Hybrid reformer for fuel flexibility

• US 8,057,944 B2
• Filed: 04/22/2010
• Issued: 11/15/2011
• Est. Priority Date: 04/03/2006
• Status: Active Grant

• Current Assignee: Bloom Energy Corporation
• Original Assignee: Bloom Energy Corporation
• Inventors: Venkataraman, Swaminathan
• Primary Examiner(s): Kalafut; Stephen J.
• Application Number:
  US12/765,213
• Publication Number:
  US 20100203416A1
• Time in Patent Office: 572 Days
• Field of Search: 429/416, 429/423, 422/190, 422/191, 422/625, 422/634, 422/639, 422/644
• US Class Current: 429/429
• CPC Class Codes: C01B 2203/0227 containing a catalytic reforming step
• CPC Class Codes: C01B 2203/066 with fuel cells
• CPC Class Codes: C01B 2203/0811 by combustion of fuel
• CPC Class Codes: C01B 2203/1052 Nickel or cobalt catalysts
• CPC Class Codes: C01B 2203/107 Platinum catalysts
• CPC Class Codes: C01B 2203/1205 Composition of the feed
• CPC Class Codes: C01B 2203/1235 Hydrocarbons
• CPC Class Codes: C01B 2203/142 At least two reforming, decomposition or partial oxidation steps in series
• CPC Class Codes: C01B 3/382 Multi-step processes
• CPC Class Codes: H01M 2008/1293 Fuel cells with solid oxide electrolytes
• CPC Class Codes: H01M 8/0247 characterised by the form characterised by a channel configuration H01M8/0258
• 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 8/0625 in a modular combined reactor/fuel cell structure
• CPC Class Codes: H01M 8/0631 Reactor construction specially adapted for combination reactor/fuel cell hydrogen C01B3/00; reactors for physicochemical processes B01J19/00
• CPC Class Codes: H01M 8/0662 Treatment of gaseous reactants or gaseous residues, e.g. cleaning
• CPC Class Codes: H01M 8/2425 High-temperature cells with solid electrolytes
• CPC Class Codes: H01M 8/2465 Details of groupings of fuel cells
• CPC Class Codes: H01M 8/2475 Enclosures, casings or containers of fuel cell stacks
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 20/52 : using catalysts, e.g. selective catalysts

Abstract

A reformer for a fuel cell system includes a leading segment and a trailing segment. The leading segment includes less reactive catalyst and/or more stabilizing catalyst than the trailing segment. The reformer may be used for reformation of high and low hydrocarbon fuels.

Claims

1. A fuel cell system, comprising:

a high temperature fuel cell stack;

a reformer which comprises a leading segment and a trailing segment, wherein the leading segment comprises less reactive catalyst than the trailing segment, and wherein the leading segment and the trailing segment are located in a same reformer housing, and wherein the reactive catalyst comprises nickel; and

wherein the reformer housing is external to the high temperature fuel cell stack.

2. The fuel cell system of claim 1, wherein the leading segment contains a lower amount of nickel than the trailing segment.

3. The fuel cell system of claim 1, wherein the leading segment contains a lower nickel concentration than the trailing segment.

4. The fuel cell system of claim 1, wherein nickel amount or concentration increases between the leading segment and the trailing segment in a single step or in a graded fashion.

5. The fuel cell system of claim 1, wherein:

a rhodium stabilizing catalyst is located in the reformer; and

the leading segment of the reformer comprises more of the rhodium stabilizing catalyst than the trailing segment.

6. The fuel cell system of claim 1, wherein:

the at least one fuel cell stack comprises an internal or an external reformation type solid oxide fuel cells;

the reformer comprises an external reformer; and

the reformer is thermally integrated with the at least one fuel cell stack.

7. The fuel cell system of claim 6, further comprising a burner which is thermally integrated with the reformer.

8. The fuel cell system of claim 1, wherein the fuel cell stack comprises a solid oxide fuel cell stack.

9. A fuel cell system, comprising:

a high temperature fuel cell stack;

a reformer which comprises a leading segment and a trailing segment;

wherein;

the leading segment comprises more stabilizing catalyst than the trailing segment;

the leading segment comprises not more reactive catalyst than the trailing segment;

the reactive catalyst comprises nickel and the stabilizing catalyst comprises rhodium;

and

the leading segment and the trailing segment are located in a same reformer housing;

and

wherein the reformer housing is external to the high temperature fuel cell stack.

10. The fuel cell system of claim 9, wherein:

the leading segment of the reformer comprises a higher amount or concentration of the rhodium catalyst than the trailing segment; and

the leading segment of the reformer comprises a lower amount or concentration of the nickel catalyst than the trailing segment.

11. The fuel cell system of claim 9, wherein:

the leading segment of the reformer comprises a higher amount or concentration of the rhodium catalyst than the trailing segment; and

the leading segment of the reformer comprises a substantially equal amount or concentration of the nickel catalyst as the trailing segment.

12. The fuel cell system of claim 9, wherein the fuel cell stack comprises a solid oxide fuel cell stack.