Pilot Experiment of Anaerobic Membrane Bioreactor（AnMBR）for Treating High-Concentration Organic Wastewater

Abstract:

The operation of a pilot-scale anaerobic membrane bioreactor（AnMBR） for treating high-concentration organic wastewater was investigated. The result showed that AnMBR could finish the fast start-up of a highly efficient anaerobic digestion system and its good anti-shock loading capability could ensure a long-term and stable operation of the digestion system. Without the biomass withdrawal condition（SRT infinitely long），the COD removal loading rate and the biogas production strength of AnMBR were about 4.4~4.8 kg COD/（m3?d） and 2.2 m3/（m3?d），respectively，while they were 5.2~6.0 kg COD/（m3?d） and 2.9 m3/（m3?d） with biomass withdrawal（SRT=50 d）. In the whole process of 220 days，the COD removal rate was about 90% and the CH4 content was about 58%. The pH was kept at 7.6~7.8 and VFA was at a low level in the digestion system. Furthermore，the high accumulation of ammonia had no significant effect on the digestion performance，which indicated that AnMBR had good tolerance to the endogenous inhibitory factor. A comparison of the operating parameters without biomass withdrawal and with biomass withdrawal conditions showed that the optimization of sludge retention time（SRT） was very important to the AnMBR operation. Different SRTs would lead to a series of variations in the digestion system，which largely determined the processing performance of the AnMBR.