RECOVERY OF HYDROCARBONS USING ELECTRICAL STIMULATION

• US 20070102152A1
• Filed: 09/20/2006
• Published: 05/10/2007
• Est. Priority Date: 09/20/2005
• Status: Abandoned Application

• Current Assignee: Alphonsus Forgeron
• Original Assignee: Alphonsus Forgeron
• Inventors: Forgeron, Alphonsus
• Application Number:
  US11/533,629
• Publication Number:
  US 20070102152A1
• Time in Patent Office: Days
• US Class Current: 166/249
• CPC Class Codes: E21B 43/2401 by means of electricity

Abstract

A method of recovering hydrocarbon such as heavy oil or bitumen from an underground oil-rich reservoir formation such as oil sand or oil shale is provided. One or more substantially vertical wells are drilled into the formation so that the bottom portion of each well extends into the formation and, preferably, below the bottom of the formation. The bottom portion of each well may be enlarged relative to the rest of the well. The bottom portion of the well is substantially filled with conductive liquid, sealed at the surface and high voltage power of up to 72,000 Volts or more is applied via an electrical conductor having an electrode submerged in the conductive liquid. The resulting current flow increases the formation temperature, causing the heavy oil or bitumen to flow from the formation into the bottom portion where it can be removed from the well.

Claims

1. A method for recovering hydrocarbons such as heavy oil or bitumen from an underground oil-rich reservoir formation, comprising:

(a) providing one or more substantially vertical wells, each well having a bottom portion extending into the oil-rich reservoir formation and each well spaced apart from one another;

(b) adding to each well a conductive liquid to substantially fill the bottom portion of each well;

(c) inserting an electrical conductor comprising an electrode into each well so that the electrode is at least partially submerged in the conductive liquid;

(d) applying electrical power to the electrical conductor at a voltage sufficient to heat the conductive liquid and the oil-rich reservoir formation to a temperature sufficient to heat the heavy oil or bitumen in the oil-rich reservoir formation; and

(e) substantially sealing the top of each well to maintain a sufficiently high pressure in each well to prevent evaporation once saturation temperature is reached and to force the heated heavy oil or bitumen to flow into the bottom portion of the well and through the well to the surface of the well.

2. The method as set forth in claim 1, whereby the bottom portion of each well is enlarged relative to the rest of the well.

3. The method as set forth in claim 1, whereby the voltage ranges from between about 13,000 Volts to about 72,000 Volts, or higher.

4. The method as set forth in claim 1, wherein the oil-rich reservoir formation is heated to a temperature of between about 100°

C. to about 300°

C., or higher.

5. The method as set forth in claim 1, wherein the pressure in each well is between about 0.1 MPa to about 6.9 MPa or higher.

6. The method as set forth in claim 1, whereby the saturation temperature is about 250°

C. to about 350°

C.

7. The method as set forth in claim 1 further comprising adding a wetting agent to the conductive liquid.

8. The method as set forth in claim 1, whereby the conductive liquid comprises an electrolyte selected from the group consisting of sulfates, nitrates, acetates, oxalates, bitterns, bromides, and any combination of sulfates, nitrates, acetates, oxalates, bitterns and bromides.

9. The method as set forth in claim 1, the heated heavy oil or bitumen further comprising brackish water, silt and sand, whereby the heated heavy oil or bitumen rises to the top of the conductive liquid and is separated from the brackish water, silt and sand.

10. A method for recovering hydrocarbons such as heavy oil or bitumen from an underground oil-rich reservoir formation, comprising:

(a) providing one or more substantially vertical wells, each well having a bottom portion extending into the oil-rich reservoir formation and each well being lined with a casing;

(b) inserting a production tubing into each well, said production tubing extending at least partially into the bottom portion of said well;

(c) adding to each well a conductive liquid to substantially fill the bottom portion of each well;

(d) inserting through the production tubing an electrical conductor comprising an electrode so that the electrode is at least partially submerged in the conductive liquid;

(e) applying electrical power to the electrical conductor at a voltage sufficient to heat the conductive liquid and the oil-rich reservoir formation to a temperature sufficient to heat the heavy oil or bitumen in the oil-rich reservoir formation; and

(f) substantially sealing the top of each well to maintain a sufficiently high pressure in each well to prevent evaporation once saturation temperature is reached and to force the heated heavy oil or bitumen to flow into the bottom portion of the well and through the production tubing to the surface of the well.

11. The method as set forth in claim 10, whereby the production tubing is moveable so that it can be raised or lowered within the well.

12. The method as set forth in claim 10, whereby each well is sealed by means of a surface arrangement comprising a valve, said valve having an open and a closed position such that when the valve is in the open position the heavy oil or bitumen can flow through the production tubing and be removed at surface.

13. The method as set forth in claim 10, whereby the electrical conductor further comprises an insulation jacket suitable for the operating voltage and temperature.

14. The method as set forth in claim 10, whereby the bottom portion of each well is enlarged relative to the rest of the well.

15. The method as set forth in claim 10, whereby the voltage ranges from between about 13,000 Volts to about 72,000 Volts, or higher.

16. The method as set forth in claim 10, wherein the oil-rich reservoir formation is heated to a temperature of between about 100°

C. to about 300°

C., or higher.

17. The method as set forth in claim 10, wherein the pressure in each well is between about 0.1 MPa to about 6.9 MPa or higher.

18. The method as set forth in claim 10, whereby the saturation temperature is about 250°

C. to about 350°

C.

19. The method as set forth in claim 10 further comprising adding a wetting agent to the conductive liquid.

20. The method as set forth in claim 10, whereby the conductive liquid comprises an electrolyte selected from the group consisting of sulfates, nitrates, acetates, oxalates, bitterns, bromides, and any combination of sulfates, nitrates, acetates, oxalates, bitterns and bromides.

21. The method as set forth in claim 10 further comprising:

(g) separately removing any gas from the formation that has accumulated in the bottom portion of the well.

22. The method as set forth in claim 10, the heated heavy oil or bitumen further comprising brackish water, silt and sand, whereby the heated heavy oil or bitumen rises to the top of the conductive liquid and is separated from the brackish water, silt and sand.

23. The method as set forth in claim 10, whereby the underground oil-rich reservoir formation is oil sand or oil shale.