EP A/600/A-94/069
POLLUTION PREVENTION CONFERENCE ON
LOW- AND NO-VOC COATING TECHNOLOGIES
May 25 through 27, 1993
San Diego, California
Coleen M. Northeim and Ella J. Darden, Compilers
RESEARCH TRIANGLE INSTITUTE
P.O. BOX 12194
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27709
Sponsored by:
EPA Cooperative Agreement CR819541
EPA Project Officer: Michael Kosusko
AIR AND ENERGY ENGINEERING RESEARCH LABORATORY
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
Provided for:
VS. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH AND DEVELOPMENT
WASHINGTON, DC 20460

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POLLUTION PREVENTION OPPORTUNITIES
IN THE
MANUFACTURE OF PAINT AND COATINGS
BY
Paul M. Randall
US. Environmental Protection Agency
Office of Research & Development
Risk Reduction Engineering Laboratory
Pollution Prevention Research Branch
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
(513) 569-7673
FAX: (513) 569-7549
489

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Abstract
The paints and coatings industry is rapidly changing to meet environmental and
economic pressures. Some of the changes include new coating formulations, higher
performance finishes with improved properties, continued development of new technologies,
and new application methods with improved transfer efficiencies. In order to control costs,
improve productivity and quality, and protect the environment, more paint companies are
turning to pollution prevention as the cornerstone of their waste management programs. Paint
pollution prevention has been incorporated into many corporate tout quality management
(TQM) strategies.
There are many pollution prevention methods for the paint manufacturing industry
which vary from very simple, inexpensive measures to new, expensive plant/equipment. The
methods, techniques or programs can generally be classified as either recycling or source
reduction and may involve material substitution, process or equipment modification, revised
operating practices, operating procedures (such as waste stream segregation), personnel
practices (such as operator training), loss prevention practices, or accounting practices. This
paper will provide an overview of these practices in-place at particular manufacturing
facilities to reduce wastes and associated costs, to be a more competitive industry that must
still maintain quality and performance of its products.
The information in this article has not been subjected to Agency review. Therefore, it
does not necessarily reflect the views of the Agency.
Introduction
The role of the paint and coatings industry in the U.S. economy is pervasive. Paint
and coatings are essential not only for the decoration and protection of the surfaces of many
new industrial products but also for the maintenance of existing structures and products, such
as homes, vehicles, machinery and equipment, buildings and factories. Without these paint
and coatings, many of our durable and non-durable goods would have a decreased life-span.
The manufacture of paints and coatings is big business with shipments exceeding
Slli billion (1989) in the U.S. alone. Americans consume approximately 1 billion gallons
annually, of which, approximately SO percent is represented by architectural coatings. The
annual growth rate for the industry is expected to be 1 percent (1991-1996). The product
coatings area accounts for about 36% of (1991) shipments and special purpose coatings with
16% of 1991 shipments. The nine industries that are major consumers of paint and coatings
include: (1) automotive; (2) trucks/buses; (3) metal cans; (4) farm machinery/equipment; (5)
construction machinery; (6) coil coating; (7) wood furniture/fixtures; (8) metal
furniture/fixtures and; (9) household appliances.
The driving forces behind the changes in paints and coatings continue to be product
performance improvements and environmental regulations associated with new materials.
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Paint and coating formulators as well as upstream raw material and resin suppliers are
evaluating the components in their products and processes, changing the constituents to
achieve desired performance of their coatings while also meeting new environmental rales.
Paint producers undertake their own product research and development but also look to
technological leaders to meet reformulation needs.
In addition to addressing product reformulation impacts, paint and coatings
manufacturers are also examining their production methods to look for ways to control costs.
To achieve improved productivity and quality, as well as protect the environment, more paint
companies are turning to pollution prevention as the cornerstone of their waste management
programs. Pollution prevention methods generally involve material substitution, process or
equipment modification, modified operating practices and procedures (such as waste stream
segregation), personnel practices (such as operator training), loss prevention practices or
accounting practices. This paper will provide an overview of the paint industry's efforts to
reduce wastes and reduce costs, while at the same time provide quality paint and coatings
products which meet the performance requirements of a diverse customer base.
Review of Raw Materials
The primary raw materials used by the paint and coatings industry include resins,
pigments, solvents and additives. In the production of liquid paints (latex and solvent-based),
production methods are primarily physical, that is, there are no chemical reactions or
conversions of raw materials to other products and byproducts. Paint is typically a dispersion
of a finely divided pigment in a liquid composed of a resin or binder and a liquid vehicle.
