LOAD CONTROL SYSTEM AND METHOD FOR HYDROCARBON PUMP ENGINE

• US 20180274335A1
• Filed: 03/24/2017
• Published: 09/27/2018
• Est. Priority Date: 03/24/2017
• Status: Active Grant

• Current Assignee: Husky Oil Operations Limited (Cenovus Energy Incorporated)
• Original Assignee: Husky Oil Operations Limited (Cenovus Energy Incorporated)
• Inventors: Hudson, Skyler Jonathan
• Granted Patent: US 10,541,633 B2
• Time in Patent Office: Days
• CPC Class Codes: E21B 43/121 Lifting well fluids monitoring of down-hole pump systems E21B47/008
• CPC Class Codes: F02D 19/027 Determining the fuel pressure, temperature or volume flow, the fuel tank fill level or a valve position
• CPC Class Codes: F02D 2200/0406 Intake manifold pressure
• CPC Class Codes: F02D 2200/0602 Fuel pressure
• CPC Class Codes: F02D 2250/24 by using an external load, e.g. a generator
• CPC Class Codes: F02D 29/04 peculiar to engines driving pumps
• CPC Class Codes: F02D 29/06 peculiar to engines driving electric generators
• CPC Class Codes: F02D 31/001 Electric control of rotation speed
• CPC Class Codes: F02D 41/0027 the fuel being gaseous non-electrical control F02D19/02
• CPC Class Codes: H02K 7/1815 structurally associated with reciprocating piston engines general aspects of generating sets, e.g. housing, F02B63/04
• CPC Class Codes: H02P 9/04 Control effected upon non-electric prime mover and dependent upon electric output value of the generator
• CPC Class Codes: Y02T 10/30 Use of alternative fuels, e.g. biofuels

Abstract

Systems and methods for reducing produced gas venting from a hydrocarbon well, in which the engine driving the pump burns produced gas from the well, the engine made to increase its throttle to burn more gas in response to an increased gas pressure indicator, and an external load such as a generator directed to increase the load on the engine and maintain the engine operating within a desired revolutions-per-minute range to avoid redline condition.

Claims

1. A method for reducing gas venting from a hydrocarbon production facility, the facility configured for production of oil using a pump powered by an engine and for production of gas, the method comprising the steps of:

a. producing the oil and the gas to surface;

b. directing at least some of the gas to the engine to power the engine, the engine configured for operation within an optimal RPM range;

c. monitoring pressure of the gas being produced; and

d. in response to an increased pressure of the gas as determined by the monitoring of the gas pressure, increasing an external load on the engine to maintain the engine within the optimal RPM range while increasing engine throttle to burn the gas at the increased pressure.

2. The method of claim 1 further comprising using a programmable logic controller for the step of increasing the engine throttle to burn the gas at the increased pressure and for the step of increasing the external load on the engine.

3. The method of claim 1 where a governor is used to maintain the engine within the optimal RPM range while increasing engine throttle to burn the gas at the increased pressure, the method comprising using a programmable logic controller for the step of increasing the external load on the engine, and the governor is used to increase the engine throttle and maintain the engine within the optimal RPM range.

4. The method of claim 1 wherein a gas tree is used for the step of directing at least some of the gas to the engine to power the engine.

5. The method of claim 4 wherein the step of monitoring the pressure of the gas being produced is achieved by a sensor located on the gas tree.

6. The method of claim 1 wherein the step of increasing the external load on the engine comprises connecting a generator to the engine to draw power from the engine.

7. The method of claim 6 wherein the generator generates electrical energy, the method comprising the further step of dissipating the electrical energy using a load bank.

8. The method of claim 6 wherein the generator generates electrical energy, the method comprising the further step of dissipating the electrical energy by sending the electrical energy to a utility grid.

9. The method of claim 1 comprising the further steps of determining a maximum allowable gas pressure and allowing venting of a portion of the gas to reduce the gas pressure below the maximum allowable gas pressure.

10. The method of claim 9 further comprising using a regulator to allow the venting of the portion of the gas.

11. The method of claim 1 wherein when the monitoring of the gas pressure indicates a reduced pressure of the gas available to the engine, the method comprises the step of reducing the engine throttle while decreasing the external load to maintain the RPM within the optimal RPM range.

