Hydrogen generation using a fuel cell system with an REP

Patent metadata

Field	Value
Publication number	US-11710836-B2
Application number	US-202016878112-A
Country	US
Kind code	B2
Filing date	May 19, 2020
Priority date	Nov 22, 2017
Publication date	Jul 25, 2023
Grant date	Jul 25, 2023

Abstract

A fuel cell system includes a fuel cell having an anode and a cathode configured to output cathode exhaust. The fuel cell is configured to generate waste heat. The fuel cell system further includes a reformer configured to partially reform a feed gas using the waste heat and output a hydrogen-containing stream. The fuel cell system further includes a reformer-electrolyzer-purifier (“REP”) having an REP anode configured to receive a first portion of the hydrogen-containing stream and an REP cathode.

First claim

What is claimed is:

1. A fuel cell system comprising:
a fuel cell comprising:
an anode; and
a cathode configured to output cathode exhaust; and
wherein the fuel cell is configured to generate waste heat;

a reformer configured to partially reform a feed gas using the waste heat and output a hydrogen-containing stream; and
a reformer-electrolyzer-purifier (“REP”) comprising:
an REP anode configured to receive a first portion of the hydrogen-containing stream; and
an REP cathode;

an anode gas oxidizer (“AGO”) configured to receive anode exhaust from the anode;
wherein the AGO is configured to oxidize the anode exhaust with air from an air supply; and
wherein the AGO is configured to receive heated sweep gas from the REP cathode.

2. The fuel cell system of claim 1 , further comprising:
a heat exchanger configured to heat the feed gas using the waste heat and to output a heated feed gas;
wherein the waste heat is conveyed to the heat exchanger in the cathode exhaust; and
wherein the reformer is configured to receive the heated feed gas.

3. The fuel cell system of claim 1 , wherein the fuel cell is configured to receive a remaining portion of the hydrogen-containing stream.

4. The fuel cell system of claim 1 , further comprising:
an indirect reforming unit disposed on the anode;
wherein the indirect reforming unit is configured to further reform the hydrogen-containing stream and output a fuel turn gas.

5. The fuel cell system of claim 4 , wherein:
a first portion of the fuel turn gas is the first portion of the hydrogen-containing stream received by the REP anode; and
the anode is configured to receive a remaining portion of the fuel turn gas.

6. The fuel cell system of claim 4 , wherein the REP anode is configured to receive a portion of anode exhaust output from the anode.

7. The fuel cell system of claim 4 , wherein the anode is configured to receive a remaining portion of the fuel turn gas output from the indirect reforming unit.

8. The fuel cell system of claim 4 , further comprising:
a heat transfer element disposed in the AGO;
wherein the fuel cell system is configured to mix a first portion of the fuel turn gas with water from a water supply to form a hydrated feed gas;
wherein the heat transfer element is configured to receive the hydrated feed gas and transfer heat from an oxidation reaction in the AGO to the hydrated feed gas; and
wherein the REP anode is configured to receive the hydrated feed gas from the heat transfer element.

9. The fuel cell system of claim 1 , further comprising:
a heat transfer element disposed in the AGO;
wherein the fuel cell system is configured to mix the first portion of the hydrogen-containing stream with water from a water supply to form a hydrated feed gas; and
wherein the heat transfer element is configured to receive the hydrated feed gas and to transfer heat from an oxidation reaction in the AGO to the hydrated feed gas.

10. The fuel cell system of claim 9 , wherein the REP anode is configured to receive the hydrated feed gas from the heat transfer element.

11. The fuel cell system of claim 1 , further comprising a heat transfer element disposed in the AGO and configured to receive air from the air supply and transfer heat from an oxidation reaction in the AGO to the air passing through the heat transfer element.

12. A method of operating a fuel cell system comprising:
providing a fuel cell having an anode and a cathode;
providing a reformer;
providing an REP having an REP anode and an REP cathode;
generating waste heat from the fuel cell;
heating feed gas with the waste heat, forming heated feed gas;
partially reforming the heated feed gas in the reformer and outputting a hydrogen-containing stream;
hydrating a first portion of the hydrogen-containing stream with steam from a water supply to form a hydrated feed gas;
reforming the hydrated feed gas and outputting a reformed hydrated feed gas;
feeding the reformed hydrated feed gas to the REP anode;
feeding a remaining portion of the hydrogen-containing stream to the anode; and
outputting anode exhaust from the anode.

13. The method of claim 12 , further comprising mixing a portion of the anode exhaust with the hydrated feed gas prior to introduction to the REP anode.

14. A fuel cell system comprising:
a feed system comprising:
a water supply; and
a fuel supply;
wherein the feed system is configured to purify water from the water supply and fuel from the fuel supply; and
wherein the feed system is configured to mix the water and fuel to form a hydrated feed gas;

a fuel cell comprising:
an anode configured to receive a first portion of the hydrated feed gas; and
a cathode; and

a reformer-electrolyzer-purifier (“REP”) comprising:
an REP anode configured to receive a second portion of the hydrated feed gas; and
an REP cathode;

at least one of a hydrogen purification device or a hydrogen pressurization device configured to recycle at least a portion of hydrogen output from the REP anode to the feed system;
wherein the fuel cell system is configured to mix at least a portion of hydrogen output from the REP anode with the hydrated feed gas.

15. The system of claim 14 , further comprising a water treatment system configured to purify the water from the water supply.

16. The system of claim 14 , further comprising a first heat exchanger configured to receive the hydrated feed gas and to vaporize at least a portion of the water in the hydrated feed gas.

17. The system of claim 16 , further comprising a second heat exchanger configured to receive the hydrated feed gas and to vaporize the water in the hydrated feed gas remaining after passing through the first heat exchanger.

18. The system of claim 14 , further comprising a reformer configured to reform a portion of the hydrated feed gas to hydrogen.

Assignees

• Fuelcell Energy Inc

Inventors

• Jahnke Fred C
• Lambrech Matthew

Classifications

• C25B9/73

  of the filter-press type · CPC title

• H01M8/04014 Primary

  Heat exchange using gaseous fluids; Heat exchange by combustion of reactants · CPC title

• C25B1/04

  by electrolysis of water · CPC title

• C25B15/08

  Supplying or removing reactants or electrolytes; Regeneration of electrolytes · CPC title

• H01M8/04126

  Humidifying · CPC title