluminum anodizing system with a new computerized sulfuric acid anodizing system
which utilized computerized hoists and on-demand rinsing. The new system, supplied by
NAPCO, Inc., enabled General Dynamics to eliminate a major source of chromium
emissions.
General Dynamics used chromic acid in the original aluminum anodizing process
due to military contract specifications. Typically, the much less corrosive chromic acid is
used when parts are either subject to stress or contain blind holes (e.g.. trapped areas,
recesses, porous castings) in which anodizing solution could be entrapped. Chromic acid
is also used for detection of fine surface flaws on finished parts. This process, in spite of
its higher operating costs, is used by the aerospace industry, the military, and military
contractors.
General Dynamic's motivation for converting to a sulfuric acid anodizing system
was that its original chromic acid system could not be modified cost-effectively to meet
production requirements and maintain compliance with current and anticipated air and
water regulatory requirements. Besides the chemical substitution to eliminate chromium
releases, the addition of automated hoists and the on-demand water bath rinse system
helped to reduce wastewater treatment requirements. This system reduces treatment
requirements by avoiding unnecessary drag-out of immersion fluids and by reducing rinse
water usage and wastewater treatment requirements by reducing water consumption and
by monitoring the conductivity of the rinse water in the tank. By using this on-demand
water process, rinse water requirements were reduced from approximately 15-20 gallons
per minute (gpm) to approximately 6-8 gpm.
The capital cost of the new sulfuric acid anodizing system was $955,000 and
included the computerized hoist and on-demand anodizing rinse systems. The operating
and maintenance costs were lower for the new system when compared to the old chromic
acid system because it is less energy intensive, it has a smaller plating interval, and
wastewater treatment costs are less. Because sulfuric acid is much more conductive as an
electrolyte, the anodizing process requires less power. The cost savings for electricity
were estimated to be $10,900, based on an annual decrease in electrical consumption.
The sulfuric acid process is also much faster than chromic acid, thus resulting in less
process time required for a given film thickness. This results in lower operating costs due
to increased through-put potential.
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Wastewater treatment costs are less for the new system due to a decrease in
metals removal requirements. The sulfuric acid process requires only aluminum reduction
resulting in a nonhazardous sludge as compared to aluminum and chromium reduction in
a chromic acid system which requires additional tanks and chemicals for treatment and
settling. The disposal costs for the aluminum sludges generated from the sulfuric acid
process are less than the hazardous chromium and aluminum sludge generated from the
chromic acid process.
Additional cost savings are realized with the addition of computerized hoists and
on-demand spray rinse systems. Both of these systems have reduced labor requirements;
water consumption has been reduced from 20 to 8 gpm. The cost savings in reduced
water consumption has been estimated to be $2,300 annually. General Dynamics also
expects that the computerized hoist system will lower costs associated with rejects and
rework.
Report Title: Evaluation of Waste Minimization Technologies at the General Dynamics
Pomona Division Plant
Report Availability: Immediate
EPA Project Officer: Lisa M. Brown
Key Words: tactical defense weapons; computerized sulfuric acid anodizing system;
computerized hoists; on-demand rinsing; chromium; chemical substitution;
water consumption
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ROBOTIC PAINT FACILITY
INTRODUCTION
This study was technically and economically evaluated under the California/EPA
Waste Reduction Innovative Technology Evaluation (WRITE) Program, and was a
cooperative effort between EPA's Risk Reduction Engineering Laboratory (RREL), the
California Department of Health Services (DHS), and General Dynamics Pomona
Division (Pomona).
General Dynamics Pomona Division builds various tactical defense weapons,
primarily air defense missiles, and gun systems. In 1984, General Dynamics established a
corporate environmental program with individual Division responsibility for hazardous
waste reduction, including reductions in the use of toxic substances.
As a result of implementation of this corporate policy, several waste reduction
process modifications have been instituted at the Pomona Division. A reduction of 97
percent in the annual discharge of hazardous (about 10,600 tons), liquid, and solid
wastes, and a reduction of 95 percent in volatile organic contaminant (VOC) emissions
(about 17.5 tons) have been reported by Pomona through a combination of waste
reduction and treatment technologies.
WRITE METHODOLOGY
The waste minimization technology employed at Pomona was screened for
technology applicability, source reduction potential, extent of process modification, and
cost-effectiveness. The Worth Assessment Model used was developed by EPA specifically
for the WRITE Program. As a result of applying the model, the robotic paint facility was
chosen for further analysis.
The technical and economic evaluation was conducted during site visits, and
additional information required was obtained through subsequent follow-up conversations
with Pomona staff and system suppliers. As economic objectives were centered around
return on capital, internal rate of return, and payback periods which are considered
company sensitive information, a simple payback for each process was calculated.
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TECHNOLOGY DESCRIPTION AND EVALUATION
The General Dynamics paint production operations facility was completed in
December 1988 to replace manual mixing and hand spraying of metal parts in naval
weapons systems. It includes computer-controlled robots (a GRI OM 5000 Unit) which
allows quick, automated precision painting. A proportional paint mixer was also added,
which feeds preselected quantities of individual paint components directly to a paint
spray nozzle thus eliminating batch makeup operations. Electrostatic spray guns and
automatic waste cleaning solvent collection systems were also introduced to allow for
recycle and reuse of waste paint. Spray paint booths are also available for touch-ups.
Stills are used for recycling paint cleaning solvents.
The painting facility uses both oil- and water-based paints. For oil-based paints,
polyurethane thinner is used for paint thinning and equipment cleaning. A thinner
containing isopropyl alcohol and xylene is used with water-based paint. Paint waste was
reduced from 42 tons in 1987 to 31 tons in 1988, and were further reduced to 17 tons in
1989. About 1,000 gallons of polyurethane cleaning solvent per year is now being recycled
through the paint shop solvent stills, resulting in approximately 60 to 100 pounds of still
bottoms per week, or about 5,000 pounds per year. The still bottoms and waste paint are
sent off site for incineration.
Paint purchases decreased from 6,530 gallons in 1988 to 5,230 in 1989; solvent
purchases decreased from 2,500 gallons in 1988 to 1,080 gallons in 1989. These decreases
are mainly due to changes in equipment and operating purchases in the paint shop, but
also partially due to changes in inventory and decrease in production rates.
Only polyurethane solvent (for oil-based paints) is currently being recycled in the
stills. When distilling the water-based paint solvent, which contains isopropyl alcohol and
xylene, the recycled solvent separates into two layers, a water and a solvent layer. Even
when the water is removed by draining, water contained within the solvent prevents the
solvent from being reused for thinning and cleaning. Potentially, the water can be
removed by adding a water separator upstream and a molecular sieve downstream of the
stills.
The installation cost of the robotic painting system was $1,400,000. The system
included a parts conveyor, computer-controlled robots, electrostatic spray guns,
proportional paint mixing, and cleaning solvent collection equipment. The Disposal of 42
tons of waste in 1987 would have cost about $73,000 at the current disposal rates of $420
per drum, plus $7,000 per truckload for transportation (80 drums). The disposal costs of
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21 tons in 1989 would be about $36,000. The payback period from a waste disposal
standpoint alone would be 40 years. This substantially overstates the payback period,
however, because the savings in labor costs from painting and waste disposal and any
decrease in rejects in parts were not included, as it was considered company sensitive
information. Payback for the solvent stills is only about 4 years, but would be less if all
cleaning solvent were being recycled.
Report Title: Evaluation of Waste Minimization Technologies at the General
Dynamics Pomona Division Plant
Report Availability: Immediate
EPA Project Officer: Lisa M. Brown
Key Words: paint production operations; naval weapons systems; computer-controlled
robots; proportional paint mixer; electrostatic spray guns; isopropyl alcohol;
xylene; polyurethane solvent; distillation; molecular sieve
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PLASTIC BEAD-BLAST PAINT STRIPPER
INTRODUCTION
This study was technically and economically evaluated under the California/EPA
Waste Reduction Innovative Technology Evaluation (WRITE) Program, and was a
cooperative effort between EPA's Risk Reduction Engineering Laboratory (RREL), the
California Department of Health Services (DHS), and General Dynamics Pomona
Division (Pomona).
General Dynamics Pomona Division builds various tactical defense weapons,
primarily air defense missiles, and gun systems. In 1984, General Dynamics established a
corporate environmental program with individual Division responsibility for hazardous
waste reduction, including reductions in the use of toxic substances.
As a result of implementation of this corporate policy, several waste reduction
process modifications have been instituted at the Pomona Division. A reduction of 97
percent in the annual discharge of hazardous (about 10,600 tons), liquid, and solid
wastes, and a reduction of 95 percent in volatile organic contaminant (VOC) emissions
(about 17.5 tons) have been reported by Pomona through a combination of waste
reduction and treatment technologies.
WRITE METHODOLOGY
The waste minimization technology employed at Pomona was screened for
technology applicability, source reduction potential, extent of process modification, and
cost-effectiveness. The Worth Assessment Model used was developed by EPA specifically
for the WRITE Program. As a result of applying the model, the plastic bead-blast paint
stripper system was chosen for further analysis.
The technical and economic evaluation was conducted during site visits, and
additional information required was obtained through subsequent follow-up conversations
with Pomona staff and system suppliers. As economic objectives were centered around
return on capital, internal rate of return, and payback periods which are considered
company sensitive information, a simple payback for each process was calculated.
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TECHNOLOGY DESCRIPTION AND EVALUATION
The plastic bead-blast paint stripper at General Dynamics was installed in June
1988, to replace methylene chloride stripping. Reusable plastic beads or media are used
in this mechanical stripping operation, which is similar to sand blasting. Paint is stripped
from the hangers used to hold parts being painted in the paint shop and from parts
having paint defects.
The plastic bead-blasting booth is a Pauli and Griffin Pram Machine
approximately 3 cubic feet and uses size 20 to 30 mesh Poly Plus beads. The unit is used
only on an as-needed basis, generally a few hours per week.
Waste generated during the operation of the plastic-bead blasting unit consists
primarily of paint chips with a small amount of spent plastic beads which is sent off site
for incineration. Stripping by methylene chloride resulted in about 10,000 pounds per
year of toxic solvent contaminated with paint sludge, which was also sent off site for
incineration. The bead-blast paint stripper was installed at a cost of $18,000. This system
eliminated the disposal of about 10,000 Ib/year with a cost of approximately $10,000.
Both the methylene chloride and bead-blast waste are disposed by incineration resulting
in waste disposal costs of $10,000 for methylene chloride and $5,000 for bead-blast waste.
A cost savings of $5,000 for disposal of paint chips and spent plastic beads was realized
when compared to methylene chloride disposal and the capital cost of the unit. The
payback period from a waste disposal perspective is about 3.6 years. This does not
consider differences in operator time, maintenance requirements, and stripping materials
which will vary depending on parts being stripped, whether methylene chloride stripping
is being done by spray-on or dip tank methods, skill of operator, and recovery of
stripping material.
Report Title: Evaluation of Waste Minimization Technologies at the General Dynamics
Pomona Division Plant
Report Availability: Immediate
EPA Project Officer: Lisa M. Brown
Key Words: tactical defense weapons; robotic paint facility; plastic bead-blast paint
stripper; methylene chloride stripping; incineration; paint chips
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FREON RECOVERY STILLS
INTRODUCTION
This study was technically and economically evaluated under the California/EPA
Waste Reduction Innovative Technology Evaluation (WRITE) Program, and was a
cooperative effort between EPA's Risk Reduction Engineering Laboratory (RREL), the
California Department of Health Services (DHS), and General Dynamics Pomona
Division (Pomona).
General Dynamics Pomona Division builds various tactical defense weapons,
primarily air defense missiles, and gun systems. In 1984, General Dynamics established a
corporate environmental program with individual Division responsibility for hazardous
waste reduction, including reductions in the use of toxic substances.
As a result of implementation of this corporate policy, several waste reduction
process modifications have been instituted at the Pomona Division. A reduction of 97
percent in the annual discharge of hazardous (about 10,600 tons), liquid, and solid
wastes, and a reduction of 95 percent in volatile organic contaminant (VOC) emissions
(about 17.5 tons) have been reported by Pomona through a combination of waste
reduction and treatment technologies.
WRITE METHODOLOGY
The waste minimization technology employed at Pomona was screened for
technology applicability, source reduction potential, extent of process modification, and
cost-effectiveness. The Worth Assessment Model used was developed by EPA specifically
for the WRITE Program. As a result of applying the model, the freon recovery system
was chosen for further analysis.
The technical and economic evaluation was conducted during site visits, and
additional information required was obtained through subsequent follow-up conversations
with Pomona staff and system suppliers. As economic objectives were centered around
return on capital, internal rate of return, and payback periods which are considered
company sensitive information, a simple payback for each process was calculated.
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TECHNOLOGY DESCRIPTION AND EVALUATION
Three Freon recovery stills manufactured by Recyclene were installed in
December 1988, to collect and distill waste from solvent degreasing operations
throughout Pomona at a cost of $240,000, plus $40,000 for add-on equipment to address
operating problems. Recovered solvent is tested and reformulated under a quality
assurance program to ensure that all the manufacturer's specifications are met before
returning it to material stores for reissue to production operations. Still bottoms are dried
in the distillation process and sent off site for incineration.
Prior to the installation of these stills, a single Freon recovery still was installed in
November 1985, to extend the life of Freon used in conveyorized cleaners. This extended
the solvent change out period to once per year, and saved 35,000 Ib annually in Freon
purchases.
Testing of the Freon recovery stills in 1988 indicated that the distillation process
was working, but that the Freon being recycled was contaminated with water, which
degraded the quality of the recovery product. The Pomona Division has installed
separators to remove water and molecular sieves to further dry the Freon after
distillation. The additions to each still cost $13,000, plus installation, but allow the Freon
recovery to be operated as planned to produce a quality recycled solvent.
Reduction in Freon purchases through 1988 have primarily come through
improved operations' procedures such as extended change out times for Freon, and
reduction in evaporative losses. A baseline of 421,000 pounds of Freon for 1988 was used
to calculate reductions in Freon usage attributable to the use of the three Freon stills,
which are assumed to be utilized at full capacity for the first time in 1989. The capital
cost of the stills was $270,000 with annual operating costs considered negligible. The
amount of Freon recycled or the amount of avoided purchases were 212,473 Ib, which at
$1.64 per Ib, was $384,456. The cost to incinerate 11,183 pounds of still bottoms was
$8,000 with a cost savings from avoided Freon disposal equal to $148,583. The total cost
savings were $489,039 with a payback period of 0.55 years. This is a minimum payback
number based on recycling all of the Freon that is not lost through evaporation and
drag-out losses.
Report Title: Evaluation of Waste Minimization Technologies at the General Dynamics
Pomona Division Plant
Report Availability: Immediate
EPA Project Officer: Lisa M. Brown
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Key Words: tactical defense weapons; freon recovery; solvent degreasing; distillation;
conveyorized cleaners; separator; molecular sieve
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AN ADVANCED REVERSE OSMOSIS SYSTEM FOR
NICKEL PLATING BATH SOLUTION RECOVERY
INTRODUCTION
This study was performed under the California/EPA WRITE program, and was a
cooperative effort between EPA's Pollution Prevention Research Branch, under the
Office of Research and Development, the Alternative Technology Division of the Toxic
Substances Control Program within the Department of Health Services (DHS) of the
State of California, Hewlett-Packard (HP), and Water Technologies, Inc. (WTI). Science
Applications International Corporation (SAIC) provided technical support on this
WRITE project.
The effectiveness of an Advanced Reverse Osmosis System (AROS) in the
recovery of nickel plating bath solution and rinse water was evaluated and the costs were
compared with that of an existing chemical precipitation treatment system at the Hewlett-
Packard Facility in Sunnyvale, California. HP's existing wastewater treatment system for
plating wastes involves precipitation of metals as hydroxide salts.
The AROS is a reverse osmosis (RO) unit with specially adapted membranes that
do not require pH adjustments to neutral. The unit includes a microprocessor control to
manage the RO membranes, and a continuous monitoring system that monitors the
influent, permeate, and concentrate for temperature, flow rate, and conductivity.
The RO membranes clean rinses to pre-specified standards and concentrate
plating salts, in order to recycle both rinse water and plating salts. An AROS can
reconcentrate dilute solutions to at or near bath strength (typically a concentration of
40% to 70%) without evaporation or additional concentration technology.
TECHNICAL ANALYSIS
HP tested the AROS on a nickel plating system consisting of two plating baths
followed by a "dirty" rinse tank and then a "clean" rinse tank. The rinse water flows
countercurrent to the flow of the items being plated. Four liquid streams of the AROS
unit were sampled on October 17, 1990 to obtain a one day snapshot of the system's
operation. Removal efficiencies obtained based on the actual data were used to prepare
a technical evaluation of the system. Sample analysis included nickel, chloride, sulfates,
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pH, total dissolved solids, conductivity, color, and total organic carbon. The AROS unit
produced a composite permeate that was satisfactory as clean rinse water makeup, its
intended purpose. Similarly, the concentrate was of quality (40% to 50% plating bath
concentration) that could be used as nickel plating bath solution makeup.
ECONOMIC ANALYSIS
Economic analysis is based on data obtained from Hewlett-Packard. At HP, the
AROS unit only treated a small fraction, e.g. about 3% of the total plating wastewater
flow. HP estimates that the net annual savings from use of the AROS unit would be
approximately $17,100/yr. THe AROS unit costs approximately $75,000, which
represents approximately $63,000 for the AROS unit plus another $12,000 for permanent
installation and training of operating personnel. The payback period is 4.4 years.
