Regenerative combustion device

• US 20020141288A1
• Filed: 05/28/2002
• Published: 10/03/2002
• Est. Priority Date: 10/20/2000
• Status: Active Grant

• Current Assignee: Battelle Energy Alliance LLC (Battelle Memorial Institute)
• Original Assignee: Bechtel BWXT Idaho, LLC
• Inventors: West, Phillip B.
• Granted Patent: US 6,705,425 B2
• Time in Patent Office: Days
• US Class Current: 367/145
• CPC Class Codes: E21B 28/00 Vibration generating arrangements for boreholes or wells, e.g. for stimulating production for fishing for or freeing objects E21B31/005; for transmitting measuring-signals E21B47/14; for geophysical measurements G01V1/02
• CPC Class Codes: E21B 43/003 Vibrating earth formations
• CPC Class Codes: E21B 43/26 by forming crevices or fractures
• CPC Class Codes: F02G 3/00 Combustion-product positive-displacement engine plants
• CPC Class Codes: G01V 1/104 using explosive charges G01V1/157 takes precedence
• CPC Class Codes: G01V 1/40 specially adapted for well-logging

Abstract

A regenerative combustion device having a combustion zone, and chemicals contained within the combustion zone, such as water, having a first equilibrium state, and a second combustible state. Means for transforming the chemicals from the first equilibrium state to the second combustible state, such as electrodes, are disposed within the chemicals. An igniter, such as a spark plug or similar device, is disposed within the combustion zone for igniting combustion of the chemicals in the second combustible state. The combustion products are contained within the combustion zone, and the chemicals are selected such that the combustion products naturally chemically revert into the chemicals in the first equilibrium state following combustion. The combustion device may thus be repeatedly reused, requiring only a brief wait after each ignition to allow the regeneration of combustible gasses within the head space.

Claims

1. A regenerative combustion device, comprising:

a combustion zone;

chemicals contained within the combustion zone, having a first equilibrium state, and a second combustible state;

means for transforming the chemicals form the first equilibrium state to the second combustible state; and

an igniter for igniting combustion of the chemicals in the second combustible state, wherein the combustion products are contained within the combustion zone, and the chemicals are selected such that the combustion products reversibly transform into the chemicals in the first equilibrium state following combustion.

2. The regenerative combustion device of claim 1, wherein the combustion zone comprises a chamber within a pressure vessel.

3. The regenerative combustion device of claim 1, wherein the combustion zone comprises a space at least partially bounded by a subterranean surface of a well and by at least one well packer positioned within the well.

4. The regenerative combustion device of claim 1, wherein the combustion zone comprises a space at least partially bounded by subterranean surface of a well and by a gas trap positioned within the well.

5. The regenerative combustion device of claim 1, wherein the chemicals in the first equilibrium state comprise an aqueous solution of water and sodium hydroxide (NaOH), and the chemicals in the second combustible state comprise gaseous hydrogen and gaseous oxygen.

6. The regenerative combustion device of claim 1, wherein the means for transforming the chemicals from the first equilibrium state to the second combustible state comprises a voltage applied across electrodes disposed in contact with an aqueous solution adjacent the combustion zone.

7. The regenerative combustion device of claim 1, wherein the igniter is selected from the group consisting of a spark plug, a hot wire, a plasma discharge device, a piezo-electric element, a catalyst, increased pressure, and shock applied to the gasses in the combustible state.

8. A regenerative seismic sound source for seismological surveys comprising:

a sealed chamber containing a liquid electrolyte and a head space;

a plurality of electrodes disposed in contact with the liquid electrolyte;

an igniter disposed in the head space;

an electrical power source configured to provide electrical power to the electrodes so as to cause the electrolyte to form a combustible mixture within the head space and also to the igniter so as to ignite the combustible mixture within the head space and produce combustion products therefrom, the combustion products being entirely contained within the chamber, the electrolyte being selected such that the combustion products reversibly transform back into liquid electrolyte over time following combustion.

