Apparatus for extraction of hydrocarbon fuels or contaminants using electrical energy and critical fluids

• US 20070137852A1
• Filed: 12/20/2005
• Published: 06/21/2007
• Est. Priority Date: 12/20/2005
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Considine, Brian, Markiewicz, John, Cogliandro, John, Hannon, John, Moses, John, Cogliandro, Maureen
• Granted Patent: US 8,096,349 B2
• Time in Patent Office: Days
• US Class Current: 166/60
• CPC Class Codes: E21B 43/2401 by means of electricity

Abstract

The extraction of hydrocarbon fuel products such as kerogen oil and gas from a body of fixed fossil fuels such as oil shale is accomplished by applying a combination of electrical energy and critical fluids with reactants and/or catalysts down a borehole to initiate a reaction of reactants in the critical fluids with kerogen in the oil shale thereby raising the temperatures to cause kerogen oil and gas products to be extracted as a vapor, liquid or dissolved in the critical fluids. The hydrocarbon fuel products of kerogen oil or shale oil and hydrocarbon gas are removed to the ground surface by a product return line. An RF generator provides electromagnetic energy, and the critical fluids include a combination of carbon dioxide (CO₂), with reactants of nitrous oxide (N₂O) or oxygen (O₂).

Claims

1. A system for producing hydrocarbon fuels from a body of fixed fossil fuels beneath an overburden comprising:

means for transmitting electrical energy down a borehole to heat the body of fixed fossil fuels;

means for providing a critical fluid down the borehole for diffusion into the body of fixed fossil fuels at a predetermined pressure; and

means included with the critical fluid for initializing a reaction with the body of fixed fossil fuels to cause the hydrocarbon fuels to be released.

2. The system as recited in claim 1 wherein the system comprises means for removing the hydrocarbon fuels from the borehole to a ground surface above the overburden.

3. The system as recited in claim 2 wherein the system comprises means at the ground surface for separating the hydrocarbon fuel, gases, critical fluids, or contaminants.

4. The system as recited in claim 1 wherein the means for transmitting electrical energy down a borehole comprises an RF generator coupled to a transmission line for transferring electrical energy to a RF Applicator.

5. The system as recited in claim 1 wherein the means for providing critical fluids comprises means for providing carbon dioxide (CO₂).

6. The system as recited in claim 1 wherein the means for initiating a reaction with the body of fixed fossil fuels comprises a reactant including nitrous oxide (N₂O) or Oxygen (O₂).

7. The system as recited in claim 1 wherein the means for initiating a reaction with the body of fixed fossil fuels comprises a catalyst including one of nano-sized iron oxide (Fe₂O₃), silica aerogel, and nano-sized alumina (AL₂O₃) aerogel.

8. The system as recited in claim 1 wherein the system comprises means, added to the critical fluid, for modifying the polarity and solvent characteristics of the critical fluid.

9. The system as recited in claim 1 wherein the system comprises means for mixing critical fluids, reactants, catalysts or modifiers prior to entering the borehole.

10. The system as recited in claim 1 wherein the system comprises a wellhead positioned on top of the borehole for receiving the critical fluid and the electrical energy and transferring the critical fluid and the electrical energy down the borehole.

11. The system as recited in claim 10 wherein the wellhead comprises means for decoupling RF energy from thermocouple wires extending down the borehole.

12. The system as recited in claim 11 wherein the RF energy decoupling means comprises an RF choke connected to a filter capacitor for each thermocouple line.

13. The system as recited in claim 11 wherein the RF energy decoupling means comprises a hollow RF choke, the RF choke being formed by the thermocouple wires which are insulated and rotated to form a coil, each end of the thermocouple wires being connected to a filter capacitor.

14. The system as recited in claim 10 wherein the wellhead comprises a grounding screen positioned adjacent to an outer surface of the wellhead forming a ground plane to eliminate electromagnetic radiation eminating from around the wellhead for operator safety and performance.

15. The system as recited in claim 10 wherein the wellhead comprises a plurality of ground wires extending radially a distance of approximately one wavelength of the electrical energy frequency and spaced apart at predetermined intervals of approximately 15 degrees.

16. The system as recited in claim 10 wherein the wellhead comprises a grounding screen positioned adjacent to an outer surface of the wellhead forming a ground plane, and a plurality of ground wires extending radially from the perimeter of the grounding screen at a distance of approximately one wavelength of the electrical energy frequency and spaced apart at predetermined intervals.

17. The system as recited in claim 1 wherein the system comprises an auxiliary well spaced apart from the borehole and extending down to the body of fixed fossil fuels for extracting the released hydrocarbon fuels.

