Method of direct steam generation using an oxyfuel combustor

• US 20100224363A1
• Filed: 03/04/2010
• Published: 09/09/2010
• Est. Priority Date: 03/04/2009
• Status: Active Grant

• Current Assignee: World Energy Systems
• Original Assignee: World Energy Systems
• Inventors: Propp, Murray, Anderson, Roger E., Pronske, Keith L.
• Granted Patent: US 8,522,871 B2
• Time in Patent Office: Days
• US Class Current: 166/266
• CPC Class Codes: E21B 43/164 Injecting CO2 or carbonated water in combination with organic material C09K8/594
• CPC Class Codes: E21B 43/24 using heat, e.g. steam injection
• CPC Class Codes: E21B 43/2406 Steam assisted gravity drainage [SAGD]
• CPC Class Codes: E21B 43/2408 SAGD in combination with other methods
• CPC Class Codes: E21B 43/34 Arrangements for separating materials produced by the well
• CPC Class Codes: F22B 1/003 using combustion of hydrogen with oxygen power plants using steam created by combustion of hydrogen with oxygen F01K25/005
• CPC Class Codes: F22B 1/1853 coming in direct contact with water in bulk or in sprays

Abstract

A gas generator is provided with a combustion chamber into which oxygen and a hydrogen containing fuel are directed for combustion therein. The gas generator also includes water inlets and an outlet for a steam and CO₂ mixture generated within the gas generator. The steam and CO₂ mixture can be used for various different processes, with some such processes resulting in recirculation of water from the processor back to the water inlets of the gas generator. In one process a hydrocarbon containing subterranean space is accessed by a well and the steam and CO₂ mixture is directed into the well to enhance removability of hydrocarbons within the subterranean space. Fluids are then removed from the subterranean space include hydrocarbons and water, with a portion of the hydrocarbons then removed in a separator/recovery step. The resulting hydrocarbon removal system can operate with no polluting emissions and with no water requirements.

Claims

1. A method for recovery of hydrocarbons from a subterranean space, including the steps of:

identifying a subterranean space with hydrocarbons therein;

identifying a well extending into the subterranean space;

operating a gas generator having a combustion chamber, an oxygen enriched oxidizer inlet, a fuel inlet, at least one water inlet and a steam and CO₂ mixture outlet;

generating oxygen enriched oxidizer by separating air constituents to produce the oxygen enriched oxidizer having a grater proportion of oxygen than is present in air;

coupling the steam and CO₂ mixture outlet of the gas generator upstream from the well of said identifying a well step;

directing at least a portion of the steam and CO₂ mixture into the subterranean space through the well;

allowing the steam and CO₂ mixture to interact with hydrocarbons within the subterranean space to enhance a removability of the hydrocarbons; and

removing at least a portion of the hydrocarbons from the subterranean space after the hydrocarbon'"'"'s removability is enhanced by contact with the steam and CO₂ mixture during said allowing step.

2. The method of claim 1 wherein said removing step includes removing fluids from the subterranean space, the fluids including a combination of water and hydrocarbons, at least a portion of the water being water condensed from the steam introduced into the subterranean space by said directing step.

3. The method of claim 2 wherein said removing step includes the step of pumping fluids from the subterranean space.

4. The method of claim 2 wherein said removing step includes draining fluids from the subterranean space by gravity.

5. The method of claim 2 including the further step of separating at least a portion of hydrocarbons from at least a portion of the water after said removing step.

6. The method of claim 5 wherein said separating step is followed by the step of recirculating the water after reduction of hydrocarbons within the water during said separating step, said recirculating step including recirculating at least a portion of the water to the at least one water inlet of the gas generator.

7. The method of claim 6 wherein said operating step includes configuring the gas generator is adapted to combust both fuel entering the combustion chamber through the fuel inlet and hydrocarbons entering the combustion chamber along with water at'"'"' the at least one water inlet.

8. The method of claim 7 wherein said operating step includes configuring the gas generator to include multiple water inlets into the combustion chamber of the gas generator, at least one of the water inlets located adjacent the oxidizer inlet and the fuel inlet, and at least one of the water inlets spaced from the oxidizer inlet and the fuel inlet.