9. The regenerative seismic sound source of claim 8, wherein the liquid electrolyte comprises and aqueous solution of water and sodium hydroxide (NaOH).

10. The regenerative seismic sound source of claim 8, wherein the combustible mixture comprises gaseous hydrogen and gaseous oxygen in the head space.

11. The regenerative seismic sound source of claim 8, wherein the sealed chamber is disposed in a subterranean location.

12. The regenerative seismic sound source of claim 8, wherein the sealed chamber is configured for being towed behind a water-going vessel.

14. The system of claim 13, wherein the chemicals in the first equilibrium state comprise and aqueous solution of water and sodium hydroxide (NaOH).

15. The system of claim 13, wherein the combustion zone comprises a space bounded at least partially by a subterranean surface of the well and by a device selected from the group comprising a well packer and a gas trap.

16. The system of claim 15, further comprising a conduit in communication with the combustion zone to provide pressurized air thereto and create a head space therein.

18. The method according to claim 17, wherein the positioning a regenerative combustion device within the well further comprises positioning within the well a sealed chamber containing a liquid electrolyte, a head space, a plurality of electrodes disposed within the liquid electrolyte, and an igniter disposed in the head space.

19. The method according to claim 17, wherein the positioning a regenerative combustion device within the well further comprises positioning within the well at least one packer, an igniter and a plurality of electrodes disposed below the packer, so as to form a combustion zone below the at least one packer which is bounded at least partially by the packer and a subterranean surface of the well.

20. The method according to claim 19, further comprising pumping compressed air into the combustion zone so as to form a head space therein, disposing the igniter in the head space, and disposing the electrodes at least partly in water located below the packer.

21. The method according to claim 17, further comprising maintaining the regenerative combustion device within the well, providing electrical current to the regenerative combustion device a second time to regenerate the combustible gas within the combustion zone through electrolysis and igniting the regenerated combustible gas within the combustion zone.

22. The method according to claim 20, further comprising repositioning the regenerative combustion device to a second location within the well prior to the providing electrical current a second time.

24. The method according to claim 23, wherein the disposing a liquid electrolyte includes disposing an aqueous solution of water and sodium hydroxide.

25. The method according to claim 23, wherein the creating a combustible mixture includes creating gaseous hydrogen and gaseous oxygen.

26. The method according to claim 23, wherein the creating a combustible mixture includes subjecting the liquid electrolyte to electrolysis.

27. The method according to claim 23, wherein igniting the combustible mixture includes providing heat to the combustible mixture.

28. The method according to claim 23, wherein igniting the combustible mixture includes pressurizing the combustible mixture.

13. A system for conducting seismological surveys comprising:

a subterranean well;

a regenerative seismic sound source comprising;

a combustion zone;

chemicals contained within the combustion zone, having a first equilibrium state, and a second combustible state;

means for transforming the chemicals form the first equilibrium state to the second combustible state; and

an igniter for igniting combustion of the chemicals in the second combustible state;

a positioning device configured to position the regenerative seismic sound source within the well;

an electrical power source coupled to the means for transforming the chemicals so as to transform the chemicals from the first equilibrium state to the second combustible state, and also coupled to the igniter to cause ignition and combustion of the combustible chemicals within the combustion zone; and

sensors for detecting seismic waves produced by the seismic sound source.

17. A method of conducting seismological surveys, the method comprising:

positioning a regenerative combustion device at a first location within a subterranean well;

providing electrical current to the regenerative combustion device to cause production of a combustible gas within a combustion zone through electrolysis, and to ignite the combustion of the combustible gas within the combustion zone; and

detecting seismic waves produced in the ground as a result of the combustion.

23. A method of performing regenerative combustion, the method comprising:

forming a combustion chamber;

disposing a liquid electrolyte within the combustion chamber;

creating a combustible mixture from at least a part of the liquid electrolyte;

igniting the combustible mixture and producing combustion products therefrom;

retaining the combustion products within the combustion chamber; and

reversibly transforming the combustion products back into liquid electrolyte.