United States
Environmental Protection
Agency
Risk Reduction
Engineering Laboratory
Cincinnati, OH 45268
Research and Development
EPA/600/S-94/019 September 1994
&EPA ENVIRONMENTAL
RESEARCH BRIEF
Waste Minimization Assessment for a Manufacturer
of Parts for Truck Engines
Richard J. Jendrucko*, Kelly Binkley*, Todd Thomas*, Stephanie Wilson*,
Eric W. Daley**, and Gwen P. Looby**
Abstract
The U.S. Environmental Protection Agency (EPA) has funded
a pilot project to assist small and medium-size manufacturers
who want to minimize their generation of waste but who lack
the expertise to do so. In an effort to assist these manufactur-
ers Waste Minimization Assessment Centers (WMACs) were
established at selected universities, and procedures were
adapted from the EPA Waste Minimization Opportunity As-
sessment Manual (EPA/625/7-88/003, July 1988). That docu-
ment has been superseded by the Facility Pollution Prevention
Guide (EPA/600/R-92/088, May 1992). The WMAC team at the
University of Tennessee performed an assessment at a plant
that manufactures turbochargers, fan drives, and vibration damp-
ers for truck engines. Metal castings are machined and cleaned;
degreased, coated and/or painted, if required; and assembled,
inspected, packaged, and shipped. The team's report, detailing
findings and recommendations, indicated that the plant could
achieve significant cost savings by replacing its solvent-based
painting system with an electrostatic powder coating system,
thereby reducing paint overspray.
This Research Brief was developed by the principal investiga-
tors and EPA's Risk Reduction Engineering Laboratory, Cincin-
nati, OH, to announce key findings of an ongoing research
project that is fully documented in a separate report of the
same title available from University City Science Center.
Introduction
The amount of waste generated by industrial plants has be-
come an increasingly costly problem for manufacturers and an
additional stress on the environment. One solution to the prob-
* University of Tennessee, Department of Engineering Science and Mechanics.
* University City Science Center, Philadelphia, PA.
lem of waste generation is to reduce or eliminate the waste at
its source.
University City Science Center (Philadelphia, PA) has begun a
pilot project to assist small and medium-size manufacturers
who want to minimize their generation of waste but who lack
the in-house expertise to do so. Under agreement with EPA's
Risk Reduction Engineering Laboratory, the Science Center
has established three WMACs. This assessment was done by
engineering faculty and students at the University of
Tennessee's WMAC. The assessment teams have consider-
able direct experience with process operations in manufactur-
ing plants and also have the knowledge and skills needed to
minimize waste generation.
The waste minimization assessments are done for small and
medium-size manufacturers at no out-of-pocket cost to the
client. To qualify for the assessment, each client must fall
within Standard Industrial Classification Code 20-39, have gross
annual sales not exceeding $75 million, employ no more than
500 persons, and lack in-house expertise in waste minimiza-
tion.
The potential benefits of the pilot project include minimization
of the amount of waste generated by manufacturers and re-
duction of waste treatment and disposal costs for participating
plants. In addition, the project provides valuable experience for
graduate and undergraduate students who participate in the
program and a cleaner environment without more regulations
and higher costs for manufacturers.
Methodology of Assessments
The waste minimization assessments require several site visits
to each client served. In general, the WMACs follow the proce-
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dures outlined in the EPA Waste Minimization Opportunity
Assessment Manual (EPA/625/7-88/003, July 1988). The WMAC
staff locate the sources of waste in the 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 tech-
nological and economic information is developed. Finally, a
confidential report that details the WMAC's findings and recom-
mendations (including cost savings, implementation costs, and
payback times) is prepared for each client.
Plant Background
The plant manufactures turbochargers, fan drives, and vibra-
tion dampers for truck engines. It operates approximately 6,000
hr/yr to produce more than 600,000 units annually.
