United States
Environmental Protection
Agency
National Risk Management
Research Laboratory
Cincinnati, OH 45268
Research and Development
EPA/600/SR-97/101
November 1997
&EPA Project Summary
Powder Coat Applications
Michael J. Docherty and Fred J. Mulkey
Abstract
Powder coating is an organic finish-
ing technology that offers users the
potential to reduce volatile organic com-
pound (VOC) emissions to zero. Due to
ever-increasing VOC emission restric-
tions placed on manufacturers, pow-
der coating production and use has
been growing dramatically over the past
few years. Powder coating has been
accepted by such manufacturing com-
munities as automotive, appliance, fur-
niture, and equipment. However, small
business manufacturers have difficulty
investigating new technologies due to
size and budget restrictions. Through
the Environmental Protection Agency's
(EPA) Environmental Technology Ini-
tiative, the National Defense Center for
Environmental Excellence (NDCEE),
operated by Concurrent Technologies
Corporation (CTC), has worked with a
small business representative to dem-
onstrate the applicability of powder
coating for small business. During the
project, critical factors that affect the
environment, cost, quality, and produc-
tion were investigated. The investiga-
tion demonstrated that powder has the
potential to provide unique and valu-
able benefits when considering each
of these areas.
This Project Summary was developed
by the National Risk Management Re-
search Laboratory's Air Pollution Pre-
vention and Control Division, Research
Triangle Park, NC, to announce key
findings of the research project that is
fully documented in a separate report
of the same title (see Project Report
ordering information at back).
Introduction
New environmental regulations are plac-
ing tighter and tighter restrictions on how
manufacturers can coat parts. A nominal
reduction in VOCs can be achieved by
such equipment technologies as higher-
efficiency spray equipment like High-Vol-
ume, Low-Pressure (HVLP) and electro-
static equipment. In addition, a process
material change can reduce VOC emis-
sions by eliminating them from formula-
tions. Coatings manufacturers offer a range
of low-VOC technologies to lower emis-
sions such as high-solids paint, water-
borne, and powder coating materials.
Powder coating, invented in the early
1950s, is an environmental technology with
zero-VOC emissions. Although powder
coatings have been in existence for over
40 years, they have not gained widespread
acceptance until recently with the intro-
duction of strict VOC emission regulations.
Powder coating manufacturers have con-
tinually refined their formulations and offer
coatings that match or exceed performance
characteristics of previously used liquid
spray coatings.
Although powder coating has been
adopted by such large industries as auto-
motive, appliance, and furniture manufac-
turing, small businesses often do not have
the resources to investigate new technolo-
gies. In order to successfully transition a
new technology, a company must be able
to investigate all aspects of the new pro-
cess that affect:
• cost,
• environmental impact,
• part quality, and
• production.
Once these areas are evaluated, an
informed decision can be made regarding
the implementation of new technology.
The EPA, through its Environmental
Technology Initiative, has funded the
NDCEE to work with small businesses to
demonstrate powder coating and identify
opportunities for its use by these busi-
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nesses. Ideally, the project would result in
powder coating's being implemented by a
small business manufacturer.
The project focused on commercially
available powder coating materials that
could potentially be implemented into small
business manufacturing. These powder
coatings have been developed for and
used by larger manufacturers and the De-
partment of Defense (DOD), but also have
similar performance characteristics to
those required by smaller businesses.
Procedure
Collaboration with the EPA, the DOD,
the Small Business Association (SBA), and
the Powder Coatings Institute (PCI) iden-
tified candidate small businesses for di-
rect participation in the Powder Coating
Applications project. The basic require-
ment was that small business candidates
had to be using solvent-based liquid fin-
ishing technologies as a major compo-
nent of their manufacturing process with
an interest in transitioning to powder coat-
ing technology. One such small business
representative, The Bilco Company, uses
a solvent-based primer to coat its prod-
ucts.
To establish a baseline for the process
economics, technical requirements and
environmental aspects for The Bilco
Company's current parts finishing opera-
tion, an on-site facility survey was con-
ducted. This was followed by a detailed
questionnaire which was used by Bilco
representatives to assess current opera-
tions, and follow-up telephone conversa-
tions with Bilco personnel. This informa-
tion was used to prepare the final life-
cycle cost, environmental, and technical
performance comparative analyses of the
present finishing process to the powder
coating alternative process.
Prior to full-scale powder coating tech-
nology demonstrations and formal eco-
nomic and product performance data col-
lection, it was necessary to perform initial
feasibility testing to determine if powder
coating technology was appropriate for the
parts manufactured by The Bilco Com-
pany. The primary objective was to dem-
onstrate that powder-based coatings show
promise in terms of coating performance
data for meeting Bilco's existing primer
requirements.
