RECUPERATIVE THERMAL SCREW CONTAMINATED SOIL CLEANING SYSTEM (CSCS)

IMPROVED TECHNOLOGY IS NEEDED TO PROVIDE RAPID, INEXPENSIVE, ON-SITE TREATMENT AND CLEANUP OF SOILS CONTAMINATED BY PETROLEUM HYDROCARBONS AND SOLVENTS. TREATED SOILS SHOULD BE SUITABLE FOR REPLACEMENT IN THEIR OWN EXCAVATION, AND THE TREATMENT PROCESS SHOULD NOT GENERATE ANY SECONDARY WASTES. IN ADDITION, TREATMENT TECHNOLOGY SHOULD BE SIMPLE, ROBUST, EFFIENENT, RELIABLE, AND CAPABLE OF TREATING AL TYPES OF SOILD HAVING WIDE VARIATION IN CONTAMINANT CONCENTRATION AND MOISTURE CONTENT. A MOBILE CONTAMINATED SOIL CLEANING SYSTEM (CSCS), UTILIZING AN INNOVATIVE HIGH-EFFICIENCY THERMAL SCREW FOR LOW-TEMPERATURE THERMAL DESORPTION, PROMISES TO FULFULL THIS TECHNOLOGY NEED. DESIGN AND DEMONSTRATION OF THE TECHNOLOGY CONCEPT REQUIRE GENERATION OF PARAMETRIC DATA FOR INDIRECT HEAT TRANSFER BETWEEN MOVING BEDS OF MOIST SOLIDS OR SLUDGES. PILOT PLANT FACTORIAL PARAMETRIC TESTS ARE PROPOSED WHICH WILL YIELD OVERALL AND FILM HEAT TRANSFER COEFFICIENTS NECESSARY FOR DESIGN OF A DEMONSTRATION CSCS. HEAT TRANSFER COEFFICIENTS WILL BE DETERMINED AS A FUNCTION OF WALL TEMPERATURE, SOIL TYPE, SHEAR VECTOR MAGNITUDE, AND SOIL MOISTURE CONTENT. HEAT TRANSFER AND PERFORMANCE DATA DERIVED FROM THE PROPOSED RESEARCH ALSO WILL BE GENERALLY APPLICABLE TO THE DESIGN OF THERMAL SCREW SYSTEMS FOR INDUSTRIAL SOLIDS HANDLING, HEAT TREATMENT, AND DRYING.