Enhancement of microbial fuel cell performance by introducing dosing materials in waste water to increase microorganism growth

Abstract

This study uses the microbial electrochemical process to produce energy from wastewater. The bacterial growth in sewage has been controlled by applying molasses, vegetables and waste coffee as dosing materials. High-conductive silver metal has been used as an anode, whereas graphite has been used as a cathode. An agar salt membrane has been used as a separator to ensure high hydrogen-ion exchange. During bacterial culture, it is revealed that 21,600,000 cfu/ml, 14,800,000 cfu/ml, and 38,700,000 cfu/ml number of bacteria is observed for molasses, vegetable protein and waste coffee, respectively. In each dosing, E.coli, S.aureus, and Salmonella sp. were identified. The bacterial growth highly influenced electrical energy production in this method. The wastage of coffee produced more energy and grew more bacteria. Waste coffee had a maximum current density of 809.40 mA/m2 and a maximum power density of 10622.496 mW/m2, respectively. In contrast, the minimum current and power density values, 166.15 mA/m2 and 408.726 mW/m2, were attained, respectively. The produced energy is much higher than the information available in the literature. The applied method can be used in various sectors to generate electrical energy.