There is a wide variety of synthetic resins used in coatings (i.e. acrylic, alkyd, vinyl,
epoxy, polyester, urethane, etc). The synthetic resins are long chain polymers that may be
linear, branched, or cross-linked or some combination of these forms depending on the
functionality and reactivity of the monomers from thick they are formed. Resins are selected
based on many factors but primarily on application and performance.
The liquid portion varies depending on whether the paint is solvent based or water-
based. Typical organic solvents include methyl ethyl ketone, methyl isobutyl ketone, toluene,
and xylene. Water based, water dispersed, or water soluble coating systems substitute water
for some or all of the volatile organic solvent.
Manufacturing Process Wastes
In the manufacture of paint and coatings, paint manufacturing facilities generate
different waste streams. Typical wastes include:
e Raw material packages, bags, containers from unloading materials into mixing vessels,
e Pigment dusts from unloading of pigments into mixing vessels
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e
Solvent emissions from storage tanks, leaks, and open process equipment
o
Off-spec paints
o
Spills
o
Riosewater from equipment cleaning using water or caustic solutions
o
Paint sludge from equipment cleaning operations
o
Filter cartridges with undispersed pigment, paint and/or resins.
Paint industries handle this waste by either on-site recycling, off-site recycling or
treatment/disposal. On-site recycling involves the selected reuse of raw materials or wash
materials in new batches of paints and coatings. Recycling of usable materials within the
plant reduces the amount of new virgin raw materials needed per batch, resulting in
significant reductions in operating aw well as waste management costs. On-site recycling of
solvents may include distillations. Many companies send their wastes to an off-site recycler,
though more and more of these companies are recycling their own wastes to reduce costs and
improve operating efficiencies. Treatment/disposal operations available to paint
manufacturers include incineration or land disposal. Typically, many paint manufacturers
send solvent-containing wastes off-site to a cement kiln for inclusion in a fuels-blending
program (for thermal destruction).
Of the wastes generated in a typical paint manufacturing facility, equipment cleaning
wastes are by far the largest in volume, collectively accounting for some 80% of the
industry's wastes. Process equipment and tanks are routinely cleaned to prevent product
contamination and/or restore operation efficiency. Equipment that may need cleaning include
high speed dispersion mixers, sand mills, colloid mills, rotary batch mixers and blenders,
drum mixers and roller, grinding equipment, mixing vessels, pumps & motors, filters and
strainers, filling and capping equipment and packaging equipment. Many paint manufacturers
are finding pollution prevention provides significant opportunities for reducing wastes.
Pollution Prevention Methods for the Paint Manufacturing Industry
Pollution prevention, or the method of preventing polluting through source reduction
and recycling, is becoming a cornerstone of most progressive waste management programs.
Reducing wastes to remain competitive has been an important ingredient for successful
business in the past and it will be absolutely essential in the future. So controlling and
optimizing all parts of the manufacturing process is critical to reduce costs, improve processes
and continue to be competitive and profitable.
Pollution prevention approaches can be broken down into the following categories:
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o Source reduction • Good manufacturing practices, production process changes,
and input material changes.
o Recycling - use and reuse of wastes, reclamation (on-site, off-site recovery).
Good manufacturing practices generally means better procedural or institutional
policies and practices and can include waste segregation, personnel/employee practices,
procedural measures, loss prevention practices, and accounting practices. Personnel practices
can include upper management initiatives, employee training, and/or employee incentives.
Careful attention to production and maintenance operations is important to reduce spills and
minimize off-spec products. Making employees more aware of the impact of waste on the
company's costs as well as the impact on the environment.
Procedural measures can include better documentation, better material and handling
storage, material tracking and inventory control and better production scheduling techniques.
For example, since thousands of different paint formulations require special production runs,
more effective planning and production scheduling may be needed. Paint production,
although a vital phase, must intermesh smoothly with purchasing, formulation sales,
accounting, inventory, personnel management etc. to make it profitable. Production planning
and scheduling may consist of a scheduling board listing the batches to be run on each piece
of equipment and the expected starting and finishing times. It aids maintaining adequate
inventory of active raw materials without overstocking and permits attainment of delivery of
commitments to customers. Also, if practiced effectively, it helps level peaks and slumps in
production during surges of short delivery orders or establish "downtime" of each piece of
equipment while keeping check of overall efficiency and ensuring maximum equipment
utilization.
In loss prevention practices, better awareness of spill prevention and in house
preventive maintenance programs may be required. Accounting practices should incorporated
better apportionment of waste management costs to the departments that generate wastes.
