Abstract

A crude oil product is extracted from a tar sand by first crushing the tar sand as mined and then fine grinding the crushed material in a grinding mill in the presence of a cleansing liquid, such as an aqueous solution of a caustic. The resulting slurry is passed into suitable extractor-classifier equipment, such as that shown in U.S. Pat. No. 3,814,336, in which a body of cleansing liquid is maintained. Agitation of the slurry in such maintained body of cleansing liquid substantially completes removal of the bituminous matter from the sand, and the resulting crude oil and cleansing liquid phase is discharged separately from the sand solid phase. The liquid phase is treated for the removal of residual sand particles and for the separation of residual cleansing liquid from the crude oil. The cleansing liquid so recovered is recycled and the crude oil is passed to further processing or for use as such.