&EPA
United States
Environmental Protection
Agency
Research and Development
Risk Reduction
Engineering Laboratory
Cincinnati, OH 45268
EPA/600/S-92/040 Oct. 1992
ENVIRONMENTAL
RESEARCH BRIEF
Waste Reduction Activities and Options for a
Manufacturer of Paints Primariiy for Metai Finishing
Patrick Eyraud and Daniel J. Watts*
Abstract
The U.S. Environmental Protection Agency (EPA) funded a
project with the New Jersey Department of Environmental
Protection and Energy (NJDEPE) to assist in conducting waste
minimization assessments at 30 small- to medium-sized busi-
nesses in the state of New Jersey. One of the sites selected
was a facility that produces paints primarily intended for metal
finishing. A site visit was made in 1990 during which several
opportunities for waste minimization were identified. These
opportunities include improved solvent handling techniques,
reuse of some solvent washing wastes, and changes in equip-
ment washing techniques. Implementation of the identified waste
minimization opportunities was not part of the program. Percent
waste reduction, net annual savings, implementation costs and
payback periods were estimated.
This Research Brief was developed by the Principal Investiga-
tors and EPA's Risk Reduction Engineering Laboratory in Cin-
cinnati, OH, to announce key findings of this completed as-
sessment.
Introduction
The environmental issues facing industry today have expanded
considerably beyond traditional concerns. Wastewater, air
emissions, potential soil and groundwater contamination, solid
waste disposal, and employee health and safety have become
increasingly important concerns. The management and dis-
posal of hazardous substances, including both process-related
wastes and residues from waste treatment, receive significant
attention because of regulation and economics.
* New Jersey Institute of Technology, Newark, NJ 07102
As environmental issues have become more complex, the
strategies for waste management and control have become
more systematic and integrated. The positive role of waste
minimization and pollution preventbn within industrial operations
at each stage of product life is recognized throughout the
world. An ideal goal is to manufacture products while generat-
ing the least amount of waste possible.
The Hazardous Waste Advisement Program (HWAP) of the
Division of Hazardous Waste Management, NJDEPE, is pursu-
ing the goals of waste minimization awareness and program
implementation in the state. HWAP, with the help of an EPA
grant from the Risk Reduction Engineering Laboratory, con-
ducted an Assessment of Reduction and Recycling Opportuni-
ties for Hazardous Waste (ARROW) project. ARROW was
designed to assess waste minimization potential across a
broad range of New Jersey industries. The project targeted 30
sites to perform waste minimization assessments following the
approach outlined in EPA's Waste Minimization Opportunity
Assessment Manual (EPA/625/7-88/003). Under contract to
NJDEPE, the Hazardous Substance Management Research
Center at the New Jersey Institute of Technology (NJIT) assisted
in conducting the assessments. This research brief presents
an assessment of a manufacturer of paints primarily for metal
finishing (1 of the 30 assessments performed), and provides
recommendations for waste minimization options resulting from
the assessment.
Methodology of Assessments
The assessment process was coordinated by a team of techni-
cal staff from NJIT with experience in process operations,
basic chemistry, and environmental concerns and needs. Be-
cause the EPA waste minimization manual is designed to be
primarily applied by the inhouse staff of the facility, the degree
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of involvement of the NJIT team varied according to the ease
with which the facility staff could apply the manual. In some
cases, NJITs role was to provide advice. In others, NJIT
conducted essentially the entire evaluation.
The goal of the project was to encourage participation in the
assessment process by management and staff at the facility.
To do this, the participants were encouraged to proceed through
the organizational steps outlined in the manual. These steps
can be summarized as follows:
• Obtaining corporate commitment to a waste minimization
initiative
• Organizing a task force or similar group to carry out the
assessment
• Developing a policy statement regarding waste minimiza-
tion for issuance by corporate management
• Establishing tentative waste reduction goals to be achieved
by the program
• Identifying waste-generating sites and processes
• Conducting a detailed site inspection
• Developing a list of options which may lead to the waste
reduction goal
• Formally analyzing the feasibility of the various options
• Measuring the effectiveness of the options and continuing
the assessment.
