Method and apparatus for converting chemical energy stored in wastewater

• US 10,347,932 B2
• Filed: 11/04/2016
• Issued: 07/09/2019
• Est. Priority Date: 11/11/2015
• Status: Active Grant

• Current Assignee: BioEnergySP, Inc.
• Original Assignee: BioEnergySP, Inc.
• Inventors: Lozano, Jose Luis
• Primary Examiner(s): Rhee, Jane J
• Application Number:
  US15/343,809
• Publication Number:
  US 20170141424A1
• Time in Patent Office: 977 Days
• CPC Class Codes: C02F 3/006 Regulation methods for biological treatment
• CPC Class Codes: C02F 3/301 Aerobic and anaerobic treatment in the same reactor
• CPC Class Codes: H01M 8/04276 Arrangements for managing the electrolyte stream, e.g. heat exchange
• 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

Abstract

A method and apparatus is provided for harvesting electricity from a biofilm retained in a zero chamber, no interphase container, the biofilm having a portion supporting aerobic microbial activity and a second portion supporting anaerobic microbial activity, wherein the first and the second portion are in direct physical contact. A ground or a power harvester is electrically connected, directly or indirectly, to the second portion of the biofilm.

Claims

1. A method comprising:

(a) forming a biofilm on a substrate exposed to wastewater that is contained in a container and having dissolved oxygen, the biofilm having a sufficient thickness to define a gradient between aerobic microorganisms exposed to the wastewater and anaerobic microorganisms proximal to the substrate; and

(b) grounding the biofilm to a ground, the ground being external to the container and the wastewater.

2. The method of claim 1, wherein grounding the biofilm includes connecting an electrical conductor to the biofilm and the ground.

3. The method of claim 1, wherein grounding the biofilm includes connecting an electrical conductor to the biofilm and the ground.

4. The method of claim 1, wherein grounding the biofilm includes electrically connecting the substrate to the ground.

5. The method of claim 1, wherein the volume of wastewater is independent of a PEM membrane.

6. The method of claim 1, wherein the volume of wastewater is independent of a catalyst.

7. The method of claim 1, wherein the container is independent of an interphase for oxygen diffusion.

8. The method of claim 1, wherein the wastewater is organic.

9. The method of claim 1, wherein grounding the biofilm includes electrically connecting a portion of the anaerobic microorganisms to a ground.

10. A microbial fuel cell comprising:

(a) a container for retaining a volume of wastewater, the wastewater including dissolved oxygen;

(b) a substrate at least partially submerged in the wastewater, the substrate supporting a biofilm exposed to the volume of organic wastewater, the biofilm having a sufficient thickness to define an electron concentration gradient between microorganisms exposed to the wastewater and microorganisms proximal to the substrate; and

(c) a first electrical conductor between a ground and one of (i) the biofilm and (ii) the substrate, the ground being external to the container and the wastewater.

11. The microbial fuel cell of claim 10, wherein the substrate is conducting.

12. The microbial fuel cell of claim 10, wherein the substrate is non-conducting.

13. The microbial fuel cell of claim 10, wherein the container is independent of a proton exchange membrane.

14. The microbial fuel cell of claim 10, wherein the container is independent of a catalyst.

15. The microbial fuel cell of claim 10, wherein the container is independent of an interphase for oxygen diffusion.

16. The microbial fuel cell of claim 10, wherein the container is independent of a membrane compartment.

17. A microbial fuel cell comprising:

(a) a container retaining a volume of wastewater, the container being free of a proton exchange membrane and the wastewater including dissolved oxygen;

(b) a substrate at least partially submerged in the wastewater, the substrate supporting a biofilm exposed to the volume of organic wastewater, the biofilm having a sufficient thickness to define an oxygen concentration gradient between microorganisms exposed to the wastewater and microorganisms proximal to the substrate wherein the gradient is sufficient to generate sufficient free electrons; and

(c) a first electrical conductor between a ground and one of (a) the biofilm and (b) the substrate, the ground being external to the container and the wastewater.

18. The microbial fuel cell of claim 17, wherein the substrate is conducting.

19. The microbial fuel cell of claim 17, wherein the substrate is non-conducting.

20. The microbial fuel cell of claim 17, wherein the ground lead is a common electrical ground.

21. The microbial fuel cell of claim 17, wherein the chamber is independent of a proton exchange membrane.

22. The microbial fuel cell of claim 17, wherein the chamber is independent of a catalyst.

23. The microbial fuel cell of claim 17, wherein the chamber is independent of an interphase for oxygen diffusion.

24. The microbial fuel cell of claim 17, wherein the chamber is independent of a membrane compartment.