Role of Electrochemically Active Bacteria in the Treatment of Piggery and Poultry Wastewaters from Umuagwo in Ohaji Egbema Local Government Area of Imo State, Nigeria

Abstract

In this study, piggery and poultry wastewaters were used as agro-based industrial wastewaters to evaluate the role of electrochemically active bacteria in an anodic chamber of microbial fuel cell (MFC) with 0.1M potassium permanganate cathodic cell using salt bridge preparation. The BOD₅, COD, TDS, TSS, nitrogen, phosphates, pH and conductivity served as indicative parameters for determining the wastewater treatment efficiencies (WWTE) of the MFCs. Results obtained from the WWTE reveal that the MFCs were able to reduce the piggery wastewater parameters, BOD, COD, TDS, TSS, nitrogen, phosphate, pH, conductivity by 89.66, 69.57, 52.20, 69.04, 70.27, 59.57, - 4.41 and 0.99 %, respectively while the same parameters for the poultry wastewater were reduced by 82.61, 78.59, 58.03, 67.13, 70.49, 64.52, 2.70 and 28.04 %, respectively. Statistically, there were significant differences before and after treatments and between wastewater samples revealing that that the effect of treatment before and after on physicochemical parameters were different for piggery wastewater than they were for poultry wastewater. Microbes in the biofilms on the electrodes (potential exoelectrogens) include Staphylococcus aureus, Bacillus cereus, Micrococcus luteus, Corynebacterium sp., Enterococcus sp., Pseudomonas aeruginosa, Escherichia coli, Klebsiella sp., Salmonella sp. and Shigella sp. while the fungal isolates include Mucor sp., Saccharomyces sp. and Aspergillus sp. in both piggery and poultry wastewaters. Thus, microbial fuel cell bacteria oxidize the organic matter leading to decontamination of the wastewater – a significant approach in addressing the public health threats of these wastes in our country.