Reformer-electrolyzer-purifier (REP) assembly for hydrogen production, systems incorporating same and method of producing hydrogen

Patent metadata

Field	Value
Publication number	US-10892507-B2
Application number	US-201515115186-A
Country	US
Kind code	B2
Filing date	Jan 30, 2015
Priority date	Jan 31, 2014
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

A high temperature electrolyzer assembly comprising at least one electrolyzer fuel cell including an anode and a cathode separated by an electrolyte matrix, and a power supply for applying a reverse voltage to the at least one electrolyzer fuel cell, wherein a gas feed comprising steam and one or more of CO2 and hydrocarbon fuel is fed to the anode of the at least one electrolyzer fuel cell, and wherein, when the power supply applies the reverse voltage to the at least one electrolyzer fuel cell, hydrogen-containing gas is generated by an electrolysis reaction in the anode of the at least one electrolyzer fuel cell and carbon dioxide is separated from the hydrogen-containing gas so that the at least one electrolyzer fuel cell outputs the hydrogen-containing gas and separately outputs an oxidant gas comprising carbon dioxide and oxygen.

First claim

We claim:

1. A high temperature reformer-electrolyzer-purifier (REP) assembly comprising:
one or more reformers configured to reform hydrocarbon fuel and output a gas feed comprising steam, and carbon-containing gas that includes CO 2 , H 2 , CO, and hydrocarbon fuel;
at least one fuel cell comprising an anode and a cathode separated by an electrolyte, wherein the anode of the at least one fuel cell is configured to receive the gas feed from the one or more reformers; and
a power supply configured to apply a reverse voltage to the at least one fuel cell,
wherein the at least one fuel cell is configured such that, when the power supply applies the reverse voltage to the at least one fuel cell, hydrogen-containing gas is generated in the anode of the at least one fuel cell by a hydrogen generation reaction, and carbon dioxide is separated from the hydrogen-containing gas by an electrolysis reaction in the anode of the at least one fuel cell such that the anode of the at least one fuel cell outputs the hydrogen-containing gas and the cathode of the at least one fuel cell separately outputs an oxidant gas comprising carbon dioxide and oxygen, and
wherein the power supply is configured to apply the reverse voltage so as to drive a hydrogen generation reaction to near completion by the separation and removal of the carbon dioxide from the hydrogen-containing gas.

2. The high temperature REP assembly in accordance with claim 1 , wherein the power supply is configured to apply the reverse voltage so that the hydrogen-containing gas output from the at least one fuel cell comprises 95% or greater hydrogen.

3. The high temperature REP assembly in accordance with claim 1 , wherein the at least one fuel cell is a molten carbonate fuel cell.

4. The high temperature REP assembly in accordance with claim 1 , wherein the at least one fuel cell is further adapted to perform one or more of:
reacting methane with water to produce hydrogen and carbon dioxide; and
shifting carbon monoxide with water to produce hydrogen and carbon dioxide.

5. The high temperature REP assembly in accordance with claim 1 , wherein:
the high temperature REP assembly is configured to operate in a hydrogen producing mode and a power producing mode, and
the high temperature REP assembly further comprises a controller configured to control the power supply to apply the reverse voltage to the at least one fuel cell when the high temperature REP assembly operates in the hydrogen producing mode such that the at least one fuel cell generates the hydrogen-containing gas, and the controller is configured to control the power supply not to apply the reverse voltage to the at least one fuel cell when the high temperature REP assembly operates in the power producing mode such that the at least one fuel cell generates power from fuel.

6. A reformer-electrolyzer-purifier (REP) system comprising:
the high temperature REP assembly in accordance with claim 1 ; and
a heater configured to heat the gas feed so as to vaporize water into steam prior to conveying the gas feed to the at least one fuel cell.

7. The REP system in accordance with claim 6 , further comprising a hydrogen purification assembly configured to receive the hydrogen-containing gas output from the high temperature REP assembly and to further purify the hydrogen in the hydrogen-containing gas.

8. A power production and hydrogen generation system comprising;
the high temperature REP assembly in accordance with claim 1 ; and
a high temperature fuel cell system, comprising at least one high temperature fuel cell stack;
wherein the high temperature fuel cell system is configured to receive fuel and one or more of air and the oxidant gas output from the high temperature REP assembly and to generate an electrical power output, and
wherein an anode side of the high temperature fuel cell system is configured to output anode exhaust, and the anode of the high temperature REP assembly is configured to receive said anode exhaust as the gas feed for generating the hydrogen-containing gas.

9. The power production and hydrogen generation system of claim 8 , wherein a cathode side of the high temperature fuel cell system is configured to receive the oxidant gas output from the high temperature REP assembly and to output cathode exhaust to a cathode of the high temperature REP assembly.

10. The power production and hydrogen generation system of claim 8 , wherein the power supply of the high temperature REP assembly is configured to use all or a portion of the electrical power output generated by the high temperature fuel cell system to apply the reverse voltage to the at least one fuel cell.

11. A hydrogen generation system for generating hydrogen and electrical power, the system comprising:
the high temperature REP assembly in accordance with claim 1 ; and
a low temperature fuel cell system configured to receive the hydrogen-containing gas output from the high temperature REP assembly and to generate electrical power.

12. The hydrogen generation system in accordance with claim 11 , wherein the low temperature fuel cell system comprises a PEM fuel cell system.

13. An energy storage system for storing excess power, the system comprising:
the high temperature REP assembly in accordance with claim 1 ; and
a fuel cell power producing assembly for generating power,
wherein a first portion of anode exhaust output from an anode side of the fuel cell power producing assembly is conveyed to the high temperature REP assembly for use as the gas feed, and
wherein when excess power is available, the power supply applies the reverse voltage to the at least one fuel cell of the high temperature REP assembly so as to generate hydrogen from the first portion of the anode exhaust.

Assignees

• Fuelcell Energy Inc

Inventors

• Jahnke Fred C
• Lambrech Matthew
• Patel Pinakin
• Farooque Mohammad
• Yuh Chao-Yi

Classifications

• Y02P20/129

  Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines · CPC title

• H01M2008/147

  Fuel cells with molten carbonates · CPC title

• H01M8/186 Primary

  by electrolytic decomposition of the electrolytic solution or the formed water product · CPC title

• H01M8/145

  comprising carbonates · CPC title

• H01M8/12

  operating at high temperature, e.g. with stabilised ZrO2 electrolyte · CPC title