| 摘要 |
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 +E,fra 1/8+EE inch) with atmospheric pressure steam in a specially designed slurry heater(s), contacting the hot (95 DEG -99 DEG 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 DEG C., separating the -+E,fra 1/8+EE inch solids from the slurry exiting the tumbler and recycling a portion of the -+E,fra 1/8+EE inch solids in slurry back to slurry heater(s). In order to reach the required temperature in the tumbler, the -+E,fra 1/8+EE 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. Under such conditions, the fine (-+E,fra 1/8+EE inch) components of the soil are processed under more rigorous conditions (steam, high temperature, residence time, agitation) compared to large (+E,fra 1/8+EE -5.0 inch) mineral components of the soil. This results in further improvement of thermal efficiency of the process.
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