CONCLUSIONS
The AROS unit performance was considered excellent. The Hewlett-Packard
evaluation showed an estimated net annual savings of approximately $17,000/year through
use of the AROS unit. Under company policy this savings was insufficient to justify the
capital expenditure of approximately $75,000. Hewlett-Packard decided not to purchase
the AROS unit.
Because the AROS unit treated a small increment of the wastewater flow at HP,
it was difficult for the AROS unit to be cost effective; however, in a different setting, the
AROS unit might be very cost effective.
Report Title: The Evaluation of an Advanced Reverse Osmosis System at the Sunnyvale,
California Hewlett Packard Facility
Report Availability: Immediate
EPA Project Officer: Lisa M. Brown
Key Words: reverse osmosis; nickel plating bath solution recovery; chemical
precipitation; hydroxide salts; microprocessor control; continuous
monitoring
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CHEMICAL SUBSTITUTION FOR 1,1,1-TRICHLOROETHANE AND METHANOL
IN AN INDUSTRIAL CLEANING OPERATION
INTRODUCTION
EPA's Pollution Prevention Research Branch in the Office of Research and
Development along with APS Materials, Inc. (APS), a small metal finishing company in
Dayton, Ohio, participated in a joint research project to evaluate the substitution of a
dilute, terpene-based cleaner for 1,1,1-trichloroethane (TCA) and methanol in their
degreasing operations. TCA is used as a cold solvent degreasing agent in many industrial
degreasing processes. APS generates TCA and methanol waste from their plasma spray
deposition process operations. Waste TCA and methanol were being generated at the
rate of 1/2 barrel each per month. Disposal of these solvents had become increasingly
difficult.
BACKGROUND
APS plasma sprays parts for aircraft engines, orthopedic implants, and other
applications. In their biomedical parts division, APS primarily coats cobalt/molybdenum
parts and titanium parts with a titanium alloy. To achieve a strong, adhesive coating, the
cobalt/molybdenum parts and titanium parts were cleaned with TCA and methanol
respectively. After first passing through a series of preparatory steps, the part was then
immersed in a pail containing TCA or methanol. The pail was placed in an ultrasonic
bath containing warm water for 15 minutes. Contaminants from previous cleaning steps
are removed in this cleaning process. The part then continues on through the finishing
process.
TECHNICAL ANALYSIS
The focal point of this project was to replace TCA and methanol with the dilute
terpene-based cleaner. To accomplish this, some equipment modifications were made.
A heater was added to the old ultrasound bath. A deionized water system was purchased
along with a stainless steel bath and immersion heater. A heat gun was purchased to
quicken the drying process. Other than these equipment additions, the cleaning
procedure remained unchanged.
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The purpose of the sampling and analysis project at APS was to support a
qualitative judgement of the cleaning capabilities of the substitute cleaning solution. The
sampling and analysis protocol was set up in three phases. The first two phases
investigated the proficiency of the cleaning solvents. Analyses revealed that the dilute
limonene solution adequately removed contaminants and no residual limonene was
detected on the parts.
The third phase of the analysis examined the quality of the coating bond for parts
cleaned with the terpene based solution. The before and after tensile strength results
were comparable. Overall, the bonding strengths were actually slightly better for the
dilute limonene cleaner.
ECONOMIC ANALYSIS
Although the new cleaning system used the same cleaning method, some capital
expenditures were needed to alter the process. Capital cost included purchasing of the
ultrasound with heater, 5 gal. stainless steel rinse vessel, immersion heater, heat gun, and
installation of a deionized water system. The capital cost totalled $1793. The net annual
cost savings for the project was $4800/yr. with a payback period of 4.5 months.
CONCLUSIONS
In summary, a terpene-based cleaner can adequately clean metal parts without
adversely affecting the performance of the plasma-arc coating application. APS has
deployed the water-based cleaner in all operations where specifications do not dictate the
use of TCA or methanol. APS is also currently performing studies to determine the
optimal life of the cleaner in order to minimize cleaner use. Elimination of the disposal
problems, maintenance of plasma-arc coating quality, annual cost savings and the short
payback period make the use of terpene-based cleaners attractive to other metal
cleaning/coating operations.
Report Title: Chemical Substitution for 1,1,1-Trichloroethane and Methanol in an
Industrial Cleaning Operation
Report Availability: Immediate
EPA Project Officer: Lisa Brown/Johnny Springer
Key Words: terpene-based cleaner; 1,1,1-trichloroethane; methanol; cold solvent
degreasing; plasma spray deposition; aircraft engines; orthopedic implants;
cobalt/molybdenum parts; titanium parts; ultrasonic bath; deionized water
system; cleaning capabilities; limonene; coating bond
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WASTE REDUCTION EVALUATIONS AT FEDERAL SITES PROGRAM
(WREAFS)
The Waste Reduction Evaluations at Federal Sites (WREAFS) Program consists
of a series of demonstration and evaluation projects for waste reduction conducted
cooperatively by the U.S. Environmental Protection Agency (EPA) and various parts of
the Department of Defense, Department of Energy, and other Federal agencies. The
WREAFS Program focuses on waste minimization research opportunities and technical
assessments at Federal sites. The objectives of the WREAFS Program include: (1)
conducting waste minimization workshops; (2) performing waste minimization
opportunity assessments; (3) demonstrating waste minimization techniques or
technologies at Federal facilities; and (4) enhancing waste minimization benefits within
the Federal community.
The WREAFS Program facilitates the adoption of pollution prevention/waste
minimization practices through technology transfer. New techniques and technologies for
reducing waste generation are identified through waste minimization opportunity
assessments and may be further evaluated through joint research, development, and
demonstration projects. The waste minimization opportunity assessments follow the
procedures outlined in the EPA Waste Minimization Opportunity Assessment Manual
(EPA/625/7-88/003, July 1988). The major phases of a WREAFS assessment are:
(1) Planning and Organization: organization goal setting;
(2) Assessment: careful review of a facility's operations and wastestreams and
the identification and screening of potential options to minimize waste;
(3) Feasibility Analysis: evaluation of the technical and economic feasibility of
the options selected and subsequent ranking of options; and
(4) Implementation: procurement, installation, implementation, and evaluation
(at the discretion of the facility surveyed)
In Fiscal Year 1992, the WREAFS program will focus on providing technical
research support to the Tidewater Interagency Pollution Prevention Program (TIPPP).
The concept of TIPPP is to take advantage of the capabilities of well-defined
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communities to develop an integrated multi-media pollution prevention plan that includes
both short- and long-term projects with results that are transferable to other
communities. TIPPP will sponsor a number of joint EPA/DoD/NASA community R&D
projects that require demonstration before being accepted within the public and private
sectors. For WREAFS, the TIPPP effort is the next logical step towards the ultimate
goal of establishing an overall Federal Cooperative on pollution prevention.
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SCOTT AIR FORCE BASE
INTRODUCTION
As part of the WREAFS program, a waste minimization assessment of Scott Air
Force Base has been conducted. The base is part of the Military Airlift Command
(MAC), and operates and maintains a fleet of C-9 medical aircraft. The assessment
focuses on the non-destructive wheel inspection process. Non-destructive inspection
(NDI) was of special interest to EPA because of the widespread use in the military and
commercial airlines. In addition, assessments of the paint stripping/parts cleaning and
printed circuit board manufacture were carried out.
EXISTING WASTE MANAGEMENT ACTIVITIES
Non-destructive Inspection (NDI)
As part of the preventative maintenance practices on the C-9 aircraft, landing
wheels are inspected for signs of fatigue with a liquid dye penetrant method used at Scott
AFB. The primary wastes produced by this method are penetrant, emulsifier, and
developer. Waste penetrant is drummed and picked up by a waste handler for
incineration in a cement kiln. The Defense Reutilization and Marketing Office (DRMO)
currently classifies the penetrant waste as a RCRA D001 waste. The 100-gal batch of
emulsifier is changed out about every six months and sent to the sewage treatment plant.
Developer batches of approximately 100 gal are changed out on about the same
frequency as the emulsifier batches. Like the emulsifier, the developer is sent to the
sewage treatment plant. Due to the levels of sodium chromate present, the batches meet
the criteria for a RCRA D007 waste.
Painting/Paint Removal/Parts Cleaning
The paint shop handles all aerospace ground equipment (AGE) for Scott AFB.
Paint booths are normally used. Approximately 24 one-gal kits of polyurethane paint are
used each year. About 90% of the paint used at the paint shop is polyurethane. The
wastes generated by painting are overspray solids, booth compound, booth wastewater,
waste paint and thinner, and volatile organic compounds (VOCs). About 220 gal of
sludge and scum are placed in 55-gal drums and hauled away each year to the
appropriate facility. Booths are periodically coated with a protective film called booth
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compound to prevent adhesion to the metal walls. As the compound deteriorates, a new
coating is then applied and the old compound is discarded in a sanitary landfill. The
booth water is drained to the sewage treatment plant. Paint thinner is used to clean
paint gun nozzles. The mixed thinner and paint, along with unused paint, are placed in
30-gal drums for disposal by Safety-Kleen, Inc. VOCs are released during atomization of
the paint by the spray guns.
Parts to be painted are dry-sanded or dipped into a bath containing a multi-layer
stripping solvent. This solvent is used until contaminated with paint sludge; it is then
drummed and hauled away as a hazardous (F002) waste. Parts requiring a clean, grease-
free surface for subsequent processing such as inspection or repainting are brought into
the Cleaning Shop. The parts are wiped off and then immersed in a bath of solvent
degreaser. The part is then removed, scrubbed with a brush and rinsed. The USAF uses
a contractor to recycle the contaminated solvent. The solvent is primarily mineral
spirits and is classified as a RCRA D001 waste.
WASTE MINIMIZATION OPPORTUNITIES
Non-Destructive Inspection (NDI)
The primary contaminant (the penetrant) floats on or near the surface because of
its low density. This characteristic makes possible an inexpensive method of periodically
skimming the top layer of fluid in these tanks. By skimming off the top layer and adding
fresh makeup emulsifier or developer, respectively, contaminants floating at or near the
surface can be removed, and suspended contaminants can be diluted.
To eliminate the need for the wet chromate solution, new systems use a dry,
non-hazardous (silica-based) developer. Changing to the silica-based developer would be
technically feasible. The dry developer is technically equivalent and meets the same
specifications as the current wet developer.
Painting/Paint Removal/Parts Cleaning
The plastic media blasting equipment should be used to eliminate the use of
organic solvents in paint stripping. Conversion from wet operation to dry painting booth
operation would result in volume reduction of wastes associated with painting. The Air
Force is implementing the use of high volume, low pressure (HVLP) paint guns. The
amount of overspray solids and VOCs generated can be substantially reduced.
CONCLUSIONS AND RECOMMENDATIONS
The results of the study indicate that the fastest payback (0.24 year) would be
from penetrant skimming option. The capital outlay needed for this option is estimated
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to be only $330. Switching from a wet developer to a dry developer had a payback
period of 27.5 years. This option has moderate capital investment but low cost savings.
If Scott AFB later determines that the wet developer should be treated as a D007 waste,
the disposal costs for wet developer will increase and Option 3 will have higher cost
savings.
Project Summary Title: Waste Minimization Opportunity Assessment: Scott Air Force
Base
Project Summary Availability: Immediate
EPA Project Officer: Jim Bridges/Anne Robertson
Key Words: C-9 medical aircraft; non-destructive wheel inspection; paint stripping; parts
cleaning; printed circuit board manufacture; dye penetrant; paint booths;
polyurethane paint; paint thinner; stripping solvent; paint sludge; Safety-
Kleen 105 degreaser; mineral spirits; silica-based developer; plastic media
blasting; high volume, low pressure (HVLP) paint guns
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FITZSIMMONS ARMY MEDICAL CENTER
OPTICAL FABRICATION LABORATORY
INTRODUCTION
To promote waste minimization activities in accordance with the national policy
objectives established under the 1984 Hazardous and Solid Waste Amendments to the
Resource Conservation and Recovery Act of 1976 (RCRA), the Risk Reduction
Engineering Laboratory (RREL) of the USEPA Office of Research and Development is
supporting WREAFS. The WREAFS Program focuses on waste minimization research
opportunities and technical assessments at Federal sites. The present project focused on
a waste minimization opportunity assessment (WMOA) conducted at the Fitzsimmons
Army Medical Center (FAMC) Optical Fabrication Laboratory (OFL) in Denver,
Colorado.
EXISTING WASTE MANAGEMENT ACTIVITIES
One of the sites chosen for performance of a waste minimization opportunity
assessment (WMOA) under the WREAFS Program is the Fitzsimmons Army Medical
Center Optical Fabrication Laboratory (FAMC/OFL) in Denver, Colorado. Glass lens
fabrication operations at the OFL generate three RCRA hazardous wastes (waste lead-
bearing lens blocking alloy (RCRA D008), alkaline washwater from ground and polished
lens cleaning and deblocking operations (D002), and spent Stoddard solvent from the
tool cleaning operations (D001) and one nonhazardous waste (ground glass fines from
lens grinding and polishing operations). The waste lead-bearing blocking alloy
particulates are reclaimed and recycled at the OFL (to the extent possible); the alkaline
washwater is discharged to the wastewater treatment plant and ultimately used on the
FAMC grounds for irrigation; and spent Stoddard solvent is recycled off-site through a
contractor operation. The nonhazardous ground glass fines are collected from the
present on-site grinding coolant filtration operations and disposed of at a local sanitary
landfill.
Results of the WMOA conducted at the OFL identified three waste minimization
opportunities involving materials in use at the OFL. These options are summarized
below.
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WASTE MINIMIZATION OPPORTUNITIES
Waste Alkaline Washwater
Alkaline washwater from the glass lens cleaning/deblocking operation is currently
discharged from the OFL after passing through a trap to collect large particulates of the
lead-bearing lens blocking alloy. This wastewater is discharged periodically from the glass
lens washing machines at the rate of approximately 200 gal/mo, at a pH of about 13 to
14, and is drained to the FAMC on-site central water treatment facility. Although this
waste is not discharged off-site, it is ultimately discharging lead (both as dissolved lead
and submicron particulates) to the groundwater under the site. It is proposed that this
possibility be avoided in one of two ways:
(1) Use of a source reduction technique-the substitution of a non-lead-bearing
blocking alloy.
(2) Use of a recycling technique—introducing a cartridge filter in the line
leaving the trap from the lens washing/deblocking operation in order to
catch the submicron-size alloy particulates. This technique could recover
up to 500 Ib/yr of particulate material that would ultimately be recycled to
the lens blocking operation.
Glass Fines from the Glass Lens Grinding Operation
The OFL presently generates about 37.5 ton/yr of a mixture of waste glass fines
and water from the lens grinding operation. This material is not a hazardous waste
under the RCRA definition. The OFL currently sends this waste to a local landfill,
thereby incurring both the transportation and landfilling costs. These fines, when dry,
could generate particulate emissions, thus creating possible inhalation problems, during
transportation if they are transported in uncovered or improperly covered containers or
at a landfill if they are improperly covered or managed. A potential use for this material
is as feedstock in glass or ceramic tile production by a local facility. It is assumed that
this facility would use the OFL waste material, and, consequently, the land disposal cost
could be eliminated.
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CONCLUSIONS AND RECOMMENDATIONS
Of the three waste-related opportunities developed at the OFL by the WMOA,
two represent waste reduction for RCRA hazardous wastes, while the remaining option
represents an opportunity to reduce or eliminate nonhazardous waste. None of these
options represent substantial capital outlays or appreciable operating cost savings. In
fact, one waste minimization option—substituting a nonhazardous lens blocking alloy for
the present hazardous material-represents a substantial operating cost increase. The
only positive value of the option is the potential elimination of an environmental
pollution problem if it can be shown at FAMC that a source of lead pollution in
groundwater needs to be eliminated.
Project Summary Title: Waste Minimization Opportunity Assessment: Optical
Fabrication Laboratory, Fitzsimmons Army Medical Center,
Denver, Colorado
Project Summary Availability: Immediate (EPA/600/2-91/031)
EPA Project Officer: Kenneth R. Stone
Key Words: optical fabrication; glass lens; lead-bearing lens blocking alloy; alkaline
washwater; lens cleaning; deblocking; spent Stoddard solvent; ground glass
fines; source reduction; recycling
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FORT RILEY, KANSAS
INTRODUCTION
To promote waste minimization activities in accordance with the national policy
objectives established under the 1984 Hazardous and Solid Waste Amendments to the
Resource Conservation and Recovery Act of 1976 (RCRA), the WREAFS Program
focuses on waste minimization research opportunities and technical assessments at
federal sites. The present project focused on a waste reduction assessment at the U.S.
Army Forces Command (FORSCOM) maintenance facilities at Fort Riley, Kansas.
Results of the Fort Riley, Kansas waste minimization assessment identified two
waste reduction opportunities in a multi-purpose building (Building 8100) used for
automotive subassembly rebuilding, lead acid battery repair as well as a number of other
Army maintenance operations. The two waste reduction opportunities are summarized
below.
