Real-Time Production-Side Monitoring and Control for Heat Assisted Fluid Recovery Applications

• US 20070199696A1
• Filed: 02/27/2006
• Published: 08/30/2007
• Est. Priority Date: 02/27/2006
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Walford, Merrick
• Granted Patent: US 7,448,447 B2
• Time in Patent Office: Days
• US Class Current: 166/250.01
• CPC Class Codes: E21B 43/2406 Steam assisted gravity drainage [SAGD]
• CPC Class Codes: E21B 47/07 Temperature
• CPC Class Codes: E21B 47/135 using light waves, e.g. infrared or ultraviolet waves

Abstract

An automatic control system that protects downhole equipment and surface equipment from high temperatures resulting from the breakthrough of injection vapor. The system operates to derive an estimate of the temperature of production fluid at a location upstream from the downhole equipment. An alarm signal is generated in the event that this temperature exceeds a threshold temperature characteristic of injection vapor breakthrough. Electric power to the downhole equipment is automatically shut off in response to receiving the alarm signal. A bypass valve selectively directs production fluid to a bypass path. The system operates to derive an estimate of the temperature of the production fluid at a location upstream from the surface equipment. An alarm signal is generated when this temperature exceeds a threshold temperature characteristic of injection vapor breakthrough. The bypass valve is automatically controlled to direct production fluid to the bypass path in response to receiving the alarm signal.

Claims

1. An apparatus for use in a heat assisted fluid recovery application that injects hot vaporized fluid in the vicinity of a production well, the production well employing electrically powered downhole equipment to pump production fluid therefrom, the apparatus comprising:

temperature sensor and monitoring means for characterizing temperature of the production fluid at a location upstream from the downhole equipment of the production well;

alarm generation means for generating an alarm signal in the event that said temperature exceeds a threshold temperature characteristic of injection vapor breakthrough; and

control means, operably coupled to said alarm generation means and said downhole equipment, for shutting off supply of electric power to the downhole equipment in response to receiving said alarm signal.

2. An apparatus according to claim 1, further comprising:

alarm clearing means for generating an alarm clear signal in the event that said temperature is characteristic that normal production fluid flow has resumed.

3. An apparatus according to claim 2, wherein:

said control means is operably coupled to said alarm clearing means and controls supply of electric power to the downhole equipment in accordance with a designated control scheme in response receiving said alarm clear signal.

4. An apparatus according to claim 1, wherein:

the temperature sensor and monitoring means comprises an optical fiber that extends down the production well at least to said location upstream from the downhole equipment.

5. An apparatus according to claim 4, wherein:

said temperature sensor and monitoring means derives a temperature measurement at said location upstream from the downhole equipment by optical time-domain reflectometry of optical pulses that propagate along said optical fiber.

6. An apparatus according to claim 1, wherein:

the downhole equipment comprises an electrical submersible pump that is fluidly coupled to a production string that extends to the surface.

7. An apparatus according to claim 1, wherein:

said production fluid comprises recovered heavy oil.

8. An apparatus according to claim 7, wherein:

said recovered heavy oil is extracted from bitumen.

9. An apparatus for use in a heat assisted fluid recovery application that injects hot vaporized fluid in the vicinity of a production well, the production well employing surface equipment that is thermally coupled to the production fluid pumped therefrom, the apparatus comprising:

a bypass path for the production fluid around the surface equipment;

bypass valve means for selectively directing production fluid to said bypass path;

temperature sensor and monitoring means for characterizing temperature of the production fluid at a surface location upstream from the surface equipment of the production well;

alarm generation means for generating an alarm signal in the event that said temperature exceeds a threshold temperature characteristic of injection vapor breakthrough; and

control means, operably coupled to said alarm generation means and said bypass valve means, for controlling said bypass valve means to direct production fluid to said bypass path in response to receiving said alarm signal, thereby avoiding thermal coupling of the production fluid to the surface equipment.

10. An apparatus according to claim 9, further comprising:

alarm clearing means for generating an alarm clear signal in the event that said temperature is characteristic that normal production fluid flow has resumed.

11. An apparatus according to claim 10, wherein:

said control means is operably coupled to said alarm clearing means and operates to deactivate said bypass valve means in response to receiving said alarm clear signal.

12. An apparatus according to claim 9, wherein:

the temperature sensor and monitoring means comprises an optical fiber that extends at least to said surface location upstream from the surface equipment.

13. An apparatus according to claim 12, wherein:

said temperature sensor and monitoring means derives a temperature measurement at said surface location upstream from the surface equipment by optical time-domain reflectometry of optical pulses that propagate along said optical fiber.

14. An apparatus according to claim 9, wherein:

the surface equipment comprises a multiphase flowmeter that analyzes production fluid flowing through a production string that extends down the production well.

15. An apparatus according to claim 9, wherein:

said production fluid comprises recovered heavy oil.

16. An apparatus according to claim 15, wherein:

said recovered heavy oil is extracted from bitumen.

