The Characteristics Of Partial Nitrification In SBR And The Start-Up Of Anammox

The Nitration-Anammox process is a new method for ammonia removal from wastewater, which includes two steps. In the partial nitrification process, ammonium is first partially oxidized to nitrite under the anoxic conditions and in the anammox process; ammonium is oxidized to dinireogen gas by particular microorganisms with nitrite as the electron acceptor under the anaerobic condition to realize the denitrification. SHARON (Single reactor High activity Ammonia Removal Over Nitrite)and OLAND(Oxygen Limited Autotrophic Nitrification Denitrification) are the most famous processes of nitration, which usually use CSTR (Continuously Stirred Tank Reactor)and MBR (Membrane BioReactor) as reactor respectively. But in this research SBR is used as autotrophic partial nitrification reactor. The long-time run of the nitration process and the performances were studied, and the results and parameters were analyzed.Inoculated with nitrifying activated sludge, autotrophic partial nitrification was rapidly started-up in a SBR under moderate temperature(30℃), high free ammonia and low DO. The system was operated stably for 114 cycles at reaction time: 6.0 h, aeration rate: 800 ml/min. The NH₄⁺-N removal efficiency and NO₂^--N accumulation ratio could reach 83.6% and 97.2%, respectively. NO3--N concentration was as low as 5.62 mg/l in each cycle on average. In batch experiments the influence of aeration rate, COD, alkalinity, temperature and NH₄⁺-N loading on SBR were also discussed. At the base of above, two kinds of method to achieve half-nitration were studied in detail: DO control and alkalinity control. The results and relative rules we got had the academic and technical significances on the treatment of municipal sewage.The ANAMMOX (ANaerobic AMMonium OXidation, ANAMMOX) was started in gas-lift reactor. The initial concentrations of NH₄⁺-N and NO₂^--N were almost 50 mg/L. In the first 40 days, the NO₂^--N/NH₄⁺-N system consumed was within 1.0 to 1.5, which is similar to other researchers'results. But after 60 days the system was gradually broken down. Although the start-up was failed, the experience of it was concluded to direct the experiments afterward.