United States
Environmental Protection
Agency
Risk Reduction
Engineering Laboratory
Cincinnati, OH 45268
Research and Development
EPA/600/S-93/007 September 1993
&EPA ENVIRONMENTAL
RESEARCH BRIEF
Waste Minimization Assessment for a Manufacturer
of Baseball Bats and Golf Clubs
Marvin Fleischman*, F. William KirscIV
J. Clifford Maginn, Jr.**
and
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. Waste Minimization Assessment Cen-
ters (WMACs) were established at selected universities and
procedures were adapted from the EPA Waste Minimization
Opportunity Assessment Manual (EPA/625/7-88/003, July 1988).
The WMAC team at the University of Louisville performed an
assessment at a plant manufacturing baseball bats and golf
clubs — approximately 1,500,000 bats/yr and 550,000 golf
clubs/yr. To make the bats, wood billets are oven-dried and
machined to a standard dimension. After sanding they are
branded and finished. The golf clubs are made by finishing and
assembling purchased heads and shafts. Cast heads, forged
heads, persimmon-wood heads and stainless steel shafts are
used. The cast heads are ground and finished, then driven
onto the shafts. The forged heads are bored for the shaft,
ground, milled, polished, nickel-plated and pressed onto the
shafts. The persimmon-wood heads are drilled for the shaft,
fitted with a brass back plate and an aluminum soleplate,
stained, finished and bonded to the shafts. Grips, labels and
shaft bands are applied to the shafts, which may be coated
with polyurethane. The team's report detailing findings and
recommendations, indicated that the most waste, other than
rinse water discharged to the publicly owned treatment works
(POTW) and wood turnings which are sold, consists of scrap
cardboard and paper from the shop and offices, and that the
greatest savings, including new income, could be obtained by
segregating the cardboard and paper wastes for sale to a local
recycler.
University of Louisville, Department of Chemical Engineering
University City Science Center, Philadelphia, PA 19104
This Research Brief was developed by the principal investiga-
tors and EPA's Risk Reduction Engineering Laboratory (RREL),
Cincinnati, OH, to announce key findings of an ongoing re-
search 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
problem of waste 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 formation of waste but who lack the
inhouse expertise to do so. Under agreement with EPA's
RREL, the Science Center has established three WMACs.
This assessment was done by engineering faculty and stu-
dents at the University of Louisville's WMAC. The assessment
teams have considerable direct experience with process op-
erations in manufacturing 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 inhouse expertise in waste minimiza-
tion.
Printed on Recycled Paper
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The potential benefits of the pilot project include minimization
of the amount of waste generated by manufacturers, reduced
waste treatment and disposal costs for participating plants,
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-
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 produces baseball bats and golf clubs. The plant
operates 2040 hr/yr to produce approximately 1,500,000 bats/
yr and 550,000 golf clubs/yr.
Manufacturing Process
To make the bats, white ash billets are oven dried, cut to a
standard length and turned in a lathe to a standard dimension,
sanded, branded and finished. The golf clubs are made by
finishing and assembling cast, forged or persimmon-wood heads
and stainless steel shafts. The raw materials include wood
billets, water-based stains, tape for grips, investment casting
heads, forged stainless steel heads, persimmon wood heads,
stainless steel shafts, paint, epoxy adhesive, labels, reagent
chemicals for nickel and chrome plating, brass back plates,
aluminum sole plates, shellac, stains, filler, and sealant, primer
and polyurethane coatings.
The following steps are involved in making the bats:
• White ash billets are oven-dried, cut to length, turned
in a lathe to a standard dimension, and sanded smooth.
• The bats are burn-branded, foil-branded or silk-
screened with a logo and specified markings, then
finished with water-based stain and topcoat.
• Waste wood cutting shavings, sawdust and sanding
dust are collected and sold for use in particle board.
Spent stain filters are discarded for landfill disposal,
and stain rinse water is discharged to the POTW.
Mylar film from foil branding is discarded for landfill
disposal, and spent solvent from washing silk screens
is shipped for disposal as hazardous waste.
An abbreviated process flow diagram for baseball bat manu-
facturing is shown in Figure 1.
These steps are involved in making iron golf clubs:
• Investment casting heads (purchased) are ground and
polished to the proper weight, sanded, paint filled and
Wood
billets
Oven
drying
Sanding
Cutting
Lathing
Silk-screening
or foil-branding
Shipped to
customers
Figure 1. Abbreviated process flow diagram for baseball bat
manufacturing.
driven onto the shaft. An epoxy adhesive is used for
bonding. Tape is applied to each club for the grip, and
self-adhesive labels are applied as shaft bands.
