Performance study of microbial fuel cell stack system for treating fine chemical wastewater.

This study developed a stacked anaerobic fluidized bed microbial fuel cell (SAFB-MFC) system for treating refractory fine chemical wastewater containing high concentrations of benzene compounds, while simultaneously generating electricity. The system integrated 45 air-cathode MFC units within a shared anode chamber using a three-dimensional layout, achieving high integration density. Experimental results demonstrated that the total power output increased linearly with the number of connected units, peaking when all are connected. Units in the middle and upper sections exhibited superior performance to those at the bottom, whereas horizontal performance was uniform. Increasing superficial velocity enhanced mass transfer, raising the maximum power density by 18.3 ± 2.1 %. Parallel operation increased the chemical oxygen demand (COD) removal rate by 9.1 % and total power output by 43.5 times compared to a single unit. The system demonstrates significant potential for scalable and efficient application in real industrial wastewater treatment.