High Temperature Fuel Cell System and Method of Operating the Same

• US 20110189567A1
• Filed: 02/03/2011
• Published: 08/04/2011
• Est. Priority Date: 01/22/2004
• Status: Abandoned Application

• Current Assignee: Bloom Energy Corporation
• Original Assignee: Bloom Energy Corporation
• Inventors: Gottmann, Matthias, Finn, John, Venkataraman, Swaminathan
• Application Number:
  US13/020,598
• Publication Number:
  US 20110189567A1
• Time in Patent Office: Days
• US Class Current: 429/425
• CPC Class Codes: B01J 19/249 Plate-type reactors
• CPC Class Codes: B01J 2208/00309 with two or more reactions in heat exchange with each other, such as an endothermic reaction in heat exchange with an exothermic reaction
• CPC Class Codes: B01J 2208/00716 Means for reactor start-up
• CPC Class Codes: B01J 2219/00006 Large-scale industrial plants
• CPC Class Codes: B01J 2219/2465 Two reactions in indirect heat exchange with each other
• CPC Class Codes: B01J 2219/2479 Catalysts coated on the surface of plates or inserts
• CPC Class Codes: B01J 2219/2481 Catalysts in granular from between plates
• CPC Class Codes: B01J 8/0257 in a cylindrical annular shaped bed
• CPC Class Codes: B01J 8/0285 Heating or cooling the reactor for tubular reactors in furnaces B01J8/062
• CPC Class Codes: C01B 2203/0233 the reforming step being a steam reforming step
• CPC Class Codes: C01B 2203/0283 containing a CO-shift step, i.e. a water gas shift step
• CPC Class Codes: C01B 2203/043 Regenerative adsorption process in two or more beds, one for adsorption, the other for regeneration
• CPC Class Codes: C01B 2203/0475 the impurity being carbon dioxide
• CPC Class Codes: C01B 2203/0495 the impurity being water
• CPC Class Codes: C01B 2203/066 with fuel cells
• CPC Class Codes: C01B 2203/0811 by combustion of fuel
• CPC Class Codes: C01B 2203/0822 the fuel containing hydrogen
• CPC Class Codes: C01B 2203/1035 Catalyst coated on equipment surfaces, e.g. reactor walls
• CPC Class Codes: C01B 2203/1241 Natural gas or methane
• CPC Class Codes: C01B 2203/127 Catalytic desulfurisation
• CPC Class Codes: C01B 2203/1294 : Evaporation by heat exchange with hot process stream
• CPC Class Codes: C01B 3/384 : the catalyst being continuously externally heated
• CPC Class Codes: C01B 3/48 : followed by reaction of water vapour with carbon monoxide
• CPC Class Codes: C01B 3/56 : by contacting with solids; Regeneration of used solids C01B3/508 takes precedence
• CPC Class Codes: H01M 2008/1293 : Fuel cells with solid oxide electrolytes
• CPC Class Codes: H01M 8/04007 : related to heat exchange
• CPC Class Codes: H01M 8/04022 : Heating by combustion
• CPC Class Codes: H01M 8/04097 : with recycling of the reactants H01M8/04119, H01M8/04104 take precedence
• CPC Class Codes: H01M 8/04164 : by condensers, gas-liquid separators or filters
• CPC Class Codes: H01M 8/04268 : Heating of fuel cells during the start-up of the fuel cells
• CPC Class Codes: H01M 8/0612 : from carbon-containing material
• CPC Class Codes: H01M 8/0625 : in a modular combined reactor/fuel cell structure
• CPC Class Codes: H01M 8/0668 : Removal of carbon monoxide or carbon dioxide
• CPC Class Codes: H01M 8/0675 : Removal of sulfur
• CPC Class Codes: H01M 8/12 : operating at high temperature, e.g. with stabilised ZrO2 electrolyte
• CPC Class Codes: H01M 8/18 : Regenerative fuel cells, e.g. redox flow batteries or secondary fuel cells
• CPC Class Codes: H01M 8/2432 : Grouping of unit cells of planar configuration
• CPC Class Codes: H01M 8/249 : comprising two or more groupings of fuel cells, e.g. modular assemblies
• CPC Class Codes: Y02E 60/50 : Fuel cells
• CPC Class Codes: Y02P 20/10 : Process efficiency
• CPC Class Codes: Y02P 20/129 : Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines

Abstract

A high temperature fuel cell stack system, such as a solid oxide fuel cell system, with an improved balance of plant efficiency includes a thermally integrated reformer, combustor and the fuel cell stack.

