Enhancing Nitrogen And Phosphorus Removal To Treat Urban Domestic Sewage In Sequencing Batch Moving Bed Biofilm Reactor

In current society, the problem of water eutrophication is becoming more and more serious, therefore the discharge standard of wastewater treatment is increasingly strict. Removal of organic pollutants, nitrogen and phosphorus and other pollutants in the water body is a key problem in wastewater treatment plants. Biological nitrogen and phosphorus removal in traditional biological nitrogen removal and phosphorus removal are two independent biochemical processes, leading to the competition between the denitrification bacteria and phosphorus removal bacteria on the carbon source, and the processes can not achieve the desired results. The denitrification and phosphorus removal is a new technology of biological treatment in recent years. In this paper, we researched the characteristics of denitrifying phosphorus removal and its influencing factors in sequencing batch moving bed biofilm reactor(SBMBBR) process based on denitrifying phosphorus removal kinetics research. And on the basis of the study, the kinetics of denitrification and phosphorus removal were studied.According to the increasingly serious urban pollution problems, this topic used the sequencing batch moving bed biofilm reactor for the domestication of denitrification phosphorus removal bacteria on urban domestic sewage treatment. After hanging the membrane on the moving bed suspended filler and acclimatingthe denitrifying phosphorus removal bacteria, the effects of COD concentration, temperature, pH, nitrate nitrogen, nitrite nitrogen on denitrifying phosphorus removal efficiency and degradation pathway were researched. Meanwhile, the dynamics of denitrifying phosphorus removal was researched, in order to provide guidance on for actual operation of the process.The experimental results showed that the domestication of the denitrification and phosphorus removal bacteria could be achieved by the two stage domestication method in the sequencing batch moving bed biofilm reactor. In the end of domestication, the total MLSS in the reactor was about 4000mg/L. The configurations performed well with average removal efficiencies of 95%, 90% and 90% for COD, NH4+-N and TP respectively, the effluent concentrations were 8.07 mg/L, 3.67 mg/L, 0.46mg/L in the operation of the cycle for 8 h, achieving the urban sewage A standard. Compared with NO2--N as electron acceptor, NO3--N as electron acceptor could achieve the best result of anoxic phosphorus absorption by 60mg/L. More than 20 mg/L of NO2--N would inhibit the activity of denitrifying phosphorus removal bacteria. The researches showed that the denitrifying phosphorus removal could achieve good results when NO3--N was used as electron acceptor in the SBMBBR.By means of optical microscope and electron microscope observation, suspended carrier biofilm featured with morphology complete, compact structure, and the appearance of brown. It mainly was composed of aureus and bacillus of varying lengths, and attached to the surface of a large number of protozoans and metazoans, various protozoans and metazoans. All of these showed good biological activity of the biofilm sludge.