ABSTRACT
Halogenated solvents such as trichlorethylene (TCE), freon, and methylene chloride, are routinely used in a wide variety of degreasing and cleaning operations.’ These highly volatile solvents remove unwanted oils, greases, metal residues, and other organic films leaving a clean dry surface. Federal regulations promulgated over the past ten years have classified many of these substances as hazardous (Resource Conservation and Recovery Act —RCRA) or toxic (Toxic Substance Control Act —TSCA). Halogenated solvents release vapors 2 that accumulate in the work place and produce acute and sometimes chronic health effects resulting from continuous exposure through inhalation. 3 Spent halogenated solvents released from process washwater or in concentrate can adversely impact industrial wastewater treatment plants, industrial pretreatment programs and may pose a threat to ground water. 4 Various strategies for minimizing the use and disposal costs of halogenated solvents have been suggested, including: use of solvent substitutes; recycling through filtration and distillation; or sophisticated vapor containment and recovery systems.’
