The cost for removing chemicals farm the soil with present technology is enormous. In some cases, populations must be relocated and many acre-feet of soil must be excavated and treated or stored in "safe" storage facilities. Improved technology is needed to reduce clean-LIP costs. Ultimate removal of toxic chemicals should involve their chemical alteration to non-toxic species. High temperature oxidation (thermal destruction) is a known method for accomplishing this objective. However, in the case of toxics adsorbed on soil in low concentrations, large amounts of soil must be heated to high oxidation temperatures (1500 - 2000øF) in order to insure the destruction of the toxic chemicals. This requires large amounts of auxiliary fuel to increase the enthalpy of the soil mass, unless energy efficient thermal destruction processes are developed. This proposal presents the concept of a staged fluid bed contactor which is designed to minimize fuel requirements through effective heat recovery while simultaneously providing the high temperatures and residence times needed to insure toxic burnout. It is anticipated that the successful completion of this research will lead to the commercialization of a Process Unit for the thermal decontamination of soils at a cost in the range of $1 per ton. The unit can be designed as a self-contained system and transported to sites containing soils contaminated with toxic chemicals. The system offers a large @ t savings over current technologies available for soil decontamination.
