ELECTROMETHANOGENIC REACTOR AND PROCESSES FOR METHANE PRODUCTION

• US 20090317882A1
• Filed: 06/22/2009
• Published: 12/24/2009
• Est. Priority Date: 06/20/2008
• Status: Active Grant

• Current Assignee: Penn State Research Foundation (Pennsylvania State University)
• Original Assignee: Penn State Research Foundation (Pennsylvania State University)
• Inventors: Cheng, Shaoan, Logan, Bruce
• Granted Patent: US 8,440,438 B2
• Time in Patent Office: Days
• US Class Current: 435/167
• CPC Class Codes: C12M 21/04 for producing gas, e.g. biogas digesters for manure with production of biogas A01C3/028, biological treatment of water, waste water or sewage C02F3/00, C02F11/02, preparation of natural gas or syngas C10L3/06, C10L3/10
• CPC Class Codes: C12M 23/34 Internal compartments or partitions
• CPC Class Codes: C12M 35/02 Electrical or electromagnetic means, e.g. for electroporation or for cell fusion
• CPC Class Codes: C12N 13/00 Treatment of microorganisms or enzymes with electrical or wave energy, e.g. magnetism, sonic waves
• CPC Class Codes: C12P 39/00 Processes involving microorganisms of different genera in the same process, simultaneously
• CPC Class Codes: C12P 5/023 Methane
• CPC Class Codes: C25B 1/04 by electrolysis of water
• CPC Class Codes: C25B 11/04 characterised by the material
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
• CPC Class Codes: Y02P 20/133 Renewable energy sources, e.g. sunlight

Abstract

Increasing competition for fossil fuels, and the need to avoid release carbon dioxide from combustion of these fuels requires development of new and sustainable approaches for energy production and carbon capture. Biological processes for producing methane gas and capturing carbon from carbon dioxide are provided according to embodiments of the present invention which include providing an electromethanogenic reactor having an anode, a cathode and a plurality of methanogenic microorganisms disposed on the cathode. Electrons and carbon dioxide are provided to the plurality of methanogenic microorganisms disposed on the cathode. The methanogenic microorganisms reduce the carbon dioxide to produce methane gas, even in the absence of hydrogen and/or organic carbon sources.

Claims

1. A biological process for producing methane gas comprising:

providing an electromethanogenic reactor having an anode, a cathode, and a plurality of methanogenic microorganisms disposed on the cathode;

providing electrons to the plurality of methanogenic microorganisms disposed on the cathode; and

providing carbon dioxide to the plurality of methanogenic microorganisms, whereby the methanogenic microorganisms reduce the carbon dioxide to produce methane gas.

2. The process of claim 1, wherein a power source is in electrical communication with the reactor to enhance a potential between the anode and the cathode.

3. The process of claim 1, wherein electrons provided to the plurality of methanogenic microorganisms comprises electrons transferred to the anode by a plurality of exoelectrogenic bacteria.

4. The process of claim 2, wherein the power source is selected from the group consisting of:

wind-generated power, solar power, a microbial fuel cell, a DC power source, an electrochemical cell, and a combination of two or more thereof.

5. The process of claim 1, further comprising increasing methane gas production rate by adding an additional voltage to the cathode.

6. The process of claim 1 wherein the electromethanogenic reactor comprises an anode chamber and a cathode chamber.

7. The process of claim 6 wherein no organic carbon source is added to the cathode chamber.

8. The process of claim 1 wherein no hydrogen is added to the cathode chamber.

9. The process of claim 1, wherein substantially no organic carbon source is available to the plurality of methanogenic microorganisms,

10. The process of claim 1, wherein metal catalysts are substantially excluded from the cathode.

11. A biological process for producing methane gas, comprising:

providing an electromethanogenic reactor containing exoelectrogenic microorganisms and methanogenic microorganisms;

providing an organic material oxidizable by an oxidizing activity of the exoelectrogenic bacteria such that electrons are produced and transferred to the anode and to the methanogenic microorganisms; and

providing carbon dioxide to the methanogenic microorganisms, whereby the methanogenic microorganisms reduce the carbon dioxide to produce methane gas.

12. The process of claim 11, wherein the exoelectrogenic microorganisms are disposed in an anode chamber of the electromethanogenic reactor.

13. The process of claim 11, wherein the methanogenic microorganisms are disposed in a cathode chamber of the electromethanogenic reactor.

14. A biological process for producing methane gas, comprising:

inserting an anode and a cathode in a methanogenic reactor comprising methanogenic microorganisms; and

providing electrons to the methanogenic microorganisms, increasing the efficiency of the methanogenic reactor to produce methane gas.

15. The process of claim 14, wherein providing electrons comprises applying a voltage to the cathode.

16. The process of claim 15, wherein the voltage is generated by a power source selected from the group consisting of:

wind-generated power, solar power, a microbial fuel cell, a DC power source, an electrochemical cell, and a combination of two or more thereof.

17. The process of claim 14, wherein providing electrons comprises providing an electrically conductive conduit between the anode and cathode for electrons generated by exoelectrogenic microorganisms.

18. An electromethanogenic reactor, comprising

an anode;

and

a cathode comprising methanogenic microorganisms.

19. The electromethanogenic reactor of claim 18, wherein the anode comprises exeoelectrogenic microorganisms.

20. The electromethanogenic reactor of claim 18, further comprising a power source in electrical communication with the reactor to add a voltage to the cathode.

21. The electromethanogenic reactor of claim 18, wherein the cathode has a cathode wall generally enclosing and defining an interior space, the cathode wall having an internal surface adjacent the interior space and an opposed external surface, the cathode wall extending between a first end and a second end and wherein the methanogenic microorganisms are disposed in the interior space.