Steam methane reforming unit for carbon capture

Patent metadata

Field	Value
Publication number	US-2021284530-A1
Application number	US-202117194597-A
Country	US
Kind code	A1
Filing date	Mar 8, 2021
Priority date	Mar 11, 2020
Publication date	Sep 16, 2021
Grant date	—

Abstract

A molten carbonate fuel cell-powered system for capturing carbon dioxide produced by a steam methane reformer system. Tail gas from a pressure swing adsorption system is mixed with exhaust gas from the fuel cell anode, then pressurized and cooled to extract liquefied carbon dioxide. The residual low-CO 2 gas is directed to an anode gas oxidizer, to the anode, to the reformer to be burned for fuel, and/or to the pressure swing adsorption system. Low-CO 2 flue gas from the reformer can be vented to the atmosphere or directed to the anode gas oxidizer. Reduction in the amount of CO 2 reaching the fuel cell allows the fuel cell to be sized according to the power demands of the system and eliminates the need to export additional power output.

First claim

What is claimed is:

1 . A system for capturing carbon dioxide from a steam methane reformer system, the system for capturing carbon dioxide comprising:
a molten carbonate fuel cell comprising an anode and a cathode; a compressor configured to compress a gas mixture, the gas mixture comprising exhaust gas from the anode and tail gas from the steam methane reformer system; a chiller configured to cool the gas mixture; and a carbon dioxide separator configured to separate the gas mixture into liquefied carbon dioxide and a residual gas mixture.

2 . The system of claim 1 , further comprising:
an anode gas oxidizer; wherein a first portion of the residual gas mixture is directed from the carbon dioxide separator to the anode of the molten carbonate fuel cell and a second portion of the residual gas mixture is directed to the anode gas oxidizer.

3 . The system of claim 2 , wherein a third portion of the residual gas mixture is directed from the carbon dioxide separator to the steam methane reformer system to be burned as fuel.

4 . The system of claim 2 , wherein a third portion of the residual gas mixture is directed from the carbon dioxide separator to a pressure swing adsorption system in the steam methane reformer system.

5 . The system of claim 3 , wherein a fourth portion of the residual gas mixture is directed from the carbon dioxide separator to a pressure swing adsorption system in the steam methane reformer system.

6 . The system of claim 1 , wherein flue gas from a reformer in the steam methane reformer system is vented to the atmosphere.

7 . The system of claim 2 , wherein flue gas from a reformer in the steam methane reformer system is directed to the anode gas oxidizer.

8 . The system of claim 7 , wherein a third portion of the residual gas mixture is directed to a second pressure swing adsorption system outside the steam methane reformer system.

9 . The system of claim 3 , wherein the molten carbonate fuel cell is sized to power at least one of the system for capturing carbon dioxide or the steam methane reformer system.

10 . The system of claim 1 , wherein the steam methane reformer system comprises a pressure swing adsorption system configured to produce the tail gas.

11 . The system of claim 4 , wherein flue gas from a reformer in the steam methane reformer system is directed to the anode gas oxidizer.

12 . A system for capturing carbon dioxide from a steam methane reformer system, the system for capturing carbon dioxide comprising:
a compressor configured to compress tail gas from the steam methane reformer system; a chiller configured to cool the tail gas; and a carbon dioxide separator configured to separate the tail gas into liquefied carbon dioxide and residual tail gas.

13 . The system of claim 12 , wherein the residual tail gas is directed to the steam methane reformer system to be burned as fuel.

14 . The system of claim 12 , wherein the residual tail gas is directed to a pressure swing adsorption system in the steam methane reformer system.

15 . The system of claim 12 , wherein a first portion of the residual tail gas is directed to a pressure swing adsorption system in the steam methane reformer system and a second portion of the residual tail gas is directed to the steam methane reformer system to be burned as fuel.

16 . A method of capturing carbon dioxide from a steam methane reformer system, the method comprising:
mixing tail gas from the steam methane reformer system with anode exhaust gas from an anode of a molten carbonate fuel cell to form a gas mixture; compressing the gas mixture; cooling the gas mixture; and separating the gas mixture into liquid carbon dioxide and a residual gas mixture.

17 . The method of claim 16 , further comprising:
directing a first portion of the residual gas mixture to an anode gas oxidizer; and directing a second portion of the residual gas mixture to the anode of the molten carbonate fuel cell.

18 . The method of claim 17 , further comprising:
directing a third portion of the residual gas mixture to the steam methane reformer system to be burned as fuel.

19 . The method of claim 17 , further comprising:
directing a third portion of the residual gas mixture to a pressure swing adsorption system in the steam methane reformer system.

20 . The method of claim 18 , further comprising:
directing a fourth portion of the residual gas mixture to a pressure swing adsorption system in the steam methane reformer system.

Assignees

• Fuelcell Energy Inc

Inventors

• Jahnke Fred C
• Jolly Stephen
• Ghezel-Ayagh Hossein

Classifications

• Y02C20/40

  of CO2 · CPC title

• H01M16/003

  of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers · CPC title

• H01M8/0656

  by electrochemical means (H01M8/065 takes precedence) · CPC title

• H01M8/04007

  related to heat exchange · CPC title

• H01M8/0668

  Removal of carbon monoxide or carbon dioxide · CPC title