12. An engine load control system for use with a hydrocarbon production facility, the facility configured for production of oil and gas, the system comprising:

a pump for producing the oil;

an engine connected to the pump for powering the pump, the engine powered at least partly by the gas produced by the facility, the engine configured for operation within an optimal RPM range having an upper level, the engine comprising a monitor for detecting RPM of the engine;

a gas supply subsystem for supplying the gas to the engine, the gas supply subsystem comprising a sensor for detecting pressure of the gas in the gas supply subsystem;

a generator connected to the engine for providing a load on the engine; and

a programmable logic controller configured to receive an RPM signal from the monitor and a gas pressure signal from the sensor, the controller configured to control the RPM of the engine and operation of the generator;

wherein when the gas pressure signal indicates an increase in pressure of the gas, the controller directs the engine to increase engine throttle to burn the gas at the increased pressure; and

wherein when the RPM signal indicates that the engine has reached the upper level of the optimal RPM range due to the increased engine throttle, the controller directs the generator to operate so as to increase the load on the engine and consequently maintain the engine within the optimal RPM range while the gas is burned at the increased pressure.

13. The system of claim 12 wherein the generator is connected to a crankshaft of the engine.

14. The system of claim 12 wherein the pump is a hydraulic pump.

15. The system of claim 14 wherein the hydraulic pump is connected to the engine, and the generator is connected to the engine via the hydraulic pump.

16. The system of claim 14 wherein the generator is connected to the engine and the hydraulic pump is connected to the generator.

17. The system of claim 12 wherein the generator converts mechanical energy from the engine to electrical energy.

18. The system of claim 17 wherein the electrical energy is dissipated using a load bank.

19. The system of claim 17 wherein the electrical energy is dissipated by a tie-in to a utility grid.

20. The system of claim 12 further comprising an oil output line from the facility.

21. The system of claim 12 wherein the gas supply subsystem comprises a gas tree, and the sensor is on the gas tree.

22. The system of claim 21 wherein the gas tree directs the produced gas to the engine.

23. The system of claim 21 wherein the gas supply subsystem further comprises a regulator for setting a vent gas pressure.

24. The system of claim 12 wherein the gas supply subsystem further comprises a gas volume flow rate monitor.

25. The system of claim 12 wherein the controller is manually operable by a touchscreen.

26. The system of claim 12 wherein the controller is used to set a plurality of setpoint pressures and corresponding RPM levels.

27. The system of claim 12 wherein when the gas pressure signal indicates a decrease in pressure of the gas, the controller directs the engine to decrease the engine throttle and directs the generator to operate so as to decrease the load on the engine and consequently maintain the engine within the optimal RPM range.

28. A method for reducing gas venting from a hydrocarbon production facility, the facility configured for production of oil using an engine-powered pump and for production of gas, the method comprising the steps of:

a. producing the oil and the gas to surface;

b. directing the gas to the engine to power the engine;

c. operating the engine within an optimal RPM range;

d. monitoring RPM of the engine;

e. monitoring pressure of the gas available to be directed to the engine;

f. in response to an increased pressure of the gas available to the engine as determined by the monitoring of the pressure of the gas, increasing the engine throttle to burn the increased pressure of the gas; and

g. in response to the RPM of the engine consequently reaching an upper level of the optimal RPM range as determined by the monitoring of the RPM of the engine, increasing an external load on the engine to maintain the engine within the optimal RPM range while burning the gas at the increased pressure.

29. The method of claim 28 wherein a programmable logic controller is used for increasing the RPM of the engine to burn the increased pressure of the gas and for increasing the external load on the engine.

30. The method of claim 28 wherein a gas tree is used for the step of directing the gas to the engine to power the engine.

31. The method of claim 30 wherein the step of monitoring the pressure of the gas being directed to the engine is achieved by a sensor located on the gas tree.

32. The method of claim 28 wherein the step of increasing the external load on the engine comprises connecting a generator to the engine to draw power from the engine.

33. The method of claim 32 wherein the generator generates electrical energy, the method comprising the further step of dissipating the electrical energy using a load bank.

34. The method of claim 32 wherein the generator generates electrical energy, the method comprising the further step of dissipating the electrical energy by sending the electrical energy to a utility grid.

35. The method of claim 28 comprising the further steps of determining a maximum allowable gas pressure and allowing venting of a portion of the gas to reduce the gas pressure below the maximum allowable gas pressure.

36. The method of claim 35 comprising using a regulator to allow the venting of the portion of the gas.

37. The method of claim 28 wherein when the monitoring of the gas pressure indicates a reduced pressure of the gas available to the engine, the method comprises the step of reducing the throttle of the engine while decreasing the external load to maintain the RPM within the optimal RPM range.

