The development of a simple, efficient, nonchemistry-specific effluent treatment system would be of tremendous benefit to the semiconductor process industry. The scrubber proposed in this SBIR project would remove reaction by-products from the process exhaust by condensation onto cryogenically cooled surfaces. Once condensed as liquid or solid, the waste would be separated mechanically, nonhazardous material would be released, toxic material would be incinerated, and the ash collected for hazardous waste disposal. A secondary objective of the research is to examine the feasibility of using the (liquid) nitrogen as the working fluid of a heat engine, to extract waste heat as work from the gas stream. The final goal of the research will be a commercial system which will liquefy air, separate out the oxygen from the nitrogen, condense and then incinerate the waste from industrial effluent, condense the waste from the incineration, and use the energy thus collected to liquefy more air. Such a system may well be able to generate excess energy, as well as decrease toxic waste emissions.