N2O Emission and Control in Shortcut Nitrification and Denitrification and Simultaneous Nitrification and Denitrification Biological Nitrogen Removal Systems
污水短程硝化反硝化和同步硝化反硝化生物脱氮中N2O释放量及控制策略

SBR reactors were used to investigate the N2O emission in shortcut nitrification and simultaneous nitrification and denitrification (SND). Shortcut nitrification with nitrosation rate above 90% was realized by real-time control strategy. The N2O emission and variation of nitrosation rate were investigated under 4 DO levels (0.5, 1.0, 1.5, 2.0 mg/L). The results turned out that the optimal DO to maintain high nitrosation rate and minimum N2O emission was 1.5 mg/L and the N2O emission was 0.06 g per ammonium removed. The SBR filled with carbon fiber performed under low DO and pulse feeding. The SND rate was over 79% during the experiment. The N2O emission was studied under DO 0.2, 0.4, 1.0 and 1.5 mg/L. It turned out that the optimal DO was 1.0 mg/L and the N2O emission was 0.021g per ammonium removed. Compared to the shortcut nitrification, the N2O emission of SND was 1/3 of the short-cut nitrification under optimal DO.