Abstract: A method is provided for the treatment of contaminated materials such as impounded sludges and contaminated soils by thermal desorption wherein a solid matrix is subjected to the action of superheated steam in a closed vessel, a gas stream comprising superheated steam is recirculated to the vessel and recirculation of the superheated steam is continued until organic constituents are separated therefrom to predetermined concentrations that are environmentally insignificant and within the limits prescribed by governmental regulations.

Abstract: A method and apparatus are provided for remediating contaminated soil having volatilizable organic pollutants in a heated treatment zone, preferably a rotary drum, in gas/solids contact with superheated steam. Treatment gases from the treatment zone are repressurized and reheated for reuse in the treatment zone. Superheated steam is maintained in a closed loop and is maintained at superheated conditions. Vaporized organic pollutants and superheated steam are removed from the closed loop of superheated steam for cooling and condensation to condense water and condense liquid volatilizable organic pollutants and uncondensed organic pollutant vapors.

Abstract: A novel and improved method is provided for treatment of materials contaminated with environmentally significant amounts of volatile and semi-volatile organic pollutants, the method including the essential steps of fluidization, acidification, and filtration of a contaminated solids material to yield a first treated solids product; recycling of the first treated solids product and admixture of the recycled first treated solids product with additional contaminated solids product; and continuously subjecting a mixture of first treated solids product and contaminated solids product to fluidization, acidification, filtration, recycling, and admixture until a product exhibiting predetermined characteristics is produced.

Abstract: A method and apparatus for treating sludges that have resulted from chemical treatment of sulfuric acid wastes with lime are shown. The sludges are subjected to fluidization, dilution, and acidification to solubilize solids, clarification to concentrate solids for reacidification and produce a supernatant for carbon adsorption to remove organics and color, with regeneration of spent carbon including incineration of solids, and finally incineration of the spent carbon and all other remaining unsolubilized solids.