MICROBIAL FUEL CELL TREATMENT OF FUEL PROCESS WASTEWATER

• US 20100200495A1
• Filed: 02/06/2009
• Published: 08/12/2010
• Est. Priority Date: 02/06/2009
• Status: Active Grant

• Current Assignee: UT-Battelle LLC
• Original Assignee: UT-Battelle LLC
• Inventors: Borole, Abhijeet P., Tsouris, Constantino
• Granted Patent: US 8,597,513 B2
• Time in Patent Office: Days
• US Class Current: 210/601
• CPC Class Codes: C02F 1/46104 Devices therefor; Their operating or servicing
• CPC Class Codes: C02F 1/46114 Electrodes in particulate form or with conductive and/or non conductive particles between them
• CPC Class Codes: C02F 2001/46138 Electrodes comprising a substrate and a coating
• CPC Class Codes: C02F 2001/46161 Porous electrodes
• CPC Class Codes: C02F 2101/32 Hydrocarbons, e.g. oil
• CPC Class Codes: C02F 2103/365 from petrochemical industry (e.g. refineries)
• CPC Class Codes: C02F 2201/46115 Electrolytic cell with membranes or diaphragms
• CPC Class Codes: C02F 2303/10 Energy recovery
• CPC Class Codes: C02F 3/005 Combined electrochemical biological processes aeration by electrolytically produced oxygen bubbles C02F3/202
• CPC Class Codes: C02F 3/341 Consortia of bacteria
• CPC Class Codes: C02F 3/348 characterised by the way or the form in which the microorganisms are added or dosed
• CPC Class Codes: C10L 3/08 Production of synthetic natural gas
• CPC Class Codes: H01M 8/16 Biochemical fuel cells, i.e. cells in which microorganisms function as catalysts
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02W 10/30 Wastewater or sewage treatment systems using renewable energies

Abstract

The present invention is directed to a method for cleansing fuel processing effluent containing carbonaceous compounds and inorganic salts, the method comprising contacting the fuel processing effluent with an anode of a microbial fuel ell, the anode containing microbes thereon which oxidatively degrade one or more of the carbonaceous compounds while producing electrical energy from the oxidative degradation, and directing the produced electrical energy to drive an electrosorption mechanism that operates to reduce the concentration of one or more inorganic salts in the fuel processing effluent, wherein the anode is in electrical communication with a cathode of the microbial fuel cell. The invention is also directed to an apparatus for practicing the method.

Claims

1. A method for cleansing fuel processing effluent containing carbonaceous compounds and inorganic salts, wherein at least a portion of said carbonaceous compounds includes one or more hydrocarbon compounds, the method comprising contacting the fuel processing effluent with an anode of a microbial fuel cell, said anode containing microbes thereon which oxidatively degrade one or more of said carbonaceous compounds while producing electrical energy from said oxidative degradation, and directing. said electrical energy to drive an electrosorption mechanism that operates to reduce the concentration of one or more inorganic salts in said fuel processing effluent, wherein said anode is in electrical communication with a cathode of the microbial fuel cell.

2. The method of claim 1, wherein said microbes are in the form of a biofilm on said anode.

3. The method of claim 1, wherein said carbonaceous compounds include one or more hydrocarbon compounds selected from the group consisting of benzene, toluene, xylenes, and polycyclic hydrocarbons.

4. The method of claim 1 wherein the fuel processing effluent is subjected to a pre-oxidation treatment step before being treated by the microbial fuel cell.

5. The method of claim 4, wherein the pre-oxidation treatment step uses ozone as an oxidant.

6. The method of claim 1, wherein said anode comprises a form of elemental carbon.

7. The method of claim 1, wherein the cathode of said microbial fuel cell is a Pt/air electrode.

8. The method of claim 1, wherein the cathode of said microbial fuel cell is operated in the substantial absence of oxygen.

9. The method of claim 1, wherein the microbial fuel is operated such that hydrogen gas is produced at the cathode by operating the microbial fuel cell under the conditions that the cathode is constructed of a hydrogen-producing material and is deoxygenated, and the cell potential of the microbial fuel cell is adjusted by application of an external voltage such that hydrogen is produced at the cathode, wherein the resulting hydrogen gas is used as an electricity-generating fuel to power the electrosorption mechanism.

10. The method of claim 9, wherein said hydrogen is processed in a hydrogen-oxygen fuel cell to convert the hydrogen to electricity.

11. The method of claim 1, wherein the microbial fuel is operated such that the cathode electrochemically reduces one or more electrochemically reducible species other than hydrogen ions.

12. The method of claim 11, wherein said electrochemically reducible species includes one or more electrochemically reducible metal cations.

13. The method of claim 1, wherein a first system of one or more microbial fuel cells operates, at least initially, on a non-effluent nutritive source to generate electrical power, which is used to operate one or more electrosorption units, and processed effluent emanating from the one or more electrosorption units is fed back to said one or more microbial fuel cells.

14. The method of claim 13, wherein said one or more microbial fuel cells operate more effectively in effluent having a total salt concentration below a critical salt concentration, and the non-effluent nutritive source has a total salt concentration below said critical salt concentration.

15. The method of claim 1, wherein a first system of one or more microbial fuel cells operates solely on a non-effluent nutritive source to generate electrical power which is used to operate one or more electrosorption units, and processed effluent emanating from the one or more electrosorption units is fed to a second system of one or more microbial fuel cells.

16. The method of claim 15, wherein one or more microbial fuel cells of the first system operate more effectively in effluent having a total salt concentration below a critical salt concentration, and the non-effluent nutritive source has a total salt concentration below said critical salt concentration.

17. The method of claim 1, wherein a first system of one or more microbial fuel cells processes the effluent to generate electrical power, which is used to operate one or more electrosorption units, and processed effluent emanating from the one or more electrosorption units is fed to a second system of one or more microbial fuel cells.

18. The method of claim 17, wherein the one or more microbial fuel cells of the first system can operate in effluent of a given salt concentration, whereas the one or more microbial fuel cells of the second system operate more effectively in effluent having a total salt concentration below the given salt concentration.

19. The method of claim 1, wherein a cation-selective permeable material separates an anode region which contains the anode from a cathode region which contains the cathode.

20. The method of claim 1, wherein the cathode of said microbial fuel cell is a biocathode.

21. A device for cleansing fuel processing water, the device comprising a microbial fuel cell electrically connected to an electrosorption device such that electrical power generated by the microbial fuel cell is capable of operating said electrosorption device.