17. A method for use in a heat assisted fluid recovery application that injects hot vaporized fluid in the vicinity of a production well, the production well employing electrically powered downhole equipment to pump production fluid therefrom, the method comprising:

deriving an estimate of the temperature of the production fluid at a location upstream from the downhole equipment of the production well;

generating an alarm signal in the event that said temperature exceeds a threshold temperature characteristic of injection vapor breakthrough; and

shutting off supply of electric power to the downhole equipment in response to receiving said alarm signal.

18. A method according to claim 17, further comprising:

generating an alarm clear signal in the event that said temperature is characteristic that normal production fluid flow has resumed.

19. A method according to claim 18, further comprising:

controlling the supply of electric power to the downhole equipment in accordance with a designated control scheme in response to receiving said alarm clear signal.

20. A method according to claim 17, wherein:

said temperature is derived by optical time-domain reflectometry of optical pulses that propagate along an optical fiber that extends at least to said location upstream from the downhole equipment.

21. A method according to claim 17, wherein:

the downhole equipment comprises an electrical submersible pump that is fluidly coupled to a production string that extends to the surface.

22. A method according to claim 17, wherein:

said production fluid comprises recovered heavy oil.

23. A method according to claim 22, wherein:

said recovered heavy oil is extracted from bitumen.

24. A method for use in a heat assisted fluid recovery application that injects hot vaporized fluid in the vicinity of a production well, the production well employing surface equipment that is thermally coupled to the production fluid pumped therefrom, the method comprising:

providing a bypass path for production fluid around the surface equipment together with a bypass valve for selectively directing production fluid to the bypass path;

deriving an estimate of the temperature of the production fluid at a surface location upstream from the surface equipment of the production well;

generating an alarm signal in the event that said temperature exceeds a threshold temperature characteristic of injection vapor breakthrough; and

controlling said bypass valve to direct production fluid to said bypass path in response to receiving said alarm signal, thereby avoiding thermal coupling of the injection vapor breakthrough to the surface equipment.

25. A method according to claim 24, further comprising:

generating an alarm clear signal in the event that said temperature is characteristic that normal production fluid flow has resumed.

26. A method according to claim 25, further comprising:

deactivating said bypass valve in response to receiving said alarm clear signal.

27. A method according to claim 24, wherein:

said temperature is derived by optical time-domain reflectometry of optical pulses that propagate along an optical fiber that extends to said surface location upstream from the surface equipment.

28. A method according to claim 24, wherein:

the surface equipment comprises a multiphase flowmeter that analyzes production fluid flowing through a production string that extends down the production well.

29. A method according to claim 24, wherein:

said production fluid comprises recovered heavy oil.

30. A method according to claim 29, wherein:

said recovered heavy oil is extracted from bitumen.

31. A system for heat assisted fluid recovery comprising:

at least one injection well and at least one production well, said at least one injection well injecting hot vaporized fluid in the vicinity of the at least one production well, the at least one production well employing electrically powered downhole equipment to pump production fluid therefrom;

temperature sensor and monitoring means for characterizing temperature of the production fluid at a location upstream from the downhole equipment of the production well;

alarm generation means for generating an alarm signal in the event that said temperature exceeds a threshold temperature characteristic of injection vapor breakthrough; and

control means, operably coupled to said alarm generation means and said downhole equipment, for shutting off supply of electric power to the downhole equipment in response to receiving said alarm signal.

32. A system according to claim 31, further comprising:

alarm clearing means for generating an alarm clear signal in the event that said temperature is characteristic that normal production fluid flow has resumed.

33. A system according to claim 32, wherein:

said control means is operably coupled to said alarm clearing means and controls supply of electric power to the downhole equipment in accordance with a designated control scheme in response to receiving said alarm clear signal.

34. A system according to claim 31, wherein:

the temperature sensor and monitoring means comprises an optical fiber that extends down the production well at least to said location upstream from the downhole equipment.

35. A system according to claim 34, wherein:

said temperature sensor and monitoring means derives a temperature measurement at said location upstream from the downhole equipment by optical time-domain reflectometry of optical pulses that propagate along said optical fiber.

36. A system according to claim 31, wherein:

the downhole equipment comprises an electrical submersible pump that is fluidly coupled to a production string that extends to the surface.

37. A system according to claim 31, wherein:

said production fluid comprises recovered heavy oil.

38. A system according to claim 37, wherein:

said recovered heavy oil is extracted from bitumen.

39. A system for heat assisted fluid recovery comprising:

at least one injection well and at least one production well, said at least one injection well injecting hot vaporized fluid in the vicinity of the at least one production well, the at least one production well employing surface equipment that is thermally coupled to the production fluid pumped therefrom;

a bypass path for the production fluid around the surface equipment;

bypass valve means for selectively directing production fluid to said bypass path;

temperature sensor and monitoring means for characterizing temperature of the production fluid at a surface location upstream from the surface equipment of the production well;

alarm generation means for generating an alarm signal in the event that said temperature exceeds a threshold temperature characteristic of injection vapor breakthrough; and

control means, operably coupled to said alarm generation means and said bypass valve means, for controlling said bypass valve means to direct production fluid to said bypass path in response to receiving said alarm signal, thereby avoiding thermal coupling of the production fluid to the surface equipment.

