Abstract: A sludge, or other material containing solid matter and bound and unbound water, is dewatered by admixing the sludge with an amine having an inverse critical solution point with water, always maintaining the temperature of the resulting slurry below the inverse critical solution temperature, and thereafter separating the solid matter from the resulting single phase liquid.The single phase liquid is then heated to a temperature above the inverse critical solution point to form an amine phase and a water phase, after which the water phase is separated from the amine phase. The liquid-solid separation rate is significantly increased by preventing the slurry temperature from rising above the inverse critical solution temperature during mixing and separation.

Abstract: A method for processing an oil-water emulsion to remove oily material therefrom comprising forming a mixture of the oil-water emulsion with liquid amine, in which oils of the emulsion are soluble and having an inverse critical solution point with water, at a temperature below the phase separation temperature of the amine and water so as to form a single liquid phase of amine, oil and water, separating said single liquid phase from any solids which may be contained in the emulsion, raising the temperature of the resulting single liquid phase above the critical solution temperature to effect liquid phase separation whereby an amine phase containing substantially all of the oily material of the emulsion and a water phase containing substantially no oily material are formed, and then separating the two liquid phases. The amine phase is readily processed to recover oily matter therefrom and may be recycled for the processing of additional oil emulsion.