Study On Denitrifying Phosphorus Removal Process And Microbiology

For the purpose to resolve the contradictions that existed in conventional phosphorus and nitrogen removal process, enhance the study of denitrifying phosphorus removal, and promote the application of two-sludge system, lab scale of two-sludge process for treating municipal sewage has been run for a long term. The selection of the parameters, microorganisms, and the effect factors has been studied. Furthermore many parallel anaerobic-anoxic sequencing batch experiments also have been carried out. Ultimately, mathematical models of phosphorus of two-sludge system are given.Compared with other studies, the innovations of this study are as follows. Firstly, the sludge was cultured and the system was startup successfully in a short term with real sewage, and the operation procedure and controlling conditions for startup were presented. Secondly, for the purpose of avoiding the disadvantage of synthesized wastewater, continuous flow two-sludge system was studied with real sewage. With organic contamination was removed, phosphorus and nitrogen was removed simultaneously. And the optimal parameters of the system were presented. Thirdly the effect factors of denitrifying phosphorus removal were studied, and the concentration change of P and N in the system and the content of PHA and Poly-p in PAO were detected, which can be used to explain the experimentation results logically. Fourthly, the mechanism of denitrifying phosphorus removal and the microbiology of PAO and DNPAO are investigated, and several DNPAOs were isolated successfully. The ability of every isolate was studied respectively.Firstly the ability of simultaneous biological phosphorus and nitrogen removal was investigated in a lab-scale continuous-flow two-sludge system. Alternating anaerobic and anoxic conditions were combined with contact oxidation stage for treating raw municipal wastewater. In the system, nitrifying organisms and denitrifying PAOs (DNPAOs) are circled in the system respectively. DNPAOs circled in anaerobic-anoxic reactors, and nitrifying organisms circled in contact oxidation reactor. In anaerobic reactor, DNPAO uptake substrate in the sewage for PHA synthesization, and at the same time...