Process and system for treating contaminated particulate soil compositions

Claim 1

A process for treating particulate soil composition having volatilizable organic material therein, said particulate soil including a substantial portion of fine soil particles passing a size 40 U.S. series sieve, comprising: heating said particulate soil composition in a rotating drum while passing hot gases of combustion comprising a mixture of said hot gases of combustion, volatilized organic material and said fine particles, separating said fine particles from said gaseous composition, directing said gaseous composition to a furnace and combusting said volatilized organic material therein, recovering at least a portion of hot exhaust gases from said furnace, and recovering said fine particles separated from said gaseous composition, and directing said recovered hot exhaust gases and recovered fine particles to a heat exchange apparatus having one or more first channels for directing said fine particles therethrough and one or more second channels in heat exchange communication with said first channels for directing said hot exhaust gases therethrough, heating said fine particles and volatilizing organic material therefrom in said heat exchange apparatus and wherein said fine particles and said hot exhaust gases are indirectly exposed in said heat exchange apparatus whereby contamination of said hot exhaust gases with volatilized organic material is avoided therein, and separating volatilized organic material from said fine particles, and recovering said fine particles.