United States
Environmental Protection
Agency
National Risk Management
Research Laboratory
Research Triangle Park, NC 27711
Research and Development
EPA/600/SR-96/075 July 1996
EPA Project Summary
Evaluation of Pollution
Prevention Opportunities for
Mold Release Agents
Jeffrey S. Lanning and Kevin A. Cavender
EPA's Air Pollution Prevention and
Control Division (APPCD) has assessed
the processes, materials, installation
practices, and emission characteristics
associated with the application of mold
release agents (MRAs). Emissions were
estimated based on available informa-
tion on MRA composition and con-
sumption. Volatile organic compound
(VOC) emissions of MRAs were esti-
mated to be 126,000 tons (114,000
tonnes) per year. The study also found
that polyurethane molding operations
accounted for a significant portion of
the total MRA emissions (about 25%)
and that automobile seat and other
foam molding operations accounted for
most of the emissions associated with
the polyurethane category. Thus, the
polyurethane foam manufacturing in-
dustry was selected for a pollution pre-
vention technology demonstration.
Several pollution prevention alterna-
tives were identified for conventional
MRA usage in the polyurethane foam-
ing industry. An initial assessment of
each of the identified technologies was
performed. APPCD selected the Sol-
vent Emission Reduction Technology™
(SERT™) process for further evalua-
tion. A detailed assessment of SERT
was made through a demonstration at
the Integram-St. Louis Seating polyure-
thane molding facility in Pacific, Mis-
souri. The demonstration evaluated the
applicability and technical barriers as-
sociated with the penetration of the
SERT process into the current MRA-
using infrastructure, the overall emis-
sion reduction potential, and the costs
associated with switching to the SERT
process. The demonstration showed
that a 60% reduction in VOC emissions
is readily attainable with this process
and that pollution prevention, e.g., the
SERT process) is a much more cost
effective way to reduce VOC emissions
than conventional treatment methods.
This Project Summary was developed
by EPA's National Risk Management
Research Laboratory's Air Pollution
Prevention and Control Division, Re-
search 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 and Background
Over the past several years, a new and
innovative approach to reducing hazard-
ous waste and emissions has been rap-
idly developing in the U.S. This new ap-
proach, called "pollution prevention," has
been defined by the U.S. Environmental
Protection Agency (EPA) as "the use of
materials, processes, or practices that re-
duce or eliminate the creation of pollut-
ants or wastes at the sources. It includes
practices that protect natural resources
through conservation or more efficient
use."
In the Pollution Prevention Act of 1990
(PPA), the U.S. Congress passed legisla-
tion to make pollution prevention a major
part of national environmental policy and
required the EPA to facilitate the adoption
of source reduction techniques by indus-
tries. Following the PPA, the U.S. Con-
gress passed the Clean Air Act Amend-
ments of 1990 (CAAA), which require the
EPA to establish a basic engineering re-
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search and technology program to de-
velop, evaluate, and demonstrate non-
regulatory strategies and technologies for
air pollution. In response to this legisla-
tion, the EPA published the Pollution Pre-
vention Strategy (56 FR 7849), which out-
lines EPA's pollution prevention goals and
sets forth a program to achieve specific
objectives. A key component of the pro-
gram outlined in the strategy is the estab-
lishment of a pollution prevention research
program to assist in the development,
evaluation, and demonstration of clean
products and clean technologies. One such
research program required the assess-
ment of emissions and pollution preven-
tion options for several consumer catego-
ries, including mold release agents.
The EPA's Air Pollution Prevention and
Control Division (APPCD) completed an
assessment of the processes, materials,
installation practices, and emission char-
acteristics associated with the application
of mold release agents (MRAs). Eleven
categories of industrial processes were
identified as consumers of MRAs. Emis-
sions estimates were developed based on
available information on MRA composition
and consumption for these 11 categories.
While the available data were limited, total
emissions from industrial mold release
agent use were found to be significant.
Volatile organic compound (VOC) emis-
sions for the 11 categories of MRA pro-
cesses were estimated to be 126,000 tons
(114,000 tonnes) per year (tpy). The study
also found that polyurethane molding op-
erations accounted for a significant por-
tion of the total MRA emissions (about
25%) and that automobile seat and other
foam molding operations accounted for
most of the emissions associated with the
polyurethane category.
The study concluded that automotive
and furniture seat cushion molding opera-
tions had the greatest opportunity for pol-
lution prevention. These operations were
identified because (1) their activity repre-
sents a significant fraction of the total na-
tional emissions associated with MRA us-
age, (2) processes related to MRA usage
do not vary significantly in the automotive
and furniture seat molding industries, mak-
ing it likely that a single pollution preven-
tion approach could be demonstrated that
would be broadly applicable, and (3) sev-
eral pollution prevention technologies at
various stages of development are appli-
cable.
Several pollution prevention alternatives
were identified for conventional MRA us-
age in the polyurethane foaming industry.