EXISTING WASTE MANAGEMENT ACTIVITIES
Waste Battery Acid
Battery acid (32-37 percent sulfuric acid) containing trace concentrations of lead
and cadmium is currently drained from both dead batteries and batteries requiring
repairs, e.g., replacement of battery terminals, and shipped in 15-gallon drums to the
Defense Reutilization and Marketing Office (DRMO) storage facility at the installation
for ultimate disposal as a hazardous waste. Instead, it is proposed that the waste acid be
gathered in a holding tank, particulates removed, and the waste acid adjusted in
concentration to 37 percent sulfuric acid (using 60 Baume commercial sulfuric acid) as
needed for reuse in reconditioned or new batteries. The buildup of dissolved metal
impurities in this recycling system is prevented by purging part of the acid from the
system, it is assumed in this assessment that 25 percent of the acid is purged and 75
percent is reused. The acid being purged is neutralized and treated for trace heavy
metal removal to allow on-site disposal as nonhazardous waste.
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Automotive Parts Washer Wastewater
Dirty aqueous alkaline detergent solution from automotive parts cleaning, which
contains trace concentrations of lead, chromium and cadmium at a pH >12 as well as
the oil, grease and dirt removed from the automotive parts, is currently drained to an on-
site nonhazardous waste evaporation pond. This waste, heretofore regarded as
nonhazardous, is currently being reclassified as a RCRA hazardous waste due to its
characteristics (D007, D008) and will have to be disposed of as a hazardous waste
through DRMO. The proposed waste minimization option for this waste stream would
involve the use of equipment external to the automotive parts washer. The proposed
process would include emulsion breaking to cause emulsified oils to float, removal of
demulsified oils and other tramp oils and grease by skimming, filtration to remove
particulates in an in-line cartridge filter, and addition of fresh alkaline detergent as
necessary, followed by recirculation of the cleaned washwater to the automotive parts
cleaner. Buildup of impurities in the recycled washwater is prevented by purging 25
percent of the used alkaline detergent and recycling 75 percent. The material being
purged is neutralized with an appropriate amount of waste battery acid and precipitated
trace heavy metal impurities are removed to allow disposal of the purge stream as a
nonhazardous waste
Some in-plant experimentation will be needed to determine what type of filter
elements are best suited to this operation, whether multiple cartridge filters are needed,
for how many cycles the recovered wastewater is effective in cleaning automotive parts,
etc. The uncertainty in the proposed procedure is reflected in a 25% contingency in the
capital cost estimate.
WASTE MINIMIZATION OPPORTUNITIES
The battery repair shop generates 7,200 gal/yr of RCRA hazardous waste
(classifications-D002, D006, D008) at a disposal cost of $27,900/yr. Current raw material
cost is $11,530. Recycling of the reformulated battery acid would require a capital
investment of $15,200 but would save $36,000/yr in operating costs. This would yield a
payback of 0.42 years.
Automotive parts washing generates 29,000 gal/yr of RCRA hazardous waste
(classifications-D007, D008). This waste is currently drained to an on-site evaporation
pond. If it were disposed of as a RCRA hazardous waste via DRMO at the same cost
per gallon as the waste battery acid, the disposal cost would be $112,000/yr. Current raw
material cost is less than $100/yr. Recycling of purified alkaline detergent solution would
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require a capital investment of $19,800. This option would save $107,100/yr in operating
costs, leading to a payback period of 0.18 years.
CONCLUSIONS AND RECOMMENDATIONS
In light of the short payback periods of the two waste reduction options identified,
implementation of these options should be considered. Successful application of these
options at Fort Riley creates the potential for application of similar waste minimization
options in at least ten other U.S. Army FORSCOM installations.
Project Summary Title: Waste Minimization Opportunity Assessment: Fort Riley,
Kansas
Project Summary Availability: Immediate (EPA/600/S2-90/031)
EPA Project Officer: James S. Bridges
Key Words: maintenance facilities; automotive subassembly rebuilding; lead acid battery
repair; sulfuric acid; recycling; automotive parts cleaning; recycled
washwater
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HOSPITAL POLLUTION PREVENTION CASE STUDY
INTRODUCTION
In this study, EPA's Risk Reduction Engineering Laboratory (RREL) and the
Department of Veterans Affairs (DVA-Cin) chose to look for pollution prevention
alternatives for minimizing the discarded medical supply wastestream. VA-Cin is
uniquely suited to such a study is directly attributable to its cost sensitivity. The need to
deliver services under a fixed budget has led DVA-Cin to both adopt environmentally
clean practices on its own, and to continue clean practices that cost-reimbursement
hospitals had abandoned.
According to DVA-Cin personnel, approximately 80 percent of the hospital's
supplies are disposed of after a single use. The DVA-Cin saw an additional increase in
the use of disposables in the last 2-3 years due to concern by hospitals over both patient
safety and staff occupational exposure to the AIDS virus. Therefore, the increase results
from greater usage of existing disposable supplies (i.e.,single-use sponges for patient
surgery, and disposable gloves and masks worn to protect hospital staff) rather than from
the use of newly developed disposable items.
EXISTING WASTE MANAGEMENT ACTIVITIES
On average, hospitals generate between 0.5 and 4 pounds of infectious waste per
patient each day. The DVA-Cin facility produces approximately 0.6 pounds of infectious
waste per patient each day, placing it at the low end of the spectrum. However, there
are inconsistencies in how hospitals from different States define what is infectious waste.
For example, DVA-Cin classifies its laboratory waste as general trash after autoclaving.
Inflating the DVA-Cin's quantity of infectious waste to reflect lab wastes would raise the
generation rate to 0.87 pounds per patient each day - still quite low in comparison to
other hospitals. DVA employs waste segregation to minimize infectious waste volume
and also uses cloth gowns instead of disposable gowns.
For this study, a site assessment team was assembled with representatives from
DVA-Cin, EPA, and an EPA contractor to track the flow of disposables throughout the
hospital and review procedures, uses and consumption with department heads. Over a
two-day period, the assessment team visited these DVA-Cin departments: Laboratory
Services; Surgery; Surgical Intensive Care Unit (SICU); 5 South (a patient floor);
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Medical Intensive Care Unit (MICU); Hemodialysis; and the Outpatient Clinic.
A major concern for RREL in conducting this assessment was to look for those
areas in which research and development may support advancing new alternatives. In
learning of the concerns, difficulties and successes of the health care profession, RREL
hopes to expand EPA's experience in the medical waste area and provide a solid basis
for planning future research. Suggestions for further research in the health care industry
are presented below:
RESEARCH AND DEVELOPMENT OPPORTUNITIES
Evaluate Reuse Potential in Single-Use Devices - Using the rigorous investigation
of Hemodialyzers as an example, a cooperative effort could be established between EPA
and representatives of the health care community to undertake the research of other
potential reusable single-use devices and provide substantive data to either support or
reject reuse considerations for these items.
Quality Assurance - Research conducted by the EPA in cooperation with health
care professionals, other Federal agencies (such as the Food and Drug Administration),
and trade associations can form the basis for developing a protocol for reuse, giving
hospitals a standard under which to set down operating procedures and institutional
policies.
Hidden Cost Factors - Confusion exists in comparing the relative costs of
disposables versus reusables. The EPA may wish to conduct analytical studies in
conjunction with health care facilities in order to fully develop and quantify the cost of
using disposable and reusable products, respectively, as an aid in decision making.
Development of Reprocessing Capacity - As health care cost containment gains
increasing importance, reprocessing may become cost effective for some items. The
potential for promoting some reprocessing capability should be explored, particularly in
those areas exhibiting a high density of medical facilities.
Developing a Reusable Market - The EPA and DVA should consider working
together in developing procurement guidelines for the DVA which will stimulate the
production and distribution of reusable and recyclable products.
OBSERVATIONS
DVA-Cin was very pleased with the study and considers the final report a very
usable document for other VA medical facilities. For its part, the EPA hopes to learn
from future cooperation with DVA, seeking the health care professionals advice and
guidance in planning and implementing research programs to respond to the needs of the
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medical community in the areas of hazardous waste, infectious waste, and other waste
streams. Opportunities to reduce these wastes do exist, and additional opportunities will
be uncovered through research. Research will also provide the data on which to make
operational decisions of benefit to health care facilities, while favoring environmental
considerations.
Project Summary Title: Hospital Pollution Prevention Case Study
Project Summary Availability: Immediate (EPA/600/S2-91/024)
EPA Project Officer: Kenneth R. Stone
Key Words: medical supply; disposables; infectious waste; cloth gowns; medical waste;
health care; hemodialyzers; reusable single-use devices; reprocessing;
market; quality assurance
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AIR FORCE PLANT NUMBER 6
INTRODUCTION
The evaluation of emulsion cleaners at Air Force Plant 6 project is part of the
Waste Reduction Evaluation at Federal Sites (WREAFS) Program conducted within the
Pollution Prevention Research Branch. The WREAFS program consists of a series of
demonstration and evaluation projects for waste reduction conducted cooperatively by
the U.S. Environmental Protection Agency (EPA) and various divisions of other federal
agencies. The purpose of this project is to provide assistance to Air Force Plant 6
personnel by documenting the relevant work by other aircraft fabrication facilities to
support comparison of cleaner qualification performance with trichloroethylene for the
vapor degreaser operations at Air Force Plant 6.
PLANT BACKGROUND
Air Force Plant No. 6, located in Marietta, Georgia, is operated for the Air Force
by Lockheed Aeronautical Systems Company. The facility is part of the Aeronautical
Systems Division (ASD), whose headquarters is located at Wright-Patterson Air Force
Base near Dayton, Ohio. There are sk vapor degreaser units that utilize
trichloroethylene (TCE) to prepare steel and aluminum parts for a variety of subsequent
manufacturing steps in the production of C-130 aircraft. The eventual goal of the facility
is to substitute water-soluble emulsion cleaners to obviate use of 650,000 pounds of TCE.
The final report has been compiled for this project. The report contains
information on the evaluation of various substitute cleaners on the conformance of the
emulsion cleaners to be implemented at Air Force Plant No. 6 with specific qualification
test criteria. The document contains the specifications for qualification tests in 17 areas.
It also contains a list of ten cleaners that were targeted for evaluation. The information
for this report was developed by documenting research performed by Boeing Aircraft,
Air Force Engineering Service Center (AFESC), General Dynamics, Lockheed Missile
and Space Company (LMSC), Martin Marietta and Northrop. The report contains a
table summarizing the status of cleaner substitute evaluations conducted by the
represented companies. The document concludes with a chart that compares the
performance criteria of the various companies to the criteria required by Lockheed.
Also, data and information for the report was accumulated from emulsion cleaner
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manufacturers/suppliers and an international workshop on solvent substitution.
EPILOGUE
EPA is working in cooperation with Lockheed Aeronautical Systems Company-
Georgia and Air Force Aeronautical Systems Division to investigate the potential for
implementing emulsion cleaners as a replacement for trichloroethylene (TCE). The
substitution of emulsion cleaners for TCE is currently being implemented at Air Force
Plant No. 6 and EPA will be cooperating with Lockheed and Air Force personnel to
document the successes, problems and costs associated with the change. The results can
then be transferred to similar facilities in the Department of Defense or the Department
of Energy, and can serve to expedite the use of emulsion cleaners at other facilities.
Report Title: Evaluations of Cleaners for Solvent Substitution at Air Force Plant 6
Report Availability: Immediate
EPA Project Officer: Johnny Springer
Key Words: emulsion cleaners; aircraft fabrication; cleaner qualification performance;
trichloroethylene; vapor degreaser; steel; aluminum parts; substitution
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WASTE MINIMIZATION ASSESSMENTS PROGRAM
(ARROW)
This project is designed to evaluate the use of waste minimization assessments in
thirty hazardous waste generating facilities (across ten industries) in New Jersey. The
assessments are being initiated by the New Jersey Institute of Technology (NJIT)
personnel and will follow the EPA recommended procedure outlined in the Waste
Minimization Opportunity Assessment Manual (EPA/625/7-88/003). The New Jersey
Department of Environmental Protection (NJDEP) refers to the project as "Assessment
of Recycling and Recovery Opportunities for Hazardous Waste (ARROW)".
Initial industries being studied include:
0 Electrical Power Generation
0 Graphics Control Manufacturing
0 Paints and Coatings Manufacturing
0 Printing
0 Lubricant Production
0 Transportation Vehicle Maintenance
0 Leather Finishing
0 Educational Facilities
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NUCLEAR POWERED ELECTRICAL GENERATING STATION
INTRODUCTION
The Hazardous Substance Management Research Center at New Jersey Institute
of Technology in association with the New Jersey Department of Environmental
Protection and the EPA's Risk Reduction Engineering Laboratory has undertaken a
demonstration program to evaluate the effectiveness of the EPA Waste Minimization
Opportunity Assessment Manual (EPA/625/7-88/003. July 1988).
The assessment process was coordinated by a team of technical staff from New
Jersey Institute of Technology with experience in process operations, basic chemical
experience, and knowledge of environmental concerns and needs. Because the Manual is
designed primarily to be applied by the staff of the facility, the degree of involvement of
the NJIT team varied according to the ease with which the staff could apply the Manual.
PLANT BACKGROUND
The facility is an electrical power generating plant. The energy is produced by a
nuclear generator. The product of the facility is energy. Hazardous wastes are generated
predominantly during the times when power generation is not in operation. (Radioactive
wastes are not included in this study.) Moreover, it is apparent from the results of the
assessment that the bulk of the hazardous waste from the facility is produced from
construction and maintenance activities largely when the energy generation activity is
shutdown.
EXISTING WASTE MANAGEMENT ACTIVITIES
The facility has implemented several effective steps to reduce waste generation at
the facility. One successful idea involved making surplus materials available to
employees for their personal use. Also, the facility increased its investigation into
opportunities for selling surplus materials to commercial users. Ordering and warehouse
procedures were improved to reduce overstocking and surplus materials. Innovative
material handling procedures such as purchasing materials in large containers and
dispensing them in"just the right amount" containers were developed.
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WASTE MINIMIZATION OPPORTUNITIES
This facility produces electrical energy by a process which depends upon heating
water by a nuclear source. The operation of the facility results in the formation of
radioactive waste which is managed according to the appropriate federal regulations.
The high costs of waste management for this type of waste has encouraged significant
waste reduction efforts in this area throughout the industry. The focus of this
assessment—non-radioactive waste—has similarly benefited from waste reduction efforts,
although the assessment has identified additional options which could be implemented.
Three departmental operations have been found to be associated with the generation of
waste: Maintenance, Site Services, and Operations. In addition, a significant source of
waste for disposal is off-specification and partially used materials which are not easily
associated with any specific operation or job process. Major waste streams identified
were:
* Oil and Oil/Water Mixtures
* Coatings (Paints, Epoxy, Enamels)
* Solvents
* Grease
* Laboratory Reagents
Much of the waste oil stream results from a remediation project at the site and
not directly from the operation of the facility. The other materials result frequently from
regular equipment and facility repair and upgrade activities. Significant quantities of
off-specification and partially used containers of materials are presented for waste
management or disposal. Options identified for waste reduction included strengthened
inventory controls, encourage "just-in-time" delivery of supplies, direct charge back of
waste treatment expenses to the unit or project responsible for the waste, encourage the
use of materials with reduced hazard level, and change frequency or material used for
coating of surfaces.
ADDITIONAL OPTIONS IDENTIFIED
In addition to the options previously discussed other options were suggested. It
was observed that occasionally containers of hazardous waste are found on the site away
from the active secured sections which cannot be identified according to source. It is
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presumed that these materials are discarded by contractors or other non-employees. It is
suggested therefore, that vehicles entering the facility be examined to assure that they do
not leave such containers at the site.
A clear correlation was observed between the amount of full containers and
usable materials presented for waste disposal and the scheduled inspections of the
facility. It is postulated that such materials are discarded in order to demonstrate a
neater appearance to the inspection team. Alternate storage arrangements for such
situations should be developed.
Research Brief Title: Waste Reduction Activities and Options at a Nuclear Power
Generating Facility
Research Brief Availability: December 1991
EPA Project Officer: Mary Ann Curran
Key Words: electrical power generating plant; nuclear; construction; maintenance
activities; surplus materials; ordering ;warehouse procedures; material
handling procedures; inventory controls
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MANUFACTURER OF FINISHED LEATHER
INTRODUCTION
The Hazardous Substance Management Research Center at New Jersey Institute
of Technology in association with the New Jersey Department of Environmental
Protection and the EPA's Risk Reduction Engineering Laboratory has undertaken a
demonstration program to evaluate the effectiveness of the EPA Waste Minimization
Opportunity Assessment Manual (EPA/625/7-88/003. July 1988).
In keeping with the objectives of field evaluation of the Waste Minimization
Opportunity Assessment Manual, the participants were encouraged to proceed through
the organizational steps outlined in the manual. The assessment process was coordinated
by a team of technical staff from New Jersey Institute of Technology with experience in
process operations, basic chemical experience, and knowledge of environmental concerns
and needs. Because the Manual is designed primarily to be applied by the staff of the
facility, the degree of involvement of the NJIT team varied according to the ease with
which the staff could apply the Manual. In some cases, the NJIT role was only to provide
advice, in other cases the team conducted essentially the entire evaluation.
PLANT BACKGROUND
The plant produces finished leathers which are sold to manufacturers of leather
goods such as handbags, belts, shoes, and other items. The operation of the plant varies
according to customer demand. Many different colors, textures, and designs must be
incorporated into the product to meet varying customer requirement, forcing the
operation of several special production steps on an irregular basis. The facility formerly
tanned raw hides, but that process has been phased out as a result of changing supply
and market conditions.
