Research on livestock wastewater treatment and producing electricity using anaerobic fluidized bed

In order to recycle source of energy from livestock wastewater, using a two-chambered anaerobic fluidized bed microbial fuel cell (AFB-MFC) and taking digested piggery wastewater, low-concentration piggery wastewater and high-concentration piggery wastewater as substance successively, performances of COD(Chemical Oxygen Demand) removal efficiency and electricity production was evaluated at different COD volume loading and feeding ammonia concentration. Using the digested wastewater as the substance, the ammonia caused 7.0% inhibition of electricity production as the ammonia concentration was up to 387.6mg/L, but the power generation recovered five days later. Using the raw wastewater as the substance, the COD volume loading increased from 2.3 kg·m-3·d-1 to 14.9 kg·m-3·d-1 within 12 days, and the COD removal efficiencies remained between 74.5% and 88.1%. The output voltage increased slightly with the increasing of COD volume loading, the maximum output voltage and the power density were 379.3mV and 74.9 mW·m-2 respectively. Because of the difference of the substance pH, the maximum output voltage of the low-concentration piggery wastewater was 21.4 mV higher than the high-concentration piggery wastewater. The AFB-MFC’s internal resistance was 48.5 Ω, and the maximum power density was 75.6mW·m-2. This study demonstrates that AFB-MFC can treat the livestock wastewater effectively and produce electricity, providing a novel approach for the safe disposal and recycle of livestock wastewater.