Recovery of oil from bituminous sands

Claim 1

METHOD OF SEPARATING OIL FROM BITUMINOUS SANDS, SUCH AS ALBERTA TAR SANDS, IN WHICH THE OIL HAS A DENSITY GREATER THAN THAT OF WATER, WHICH COMPRISES: MULLING THE BITUMINOUS SAND WITH A MINOR AMOUNT OF WATER AT A TEMPERATURE ABOVE 50*F. FOR A TIME SUFFICIENT TO BREAK THE OIL FILM FROM AROUND THE SAND PARTICLES BUT INSUFFICIENT TO CAUSE THE OIL TO STICK TO THE SAND; VIGOROUSLY MIXING THE MULLED MATERIAL WITH A LARGE VOLUME OF COLD WATER; FEEDING THE RESULTING MIXTURE AT A TEMPERATURE ABOVE FREEZING BUT BELOW 50*F. INTO A SEPARATING ZONE HAVING A BOTTOM WALL INCLINED AT AN ANGLE OF 28-35* AND SUBJECTED TO VIBRATIONS; FLOWING THE MIXTURE ALONG THE BOTTOM WALL WHILE MAINTAINING A WATER LEVEL IN THE UPPER PART OF THE SEPARATING ZONE, WHEREBY SAND PARTICLES SEPARATE AS A LOWER LAYER, OIL SEPARATES AS AN INTERMEDIATE LAYER AND WATER CONTAINING CLAY OR SILT SEPARATES AS AN UPPER LAYER; AND SEPARATELY REMOVING SAID LAYERS.