Studies on agar salt bridge based dual chamber microbial fuel cells using sludge and dustbin waste

In the present study, the performance of dual chamber microbial fuel cells (MFC) was investigated employing sludges collected from drains, a textile effluent treatment plant, and the Buriganga river as the sources of microbes, while a mixed liquor prepared from dustbin waste and gruel was used as substrates for the growth of bacteria. Six experiments were carried out under aerobic conditions throughout the study and inspected for seven days. Agar salt bridge was used instead of the typical membrane for proton exchange. For analyzing the electrical parameters of the MFCs such as voltage, current density and power density were recorded for each experiment. Reduction of Biological Oxygen Demands (BOD₅) of the sludges was also observed in this study. Regarding electrical performance, the Buriganga sludge afforded the best results demonstrating maximum voltage, current density, and power density as 244.88 mV, 35.16 mA/m², and 8.61 mW/m², respectively. However, the BOD₅ reduction was found to be 50.15%, 43.64%, 47.32%, and 35.20% for sludges collected from a drain of a residential area, a textile effluent treatment plant, a tannery, and the Buriganga river, respectively. Counts of aerobic Escherichia coli and Bacillus subtilis in different sludges were also documented.