Not every facility was able to follow these steps as presented.
In each case, however, the identification of waste-generating
sites and processes, detailed site inspections, and development
of options was carried out. Frequently, it was necessary for a
high degree of involvement by NJIT to accomplish these steps.
Two common reasons for needing outside participation were a
shortage of technical staff within the company and a need to
develop an agenda for technical action before corporate com-
mitment and policy statements could be obtained.
It was not a goal of the ARROW project to participate in the
feasibility analysis or implementation steps. However, NJIT
offered to provide advice for feasibility analysis if requested.
In each case, the NJIT team made several site visits to the
facility. Initially, visits were made to explain the EPA manual
and to encourage the facility through the organizational stages.
If delays and complications developed, the team offered assis-
tance in the technical review, inspections, and option develop-
ment.
The Paint Manufacturer
The facility is a producer of paints, used primarily in the metal
finishing industry including automobile refinishing applications.
This business requires production of a large variety of colors
and finish types, most in relatively small quantities. The specifi-
cations of their customers allow a very narrow range of variation
in color and appearance of the finished product. This severely
limits the flexibility the company has in changing production
processes.
The production of the various types of paints is conceptually
very simple. Required operations include mixing and blending
(under carefully specified conditions) raw materials either pur-
chased from vendors or shipped from other company sites. No
manufacturing of paint constituents takes place at this facility.
After formulation and blending, the paints are transferred to a
variety of containers for shipment to the customer. The pro-
cessing equipment is cleaned prior to preparation of the next
batch. The cleaning operation typically includes multiple rinses
with solvent in order to remove the pigments and additives
remaining from the previous batch.
Paint production uses a solvent or liquid carrier to dissolve or
suspend the components of the coating system. This process
is a large user of solvents. At present, the preponderance of
the solvents used in these applications are organic. However,
there is a trend In the coatings industry toward water-based
products where customer demands and product performance
criteria are met. The technology for water-based coatings has
not been sufficiently advanced to address all such demands
and performance requirements. Therefore, solvent-based paints
and coatings will be required for some time.
The company has already instituted a program of pollution
prevention. This is perhaps best illustrated by the acquisition
and use of a large capacity still which allows recovery and
reuse of the solvents from the equipment washing operations.
Other pollution prevention efforts have been carried out in
conjunction with the corporate research and development group.
This lead to the reduction or elimination of the use of heavy
metal-containing dyes and pigments in products produced by
this facility.
Waste Streams and Existing Waste
Management
This particular facility presents a challenge in describing waste
streams. The presence of an operating solvent recovery sys-
tem means that the actual waste streams sent offsite are
relatively insignificant in terms of the total effluent from the
process before the solvent distillation. Moreover, where there
is a significant level of air emissions to be addressed, the
meaning of the term "treatment and disposal costs" has to be
strained to include simple loss of the value of materials.
The major RCRA waste from this facility is the still bottoms
from the recovery/recycling/reuse of waste solvents from the
equipment washing process. About 250 drums of this material
are produced annually from the facility and are sent offsite for
disposal. This quantity represents 10% to 20 % of the volume
of waste solvents which were sent for disposal prior to the
installation of the distillation equipment.
Another waste stream results from quality control samples of
finished batches which are retained at the facility for a period of
time for examination if customer problems or complaints come
in about specific batches of paint. After the retention period,
the samples are discarded as hazardous waste. Approximately
one quart size samples are collected and retained. The typical
current practice is to recover the solvent from these retained
samples through the solvent recovery system. There was no
information available on the number of these samples gener-
ated and retained each year.
Another waste stream identified was a waste oil stream from
equipment maintenance and repair. This stream averages 3 to
4 drums per year and is sent offsite for recycling and recovery.
