| The anaerobic ammonium oxidation (Anammox) process, as a novel biological waste water treatment technology on nitrogen removel, has many advantages such as no organics additive as electron donor, no acid&alkali neutralization reagent, no secondary pollution, saving oxygen consumption and low operating cost, thus having a broad prospect of application. Biofilm reactor used for wastewater treatment has a long history. In recent years, its various types have got more research and application. It has many advantages such as convenient operation, less surplus sludge and resistance to shock load.In this study, a set of packed-bed biofilm. reactor using non woven facrics as biomass carrier was established to deal with synthetic waste water. Its nitrogen removal performances and some influence factors including ammonium concentration nitrite concentration and temperature were investigated experimentally. On this basis, the reaction rate equation of anammox reaction was founded.The main contents of the dissertation are as follows:1. In order to reduce the growth of NOB, the temperature was controlled around 33℃, pH value was 7.3, initial HRT was 24 h.20 days later, the ratio between the consumption of nitrite and ammonium was 1.33, and the the ratio between generation of nitrate and the consumption of ammounium was 0.25, close to 1.32 and 0.26 revealed in Anammox reaction function. Anammox reactor was started up successfully.2. The nitrogen loading rate was improved gradually, and long-term stability of the reactor was studied. The reactor was operated for 240 days. During the most operating time, the removal rate of nitrite was above 94.0%, the removal rate of total nitrogen was above 71.9%, HRT was reduced from 24h to 6h and the maximumt nitrogen loading rate could reach to 3.04 kg-N/m3/day. The ratio between consumption of nitrite and ammonium was 1.35, and the ratio between generation of nitrate and the consumption of ammounium was 0.24. The color of the biofilm attached on the non-woven fabrics and the granular sludge at the bottom of the reactor both turned red gradually. The size of the granular sludge increased too.3. By batch tests, the influence of ammonium and nitrite concentration to the anammox activity was studied. The results showed that when the concentration of ammonium was lower than 1000mg-N/l, there was no inhibition to the anammox activity; while the concentration of nitrite was higher than 100 mg-N/1, the activity began to be inhibited. The influences of ammonium and nitrite concentration to anammox reaction were independent and had no affection to each other. The batch tests also showed that when the temperature was increased from 20 to 33℃, the relation between anammox reaction rate and temperature could be described by Arrhenius equation. The anammox reaction had the maximum rate at the temperature of 37℃.4. Considering the inhibition of the nitrite to anammox reaction, the anammox reaction rate equation was established. The Haldane equation involving single substrate inhibition was used as modelling equation. According to experiment data, the equation was fitted, and then the calculated inhibing concentration of nitrite was 100 mg-N/1. The simulation results and experimental results were in good agreement.In conclusion, according to the long-term experiment result of the reactor, the operation parameters and the affecting factors were tested and analysed comprehensively.The optimized operating conditions was determined and the sustrates degradating performances were simulated. Studies in this thesis would provide experimental evidences and theoretical basis for practical application of anammox biofilm reactor and the research of flow-reaction coupling dynamics in the reactor.
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