Claims

1. A method of operating a solid oxide fuel cell system, comprising:

operating the fuel cell system in a start-up mode by;

providing a hydrocarbon fuel and air into a catalytic partial oxidation reactor;

generating hydrogen in the catalytic partial oxidation reactor;

providing the generated hydrogen into a solid oxide fuel cell stack; and

stopping the generation of hydrogen in the catalytic partial oxidation reactor once the fuel cell stack reaches a predetermined operating temperature; and

operating the fuel cell system in a steady state operating mode to generate electricity after the fuel cell stack reaches a predetermined operating temperature.

2. The method of claim 1, wherein the predetermined operating temperature is a temperature at which oxidation of anode electrodes of solid oxide fuel cells in the solid oxide fuel cell stack is avoided.

3. The method of claim 1, further comprising heating the catalytic partial oxidation reactor during the start-up mode.

4. The method of claim 1, further comprising mixing the hydrocarbon fuel and air and providing the mixed hydrocarbon fuel and air into the catalytic partial oxidation reactor.

5. The method of claim 1, wherein the hydrocarbon fuel comprises methane or methane containing natural gas.

6. The method of claim 1, wherein the generated hydrogen is provided in the start-up mode from the catalytic partial oxidation reactor into the solid oxide fuel cell stack through a reformer.

7. The method of claim 6, wherein the generated hydrogen is provided in the start-up mode from the solid oxide fuel cell stack into a fuel heat exchanger.

8. The method of claim 7, wherein the generated hydrogen is provided in the start-up mode from the fuel heat exchanger into a combustor.

9. The method of claim 1, wherein the step of stopping the generation of hydrogen in the catalytic partial oxidation reactor comprises stopping operation of the catalytic partial oxidation reactor.

10. The method of claim 1, wherein operating the fuel cell system in a steady state operating mode comprises:

providing the hydrocarbon fuel and water vapor into a reformer;

reforming the hydrocarbon fuel in the reformer to form a hydrogen containing reaction product; and

providing the reaction product and air into the solid oxide fuel cell stack during the steady state operating mode of the stack.

11. The method of claim 10, wherein operating the fuel cell system in a steady state operating mode further comprises:

providing the hydrocarbon fuel into a fuel heat exchanger;

providing the hydrocarbon fuel from the fuel exchanger into the reformer;

providing the air into an air heat exchanger; and

providing the air from the air heat exchanger into the solid oxide fuel cell stack.

12. The method of claim 11, wherein operating the fuel cell system in a steady state operating mode further comprises:

providing an anode exhaust from the solid oxide fuel cell stack into the fuel heat exchanger to heat the hydrocarbon fuel;

providing at least a portion of the anode exhaust from the fuel heat exchanger into a combustor;

providing a cathode exhaust from the solid oxide fuel cell stack into the combustor; and

providing a combustor exhaust into the air heat exchanger to heat the air.

13. The method of claim 1, wherein operating the fuel cell system in a start-up mode further comprises:

providing the generated hydrogen from the catalytic partial oxidation reactor a reformer;

providing the generated hydrogen from the reformer into the solid oxide fuel cell stack;

providing the generated hydrogen from the solid oxide fuel cell stack into a fuel heat exchanger; and

providing the generated hydrogen from the fuel heat exchanger into a combustor.

14. The method of claim 13, wherein operating the fuel cell system in a steady state operating mode comprises:

providing the hydrocarbon fuel into a fuel heat exchanger;

providing the hydrocarbon fuel from the fuel exchanger into the reformer;

providing water vapor into the reformer;

reforming the hydrocarbon fuel in the reformer to form a hydrogen containing reaction product;

providing the reaction product into the solid oxide fuel cell stack;

providing the air into an air heat exchanger;

providing the air from the air heat exchanger into the solid oxide fuel cell stack;

providing an anode exhaust from the solid oxide fuel cell stack into the fuel heat exchanger to heat the hydrocarbon fuel;

providing at least a portion of the anode exhaust from the fuel heat exchanger into a combustor;

providing a cathode exhaust from the solid oxide fuel cell stack into the combustor; and

providing a combustor exhaust into the air heat exchanger to heat the air.