Wastewater treatment in microbial fuel cell and direct electric power generation: fundaments and application

Abstract

Nowadays, society is experiencing a number of environmental challenges such as pollution of the aquatic environment and atmosphere, compounded by the introduction of in natura wastewater and emission of gases from the burning of fossil fuels for power generation. Having been growing energy demand it is necessary to search alternative sources of energy, which can minimize the environmental problems that already exist. The microbial fuel cell (MFC) is a new energy alternative such as convert chemical energy of substrate into electrical power by means of catalytic reactions of microorganisms. This research project aims to evaluate the anaerobic fixed-bed and upward flow in the electrodes containing immobilized biomass applied to wastewater treatment and the direct production of power in mesophilic and thermophilic conditions. The attachment of biomass, the removal efficiency of organic matter, and the current density and electric power will be evaluated in different electrode materials using the technique of differential reactors. The best support material will be used in bench-scale reactors. The physic-chemical and electrical parameters will be analyzed according to: (I) the variation of hydraulic retention time (HRT) of the anode chamber (anaerobic), modifying the influent flow of the MFC; (II) the variation of the HRT of the cathode chamber (aerobic), changing the volume of this compartment:; (III) the rate of oxygenation by testing different air flow; and (iv) the use of electron transfer mediators, applying different substances and concentrations. Set the operating parameters of the MFC will use the reactor to treat real wastewater (vinasse). All tests will be carried out under mesophilic and thermophilic, 25°C and 55°C, respectively. (AU)