| Anaerobic ammonium oxidation (anammox) is a novel nitrogen-removal process,in which ammonium is oxidized anaerobically to N2 by autotrophic bacteria using nitrite as the electron acceptor. Based on analysis of the existing research results on anammox, it was considered that solving the problem of inhition of influent dissolved oxygen was essential to improve anammox bacteria activity and was believed that bio-film reactors utilizing non-woven fabric carriers could form anaerobic condition suitable for anammox bacteria. In this thesis,two bio-film reactors utilizing non-woven fabric carriers with volume of 100mL,2.5L respectively were needed to investigate the effect of influent Ca/P on anammox activity,nitrite inhibition concentration,bio-degradation rule of nitrite and ammonium and rapid start-up of anammox reactor at the temperature of 34～42℃and pH value of 7～8.5. The main results were presented as follows:1. When influent KH2PO4 concentration was 50mg/L,the Ca/P mass ratio of 7 was better for high anammox activity compared to low ratios of 0.5,1 which could cause low ammonium removal rate and nitrite removal rate tend to decline. And the Ca/P mass ratio of 5 was not good for stable long-time nitrite removal.2. The ANAMMOX process was inhibited by nitrite concentration of 98 mg-N·L-1 in the reactor. At the period of anammox activity restoration by decreasing nitrite concentrations,nitrite concentration of 72 mg-N·L-1 caused large-scale drop in nitrite and ammonium removal and when maintaining nitrite concentration of 25～50 mg-N·L-1,it would be possible to reach the same anammox activity as before inhibition.3. There were nearly two different phases in the process of nitrite and ammonium degradation when reactor was performed in the form of batch flow with initial NO2--N/ NH4+-N of 1.3 or so: the increase of degradation velocity and the decrease of degradation velocity. The degradation velocity between 0 to 20min was slower than any other period. The first order exponential decay model could simulate well degradation processes of nitrite and ammonium after 20min. Simulation results demonstrated that degradation velocity of nitrite was always faster than of ammonium. However,the ratio of nitrite and ammonium degradation rate declined with time,which could be explained by the hypothesis that nitrate produced can react with part of ammonium. 4. Influent substrate concentrations and hydraulic retention time affect significantly the volume loading of nitrogen removal. When nitrite concentration was decreased to 5～7 mg-N·L-1,degradation rate of nitrite and ammonium became very slow,thus extending reaction time would reduce reactor's capacity of nitrogen removal. Controlling HRT to make effuluent nitrite reach the values above,the nitrogen removal load with initial nitrite concentration 75 mg-N·L-1,65 mg-N·L-1 was 1.3 more than that with initial nitrite concentration 45 mg-N·L-1,35 mg-N·L-1.5. It took 114 days to reach the highest volume loading of 1.11 kg-N·m-3·d-1 for removal nitrogen when inoculated with nitrifying bacteria in the bio-film reactor utilizing non-woven fabric carriers which could weaken oxygen inhibiton to anammox bacteria. During the process of reactor start-up,anammox activity could be enhanced by a large scale after shutdown at low temperature similar to winter room temperature.
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