EXISTING WASTE MANAGEMENT ACTIVITIES
This facility receives tanned leather from various sources and transforms it into a
product of higher commercial value by applying "various coatings and other surface
modifications to make it more usable and appropriate for finished consumer products.
The raw materials include, in addition to the leather itself, various water- and
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solvent-based coatings as well as some specialized colorants and other surface
modification products. The solvents typically are aromatic and aliphatic hydrocarbons,
esters, and alcohols.
A typical hide in the manufacturing process might receive one of several finishing
steps. Newly received hides are prepared for finishing by washing, retanning if necessary,
and drying. The aqueous wastes from these steps are sent to the POTW with regular
monitoring to assure compliance. Some hides undergo surface modification by
mechanical buffing. The resulting dust (<100 Ibs/yr) is classified as a hazardous waste
and is disposed of off-site. The back coating step applies essentially the final finish to the
back of the leather while the base coating of the smooth side serves as the primer for
additional finishes to be applied. The coatings are applied using an automated spray
system. The facility has shifted largely to water-based coatings for these steps resulting in
a significant decrease in solvent use. Any over-spray is captured by a water-screen or by
filters and disposed of off-site. The next coating steps are accomplished using
solvent-based materials. No satisfactory non-solvent based coatings have yet been
identified for these finishing steps. The applied finishes are thermally dried with venting
of solvent vapors to the atmosphere. Approximately 130 tons/yr of evaporated coating
solvent are produced through oven drying and as a result of spills and leaks. The final
steps in the manufacturing process are ironing, grading, measuring, and shipping -
operations which are not significant waste-generating activities.
The facility has shifted to the use of water-based coatings, where possible,
moreover, the technical staff continues to evaluate new commercial reduced-solvent
products in order to make further reductions. An optical/computer interfaced system has
been used to determine the shape and position of each hide presented for coating which
is used to control the automated spray coating system, resulting in significant reduction of
overspray.
WASTE MINIMIZATION OPPORTUNITIES
Several waste minimization options were enumerated. A 100% reduction in the
disposal of buffing dust could be achieved by selling the material as a filler in a resin-
based composite product. Solvent losses could be reduced by implementing several
options. As satisfactory water-based materials appear on the market, solvent-based
coatings can be replaced by water-based coatings. The automated spray coating
equipment could be reprogrammed to compensate for required angle spraying. This
could reduce waste by 65% when angle spraying is performed. A solvent capture system
could be installed to allow for the capture and reuse of solvent. Depending on the type
of solvent used, a 90% waste reduction could be achieved. Other improved operating
procedures and minor equipment modifications were discussed.
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In addition to the options previously discussed another option was suggested. It
was observed that the wooden pallets and cardboard used for snipping hides to the
facility might have increased value if recycled.
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Finished Leather
Research Brief Availability: March 1992
EPA Project Officer: Mary Ann Curran
Key Words: finished leather; coatings; aliphatic hydrocarbons; esters; alcohols; aqueous
wastes; automated spray system; water-based coatings; optical/computer
interfaced system; solvent capture system
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LOCAL SCHOOL DISTRICT (K TO 12)
INTRODUCTION
The Hazardous Substance Management Research Center at New Jersey Institute
of Technology in association with the New Jersey Department of Environmental
Protection and the EPA's Risk Reduction Engineering Laboratory has undertaken a
demonstration program to evaluate the effectiveness of the EPA Waste Minimization
Opportunity Assessment Manual (EPA/625/7-88/003, July 1988).
In keeping with the objectives of field evaluation of the Waste Minimization
Opportunity Assessment Manual, the participants were encouraged to proceed through
the organizational steps outlined in the manual. The assessment process was coordinated
by a team of technical staff from New Jersey Institute of Technology with experience in
process operations, basic chemical experience, and knowledge of environmental concerns
and needs. Because the Manual is designed primarily to be applied by the staff of the
facility, the degree of involvement of the NJIT team varied according to the ease with
which the staff could apply the Manual.
FACILITY BACKGROUND
The facility is a school district with a range of activities with potential for
generation of waste which include vehicle maintenance and repair, building cleaning and
maintenance, grounds keeping, instructional programs, and specialized programs such as
science laboratories and art classes. The operations in the district are not centrally
located. There is a common administration building. In addition, there is a high school
for about 1,000 students, a middle school for about 500 students, and six elementary
schools.
The assessment focussed on the administration building and the high school.
Located at the administration building is a central warehouse for building and
maintenance supplies including cleaners, floor care products, paints, and similar
materials. Also at the administration building is the vehicle maintenance and repair
facility. There is also a wood shop which has responsibility for building and repairing
furniture and related items for use within the district. At the high school, paper-,
computer-, and video-based instructional activities occur. In addition, hands-on instruction
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in areas with potential for waste generation also occurs in science laboratories, art
classes, and vocational educational areas.
EXISTING WASTE MANAGEMENT ACTIVITIES
The waste minimization opportunities assessment carried out at a local school
district identified empty paint cans, broken or spilled containers of hazardous materials,
solvent wastes from motor parts degreasing, used oil, motor engine antifreeze solution,
white paper, cardboard, aluminum cans, glass containers, waste chemicals from teaching
laboratories, and vapors from art projects as primary sources of waste.
The district has already instituted several practices which have a positive impact
on pollution prevention. As a result of the"Community and Worker Right-to- Know"
initiatives, the following procedures were emphasized: ordering only the quantity of
materials that can be used in a single year; stocking the materials near the point of use;
conversion to the use of dry copiers replacing the former solvent-based systems. In
addition, there has been a concerted effort to change to water-based paints and cleaners
from solvent-based products where possible and to identify and use other products with
reduced potential toxicity factors in all areas. Moreover, in keeping with municipal
initiatives encouraging recycling - cardboard, white paper, aluminum cans, glass
containers, and used motor oil are collected and recycled. In the industrial arts metal
shop at the high school, cutting oil is recovered by allowing the metal fragments to settle
and then filtering the decanted oil. No new oil for this purpose has been purchased since
1966. Wastes such as laboratory wastes are treated as hazardous wastes and collected by
a contractor for off-site treatment.
WASTE MINIMIZATION OPPORTUNITIES
Several waste minimization options were described. The elimination of hundreds
of empty paint cans could be realized by the purchase of paint in returnable containers.
A 100% reduction in degreasing solvent wastes could be achieved by enlisting the
services of a solvent supply and recycling contractor or acquiring a distillation apparatus.
Utilization of antifreeze recycling technology would eliminate 300 gal of waste antifreeze
solution annually. Laboratory wastes could be minimized by using smaller amounts of
hazardous chemicals and improved inventory control. Hazardous art project wastes could
be minimized by increased substitution of non-hazardous materials for various projects.
ADDITIONAL OPTIONS IDENTIFIED
Other options were identified which could be considered by the district but may
be more pertinent when commercial technology improves. The district uses
chlorofluorocarbons in refrigeration equipment and to a limited extent in motor vehicle
air conditioning. There is already a commitment to change to substitutes with reduced
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impact upon the upper atmosphere. In addition, as mobile air conditioning becomes
more common in district vehicles, a refrigerant recovery and reuse capability should be
considered. In some areas such equipment may become a legal requirement.
Consideration could be given to joint acquisition with the municipal government of
recycling equipment such as antifreeze recycling or degreasing solvent distillation
equipment. Ideally, the equipment should be easily movable to allow it to be taken to the
facility where the need exits.
Research Brief Title: Waste Reduction Activities and Options at a Local Board of
Education in New Jersey
Research Brief Availability: December 1991
EPA Project Officer: Mary Ann Curran
Key Words: municipal recycling; substitution; refrigerant recovery; solvent distillation;
antifreeze recycling; cutting oil; paint waste; high school; administration
building
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A STATE DEPARTMENT OF TRANSPORTATION MAINTENANCE FACILITY
THE TRANSPORTATION MAINTENANCE FACILITY
The major activity at the facility is the maintenance of vehicles used by the
Department, including automobiles and trucks, and to a more limited extent, large
machinery used by the Department such as mowers. Other activities which are carried
out at the facility include wood shop, metal shop, and collection and reuse or disposal of
no longer useful materials. A waste reduction opportunity assessment was carried out in
order to identify specific operations which generate waste at the facility and to propose a
list of options for operational changes which have potential to reduce the waste which is
generated and requires treatment or disposal. Because of the diversity of the activities at
the facility, each individual operating area was examined for the purpose of identifying
waste reduction opportunities.
WASTE REDUCTION OPPORTUNITIES
Oil; From the twelve maintenance facilities in the DOT system, approximately 14,000
gal of used oil are produced each year. This facility generated 2700 gal of used oil
during fiscal year 1989. The facility practices recycling as the preferred management
technique for waste oil. The oil handling procedure at present is to collect used oil in
small drums near work stations and to periodically transfer the contents to a larger
storage tank. Once the storage tank is full, a contracted recycler removes the material
from the site where it is prepared for other beneficial uses.
There are three concerns that generate waste in the oil recycling operation. One
is the sporadic appearance of oil/water mixtures in the storage tank. The second concern
is the relationship between the generator and the contractor who collects the waste oil.
The third area of concern is oil spills. The problems of occasional oil/water
contamination and oil spills can be addressed by implementing improved housekeeping
and materials handling procedures. The problem of timely removal of the waste oil by
the contractor is being addressed by reexamining the purchasing process in terms of
bidding and contracting to make the process more responsive to the time needs of the
capacity of the oil storage tank. A future option may be to investigate methods for
reducing oil usage.
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Antifreeze; Approximately 2000 gal/yr of commercial antifreeze is used at this
maintenance facility. The volume of the waste stream is larger because the coolant in
the engine is a water solution, often about a 1:1 mixture. Current practice is to drain the
cooling system of the vehicles periodically and replace the antifreeze solution with fresh
liquid, discarding the old.
One waste minimization option for antifreeze use is to acquire the use of a
commercial system which will prepare the antifreeze solution for reuse by filtration, pH
adjustment, and additive addition, if necessary. The recycling of antifreeze would cause a
decrease in new antifreeze purchases and in disposal costs.
Freon/CFCs: Freon and other chlorofluorocarbons are present at the facility because of
their use in vehicle air conditioning systems. Based upon purchase data, the use of CFCs
at the facility is about 140 Ibs/yr. There are two substantial pathways for the loss of the
material to the atmosphere. The first is loss through leaks which develop in the air
conditioning systems in the vehicles. The second pathway results from the industry-wide
repair procedure of recharging the system with fresh CFC, locating the leak, discharging
the CFC to the atmosphere, etc.
Two waste minimization options would address the CFC problem. Development
of a regularly scheduled preventative maintenance inspection of all vehicle air
conditioning systems would create loss prevention through leak prevention by avoiding
major leaks. Second, during the repair stage, use of a commercial CFC capture and
reuse device would be advantageous. Such devices are capable of connection to the
vehicle system for recovery of the CFC and have the ability to purify the material to
quality standards which qualify it for reuse.
Paint; The largest quantity of wastes come from the painting operations themselves.
Constructive steps have been taken towards pollution prevention by shifting from solvent-
based paints to water-based paints when possible. Painting operations are also
investigating alternative paint application systems.
Tires; There is an active program for recycling used tires. A contractor periodically picks
up the collected tires (from throughout the DOT system) at this facility and takes them
off-site for recycling. A possible waste reduction option may be to increase the useful life
of the tire in service. This could be done by investigating a new modified tire rotation
procedure. This could also be done by educating employees on driving and parking
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techniques which reduce tire wear.
The DOT maintenance facility has taken steps to minimize its drum/container
wastes and serves as a collection point for other forms of scrap material. It is clear that
this facility has a commitment to the concept of pollution prevention and is putting it to
work in their operations.
Research Brief Title: Waste Reduction Activities and Options at a State
Department of Transportation Maintenance Facility
Research Brief Availability: December 1991
EPA Project Officer: Mary Ann Curran
Key Words: oil recycling; housekeeping; materials handling procedures; purchasing
process; antifreeze recycling; freon; chlorofluorocarbons; CFC recycling;
alternative paint application systems; water-based paints; used tire
recycling; tire rotation; transportation maintenance facility
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A PRINTER OF FORMS AND SUPPLIES FOR THE LEGAL PROFESSION
THE LEGAL SUPPLY COMPANY
The printing company produces, on a quick turnaround basis, legal forms, business
cards, and office supplies for the legal profession. The manufacturing operations of the
facility involve two major procedures. Impressions are made using either an engraving
process or a printing process. These activities and related procedures, including photo
processes and etching, present potential opportunities for waste reduction.
An objective of the company for beginning a waste minimization opportunities
assessment is to identify additional areas within the operation which may be candidates
for waste reduction initiatives, as well as to identify various technical options which may
address these opportunities. One objective of this study was to make the most efficient
use of limited technical time resources by developing a concise listing of opportunity
areas and technology options.
WASTE REDUCTION OPPORTUNITIES
Within the manufacturing process there are two major options-engraving or
printing- which are used for different purposes and products. The first step, a
photographic operation, is common to both.
After the creative design, artistic and layout work are completed by the design
group, a photographic negative is produced using a normal photographic process with
typical development techniques. Subsequently, a phototransfer step is used to reproduce
the image on a metal plate. Copper plates are used in the engraving process and
aluminum plates in the printing process.
Currently, the developer and related solutions are managed as hazardous waste.
Because of the silver content of the photographic process, it is possible that the liquid
waste streams, particularly the spent developer solution, contain enough silver to support
a silver recovery operation.
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The Engraving Process
The primary step within the engraving process where waste reduction
opportunities occur is in the etching operation. Fundamentally, the etching step
accomplishes the chemical removal of unprotected copper from the copper plate creating
depth differences on the plate which can be used to transfer the image to the paper.
The chemical system uses a solution consisting of 55% ferric chloride and 45%
hydrochloric acid. The spent acidic iron and copper chloride solution is currently
disposed of at an annual cost exceeding $10,000.
Three waste reduction options can be proposed for this operation. The first
option is to identify and use an off-site vendor which would regenerate the bath solution
by copper removal, and return the renewed solution to the company for reuse. The
second option would encourage the acquisition of electrolytic equipment to carry out the
bath regeneration on site. The third option is to shift to a new chemical system using a
cupric chloride solution as the etchant rather than the ferric chloride solution now used.
The final step in engraving plate preparation is plate cleaning. Removal of the
polymeric photoresist protective coating is accomplished by immersing the plate in a bath
of N-methylpyrolidone. Currently, the spent solvent from this cleaning process is handled
as a hazardous waste. Two options provide opportunities for waste reduction. One is
recovery and reuse of the organic solvent via distillation. The other option is to switch
from a chemical cleaning process to a mechanical cleaning technique such as polishing,
brushing or sandblasting.
The final operation in the engraving process is the impression itself. Ink sludge is
generated by the cleaning of equipment at the rate of approximately 110 gal/yr. Two
waste reduction options exist for this waste: dewatering via filtration, centrifugation or
drying; or use of the ink solids as raw material in the manufacturing of the ink.
The Printing Process
Two fundamental differences between the engraving process and the printing
process are the type of plate used and the composition of the ink used. The two areas
within the printing process which present the most promising pollution prevention
opportunities are in the impression step and in the equipment cleaning step. The
impression step would involve a change from solvent based inks to a water based ink
system. The equipment cleaning waste reduction option would involve a switch to water
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based cleaner.
Research Brief Title: Waste Reduction Options at a Printer of Forms and Supplies
for the Legal Profession
Research Brief Availability: December 1991
EPA Project Officer: Mary Ann Curran
Key Words: forms; legal profession; engraving; printing; photo processes; etching;
developer; silver; copper; electrolytic equipment; bath regeneration; cupric
chloride solution; recovery; distillation; organic solvent; mechanical
cleaning; dewatering; filtration; centrifugation; drying; solvent based inks;
water based ink; water based cleaner
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UNIVERSITY-BASED ASSESSMENTS PROGRAM
Philadelphia. Pennsylvania
The University-Based Assessments Program is a pilot project between EPA and
the University City Science Center (UCSC) to assist small and medium-size
manufacturers who want to minimize their formation of hazardous waste but who lack
the in-house expertise to do so. Under agreement with the Risk Reduction Engineering
Laboratory of the U.S. Environmental Protection Agency, UCSC's Industrial Technology
and Energy Management (ITEM) division has established three waste minimization
assessment centers (WMACs) at Colorado State University in Fort Collins, the University
of Louisville (Kentucky), and the University of Tennessee in Knoxville. Each WMAC is
staffed by engineering faculty and students who have considerable direct experience with
process operations in manufacturing plants and who also have knowledge and skills
needed to minimize hazardous waste generation.
The WMACs conduct waste minimization assessments for small and medium-size
manufacturers at no out-of-pocket cost to the client. Each client must meet the following
criteria:
* Standard Industrial Classification Code 20-39
* Gross annual sales of not more than $50 million
* No more than 500 employees
* Lack of in-house expertise in waste minimization
The potential benefits of the pilot project include minimization of the amount of
waste generated by manufacturers, reduced waste treatment and disposal costs for
participating plants, valuable education experience for graduate and undergraduate
students who participate in the program, and a cleaner environment without more
regulations and higher costs for manufacturers.