9. The method of claim 8 wherein said operating step includes configuring the gas generator to include multiple water inlets spaced from the oxidizer inlet and the fuel inlet and spaced from each other to enter the gas generator at locations within the gas generator having different temperatures.

10. The method of claim 6 wherein said recirculating step includes interposing a softener upstream of the at least one water inlet of the gas generator to soften the water before entry into the gas generator.

11. The method of claim 1 including the further step of throttling the steam and CO₂ mixture downstream of the outlet of the gas generator to a lower pressure and to a higher amount of super heat before said directing step.

12. A method for direct steam and CO₂ mixed gas generation and utilization, including the steps of:

providing a gas generator having a combustion chamber, an oxygen inlet leading into the combustion chamber, a fuel inlet leading into the combustion chamber, a plurality of water inlets leading into the gas generator and a steam and CO₂ mixture outlet from the combustion chamber;

configuring the gas generator to include multiple adjacent chambers with separate water inlets passing into the gas generator between the adjacent chambers, such that temperatures in the adjacent chambers are progressively lower as distance from the combustion chamber increases; and

coupling the steam and CO₂ mixture outlet of the gas generator to an inlet of a steam and CO₂ utilizing processor.

13. The method of claim 12 including the further step of recirculating water to the gas generator water inlets from a discharge of the processor, such that the method is at least partially a closed loop process.

14. The method of claim 13 including the further step of configuring the processor to include a separate water discharge and carbon dioxide discharge, the water discharge coupled to said gas generator water inlets for recirculating of water to the gas generator water inlet.

15. The system of claim 12 including the further step of locating a separator between the steam and CO₂ mixture outlet of the gas generator and the processor, the separator adapted to separate non-steam and CO₂ constituents from the steam and CO₂ mixture.

16. The method of claim 12 including the further step of configuring the processor to be in the form of a steam assisted gravity drain site including a hydrocarbon containing subterranean space and a well extending into the subterranean space, the well coupled to the steam and CO₂ mixture outlet of the gas generator.

17. The method of claim 16 including the further step of recirculating at least a portion of water exiting from a drain of the steam assisted gravity drain site to the water inlets of the gas generator.

18. The method of claim 16 including the further step of recirculating at least a portion of water and hydrocarbons exiting from a drain of the steam assisted gravity drain site to the water inlets of the gas generator;

and

combusting at least a portion of the hydrocarbons contained within the water within the gas generator.

19. A hydrocarbon production system, comprising in combination:

a gas generator having a combustion chamber with an oxygen inlet passing into the combustion chamber, a fuel inlet passing into the combustion chamber and at least one water inlet passing into the gas generator, and with a steam and carbon dioxide mixture outlet;

a well head accessing a subterranean space containing hydrocarbons;

an outlet from the subterranean space adapted to remove water and hydrocarbons from the subterranean space;

a hydrocarbon separator coupled to said outlet from the subterranean space the hydrocarbon separator adapted to separate at least a portion of the water from at least a portion of the hydrocarbons; and

a water recirculation line extending from the hydrocarbon separator to the at least one water inlet of the gas generator.

20. The system of claim 19 wherein a softener is interposed between said hydrocarbon separator and said at least one water inlet of said gas generator along said water recirculation line, said softener adapted to soften the water before the water enters the gas generator.

21. The system of claim 19 wherein a separator is provided downstream of the gas generator, said salt separator adapted to separate non-water and non-CO₂ constituents within the water and CO₂ mixture exiting said gas generator through said outlet.

22. The system of claim 19 wherein a reheater is located downstream of said gas generator outlet, said reheater adapted to increase a heat of the steam and carbon dioxide mixture downstream of said gas generator and upstream of said well head.

23. The system of claim 19 wherein a pressure reducing valve is located downstream of said outlet of said gas generator, said pressure reducing valve adapted to decrease a pressure of the steam and CO₂ mixture and increase an amount of super heat of the steam in the steam and CO₂ mixture.

24. The system of claim 19 wherein said hydrocarbon separator includes a water outlet upstream of said at least one water inlet of said gas generator, said hydrocarbon separator adapted to only partially separate hydrocarbons from water removed from the subterranean space with hydrocarbons remaining in the water at said water outlet, said gas generator adapted to combust at least a portion of the hydrocarbons remaining in the water and entering said gas generator through said at least one water inlet.