To accomplish the feasibility assess-
ment, various Bilco parts and sample cou-
pons were pretreated and powder coated.
Initial powder coating conditions were es-
tablished through best engineering judg-
ments, lessons learned from short dura-
tion pretreatment/powder coating runs, and
performance requirements/information ob-
tained from The Bilco Company and the
suppliers of the pretreatment chemicals
and powder coatings.
Following pretreatment and powder
coating, various laboratory coatings tests
were performed on the powder-coated
Bilco parts and sample coupons to deter-
mine the degree of compliance to Bilco's
current coating performance specifications.
Parallel laboratory tests were also per-
formed on sample coupons coated at The
Bilco Company using their current liquid
coating process to establish the actual
product quality of this coating system. This
comparison indicated that a substantial
increase in performance could be gained
by using powder coating.
Following the successful feasibility dem-
onstration of powder coating applied to
Bilco parts, an optimization trial was per-
formed. The optimization phase was in-
tended to:
• focus on those aspects of the powder
coating process that demonstrated a
need for further refinement based on
process engineering lessons learned
and/or laboratory testing results from
the feasibility trial,
• demonstrate that Bilco's coating re-
quirements could be maintained after
optimization process changes were
made, and
• serve as a technical preparation phase
for the final technology validation dem-
onstration trials.
To accomplish the optimization testing
phase of the project, powder coating runs
were performed on Bilco parts and sample
coupons. Following the coating of these
specimens, a series of laboratory coat-
ings tests were performed.
Following completion of the optimiza-
tion testing, a final powder coating valida-
tion demonstration was conducted. The
goals of the validation testing were to:
• use the process parameters and les-
sons learned from prior trials, and
prove-out the ability of powder coat-
ing technology to successfully coat
Bilco parts under simulated produc-
tion conditions,
• to make any final process engineer-
ing observations which would trans-
late into powder coating process tran-
sition recommendations, and
• to collect "on-line" technical, economic,
and quality data for the powder coat-
ing of Bilco parts.
The validation demonstration was
achieved by performing a simulated pow-
der coating work day specific to the pow-
der coating of Bilco parts. Laboratory prod-
uct performance testing was used to verify
continued compliance to Bilco's coating
specifications.
Results and Discussion
Environmental analysis of the alterna-
tive powder coating, demonstrated the po-
tential to eliminate VOC emissions. Cur-
rently, approximately 39 tons (35 metric
tons) per year of VOCs are produced by
the current system. These VOCs are sent
to a catalytic incinerator destruction sys-
tem that is nearing the end of its useful
life and will need to be replaced in order
to meet regulations if the current coating
system is kept. This VOC destruction sys-
tem reduces the amount of VOCs emitted
into the atmosphere to 2.5 tons (2.3 met-
ric tons) per year.
During quality analysis, powder coating
demonstrated the potential to dramatically
improve upon performance of the current
coating system. Performance characteris-
tics such as salt spray corrosion resis-
tance, impact resistance, and hardness
were improved with the use of powder
coating. With increased coating perfor-
mance, Bilco could investigate the possi-
bility of offering an extended warranty on
its products.
Powder coating systems can be de-
signed to meet Bilco's present and future
production requirements. Automatic and
manual powder equipment presently ex-
ists that can be configured to meet Bilco's
present 235 door/day production level.
Using the National Institute of Standards
and Technology (NIST) Building Life Cycle
Cost program with a study period of 15
years, it was calculated that, through pow-
der coating, Bilco can save over $142,000
each year in operating costs when com-
pared to using the current coating system
with increased VOC controls. In addition,
a Life Cycle Cost savings of over $280,000
can be obtained with powder.
Bilco's current finishing system, flow
coating, is a high-transfer efficiency coat-
ing process resulting in a low cost per
part. As a result, it is estimated that an
investment in powder coating equipment
will not realize payback until year 7 after
investment. This payback period is much
longer than observed when powder sys-
tems have replaced liquid spray coating
technologies in industry. However, ben-
efits such as increased part quality and
reduced use of hazardous materials are
difficult to quantify. Powder coating, while
offering a payback period of 7 years, has
the potential to increase product quality
and provide a cleaner, healthier workplace.
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M. DochertyandF. Mulkeyare with Concurrent Technologies Corp., Johnstown, PA
15904.
J. Kaye Whitfield is the EPA Project Officer (see below).
The complete report, entitled "Powder Coat Applications," (Order No. PB98-
108624; Cost: $21.50, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Air Pollution Prevention and Control Division
National Risk Management Research Laboratory
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use $300
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EPA
PERMIT No. G-35
EPA/600/SR-97/101
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