Forged heads (purchased) are first bored for the shaft
and ground to obtain a flat face. Score lines are
pressed into the face, the back of the head is milled,
and the heads are ground to proper weight.
After vibratory polishing, the forged iron heads are
nickel-plated, sandblasted, chrome-plated, and pressed
onto the shafts. (Stainless heads are not plated.) The
clubs are then finished in the same manner as those
with cast heads.
Metal dust from grinding and polishing and chips from
boring and milling are shipped offsite for disposal.
Spent solvent from paint cleanup and naphtha used in
applying the grips are shipped offsite for disposal as
hazardous waste. Worn rags are discarded as non-
hazardous waste. Sludge from vibratory polishing is
dewatered and discarded for landfill. The water sepa-
rated is recirculated or discharged to the POTW.
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Spent cleaner solution and rinse water, neutralized
spent acid pickling solution, and nickel and chrome
plating rinse waters are discharged to the POTW.
An abbreviated process flow diagram for iron golf club manu-
facturing is shown in Figure 2.
These steps are involved in making persimmon-wood clubs:
• A nose and neck piece are cut from the persimmon-
wood heads, which are then sanded, drilled and ta-
pered for the shaft. A slot is milled in the face for a
plastic insert, and a slot is milled in the back for a
brass back plate. An aluminum sole plate is added
with a layer of epoxy.
• The heads are polished, faces are coated with mask-
ing shellac, and hot stain is applied for color. Filler is
applied twice. The heads are then wiped with rags
and sanded to proper dimensions, removing the shel-
lac.
• Metal surfaces are cleaned with steel wool, and wiped
with naphtha. A sealer and primer are applied and
oven cured.
~ rurcnasea
forgings
Boring and
reaming
^—
Grinding
^—
Machining
— ^
Nickel
plating
-^
Polishing
Chrome
plating
Point-
filling
Cutting
Packaging
Shipped to
customers
Finishing
Attaching
_
• Shafts are epoxy-bonded to the heads, grips are ap-
plied, and polyurethane topcoat is sprayed on and
oven cured. Whipping is applied to the necks, and
bands are applied to the shafts.
• Stainless steel shaft cuttings, brass cuttings, and alu-
minum cuttings are sold for scrap. Spray booth car-
tridge filters, when spent, are discarded for landfill.
Existing Waste Management Practices
• Vibratory polishing sludge is dewatered before dis-
posal as landfill.
• A fume suppressant is used in chrome plating, and
plating tank hood exhausts are scrubbed before vent-
ing.
• The paint and coating spray booth exhaust is filtered
before venting.
Waste Minimization Opportunities
The type of waste currently generated by the plant, the source
of the waste, the quantity of the waste, and the annual man-
agement costs are given in Table 1.
Table 2 shows the opportunities for waste minimization that the
WMAC team recommended for the plant. The type of waste,
the minimization opportunity, the possible waste reduction and
associated savings, and the implementation cost along with the
payback time are given in the table. The quantities of hazard-
ous waste currently generated by the plant and possible waste
reduction depend on the production level of the plant. All
values should be considered in that context.
It should be noted that, in most cases, the economic savings of
the minimization opportunities result from the need for less raw
material and from reduced present and future costs associated
with hazardous waste treatment and disposal. Other savings
not quantifiable by this study include a wide variety of possible
future costs related to changing emissions standards, liability,
and employee health. It should also be noted that the savings
given for each opportunity reflect the savings achievable when
implementing each waste minimization opportunity indepen-
dently and do not reflect duplication 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, several additional measures were consid-
ered. These measures were not analyzed completely because
of insufficient data, implementation difficulty, or a projected
lengthy payback as indicated below. Since one or more of
these approaches to waste reduction may, however, increase
in attractiveness with changing conditions in the plant, they
were brought to the plant's attention for future consideration.
• Separate the components of waste metal dust for
sale. The cost of separation was found to be too
large.
• Eliminate plating wastes by sending the work to a
commercial plating shop. Increasing use of stainless
steel golf clubs will reduce the need for plating, but a
shop capable of the needed high quality plating was
not found.
Figure 2. Abbreviated process How diagram for golf club manufac-
turing.
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Reduce overspray wastes by monitoring the spray
coating techniques in use for possible improved effi-
ciency. Data were not available for further analysis.
