Operating states for fuel processor subsystems

• US 6,759,156 B1
• Filed: 04/04/2003
• Issued: 07/06/2004
• Est. Priority Date: 04/04/2003
• Status: Active Grant

• Current Assignee: Texaco Development Corporation (Chevron Corp.), Texaco Incorporated (Chevron Corp.)
• Original Assignee: Texaco Incorporated (Chevron Corp.)
• Inventors: Wheat, W. Spencer, Mirkovic, Vesna R., Benedetto, Dennis J., To, Hugh N.
• Primary Examiner(s): Le, Hoa Van
• Application Number:
  US10/407,482
• Time in Patent Office: 459 Days
• Field of Search: 429/17, 429/19, 429/20, 429/22, 423/650, 423/652
• US Class Current: 429/423
• CPC Class Codes: C01B 2203/00 Integrated processes for the production of hydrogen or synthesis gas
• CPC Class Codes: C01B 2203/0244 the reforming step being an autothermal reforming step, e.g. secondary reforming processes
• CPC Class Codes: C01B 2203/0283 containing a CO-shift step, i.e. a water gas shift step
• CPC Class Codes: C01B 2203/044 Selective oxidation of carbon monoxide
• CPC Class Codes: C01B 2203/045 Purification by catalytic desulfurisation
• CPC Class Codes: C01B 2203/047 the impurity being carbon monoxide
• CPC Class Codes: C01B 2203/0485 the impurity being a sulfur compound
• CPC Class Codes: C01B 2203/066 with fuel cells
• CPC Class Codes: C01B 2203/0811 by combustion of fuel
• CPC Class Codes: C01B 2203/0844 the non-combustive exothermic reaction being another reforming reaction as defined in groups C01B2203/02 - C01B2203/0294
• CPC Class Codes: C01B 2203/0877 by direct injection of fluid
• CPC Class Codes: C01B 2203/0883 by indirect heat exchange
• CPC Class Codes: C01B 2203/0894 Generation of steam
• CPC Class Codes: C01B 2203/1205 Composition of the feed
• CPC Class Codes: C01B 2203/1241 Natural gas or methane
• CPC Class Codes: C01B 2203/1276 Mixing of different feed components
• CPC Class Codes: C01B 2203/142 At least two reforming, decomposition or partial oxidation steps in series
• CPC Class Codes: C01B 2203/146 At least two purification steps in series
• CPC Class Codes: C01B 2203/1604 Starting up the process
• CPC Class Codes: C01B 2203/1609 Shutting down the process
• CPC Class Codes: C01B 2203/1614 : Controlling the temperature
• CPC Class Codes: C01B 2203/1633 : Measuring the pressure
• CPC Class Codes: C01B 2203/169 : Controlling the feed
• CPC Class Codes: C01B 2203/1695 : Adjusting the feed of the combustion
• CPC Class Codes: C01B 2203/82 : Several process steps of C01B2203/02 - C01B2203/08 integrated into a single apparatus
• CPC Class Codes: C01B 3/382 : Multi-step processes
• CPC Class Codes: C01B 3/48 : followed by reaction of water vapour with carbon monoxide
• CPC Class Codes: H01M 8/04231 : Purging of the reactants
• CPC Class Codes: H01M 8/0618 : Reforming processes, e.g. autothermal, partial oxidation or steam reforming
• CPC Class Codes: Y02E 60/50 : Fuel cells

Abstract

An operational cycle for a fuel processor capable of reforming a fuel, the operational cycle is disclosed. The operational cycle includes: an off state; a manager check state entered into from the off state, and in which the operational readiness of the fuel processor is checked; a preheat state entered into from the manager check state, and in which the fuel processor preheats gases, including the fuel, for mixing into a process feed stream; a startup state entered into from the preheat state, and in which the fuel processor begins operating under start-up conditions; a run state entered into from the startup state, and in which the fuel processor reforms the process feed stream into a reformate under steady-state conditions; and a shutdown state entered into any one of the manager check state, preheat state, startup state, and run state. The operational cycle may be employed in a fuel processor for a fuel cell or a fuel cell power plant.

