Heater pattern for in situ thermal processing of a subsurface hydrocarbon containing formation

• US 10,047,594 B2
• Filed: 01/23/2012
• Issued: 08/14/2018
• Est. Priority Date: 01/23/2012
• Status: Active Grant

• Current Assignee: Genie Ip B.V. (Genie Energy Ltd.)
• Original Assignee: Genie Ip B.V. (Genie Energy Ltd.)
• Inventors: Vinegar, Harold, Nguyen, Scott
• Primary Examiner(s): Harcourt, Brad
• Application Number:
  US14/373,880
• Publication Number:
  US 20150176380A1
• Time in Patent Office: 2,395 Days
• CPC Class Codes: E21B 43/24 using heat, e.g. steam injection
• CPC Class Codes: E21B 43/2401 by means of electricity
• CPC Class Codes: E21B 43/243 Combustion in situ

Abstract

Embodiments of the present invention relate to heater patterns and related methods of producing hydrocarbon fluids from a subsurface hydrocarbon-containing formation (for example, an oil shale formation) where a heater cell may be divided into nested inner and outer zones. Production wells may be located within one or both zones. In the smaller inner zone, heaters may be arranged at a relatively high spatial density while in the larger surrounding outer zone, a heater spatial density may be significantly lower. Due to the higher heater density, a rate of temperature increase in the smaller inner zone of the subsurface exceeds that of the larger outer zone, and a rate of hydrocarbon fluid production ramps up faster in the inner zone than in the outer zone. In some embodiments, a ratio between a half-maximum sustained production time and a half-maximum rise time of a hydrocarbon fluid production function is relatively large.

Claims

1. A system for in-situ production of hydrocarbon fluids from a subsurface hydrocarbon-containing formation, the system comprising:

a heater cell divided into nested inner and outer zones such that an enclosed area ratio between respective areas enclosed by substantially-convex polygon-shaped perimeters of the outer and inner zones is between two and seven, heaters being located at all polygon vertices of inner and outer zone perimeters, inner zone and outer zone heaters being respectively distributed around inner and outer zone centroids such that a heater spatial density in inner zone significantly exceeds that of outer zone, each heater cell further comprising inner-zone production well(s) and outer-zone production well(s) respectively located in the inner and outer zones.

2. The system of claim 1 wherein the area ratio is at least three.

3. The system of claim 1 wherein heaters are located at all polygon vertices of inner and outer zone perimeters.

4. The system of claim 1 wherein an average distance to a nearest heater within the outer zone is equal to between about two and about three times that of the inner zone.

5. The system of claim 1 wherein average distance to a nearest heater within the outer zone is equal to between two and three times that of the inner zone.

6. The system of claim 1 wherein a centroid of inner zone is located in a central portion of the region enclosed by a perimeter of the outer zone.

7. The system of claim 1 wherein at least one-third of inner zone heaters are not located on inner zone perimeter.

8. The system of claim 1 wherein heaters are arranged within inner zone so that inner zone heaters are present on every 72 degree sector thereof for any reference ray orientation.

9. The system of claim 1 wherein each of the inner zone and outer zone perimeters is shaped like a rectangular.

10. A system for in-situ production of hydrocarbon fluids from a subsurface hydrocarbon-containing formation, the system comprising:

a heater cell divided into nested, inner, outer and outer-zone-surrounding (OZS) additional zones by respective polygon-shaped zone perimeters, heaters being located at all polygon vertices of inner, outer and OZS additional zone perimeters, the inner and outer zones defining a first zone pair, the outer and OZS additional zones defining a second zone pair, inner zone heaters, outer zone heaters and OZS additional zone heaters being respectively distributed around inner zone, outer zone and OZS additional zone centroids, wherein for each of the zone pairs;

i. an enclosed area ratio between respective areas enclosed by perimeters of the more outer zone and the more inner zone is between two and seven; and

ii. a heater spacing of the more outer zone significantly exceeds that of the more inner zone.

11. A method of in-situ production of hydrocarbon fluids in a subsurface hydrocarbon-containing formation, the method comprising:

for a plurality of heaters disposed in substantially convex, nested inner and outer zones of the subsurface formation operating the heaters to produce hydrocarbon fluids in situ such that;

i. during an earlier stage of production, hydrocarbon fluids are produced primarily in the inner zone; and

ii. during a later stage of production which commences after at least a majority of hydrocarbon fluids have been produced from the inner zone, hydrocarbon fluids are produced primarily in the outer zone surrounding the inner zone,

wherein at least some of the thermal energy required for hydrocarbon fluid production in the outer zone is supplied by outward flow of thermal energy from the inner zone to the outer zone.

12. The method of claim 11 wherein at least 5% of the thermal energy required for hydrocarbon fluid production in the outer zone is supplied by outward flow of thermal energy from the inner zone to the outer zone.

13. The method of claim 11 wherein at least 10% of the thermal energy required for hydrocarbon fluid production in the outer zone is supplied by outward flow of thermal energy from the inner zone to the outer zone.

14. The method of claim 11 wherein a heater spatial density in the inner zone is at least twice that of the outer zone.

15. The method of claim 11 wherein a heater spatial density in inner zone is at least about three times that of the outer zone.