Systems and methods for in situ resistive heating of organic matter in a subterranean formation

Patent metadata

Field	Value
Publication number	US-9394772-B2
Application number	US-201414489113-A
Country	US
Kind code	B2
Filing date	Sep 17, 2014
Priority date	Nov 7, 2013
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

A method for pyrolyzing organic matter in a subterranean formation includes powering a first generation in situ resistive heating element within an aggregate electrically conductive zone at least partially in a first region of the subterranean formation by transmitting an electrical current between a first electrode pair in electrical contact with the first generation in situ resistive heating element to pyrolyze a second region of the subterranean formation, adjacent the first region, to expand the aggregate electrically conductive zone into the second region, wherein the expanding creates a second generation in situ resistive heating element within the second region and powering the second generation in situ resistive heating element by transmitting an electrical current between a second electrode pair in electrical contact with the second generation in situ resistive heating element to generate heat with the second generation in situ resistive heating element within the second region.

First claim

The invention claimed is:

1. A method for pyrolyzing organic matter in a subterranean formation, the method comprising:
powering a first generation in situ resistive heating element within an aggregate electrically conductive zone at least partially in a first region of the subterranean formation by transmitting an electrical current between a first electrode and a second electrode of a first electrode pair in electrical contact with the first generation in situ resistive heating element to pyrolyze a second region of the subterranean formation, adjacent the first region, to expand the aggregate electrically conductive zone into the second region, wherein the expanding creates a second generation in situ resistive heating element within the second region; and
powering the second generation in situ resistive heating element by transmitting an electrical current between a first and a second electrode of a second electrode pair in electrical contact with the second generation in situ resistive heating element to generate heat with the second generation in situ resistive heating element within the second region, wherein the first electrode of the second electrode pair extends within the second region, and the second electrode of the second electrode pair is the first electrode of the first electrode pair or the second electrode of the first electrode pair.

2. The method of claim 1 , further comprising pyrolyzing the first region of the subterranean formation to create the first generation in situ resistive heating element within the first region.

3. The method of claim 2 , further comprising placing in the subterranean formation at least one electrode well prior to creating the first generation in situ resistive heating element, wherein the electrode well is configured to contain at least one electrode of the first electrode pair or the second electrode pair.

4. The method of claim 3 , wherein the placing in the subterranean formation at least one electrode well includes placing two electrodes within the electrode well, and wherein the electrode well includes a wellbore heater between the two electrodes.

5. The method of claim 2 , further comprising placing at least one electrode of the second electrode pair into electrical contact with the second region prior to creating the first generation in situ resistive heating element.

6. The method of claim 2 , wherein the pyrolyzing the first region includes increasing an average electrical conductivity of the first region.

7. The method of claim 2 , wherein the pyrolyzing the first region results in an average electrical conductivity of the first region of at least 10 −4 S/m.

8. The method of claim 1 , further comprising placing at least one electrode of the second electrode pair into electrical contact with the second region prior to creating the second generation in situ resistive heating element.

9. The method of claim 1 , further comprising placing in the subterranean formation at least one electrode well prior to creating the second generation in situ resistive heating element, wherein the electrode well is configured to contain at least one electrode of the first electrode pair or the second electrode pair.

10. The method of claim 1 , wherein the powering the first generation in situ resistive heating element includes expanding the aggregate electrically conductive zone into electrical contact with at least one electrode of the second electrode pair.

11. The method of claim 1 , wherein the powering the first generation in situ resistive heating element includes establishing electrical contact between the aggregate electrically conductive zone and at least one electrode of the second electrode pair.

12. The method of claim 1 , wherein the powering the first generation in situ resistive heating element includes increasing a degree of electrical contact between the aggregate electrically conductive zone and at least one electrode of the second electrode pair.

13. The method of claim 1 , wherein at least one electrode of the first electrode pair includes an elongated contact portion, wherein the powering the first generation in situ resistive heating element includes expanding the aggregate electrically conductive zone along a length of the elongated contact portion.

14. The method of claim 1 , further comprising ceasing the powering the first generation in situ resistive heating element before the powering the second generation in situ resistive heating element.

15. The method of claim 1 , further comprising ceasing the powering the first generation in situ resistive heating element during the powering the second generation in situ resistive heating element.

16. The method of claim 1 , wherein the powering the first generation in situ resistive heating element includes regulating expansion of the aggregate electrically conductive zone by controlling at least one of a duration of the powering, a magnitude of electrical power, and a magnitude of electrical current.

17. The method of claim 1 , wherein the powering the second generation in situ resistive heating element includes regulating expansion of the aggregate electrically conductive zone by controlling at least one of a duration of the powering, a magnitude of electrical power, and a magnitude of electrical current.

18. The method of claim 1 , wherein the powering the first generation in situ resistive heating element includes pyrolyzing a plurality of second regions of the subterranean formation, each adjacent the first region, to create a second generation in situ resistive heating element within each second region, wherein the pyrolyzing the plurality of second regions expands the aggregate electrically conductive zone into each of the second regions; and
wherein the powering the second generation in situ resistive heating element includes powering at least two second generation in situ resistive heating elements by transmitting an electrical current between at least two second electrode pairs, each second electrode pair in electrical contact with a distinct second generation in situ resistive heating element, to heat the second regions.

19. The method of claim 18 , wherein the pyrolyzing the plurality of second regions includes expanding the aggregate electrically conductive zone into electrical contact with at least one electrode of each second electrode pair.

20. The method of claim 18 , wherein the pyrolyzing the plurality of second regions includes establishing electrical contact between the aggregate electrically conductive zone and at least one electrode of each second electrode pair.

21. The method of claim 18 , wherein the pyrolyzing the plurality of second regions includes increasing a degree of electrical contact between the aggregate electrically conductive zone and at least one electrode of each second electrode pair.

22. The method of claim 1 , further comprising determining a desired geometry of the aggregate electrically conductive zone prior to the powering the first generation in situ resistive heating element, at least partially based on data relating to at least one of the subterranean formation and an organic matter in the subterranean formation.

23. The method of claim 1 , further comprising determining a desired geometry of the aggregate electrically conductive zone prior to the powering the first generation in situ resistive heating element, at least partially based on data relating to an organic matter in the subterranean formation.

Assignees

• Meurer William P
• Fang Chen
• Gallo Federico G
• Hoda Nazish
• Lin Michael W
• Exxonmobil Upstream Res Co

Inventors

• Meurer William P
• Fang Chen
• Gallo Federico G
• Hoda Nazish
• Lin Michael W

Classifications

• E21B36/04

  using electrical heaters · CPC title

• E21B43/2401 Primary

  by means of electricity · CPC title