Optimization and process modelling of bacterio-algal fuel cell

Abstract

Bacterio-algal Fuel Cells (BAFCs) offer a sustainable bio-energy solution by converting organic waste into electricity, treating wastewater, and capturing CO2 emissions, addressing the urgent need for renewable energy sources. This study focused on measuring the voltage, current, and power output in a bacterio-algal fuel cell. For the analysis, multiple dual-chamber bacterial fuel cells were employed, using glucose and lactic acid as substrates. The anode chamber was inoculated with a pure culture of the microorganism Shewanella putrefaciens, while Leptolyngbya subtilis was used as the cathode organism. The microbe facilitated the oxidation of the substrate, and the resultant energy produced was assessed. A study on the growth kinetics of the microorganism Shewanella putrefaciens MTCC 8104 was conducted using Glucose and lactic acid separately as substrate. This aimed to ascertain the maximum specific growth rate (μmax) and the substrate saturation constant (ks), both are crucial kinetic parameters of the system. Lactic acid displayed inhibition, prompting the determination of the substrate inhibition constant, KI . The highest power density achieved from the BAFC setups was 396 mW/m2 for lactic acid, 121.98 mW/m2 for glucose, and 74.82 mW/m2 for the dual substrate (lactic acid & glucose) configuration. The BAFC was mathematically modeled using MATLAB 2017b sofware in order to theoretically examine the operations and efficiency of the bacterio-algal fuel cell. Response surface analysis was conducted utilizing Design Expert 13 software to anticipate a model of power density under optimal conditions.