Low temperature bitumen recovery process

Abstract

A low temperature process for separating bitumen from tarsands comprises slurrying tarsands in water at a temperature in the range of above about freezing to 35.degree. C., preferably in the range of 2.degree. to 15.degree. C., mixing said aqueous slurry with a conditioning agent for a time sufficient to release bitumen from tarsands and to uniformly disperse the conditioning agent on the bitumen, and subjecting the resulting slurry to froth flotation for recovery of a bitumen product and production of sand tails. The process can be integrated with dredge or dry mining of the tarsands wherein the tarsands are normally sheared by a rotary cutter or bucket wheel and slurried with water by a slurry pump under attrition mixing conditions, with waterjet mining of tarsands in open pits wherein the resulting slurry can be collected by mechanical equipment, slurry pumps or the like gathering equipment, the resulting slurry fed to a pipeline and the conditioning agent added to the slurry pipeline for mixing with the slurry, or with borehole mining of tarsands wherein high pressure jets of water or water with conditioning agent disintegrates the tarsands in situ for initial slurrying of the tarsands. The conditioning agent preferably is a flotation agent having the characteristics of kerosene, diesel or kerosene/diesel together with a frother having the characteristics of methyl-isobutyl-carbinol and can be mixed with the aqueous slurry by attrition scrubbing or by flotation cell mixing. The slurry may contain up to 70% by weight tarsands and normally is adjusted by dilution to 15 to 30% by weight tarsands in water prior to froth flotation in one or two stages.