Method for extracting bitumen from an oil sand feed stream
View Patent ↗A method for extracting bitumen from an oil sand feed stream comprises at least the steps of: (a) providing an oil sand feed stream; (b) contacting the oil sand feed stream with a liquid comprising an aliphatic hydrocarbon solvent thereby obtaining a solvent-diluted oil sand slurry; (c) filtering the solvent-diluted oil sand slurry, thereby obtaining a first bitumen-enriched filtrate, a second bitumen-depleted filtrate and a bitumen-depleted sand; (d) reusing the second filtrate obtained in step (c) in the contacting of step (b); and (e) removing solvent from the first bitumen-enriched filtrate thereby obtaining a bitumen-enriched stream.
1. A method for extracting bitumen from an oil sand feed stream, the method comprising at least the steps of:
(a) providing an oil sand feed stream;
(b) contacting the oil sand feed stream with a liquid comprising an aliphatic hydrocarbon solvent thereby obtaining a solvent-diluted oil sand slurry;
(c) filtering the solvent-diluted oil sand slurry, thereby obtaining a first bitumen-enriched filtrate, a second bitumen-depleted filtrate and a bitumen-depleted sand;
(d) reusing the second filtrate obtained in step (c) in the contacting of step (b); and
(e) removing solvent from the first bitumen-enriched filtrate thereby obtaining a bitumen-enriched stream.
2. The method according to claim 1 , wherein the solvent in step (b) comprises an aliphatic hydrocarbon having from 3 to 9 carbon atoms per molecule.
3. The method according to claim 1 , wherein the solvent in step (b) comprises a saturated hydrocarbon.
4. The method according to claim 1 , wherein the particles of the solvent-diluted oil sand slurry obtained in step (b) are screened or reduced in size to have a diameter below 5.0 cm.
5. The method according to claim 1 wherein the solvent-diluted oil sand slurry obtained in step (b) has a solvent-to-bitumen (S/B) weight ratio of from 1.2 to 4.0.
6. The method according to claim 1 wherein the solvent-diluted oil sand slurry obtained in step (b) comprises from 32 to 60 vol. % of solids.
7. The method according to claim 1 wherein the first filtrate obtained in step (c) has a S/B weight ratio of from 1.0 to 5.0.
8. The method according to claim 1 wherein the second filtrate obtained in step (c) has a SB weight ratio of above 3.0.
9. The method according to claim 1 wherein the solvent removed from the first filtrate in step (e) is reused in step (c).
10. The method according to claim 9 , wherein at least part of the solvent removed from the first filtrate is removed as vapour.
11. The method according to claim 10 , wherein at least part of the vapour is condensed in step (c).
12. The method according to claim 1 wherein the bitumen-depleted sand stream is dried, thereby obtaining a dried bitumen-depleted sand stream containing less than 500 ppmw.