Purification Efficiency And Microbial Community Analysis Of Immobilized Polyurethane Carrier

With the increase of emissions requirements of municipal sewage, Improving water quality is effective way for development of water resources, but conventional sewage treatment process exist poor efficiency for COD and NH₄-N, with the increased of let-out of industry waste water and living sewage of the city with years, therefore, upgrading traditional sewage treatment process is necessary to do, in order to solve the disadvantages of poor efficiency and achieve the new effluent standard.Biological contact oxidation were taken as the main study in the present research .which were combined between suspension activated sludge process with fixed biological membrane law. immobilized carrier play an important role in biological contact oxidation. immobilized polyurethane carrier which were porous foam were taken as the main study object, The immobilized polyurethane carrier was put into biological contact oxidation by up-floating, sinking and general up-floating general sinking, the concentrations of the influent COD,NH₄-N,BOD,TN,biomass, biological activity and microbial community structure of immobilized polyurethane carrier was compared, bacterial species of three dropping way were also identified. The relationship between the succession of microbial community structure and the pollutants removal efficiency were investigated, thus, the best dropping way in biological contact oxidation was confirmed, which gave further technical supports and theoretical basis for the stable performances and upgrade of wastewater treatment plant.The results of the microbial community distribution and the pollutants removal efficiency in biological contact oxidation demonstrated that immobilized polyurethane carrier by general up-floating general sinking was the best dropping way, concentrations of the influent COD and NH₄-N was varied in 300-350 mg/L and 46-58 mg/L, the corresponding effluent could keep stable below 50mg/L and 5mg/L, respectively. the biomass and biological activity was 272.5g and 86mgO₂ /g·h. the differences of the diversity of microbial community were obvious. Particularly, microbial community structure of immobilized polyurethane carrier by general up-floating general sinking were the most abundant. The identify results of functional bacteria of immobilized polyurethane carrier in the best dropping way demonstrated that Agrobacterium rubi, Ochrobactrum sp.,Bacteroidetes, Bradyrhizobium sp. , Paracoccus sp. ,Nitrosospira sp.,Nitrobacter, Nitrosomonas sp. Pseudomonas fluorescens ,Clostridium sp.and so on. Among them, denitrify bacteria play an important role in biological contact oxidation, meanwhile, several kinds of aerobic denitrifying bacteria were found, which prove two kinds of nitrogen process in the immobilized polyurethane carrier and provide theoretical basis for the further practical engineering application.