Heating hydrocarbon containing formations in a spiral startup staged sequence

• US 7,631,690 B2
• Filed: 10/19/2007
• Issued: 12/15/2009
• Est. Priority Date: 10/20/2006
• Status: Active Grant

• Current Assignee: Shell Oil Company (Shell Plc)
• Original Assignee: Shell Oil Company (Shell Plc)
• Inventors: Vinegar, Harold J., Miller, David Scott
• Primary Examiner(s): SUCHFIELD, GEORGE A
• Application Number:
  US11/975,701
• Publication Number:
  US 20080217015A1
• Time in Patent Office: 788 Days
• Field of Search: 166/57, 166/245, 166/272.1, 166/272.3, 166/302
• US Class Current: 166/245
• CPC Class Codes: C10G 1/02 by distillation
• CPC Class Codes: C10G 2300/4037 In-situ processes
• CPC Class Codes: E21B 36/04 using electrical heaters
• CPC Class Codes: E21B 43/243 Combustion in situ
• CPC Class Codes: E21B 43/30 Specific pattern of wells, e.g. optimising the spacing of wells
• CPC Class Codes: E21B 47/0228 using electromagnetic energy or detectors therefor

Abstract

Methods for treating a hydrocarbon containing formation are described herein. Methods may include treating a first zone of the formation. Treatment of a plurality of zones of the formation may be begun at selected times after the treatment of the first zone begins. The treatment of at least two successively treated zones may begin at a selected time after treatment of the previous zone begins. At least two of the successively treated zones may be adjacent to the zone treated previously. The successive treatment of the zones proceeds in an outward, substantially spiral sequence from the first zone so that the treatment of the zones may move substantially spirally outwards towards a boundary of the treatment area.

Claims

1. A method for treating a hydrocarbon containing formation, comprising:

treating a first zone inside a treatment area of the formation;

beginning treatment of a plurality of zones of the formation at selected times after the treatment of the first zone begins, the treatment of at least two successively treated zones beginning at a selected time after treatment of the previous zone begins;

wherein at least two of the successively treated zones are adjacent to the zone treated previously;

wherein the successive treatment of the zones proceeds in an outward, substantially spiral sequence from the first zone such that the treatment of the zones moves substantially spirally outwards towards a boundary of the treatment area;

wherein treatment of at least two of the zones comprises;

providing heat from one or more heaters located in two or more first sections of the zone;

allowing some of the heat to transfer from at least two of the first sections to two or more second sections of the zone;

wherein the first sections and the second sections are arranged in a checkerboard pattern within the zone, the checkerboard pattern having at least one of the first sections substantially surrounded by three or more of the second sections and at least one of the second sections substantially surrounded by three or more of the first sections; and

producing at least some hydrocarbons from the second sections, wherein at least some of the hydrocarbons produced in the second sections comprise fluids initially in the first sections.

2. The method of claim 1, wherein the first zone is at or near a center of the treatment area.

3. The method of claim 1, further comprising providing heat from one or more heaters located in the second sections.

4. The method of claim 1, further comprising providing a barrier around at least a portion of the treatment area.

5. The method of claim 1, further comprising allowing outer zones of the formation to expand inwards into previously treated zones to inhibit shearing in the formation.

6. The method of claim 1, wherein the outward spiral sequence inhibits expansion stresses in the formation.

7. The method of claim 1, further comprising providing one or more support portions in the formation between one or more of the zones.

8. The method of claim 1, wherein the support portions provide support against geomechanical shifting, shearing, and/or expansion stress in the formation.

9. The method of claim 1, further comprising allowing at least some fluids to flow from the first sections to the second sections.

10. The method of claim 1, further comprising allowing at least some fluids to flow from the first sections to the second sections to convectively transfer heat from the first sections to the second sections.

11. The method of claim 1, wherein the provided heat increases the permeability of at least one of the first sections and/or at least one of the second sections.

12. The method of claim 1, wherein the provided heat mobilizes at least some hydrocarbons in the first sections and/or the second sections.

13. The method of claim 1, wherein the provided heat pyrolyzes at least some hydrocarbons in the first sections and/or the second sections.

14. The method of claim 1, further comprising dewatering at least one of the first sections and/or at least one of the second sections prior to providing heat to the formation.

15. The method of claim 1, wherein the volume of at least one of the first sections is between about 70% and about 130% of the volume of at least one of the second sections.

16. The method of claim 1, further comprising injecting a fluid into the first sections to move at least some of the hydrocarbons into the second sections.

17. The method of claim 1, wherein superposition of heat from the first heaters does not overlap a portion of at least one of the second sections proximate at least one production well.

18. The method of claim 1, further comprising controlling a temperature of a portion of at least one of the second sections proximate at least one production well such that the temperature is at most about 200°

C.

19. The method of claim 1, further comprising reducing or turning off production in at least one production well in at least one of the second sections when a temperature in a portion proximate the production well reaches a temperature of about 200°

C.