Effectiveness of piggery waste treatment using microbial fuel cells coupled with elutriated-phased acid fermentation

The present study evaluates the feasibility of increased power generation in microbial fuel cells (MFCs) coupled with acid elutriation fermentation. Raw piggery waste (RPW) and acid elutriation effluents (AEE) of piggery waste were used to generate bioelectricity in single-chambered air-cathode MFCs. RPW-fed MFCs exhibited stable performance after 12-days of operation, generating 540mV of open circuit voltage (OCV). RPW fed-MFCs displayed peak potential and maximal power density (PD_max) of 0.364V and 192mW/m² with 980Ω external resistance (R_ext), respectively. AEE-fed MFCs documented 818mV of maximum OCV. Furthermore, the peak potential and PD_max of 0.329V and 1553mW/m² were generated with 100Ω R_ext, respectively. RPW and AEE-fed MFCs exhibited 84% and 93% substrate removal efficiency, respectively. These findings suggest that a two-stage process including acid elutriation reactor asa pre-fermentation and MFCs greatly enhances substrate removal and electricity generation from piggery waste.