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Show resulting product can be extruded into drums or fo:rns, creating solid blocks, or it can be placed in-situ. This solidification process has been used an wastes fran several chemical CCJIpanies. UOOer the SITE program, EPA is interested in dem::mstrating the applicability of this process to organic sludges aId , : :" ...... soils contami nated with organic naterials. Vacuum Extraction. Terra Vac, Inc., bas developed a process for in-situ vacuun extraction of volatile contaminants fran soils and gramdwater. Extraction wells are placed in the lmSaturated soil zane above the water table. A vacuun source is applied to the \tell aId volatile organic Carp:tlndS are drawn off. The gas stream is passed through an \ .,,'!, \:.. activated carbon abscn:ption systan to control air emissions. The systEm . . can also be used to PUDP gramdwater to the surface for treatnent by spray .~. .. . .... ,\. ; .', ~',. }. aeration. ,.1 ••• ,'.' ~" c , ~ .. ' ... ' Vacutm extraction sJ:xnlld provide advantages in situations where excavation of contaminated soils is iIrpractical or very costly. It was used to clean up a spill Of carbon tetrachloride fran a ruptured UIX3er~ storage tank. 'nle vacuum extraction rate of carbon tetrachloride reached 250 p:ilndS per day fran an unsaturated soil zone 300 feet deep. After 30 m:mtbs of operation, uore than 70 percent of the spilled voltme was rancNed fran this zone. In other applications, uethylene chloride am gasoline ~ successfully extracted fran contaminated soils. A SITE dem:mstration is being develo{:ed to evaluate this process an soils contaminated with volatile organic ccnpounds, hydrocarlxms, am solvents. Pyroplasma System. The pyroplasma process pyrolyzes wastes using a thennal plasma field. The heart of the systan is a plasma arc torch which prc:xiuces a t:hennal. plasra with tarperatures of rrore than 9000oF. Waste liquids are injected directly into the plasma where the IOOlecules are broken into their atanic states am the atans then recanbine to prc:xiuce llydrogen, carbon IIODOXide, nitrogen, hydrogen chloride, Pll'ticulate carbon, snaJ.I anounts of carlxm diaxide, ethylene, and acetylene. The product gas is scrubbed with caustic soda to neutral ize and rem:lV'e the acid gases and rerrove particulates. The pyroplasma systan is capable of destroying any ~le liquid organic waste. The system has been operated in a series of tests using nethyl ethyl ketone, methanol, ethanol, carbon tetrachloride, and Askarel. The unit is not designed to destroy solids altlx>ugh it can handle up to 40 percent solids if they are ~le and can pa.ss through a 200 mesh screen. Heavy netals pa.ss through the system in the scrubber water. A IId:>ile unit IIOlIlted on a 48-foot trailer is available and can process 2 to 3 gallons per minute. 'lWo SITE projects will use this technology. In one project, the NStI York State DepartIrent of Enviromental Conservation am Pyrolysis Qystems, Inc., will use a mObile plasma arc unit for the destruction of sludges fran Love Canal. A secoIrl project will evaluate a larger unit developed by Westinghouse Plasma Systems. 6 |