Waste water treatment and electricity generation using immobilized bioanode in microbial fuel cell

Abstract

Treatment of waste water using electricity from fossil fuel can cause damage to the surrounding as it emits gas that can cause greenhouse effect. Besides that, fossil fuel also is a non-renewable type of energy which will be depleted if use continuously and can lead to energy crisis. Microbial fuel cell (MFC) is one of the alternative sources of energy that can use to treat waste water and produce a return of revenue in the form of electricity generation. In this study three different types of waste water which is synthetic, industrial and domestic were treated using immobilized bioanode in single chamber microbial fuel cell (SCMFC). The objective of this study was to investigate the performance of immobilized bio-anode in single chamber microbial fuel cell (SCMFC) in terms of chemical oxygen demand (COD) loss, power generation and columbic efficiency (CE). The immobilized bio-anode was first prepared using graphite as conductive material and calcium alginate immobilization method. Open circuit test was carried out first and the maximum stable voltage respectively obtained for SCMFC process in synthetic, industrial and domestic waste water were 283.8 mV, 247.2 mV and 184.65 mV. Next, waste water treatment test was carried out to determine the percentage of COD loss and columbic efficiency for every waste water based on different external resistance. Synthetic waste water and domestic waste water show significant effect of waste water treatment after open circuit test was completed with 34.83% and 54.03% respectively in terms of COD reduction but domestic waste water show and increase 27.18% of COD value. After that, the percent of COD loss and columbic efficiency was determined for every different external resistance and it was found that the percentage (%) COD loss and columbic efficiency increases with increasing external resistance. Finally, polarization curve and power curve were plotted and it was found out the highest maximum power obtained was SCMFC process in industrial waste of 0.0002531 mW/cm3 with a corresponding current production of 0.003173 mA/cm3.