Study On Shortcut Denitrifying Phosphorus Removal With CAMBR Treating The Domestic Wastewater

The process of biological nitrogen and phosphorus removal need easily degradable enough carbon source. Thus, the study integrated shortcut nitrification with shortcut combination of denitrifying phosphorus removal, to improve the utilization rate of carbon source. Therefore, a combined process of anaerobic baffled reactor?ABR? with microbial phase separation and membrane bioreator?MBR?, i.e. CAMBR was combined. The volatile fatty acids?VFAs? are the high quality carbon source which can be utilized in the process of denitrifying phosphorus removal. And the ABR anaerobic hydrolysis acidification provided VFA,with high efficiency and low energy consumption of domestic waste water. The main results of this thesis were as following:?1? Firstly Cultivating denitrifying dephosphatation bacteria become system advantage strains in the process of CAMBR reactor start-up, then gradually make denitrifying dephosphatation bacteria and utilize nitrite as electron acceptor. Under the condition of HRT 12 h, the influent organic load of CAMBR was 1.2kg?m³·d?^-1, anoxic phosphorus uptake was about 10mg·L^-1, p H at 8.0?8.3, DO at 0.8? 1.5mg·L^-1,aerobic phosphorus uptake was about 1mg·L^-1, and denitrifying phosphorus removal was above90%. The phosphorus was mainly removed by anaerobic denitrifying phosphorus removal which suggests that denitrifying phosphorus removal bacteria under anoxic condition has become a superiority strains in the system. The system has realized short-cut denitrifying dephosphatation. Under the condition of HRT 12 h, the influent organic load of CAMBR was 1.2kg?m³·d?^-1,the mud mixture back into 1.2 h of the system, the reflux ratio is 100%. Hydrolytic acidification of organic matter was used denitrifying phosphorus removal. The average effluent concentration of COD, NH₄⁺-N, TN, soluble phosphate concentration were 28mg·L^-1 ?1.5mg·L^-1 ?9.3mg·L^-1 and 1.22mg·L^-1 respectively. The ultimate average removal efficiency of COD, TN and soluble PO43--P were 92%? 96% ?80% and 93%. The stable and efficient short-cut denitrifying dephosphatation was achieved in the CAMBR.?2? The influent organic load of the system was 1.8 kg?m³·d?^-1with the optimal ABR HRT of 4.8 h, the mud mixture back into 1.2 h of the system, the reflux ratio is 100%. The CAMBR system has realized the effective phase separation of anaerobic phosphorus release, anoxic denitrification and dephosphorization, aerobic shortcut nitrification denitrification and phosphorus absorption. The amount of the high-quality carbon source?VFA? of the ABR anaerobic hydrolysis acidification was 56.1 mg·L^-1, which was used to synthetise PHB in the cells. The release of phosphorus was 10.43 mg·L^-1, showing that5.38 mg of VFA were required to release 1mg PO43--P. Meanwhile, the uptake of phosphorus was 12.35mg·L^-1, while the uptake of phosphorus of MBR tank was1.33mg·L^-1. In the process of shortcut nitrification, 0.62 mg NOx--N was needed when 1mg PO43--P was uptaken, and 1.67 to 2.04 mg NO2--N was required when 1mg PO43--P was uptaken.?3? Under the optimum operation condition(the influent organic load of 1.8 kg?m³·d?^-1, HRT of ABR 4.8 h, the mud mixture back into 1.2 h of the system, the reflux ratio is100%.), the CAMBR achieved stable and high efficient denitrifying phosphorus removal on domestic sewage treatment and the ultimate average removal efficiency of COD, TN and soluble PO43--P were 91%, 84% and 93%, respectively, accordingly the average effluent concentrations were 30, 7.15 and 0.55 mg·L^-1.?4? When CAMBR short-cut denitrifying phosphorus removal treated sewage.through optimizing the operating conditions, the low consumption of organic removal can be realized in the ABR, and enough high quality carbon source can be provided for denitrifying phosphorus removal.