Methods for obtaining bitumen from bituminous materials
View Patent ↗Methods for extracting bitumen from bituminous material through the use of a polar solvent. The method may include a primary leaching or extraction process that separates most of the bitumen from a material comprising bitumen and produces first solvent-wet tailings. A polar solvent is added to the first solvent-wet tailings in order to remove the first solvent (plus any entrained bitumen) from the tailings. A mixture of polar solvent and first solvent produced by the addition of the polar solvent to the first solvent-wet tailings may be phase separated by maintaining the polar solvent-first solvent mixture for a period of time. Alternatively, the polar solvent and first solvent may leave the tailings in a phase separated state. Phase separation may occur due to the presence of water in the polar solvent-first solvent mixture. Water may also be added to the mixture of solvents to serve as an antisolvent and initiate phase separation. The separated solvents may then be recovered and reused in the method.
1. A method comprising:
mixing a material comprising bitumen with a first quantity of first solvent to form a first mixture, wherein the first mixture comprises a bitumen-enriched solvent phase;
separating bitumen-enriched solvent phase from the first mixture to produce first solvent-wet tailings, wherein the first solvent-wet tailings comprise a first solvent component;
adding a polar solvent to the first solvent-wet tailings to separate first solvent component from the first solvent-wet tailings and produce polar solvent-wet tailings, wherein the first solvent component is separated from the first solvent-wet tailings as part of a polar solvent-first solvent mixture, wherein the polar solvent comprises an oxygenated hydrocarbon; and
maintaining the polar solvent-first solvent mixture for a period of time to allow the polar solvent-first mixture to phase separate into a polar solvent phase and a first solvent phase.
2. The method of claim 1 , further comprising:
separating the polar solvent phase from the first solvent phase.
3. The method as recited in claim 2 , wherein the polar solvent phase is added to further first solvent-wet tailings.
4. The method as recited in claim 1 , wherein separating bitumen-enriched solvent phase from the first mixture comprises:
filtering or settling the first mixture to separate a first quantity of the bitumen-enriched solvent phase from the first mixture; and
adding a second quantity of first solvent to the first mixture to separate a second quantity of the bitumen-enriched solvent phase from the first mixture.
5. The method as recited in claim 4 , wherein adding a second quantity of first solvent to the first mixture comprises washing the first mixture with the second quantity of first solvent in a countercurrent process.
6. The method as recited in claim 4 , wherein adding the second quantity of first solvent to the first mixture comprises adding the second quantity of first solvent to the first mixture loaded in a plate and frame-type filter press.
7. The method as recited in claim 6 , wherein adding the second quantity of first solvent to the first mixture further comprises adding a pressurized gas over the first mixture loaded in the plate and frame-type filter press.
8. The method as recited in claim 1 , wherein adding the polar solvent to the first solvent-wet tailings comprises washing the first solvent-wet tailings with the polar solvent in a countercurrent process.
9. The method as recited in claim 1 , wherein the first solvent comprises a light aromatic solvent.
10. The method as recited in claim 1 , wherein adding the polar solvent to the first solvent-wet tailings comprises adding the polar solvent to the first solvent-wet tailings loaded in a plate and frame-type filter press.
11. The method as recited in claim 10 , wherein adding the polar solvent to the first solvent-wet tailings further comprises adding a pressurized gas over the first solvent-wet tailings loaded in the plate and frame-type filter press.
12. The method as recited in claim 1 , wherein the material comprising bitumen comprises tar sands.
13. The method as recited in claim 1 , wherein separating bitumen-enriched solvent phase from the first mixture comprises:
loading the first mixture in a vertical column having a top end and a bottom end;
adding a second quantity of first solvent into the first mixture loaded in the vertical column at the top end of the vertical column; and
collecting a first quantity of the bitumen-enriched solvent phase at the bottom end of the vertical column.
14. The method as recited in claim 13 , further comprising:
adding a third quantity of first solvent into the first mixture loaded in the vertical column at the top end of the vertical column; and
collecting a second quantity of the bitumen-enriched solvent phase at the bottom end of the vertical column.
15. The method as recited in claim 13 , wherein the first solvent-wet tailings are discharged from the vertical column prior to adding the polar solvent to the first solvent-wet tailings.
16. The method as recited in claim 15 , further comprising:
injecting a heated gas into the polar solvent-wet tailings to separate polar solvent from the polar solvent-wet tailings loaded in the vertical column.
17. The method as recited in claim 13 , wherein adding the polar solvent to the first solvent-wet tailings comprises:
adding a first quantity of the polar solvent into the first solvent-wet tailings loaded in the vertical column; and
collecting a first quantity of the polar solvent-first solvent mixture at the bottom end of the vertical column.
18. The method as recited in claim 17 , further comprising:
adding a second quantity of the polar solvent into the first solvent-wet tailings loaded in the vertical column; and
collecting a second quantity of the polar solvent-first solvent mixture at the bottom end of the vertical column.
19. The method as recited in claim 17 , further comprising adding a pressurized gas over the first solvent-wet tailings loaded in the vertical column prior to or after adding the first quantity of the polar solvent into the first solvent-wet tailings loaded in the vertical column.
