Methane generation system

Patent metadata

Field	Value
Publication number	US-2025323299-A1
Application number	US-202218867819-A
Country	US
Kind code	A1
Filing date	May 31, 2022
Priority date	May 31, 2022
Publication date	Oct 16, 2025
Grant date	—

Abstract

The methane generation system according to the present disclosure includes a methane generation unit including an electrolysis device that electrolyzes water to obtain hydrogen and a methane reactor that obtains a fuel gas containing methane by a methanation reaction using the hydrogen; a reformer that reforms the fuel gas to obtain a reformed gas; a fuel cell that generates electricity by a reaction of obtaining a product gas from the reformed gas and an oxygen-containing gas; a recovery device that separates a recovery gas containing carbon dioxide from return fluid which is a pail of the product gas; and a circulation path through which the recovery gas is guided to the methane generation unit.

First claim

What is claimed is:

1 . A methane generation system comprising:
a methane generation unit including an electrolysis device that electrolyzes water to obtain hydrogen and a methane reactor that obtains a fuel gas containing methane by a methanation reaction using the hydrogen; a reformer that reforms the fuel gas to obtain a reformed gas; a fuel cell that generates electricity by a reaction of obtaining a product gas from the reformed gas and an oxygen-containing gas; a recovery device that separates a recovery gas containing carbon dioxide from return fluid which is a part of the product gas; and a circulation path through which the recovery gas is guided to the methane generation unit.

2 . The methane generation system according to claim 1 ,
wherein the electrolysis device is a co-electrolysis device that obtains the hydrogen and carbon monoxide from the water and carbon dioxide by electrolysis.

3 . The methane generation system according to claim 1 , further comprising:
a return path through which a part of the product gas is guided to the reformer.

4 . The methane generation system according to claim 1 , further comprising:
an auxiliary supply path through which an auxiliary gas containing carbon dioxide is supplied to the recovery device.

5 . The methane generation system according to claim 1 ,
wherein a concentrator that increases concentration of carbon dioxide contained in a gas flowing through the circulation path is provided in the circulation path.

6 . The methane generation system according to claim 1 , further comprising:
an auxiliary supply path through which an auxiliary gas containing carbon dioxide is supplied to the circulation path; and an auxiliary concentrator that increases concentration of the carbon dioxide contained in the auxiliary gas.

7 . The methane generation system according to claim 5 , further comprising:
an auxiliary supply path through which an auxiliary gas containing carbon dioxide is supplied to the methane generation unit; and an auxiliary concentrator that increases concentration of the carbon dioxide contained in the auxiliary gas.

8 . The methane generation system according to claim 4 ,
wherein the auxiliary supply path that supplies indoor air as the auxiliary gas.

9 . The methane generation system according to claim 1 ,
wherein the recovery device that obtains the recovery gas by adjusting a temperature with a heat exchanger of an air conditioner.

10 .- 11 . (canceled)

12 . The methane generation system according to claim 1 ,
wherein the oxygen-containing gas contains oxygen obtained by electrolyzing the water in the electrolysis device.

13 . A methane generation system comprising:
a methane generation unit including a methane reactor that obtains a fuel gas containing methane by a methanation reaction using the hydrogen; a reformer that reforms the fuel gas to obtain a reformed gas; a fuel cell that generates electricity by a reaction of obtaining a product gas from the reformed gas and an oxygen-containing gas; a recovery device that separates a recovery gas containing carbon dioxide from return fluid which is a part of the product gas; and a circulation path through which the recovery gas is guided to the methane generation unit.

14 . The methane generation system according to claim 13 , further comprising:
a return path through which a part of the product gas is guided to the reformer.

15 . The methane generation system according to claim 13 , further comprising:
an auxiliary supply path through which an auxiliary gas containing carbon dioxide is supplied to the recovery device.

16 . The methane generation system according to claim 13 ,
wherein a concentrator that increases concentration of carbon dioxide contained in a gas flowing through the circulation path is provided in the circulation path.

17 . The methane generation system according to claim 13 , further comprising:
an auxiliary supply path through which an auxiliary gas containing carbon dioxide is supplied to the circulation path; and an auxiliary concentrator that increases concentration of the carbon dioxide contained in the auxiliary gas.

18 . The methane generation system according to claim 16 , further comprising:
an auxiliary supply path through which an auxiliary gas containing carbon dioxide is supplied to the methane generation unit; and an auxiliary concentrator that increases concentration of the carbon dioxide contained in the auxiliary gas.

19 . The methane generation system according to claim 15 ,
wherein the auxiliary supply path that supplies indoor air as the auxiliary gas.

20 . The methane generation system according to claim 13 ,
wherein the recovery device that obtains the recovery gas by adjusting a temperature with a heat exchanger of an air conditioner.

21 . The methane generation system according to claim 13 ,
wherein the recovery device that obtains the recovery gas by using air blowing from a blower of an air conditioner.

22 . The methane generation system according to claim 13 ,
wherein the recovery device that obtains the recovery gas by adjusting a temperature with a heat exchanger of an air conditioner and the fuel cell.

Assignees

• Mitsubishi Electric Corp

Inventors

• Onaka Yoji
• Tanishima Makoto
• Shinoki Toshio
• Kawamoto Makoto
• Nakashima Seiji

Classifications

• C25B1/04

  by electrolysis of water · CPC title

• C01B2203/066

  with fuel cells · CPC title

• C01B2203/0233

  the reforming step being a steam reforming step · CPC title

• C01B3/38

  using catalysts · CPC title

• B01J19/245

  placed in series · CPC title