Wiping
Case Studies
The John Roberts Company in Minneapolis, MN is a commercial printer. They had been using a solvent
containing TCA for handwiping press blankets between printing jobs. The leased towels were then returned to a
commercial laundry for cleaning. The John Roberts Company initiated several changes which reduced the amount
of solvent used and eliminated TCA from the blanket wash. The formulation of the solvent was changed to
eliminate TCA. The wipers are now centrifuged to extract cleaning solvent. The reclaimed solvent is used in
parts washers to clean ink trays and roller chains. Spent solvent is sent out for fuel blending. The explosion-proof
centrifuge cost $15,000. In its first year of operation, John Roberts Company saved $34,000 in solvent
purchases. The laundry's problems in cleaning the solvent soaked wipers have been eliminated. Fugitive emissions
have been reduced in the printery because the new formulation is less volatile.
Jeff Adrian, John Roberts Co., 9687 East River Rd., Minneapolis, MN, 55433, Design for the Environment, Case
Study 1, US EPA
Martin Marietta Astronautics has replaced 1,1,1-trichloroethane (TCA) and methyl ethyl ketone (MEK) with a
terpene cleaner for handwiping operations. The terpene cleaner was decided upon after 16 months of extensive
testing of citrus and alkaline-based compounds. Workers prefer the citrus-based cleaner because it is more
efficient. The terpene cleaner leaves less residue resulting in higher coating bond strength. Martin Marietta
estimates the change has reduced toxic emissions by thousands of pounds per year. Research costs were $350,000 to find a suitable replacement for MEK and TCA. Estimated savings are $250,000 per year.
Dykema, Kevin J., and George R. Larsen. 1993. Shifting the Environmental Paradigm at Martin Marietta
Astronautics. Pollution Prevention Review, Spring:202-204.
Since 1988, Allied-Signal Aerospace in Kansas City, Missouri has used a volatile aqueous cleaner for wiping work
surfaces of laminar flow work stations, finger cots, latex gloves, and fixtures to remove light soils and
particulates. The volatile aqueous cleaner consists of 12.5% isopropyl alcohol, 0.82% surfactant, and the
remainder is deionized water. The solvent removes both organic and inorganic soils. The previous solvent,
CFC-113, was consumed at the rate of 2000 lb/month and has been completely eliminated for wiping. The
volatile aqueous cleaner is also used in ultrasonic baths to clean complicated machined assemblies. Allied-Signal
Aerospace reports better cleaning and lower cost, about $1.00/gallon.
Hand, Tom and Bohnert, George/Allied-Signal Aerospace, Case Study #3: Development and Use of a Volatile
Aqueous Cleaner, EPA/ICOLP Eliminating CFC-113 and Methyl Chloroform in Aircraft Maintenance
Procedures, EPA-430-B-93-006, October 1993, pp. 161-162.
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