38. A system for maintaining operation of an engine within a predetermined engine RPM range, the engine powered at least in part by produced subsurface gas and for powering a pump for producing subsurface oil, the system comprising:

a programmable logic controller for setting the predetermined engine RPM range, the range comprising an upper level;

a gas supply subsystem for directing the produced gas to the engine for powering the engine, the gas supply subsystem comprising a sensor for detecting pressure of the gas in the gas supply subsystem and a gas pressure signal generator for sending a gas pressure signal to the programmable logic controller;

an engine RPM control subsystem comprising a monitor for detecting RPM of the engine and an engine RPM signal generator for sending an engine RPM signal to the programmable logic controller; and

an external load subsystem connected to the engine for providing a load on the engine;

wherein when the gas pressure signal indicates an increase in pressure of the gas available for consumption by the engine, the programmable logic controller directs the engine to increase throttle to burn the gas at the increased pressure; and

wherein when the engine RPM signal indicates that the engine has reached the upper level of the range due to the increased throttle, the programmable logic controller directs the external load subsystem to provide the load on the engine and consequently maintain the engine within the predetermined engine RPM range while the gas is burned at the increased pressure.

39. The system of claim 38 wherein the load comprises a generator connected to the engine.

40. The system of claim 39 wherein the generator is connected to a crankshaft of the engine.

41. The system of claim 38 wherein the pump is a hydraulic pump.

42. The system of claim 41 wherein the load comprises a generator, the hydraulic pump is connected to the engine, and the generator is connected to the engine via the hydraulic pump.

43. The system of claim 41 wherein the load comprises a generator, the generator is connected to the engine and the hydraulic pump is connected to the generator.

44. The system of claim 39 wherein the generator converts mechanical energy from the engine to electrical energy.

45. The system of claim 44 wherein the electrical energy is dissipated using a load bank.

46. The system of claim 44 wherein the electrical energy is dissipated by a tie-in to a utility grid.

47. The system of claim 38 further comprising an oil output line.

48. The system of claim 38 wherein the gas supply subsystem comprises a gas tree, and the sensor is on the gas tree.

49. The system of claim 48 wherein the gas tree directs the produced gas to the engine.

50. The system of claim 38 wherein the gas supply subsystem further comprises a regulator for setting a vent gas pressure.

51. The system of claim 38 wherein the programmable logic controller is manually operable by a touchscreen.

52. The system of claim 38 wherein the programmable logic controller is used to set a plurality of setpoint pressures and corresponding engine throttle levels.

53. The system of claim 38 wherein when the gas pressure signal indicates a decrease in pressure of the gas, the programmable logic controller directs the engine to decrease the engine throttle and directs the external load subsystem to decrease the load on the engine and consequently maintain the engine within the predetermined engine RPM range.

54. An engine load control system for use with a hydrocarbon production facility, the facility configured for production of oil and gas, the system comprising:

a pump for producing the oil;

an engine connected to the pump for powering the pump, the engine powered at least partly by the gas produced by the facility, the engine configured for operation within an optimal RPM range;

a gas supply subsystem for supplying the gas to the engine, the gas supply subsystem comprising a sensor for detecting pressure of the gas in the gas supply subsystem;

a generator connected to the engine for providing a load on the engine;

a governor connected to the engine to control RPM of the engine; and

a programmable logic controller configured to receive a gas pressure signal from the sensor;

wherein when the gas pressure signal indicates an increase in pressure of the gas, the controller directs the generator to increase the load on the engine to burn the gas at the increased pressure, and the governor maintains the RPM of the engine within the optimal RPM range while the gas is burned at the increased pressure.

55. The system of claim 54 wherein the generator is connected to a crankshaft of the engine.

56. The system of claim 54 wherein the pump is a hydraulic pump.

57. The system of claim 56 wherein the hydraulic pump is connected to the engine and the generator is connected to the engine via the hydraulic pump.

58. The system of claim 56 wherein the generator is connected to the engine and the hydraulic pump is connected to the generator.

59. The system of claim 54 wherein the generator converts mechanical energy from the engine to electrical energy.

60. The system of claim 59 wherein the electrical energy is dissipated using a load bank.

61. The system of claim 59 wherein the electrical energy is dissipated by a tie-in to a utility grid.

62. The system of claim 54 further comprising an oil output line from the facility.

63. The system of claim 54 wherein the controller is manually operable by a touchscreen.

64. The system of claim 54 wherein the gas supply subsystem comprises a gas tree, and the sensor is on the gas tree.

65. The system of claim 64 wherein the gas tree directs the produced gas to the engine.

66. The system of claim 64 wherein the gas tree further directs some of the produced gas to tank burners for heating emulsion used by the facility.

67. The system of claim 54 wherein the gas supply subsystem further comprises a regulator for setting a vent gas pressure.

68. The system of claim 54 wherein the gas supply subsystem further comprises a gas volume flow rate monitor.

69. The system of claim 54 wherein when the gas pressure signal indicates a decrease in pressure of the gas, the controller directs the generator to operate so as to decrease the load on the engine and consequently maintain the engine within the optimal RPM range.