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METHODOLOGY OF ASSESSMENTS
The waste minimization assessments require several site visits to each client
served. In general, the WMACs follow the procedures outlined in the EPA Waste
Minimization Opportunity Assessment Manual (EPA/625/7-88/003, July 1988). The
WMAC staff locate the sources of hazardous waste in each plant and identify the current
disposal or treatment methods and their associated costs. They then identify and analyze
a variety of ways to reduce or eliminate the waste. Specific measures to achieve that
goal are recommended and the essential supporting technological and economic
information is developed. Finally, a confidential report which details the WMACs
findings and recommendations including cost savings, implementation costs, and payback
times is prepared for each client. UCSC conducts follow-up interviews with the client to
determine actual costs and benefits of the recommendations. Research Briefs are
prepared and distributed by EPA to transfer the technical information to others. These
Research Briefs are available from EPA's Center for Environmental Research
Information. The full reports on this research are available from the University City
Science Center, Philadelphia, PA 19104. At the completion of this pilot effort with
UCSC, one hundred facilities will have waste minimization opportunity assessments with
documented results of findings and recommendations.
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MANUFACTURER OF PRINTED CIRCUIT BOARDS
INTRODUCTION
A plant that annually manufactures 4.3 million ft2 of printed circuit boards was
evaluated as part of EPA's University-Based Assessments Program. Both the screens
used to transfer ink patterns to the circuit boards, and the circuit boards are
manufactured at this facility.
WASTE GENERATION & MANAGEMENT ACTIVITIES
Producing Silk Screens
The necessary raw materials include photographic film sheets, Kodak developer,
glue, methyl ethyl ketone (MEK), polyester mesh fabric, KIWOCOL3 screen emulsion,
and tape. After a laser printer produces the pattern on film sheets, the film is developed
with Kodak solution and rinsed. The mesh fabric is stretched and glued onto metal
frames, and an emulsion is spread onto this screen. The film is taped to the screen and
exposed to ultraviolet (UV) light to transfer the pattern to the emulsion coating. A water
rinse removes exposed emulsion and leaves the inverse of the circuit pattern on the
screen. The frames are heat cured.
Producing Circuit Boards
The necessary raw materials include pre-sized zinc/copper-coated fiber glass
panels and screen printing inks. Initial reference holes (6 to 10) are punched on the
panels that are then scrubbed in a mechanical wet scrubbing operation to remove
protective zinc layer from the copper coating. Rinse water is filtered before being
pumped to the plant's wastewater treatment system. Wastewater (23 mil gal/yr) from all
the various processes undergoes treatment ($56,750); sludge (38,000 Ib/yr) is landfilled
($14,160). Paper filters (2,700 Ib/yr) containing copper, zinc, and brush particles are
landfilled ($1,730).
After the panels are printed with etch-resist ink and inspected, they are etched.
This etching process removes unnecessary copper coating and leaves the circuit pattern
on the panel. Necessary raw materials include hydrochloric acid, chlorine gas, caustic
soda, and Sur-Clean micro-etch solution. Panels are first conveyed through etch tanks of
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hydrochloric acid, dissolved gaseous chlorine, and recirculated rinse water. A four-stage
cascade rinse and a stripping etch resist bath follow. Finally panels are micro-etched in a
solution of Sur-Clean 92 to remove oxides, rinsed in a two-stage counter current rinse,
and dried. When the solution is saturated with copper (192,000 gal/yr) , it is bled to a
storage tank and recycled ($110,530). Etch tank fumes are diverted to a continuously
operating fume scrubber. Water from this bath containing caustic soda beads is filtered
to remove etch resist ink particles. Sludge (120 gal/yr) and paper filters (17,860 ft2/yr)
are landfilled ($1,730 and $1,900, respectively). Fumes go to the scrubber. Spent
Sur-Clean solution goes to the plant's water treatment system, and fumes go to the fume
scrubber.
Panels are then screen printed with a solder mask ink, which is UV cured at
300°F; screen printed in white to identify board type; and screen printed in black on the
underside to identify circuit components and again UV cured at 300°F. Waste ink from
all four screen-printing operations is scraped from machines and reused. Screen and
machine-cleaning rags (48,000/yr) containing ink and xylene/propylene solvent are
recycled off-site ($21,890). Broken screen mesh (23,880 ft2/yr) containing emulsion is
landfilled ($1,730).
Ten percent of the panels are solder coated—those that will not have
surface-mounted components. Using this outmoded process relieves production on the
SealBrite coating line. Micro-etching removes oxides. A two-stage counter current rinse
and a hot-air drying follow. In a flux tank, Organo Flux is roll coated onto the panels,
after which the panels are preheated and roll coated with tin/lead solder at 510°F.
Following a three-stage spray rinse, the panels are punched and cut into boards.
In the first stage of the punching operation, 1,500 to 2,000 holes are punched into
panels (either following the solder coating or before the SealBrite coating) for
component wiring. In the second, compound punching stage, the final wiring holes are
punched and the panels are cut into boards. Panel webbing and slugs (643,500 ft2/yr) are
landfilled ($35,600).
Ninety percent of the products are SealBrite coated. This coating, whose function
is similar to that of the solder coat, acts as a base for component attachment and is
applied to punch boards. The necessary raw materials include sulfuric acid, hydrogen
peroxide, SealBrite, SealBrite thinner, and isopropyl alcohol (used to clean the SealBrite
tank). After the boards are micro-etched to remove oxides, they receive a high-pressure
spray rinse, a four-stage cascade rinse, and a roll coating of SealBrite. The tank is
cleaned twice a year and the bottoms drained to the plants waste treatment system.
Water goes to the waste treatment system. Water is reused in the high-pressure spray
rinse. Spent SealBrite solution (165 gal/yr) disposed off-site as a hazardous waste
($7,330); SealBrite thinner (275 gal/yr) evaporates. The boards are then inspected.
About 5% (247,500 ft2/yr) of the panel area is rejected and landfilled ($2,080).
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CURRENT WASTE MINIMIZATION PRACTICES
Presently, the plant possesses a computer-controlled regeneration system which
maintains cupric chloride etch solution. Excess ink is manually scraped from the screens
and returned to the reservoir, and filter presses reduce the volume of wastewater sludge.
WASTE MINIMIZATION OPPORTUNITIES
A closed-loop, chilled-water system using recirculated water to cool the UV ovens
and etch tanks could reduce wastewater 60% at an annual savings of $40,000. The
payback period for the $76,640 implementation cost would be 1.9 yrs.
A steam generation system to heat spent etch solution and drive off a portion of
the water would reduce the volume of spent etchant 35% at an annual savings of
$33,510. The payback period for the $28,180 implementation cost would be 0.8 yr.
Substituting reusable polymer membrane filters for the copper- and
zinc-containing paper filters in the mechanical wet scrubbing operation would reduce
filter waste 96% and save $3,100 annually. The payback period for the $7,700
implementation cost would be 2.5 yrs. Additional recommendations, not completely
analyzed, include:
cleaning screens in an enclosed solvent cleaning system
using reusable filters to remove ink from the stripping etch-resist caustic solution
replacing cupric chloride solution with sulfuric acid/hydrogen peroxide etch
solution
investigating the possibility of recovering cupric chloride etch solution on-site
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Printed Circuit Boards
Research Brief Availability: March 1992 (EPA/600/M-91/022)
Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
Key Words: printed circuit boards; screen printing; SealBrite coating; zinc; copper; fume
scrubbing; etching
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MANUFACTURER OF CHEMICALS
INTRODUCTION
A plant that annually produces approximately 300 million Ib of acrylic emulsions,
low molecular weight (LMW) resins, and herbicides and other specialty chemicals was
evaluated as part of EPA's University-Based Assessments Program. These three process
lines are each described; because one LMW dispersant generates significant quantities of
two hazardous wastes, it is described separately (II. Production of LMW Resin
Dispersant).
WASTE GENERATION & MANAGEMENT ACTIVITIES
Production of Acrylic Emulsion and LMW Resin
The raw materials used to produce acrylic emulsions include monomers, additives,
activators, and catalysts. Producing LMW resins involves monomers, additives, activators,
and catalysts. Monomers are pumped from tanker trucks to storage, then to
holding/premixing tanks, and sometimes to additive, activator, or catalyst holding tanks
for mixing. From the premixing tanks, raw materials are mixed in one of three
steam-heated, pressure-regulated reactors where the polymers are formed. The resulting
acrylic emulsion polymers or LMW resin products are pumped to blend tanks where still
other ingredients are added, e.g., formaldehyde as a preservative. At this point, acrylic
emulsion polymers are pumped through tightly woven cloth filters to separate out
unwanted clumps of product. Then the emulsion is pumped to storage tanks or directly
into drums. The LMW resin product is directly pumped to storage tanks or into drums.
These two production processes generate several wastes on an annual basis.
Burnable liquids are generated as a result of bad mixtures or bad reactions. They are
also generated from incorrect temperatures or batch weight of solution. 15,400 Ib of this
material is disposed annually as hazardous waste at a cost of $77,110. Spillage and
cleanup of material generates 15,400 Ib of composited absorbed monomers which is
disposed of as hazardous at a cost of about $77,110. Off-grade methylolacrylamide and
acrylamide is generated in several ways. Sometimes, bad batches of commercial product
are received. The material has a short shelf life and also off-grade material can result
from operator or equipment error. From the combination of these circumstances, 5,100
Ib of this material are disposed of as hazardous waste at a cost of $40,760. In addition,
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the acrylic emulsion process produces used filters and trapped product from the filtering
process. 4,400 Ibs. of this material is landfilled off-site at a price of $33,080. The LMW
resin process produces unsalable LMW resins in the amount of 20,880 Ibs, disposed of as
hazardous waste for $116,200.
Production of LMW Resin Dispersant
Xylene, diisobutylene (DIB), and other monomers and additives are pumped to
the reactors in the LMW production line. After polymers are formed in the reactors, the
product undergoes separation in settling and storage tanks. Where an emulsion-line
interface of DIB and the product is formed, it is removed. This material (25,750 Ib) is
disposed of as a hazardous waste at a cost of $79,860. During this processing, a DIB wet
solvent is also separated from the product. 316,220 Ibs of this material is burned on-site
in a thermal oxidizer at a cost of $24,500.
Production of Herbicide and Specialty Chemicals
Chemicals are mixed in a pressure-and temperature-regulated reactor where a
specified reaction occurs. The product is then pumped to a blend tank where substances
to reduce the viscosity are added. From this blend tank, the products are loaded onto
railcars and shipped. The highly acidic propionic acid generated by reaction is recycled to
reactors for further use; the low-acidic content acid is used in the wastewater treatment
system to neutralize caustic wastewater. 6000 Ibs of propionic acid waste is generated
from spills while loading and unloading material. $13,510 are spent to dispose of this
material as hazardous. Annual cleaning of the reactor and blend tanks results in 1000 Ibs
of herbicide residues which are disposed of as hazardous at a cost of $24,150.
General Plant Wastes
A Tennessee Pollution Abatement System was installed mainly to remove vapors
with irritating odors. A very small amount is organic vapors. Vapors (99.97%) from the
monomer storage area; knock-out, reactor, and feed tanks; backfire preventers; and the
lower explosive-limit monitors enter a natural-gas-fired thermal oxidizer at 1400°F. Stack
gases (394,200 cu ft) pass directly to the outside atmosphere; recovered heat is used to
heat boiler water. An on-site wastewater treatment facility treats wastewater from the
resin line (including the LMW dispersant process), laboratory, air compressor, cooling
water, and herbicide reactor and blend-tank cleanings. The 300,000 Ib of wastewater
sludge is landfilled at an annual cost of $456,800. The 126 million gal of treated
wastewater is sewered at an annual cost of $2,121,700.
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WASTE MINIMIZATION OPPORTUNITIES
To reduce the amount of off-specification products, upgrading the redundant
sensing and control devices on the reactor raw material lines would reduce burnable
liquids 75%, composited absorbed monomers 19%, off-grade
methylolacrylamide/acrylamide 71%, and unsalable products 15%. The annual savings
would be $139,810, and the payback period for the $365,080 implementation cost would
be 2.6 yrs. The installation of a gas-fired dry-off oven in the wastewater treatment
system would reduce the volume of sludge hauled off-site. Annual savings of $92,730
could be realized as a result of a $70,230 investment.
Research Brief Title: Waste Minimization Assessment for a Chemicals
Manufacturer
Research Brief Availability: March 1992
Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
Key Words: acrylic emulsions; low molecular weight resins; herbicides; chemical
production; thermal oxidizer
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DAIRY
INTRODUCTION
A plant that annually produces 23.4 million gal of milk and milk products, fruit
juice drinks, and jugs from high density polyethylene (HOPE) pellets was evaluated as
part of EPA's University-Based Assessments Program. The raw materials associated with
the various processes include raw milk, liquid juice concentrate, other ingredients such as
chocolate powder, and HDPE pellets.
WASTE GENERATION & MANAGEMENT ACTIVITIES
After raw milk is received and pumped through a clarifier to remove undesirable
solids, it is cooled to 36°F in a cooling press and transferred to one of three storage silos.
About 40% of the cooled, stored milk is directed through a centrifuge to separate the
cream from the milk, with the cream and the skim milk being stored separately. The
cream is either transferred to the ice cream mix process or is packaged for sale as cream.
A portion of the skim milk is transferred to the buttermilk process and a portion to the
pasteurization and homogenization for packaging and sale; the remainder is blended with
whole milk from the storage silo to obtain milk with different fat contents. The blended
milks are sent to the pasteurized milk process, the chocolate milk process, or the ice
cream mix process.
Milks with different percentages of fat and whole and skim milk are pasteurized
and homogenized in two high temperature short time (HTST) presses: the first a
regenerator (heat exchanger), and the second a vacuumizer where milk is steam heated
to 172°F. After homogenization at 1,900 psi, the milk flows through the regenerator,
transferring its heat to the incoming milk. Milk is then cooled to 36°F in a chilled water
heat exchanger and to 32°F in a glycol cooling unit and then transferred to a 10,000-gal
storage tank where it is stored at 33°F. From there the milk is bottled in cardboard
cartons and plastic jugs and stored in a cooler. For buttermilk, skim milk is steam heated
to 186°F, chilled, inoculated with culture at 75°F, chilled to 40° to 45°F, packaged, and
stored. For chocolate milk , blend-tank milk is pumped to a mixing tank where chocolate
powder and fructose are added. It is then pasteurized (as described above), stored,
packaged, and stored again.
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For ice cream mix, milk from the blend tank is blended with cream from the
cream storage tank and with milk powder, fructose, stabilizers, and vanilla. The mixture is
transferred to one of three holding tanks, from there to a HTST press (described in the
pasteurization process), and from there to a 33°F storage tank. After being pumped to a
filling machine, it is packaged and transferred to the storage cooler.
For fruit drinks, city water is pumped through a charcoal filter to remove debris
and chlorine. This water is mixed (in a steam-heated mixing tank [168°F]) with
preservative, liquid juice concentrate, and either sucrose or fructose. Following
pasteurization in an HTST press, the juice is transferred to a surge tank, pumped to a
filling machine,packaged in cartons or jugs, and transferred to a storage cooler.
Each of these processes produce waste:
the 65,000-gal of milk solids annually collected from the clarifier in the raw
milk processing line used off-site as fertilizer at a cost of $8,800;
another 65,000 gal of spills and leaks annually collected in drip pans used
off-site to feed hogs at a cost to the plant of $790;
394-,000 gal of uncontained spills and leaks of contaminated and
uncontaminated milk annually collected in the waste pit and sewered;
the 37,299,660 gal of wastewater from cleaning the physical containers and
machinery needed for the processes (tank trucks, clarifier, storage tanks
and silos, mixing tanks, pipelines, pasteurization presses, filling machines);
from cleaning the plant (where the floor is not only washed as spills occur
but all the floors washed once a day); and from the pasteurization
processes (steam condensate) and the cooling processes (cooling water),
with both sewered because of the risk of contamination, all at an annual
cost of $194,190;
the 6,300 gal of fruit juice spills annually sewered.
Producing the plastic jugs does create another waste. After the HOPE pellets are
melted and extruded in molds for blow-molding gallon and half-gallon jugs, the jugs are
trimmed of excess plastic. No disposal costs are presently associated with the 1,300 gal
of dust that are generated.
CURRENT WASTE MINIMIZATION PRACTICES
The company already has:
• milk solids trucked off-site by a local farmer for fertilizer use,
• waste milk in drip pans taken off-site by a local farmer for hog feed, and
• wastewater and milk-contaminated waste streams combined to achieve dilution
before being sewered.
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WASTE MINIMIZATION OPPORTUNITIES
Recommendations for minimizing waste at the dairy centered on instituting a
waste-water minimization plan-one that would include:
an ongoing employee awareness program, e.g., employees learning how to place
and empty drip pans,
minimizing cleanup water use by using high-pressure and automatic shut-off hose
nozzles, and
installing an activated sludge treatment system to treat the pit-collected
wastewater before it is sewered to avoid disposal surcharges because this waste
does not meet disposal standards.
Employing these recommendations would reduce the uncontained milk waste 38%
and the wastewater 90%, for an annual savings of $320,810. The payback period for the
$661,200 implementation cost would be 2.1 yr.
Research Brief Title: Waste Minimization Assessment for A Dairy
Research Brief Availability: March 1992
Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
Key Words: dairy waste; milk (spilt); activated sludge treatment; wastewater; nozzle,
high-pressure; nozzle, automatic shut-off
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MANUFACTURING HEATING, VENTILATING,
AND AIR CONDITIONING UNITS
INTRODUCTION
A plant manufacturing approximately 700,000 commercial and residential heating,
ventilating, and air conditioning units was evaluated as part of EPA's University-Based
Assessments Program. The plant produces fan coil units, electric heat components, air
treatment units, accessory components (such as air volume control units), and air
terminal units.
