Patent ID: 6213029
Filing Date: 2001-04-10
Classification: B09B,B09C,C02F

Abstract:
A process for recovering and treating hazardous and non-hazardous components from process streams generated from a continuous system for selectively separating organic and inorganic constituents from contaminated material, said process comprising:(a) heating the contaminated material to a first temperature sufficient to volatilize water and lower boiling point constituents contained in the material, thereby producing a dried solid material and a first gas containing water vapor and volatilized lower boiling point constituents, wherein the contaminated material is heated in a dryer, which comprises an indirect heated hot oil screw dryer having a screw for conveying the material;(b) separating the first gas from the dried solid material;(c) recovering the lower boiling point constituents from the first gas;(d) heating the dried solid material in a desorber to a second temperature sufficient to volatilize higher boiling point constituents contained in the dried material, thereby producing a substantially decontaminated solid material and a second gas containing volatilized higher boiling point constituents;(e) separating the second gas from the substantially decontaminated solid material;(f) recovering the higher boiling point constituents from the second gas;(g) heating oil in a hot oil system and feeding the heated hot oil to the screw of the dryer to indirectly heat the contaminated solid material fed to the dryer;(h) feeding inert gases as sweep gas to at least one of the dryer to assist in heating the contaminated material in step (a) and the desorber to assist in heating the dried material and maintaining an appropriate partial pressure to effectively desorb contaminants in step (d); and(i) withdrawing combustion products from the hot oil system and feeding the withdrawn combustion products to inert gas vaporizers, and utilizing heat from the withdrawn combustion products to vaporize liquid inert gas into inert gas in the inert gas vaporizers.