Electricity Generation from Septic Waste Water Using Septic Tank as Microbial Fuel Cell

摘要

The use of microbial fuel cell (MFC) for electricity generation from septic waste water was carried out for 12 weeks retention period. In this study, the microbial fuel cells were designed and loaded with a 1000 Ω external load (resistor). Electrical voltage, current, power output was measured on weekly basis. Current density and power density were calculated. Wastewater qualities such as Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Dissolved Solids (TDS) and pH of the raw wastewater were determined in the laboratory on weekly basis. pH values were constant (8.2) while the BOD, COD and TSS decreased. The performance of the MFC showed 92.7%, 93.9% and 98.6% reduction in BOD, COD and TSS respectively indicating that this process was efficient in the biodegradation of the septic waste water. The maximum voltage reading of 3.029V was obtained on the 6th week but gradually decreased due to the formation of biofilm and reduction of substrate (food) in the cell. The linear correlation between voltage and the other parameters (current, current density and power density) have R2 values of 0.9301, 0.9303 and 0.6274 respectively. The MFC design provides a solution for power generation from wastewater in homes. This single multistage MFC produced 3.029V of electricity which was able to power a 2.0 V LED bulb.