WASTE GENERATION & MANAGEMENT ACTIVITIES
Although manufacturing the fan coil and air terminal units is a major source of
waste, the paint line generates the greatest amount of waste. All wastes from the
manufacturing processes are considered hazardous and described in annual terms.
Manufacturing fan coil units generates several wastes. As aluminum sheet is
drawn through the fin press to form fins for the heat exchanger component of the fan
coil unit, 37,500 gal of lubricating oil from the fin press evaporates. The fins and coils
are then joined in an expanding machine. The coil and fin assemblies are then brazed in
a spot brazing machine. During brazing, 440 gal of brazing flux is lost in the form of
fumes. Next, the assemblies are washed in a phosphate wash tank. This process yields
660 gal of phosphate sludge from tank sediment which is disposed of at a cost of $3,900.
Next, the assemblies undergo Boehmiting (an etching process). As a result of
Boehmiting, 1,980 gal of lime sludge are generated. The disposal cost for this material is
$13,200. Eventually, assembly of the fin and coil components into fan coil units takes
place. The assembly is performed with adhesives. One Hundred seven bbl of solvent-
based adhesive on paper (overspray) and defectively glued insulation board are disposed
of at a cost of $23,250. Forty-three bbl of water-based adhesive contaminated material
(paper from overspray and insulation board) are disposed of as municipal
(nonhazardous) waste at a cost of $2,365. Adhesive application requires the use of a
carrier. This generates 345 gal of carrier waste lost due to evaporation. 1320 gal of
hydraulic motor oil from the expander in the fan coil unit is also generated as waste at a
management cost of $7,245.
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Production of the air terminal units generates waste as well. Parts of the units are
washed in a phosphate wash tank. This process yields 1,980 gal of phosphate sludge
from tank sediment which is disposed of at a cost of $11,700. Final assembly of the parts
to form the air terminal units results in the generation of 64 bbl of ethylene-vinyl acetate
adhesive waste (paper and insulation board) which are disposed of at a cost of $13,905.
Paint application generates additional waste. The overspray is collected in water and the
water is separated and recycled. The remaining 6,875 gal of paint sludge is disposed of
as hazardous at a cost of $72,375.
CURRENT WASTE MINIMIZATION PRACTICES
The plant had found water-based (nonhazardous) adhesives unsatisfactory because
of long drying time; they may, however, return to them because the amount of waste is
so great. The plant also intends to remove the paint line from the plant.
WASTE MINIMIZATION OPPORTUNITIES
The suggested waste minimization opportunities concern the adhesive overspray,
paint sludge, and lubricating oil from the fin press in the fan coil unit production line.
Three different opportunities were suggested for minimizing the adhesive
overspray, the defectively glued insulation board, and the adhesive carrier vapor
problems:
• Attach insulation to sheet metal parts with screws, not adhesives. Waste would be
reduced 100%, and the savings would be $58,350. The payback period for the
$6,400 implementation cost would be 0.1 year.
• Replace all solvent-based adhesives with water-based adhesives. (An overhead
conveyor would deliver dry, glued parts to the next operation.) The amount of
solid waste would be the same but would be nonhazardous; all vapors would be
gone; and the net savings would be $25,690. The payback period for the $31,740
implementation cost would be 1.2 years.
• Spot glue 10% of the surface area with quick-drying solvent-based glue and 90%
with slow-drying water-based adhesive. The vapor would be reduced 90%; the
solid waste would be nonhazardous; and the annual savings would be $23,120. The
payback period for the $5,100 implementation cost would be 0.2 year.
To minimize paint sludge, the exhaust air flow rate from the paint booth could be
cut back to reduce the waste 25% at an annual savings of $44,910. The payback period
for the $2,100 implementation cost would be 0.1 year. By improving painting techniques
(through retraining), overspray could be reduced 5% and $8,810 could be saved annually.
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The payback period for the $3,500 implementation cost would be 0.4 year.
To minimize the lubricating oil vapor from the fin press, a recirculating air-oil
condensing system could be installed to reclaim the evaporating oil. The waste would be
reduced 50%, and $56,250 would be saved. The payback period for the $7,400
implementation cost would be 0.1 year.
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Heating, Ventilating, and Air Conditioning Units
Research Brief Availability: March 1992 (EPA/600/M-91/019)
Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
Key Words: heating; ventilating; air conditioning manufacturing; paint overspray;
adhesives; phosphate sludge; lime sludge; ethylene-vinyl acetate adhesive;
adhesive carrier vapor
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MANUFACTURING AUTOMOTIVE AIR CONDITIONING CONDENSERS
AND EVAPORATORS
INTRODUCTION
A plant annually producing 400,000 condensers and evaporators for automotive air
conditioners was evaluated as part of EPA's University-Based Assessments Program.
WASTE GENERATION & MANAGEMENT ACTIVITIES
On the condenser production line such materials as aluminum coils, tube stock,
header assemblies, and extrusions; steel coils; and miscellaneous hardware are cut, bent,
pierced, welded, brazed, and painted. These parts and assemblies go through many
degreasing, rinsing, blowing off, and oven-curing sequences. In the course of these
assembly line procedures, the following wastes are generated: cutting oil,
1,1,1-trichloroethane, methyl ethyl ketone (MEK), brazing slurry, and paint solids, liquids,
and ash. No costs are associated with the parts of these wastes that evaporate: cutting oil,
1,1,1-trichloroethane, and MEK. The management costs to dispose of the gallons and
pounds of waste that are generated amount to $53,000; contaminated paint solids and
liquids are the most costly ($42,270).
The evaporator process line is similar to that of the condenser line except that
paint is not applied to the evaporators. The parts do, however, undergo a chromate
treatment process. Although, with these exceptions, the waste disposal costs are similar
($11,300 for the evaporator line and $10,730 for the condenser line), the disposal costs
for the chromate surface treatment exceed $98,000. On both process lines, much
wastewater is carried to a nonchromate wastewater facility where treatment produces 576
cu yd of waste-water sludge whose annual management cost exceeds $158,500.
The plant employs several other waste management measures. It operates an
extensive wastewater treatment plant. The plant also captures some of the slurry runoff
from the spray process in small runoff troughs on the spray brazing booths. Fume
scrubbers on the brazing oven stacks capture slurry particulates from the stack gases.
Toxic hexavalent chromic acid waste is converted to the trivalent form before removing it
from the plant.
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WASTE MINIMIZATION OPPORTUNITIES
The greatest waste management cost on the condenser line concerns disposal of
contaminated paints; the greatest savings proposal also concerns the liquid and solid
paint waste. By replacing the dip paint system with an electrostatic epoxy powder paint
coating system, not only would there be more even coating of the complex surfaces, the
waste could be reduced 100% and the savings, including costs of raw materials, would be
$133,820. The payback period for the $130,320 implementation cost would be 1 yr.
An alternative to this waste paint disposal opportunity could be to modify the dip
paint system. By increasing the time the parts drip into the paint tank and by tilting them
back and forth, 40% of the pounds of paint waste could be reduced at a savings of
almost $20,000. The payback period for the $25,440 implementation cost would be 1.3 yr.
By covering the 1,1,1-trichloroethane troughs on the condenser and evaporator
process lines, the evaporative loss could be reduced 50% and the annual savings would
be $14,000+, including raw materials. The payback period for the $1,880 implementation
cost would be 0.1 yr.
Wastewater sludge could be reduced 75% by installing a dry-off oven to reduce
the volume of hauled-off sludge, and a 1% reduction could be achieved by modifying the
brazing slurry runoff to reuse 40% of the slurry. The first change would annually save
almost $24,000 (over and above oven operating cost); cost $28,440 to implement; and be
paid back in 1.2 yr. The second change could save almost $4,000, cost almost $5,000, and
be paid back in 1.3 yr.
Additional recommendations, not completely analyzed but presented to the plant
management, include:
pumping the 1,1,1-trichloroethane to cleaning troughs rather than transferring it
manually in buckets
using an alternative fluxing system with less hazardous material
analyzing treated water from the nonchromate system to determine if more could
be reused
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Automotive Air Conditioning Condensers and Evaporators
Research Brief Availability: March 1992
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Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
Key Words: automotive; air conditioning condensers; evaporators; cutting oil;
1,1,1-trichloroethane; methyl ethyl ketone (MEK); brazing slurry; paint
solids; dry-off oven; electrostatic epoxy powder paint coating system
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MANUFACTURER OF COMPONENTS FOR AUTOMOBILE AIR CONDITIONERS
INTRODUCTION
This plant manufactures three distinct product components for automobile air
conditioners: charged air coolers, round tube plate fin (RTPF) condensers, and air
conditioner tubes .
WASTE GENERATION ACTIVITIES
Charged Air Coolers
Sand-cast aluminum tanks are cleaned in an aqueous alkaline bath at 160°F, rinsed
in successive stages, air dried, and inspected. Air and turbulator fins, headers, and side
sheets are fabricated; hand-assembled into air coolers; brazed; and painted. The wastes
include:
lubricating oil, when coil stock is made into air fins, turbulator fins, headers, and
side sheets and when extruded aluminum tubes are cut to length and deburred,
scrap metal, when headers and side sheets are made from aluminum coil stock,
spent solvent (trichloroethane, perchlorethylene) from degreasing operations, and
paint booth wastes from solvent and paint from paint gun cleaning,water from the
paint booth's water curtain, waste paint solids, and overspray.
Round Tube Plate Fin Condensers
Steel headers, aluminum hairpins, and aluminum coil stock (for fins) are fashioned
into parts, degreased ( perchlorethylene), dried , assembled into the condenser body,
brazed, flushed with hot water, leak tested, oven dried, and dip painted. Wastes similar to
those for the charged air coolers (above) are generated.
Air Conditioning Tubes
Aluminum coil tubing is cut to length, formed and straightened. About 39% of the
product is degreased (trichloroethane). The other 61% is welded, pierced, and welded
again before being degreased, dried, and leak tested. Cutting oils and solvent wastes
occur.
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WASTE MANAGEMENT ACTIVITIES
This plant generates several different types of waste annually. Approximately 40
barrels of spent oil are disposed of off-site. 25 barrels of still bottoms (one third of
which is trichloroethylene, the remainder - perchlorethylene) are disposed of off-site.
1,384,000 gal of process wastewater are treated and put to the sewer. 255,377 Ibs. of
aluminum and steel scrap are sold for reuse. 20 barrels of paint sludge are disposed of
as hazardous waste.
The plant presently has a solvent distillation unit to recover spent solvent and a
secondary still to recover solvent from the first still's bottom. It has virtually eliminated
sludge from its wastewater treatment system, and also sells scrap aluminum and steel (for
$146,500/yr).
WASTE MINIMIZATION OPPORTUNITIES
By replacing the chlorinated hydrocarbon solvents with degreasers that can be
directly sewered, waste disposal costs would be reduced $6,007/yr and raw material cost
savings would amount to $62,640/yr. The payback period for the $20,700 implementation
costs would be 0.3 yr. Note that of the 11,000+ gal of solvent used each year, 92% to
98% is lost to evaporation.
By not feeding water to idle rinse tanks and by converting these tanks to a
counterflow rinse system, $33,235 would be saved each year. The payback period for the
$3,480 implementation cost would be 0.1 yr. By converting present painting operations
to electrostatic powder coating, solvent and wastes (water, paint solids, used plastic liners,
spray booth coating) would be reduced or eliminated. Each year, waste disposal costs
would be reduced $5,869 and raw material cost savings would amount to $22,885/yr. The
payback period for the $100,640 implementation cost would be 3.5/yr.
By fabricating lightweight plastic tops to cover the degreasing units when not in
use, solvent evaporation would reduce raw material costs at a savings of $26,375/yr. The
payback period for the $3,600 implementation cost would be 0.1 yr.
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Components for Automobile Air Conditioners
Research Brief Availability: March 1992
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Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: F. William Kirsch
EPA Project Officer: Emma Lou George
Key Words: automobile air conditioners; aluminum; steel; degreaser; trichloroethane;
perchlorethylene; distillation; scrap; painting wastes; electrostatic powder
coating
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REFURBISHING RAILCARS, WHEEL SETS, AND AIR BRAKES
INTRODUCTION
A company rebuilding approximately 2,000 railcars a year was evaluated as part of
EPA's University-Based Assessments Program.
WASTE GENERATION & MANAGEMENT ACTIVITIES
Refurbishing a railcar requires several steps which generate waste. The railcars
are mechanically shaken to remove dirt and other residue from the cars. Next the cars
are cleaned with a high pressure water spray. After the removal of any damaged parts,
the paint removal process takes place. The paint removal process employs a steel grit
blast system which slings steel grit against the car's metal surface. The paint chips and
grit are conveyed to an outdoor cyclone. The cyclone separates the reusable steel grit
from the paint dust and spent steel grit. 225 tons of steel grit and 214 tons of paint dust
are shipped off-site for disposal as hazardous waste at a cost of $95,560 annually.
After the old paint is stripped away, primer is applied using hand-held spray guns.
Once the cars are reassembled, the paint application takes place. The paint is applied
using hand-held spray guns also. 56,042 Ibs of overspray from paint and primer
application processes are disposed of as hazardous waste at a cost of $36,860 on a yearly
basis. Additionally, 6000 gal/yr of solvents used as paint thinners are lost due to
evaporation.
To recycle axles from the railcars, the axle is washed in caustic solution to remove
dirt and grease. 2400 Ib/yr of sludge from this process are disposed of as hazardous
waste at a cost of $5,350/yr. The plant also rebuilds air brake components. In the
rebuilding process, external debris are removed from the components with a plastic bead
blast system. As a result, 900 Ib/yr of spent beads and paint residue are disposed of as a
hazardous waste costing $5,200/yr.
The plant had already installed a water treatment facility, discontinued use of
methylene chloride to wash the axles, and contracted with a vendor to reclaim solvent
used to clean the air brakes.
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WASTE MINIMIZATION OPPORTUNITY
Three of the recommended minimization opportunities centered on the painting
operation:
• By installing an electrostatic spray system, primer and paint overspray losses would
be reduced by 15% and solvent losses by 1.4%, at an annual savings of $11,080.
The payback period for the $58,320 implementation cost would be 5.3 years.
• By improving the painters' techniques, use of paint and primer would be reduced
5% and solvent 5%, at an annual savings of $4,820. The payback period for the
$3,500 implementation cost would be 0.7 year.
• By covering the painting areas with plastic sheets to collect paint and primer
residue, the waste would be reduced 5% and $1,540 would be saved annually.
There would be an annual operating cost but no capital implementation cost.
Another recommendation concerned the steel grit operation. Presently, 90% of
the coatings are removed. Plant personnel indicated that removing 75% would not affect
quality. By modifying this operation, 17% of the annual waste could be reduced at a
savings of $24,980, including the cost of raw material. The payback period for the $13,500
implementation cost would be 0.5 year.
Additional recommendations (not included because of insufficient data, or difficult
implementation, or lengthy payback period) that may become attractive include:
custom design a system to separate spent steel grit (nonhazardous) and paint
residue
mechanically preclean the axle to remove some concentrated, relatively dry
residue that otherwise becomes part of the wash system sludge
install an ultrasonic axle wash system to eliminate the caustic wash
eliminate air drafts to reduce paint overspray in the railcar painting sheds.
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Rebuilt Railway Cars and Components
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Research Brief Availability: Immediate (EPA/600/M-91/017)
Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Brian Westfall/Emma Lou George
Key Words: railcar rebuilding; cleaning; railcars; paint; primer; overspray; separation;
oil; electrostatic paint spraying.
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MANUFACTURER OF PERMANENT-MAGNET DC ELECTRIC MOTORS
AND REPLACEMENT PARTS
INTRODUCTION
A plant that annually manufactures approximately 13 million permanent-magnet
DC electric motors and replacement parts was evaluated as part of EPA's University-
Based Assessments Program.
The raw materials used in the various processes include iron and aluminum
castings; steel tubing, shafting, and laminations; copper wire and commutators; poles;
epoxy coating; varnish; adhesive; and cleaning chemicals. Fan components are purchased.
The armature and the stator are made separately and then assembled.
WASTE GENERATION & MANAGEMENT PRACTICES
The armature assembly generates several sources of waste. During cutting and
machining of steel shafts, 17,160 Ib/yr of waste coolant is generated. This material is
disposed of as a hazardous waste at a cost of $5,504/yr. The plant has already installed a
coolant recovery system that recovers almost all coolant for reuse in machining tools.
Scrap metal is also generated. 1-1/2 truck loads of this material are reclaimed annually.
Later, the assembled armatures are dipped into an epoxy powder dip tank. This
process creates 5,175 Ib/yr of waste epoxy dust which is collected in bag filters. This dust
is disposed of as a hazardous waste at a cost of $3,948 annually.
Near the end of the armature assembly, varnish is applied. Occasionally, varnish
becomes too thick for proper application. This results in the generation of 920 Ib/yr of
hazardous waste that is disposed of at a cost of $524/yr.
The stator assembly begins with the machining of steel tubing. Afterwards, the
parts are cleaned in a 5-stage tank washing line to prepare the surface for adhesive
fastening of magnetic poles. This cleaning process annually generates 3,520 Ibs of zinc
phosphate and caustic sludge which is disposed of as a hazardous waste. Wastewater
from the tanks is neutralized and pumped to the sewer.