Claims

1. An operational cycle for a fuel processor capable of reforming a fuel, the operational cycle including:

an off state;

a manager check state entered into from the off state, and in which the operational readiness of the fuel processor is checked;

a preheat state entered into from the manager check state, and in which the fuel processor preheats gases, including the fuel, for mixing into a process feed stream;

a startup state entered into from the preheat state, and in which the fuel processor begins operating under start-up conditions;

a run state entered into from the startup state, and in which the fuel processor reforms the process feed stream into a reformate under steady-state conditions; and

a shutdown state entered into any one of the manager check state, preheat state, startup state, and run state.

2. The operational cycle of claim 1, further comprising at least one of:

a manual state entered into from the off state, and into which an operator can direct operation of the overall system; and

an emergency shutdown state entered into from any one of the manager check state, the startup state, and the run state.

3. The operational cycle of claim 1, wherein the off state comprises at least two of:

displaying a message indicating the cause of the shutdown of a previous operational cycle;

enabling the start of the operational cycle;

transitioning to the manager check state; and

transitioning to the manual state.

4. The operational cycle of claim 1, wherein the off state comprises at least two of:

displaying a message indicating the cause of the shutdown of a previous operational cycle;

enabling the start of the operational cycle; and

transitioning to the manager check state.

5. The operational cycle of claim 1, wherein the manager check state comprises:

checking the operational readiness of the constituent elements of the fuel processor;

transitioning to the preheat state.

6. The operational cycle of claim 1, wherein the manager check state comprises:

checking the operational readiness of the constituent elements of the fuel processor;

reporting an error detected during the check; and

transitioning to the shutdown state if the error is detected.

7. The operational cycle of claim 1, wherein the preheat state includes:

providing air, water, and the fuel to an oxidizer;

lighting off the oxidizer; and

purging a reactor of a reformer.

8. The operational cycle of claim 7, wherein the preheat state further includes transitioning to the startup state.

9. The operational cycle of claim 7, wherein the preheat state further includes:

detecting an error in the providing the air, water, and fuel, or in lighting of the oxidizer, or in purging the reactor; and

transitioning to the shutdown state.

10. The operational cycle of claim 1, wherein the startup state includes:

ramping production of a process feed stream; and

reforming the process feed stream as the production thereof builds.

11. The operational cycle of claim 1, wherein the startup state further includes transitioning the to run state.

12. The operational cycle of claim 10, wherein the startup state further includes:

detecting an error in ramping production of the process feed stream or in reforming the process feed stream; and

transitioning to the shutdown state.

13. The operational cycle of claim 1, wherein the run state includes:

generating a process feed stream;

reforming the process feed stream; and

transitioning to the shutdown state.

14. The operational cycle of claim 13, wherein the run state further includes detecting an error in generating the process feed stream or in reforming the process feed stream before transitioning to the shutdown state.

15. The operational cycle of claim 1, wherein the shutdown state includes:

purging an oxidizer and a reformer; and

cooling the purged oxidizer and reformer.

16. A fuel processor, comprising:

a supply of fuel, air and water;

an oxidizer receiving the fuel air and water and generating a process feed stream;

a reformer reforming the process feed stream into a hydrogen-rich gas; and

an automated control system directing the generation of the supply of fuel, air and water, generating the process feed stream, and reforming the process feed through an operational cycle, the operational cycle including;

an off state;

a manager check state entered into from the off state, and in which the operational readiness of the fuel processor is checked;

a preheat state entered into from the manager check state, and in which the fuel processor preheats gases, including the fuel, for mixing into a process feed stream;

a startup state entered into from the preheat state, and in which the fuel processor begins operating under start-up conditions;

a run state entered into from the startup state, and in which the fuel processor reforms the process feed stream into a reformate under steady-state conditions; and

a shutdown state entered into any one of the manager check state, preheat state, startup state, and run state.

17. The fuel processor of claim 16, wherein the operational cycle further comprises at least one of:

a manual state entered into from the off state, and into which an operator can direct operation of the overall system; and

an emergency shutdown state entered into from any one of the manager check state, the startup state, and the run state.

18. The fuel processor of claim 16, wherein the off state comprises at least two of:

displaying a message indicating the cause of the shutdown of a previous operational cycle;

enabling the start of the operational cycle;

transitioning to the manager check state; and

transitioning to the manual state.

19. The fuel processor of claim 16, wherein the off state comprises at least two of:

displaying a message indicating the cause of the shutdown of a previous operational cycle;

enabling the start of the operational cycle; and

transitioning to the manager check state.