The greatest pollution prevention challenge at this facility is not
RCRA-type waste streams. Rather it consists of stack emis-
sions and fugitive air emissions. SARA Title III reporting and
additional estimates indicated that approximately 200,000 Ib of
solvent are emitted to the atmosphere annually. The facility
intends to address this situation using a pollution prevention
approach.
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Summary of Waste Minimization Opportunities
The type of waste currently generated by the facility, the
source of the waste, the quantity of the waste and the annual
treatment and disposal costs are given in Table 1.
Table 2 shows the opportunities for waste minimization recom-
mended for the facility. The type of waste, the minimization
opportunity, the possible waste reduction, the net annual sav-
ings, and the implementation cost along with the payback
times are given in the table. The quantities of waste currently
generated at the facility and the possible waste reduction
depend on the level of activity of the facility. All values should
be considered in that context.
It should be noted that the economic savings of the minimiza-
tion opportunities in most cases result from the need for less
raw material and from reduced costs associated with waste
treatment and disposal. It should also be noted that the savings
given for each opportunity reflect the savings achievable when
implementing each waste minimization opportunity indepen-
dently, and do not reflect duplication of savings that would
result when the opportunities are implemented in a package.
Also, no equipment depreciation is factored into the calcula-
tions.
The decision to add solvent distillation capabilities at the facility
significantly reduced the volume of waste shipped from the site
for treatment. It did, however, engender a new waste stream at
the site. These still bottoms present a particular challenge from
a waste reduction perspective: to minimize the still bottoms
stream. Some possible options include: identification of benefi-
cial uses for the still bottoms; recovery of valuable materials
from the bottoms; and change in operating practices to reduce
the quantity and type of materials which appear in the still
bottoms.
In the absence of specific information about the content of the
still bottoms (which would be variable at best), it is not possible
to suggest specific options regarding beneficial uses for this
material. Similarly, it is not possible to discuss specific options
for recovery of valuable materials from the bottoms. These
questions can be effectively addressed after data about the
composition of the still bottoms is collected.
In general, it is assumed that the materials in the still bottoms
consist of residues which are contained in the solvents as they
enter the facility, product residues from equipment rinsing and
cleaning, and manufacturing residues from disposal of products
or raw materials. Modification of equipment rinsing and clean-
ing practices to reduce the amount of solids in the rinses would
result in a decrease in the quantity of solids in the still bottoms.
One approach which may accomplish some of this objective
would be to segregate washings from equipment used for
transfer of raw materials from washings of equipment used for
finished batches. These washings would then be distilled
separately. Such segregation and distillation of raw material
solutions should result in concentrated solutions of the raw
materials which could be used in production, rather than as a
component of still bottoms for disposal.
The majority of the still bottoms result from washing of equip-
ment from the finished batches of coatings. The best opportu-
Table 1. Summary of Current Waste Generation
Waste Generated Source of Waste
Still Bottoms Residue from solvent recovery
and recycling
Waste Oil Obtained from equipment maintenance
and repair
VOC Emissions Fugitive and stack emissions
of solvents used throughout
the facility
Annual Quantity
Generated
250 drums
4 drums
200,000 Ib
Annual Waste
Management Costs
$65,000
$130
$40,000
(This cost represents
the estimated value of
the solvents lost to the
atmosphere.)
Table 2. Summary of Waste Minimization Opportunities
Waste Stream
Reduced
Minimization Opportunity
Still Bottoms Segregation and recovery of
concentrates from washings
of raw materials for reuse.
Reprocessing of retained samples
VOC Emissions Develop and institute program of
leak detection and correction.
Reevaluate manufacturing processes
in light of pollution prevention
goal.
Annual Waste Reduction Net Implementation Payback
Quantity Percent Annual Savings Cost Years*
5 drums
1 drum
180,000 Ib
2%
0.5%
90%
$3,100
$325
$36,000
$1,000
$0
$150,000
(It should be recognized that a program
such as tiiis is a multi-year effort
so the total cost will not be incurred in
any single year.)
