Steam
Case Studies
FMC Corporation, Naval Systems Division, has eliminated its use of 1,1,1 -trichloroethane in manufacturing
naval weapons handling systems. Alkaline detergents are now used for much of the cleaning. Isopropyl alcohol
replaced TCA in foundry operations. Steam degreasing and semiaqueous cleaners are now used in the plating
operations. Elimination of the TCA resulted in a net savings of $29,000 per year from 1991 levels. Isopropyl
alcohol also replaced CFC-113 in the wave solder cleaning of printed circuit boards, reducing the purchase of
CFC-113 by 5,500 lbs annually, and saving FMC $15,000 in chemical purchases.
Douglas L. Hildre, Environmental Control Manager, FMC Corporation, Naval Systems Division, 4800 East River
Road, Fridley, MN, 55421 MnTAP, 1993 Governor's Awards for Excellence in Pollution Prevention.
Emerson Electric Company in Murphy, NC, is a manufacturer of power tools. Solvent degreasing has been
replaced by alkaline detergent and steam degreasing.
Hunt, Gary, et al, eds., Process Modification and Material Recovery at Power Tool Plant, Case Summaries of
Waste Reduction by Industries in the Southeast, North Carolina Department of Natural Resources and
Community Development, July 1989, p. 43.
The Marine Corps Air Station Naval Aviation Depot, Cherry Point, NC, is responsible for the complete
maintenance/rebuilding of naval aircraft. In 1990 the depot used 8000 gallons of CFC-113 and 15,600 gallons of
1,1,1-trichloroethane. By the end of 1992 CFC-113 usage had been reduced to 500 gallons annually and TCA
usage had been cut to about 4800 gallons annually. The replacements included: soap bubbles for leak checks;
aqueous power washers for electronics, motor, and engine shop use; terpene cleaners for hand wiping; steam
cleaning or wet sodium bicarbonate blasting for soil and carbon removal; and plastic media blasting for paint
removal.
Fennell, Mary Beth and Roberts, James Mark/Naval Aviation Depot, Hazardous Minimization-Saving Time,
Money , and the Environment, proceeding of the Aerospace Symposium, January 1993, Lake Buena Vista,
Florida, pp 39-46.
In the Plating Shop at the Warner Robins Air Logistics Center, Robins AFB, GA, wax masks are used to protect
surfaces during the electroplating process. Once the parts have been chrome plated the wax mask must be
removed. The Plating Shop had been dewaxing and degreasing the plated parts simultaneously in
1,1,1-trichloroethane vapor degreasers. The wax sludge buildup in the vapor degreasers required them to be
serviced weekly. Weekly TCA consumption was 400 gallons. The new plating line includes high pressure steam
cabinets for dewaxing the parts. The beeswax mask is softened by the heat and removed by impingement. Vapor
degreasers are still required for completely degreasing the plated parts. Removal of the wax from the degreasers
allows monthly cleanout. Recycling stills also require less frequent cleaning since the wax has been removed from
the TCA. The Plating Shop accounts for 75% of the entire base's TCA usage. While this is not a perfect solution,
it moves Robins AFB closer to its goal of complete TCA elimination.
Sedgwick, Marti/WR-ALC, Case Study #1: De-Waxing Aircraft Components Using Steam Instead of Solvents,
EPA/ICOLP Eliminating CFC-113 and Methyl Chloroform in Aircraft Maintenance Procedures,
EPA-430-B-93-006, October 1993, pp. 157-158.
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