Low Dissolved Oxygen Membrane Bioreactor For Domestic Wastewater Treatment Applied Research

The performance of a full-scale submerged hollow fiber membrane-bioreactor (SMBR) to treat Wastewater was studied in this paper. The study mainly referred the pollutants removal in the different DO and the factors of membrane fouling.The effluent quality proved excellent and stable. The average effluent parameters were COD<30mg/L, NH₄⁺ -N <1.1mg/L, turbidity< 0.4 NTU, which met the standards for sewage Wastewater issued by the Chinese Construct Ministry(GB/T 18920- 2002).Simultaneous nitrification denitrificaion went well when the DO were 0.4-0.8mg/L,so the 94% of NH₃-N and the 72% of TN could be removed. But after the DO declined to 0-0.5mg/L, the nitrification were influenced and only 51% of NH₃-N and 35% of TN could be removed.The study showed that the membrane relationship to the membrane fouling could be found with the MLSS, SVI and SCOD. The Gray Relationship Analysis showed that MLSS gave an more important influence on the membrane fouling than SVI and SCOD.