Use dibasic esters (DBE) in place of acetone for
cleanup. DBE has a lower evaporation rate and gen-
erates no hazardous waste. It might also substitute for
MEK or naphtha in some applications and can be
reclaimed by vacuum distillation. Data were not avail-
able for further analysis.
Reduce solvent evaporation by use of containers that
are covered or close automatically and by reducing
the amount of solvent applied to rags for cleaning.
Data were not available for further analysis.
Re-use spent naphtha for cleaning. The clarity of the
spent naphtha indicated that it could be used again.
Data were not available for further analysis.
Use water-based inks for silk screening so the screens
can be cleaned with aqueous cleaners, eliminating
the generation of hazardous solvent waste. The pos-
sibility of increased BOD levels in the wastewater
must also be considered. Data were not available for
further analysis.
Consider alternative disposal of spent solvents. Lower
disposal cost would be expected for burning the waste
in a fuels program, or if the individual solvent compo-
nents can be recovered. Data were not available for
further analysis.
This Research Brief summarizes a part of the work done under
Cooperative Agreement No. CR-814903 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. She can be reached at:
Pollution Prevention Research Branch, MS 466
Risk Reduction Engineering Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
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Table 1. Summary of Current Waste Generation
Waste Generated
Source ot Waste
Annual Quantity
Generated
Annual Waste
Management Cost
Wood scrap, wood chips and sawdust
Dumpster waste
Metal dust
Stainless steel cuttings
Aluminum and brass cuttings
Vibratory polishing sludge
Spent colored lacquer
Combined spent solvents
Spent cutting oil and lube oil
Spent nickel stripping solution
Spent rinse water
Solvent vapor losses
Wood wastes are pulverized, 3,300,000 Ib
collected in a vacuum dust collector,
and sold for use in particle board.
Scrap paper and cardboard, 939,000 Ib
spent filters, mylar film and worn
rags are disposed of as landfill.
Dust from grinding and polishing 11,700 Ib
golf club heads is disposed of
as landfill.
Cuttings from golf club shafts 2,000 Ib
are sold as scrap.
Cuttings from golf club head sole 110,000 Ib
plates and backs are sold as scrap.
After settling and decanting, sludge 1,815 gal
from polishing is dewatered off-site
and disposed of as landfill.
Spent lacquer from baseball 110 gal
bat staining is disposed of as
hazardous waste.
Spent solvent from cleaning parts 4,430 gal
and machinery is disposed of
as hazardous waste.
Spent oil from machining and 275 gal
lubrication is disposed of as
hazardous waste.
Spent solution from stripping 55 gal
nickel plating is concentrated and
disposed of as hazardous waste.
Water from plating rinse, bat coating 2,424,000 gal
rinse and vibratory polishing is
neutralized for pH control and
discharged to POTW.
Fugitive and stack emissions of solvent 3,997 gal
vapors are lost to the atmosphere.
($12,430)1
10,932
2,148
(60)1
(3,000)1
2,210
280
11,100
700
290
3,175
10,992
' The annual waste management cost is shown as negative because this waste stream generates revenue for the plant when sold.
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Table 2. Summary of Recommended Waste Minimization Opportunities
Annual Waste Reduction
Waste Generated
Minimization Opportunity
Quantity
Percent
Net Annual Implementation Payback
Savings Cost Years
Dissolved nickel
anode chips
Scrap cardboard
and paper
Combined spent
solvents
Vibratory polishing
sludge
Nickel anode chips are to be removed
from the plating bath when it is not in use.
This will extend their life.
Cardboard and paper wastes
are to be segregated and
sold to a recycler.
Spent solvents are to be segregated
at their sources and recovered by
distillation.
Use a hydroclone to dewater the sludge
to 70% solids before shipping off site
for disposal.
Unknown 0
930,000 Ib 100
3,402 gal 90
935 gal 52
$2,684 0 0
31,500 0 0
21,817 $11,440 0.5
1,490 6,207 4.2
Paint overspray and
spent filter
Used cleaning rags
Paint overspray
and spent filters
Paint several golf club heads on a rack, 148 gal 33
instead of individually, for
improved efficiency.
Used rags are 7,058 Ib 75
to be laundered and re-used
Paint golf club heads with an 202 gal 80
air-assisted spray for improved
efficiency.
3,365 900 0.3
2,823
4,589 5,600 1.2
&U.S. GOVERNMENT PRINTING OFFICE: 19*3 - 7SO-O7I/80WW
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