Carbonate fuel cell system with thermally integrated gasification

• US 5,554,453 A
• Filed: 01/04/1995
• Issued: 09/10/1996
• Est. Priority Date: 01/04/1995
• Status: Expired due to Term

• Current Assignee: Energy Research Corporation
• Original Assignee: Energy Research Corporation
• Inventors: Lee, Arthur, Meyers, Steven J., Steinfeld, George
• Primary Examiner(s): Kalafut, Stephen
• Assistant Examiner(s): CHANEY, CAROL DIANE
• Application Number:
  US08/368,430
• Time in Patent Office: 615 Days
• Field of Search: 429/17, 429/19, 429/16, 429/20, 429/26
• US Class Current: 429/415
• CPC Class Codes: H01M 2008/147 Fuel cells with molten carbonates
• CPC Class Codes: H01M 2300/0051 Carbonates
• CPC Class Codes: H01M 8/04022 Heating by combustion
• CPC Class Codes: H01M 8/0643 Gasification of solid fuel
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A fuel cell system employing a gasifier for generating fuel gas for the fuel cell of the fuel cell system and in which heat for the gasifier is derived from the anode exhaust gas of the fuel cell.

Claims

1. A fuel cell system comprising:

a fuel cell having an anode compartment and a cathode compartment for receiving fuel gas and oxidant gas, respectively;

a gasifier for generating fuel gas for said fuel cell;

and a catalytic burner means which receives the exhaust gas from said anode compartment of said fuel cell and which burns said anode exhaust gas and an oxidant gas to generate and directly transfer heat to gases generated by said gasifier without said exhaust gases admiring with the gases generated by said gasifier.

2. A fuel cell in accordance with claim 1, wherein:

said gasifier is one of a catalytic coal gasifier and a biomass gasifier.

3. A fuel cell system in accordance with claim 2 wherein:

said catalytic burner means comprises a catalytic burner disposed within said gasifier.

4. A fuel cell system in accordance with claim 3, wherein:

said fuel cell is a carbonate fuel cell.

5. A fuel cell system in accordance with claim 4, wherein:

said fuel cell is an internally reforming carbonate fuel cell.

6. A fuel cell system in accordance with claim 2, wherein:

said catalytic burner means is disposed externally of said gasifier.

7. A fuel cell system in accordance with claim 6 further comprising:

a recycle loop external of said gasifier for recycling a portion of the output gas of said gasifier back to the input of said gasifier;

and said catalytic burner means includes a catalytic burner and a heat exchanger in communication with said catalytic burner which transfer said heat to said recycled portion of said output gas of said gasifier.

8. A fuel cell system in accordance with claim 7, wherein said recycled portion of the output gas of said gasifier is between 80 to 90 percent of said output gas of said gasifier.

9. A fuel cell system in accordance with claim 7, wherein:

said fuel cell is a carbonate fuel cell.

10. A fuel cell system in accordance with claim 9, wherein:

said fuel cell is an internally reforming carbonate fuel cell.

11. A fuel cell system in accordance with claim 6, wherein:

said fuel cell is a carbonate fuel cell.

12. A fuel cell system in accordance with claim 11, wherein:

said fuel cell is an internally reforming carbonate fuel cell.

13. A fuel cell system in accordance with claim 2, wherein:

said gasifier is operated at low temperature and high pressure.

14. A fuel cell system in accordance with claim 13, wherein:

said catalytic burner is operated at high temperature and low pressure.

15. A fuel cell system in accordance with claim 14, wherein:

said gasifier is operated at a temperature in the range of 1200°

to 1400°

F. and a pressure in the range of 300 to 700 psig;

and said catalytic burner is operated at a temperature in the range of 1600°

-1800°

F. and a pressure in the range of 0 to 15 psig.

16. A fuel cell system in accordance with claim 14, wherein:

said fuel cell is a carbonate fuel cell.

17. A fuel cell system in accordance with claim 16, wherein:

said fuel cell is an internally reforming carbonate fuel cell.

