Anode for biological power generation and power generation method and device utilizing it

Abstract

A method and a device for obtaining electric energy efficiently from an organic substance containing water by suppressing the activation overvoltage of an anode low and thereby obtaining a sufficiently low anode potential. The power generating device comprises an anaerobic region (4) including microorganisms which can grow under anaerobic conditions, solution or suspension containing an organic substance, an electron mediator and an anode (1), an aerobic region (5) including oxygen in molecular state and a cathode (3), and a diaphragm (2) defining the anaerobic region (4) and the aerobic region (5), wherein a closed circuit (6) is formed by connecting the anode (1) and the cathode (3) electrically with a power utilization apparatus, and oxidation reaction of microorganisms using the organic substance in the anaerobic region (4) as electron donor and a reduction reaction using oxygen in the aerobic region (5) as electron receptor are utilized. The anode (1) includes a conductive substrate having a surface coated at least partially with a hydrophilic polymer layer, an electron mediator is introduced into the hydrophilic polymer layer while boded chemically, and standard electrode potential (E0') at pH7 is in the range of -0.13V to -0.28V.

Description

technical field [0001] The present invention relates to using waste water, waste liquid, human excrement, food waste, other organic waste, sludge and other organic substances or their decomposition products as substrates, and separating the redox reaction of the substrate and oxygen in the air into Bioelectric power generation technology that utilizes the oxidation reaction of anaerobic organisms and the reduction reaction of oxygen to generate electricity. Background technique [0002] As a method of decomposing waste water, waste liquid, human excrement, food waste, other organic waste, and sludge (hereinafter referred to as "water-containing organic matter") to obtain usable energy, the following methods are considered: using methane Anaerobic fermentation, including fermentation, produces methane, etc., and then uses it to generate electricity; a biobattery method that directly obtains electricity from the anaerobic respiration reaction of organisms, etc. [0003] Howev...

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Problems solved by technology

[0003] However, the method of producing methanol, ethanol, hydrogen, etc. by anaerobic fermentation including methane fermentation, and then using them to generate electricity requires a two-stage process of material production using biomass and power generation using the products as fuel. The problem is: the energy efficiency is poor, and the device is also complicated

However, the standard electrode potentials of the electron mediators used in these methods do not overlap with the standard electrode potentials of the final electron acceptors of anaerobic microorganisms generally used in biobattery reactions, so there is a problem that cascades of effective potentials cannot be formed. )

However, in the proposed system, when AQ-2,6-DS is only added in the liquid phase, since it will not be supported on the anode (oxidation electrode), the reactivity with the electrode is reduced, and the addition effect is only 24%. The current value increases

In addition, when generating electricity continuously, when renewing the substrate fluid in the anaerobic region, there is a problem that the electron mediator is also discharged out of the system, and the electron mediator must always be continuously added.

However, when the electrode made by the method disclosed in this patent is applied to the anode of a microbial battery, the terminal reductase of the microorganism can only reduce the quinone near the surface of the above-mentioned polymer layer, and when the polymer layer shows hydrophobicity, the reduction reaction itself tougher

Furthermore, even if the quinone on the surface of the polymer is reduced, since there is a polymer layer of a non-conductive substance between the platinum plate as the current collector, there is a problem that electrons must be moved to the current collector. , the oxidation efficiency of reduced quinone is poor, and the activation overvoltage also increases

In addition, as described above, since it is used as an anode of a microbial battery, it is necessary to maintain the hydrophilicity of the polymer layer after immobilizing quinone, but there is no disclosure of the method and conditions for this.

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