METHOD AND APPARATUS FOR REMOVING ORGANIC CONTAMINANTS FROM INORGANIC-RICH MINERALS SOLIDS

摘要

Method and apparatus for removing oil and other organic constituents from particulate, inorganic-rich mineral solids. The method and apparatus are particularly suitable for removing oil from oil-contaminated drill cuttings. The solids to be treated are transferred into pressure vessel means wherein they are contacted with an extractant which is normally a gas but is under conditions of pressure and temperature to provide the extractant in a fluidic solvent state for the constituents to be removed, whereby the constituents are transferred to the extractant. The extractant containing the constituents is withdrawn from the pressure vessel and depressurized to render it a nonsolvent for the constituents and to form a two-phase system which can then be separated into extractant for repressurizing and recycling with proper handling of the constituents removed. In the case of removing oil from drill cuttings, the essentially oil-free cuttings can be disposed of in any suitable manner including dumping overboard from an offshore drilling rig.