An initial assessment of each identified
technology was performed. This initial as-
sessment included potential to reduce
emissions of VOCs, technical feasibility,
and cost. Based on this preliminary evalu-
ation, the Solvent Emission Reduction
Technology™ (SERT™) process was se-
lected for further evaluation. A detailed
assessment of SERT was made through
a demonstration at the Integram-St. Louis
Seating polyurethane molding facility in
Pacific, Missouri. The demonstration evalu-
ated the applicability and technical barri-
ers associated with the penetration of the
SERT process into the current MRA- us-
ing infrastructure, the overall emission re-
duction potential, and the costs associ-
ated with switching to the SERT process.
Project Objectives and Scope
The purpose of this project was to iden-
tify pollution prevention options for the poly-
urethane foam molding industry. In addi-
tion, a demonstration of a best candidate
technology was planned. The demonstra-
tion was to show that an alternative mold
release system could be implemented into
a current manufacturing facility. The sys-
tem was to be evaluated on several key
issues, including technical feasibility, VOC
reduction, cost, worker acceptance, and
effects on production rate and quality. The
SERT process was compared to the con-
ventional MRA system in place at the
Integram facility. This system includes the
use of high-volume, low-pressure (HVLP)
spray guns. A detailed Quality Assurance
Project Plan was prepared, reviewed, and
approved in advance of the demonstra-
tion. This plan served as a guide through-
out the demonstration and data analysis.
Summary of Results
VOC Emissions and MRA
Usage
The SERT process proved to be effec-
tive at reducing MRA usage and thus VOC
emissions. Table 1 shows the amount of
MRA used and VOC released for each of
the 20 lots. MRA usage was reduced from
5 lb/100 parts (2.27kg/100 parts) to 2 Ib/
100 parts (0.91 kg/100 parts). This corre-
sponds to a decrease in VOC emissions
of 3 lb/100 parts (1.36 kg/100 parts), rep-
resenting a 63% reduction in VOC emis-
sions. For a plant producing 2.1 million
parts per year, the VOC reduction would
be 35 tpy.
Optimization of the system and training
of the sprayers would lead to even greater
reductions in VOC emissions. During the
study, it was determined that workers us-
ing the SERT system were spraying 30%
more solids than the workers using the
conventional MRA. Experience using this
system will help the workers determine
the proper amount of MRA to use, thus
reducing the amount of overspray. The
two spraying stations used in the study of
the conventional process were combined
into one for testing the SERT system.
One section of the mold was being sprayed
from beyond the optimum distance. This
may have led to additional overspray in
an attempt to compensate for the MRA
that was not reaching the mold. If the
system were optimized to equal the
amount of solids sprayed by the conven-
tional system, emissions reductions could
exceed 70%. This would correspond to a
40 tpy reduction in VOC emissions from a
plant such as the one in the demonstra-
tion.
Production Rate
The use of an alternative MRA can af-
fect the production rate in two ways. First,
production rate can be negatively impacted
if the alternative MRA has a longer appli-
cation time than the current MRA. Sec-
ond, the production rate can be impacted
if the alternative MRA has either a greater
or lesser amount of downtime due to mal-
functions or maintenance. Both the SERT
and conventional MRA were spray-applied
taking only a few seconds per part. The
MRA application step was not a limiting
factor with either technology. Downtime
was also monitored during the demonstra-
tion. The cause for each downtime was
determined to identify if the MRA were at
fault. During the tests, downtime averaged
less than 5 minutes per hour for both the
conventional and SERT processes. No
MRA related downtime was observed dur-
ing the demonstration for either technol-
ogy. Additionally, the number of parts
molded per hour per number of active
molds was determined for each lot. The
difference in the values for the SERT and
conventional processes was insignificant
(less than 2%). Based on these observa-
tions, it can be concluded that the SERT
process would not result in a significant
impact on production rate.
Product Quality
As in most industries, molded polyure-
thane foam must meet specific surface
qualities to ensure that the foam will be
adequate for its intended use. Poor sur-
face quality foams are often shredded for
other uses, such as carpet backing, thus
lowering the value to the manufacturer.
During the demonstration, surface quality
was evaluated by Integram's trained in-
spectors. Each molded part was initially
inspected following demolding. The foam
was allowed to finish curing and was then
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Table 1.
Summary of MRA Usage and VOC Emissions Measured During SERT
Demonstration
MRA
Type
Conventional
Run No.
1
2
3
4
5
6
7
8
9
10
Average
MRA Usage
(lb/100 parts)
6.1
6.0
4.0
8.3
6.8
4.9
2.9
4.4
3.5
3.4
5.0
VOC Emissions*
(lb/100 parts)
5.9
5.7
3.8
8.0
6.5
4.7
2.7
4.2
3.4
3.2
4.8
SERT High Solids
1
2
3
4
5
6
7
8
9
10
Average
Average Percent Reduction i
1.9
2.3
1.6
2.1
1.6
1.6
2.5
2.0
2.2
2.3
2.0
60
1.7
2.0
1.3
1.8
1.4
1.4
2.2
1.7
1.9
2.0
1.8
63
*MRA usage estimates do not include all three spray stations. Based on historical information
supplied by the test facility, the excluded station is esf/mated to contribute an additional 10% to the
total MRA usage.
evaluated by a final inspector. The in-
spectors examined the foam for defects
(i.e., tears, surface bubbles, and pore
structure defects) and rated the pieces of
foam on a pass/fail basis. There were no
MRA related defects for parts made by
either process. Based on the results of
the demonstration, it is concluded that the
SERT process would have no negative
impacts on the quality of the molded foam.