18. The system as recited in claim 17 wherein the auxiliary well comprises:

an auxiliary wellhead;

a well pipe extending downward from the wellhead;

a pump coupled to the auxiliary wellhead for bringing fuel products up to a ground surface above the overburden; and

a gas/liquid separator coupled to the auxiliary wellhead.

19. A system for producing hydrocarbon fuels from a body of fixed fossil fuels beneath an overburden comprising a plurality of boreholes each of the boreholes comprises:

means for transmitting electrical energy down each of the boreholes to heat the body of fixed fossil fuels;

means for providing critical fluids down each of the boreholes for diffusion into the body of fixed fossil fuels at a predetermined pressure; and

means included with the critical fluids for initializing a reaction with the body of fixed fossil fuels to cause the hydrocarbon fuels to be released; and

means for controlling the electrical energy and the critical fluids to each of the boreholes.

20. The system as recited in claim 19 wherein the system comprises means for removing the hydrocarbon fuels from each of the boreholes to a ground surface above the overburden.

21. The system as recited in claim 20 wherein the system comprises means at the ground surface for separating the hydrocarbon fuel, gases, critical fluids, or contaminants.

22. The system as recited in claim 19 wherein the means for transmitting electrical energy down each of the boreholes comprises a central RF generator coupled to transmission lines for transferring electrical energy to a RF Applicator in each of the boreholes.

23. The system as recited in claim 22 wherein the system comprises means for impedance matching outputs of the central RF generator to each of the RF applicators in each of the boreholes.

24. The system as recited in claim 22 wherein the means for controlling the electrical energy to each of the boreholes comprises means for shifting sequentially RF power from the central RF generator to the RF applicator in each of the boreholes.

25. The system as recited in claim 19 wherein the means for controlling the critical fluids to each of the boreholes generates control signals to control the critical fluids injected into each of the boreholes.

26. The system as recited in claim 19 wherein the means for providing the critical fluids comprises means for providing carbon dioxide (CO₂).

27. The system as recited in claim 19 wherein the means included with the critical fluids for initiating a reaction with the body of fixed fossil fuels comprises a reactant including nitrous oxide (N₂O) or oxygen (O₂).

28. The system as recited in claim 19 wherein the means included with the critical fluids for initiating a reaction with the body of fixed fossil fuels comprises a catalyst including one of nano-sized iron oxide (Fe₂O₃), silica aerogel, and nano-sized alumina (AL₂O₃) aerogel.

29. The system as recited in claim 19 wherein the system comprises means, added to the critical fluid, for modifying the polarity and solvent characteristics of the critical fluid.

30. The system as recited in claim 19 wherein the system comprises means in each of the boreholes for mixing critical fluids, reactants, catalysts or modifiers prior to entering the borehole.

31. The system as recited in claim 19 wherein the system comprises a wellhead positioned on top of each of the boreholes for receiving the critical fluids and the electrical energy and transferring the critical fluids and the electrical energy down the borehole.

32. The system as recited in claim 28 wherein each of the wellheads comprises means for decoupling RF energy from thermocouple wires extending down the borehole.

33. The system as recited in claim 32 wherein the RF energy decoupling means comprises an RF choke connected to a filter capacitor for each thermocouple line.

34. The system as recited in claim 32 wherein the RF energy decoupling means comprises a hollow RF choke, the RF choke being formed by the thermocouple wires which are insulated and rotated to form a coil, each end of the thermocouple wires being connected to a filter capacitor.

35. The system as recited in claim 31 wherein each of the wellheads comprises a grounding screen positioned adjacent to an outer surface of each of the wellheads forming a ground plane to eliminate electromagnetic radiation eminating from around the wellhead for operator safety and performance.

36. The system as recited in claim 31 wherein each of the wellheads comprises a plurality of ground wires extending radially a distance of approximately one wavelength of the the electrical energy frequency and spaced apart at predetermined intervals of approximately 15 degrees.

37. The system as recited in claim 31 wherein each of the wellheads comprises a grounding screen positioned adjacent to an outer surface of the wellhead forming a ground plane, and a plurality of ground wires extending radially from the perimeter of the grounding screen at a distance of approximately one wavelength of the electrical energy frequency and spaced apart at predetermined intervals.

38. The system as recited in claim 19 wherein the system comprises an auxiliary well spaced apart from the plurality of boreholes and extending down to the body of fixed fossil fuels for extracting the released hydrocarbon fuels.

39. The system as recited in claim 38 wherein the auxiliary well comprises:

an auxiliary wellhead;

a well pipe extending downward from the wellhead;

a pump coupled to the auxiliary wellhead for bringing fuel products up to a ground surface above the overburden; and

a gas/liquid separator coupled to the auxiliary wellhead.