Research on stillage storage time for MFC performance and control methods

Electricity generation from a microbial fuel cell (MFC) with old (stored for one year) and new (freshly obtained) food waste ethanol stillages were studied. The composition and toxicity of the stillages were detected. Tween 80 was added to investigate the feasibility for regulation. Results showed that the maximum power densities of MFC with old and new stillages were 560.7 and 426.6 mW/m2, respectively. The new stillage is more toxic than the old stillage. The maximum output power density based on the cathode area increased from 560.8 mW/m2 to 1208 mW/m2 after adding 20 mg/L Tween 80 to the old stillage, and the relative luminescence inhibitory rate of its biotoxicity decreased from 93.48% to 89.53%.