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ment has been superseded by the Facility Pollution Prevention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

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