System and method for removing water and hydrogen from anode exhaust

Patent metadata

Field	Value
Publication number	US-11201337-B2
Application number	US-201816229285-A
Country	US
Kind code	B2
Filing date	Dec 21, 2018
Priority date	Dec 21, 2018
Publication date	Dec 14, 2021
Grant date	Dec 14, 2021

Abstract

A fuel cell system includes an anode configured to output an anode exhaust stream comprising hydrogen, carbon dioxide, and water; and a membrane dryer configured to receive the anode exhaust stream, remove water from the anode exhaust stream, and output a membrane dryer outlet stream. The membrane dryer includes a first chamber configured to receive the anode exhaust stream; a second chamber configured to receive a purge gas; and a semi-permeable membrane separating the first chamber and the second chamber. The semi-permeable membrane is configured to allow water to diffuse therethrough, thereby removing water from the anode exhaust stream. The membrane dryer may further be configured to remove hydrogen from the anode exhaust stream.

First claim

What is claimed is:

1. A fuel cell system comprising:
an anode configured to output an anode exhaust stream comprising hydrogen, carbon dioxide, and water; and
a membrane dryer configured to receive the anode exhaust stream, remove water from the anode exhaust stream, and output a membrane dryer outlet stream, the membrane dryer comprising:
a first chamber configured to receive the anode exhaust stream and to output the membrane dryer output stream,
a second chamber configured to receive a purge gas having a lower concentration of water than the anode exhaust stream, and to output a process recycle stream, and
a semi-permeable membrane separating the first chamber and the second chamber,

wherein the semi-permeable membrane is configured to allow water and hydrogen to diffuse therethrough, thereby removing water and hydrogen from the anode exhaust stream;
wherein the membrane dryer is configured such that the process recycle stream output from the second chamber comprises the purge gas, hydrogen that diffused through the semi-permeable membrane, and water that diffused through the semi-permeable membrane.

2. The fuel cell system of claim 1 , further comprising a carbon dioxide liquefaction system configured to liquefy carbon dioxide in the membrane dryer outlet stream.

3. The fuel cell system of claim 2 , further comprising a liquid carbon dioxide separator configured to separate liquefied carbon dioxide from the membrane dryer outlet stream, thereby producing a carbon dioxide-lean off gas stream and a high purity liquid carbon dioxide stream.

4. The fuel cell system of claim 3 , further comprising a heat exchanger configured to heat the carbon dioxide-lean off gas stream and introduce the heated, carbon dioxide-lean off gas stream into the membrane dryer as the purge gas.

5. The fuel cell system of claim 2 , further comprising a heat exchanger configured to cool the anode exhaust stream to the membrane dryer to above the freezing temperature of water, with a system to remove liquid water and minimize the amount of water fed to the membrane dryer.

6. The fuel cell system of claim 1 , further comprising an anode gas compressor located downstream of the anode,
wherein the anode gas compressor is configured to compress the anode exhaust stream upstream of the membrane dryer.

7. The fuel cell system of claim 1 , further comprising at least one additional membrane dryer.

8. The fuel cell system of claim 7 , wherein the membrane dryer and the at least one additional membrane dryer are connected in parallel.

9. The fuel cell system of claim 7 , wherein the membrane dryer and the at least one additional membrane dryer are connected in series.

Assignees

• Fuelcell Energy Inc

Inventors

• Jolly Stephen
• Chimbole Jr Frank J
• Jahnke Fred C
• Malwitz Jonathan
• Ghezel-Ayagh Hossein

Classifications

• B01D53/268

  by diffusion · CPC title

• H01M8/04149 Primary

  by diffusion, e.g. making use of membranes · CPC title

• H01M8/04156

  with product water removal · CPC title

• H01M8/0687

  Reactant purification by the use of membranes or filters · CPC title

• B01D53/227

  in parallel connexion · CPC title