Most off-spec paint is generated by small shops that produce specialty paints. Since
the production costs for specialty paints are typically high, most off-spec paints are reworked
into marketable products. However, the cost of reworking off-spec paints are avoided if
better trained and supervised operators as well as quality control are reinforced so that
generation of off-spec paints are avoided.
Obsolete paint products and customer returns can be blended into new batches of
paint. Obsolete products result from changes in customer demands, new superior products,
and expired shelf life. Careful production planning and inventory control can reduce
obsolescence resulting from expired shelf life. Also marketing policies such as discounting
older paints can help reduce the amount of obsolete products.
There are many other ways of applying good manufacturing and operating practices.
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For example, soliciting employee suggestions may uncover methods to make changes
especially since the operators understand the process operations. Quality improvement teams
make significant improvements to the quality of the product, optimize the process, improve
efficiency and productivity, and reduce the wastes in the process. Furthermore, incentives,
rewards, and bonuses can be used to support pollution prevention programs and reduce
wastes.
Improving the efficiency of a process can significantly reduce waste generation.
Available techniques range from eliminating leaks from process equipment to installing state
of the art production equipment. This pollution prevention category includes improved
operation and maintenance, procedural changes, and equipment modifications.
Equipment cleaning wastes represents the largest source of waste in a typcial paint
plant. A method that reduces the need or frequency of tank cleaning or allow for reuse of the
cleaning solutions is the most effective way to reduce wastes.
The use of mechanical techniques, such as rubber wipers, reduces the amount of paint
left on the tank walls of a mix tank. Wipers are used to scrape the sides of a cylindrical mix
tank (flat or conical). Equipment cleaning is usually a manual operation so this process may
be justified based on rescued labor costs as well as reduced usage of cleaning solution
(another savings). High pressure spray heads and limiting wash/rinse time systems can be
used in place of regular hoses to clean water-based paint tanks. Studies show that high
pressure wash systems can reduce water use by as much as 80 to 90 percent.
Teflon line tanks are sometimes used to reduce wall adhesion and improve drainage.
This method is usually applicable to small batch tanks. A plastic or foam "pig" is used to
clean pipes. This pig device is forced through the pipe from the' mixing tanks to the filling
locations, using nitrogen or some other inert gas to propel the pig.
Manufacturing procedures may be improved. For example, a paint facility's wash
solvent from each solvent-based paint batch may-be separately collected and stored. When
the same type of paint is to be made, waste solvent from the previous batch is recycled and
used in place of virgin solvent.
Countercurrent rinsing processes can be applied to those plants with sufficient tanks
space. This technique is used to recycle "dirty" solution initially to clean tanks and then is
followed by a "clean" solution to complete the rinse cycle. The level of contamination builds
up more slowly with the clean solution than the dirty reused solution thus extending cleaning
solution life.
Spills due to accidental or inadvertent discharges usually occur during transfer
operations or as a result of equipment failure. For example, during a loading operation, a
spill may occur from a leaking fill hose or fill line connection or leaking valves, piping, and
pumps. Sometimes spills occur from overfilling of tanks or due to improper or
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malfunctioning overflow alarms. Improving regular equipment inspections and training
programs prevent these spills from occurring as well as improved instrumentation and
automation and efficient cleanup methods if spills do occur.
Small amount of dry materials used in paint may remain in bags. Capturing the
pigments for reuse through vapor traps helps reduce waste problems. The availability of
these materials in slurry or paste form eliminate problems of disposing of waste bags or
packages. Empty containers of liquid raw matenals that contain hazardous compounds are
typically cleaned or recycled back to the original raw materials manufacturers or to a local
drum recycler. This avoids the costs of disposing of the containers.
There are two major types of air emissions in paint manufacturing plants: VOCs and
particulates. VOCs may be emitted from the conservation vents on top of the bulk storage
tanks of resins and solvents and from the use of open processing equipment such as mix
tanks. Since most process equipment is of open design, reducing VOCs from equipment
could require substantial capital expenditure in retrofit costs. Closed vessels with overhead
refrigerated condensers will require considerable capital requirements which most paint
manufacturers cannot afford. In fixed roof design, maintained conservation vents, conversion
to floating roof, use of nitrogen blanketing to suppress emissions or the use of refrigerated
condensers. Implementing these options can result in cost savings to the paint and reduced
raw material losses.
Dusts generated during handling, grinding, and mixing of pigments may be hazardous
and therefore dust collection equipment such as hoods, exhaust fans, and bag houses are used.