Manufacturing Process
The major raw materials used by the plant are iron, aluminum,
magnesium, and steel castings. Manufactured parts purchased
by the plant include bearings, finger sleeves, bands, studs, and
rubber strips.
For the production of turbochargers, steel castings undergo a
vapor degreasing operation and friction welding. In parallel
operations, the steel, aluminum, and iron castings are turned,
drilled, tapped, and sent through an alkaline cleaner. The
finished parts are assembled into complete turbocharger units,
packaged, and shipped.
In the fan drive production line, aluminum, magnesium, iron,
and steel castings are turned, drilled, and tapped, resulting in
rotors, shafts, and bearing housings. Rotors are sandblasted,
vapor degreased, spray-coated with a wear-resistant formula-
tion, and heated in a curing oven. The shafts and bearing
housings, after an alkaline cleaning, are assembled with the
finished rotors. The finished product is packaged and shipped.
To produce dampers, iron castings are first turned, drilled, and
tapped. The parts are cleaned and conveyed through a sec-
ondary phosphate etchant. After heating, the parts are primed,
coated with rubber, heated again, cleaned, painted, and cleaned
again. Finished parts are assembled, packaged, and shipped.
An abbreviated process flow diagram for this plant is shown in
Figure 1.
Existing Waste Management Practices
This plant already has implemented the following techniques to
manage and minimize its wastes:
Onsite solvent recovery units are used to distill spent
degreasing solvent for reuse.
Several waste streams, including an anti-rust treatment and
cleaning chemicals, have been eliminated from the produc-
tion process.
A heat pump evaporator has been purchased for drying of
wastewater sludge.
Waste cardboard is baled and sold to a recycler.
Waste metals are compacted into blocks and sold as scrap.
Waste Minimization Opportunities
The type of waste currently generated by the plant, the source
of the waste, the waste management method, the quantity of
the waste, and the annual waste management cost for each
waste stream identified are given in Table 1.
Table 2 shows the opportunities for waste minimization that the
WMAC team recommended for the plant. The minimization
opportunity, the type of waste, the possible waste reduction
and associated savings, and the implementation cost along
with the simple payback time are given in the table. The
quantities of waste currently generated by the plant and pos-
sible waste reduction depend on the production level of the
plant. All values should be considered in that context.
It should be noted that the financial savings of the minimization
opportunities result from the need for less raw material and
from reduced present and future costs associated with waste
management. Other savings not quantifiable by this study in-
clude a wide variety of possible future costs related to chang-
ing emissions standards, liability, and employee health. It also
should be noted that the savings given for each opportunity
reflect the savings achievable when implementing each waste
minimization opportunity independently and do not reflect du-
plication of savings that would result when the opportunities
are implemented in a package.
Additional Recommendations
In addition to the opportunities recommended and analyzed by
the WMAC team, two additional measures were considered.
These measures were not analyzed completely because of
insufficient data, implementation difficulty, or a projected lengthy
payback. Since one or more of these approaches to waste
reduction may, however, increase in attractiveness with chang-
ing conditions in the plant, they were brought to the plant's
attention for future consideration.
Reduce the frequency of leaks and spills of hydraulic oil.
Dispose of spent coolant through a method other than the
onsite wastewater treatment plant.
This research brief summarizes a part of the work done under
Cooperative Agreement No. CR-914903 by the University City
Science Center under the sponsorship of the U.S. Environmen-
tal Protection Agency. The EPA Project Officer was Emma
Lou George.
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Metal castings
Metal castings
Metal castings
I
Vapor degreasing
Welding
Machining
Cleaning
Assembly
Turbo-chargers shipped to customers
Fan drives shipped to customers
Dampers shipped to customers
Figure 1. Abbreviated process How diagram for truck engine parts manufacture.
