Strategies for improvement of microbial fuel cell performance via stable power generation from real dairy wastewater

Abstract The microbial fuel cells (MFCs) are one of the emerging sustainable power sources, that are being effectively used for the simultaneous treatment of wastewater with concomitant generation of electricity. The present study develops a fed-batch process with an optimized level of two microorganisms for concurrent treatment of real dairy wastewater (RDW) and stable power generation using a single-chamber MFC. The MFC exhibits a maximum open circuit voltage of 652 mV at 264 h of fed-batch operation. The unstructured kinetic model suggests that the value of saturation constant (Ks) is 41.67 mg COD/L, indicating mixed culture has a higher affinity towards the utilization of RDW. The fed-batch mode achieves maximum COD removal efficiency of 95.31%, columbic efficiency of 31.58%, a maximum current density of 263 mA/m2, and power density (62.27 mW/m2). The optimum cell voltage and internal resistance of MFC are 0.48 V and 340 Ω, respectively. The study suggests that a fed-batch operation with mixed culture is suitable for the treatment of RDW and able to generate stable power from MFC.