Use of pigments in paste form instead of dry will reduce or eliminate dust generated from
pigments. The drums can be recycled.
v
Also, a major advance in paint manufacturing is the growing use of electronic control
devices and batch automation. The intent is to avoid operational accidents, improve quality,
and production efficiency, and the overall accuracy of the batch. The effect should be less
waste generated. Computer use is increasingly being used for materials allocation and
inventory control as well as preventive maintenance scheduling. As the costs associated with
plant automation equipment decreases, the use of automation in paint manufacturing facilities
will increase.
Case Studies
Four companies that have received special recognition for their pollution prevention
programs by industry are Moline Paint Manufacturing co. in Moline, IL, Vanex Color, Inc. in
Mt. Vemon, IL, Red Spot Paint & Varnish Co. in Evansville, IN, and Jamestown Paint
Company in Jamestown, PA. Moline reported a 50% reduction of hazardous wastes in less
than 6ve years and reported savings of over S140,000/yr in disposal and raw materials costs.
Moline's program included on site recovery for reuse, process modifications, statistical
process control techniques of waste generation, improved housekeeping, employee
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participation, and reuse of hazardous wastes off-site in a waste-to-energy recovery program.
Vanex Co. used source reduction and recycling methods. Ethylene glycol, a free-
thaw stabilizer in latex paints, has been replaced with propylene glycol which exhibits less
health concerns. Wash solvents generated from the production of solvent-based paints is
recycled, when possible, into subsequent solvent-based paint batches. Unusable wash solvent
was sent to a cement kiln. Approximately 80% of all wash solvent was recycled in-house
resulting in savings of S15,000/yr.
Red Spot Paint Sl Vamish Co. initiated a full waste-tracking system to identify the
exact point of origin of each unit process waste, which was then sampled and analyzed to
determine its potential for recycling and reuse. The program concentrated on motivating
employees to become more waste conscious and to train them in waste reduction methods and
procedures. Through their program, the company saved more than SI million by incorporating
a number of seemingly insignificant equipment additions and a few equipment and tool
modifications, which represented over 60% savings.
Jamestown Paint Company incorporated pollution prevention into their total quality
management (TQM) program by focusing on waste minimization, quality control, customer
satisfaction and increased profitability. Employees drawn from various operational and
administrative areas formed process improvement teams, and each team was given specific
objectives and charged with clearly defined improvement goals. Results a year after
implementation of the program showed a reduction in hazardous waste by more than 75% and
savings in excess of $100,000.
Pollution Prevention Techniques Applicable to Paint Manufacturing
The following summarizes some of the pollution prevention techniques paint
manufacturers are using:
Source Reduction
° Schedule compatible solvents in sequence to reduce truck loading and drum flushing
need.
° Schedule like colors through equipment.
° Install dedicated lines where feasible to reduce flushing.
° Segregate line and pump flushings to produce low-grade thinners suitable for cleaning
purposes.
° Equip bulk storage tanks with vapor return lines.
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e Instill collector to remove pigment dust from manufacturing area.
o Increase drum inventories of high volume products to reduce changing of products in
the drumming line.
o Replace wastewater treatment lagoons with new system incorporating concrete cells
covered by fiberglass dome, equipped with venting of off-gases to destruction by
burning.
o Eliminate dry bags by convening to titanium dioxide slurry system pumped directly to
mixer.
o Install closed filtration systems to reduce VOC emissions (losses); also closed filter
systems can eliminate residues once left in filter bags.
o Install odor/vapor capture systems on bulk solvent storage tanks, resin tanks and
manufacturing tanks.
e Eliminate all obsolete materials for possible rework.
Reuse/Recycling in manufacturing process
o Recycle wash solvent whenever possible; to facilitate recycling, setup holding tanks
for recovered washwater and wash solvent, segregate by color and/or product Hoe;
reuse wash solvents from one batch in the grind state of the next batch of the same
formula.
o Collect pigment dust and recycle into batches.
o Reuse in batch production solvents used for cleaning sand mills, manufacturing tanks,
and tankwagons.
o Reuse obsolete materials in present production.
o Use virgin solvent for taakwagon cleaning and reuse to subsequent production.
o Pass vapors generated during filling and manufacturing through filters to remove as
much VOCs as possible; collect solvent that would otherwise have gone to atmosphere
and use as wash solvent
o Where possible, mix obsolete colors and sell as undercoat or primer.
e Accumulate ail skids not usable at plant and give to skid vendor.