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Table 1. Summary of Current Waste Generation
Waste Generated
Source of Waste
Waste Management Method
Annual Quantity
Generated (Ib)
Annual Waste
Management Cost1
Rejected metal castings
Metal chips
Wastewater (contains coolant,
alkaline cleaner, iron phos-
phate cleaner)
Evaporated perchloroethylene
Perchloroethylene still bottoms
Spent hydraulic oil
Metal grindings and spent
grinding wheels
Steam-washer sludge
Spent powder abrasive
Evaporated "Genesolv"
"Genesolv" still bottoms
Unusable Teflon dust
Evaporated mineral spirits
Spent mineral spirits
Residual primer mixture
Residual adhesive
Evaporated toluene
Evaporated methyl ethyl ketone
Paint overspray
Paint containers
Paint filters
Evaporated thinner
Cardboard
Filters
Waste oil
Inspection of raw materials
Machining operations
Machining operations,
cleaning operations,
etching
Vapor degreasing
Onsite recovery unit
Machining operations
Grinding of parts
Cleaning of production equipment
Sandblasting
Vapor degreasing
Onsite recovery
Overspray from coating operation
Parts cleaning
Parts cleaning
Painting
Overspray from adhesive application
Primer application
Adhesive application
Painting
Painting
Paint spray booths
Painting
Disassembly of returned parts
Wastewater treatment plant
Wastewater treatment plant
Returned to supplier
Compacted into blocks; sold to recycler
Treated in onsite wastewater
treatment plant; sewered
Evaporates to plant air
Shipped offsite as hazardous waste
Shipped offsite as hazardous waste
Shipped to landfill
Shipped offsite as hazardous waste
Shipped to landfill
Evaporates to plant air
Shipped offsite as hazardous waste
Shipped to landfill
Evaporates to plant air
Shipped offsite as hazardous waste
Shipped offsite as hazardous waste
Shipped offsite as hazardous waste
Evaporates to plant air
Evaporates to plant air
Shipped offsite as hazardous waste
Sold to reclaimer
Shipped offsite as hazardous waste
Evaporates to plant air
Baled; sold to recycler
Shipped to landfill
Shipped offsite as hazardous waste
102,800
398,772
3,046,080
12,580
740
23,080
12,000
6,000
8,000
13,400
590
880
1,470
4,400
6,600
550
13,725
1,100
1,000
1,440
30
7,130
24,000
180
27,950
$0
-15,450
118,820
4,780
1,380
1,660
1,610
16,450
810
22,520
2,170
2,180
560
5,130
16,450
1,660
0
0
7,530
1,310
2,980
0
1,390
6,080
2,020
11ncludes waste treatment, disposal, and handling costs and applicable raw material costs.
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Table 2. Summary of Recommended Waste Minimization Opportunities
Annual Waste Reduction
Minimization Opportunity
Waste Reduced
Quantity (Ib)
Percent
Net Annual
Savings
Implementation
Cost
Simple
Payback (yr)
Reuse treated water from the onsite
wastewater treatment facility for
mopping and equipment washdown.
Discharged water should be monitored
for zinc and if the permitted threshold for
that constituent is exceeded, the water
should be treated accordingly.
Install an electrostatic powder paint
coating system to replace the solvent-
based spray paint booths used
currently.
Install a small distillation unit for the
onsite recovery and reuse of spent
mineral spirits. A small quantity of
still bottoms will be generated and
shipped offsite if this opportunity is
implemented.
Fabricate and utilize conveniently re-
movable, lightweight corrosion-
resistant plastic covers for the
vapor degreasers to reduce evapor-
ative losses.
Wastewater
431,600
Residual primer mixture
Paint over spray
Paint containers
Paint filters
Spent mineral spirits
Evaporated Genesolv
Evaporated perchloroethylene
6,600
1,000
1,440
30
4,400
6,664
6,290
14
$2,340
$10,900
4.7
100
100
100
100
100
59,030
4,430
46,260
13,320
0.8
3.0
50
50
13,650
440
0.1
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United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
EPA/600/S-94/019
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