DOWNHOLE STEAM GENERATOR AND METHOD OF USE

• US 20110214858A1
• Filed: 03/07/2011
• Published: 09/08/2011
• Est. Priority Date: 03/08/2010
• Status: Active Grant

• Current Assignee: World Energy Systems, Inc.
• Original Assignee: World Energy Systems, Inc.
• Inventors: Johnson, M. Cullen, Castrogiovanni, Anthony Gus, Voland, Randall Todd, Folsom, Blair A., Ware, Charles H.
• Granted Patent: US 8,613,316 B2
• Time in Patent Office: Days
• US Class Current: 166/272.1
• CPC Class Codes: E21B 36/02 using burners
• CPC Class Codes: E21B 43/2406 Steam assisted gravity drainage [SAGD]
• CPC Class Codes: E21B 43/243 Combustion in situ
• CPC Class Codes: F22B 1/22 using combustion under pressure substantially exceeding atmospheric pressure
• CPC Class Codes: F22B 1/26 Steam boilers of submerged-flame type, i.e. the flame being surrounded by, or impinging on, the water to be vaporised , e.g. water in sprays
• CPC Class Codes: F23D 14/22 with separate air and gas feed ducts, e.g. with ducts running parallel or crossing each other

Abstract

A downhole steam generation system may include a burner head assembly, a liner assembly, a vaporization sleeve, and a support sleeve. The burner head assembly may include a sudden expansion region with one or more injectors. The liner assembly may include a water-cooled body having one or more water injection arrangements. The system may be optimized to assist in the recovery of hydrocarbons from different types of reservoirs. A method of recovering hydrocarbons may include supplying one or more fluids to the system, combusting a fuel and an oxidant to generate a combustion product, injecting a fluid into the combustion product to generate an exhaust gas, injecting the exhaust gas into a reservoir, and recovering hydrocarbons from the reservoir.

Claims

1. A downhole steam generation system, comprising:

a burner head assembly having a body with a bore disposed through the body and a sudden expansion region that intersects the bore; and

a liner assembly having a body with one or more fluid paths disposed through the body, a combustion chamber defined by the inner surface of the body, and a fluid injection system.

2. The system of claim 1, further comprising a plate disposed in the bore.

3. The system of claim 1, wherein the sudden expansion region includes a first injection step and a second injection step for injecting a fuel into the combustion chamber, wherein the first injection step include an inner diameter greater than the inner diameter of the bore, and wherein the second injection step includes an inner diameter greater than the inner diameter of the first injection step.

4. The system of claim 3, wherein the first and second injection steps are configured to inject the fuel into the combustion chamber in a direction perpendicular to a longitudinal axis of the bore.

5. The system of claim 3, wherein the first and second injection steps each include a plurality of injectors, and wherein the second injection step includes more injectors than the first injection step.

6. The system of claim 5, wherein the burner head assembly further comprises a first manifold for distributing the fuel to the plurality of injectors of the first injection step, and a second manifold for distributing the fuel to the plurality of injectors of the second injection step, wherein the first and second manifolds comprise fluid paths disposed through the body of the burner head assembly.

7. The system of claim 1, wherein the burner head assembly further comprises a cooling system operable to cool a portion of the body adjacent to the sudden expansion region.

8. The system of claim 7, wherein the cooling system includes one or more fluid paths disposed through the body for circulating a cooling fluid about the sudden expansion region.

9. The system of claim 1, wherein the liner assembly further comprises a first manifold for distributing fluid to the one or more fluid paths disposed through the body of the liner assembly, and a second manifold for collecting the fluid from the one or more fluid paths.

10. The system of claim 9, wherein the second manifold is in fluid communication with the fluid injection system for injecting fluid from the one or more fluid paths into the combustion chamber.

11. The system of claim 1, wherein the fluid injection system comprises a fluid injection strut that is coupled to the body of the liner assembly and that has a plurality of nozzles for injecting fluid into the combustion chamber, away from the combustion chamber, or both into and away from the combustion chamber.

12. The system of claim 1, wherein the fluid injection system comprises a gas-assisted fluid injection arrangement operable to direct fluid from the one or more fluid paths into a gas stream for injection into the combustion chamber.

13. A method of recovering hydrocarbons from a reservoir, comprising:

lowering a system into a first wellbore;

supplying a fuel, an oxidant, and a fluid to the system;

mixing and combusting the fuel and the oxidant in a sudden expansion region of the system to generate a combustion product;

flowing the fluid through one or more flow paths disposed through a liner assembly having a combustion chamber;

injecting the fluid into the combustion chamber containing the combustion product to generate an exhaust gas;

injecting the exhaust gas into the reservoir; and

recovering hydrocarbons from the reservoir.

14. The method of claim 13, wherein injecting the fluid into the combustion chamber comprises injecting atomized fluid droplets into the combustion chamber, away from the combustion chamber, or both into and away from the combustion chamber.

15. The method of claim 13, further comprising recovering hydrocarbons from the reservoir through a second wellbore.

16. The method of claim 15, further controlling an injection rate of the exhaust gas into the reservoir and a production rate of hydrocarbons from the reservoir to thereby control the pressure in the reservoir.

17. The method of claim 13, wherein the exhaust gas comprises oxygen for combustion with hydrocarbons within the reservoir to generate a heated gas mixture within the reservoir.

18. The method of claim 13, wherein the fuel comprises at least one of methane, natural gas, syngas, and hydrogen, wherein the oxidant comprises at least one of oxygen, air, and enriched air, and wherein the fluid comprises at least one of water and steam.

19. The method of claim 18, wherein at least one of the fuel, the oxidant, and the fluid are mixed with a diluent comprising at least one of nitrogen, carbon dioxide, and other inert gases.

20. The method of claim 13, further comprising maintaining a pressure in the reservoir greater than 1200 psi.