40. A system according to claim 39, further comprising:

alarm clearing means for generating an alarm clear signal in the event that said temperature is characteristic that normal production fluid flow has resumed.

41. A system according to claim 40, wherein:

said control means is operably coupled to said alarm clearing means and operates to deactivate said bypass valve means in response to receiving said alarm clear signal.

42. A system according to claim 39, wherein:

the temperature sensor and monitoring means comprises an optical fiber that extends at least to said surface location upstream from the surface equipment.

43. A system according to claim 42, wherein:

said temperature sensor and monitoring means derives a temperature measurement at said surface location upstream from the surface equipment by optical time-domain reflectometry of optical pulses that propagate along said optical fiber.

44. A system according to claim 39, wherein:

the surface equipment comprises a multiphase flowmeter that analyzes production fluid flowing through a production string that extends down the production well.

45. A system according to claim 39, wherein:

said production fluid comprises recovered heavy oil.

46. A system according to claim 45, wherein:

said recovered heavy oil is extracted from bitumen.

47. An apparatus for use in a heat assisted fluid recovery application that injects hot vaporized fluid in the vicinity of a production well, the production well employing electrically powered downhole equipment to pump production fluid therefrom as well as surface equipment that is thermally coupled to the production fluid pumped therefrom, the apparatus comprising:

a bypass path for the production fluid around the surface equipment;

bypass valve means for selectively directing production fluid to said bypass path;

temperature sensor and monitoring means for characterizing a first temperature of the production fluid at a first location which is upstream from the surface equipment of the production well and for characterizing a second temperature of the production fluid at a second location which is upstream from the downhole equipment;

alarm generation means for generating a first alarm signal in the event that said first temperature exceeds a threshold temperature characteristic of injection vapor breakthrough, and for generating a second alarm signal in the event that said second temperature exceeds a threshold temperature characteristic of injection vapor breakthrough; and

control means, operably coupled to said alarm generation means and said bypass valve means, for controlling said bypass valve means to direct production fluid to said bypass path in response to receiving said first alarm signal, and for shutting off supply of electric power to the downhole equipment in response to receiving said second alarm signal.

48. An apparatus according to claim 47, wherein:

said temperature sensor and monitoring means derives a temperature measurement at said location upstream from the downhole equipment by optical time-domain reflectometry of optical pulses that propagate along an optical fiber that at least extends between said first and second locations.

49. An apparatus for use in a heat assisted fluid recovery application that injects hot vaporized fluid in the vicinity of a production well, the production well employing electrically powered downhole equipment to pump production fluid therefrom, the apparatus comprising:

pressure sensor and monitoring means for characterizing pressure of the production fluid at a location upstream from the downhole equipment of the production well;

alarm generation means for generating an alarm signal in the event that said pressure exceeds a threshold pressure characteristic of injection vapor breakthrough; and

control means, operably coupled to said alarm generation means and said downhole equipment, for shutting off supply of electric power to the downhole equipment in response to receiving said alarm signal.

50. An apparatus for use in a heat assisted fluid recovery application that injects hot vaporized fluid in the vicinity of a production well, the production well employing surface equipment that is thermally coupled to the production fluid pumped therefrom, the apparatus comprising:

a bypass path for the production fluid around the surface equipment;

bypass valve means for selectively directing production fluid to said bypass path;

pressure sensor and monitoring means for characterizing pressure of the production fluid at a surface location upstream from the surface equipment of the production well;

alarm generation means for generating an alarm signal in the event that said pressure exceeds a threshold pressure characteristic of injection vapor breakthrough; and

control means, operably coupled to said alarm generation means and said bypass valve means, for controlling said bypass valve means to direct production fluid to said bypass path in response to receiving said alarm signal, thereby avoiding thermal coupling of the production fluid to the surface equipment.

51. A method for use in a heat assisted fluid recovery application that injects hot vaporized fluid in the vicinity of a production well, the production well employing electrically powered downhole equipment to pump production fluid therefrom, the method comprising:

deriving an estimate of the pressure of the production fluid at a location upstream from the downhole equipment of the production well;

generating an alarm signal in the event that said pressure exceeds a threshold pressure characteristic of injection vapor breakthrough; and

shutting off supply of electric power to the downhole equipment in response to receiving said alarm signal.

52. A method for use in a heat assisted fluid recovery application that injects hot vaporized fluid in the vicinity of a production well, the production well employing surface equipment that is thermally coupled to the production fluid pumped therefrom, the method comprising:

providing a bypass path for production fluid around the surface equipment together with a bypass valve for selectively directing production fluid to the bypass path;

deriving an estimate of the pressure of the production fluid at a surface location upstream from the surface equipment of the production well;

generating an alarm signal in the event that said pressure exceeds a threshold pressure characteristic of injection vapor breakthrough; and

controlling said bypass valve to direct production fluid to said bypass path in response to receiving said alarm signal, thereby avoiding thermal coupling of the injection vapor breakthrough to the surface equipment.