Method of removing bitumen from tar sand utilizing ultrasonic energy and stirring

摘要

A method of removing bitumen from tar sand for subsequent recovery of the bitumen. The method comprises contacting tar sand with an excess of solvent in which the bitumen is soluble, said contacting being performed within a vessel wherein simultaneously the solvent is being stirred and ultrasonic energy is being applied, the ultrasonic energy being of an intensity sufficient to break apart any connections between sand granules and to remove bitumen from the sand granules to thereby permit the bitumen so removed to go into solution in the solvent for subsequent removal of the solvent-plus-bitumen and recovery of the bitumen therefrom. Stirring within the vessel reduces residence time required for removal of the bitumen from the tar sand by constantly changing that portion of the solvent directly in contact with the surface of the tar sand to thereby cause even loading of all of the solvent with the bitumen. The vessel utilized can be a column through which the tar sand falls as ultrasonic energy is applied and stirring occurs therein.