Solution mining and in situ treatment of nahcolite beds

• US 8,240,774 B2
• Filed: 10/13/2008
• Issued: 08/14/2012
• Est. Priority Date: 10/19/2007
• Status: Expired due to Fees

• Current Assignee: Shell Oil Company (Shell Plc)
• Original Assignee: Shell Oil Company (Shell Plc)
• Inventors: Vinegar, Harold J.
• Primary Examiner(s): Kreck, John
• Application Number:
  US12/250,373
• Publication Number:
  US 20090200854A1
• Time in Patent Office: 1,401 Days
• Field of Search: 299/4, 299/5
• US Class Current: 299/4
• CPC Class Codes: E21B 36/04 using electrical heaters
• CPC Class Codes: E21B 43/24 using heat, e.g. steam injection
• CPC Class Codes: E21B 43/30 Specific pattern of wells, e.g. optimising the spacing of wells
• CPC Class Codes: H01F 27/38 Auxiliary core members; Auxiliary coils or windings
• CPC Class Codes: H01F 29/04 having provision for tap-changing without interrupting the load current
• CPC Class Codes: H01J 37/32926 Software, data control or modelling
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: Y10T 29/49083 Heater type

Abstract

A method for treating a nahcolite containing subsurface formation includes solution mining a first nahcolite bed above a hydrocarbon containing layer using a plurality of first solution mining wells. A second nahcolite bed is solution mined below the hydrocarbon containing layer using a plurality of second solution mining wells. At least one of the first solution mining wells is converted into a production well. The hydrocarbon containing layer is heated using a plurality of heaters. Formation fluid is produced from at least one converted first solution mining well.

Claims

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

solution mining a first nahcolite bed above a hydrocarbon containing layer using a plurality of first solution mining wells;

solution mining a second nahcolite bed below the hydrocarbon containing layer using a plurality of second solution mining wells;

converting at least one of the first solution mining wells into a production well;

heating the hydrocarbon containing layer using a plurality of heaters in one or more heater wellbores, wherein at least a portion of at least one of the heater wellbores passes through the first nahcolite bed;

allowing at least some heated fluids to flow from the hydrocarbon containing layer to the first nahcolite bed along the at least one of the heater wellbores with the portion passing through the first nahcolite bed; and

producing at least some of the heated fluids from the hydrocarbon containing layer through at least one converted first solution mining well.

2. The method of claim 1, wherein formation fluid produced from one or more converted first solution mining wells comprises vaporized formation fluid.

3. The method of claim 1, further comprising converting at least one of the second solution mining wells into a production well, and producing formation fluid from at least one converted second solution mining well.

4. The method of claim 3, wherein formation fluid produced from one or more of the converted second solution mining wells comprises liquid formation fluid.

5. The method of claim 1, wherein a portion of at least one of the heaters extends into the second nahcolite bed.

6. The method of claim 1, wherein the hydrocarbon containing layer comprises oil shale.

7. The method of claim 1, wherein the heaters are configured to raise an average temperature of the hydrocarbon containing layer above a pyrolysis temperature.

8. A method for treating a nahcolite containing subsurface formation, comprising:

solution mining a first nahcolite bed above a hydrocarbon containing layer using a plurality of first solution mining wells;

solution mining a second nahcolite bed below the hydrocarbon containing layer using a plurality of second solution mining wells;

converting at least one of the second solution mining wells into a production well;

heating the hydrocarbon containing layer using a plurality of heaters in one or more heater wellbores, wherein at least a portion of at least one of the heater wellbores passes into the second nahcolite bed;

allowing at least some heated fluids to flow from the hydrocarbon containing layer to the second nahcolite bed along the at least one of the heater wellbores with the portion passing into the second nahcolite bed; and

producing at least some of the heated fluids from the hydrocarbon containing layer through at least one converted second solution mining well.

9. The method of claim 8, wherein formation fluid produced from one or more converted second solution mining wells comprises liquid formation fluid.

10. The method of claim 8, further comprising converting at least one of the first solution mining wells into a production well, and producing formation fluid from at least one converted first solution mining well.

11. The method of claim 10, wherein formation fluid produced from one or more of the converted first solution mining wells comprises vaporized formation fluid.

12. The method of claim 8, wherein a portion of at least one of the heaters extends into the second nahcolite bed.

13. The method of claim 8, wherein the hydrocarbon containing layer comprises oil shale.

14. The method of claim 8, wherein the heaters are configured to raise an average temperature of the hydrocarbon containing layer above a pyrolysis temperature.

15. A method for treating a nahcolite containing subsurface formation, comprising:

solution mining a first nahcolite bed above a treatment area using one or more solution mining wells positioned in the first nahcolite bed;

solution mining a second nahcolite bed below the treatment area using one or more solution mining wells in the second nahcolite bed;

providing heat to the treatment area from heaters in one or more heater wellbores, wherein at least a portion of at least one of the heater wellbores passes through the first nahcolite bed;

converting one or more of the solution mining wells used to solution mine the first nahcolite bed to production wells;

allowing at least some heated fluids to flow from the treatment area to the first nahcolite bed along the at least one of the heater wellbores with the portion passing through the first nahcolite bed; and

producing at least some of the heated fluids from the treatment area through at least one production well in the first nahcolite bed.

16. The method of claim 15, wherein providing heat to the treatment area comprises raising an average temperature of the treatment area above a pyrolysis temperature of hydrocarbons in the treatment area.

17. The method of claim 15, further comprising converting one or more of the solution mining wells used to solution mine the second nahcolite bed to production wells.

18. The method of claim 15, further comprising producing formation fluid through at least one production well in the second nahcolite bed.

19. The method of claim 15, wherein the treatment area comprises an oil shale layer.

20. The method of claim 15, wherein the formation fluid produced from the first nahcolite bed comprises non-condensable hydrocarbons.