18. A fuel cell system in accordance with claim 13, wherein:

the operating temperature of said gasifier differs from the operating temperature of said fuel cell by less than 200°

F.

19. A fuel cell system in accordance with claim 13, wherein:

said fuel cell is a carbonate fuel cell.

20. A fuel cell system in accordance with claim 19, wherein:

said fuel cell is an internally reforming carbonate fuel cell.

21. A method for generating fuel gas to be received in the anode compartment of a fuel cell whose cathode compartment is to receive oxidant gas, the method comprising:

gasifying a material to generate fuel gas for said anode compartment of said fuel cell; and

catalytically burning the exhaust gas from the anode compartment of said fuel cell with an oxidant gas to generate heat and directly transferring said heat to said gasification step without said anode exhaust gas admixing with the gases generated in said gasification step.

22. A method in accordance with claim 21, wherein:

said gasification step includes one of catalytic coal gasification and biomass gasification.

23. A method in accordance with claim 22, wherein:

said catalytic burning occurs within the gasifier in which said gasification occurs.

24. A method in accordance with claim 23, wherein:

said fuel cell is a carbonate fuel cell.

25. A method in accordance with claim 24, wherein

said fuel cell is an internally reforming carbonate fuel cell.

26. A method in accordance with claim 22, wherein:

said catalytic burning occurs external to the gasifier in which said gasification occurs.

27. A method in accordance with claim 26, further comprising:

recycling a portion of the gas generated in said gasification step back to said gasification step;

and said step of transferring and generating said heat includes transferring said heat to said recycled portion of said gas generated in said gasification step.

28. A method in accordance with claim 27, wherein:

said recycled portion of the gas generated in said gasification step is in the range of 80 to 90 percent of said gas.

29. A method in accordance with claim 27, wherein:

said fuel cell is a carbonate fuel cell.

30. A method in accordance with claim 29, wherein:

said fuel cell is an internally reforming carbonate fuel cell.

31. A method in accordance with claim 26, wherein:

said fuel cell is a carbonate fuel cell.

32. A method in accordance with claim 31, wherein:

said fuel cell is an internally reforming carbonate fuel cell.

33. A method in accordance with claim 22, wherein:

said gasification step is conducted at low temperature and high pressure.

34. A method in accordance with claim 33, wherein:

said catalytic burning step is conducted at high temperature and low pressure.

35. A method in accordance with claim 34, wherein:

said gasification step is carried out at a temperature in the range of 1200°

to 1400°

F. and a pressure in the range of 300-700 psig;

and said catalytic burning step is carried out at a temperature in the range of 1600°

to 1800°

F. and a pressure in the range of 0-15 psig.

36. A method in accordance with claim 34, wherein:

said fuel cell is a carbonate fuel cell.

37. A method in accordance with claim 36, wherein:

said fuel cell is an internally reforming molten carbonate fuel cell.

38. A fuel cell system in accordance with claim 21, wherein:

the operating temperature of said gasification step differs from the operating temperature of said fuel cell by less than 200°

F.

39. A method in accordance with claim 21, wherein:

said fuel cell is a carbonate fuel cell.

40. A method in accordance with claim 39, wherein:

said fuel cell is an internally reforming carbonate fuel cell.

41. Apparatus for use in a fuel cell system including a fuel cell having an anode compartment and a cathode compartment for receiving fuel gas and oxidant gas, respectively, said apparatus comprising:

a gasifier for generating fuel gas for said fuel cell;

and a catalytic burner disposed within said gasifier, said catalytic burner receiving exhaust gas from said anode compartment of said fuel cell burning said anode exhaust gas and an oxidant gas to generate and directed transfer heat to gases generated by said gasifier without said anode exhaust gas admixing with the gases generated by said gasifier.

42. An apparatus in accordance with claim 41, wherein

said gasifier is one of a catalytic coal gasifier and a biomass gasifier.

43. Apparatus in accordance with claim 42, wherein:

said fuel cell is a carbonate fuel cell.

44. Apparatus in accordance with claim 43, wherein:

said fuel cell is an internally reforming carbonate fuel cell.