0.3
immed
4.2
* Savings result from reduced raw material, and treatment and disposal costs when implementing each minimization opportunity independently.
•&U.S. GOVERNMENT PRINTING OFFICE: 1994 - 550-067/80152
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nity for reduction of this component lies in scheduling of batches
in terms of colors and coating types. If appropriately sched-
uled, less rinsing may be required, particularly in moving from
lighter colors to darker colors. On the other hand, it must be
recognized that this facility has very tight specifications for
color reproducibility because many of their customers do color
matching. From a total pollution prevention perspective, it may
be preferred to thoroughly rinse the equipment and collect the
resulting still bottoms rather than risk the potential disposal of
an entire batch of paint.
For impact on emission reduction, attention should be given to
the sources of the emissions and on the potential options for
emission reduction. As indicated previously, more than 200,000
Ib of SARA 313 emissions are reported annually from this
facility. Approximately 70% of this total amount represents
fugitive air emissions. The material emitted in largest quantity
is acetone, representing about 50% of the fugitive air emis-
sions and about 48% of the total emissions from the facility.
Before developing a slate of options for addressing this chal-
lenge, the company examined the question of how such large
losses could have been accepted for so many years. All of the
manufacturing operations met the company standards for ma-
terial use, therefore there was no reason to question the
quantity of materials purchased and the quantity which actually
went into the product.
Upon further questioning about how the company manufactur-
ing standards were determined, it was concluded that when the
product was first manufactured, careful records were kept and
maintained for the first three or four batches. These records
included information about materials used. Then with the addi-
tion of a slight margin for error, these quantities became the
manufacturing standard. This means that whatever procedures
were used in the past which may contribute, in this case, to
elevated levels of fugitive emissions are perpetuated unless
new questions are raised by an "outside" process such as this
one.
The list of volatile chemicals which make up the fugitive air
emissions consists of the solvents which are used in the
manufacture of the coating products at the facility. In addition,
acetone is used as a solvent for equipment cleaning. This
provides two different avenues to be explored for pollution
prevention options. The solvent used in direct production is
essentially fixed in terms of how much solvent must be in the
product shipped to the customers, therefore any reduction in
emissions from this part of the operation must result from
changes in losses from spills and leaks, incomplete transfers,
and evaporation.
Because much of the material flow in the facility is a mecha-
nized movement from large storage tanks to production ves-
sels, there are opportunities for leaks at seals and connections.
A high priority option could be to check the entire solvent
supply system for leaks. Based upon experiences at other
facilities, particular attention should be given to seals and to
pumps. Regular inspection for such leaks should be a part of
the program.
There are also opportunities for evaporative losses when the
production vessels are being filled and operated. Certainly, air
displacement is necessary in the tanks to allow proper filling.
The ability to cap the tanks and use of a vapor recovery
system with a condenser could have a significant impact upon
evaporative losses. Depending upon the quality of such con-
densate, it could be returned directly to the production vessel
resulting in an immediate reduction in total material used for
each batch. Alternatively, the recovered solvent could be sent
to the distillation process for purification prior to reuse.
Evaporative losses can also occur during the filling operations
for the containers which go to the consumers. A contained
process for this filling operation to allow for solvent recovery by
condensation could be investigated. Alternatively, revised filling
procedures with smaller container openings to reduce evapo-
rative surfaces would reduce fugitive air emissions from this
source. Process engineering and design efforts will be required
in order to address these options.
This Research Brief summarizes a part of the work done under
cooperative Agreement No. CR-815165 by the New Jersey
Institute of Technology under the sponsorship of the New
Jersey Department of Environmental Protection and Energy
and the U.S. Environmental Protection Agency. The EPA Project
Officer was Mary Ann Curran. She can be reached at:
Pollution Prevention Research Branch
Risk Reduction Engineering Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
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