Worker A cceptance
A key issue in implementing any new
process is worker acceptance. If the work-
ers are uncomfortable with a process or
piece of equipment, overall performance
and quality may suffer. During the test,
the operators were asked for their opinion
of the SERT system. Half of the operators
were completely satisfied with the system
in its present state. The others recom-
mended minor changes to the system.
The most common recommendation was
the use of lighter, more flexible hoses and
a swivel at the base of the spray gun.
This would allow the operator more ma-
neuverability and could potentially reduce
overspray by giving the worker better ac-
cess to the part that needs to be sprayed.
The only other complaint voiced by the
workers was the "cloud" the system pro-
duced. This was simply the vaporization
of the carbon dioxide. By increasing the
maneuverability of the worker, worker ex-
posure to this "nuisance cloud" could be
avoided. From these interviews, the work-
ers appeared receptive to the SERT pro-
cess.
Cost Details
The costs associated with implement-
ing the new system were broken into two
groups, capital and annual. The total capi-
tal investment for four SERT stations in-
cluding freight, engineering, electrical im-
provements, and installation would be
$290,000. The total annual cost is
$164,000 (including operating costs of
$117,000 and capital recovery costs of
$47,000). The total annual cost for the
conventional MRA is $98,600 ($96,700
operating costs and $1,900 capital recov-
ery costs). From the total annual costs for
the new and conventional systems and
the VOC reduction, a cost effectiveness
value can be calculated. The cost effec-
tiveness for the SERT system is $1,870
per ton of VOC reduced. Several sce-
narios were generated by manipulating
conventional MRA price, number of SERT
stations required, and SERT MRA use
rate. The results of this sensitivity analysis
are presented in Table 2. The cost effec-
tiveness for scenarios involving four SERT
stations ranged from $1,090 to $2,390,
while it ranged from $440 to $1,110 if only
two stations were required.
Conclusions
The SERT process was found to be
effective at reducing VOC emissions dur-
ing the demonstration. On average VOC
emissions were reduced 63%. Industry-
wide, it was determined that 77% of the
VOC emissions are due to plants with
production greater than 4,000tpy. If SERT
was installed at large polyurethane plants
using solvent-based MRA and the same
VOC reductions were seen, VOC emis-
sions from the use of mold release agents
would decrease by 10,700 tpy. Addition-
ally, these VOC reductions were obtained
without loss of production or product qual-
ity.
The cost effectiveness value obtained
for the SERT process with four stations
was compared to standard add-on VOC
control measures. Thermal and catalytic
incinerators were chosen as the control
methods, since many polyurethane facili-
ties may not have the steam necessary to
regenerate carbon adsorbers. The incin-
erators were designed and costs deter-
mined by the methods described in the
OAQPS Control Cost Manual. The cost
effectiveness value for a thermal incinera-
tor was estimated at $8,040 per ton of
VOC not released, while the cost effec-
tiveness for the fixed bed catalytic incin-
erator was estimated at $6,440 per ton of
VOC not released. From these values, it
is clear that pollution prevention, (e.g., the
SERT process) is a much more cost ef-
fective way to reduce VOC emissions than
conventional treatment methods.
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Table 2. Sensitivity Analysis Results
Base Scenario 1
Number of
SERT
Units
MRA
Usage
Conventional
MRA Cost
TCI"
(SERT)
Operating
Costs
(SERT)
TACC
(SERT)
TAG
(Com.)
VOC
Decrease
Cost
Effectiveness
4
Measured
$5/gal *
$290,000
$117,000
$164,000
$98,600
35 tons "
$1,870/ton
4
Optimized
$5/gal
$290,000
$95,000
$142,000
$98,600
40 tons
$1,090/ton
Scenario 2a
4
Measured
$4/gal
$290,000
$117,000
$164,000
$80,400
35 tons
$2,390/ton
Scenario 2b
4
Measured
$6/gal
$290,000
$117,000
$164,000
$116,700
35 tons
$1,350/ton
Scenario 3 Scenario 4
2 2
Measured Optimized
$5/gal $5/gal
$161,000 $161,000
$111,000 $89,000
$136,900 $115,300
$97,900 $97,900
35 tons 40 tons
$1,110/ton $440/ton
'1 gal. =3.79L.
bTCI = Total capital investment.
CTAC = Total annual cost.
"1 ton = 907 kg.
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Jeffrey S. Lanning and Kevin A. Cavender are with Southern Research Institute,
Research Triangle Park, NC 27709.
J. Kaye Whitfield is the EPA Project Officer (see below).
The complete report, entitled "Evaluation of Pollution Prevention Opportunities for
Mold Release Agents," (Order No. PB96-187745; 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
National Risk Management Research Laboratory (G-72)
Cincinnati, OH 45268
Official Business
Penalty for Private Use $300
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT NO. G-35
EPA/600/SR-96/075
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