Method for extracting bitumen from an oil sand stream

摘要

The present invention provides a method for extracting bitumen from an oil sand stream, the method including the steps of: (a) providing an oil sand stream; (b) contacting the oil sand stream with a liquid comprising a solvent thereby obtaining a solvent-diluted oil sand slurry; (c) separating the solvent-diluted oil sand slurry, thereby obtaining a first solids-depleted stream and a first solids-enriched stream; (d) filtering the first solids-enriched stream obtained in step (c), thereby obtaining bitumen-depleted sand and at least a first filtrate; (e) increasing the S/B weight ratio of at least a part of the first filtrate by combining it with a stream having a higher S/B weight ratio thereby obtaining a combined stream; and (f) separating the combined stream, thereby obtaining a second solids-depleted stream and a second solids-enriched stream.

主权项

1. A method for extracting bitumen from an oil sand stream, the method comprising the steps of:
(a) providing an oil sand stream; (b) contacting the oil sand stream with a liquid, the liquid comprising a solvent comprising an aliphatic hydrocarbon having from 3 to 9 carbon atoms per molecule thereby obtaining a solvent-diluted oil sand slurry wherein at least about 90 percent by weight of asphaltenes in the oil sand stream remain dissolved; (c) separating the solvent-diluted oil sand slurry, thereby obtaining a first solids-depleted stream and a first solids-enriched stream; (d) filtering the first solids-enriched stream obtained in step (c), thereby obtaining bitumen-depleted sand and at least a first filtrate, and a second filtrate, and the second filtrate is at least partly reused in the contacting of step (b); (e) increasing a S/B weight ratio of at least a part of the first filtrate by combining it with a stream having a higher S/B weight ratio thereby obtaining a combined stream wherein at least some asphaltenes are caused to precipitate from the combined stream; and (f) separating the combined stream, thereby obtaining a second solids-depleted stream and a second solids-enriched stream wherein the second solids-depleted stream comprises less than two percent by weight of solids.