Potential of agro-based industrial wastewater as an alternative substrate for bioelectricity

Abstract

The potentials of agro-based industrial wastewater as an alternative substrate for bioelectricity were investigated. Piggery and poultry wastewater as well as 0.1 M potassium permanganate were collected, prepared and served as substrates in the anodic and cathodic chambers of the Microbial Fuel Cell (MFC) set up. Standard analytical procedures were adopted in the physicochemical determination, while the generation of electricity was evaluated using current densities (mA/cm²) and power densities (mW/m²) respectively. The results revealed that the power density of the piggery wastewater reached a peak value on the 288^th hour with a value of 151.98 mW/m² with a BOD, COD, TDS and TSS values were 65.52, 52.22, 11.40 and 57.39% respectively, while the poultry wastewater reached a peak power density of 120.24 mW/m2 on the 240^th hour with a BOD, COD, TDS and TSS values of 21.74, 40.06, 2.34 and 52.87% respectively. On the other hand, results on the current densities (mA/cm²) and power densities (mW/m²) showed that the poultry wastewater MFC had peak values of 50.52 mA/cm2 and 151.98 mW/m² on the 10^th day, while the piggery powered MFC peaked on the 12^th day with peak values of 69.47 mA/cm² and 234.48 mW/m² respectively. Statistically, the power and current densities of piggery wastewater were significantly greater (p<0.05) than that of the poultry wastewater. There were significant positive (p<0.05) relationship between physicochemical parameters and power density with time. Thus, the excellent transformation of these liquid wastes using MFC for energy generation could be exploited as benign and environmentally friendly approach.