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After final assembly of the motors, approximately 2% of the plant's products are
painted black for cosmetic purposes. The spray-painting process generates several
wastes. 7,920 Ib/yr of spray paint booth wastes in the form of paint overspray, plastic
sheets and air filters are disposed of as hazardous at a total cost of $6,151/yr. The water
from the water curtain is too contaminated to be reused so it is disposed of as a
hazardous waste (8,840 Ib/yr) at a cost of $3,463/yr. 2,640 Ib/yr of spent solvent from
cleaning paint spray guns is disposed of as a hazardous waste at a cost of $719/yr.
WASTE MINIMIZATION OPPORTUNITIES
The two operations generating the most waste are the painting operations and the
five-stage washer assembly line.
Alternatives to control liquid and solid paint wastes include:
• Replacing the water curtain spray booth with an electrostatic powder
system to reduce solid paint wastes 93% and liquid wastes 100% at an
annual savings of $10,230. The payback period for the $78,440
implementation cost would be 7.7 yr. Or,
• Replacing compressed-air paint spray guns with air-assisted airless paint spray
guns to reduce paint overspray and increase paint adhesion. This would reduce
both the liquid and the solid paint wastes 50%, with an annual savings of $5,850.
The payback period for the $10,000 implementation cost would be 2.6 yr. Or,
• Replacing the water curtain spray paint booth by using a presently inactive
electrostatic spray paint booth to reduce raw material costs and the amount of
waste: 47% of the paint solids and 50% of the paint liquids at a savings of $9,970.
The payback period for the $7,000 implementation cost would be 0.7 yr.
Ninety percent of spent epoxy powder could be recycled by installing an air-tight
collection system at an annual savings of $14,470. The payback period for the $6,480
implementation cost would be 0.5 yr.
For a 100% reduction in the waste generated at the five-tank washer line in the
stator assembly line, the use of the pole adhesive could be discontinued. Instead, the
poles could be mechanically attached to the inside of the stators. The annual savings
would amount to $31,760, and the payback period for the $110,880 implementation cost
would be 3.5 yr.
Several additional recommendations, not completely analyzed, were brought to the
manufacturer's attention for future reference. One recommendation was to install
drag-out boards on the five-step cleaning operation tanks to drain solutions back into the
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tanks. Another recommendation suggested collecting the paint-spray-gun cleaning
solvent for reuse. There is the possibility of using a detergent or a water-based solvent to
clean dirty, metallic raw material. In the future, consideration should be given to
converting the varnish spray system to a robotic dip system. And as an alternative to
discontinuing the adhesive fastening process, an automatic metering system could be
installed to reduce the amount of excess adhesive used to attach poles.
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Permanent-Magnet DC Electric Motors
Research Brief Availability: March 1992
Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
Key Words: permanent-magnet DC electric motor manufacturer; paint wastes; epoxy
powder; electrostatic paint spraying; adhesives
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MANUFACTURER OF METAL BANDS, CLAMPS, RETAINERS, AND TOOLING
INTRODUCTION
A plant that annually produces 2 million Ib of metal clamps, bands, retainers, and
tools was evaluated as part of EPA's University-Based Assessments Program. The raw
materials used for these products include stainless steel, carbon steel, forged iron blanks,
zinc electroplating solution, brightener, and all the necessary cutting, cleaning, and rinsing
chemicals.
WASTE GENERATION ACTIVITIES
To form the bands, 24-in. stainless-steel coils are cut and the sharp edges removed
and beveled. The stainless-steel scrap is sold to a scrap metal dealer. To form the
buckles, stainless and carbon steels are punched and crimped onto one end of the bands.
For cylindrical bands, the open end is inserted into the buckle. For open-ended clamps,
the buckle is only crimped onto one end. After inspection, the bands are packaged and
stored for final shipment.
For customers who purchase the bands and buckles separately, the company
fabricates specialized tools to apply and install the clamps and fittings. It is the
manufacturing of these tools that creates the greatest portion of the plant's waste.
In the tool manufacturing process, many wastes are generated. In the ensuing
discussion, all waste and disposal cost data are presented in terms of annual rates. First,
iron blanks (which are forged off-site) are machined into tools on-site. Waste cutting
fluid and hydraulic oil are generated from this process step at the rate of 660 gal/yr. This
material is incinerated off-site at a cost of $70. After further processing, the tools are
placed in electroplating barrels where they enter a metal cleaning line.
Initially, the tools undergo caustic cleaning. 1,120 gal of spent caustic cleaner
(containing sodium hydroxide and sodium metasilicate) is pH balanced and discharged to
the sewer system as industrial waste water. Next, the tools receive acidic electrocleaning.
560 gal of alkaline electrosoap solution is pH balanced and discharged as industrial waste
water also. 170 gal of sludge from the caustic cleaning tank and the electrosoap tank is
drummed and disposed of as hazardous waste at a cost of $1,200. After acidic
electrocleaning, the tools proceed through the tap water rinse stage. This stage generates
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650,000 gal of wastewater which is sewered at a cost of $750. The next stage of the
cleaning process is the acidic cleaning. 560 gal of spent cleaner containing sodium
fluoride is pH adjusted and sewered. Following this step, 650,000 gal of wastewater is
generated with a disposal cost of $750 during the cascade rinse phase. The final step in
the metal cleaning line is the acid stripping step. During this step, 170 gal of acid
solution is disposed of as hazardous waste at a cost of $900.
Once the metal cleaning phase is completed, the tools pass through an
electroplating line. This line involves acid zinc plating, rinsing and brightening. From the
acid zinc plating line, 280 gal of solution containing sulfuric acid and ammonium chloride
is disposed of as hazardous waste at a cost of $1,200. Wastewaters from the rinsing steps
are recycled and reused; however, 230 gal of sludge is disposed of as hazardous waste
costing $1,000. During the brightening step, 170 gal of hazardous waste in the form of
solution containing nitric acid, chromium nitrate and ammonium bifluoride is disposed of
at a cost of $700.
CURRENT WASTE MINIMIZATION PRACTICES
The plant has already taken the following waste minimizing steps:
segregated excess metal for sale to a scrap dealer,
treated plating-line rinse water (to remove metal contaminates) for reuse,
employed air-agitation for zinc-plating-line rinses,
filtered zinc plating solution to remove solid contaminants,
discontinued using leaded steel, and
employed cascade rinses in the metal cleaning and zinc plating lines.
WASTE MINIMIZATION OPPORTUNITIES
Presently the first rinse in the metal cleaning line uses tap water as make up. By
redirecting the cascade rinse overflow to replace the tap water make up, 650,000 gal less
of water will need to be purchased and sewered. The net annual savings would be
$1,090. The payback period for the $470 implementation cost would be 0.4 yr.
By segregating high-grade from lower grade scrap, no waste reduction would
occur, but the cash received from the recycler would increase.
To generate less sludge in the caustic cleaner tank, use deionized rather than tap
water in the reagent baths on the metal cleaning and electroplating lines. The waste
would be reduced by 150 gal/yr for a net savings of $1,370 after the rental cost of the ion
exchange unit is considered. With no implementation cost, the payback is immediate.
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To reduce water use in the tap-water and cascade rinses, flow reducers and flow
meters could be installed on the metal cleaning line. This reduced use (124,800 gal/yr)
would save $220/yr. The payback period for the $130 implementation cost would be 0.6
y.
Increasing the drainage time over the caustic cleaner and electrosoap tanks would
reduce waste by 250 gal/yr and save $340^r with no required implementation cost.
Several other recommendations made to the company include:
having a formal cutting-fluid management program to reduce the volume needing
disposal,
replacing kerosene with a nonhazardous cleaner,
installing an automated pH adjuster for metal cleaning line effluent to prevent
compliance problems, and
installing splash guards on some machines to reduce loss of cutting fluids and
lessen unnecessary cleanup.
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Metal Bands, Clamps, Retainers, and Tooling
Research Brief Availability: March 1992
Assessment Responsibility: Colorado State University Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
Key Words: metal bands; metal clamps; tool manufacturing; stainless steel; metal
cleaning, caustic cleaners; acid cleaners; cascade rinse, zinc plating;
brightener; sludge
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MANUFACTURER OF ALUMINUM EXTRUSIONS
INTRODUCTION
A plant that annually manufactures over 36 million Ib of aluminum extrusions was
evaluated as part of EPA's University-Based Assessments Program. These extrusions are
made for the use of other product manufacturers.
WASTE GENERATION ACTIVITIES
Virgin aluminum ingots, scrap aluminum, and alloying metals (e.g., copper, zinc,
nickel) are melted in natural-gas-fired furnaces. The molten metal is then cast into logs in
a water-quench hydraulic cast system, heat-treated and extruded into desired shapes;
sheared; heat-treated again; and then buffed, anodized, or painted. Each year
approximately 1.3 million Ibs. are buffed and shipped; 14 million Ibs. are anodized,
colored, and sealed or anodized and sealed then shipped; and 21 million Ibs. are painted
and shipped. These three procedures (buffing, anodizing, and painting) create the wastes
of interest.
CURRENT WASTE MANAGEMENT PRACTICES
The buffing procedure annually generates 26,000 Ibs. of buffing compound sludge
which is disposed in an on-site landfill along with 7,271 used buffing pads. The anodizing
procedure annually is a major contributor to wastewater generation. Wastewater, fume-
scrubber wastewater, and overflow water are sent to caustic or acid waste lagoons or to a
reaction pit for further treatment and disposal. The painting operation generates
wastewater also. Along with wastewater, painting generates 50,000 Ibs. of contaminated
air filters and plastic sheeting which are landfilled off-site as hazardous wastes. The
cleaning of paint lines results in the evaporation of 13,130 gal of toluene annually and
1,430 gal/yr of spent toluene is disposed of off-site as a hazardous waste. Annually,
240,000 Ibs. of trivalent chromic sludge are disposed of in an on-site landfill. 1,800,000
Ib/yr of wastewater sludge are deposited in an on-site landfill also. Approximately
47,160,000 gal of wastewater are treated at this plant on a yearly basis.
Already, the plant is taking steps to change its hazardous wastes. The plant is
currently transforming toxic hexavalent chrome to nontoxic chrome before off-site
shipment. It is also controlling suspended and dissolved species concentrations in
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effluent water in an on-site wastewater treatment facility and using a water-spray fume
scrubber in the anodizing area for air quality control.
WASTE MINIMIZATION OPPORTUNITIES
By replacing the solvent-based painting system with an electrostatic powder
painting system, not only would the powder coating produce a more even coating, the
spent and evaporated toluene, used air filters and plastic sheets, paint ash, and
evaporated solvents would be reduced 100%. The net annual savings, which would
include the lower cost of powder coatings, would be $1,084,440. The payback period for
the $147,580 implementation cost would be 0.1 yr.
By installing an array of rinse spray nozzles in the anodizing line (above the
detergent, etch, acid de-smut, anodizing, stannous sulfate, nickel fluoride seal, Sandoz
bronze and Sandoz seal tanks) to spray water onto each parts rack as it is raised from
the tank; by installing drag-out boards on all tanks in the line; and by increasing the drain
time over the tanks, wastewater sludge would be reduced 0.2% at an annual savings of
$52,900. The payback period for the $28,910 implementation cost would be 0.5 yr.
By installing an automatic metering system to minimize the amount of buffing
compound used, the buffing compound sludge would be reduced 20%, at an annual
savings of $6,590. The payback for the $25,960 implementation cost would be 3.9 yrs.
By installing a distillation unit, 80% of the spent toluene would be
recovered-toluene that could then be used to clean the paint lines. The annual savings
would be $17,030. The payback period for the $37,060 implementation cost would be 2.2
yrs.
By recovering and recycling caustic and acid solutions in the rinse tanks of the
anodizing process line, raw materials lost in the rinsing operations would be recovered
and water purchases reduced. Wastewater sludge would be reduced 0.2% and
wastewater 85%. The annual savings would be $105,480, and the payback period for the
$419,160 implementation cost (for dedicated reverse osmosis solution recovery system, an
electrodialysis unit, in-tank air agitation units, and a lowered flow rate of water through
the rinse tanks) would be 4 yrs.
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Aluminum Extrusions
Research Brief Availability: March 1992
Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
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Key Words: aluminum; aluminum extrusion waste; buffing; buffing compounds;
anodizing; painting; paint wastes; electrostatic powder painting; Sandoz
bronze; toluene; chromium
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MANUFACTURER OF ALUMINUM CANS
INTRODUCTION
A plant producing 1 billion 12-ounce aluminum cans each year was evaluated as
part of EPA's University-Based Assessments Program.
WASTE GENERATION ACTIVITIES
After the cans are formed, they pass through automated spray washing machines
where they are cleaned and rinsed. The can is surface treated so the outside can receive
a base coat of paint, a printed insignia, and a final coat of clear lacquer. The inside
receives a water-sealed vinyl coating. Between these steps the cans are dried.
Most of the hazardous waste comes from the can washing operation. The rinse
water from this operation contains oil, hydrofluoric acid, sulfuric acid, nitric acid, and
ammonium fluozirconate. The water is treated on-site and discharged to the sewer. The
sludge precipitated from the rinse water treatment process is laden with ammonium
fluozirconate and must be hauled off-site for hazardous waste disposal. The printing and
inking operations generate additional wastes. Tap water from rinsing operations
generates 30,699,000 gal/yr. Sludge precipitated from the treated tap water is
accumulated at the rate of 888,300 Ib/yr. Also, painting operations yield 5,400 gal of
paint waste. The total cost to treat and dispose of these three sources of waste is
$249,850.
CURRENT WASTE MINIMIZATION ACTIVITIES
The company already recycles its scrap aluminum, keeps to a minimum its use of
water and chemicals in the washing operation, uses a filter press to reduce the water
content of the hazardous sludge before shipment off-site, and collects waste oil from the
extruder coolant system.
WASTE MINIMIZATION OPPORTUNITY
The suggested waste minimization opportunity concerns the hazardous sludge. By
substituting a nonhazardous reagent for the presently used 2%to 4% ammonium
fluozirconate, the need to dispose of the sludge at a hazardous waste disposal facility
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would be eliminated, and $133,060 would be saved. Because there are no implementation
costs, the payback period is immediate.
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Aluminum Cans
Research Brief Availability: Immediate (EPA/600/M-91/025)
Assessment Responsibility: Colorado State University Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Brian Westfall/Emma Lou George
Key Words: aluminum can manufacturing; sludge; cleanings, aluminum cans; ammonium
fluozirconate
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MANUFACTURER OF TREATED WOOD PRODUCTS
INTRODUCTION
This plant produces treated wood products (crossties, poles, lumber) for regional
distribution, annually processing about 1.7 million cubic feet of wood on a full-time
schedule, 8,760 hours per year. The major process operations are debarking and
trimming, treating lumber with a chromated copper arsenate solution in pressure
cylinders (Wolmanizing), treating crossties and poles with a mix of creosote and No. 6 oil
in pressure cylinders, and steam-cleaning the crossties and poles in the pressure cylinders
to remove excess creosote. All these operations result in the formation of waste streams,
and all except bark and wood chips are considered hazardous waste. This plant was
evaluated as part of EPA's University-Based Assessments Program.
WASTE GENERATION ACTIVITIES
Solid wastes (bark and wood chips) from debarking and trimming are stored on-
site, awaiting disposal, and are accumulating at a rate of 9,750 cubic yards per year at a
waste management cost of $l,200/yr. Spent chromated copper arsenate solution (2%
aqueous, 280 gal/yr) from Wolmanizing operations is shipped to a hazardous waste
disposal facility at a cost of $700.
Steam cleaning of crossties and poles results in a condensate containing creosote
and oil. After addition of a flocculating agent, settling, and decanting, the creosote layer
is recycled to the process. The aqueous layer (720,000 gal/yr), after treatment with ozone
and caustic soda to destroy soluble phenols and adjust the pH, is discharged to the sewer
as industrial waste water at a cost of $4,175. Cleaning of the creosote treatment
cylinders results in a creosote sludge. Some is shipped off-site for use as a boiler fuel,
and the rest (16,550 gal/yr) is sent to a hazardous waste disposal facility at a cost of
$16,625.
CURRENT WASTE MINIMIZATION PRACTICES
The plant has minimized the need for periodic cleaning by fitting the large storage
tanks with conical bottoms to accumulate sludge. These storage tanks are heated to
maintain proper viscosity and reduce sludge formation. Also, because the plant now
employs Wolmanizing (a closed-loop process that does not require steam cleaning), waste
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containing chromated copper arsenate has been minimized.
WASTE MINIMIZATION OPPORTUNITIES
If a waste exchange program could be arranged with a user of scrap wood, the
9,750 cu yd of bark and wood chips could be removed, and the property leased for its
storage would not be needed. This would save $l,200/yr and would cost nothing to
implement.
Research Brief Title: Waste Minimization Assessment for a Plant Producing
Treated Wood Products
Research Brief Availability: March 1992
Assessment Responsibility: Colorado State University Waste Minimization
Assessment Center
UCSC Reviewer: J. Clifford Maginn
EPA Project Officer: Emma Lou George
Key Words: bark; wood chips; lumber treated; Wolmanizing; creosote; No. 6 oil; copper
arsenate
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MANUFACTURER Of MILITARY FURNITURE
INTRODUCTION
A plant that annually builds, to specification, approximately 12,000 units of
furniture for use in military barracks was evaluated as part of EPA's University-Based
Assessments Program. The plant uses heavy-density particle board, steel framing, rolls
and strips of sheet steel, Formica, and assorted hardware to produce wooden, wood with
steel frame, and steel furniture. To build the wooden units, Formica is laminated to the
raw board; the glued laminations are cured in a press; the laminated boards are cut,
drilled, and routed; and the units are partially assembled before packaging and shipping.
