STUDY OF ELECTROGENIC PROPERTIES OF MICROFLORA OF MUD MASSES OBTAINED FROM VARIOUS BIOTYPES

Abstract

Microbial fuel cells (MFC) are an environmentally friendly way of generating electricity, which is often accompanied by the decomposition of organic waste. A common problem for these devices is the low power generated by the electric current. In nature, the decomposition of organic waste, coupled with oxidation-reduction reactions, i.e. the transfer of electrons and protons formed during the decomposition is carried out by microbial communities, which, in their optimal state for this process, are called active sludge (AS). A mature active sludge consists of a so-called flocculium - round formations in the size from 30 to 100 and more microns, inside of which microorganisms carrying out various reactions of decomposition of organic substances are contained. It is easy to see that the MFC design is topologically similar to the active sludge flocculant. We tried to check how the presence of microorganisms in the water chamber affects the productivity of the MFC by filling the anode and cathode chambers with the same sludge mixture, and the test cells were shaken on a shaker to create favorable conditions for the formation of microbial communities. The active sludge cell in both chambers shaken on the shaker, over time, generated the highest voltage in the external circuit as compared to the control samples. The obtained data confirm the legitimacy of the assimilation of MFC flocculine AS. The evolution of the microbial community of the silt mixture in two directions - in the aerobic and anaerobic MFC chambers - apparently leads to the formation of two different communities mutually complementing each other as part of the MFC and improving the operation of the MFC, subject to additional dynamic provision (shaking). The effect of the addition of peptone to the anode chamber on the productivity of MFC was also investigated. The periodic addition of peptone significantly increased the output power of the MFC cell. Apparently, substrates of protein nature, representing a nutrient medium for electrogenic bacteria, can be used to stimulate the electrogenic activity of the microflora of late anaerobic silt.