Claims
- 1. A method for improving hydrocarbon fluid production from a cased wellbore extending into a subterranean formation comprising:
- (a) providing a tubing in said wellbore for conveying liquid nitrogen from the surface to said formation, said tubing having low thermal conductivity and comprised of composite fibers in a polymeric matrix;
- (b) providing a heat transfer barrier between the wellbore casing and the interior of said tubing;
- (c) injecting liquid nitrogen through said tubing to said formation whereby the face of said wellbore adjacent said formation is contacted with liquid nitrogen, and during injection of said liquid nitrogen, flowing a gas down the annulus between said casing and said tubing; and
- (d) producing hydrocarbon fluid from said formation through said wellbore.
- 2. The method of claim 1 wherein a gas is injected into said formation adjacent said wellbore prior to said injection of liquid nitrogen.
- 3. The method of claim 2 wherein water is injected into said formation adjacent said wellbore after said injection of gas and prior to said injection of liquid nitrogen.
- 4. The method of claim 1 wherein said formation adjacent said wellbore is contacted with liquid nitrogen a plurality of times followed by production of hydrocarbon fluid therefrom.
- 5. The method of claim 1 wherein said liquid nitrogen contains an added treatment chemical which is reactive in said formation after injection thereinto.
- 6. The method of claim 1 wherein said liquid nitrogen is injected into said formation at a pressure exceeding the fracture pressure of said formation.
- 7. The method of claim 6 wherein said liquid nitrogen includes water ice particles.
- 8. The method of claim 1 wherein said tubing is formed composite fibers selected from the group consisting of glass, aramid, or carbon.
- 9. The method of claim 1 wherein said tubing is formed of fiber glass in an epoxy matrix.
- 10. A method of improving hydrocarbon fluid production from a wellbore extending into a subterranean formation comprising:
- (a) providing a wellbore from the surface through at least a portion of said formation;
- (b) casing said wellbore from the surface to adjacent the top of said formation;
- (c) providing a tubing string through said wellbore from the surface to a point adjacent said formation;
- (d) charging said formation by injecting a gas down said wellbore and into said formation;
- (e) injecting a slug of water into said formation behind said injected gas;
- (f) injecting a gas behind said water slug to clear water from said tubing and wellbore;
- (g) injecting liquid nitrogen into said formation at fracturing pressure;
- (h) displacing liquid nitrogen into said formation from said tubing and borehole;
- (i) closing said well to enable said liquid nitrogen to warm up and vaporize; and
- (j) opening said well to enable vaporized nitrogen to flow out followed by production of hydrocarbon fluid from said well.
- 11. A method for increasing the permeability of a subterranean formation in the area of a wellbore penetrating said formation comprising:
- (a) providing a casing in said wellbore;
- (b) providing a tubing in said wellbore for conveying liquid nitrogen from the surface to said formation, said tubing having low thermal conductivity and comprised of composite fibers in a polymeric matrix;
- (c) providing a heat transfer barrier between said casing and the interior of said tubing; and
- (d) injecting liquid nitrogen through said tubing to said formation whereby the face of said wellbore is contacted with liquid nitrogen and the permeability of said formation adjacent said wellbore is increased.
- 12. The method of claim 11 wherein a gas is flowed down the annulus between said casing and said tubing during injection of said liquid nitrogen.
- 13. A method for improving hydrocarbon fluid production from a cased wellbore extending into a subterranean formation comprising:
- (a) providing a tubing in said wellbore for conveying liquid nitrogen from the surface to said formation;
- (b) providing a heat transfer barrier between the wellbore casing and the interior of said tubing;
- (c) injecting liquid nitrogen through said tubing to said formation whereby the face of said wellbore adjacent said formation is contacted with liquid nitrogen, said liquid nitrogen containing an added treatment chemical which is reactive in said formation after injection thereinto, and
- (d) producing hydrocarbon fluid from said formation through said wellbore.
- 14. A method for improving hydrocarbon fluid production from a cased wellbore extending into a subterranean formation comprising:
- (a) providing a tubing in said wellbore for conveying liquid nitrogen from the surface to said formation;
- (b) providing a heat transfer barrier between the wellbore casing and the interior of said tubing;
- (c) injecting liquid nitrogen through said tubing into said formation at a pressure exceeding the fracture pressure of said formation to fracture the formation;
- (d) forming ice crystals in the liquid nitrogen which is injected into said formation to serve as a temporary propant and flow diverter when the formation is fractured; and
- (e) producing hydrocarbon fluid from said formation through said wellbore.
RELATED APPLICATION
This application is a continuation in part of application Ser. No. 08/356,593 of Dennis R. Wilson et al filed Dec. 14, 1994; now U.S. Pat. No. 5,464,061.
US Referenced Citations (8)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
356593 |
Dec 1994 |
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