20. The fuel processor of claim 16, wherein the manager check state comprises:

checking the operational readiness of the constituent elements of the fuel processor;

transitioning to the preheat state.

21. The fuel processor of claim 16, wherein the manager check state comprises:

checking the operational readiness of the constituent elements of the fuel processor;

reporting an error detected during the check; and

transitioning to the shutdown state if the error is detected.

22. The fuel processor of claim 16, wherein the preheat state includes:

providing air, water, and the fuel to an oxidizer;

lighting off the oxidizer; and

purging a reactor of a reformer.

23. The fuel processor of claim 22, wherein the preheat state further includes transitioning to the startup state.

24. The fuel processor of claim 22, wherein the preheat state further includes:

detecting an error in the providing the air, water, and fuel, or in lighting of the oxidizer, or in purging the reactor; and

transitioning to the shutdown state.

25. The fuel processor of claim 16, wherein the startup state includes:

ramping production of a process feed stream; and

reforming the process feed stream as the production thereof builds.

26. The fuel processor of claim 16, wherein the startup state further includes transitioning the to run state.

27. The fuel processor of claim 25, wherein the startup state further includes:

detecting an error in ramping production of the process feed stream or in reforming the process feed stream; and

transitioning to the shutdown state.

28. The fuel processor of claim 16, wherein the run state includes:

generating a process feed stream;

reforming the process feed stream; and

transitioning to the shutdown state.

29. The fuel processor of claim 28, wherein the run state further includes detecting an error in generating the process feed stream or in reforming the process feed stream before transitioning to the shutdown state.

30. The fuel processor of claim 16, wherein the shutdown state includes:

purging an oxidizer and a reformer; and

cooling the purged oxidizer and reformer.

31. The fuel processor of claim 16, wherein the supply of fuel, air and water comprises:

a fuel subsystem;

an air subsystem; and

a water subsystem.

32. The fuel processor of claim 16, wherein the oxidizer comprises an anode tailgas oxidizer.

33. The fuel processor of claim 16, wherein the reformer is an autothermal reformer.

34. A power plant, comprising:

a fuel processor, comprising;

a supply of fuel, air and water;

an oxidizer receiving the fuel air and water and generating a process feed stream;

a reformer reforming the process feed stream into a hydrogen-rich gas; and

an automated control system directing the generation of the supply of fuel, air and water, generating the process feed stream, and reforming the process feed through an operational cycle, the operational cycle including;

an off state;

a manager check state entered into from the off state, and in which the operational readiness of the fuel processor is checked;

a preheat state entered into from the manager check state, and in which the fuel processor preheats gases, including the fuel, for mixing into a process feed stream;

a startup state entered into from the preheat state, and in which the fuel processor begins operating under start-up conditions;

a run state entered into from the startup state, and in which the fuel processor reforms the process feed stream into a reformate under steady-state conditions; and

a shutdown state entered into any one of the manager check state, preheat state, startup state, and run state; and

a fuel cell receiving the hydrogen-rich gas.

35. The power plant of claim 34, wherein the operational cycle further comprises at least one of:

a manual state entered into from the off state, and into which an operator can direct operation of the overall system; and

an emergency shutdown state entered into from any one of the manager check state, the startup state, and the run state.

36. The power plant of claim 34, wherein the off state comprises at least two of:

displaying a message indicating the cause of the shutdown of a previous operational cycle;

enabling the start of the operational cycle;

transitioning to the manager check state; and

transitioning to the manual state.

37. The power plant of claim 34, wherein the off state comprises at least two of:

displaying a message indicating the cause of the shutdown of a previous operational cycle;

enabling the start of the operational cycle; and

transitioning to the manager check state.

38. The power plant of claim 34, wherein the manager check state comprises:

checking the operational readiness of the constituent elements of the fuel processor;

transitioning to the preheat state.

39. The power plant of claim 34, wherein the manager check state comprises:

checking the operational readiness of the constituent elements of the fuel processor;

reporting an error detected during the check; and

transitioning to the shutdown state if the error is detected.

40. The power plant of claim 34, wherein the preheat state includes:

providing air, water, and the fuel to an oxidizer;

lighting off the oxidizer; and

purging a reactor of a reformer.