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o Recycle used motor oil from company vehicles.
o Reuse cardboard shipping cartons and plastic pails; return comer boards on can
shipments to supplier.
o Unrecyclable wash solvents can be used as supplemental fuel in cement kilns for
energy recovery; establish contracts with cement kilns for recycling of unusable wastes
with high BTU value.
o Inspect, repair, and reuse shipping pallets received with the purchase of raw materials
or return to vendor.
o Rinse and crush metal containers and ship to scrap metal recycler.
° Recondition and recycle drums and five-gallon pails for use.
Conclusions
The paints and coatings industry will continue to seek new technologies to meet the
growing needs and demands of our society. While there has been significant progress in the
industry to reduce or eliminate waste, manufacturers of all coatings recognize that new
environmental regulations may seek to significantly reduce their wastes even further. As a
result, paint manufacturers will increasingly turn to pollution prevention techniques and
methods to eliminate waste generation. Already, pollution prevention methods are making
significant contributions to reduce paint wastes/sludges through source reduction,
process/production techniques, good manufacturing practices, and material substitutions. The
coatings industry's efforts will be important towards improving environmental quality. Many
of the pollution prevention techniques developed by the paint industry are relatively simple
and inexpensive and may only require a conscious change in operating procedures. Some
changes such as new plant/equipment require greater monetary expenditures up front, but in
the long run, may provide the company with significant cost savings and improved
environmental quality.
Conclusions in this article are those of the author. No official support for these
conclusions by the U.S. EPA is intended or should be inferred.
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For Further information
There are rainy pollution prevention methods which have been published in various
literature or can be obtained through industry contacts. For further information, please
contact:
° Paul Randall
U.S. Environmental Protection Agency
Office of Research Sl Development
Risk Reduction Engineering Laboratory
26 W. Martin Luther King Drive
Cincinnati, Ohio 45268
Ph. No. 513/569-7673
FAX 513/569-7549
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TECHNICAL REPORT DATA
(Pleate read Instructions on the reverse before completing
	
1 REPORT NO. 2.
EPA/600/A-94/069
3 RE
4 TITLE and subtitle
POLLUTION PREVENTION OPPORTUNITIES IN THE MANUFACTURE
OF PAINT AND COATINGS
5 REPORT DATE
6. PERFORMING organization COOE
7. AUTHOR(S)
Paul M. Randall
8. PERFORMING ORGANIZATION REPORT NO.
9 PERFORMING ORGANIZATION NAME AND ADDRESS
Risk Reduction Engineering Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
10. PROGRAM ELEMENT NO.
1 1. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND AOORESS
Risk Reduction Engineering Laboratory-Cin., OH
Office of Research and Development
U.S. Enviornmental Protection Agency
Cincinnati, OH 45268
13. TYPE OF REPORT AND PERIOO COVERED
Conference presentation
14. SPONSORING AGENCY CODE
EPA/600/14
is supplementary notes Proceedings of the Pollution Prevention Conference on
Paul M. Randall 513/569-7673; Lot and No-VOC Coatings, May 25-27, 1993, San Diego,
CA. d:489-499
16. ABSTRACT
The paints and coatings industry is rapidly changing to meet environmental
and economic pressures. Some of the changes include new coating formulations,
higher performance finishes with improved properties, continued development of new
technologies, and new application methods with improved transfer efficiencies. In
order to control costs, improve productivity and quality, and protect the
environment, more paint companies are turning to pollution prevention as the
cornerstone of their waste management programs. Paint pollution prevention has
been incorporated into many corporate total quality management (TQM) strategies.
There are many pollution prevention methods for the paint manufacturing
industry which vary from very simple, inexpensive measures to- new, expensive
plant/equipment. The methods, techniques or programs can generally be classified
as either recycling or source reduction and may involve material substitution,
process or equipment modification, revised operating practices, operating
procedures (such as waste stream segregation), personnel practices (such as
operator training), loss prevention practices, or accounting practices. This
paper .will provide an overview of these practices in-place at particular
manufacturing facilities to reduce wastes and associated costs, to be a more
competitive industry that must still maintain quality and performance of its
product.
17. KEY WORDS AND DOCUMENT ANALYSIS
3. DESCRIPTORS
b.identifiers/open ended terms
c. COSATl Field/Croup
pollution prevention
paints
coatings
waste minimization
paint manufacturing
recycling
source reduction


18. DISTRIBUTION STATEMENT
Release to Public
19. security Class (Tim Reportt
Unclassified
21. no. of pages
13
20 SECURITY CLASS (This pc$t)
Unclassified
22. PRICE
EPA ftm 2220-1 (R»». 4-77) pocviou* coition ii omouite

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