20. The method as recited in claim 1 , wherein the bitumen-enriched solvent phase comprises a bitumen component and further comprising upgrading the bitumen component.
21. The method as recited in claim 1 , wherein the oxygenated hydrocarbon comprises ethanol, methanol, butanol, isopropyl alcohol or tert-butyl alcohol.
22. The method as recited in claim 1 , wherein the oxygenated hydrocarbon is an alcohol, ketone, or ether.
23. A method comprising:
mixing a material comprising bitumen with a first quantity of first solvent to form a first mixture, wherein the first mixture comprises a bitumen-enriched solvent phase;
separating bitumen-enriched solvent phase from the first mixture to produce first solvent-wet tailings, wherein the first solvent-wet tailings comprise a first solvent component;
adding a polar solvent to the first solvent-wet tailings to separate first solvent component from the first solvent-wet tailings and produce polar solvent-wet tailings, wherein the first solvent component is separated from the first solvent-wet tailings as part of a polar solvent-first solvent mixture;
maintaining the polar solvent-first solvent mixture for a period of time to allow the polar solvent-first mixture to phase separate into a polar solvent phase and a first solvent phase; and
adding a first quantity of water to the polar solvent-first solvent mixture.
24. A method comprising:
mixing a material comprising bitumen with a first quantity of first solvent to form a first mixture, wherein the first mixture comprises a bitumen-enriched solvent phase;
separating bitumen-enriched solvent phase from the first mixture to produce first solvent-wet tailings, wherein the first solvent-wet tailings comprise a first solvent component;
adding a polar solvent to the first solvent-wet tailings to separate first solvent component from the first solvent-wet tailings and produce polar solvent-wet tailings, wherein the first solvent component is separated from the first solvent-wet tailings as part of a polar solvent-first solvent mixture; and
maintaining the polar solvent-first solvent mixture for a period of time to allow the polar solvent-first mixture to phase separate into a polar solvent phase and a first solvent phase;
wherein separating polar solvent from the polar solvent-wet tailings comprises heating the polar solvent-wet tailings to a temperature above the boiling point temperature of the polar solvent.
25. The method as recited in claim 24 , wherein the light aromatic solvent comprises kerosene, diesel, gas oil, naphtha, benzene, toluene, an aromatic alcohol, derivatives thereof, or a combination thereof.
26. A method comprising:
mixing a material comprising bitumen with a first quantity of first solvent;
separating a bitumen-enriched solvent phase from a first result of mixing the material comprising bitumen with the first quantity of first solvent;
adding a polar solvent to a second result of separating bitumen-enriched solvent phase from the first result;
maintaining a third result of adding a polar solvent to the second result for a period of time; and
adding a first quantity of water to the third result.
27. The method as recited in claim 26 , wherein separating the bitumen-enriched solvent phase from the first result of mixing the material comprising bitumen with the first quantity of first solvent comprises adding first solvent to the first result.
28. The method as recited in claim 27 , wherein the first solvent comprises a light aromatic solvent.
29. The method as recited in claim 28 , wherein the light aromatic solvent comprises kerosene, diesel, gas oil, naphtha, benzene, toluene, an aromatic alcohol, derivatives thereof, or a combination thereof.
30. The method as recited in claim 26 , wherein the polar solvent comprises methanol, ethanol, propanol or butanol.
31. A method comprising:
i) mixing a material comprising bitumen with a first quantity of first solvent to form a first mixture, wherein the first mixture comprises bitumen-enriched solvent phase;
ii) adding a pressurized gas over the first mixture to separate a first quantity of bitumen-enriched solvent phase from the first mixture;
iii) adding a second quantity of bitumen-enriched solvent phase to the first mixture to separate a second quantity of bitumen-enriched solvent phase from the first mixture and produce first solvent-wet tailings, wherein the first solvent-wet tailings comprise a first solvent component;
iv) adding a first quantity of polar solvent to the first solvent-wet tailings to separate a first quantity of first solvent component from the first solvent-wet tailings, wherein the first quantity of first solvent component is separated from the first solvent-wet tailings as part of a polar solvent-first solvent mixture, wherein the polar solvent comprises an oxygenated hydrocarbon;
v) adding a pressurized gas over the first solvent-wet tailings; and
vi) maintaining the polar solvent-first solvent mixture for a period of time to allow the polar solvent-first mixture to phase separate into a polar solvent phase and a first solvent phase.
32. The method as recited in claim 31 , wherein iii) is repeated one or more times.
33. The method as recited in claim 31 , wherein iv) and v) are repeated one or more times.
34. A method comprising:
mixing a material comprising bitumen with a first quantity of first solvent to form a first mixture, wherein the first mixture comprises a bitumen-enriched solvent phase;
separating bitumen-enriched solvent phase from the first mixture to produce first solvent-wet tailings, wherein the first solvent-wet tailings comprise a first solvent component; and
adding a polar solvent to the first solvent-wet tailings to separate first solvent component from the first solvent-wet tailings and produce polar solvent-wet tailings, wherein the first solvent component is separated from the first solvent-wet tailings as a separated phase of a phase separated polar solvent-first solvent mixture, wherein the polar solvent comprises an oxygenated hydrocarbon.