The wastes from these operations do not pose disposal problems.
CURRENT WASTE GENERATION & MANAGEMENT PRACTICES
The procedures employed to build the metal units create several wastes. 715
gal/yr of toluene sludge is generated from the cleaning of metal stock by dipping in a
toluene dip tank. This sludge is disposed off-site as a hazardous waste at a cost of
$8,230. 172 gal/yr of toluene is lost due to evaporation. Before the rnetal parts are
painted, they are cleaned. The cleaning process generates wastewater. After cleaning,
the metal parts are painted. The painting operation generates several waste streams.
Paint solids are combined with the wastewater from the cleaning operation yielding 7,515
gal/yr of wastewater. Spray-paint booths produce paint-laden air filters which collect
overspray. Annually, 832 filters are disposed. Approximately 3,390 gal of paint are lost
with the filters. 915 gal/yr of paint solvent are lost due to evaporation. Cleaning and
maintenance of the paint spray guns produces 55 gal/yr of toluene sludge and results in
44 gal/yr in toluene losses due to evaporation.
The plant is already investigating steam cleaning to eliminate the five-stage metal
cleaning operation. The use of dip painting has been minimized.
WASTE MINIMIZATION OPPORTUNITIES
The waste minimization opportunities concern the painting and toluene cleaning
operations. By installing an electrostatic powder coating system to replace the spray and
dip painting, not only will the parts be more evenly coated but there could be a 100%
reduction of evaporated paint solvent, paint-laden air filters, wasted paint, evaporated
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toluene, and paint solids. The annual savings would be $49,770, and the payback period
for the $145,880 implementation cost would be 2.9 yrs.
By protecting the clean metal stock from environmental dirt thus eliminating the
need for subsequent toluene dip-tank cleaning, 100% of the toluene sludge and
evaporated toluene could be eliminated. The annual savings would be $8,400, and the
payback period for the $3,800 implementation cost would be 0.5 yr.
By repairing the lid to the toluene dip tank to reduce evaporative loss and by
instituting a program to keep the lid closed when possible, 50% of the evaporated
toluene could be saved. The annual saving would be $180 by reducing the need to
replace evaporative loss, and the payback period for the $100 implementation cost would
be 0.5 yr.
By installing an electrostatic spray system in building 3 and reinstalling one in
building 4, the annual gallons of paint wasted would be reduced 29%. The annual savings
would be $39,880, and the payback period for the $66,900 implementation cost would be
1.7 yrs.
If the above waste minimization opportunities concerning the spray paint process
are not adopted, additional recommendations, not completely analyzed, are to:
Install a state-of-the-art dip paint line,
replace solvent-based paints with water-based paints, or
use air-tight spray-gun cleaning tanks to reduce toluene evaporation.
Research Brief Title: Waste Minimization Assessment for a Manufacturer of
Military Furniture
Research Brief Availability: March 1992
Assessment Responsibility: University of Tennessee Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
Key Words: military furniture; paint wastes; toluene
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MANUFACTURER OF COMMERCIAL ICE MACHINES
AND ICE STORAGE BINS
INTRODUCTION
A plant that annually manufactures 26,000 ice machines and 12,500 ice bins was
evaluated as part of EPA's University-Based Assessments Program. The raw materials
used in the various processes include galvanized and rolled steel sheets; brass; copper;
and metal treating and cleaning chemicals.
WASTE GENERATION & MANAGEMENT ACTIVITIES
The manufacturing processes, the wastes from the processes and their methods of
disposal and the annual amount and cost to dispose of the wastes are discussed below.
For cabinet components, galvanized and rolled steel sheets are cut, punched and
drilled. These sheets are then cleaned and rinsed. The wastewater (2,569,900 gal/yr)
from this process is pre-treated and then sewered at a cost of $4,320. The parts are then
coated with iron phosphate/phosphoric acid spray to serve as a base for the powder
coating. The wastewater (14,400 gal/yr) from this process is pre-treated and then
sewered at a cost of $30. The parts are rinsed to remove excess phosphating solution.
The wastewater (2,781,500 gal/yr) from this process is pre-treated and then sewered at a
cost of $4,680. Before finally being coated with paint powder and baked, the parts are
rinsed with chromate to provide a conversion coating. The rinse water (16,900 gal/yr)
containing hexavalent chromium is recycled and ion exchange treated. The material is
then sewered at a cost of $30.
For the flaker barrel, evaporator, and downchute assembly, after the brass tubes
are milled, drilled, threaded, wrapped around the barrel, and then cooled, the brass shell
is heated, shrink-fitted and brazed onto the assembly. The assembly is then sent through
a bright dip process for corrosion protection. The spent solution (660 gal/yr) of copper
sulfate and copper nitrate crystals is sent to the supplier who reclaims the copper at a
cost of $1,620. After rinsing and draining, assemblies undergo chemical sealant and rinse
treatments, including baths of soda ash, rinse, and sealant with isopropyl alcohol and
potassium hydride. The wastes generated from these steps (12,300 gal/yr) are pre-treated
and sewered. The finished barrel/evaporator assembly and the fabricated downchutes
are insulated with polyurethane foam. The spray nozzle used for the foam insulation is
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cleaned and the waste (170 gal/yr) is disposed of as a hazardous waste at a cost of
$1,770.
Separately, the evaporators undergo assembly. Copper parts are degreased and
dipped in a 5% hydrochloric acid solution. The waste from this step (20,800 gal/yr) is
pre-treated and sewered for $40. Eventually, the evaporator assemblies are cleaned in
an enclosed washer. Again the wastewater from this process (3,120,000 gal/yr) is pre-
treated and sewered at a cost of $5,240.
General plant wastes are generated during cleaning and maintenance operations.
Spent petroleum naphtha is reclaimed. Also, hydraulic and vacuum pump oil is
reclaimed. Sludge (18,200 gal/yr) is generated from on-site wastewater treatment
operations and is disposed of in a sanitary landfill at a cost of $6,300.
CURRENT WASTE MINIMIZATION PRACTICES
Presently, the plant already has:
replaced solvent-based paints with powder coatings;
installed a high-pressure foaming system to reduce organic cleaning wastes
in the bin-foaming area;
segregated excess metal for recycling by a scrap metal dealer;
developed preventive maintenance for metal-forming machinery;
recycled waste oils and spent bright dip solutions, solvents, and
ion-exchange cartridges;
employed a closed-loop rinse (just before powder coating) for ion-exchange
treatment; -reduced rinse-water flow rates to the lowest possible levels;
employed counterflow rinsing so the initial rinse used water from the
drainage collection tank;
employed a dead-rinse tank to collect drag-out in the bright dip process;
used drain boards following bright dip rinses;
dewatered wastewater treatment sludge;
replaced MEK with methylene chloride to clean foamer nozzles;
employed drip bars in degreasing bath and acid bath of small parts washer;
and
defined a formal waste minimization policy.
WASTE MINIMIZATION OPPORTUNITIES
When the metal cabinet components are cleaned and rinsed, the two rinses
generate well over 5 million gal of rinse water that are pre-treated and sewered. By
redirecting the rinsewater overflow from the second rinse (following the iron phosphate
treatment) to the first rinse, the fresh water used in the first rinse would be reduced by
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2,171,520 gal/yr. The savings would be $4,630/yr, and the payback period for the $800
implementation cost would be 0.2 yr.
The flaker barrel evaporator assemblies are cleaned in a bright dip line. By
cleaning these assemblies with a plastic media blasting unit, disposal of the spent
brightener and subsequent rinses could be eliminated as could the purchase cost of the
brightener. (The caustic bath, the sealer, and its rinse would then follow.) The waste
could be reduced by 9,960 gal/yr; the total savings could be $3,950/yr. The payback
period for the $5,000 implementation cost would be 1.3 yr.
Research Brief Title: Waste Minimization Assessment for A Manufacturer of
Commercial Ice Machines and Ice Storage Bins
Research Brief Availability: March 1992
Assessment Responsibility: Colorado State University Waste Minimization
Assessment Center
UCSC Reviewer: Gwen P. Looby
EPA Project Officer: Emma Lou George
Key Words: ice machine; ice storage bin; rinse water; chemical waste; bright dip
process; brass; steel; copper
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INDEX
acid 29, 30, 55, 56, 57, 59, 67, 80, 82, 83,
85, 91, 92
lead battery repair 29
sulfuric 29, 56, 80, 85
sulfuric anodizing system 6, 7
acrylic emulsions 58
adhesives 64, 65
ethylene-vinyl acetate 65
carrier vapor 65
administration building 44
aircraft 23, 35
C-9 medical 23
engines 19
fabrication 35
air conditioning 45, 48, 64, 67, 70
condensers, automotive 67
alcohol 10, 42
isopropyl 10
aliphatic hydrocarbons 42
alkaline washwater 26, 27
alloy 26, 27, 28
lead bearing lens blocking 26, 27
alternative paint application systems 48
aluminum 35, 64, 67, 70, 71, 76, 82, 85
parts 35
extrusion waste 82
cans 85
ammonium fluozirconate 85
anodizing 6, 7, 82, 83
antifreeze recycling 45, 46
aqueous waste 42
arsenate 87
copper 87
automated spray system 42
automatic shut-off 63
automotive 29, 30
subassembly rebuilding 29
parts cleaning 30
air conditioning condensers 67
B
bands, metal 79
bark 87, 88
bath regeneration 51
bath solution recovery 17
nickel plating 17
battery repair 29, 30
brass 91
brazing slurry 67, 68
bright dip process 91, 92
brightener 79, 93
bronze 83
Sandoz 83
buffing 82, 83
compound 82, 83
cascade rinse 56, 80, 81
centrifugation 51
chemical 1, 7, 8, 17, 19, 58, 59, 76, 79, 85,
91,
precipitation 17
substitution 7, 19
chlorofluorocarbons 45, 48
chromium 7, 8, 80, 91
clamps, metal 79
cleaner 44, 45, 52
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emulsion 35, 36
water-based 52
qualification performance 35
conveyorized 15
terpene-based 19, 20
cleaning 10, 11, 19, 20, 23, 24, 26, 27, 30,
44, 51, 52, 56, 57, 59, 62, 68, 70,
76, 77, 78, 79, 80, 81, 82, 87, 89,
90, 91, 92, 93
mechanical 51
parts 23, 24, 30
capabilities 19
lens 26, 27
metal 79, 80, 81, 89
cloth gowns 32
coating 37, 39, 41, 42, 51
water-based 42
bond 20
SealBrite 56
electrostatic powder 71, 89
cobalt 19
computer(ized) 3, 4, 6, 7, 8
printed circuit board plating system
3,4
sulfuric acid anodizing system 6, 7
hoist 4, 7, 8
-controlled robots 10
construction 38
continuous monitoring 17
copper 4, 50, 51, 55, 56, 57, 76, 82, 87, 91,
92
-recovery system 4
arsenate 87
creosote 87
cupric chloride solution 51
cutting oil 45, 67, 70
D
dairy waste 61, 63
deblocking 26, 27
degreasing(er) 15, 19, 15, 16, 24, 35, 67,
70, 71, 92
Safety-Kleen 24
vapor 35
solvent 15, 19
cold solvent 19
deionized water system 19, 20
developer 23, 24, 25, 50
silica-based 24
dewatering 51
disposables 32, 33
distillation 2, 15, 45, 46, 51, 71, 83
solvent 46
drying 42, 51
dry-off oven 60
dye penetrant 23
electric motor (DC) 76
electrical power generating plant 38
electrolytic equipment 51
electrostatic 10, 68, 71, 74, 77, 83, 89, 90
spray guns 10
powder painting 71, 77, 83, 89 62
paint spraying 74, 77
electrowinning 4
engraving 50, 51
epoxy powder 68, 76, 77
esters 42
etching 50, 51, 55, 56, 64
evaporators 67, 92
filtration 48, 51
forms 50
freon 14, 15, 48
recovery 14, 15
fume scrubbing 56, 67, 82, 83
furniture, military 89
glass lens 26, 27
ground glass fines 26
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H
high school 44, 45
health care 33, 34
heating 64
hemodialyzers 33
herbicides 58
hospital 32, 33
housekeeping 47
hydrocarbons 42
aliphatic 42
aromatic 42
hydroxide salts 17
I
ice 91
storage bin 91
machine 91
implants, orthopedic 19
incineration 10, 13, 15
infectious waste 32, 34
inks 51
water-based 51
solvent-based 51
inspections 23, 24, 40, 48
non-destructive wheel 23
inventory controls 39, 45
ion exchange 2, 4
J
K
ketone, methyl ethyl (MEK) 55, 67
lead acid battery repair 29
leather, finished 41
legal profession 50
lens 26, 27, 28
glass 26, 27
cleaning 26, 27
lime sludge 64
limonene 20
lumber, treated 87
M
magnet, permanent- 76
maintenance 37, 38, 39, 44, 47, 48, 49
activities 38
facilities 47
facility, transportation 47
market 33
materials 38, 39, 40, 41, 42, 44, 45, 47, 48,
49,51
surplus 38
handling procedures 47
medical 23, 26, 32, 33, 34
supply 32
waste 33
metal 55, 65, 70, 73, 76, 79, 80, 81, 82, 89,
90, 91, 92
bands 79
clamps 79
methanol 19, 20
methylene chloride stripping 13
microprocessor control 17
milk 61, 62, 63
mineral spirits 24
molecular sieve 10, 15
molybdenum parts 19
N
naval weapons systems 10
nickel plating 17, 18
nozzle, high-pressure 63
nuclear 38, 39
O
oil 39, 45, 47, 64, 65, 66, 67, 70, 71, 79, 85,
87, 92
recycling 47
No. 6 87
optical/computer interfaced system 42
optical fabrication 26
ordering procedures 38, 45
organic solvent 51
overspray 64, 65, 70, 73, 74, 77, 89
paint 74, 77
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paint 2, 9, 10,11,12, 13, 23, 24, 37, 39, 44,
45, 48, 64, 65, 67, 68, 70, 71, 73, 74,
77, 82, 83, 85, 89, 90, 91
booths 23, 70, 77, 89
chips 13, 73
guns, high-volume, low-pressure
(HVLP) 24
polyurethane 23
production operations 10
proportional mixer 10
sludge 24, 65, 71
solids 67, 70, 71, 77, 89, 90
stripping 2, 23, 24
thinner 24, 73
waste 45, 68, 77, 85, 90
water-based 48
alternative application system 48
perchlorethylene 70, 71
phosphate sludge 64, 65
photo processes 50
plasma spray deposition 19
plastic bead-blast(ing) 12, 13, 24
plating 2, 3, 4, 7, 17, 18, 79, 80
nickel 17, 18
zinc 80
primer 73, 74
printed circuit board 23, 55
manufacture 23
printing 37, 50, 51, 55, 56, 85
screen 55
procedures 38, 42, 45, 47
ordering 38, 45
warehouse 38
quality assurance 33
R
railcar rebuilding 73, 74
recovery 2, 4, 13, 14, 15, 17, 37, 45, 48, 50,
51
freon 14, 15
nickel plating bath solution 17
refrigerant 45
recycled washwater 30
recycling 1, 2,10, 15, 27, 29, 30, 37, 45, 46,
47,48
antifreeze 45, 46, 48
municipal 45
paint cleaning solvent 10
used tire 48
reprocessing 33
resins, low molecular weight 58, 59
reusable single-use devices 33
reverse osmosis 17
rinse(ing) 4, 7, 8, 17, 18, 20, 55, 56, 67, 71,
79, 80, 81, 83, 85, 91, 92, 93
eliminated tanks 4
on-demand 7, 8
water 55, 79, 80, 85, 91, 92, 93
robotic paint facility 9
scrap 70, 71, 76, 79, 80, 82, 85, 88, 92
separation 59, 73
separator 10, 15
silver 50
sludge 55, 56, 57, 59, 60, 63, 64, 65, 67, 68,
71, 73, 74, 76, 79, 80, 82, 83, 85, 87,
89, 90, 92
lime 64
phosphate 64, 65
solvent 39, 42, 45, 46, 51
capture system 42
distillation 46
polyurethane 10
spent Stoddard 26
stripping 24
source reduction 27
steel 35, 67, 70, 71, 73, 74, 76, 79, 80, 89,
91
stainless 79
substitution 27, 45
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T
thermal oxidizer 59
tire 48, 49
recycling 48
rotation 48
titanium parts 19
toluene 82, 83, 89, 90
tool manufacturing 79
transportation maintenance facility 47
trichloroethane 19, 67, 68, 70
trichloroethylene 35, 36
U
ultrasonic bath 19
V
vapor 35, 59, 65, 66
adhesive carrier 65
degreaser 35
ventilating 64
W
washwater, alkaline 26, 27
wastewater 55, 57, 59, 60, 62, 63, 67, 68,
71, 76, 80, 82, 83, 89, 91, 92
water consumption 7, 8
weapons 3, 6, 9, 10, 12, 14
naval 10
tactical defense 3, 6, 9, 12, 14
wood chips 87, 88
Wolmanizing 87
X
xylene 10
Y
Z
zinc 55, 57, 76, 79, 80, 82
plating 80
•U S. Government Printing Office: 1992— 648-003/41814
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