| The technology of anaerobic ammonium oxidation (Anammox) is the current most economical microbial nitrogen removal method. It has the advantage of low oxygen demand and low operation cost and without extra carbon source compared with the traditional nitrification and denitrification technology. However, the difficulties of cultivation of Anammox bacteria limited the development of application to full-scale plant. In this paper, the cultivation of Anammox sludge screened from the normal sludge and the restoration of resting Anammox sludge were researched to solve this problem. The influences of substrate concentration, temperature and pH value etc. on the Anammox reactions were also researched in this paper. The kinetic model of the reactions was investigated to instruct the operation of Anammox process. Synthetic wastewater was used in this study.The Anammox bacteria were successfully cultivated from the Anammox sludge, which were screened from the aerobic sludge. During the enrichment of bacteria, it showed that the influent water should be added in batch. The whole enrichment period tooks 60 days. In the reaction system, the highest nitrogen loading was 0.357kgN/(m3·d) and had a stable 92% nitrogen reduction.The research of restoration of the resting Anammox sludge showed that the ability of Anammox reaction could be restored from the well-reserved Anammox sludge in 23 days. During the research of restoration of the resting Anammox sludge, the reactor volumetric loading, sludge loading and concentration of infflent bases influenced the restoration, and they were initially controlled at 0.039KgN/(m3·d), 2.04×10-5KgN/(gMLSS·d) and 150mgNH4+-N/L 180mgNO2--N/L, respectively. At the meantime, the proper amount of media product, hydroxylamine, was added into reactor. This was good to the reaction and accelerated the restoration of Anammox sludge.It was demonstrated that there were some influences of substrate concentration on the Anammox reaction rate. In this paper, the proper reaction temperature were between 30℃and 40℃. The reaction activation energy (Ea) was 68.7KJ/mol. The proper pH value for the Anammox reaction was between 8.0 and 8.5, and the best was 8.0.It was indicated that the Monod mode described the degradation of the ammonia nitrogen. The temperature of 25℃, 30℃, 35℃and 40℃were used to obtain the kinetic parameters. For the ammonia nitrogen degradation, the calculated parameters were Ks =18.23 mg/L and k=16.81 mg/(L·h). For the nitrite degradation, the calculated parameters were Ks=29.95 mg/L and k=22.17 mg/(L·h).This paper made a primary FISH determination for the Anammox bacteria, and provides the important advice for the following research.
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