Abstract: An improved method for heating the aqueous slurries of soils contaminated with tarry/oily organics and volatile compounds. The method includes the steps of heating the slurry (containing inorganic and carbonaceous solids below 1/8 inch) with atmospheric pressure steam in a specially designed slurry heater(s), contacting the hot (95.degree.-99.degree. C.) slurry with the contaminated feed soil (top size 5 inch) in a hydraulic feeder, processing the resultant slurry in a tumbler at temperatures up to 90.degree. C., separating the -1/8 inch solids from the slurry exiting the tumbler and recycling a portion of the -1/8 inch solids in slurry back to slurry heater(s). In order to reach the required temperature in the tumbler, the -1/8 inch slurry has to travel through the tumbler at mass flow rates 1.5-4.0 times higher as compared to those for the soil feed stream.
Abstract: A process is provided for clean-up of soils contaminated with highly viscous coal tar and/or petroleum derived organics. This new invention is based on application of the modified Clean Soil Process integrated with modified thermal desorption technology. This new invention utilizes the unexpected advantages of integration of the Clean Soil Process and conventional thermal desorption which cannot, when applied separately or in sequence (Clean Soil Process followed by Conventional Thermal Desorption), furnish satisfactory clean-up, but when integrated have the capacity to clean the most difficult contaminated soils (including soils contaminated by manufactured gas plants) to about 100 ppm, or less of total soluble organics and less than 3 ppm of PAH's.