41. The power plant of claim 40, wherein the preheat state further includes transitioning to the startup state.

42. The power plant of claim 40, wherein the preheat state further includes:

detecting an error in the providing the air, water, and fuel, or in lighting of the oxidizer, or in purging the reactor; and

transitioning to the shutdown state.

43. The power plant of claim 34, wherein the startup state includes:

ramping production of a process feed stream; and

reforming the process feed stream as the production thereof builds.

44. The power plant of claim 34, wherein the startup state further includes transitioning the to run state.

45. The power plant of claim 43, wherein the startup state further includes:

detecting an error in ramping production of the process feed stream or in reforming the process feed stream; and

transitioning to the shutdown state.

46. The power plant of claim 34, wherein the run state includes:

generating a process feed stream;

reforming the process feed stream; and

transitioning to the shutdown state.

47. The power plant of claim 46, wherein the run state further includes detecting an error in generating the process feed stream or in reforming the process feed stream before transitioning to the shutdown state.

48. The power plant of claim 34, wherein the shutdown state includes:

purging an oxidizer and a reformer; and

cooling the purged oxidizer and reformer.

49. The power plant of claim 34, wherein the supply of fuel, air and water comprises:

a fuel subsystem;

an air subsystem; and

a water subsystem.

50. The power plant of claim 34, wherein the oxidizer comprises an anode tailgas oxidizer.

51. The power plant of claim 34, wherein the reformer is an autothermal reformer.

52. The power plant of claim 34, wherein fuel cell comprises a proton exchange membrane fuel cell.

53. A method for operating a fuel processor, comprising:

transitioning from an off state to a manager check state in which the operational readiness of the fuel processor is checked;

transitioning from the manager check state to a preheat state in which the fuel processor preheats gases, including the fuel, for mixing into a process feed stream;

transitioning from the preheat state to a startup state in which the fuel processor begins operating under start-up conditions;

transitioning from the startup state to a run state in which the fuel processor reforms the process feed stream into a reformate under steady-state conditions; and

transitioning from any one of the manager check state, the preheat state, the startup sate, and the run state into a shutdown state.

54. The method of claim 53, further comprising at least one of:

transitioning to a manual state from the off state, and into which an operator can direct operation of the overall system; and

transitioning to an emergency shutdown state from any one of the manager check state, the startup state, and the run state.

55. The method of claim 53, wherein the off state comprises at least two of:

displaying a message indicating the cause of the shutdown of a previous operational cycle;

enabling the start of the operational cycle;

transitioning to the manager check state; and

transitioning to the manual state.

56. The method of claim 53, wherein the off state comprises at least two of:

displaying a message indicating the cause of the shutdown of a previous operational cycle;

enabling the start of the operational cycle; and

transitioning to the manager check state.

57. The method of claim 53, wherein the manager check state comprises:

checking the operational readiness of the constituent elements of the fuel processor;

transitioning to the preheat state.

58. The method of claim 53, wherein the manager check state comprises:

checking the operational readiness of the constituent elements of the-fuel processor;

reporting an error detected during the check; and

transitioning to the shutdown state if the error is detected.

59. The method of claim 53, wherein the preheat state includes:

providing air, water, and the fuel to an oxidizer;

lighting off the oxidizer; and

purging a reactor of a reformer.

60. The method of claim 59, wherein the preheat state further includes transitioning to the startup state.

61. The method of claim 59, wherein the preheat state further includes:

detecting an error in the providing the air, water, and fuel, or in lighting of the oxidizer, or in purging the reactor; and

transitioning to the shutdown state.

62. The method of claim 53, wherein the startup state includes:

ramping production of a process feed stream; and

reforming the process feed stream as the production thereof builds.

63. The method of claim 53, wherein the startup state further includes transitioning the to run state.

64. The method of claim 62, wherein the startup state further includes:

detecting an error in ramping production of the process feed stream or in reforming the process feed stream; and

transitioning to the shutdown state.

65. The method of claim 53, wherein the run state includes:

generating a process feed stream;

reforming the process feed stream; and

transitioning to the shutdown state.

66. The method of claim 65, wherein the run state further includes detecting an error in generating the process feed stream or in reforming the process feed stream before transitioning to the shutdown state.

67. The method of claim 53, wherein the shutdown state includes:

purging an oxidizer and a reformer; and

cooling the purged oxidizer and reformer.