中文摘要：

采用连续流生物膜反应器，通过控制进水DO浓度在2．0mg·L-1、2．5mg·L-1、3．0nag·L-1、3．5mg·L-1、4．0mg·L-1、4．5mg·L-1左右，考察DO浓度对生物膜SND脱氮效果和N2O产量的影响．结果发现，当DO浓度为3．5mg·L-1时，NH4—N去除率在90％以上，TN去除率达到74．32％，生物膜SND效果最佳．DO浓度为3．0mg·L-1时，系统N20产量最大，转化率也最高，约为3．40％左右．从SND脱氮效果、节能降耗和控制N2O产量3方面考虑，将进水DO控制在3．5mg·L-1左右比较合理，既可以达到良好的脱氮效果，又可以减少N2O的产量．

英文摘要：

Continuous flow biofilm reactor were used under different DO concentrations （2.0mg·L-1、2.5mg·L-1、3.0nag·L-1、3.5mg·L-1、4.0mg·L-1、4.5mg·L-1 ） to investigate the effect of nitrogen re- moval on simultaneous nitrification and denitrification （SND） and the nitrous oxide （Na O） emission. The results showed that, when DO were controlled in 3.5 mg·L-1, the NH4＋ -N removal rate was above 90% , TN removal rate was 70. 98% and the effect of nitrogen removal on SND in biofilm reactor was optimal. When DO were con- trolled in 3.0 mg·L-1 , the production of N2O in the system was maximum with the N2Oconversion rate at 3.40%, the highest point. By taking the SND nitrogen removal, energy saving and the control of the production of N2O into consideration, DO should be controlled in 3.5 mg·L-1 a relatively reasonable DO concentration, which could not only achieve better effect of nitrogen removal, but also reduce the production of N2O.