不同氨氮浓度对部分亚硝化过程中N_2O释放的影响

目的]研究氨氮浓度对部分亚硝化过程中温室气体N2O释放的影响。方法]利用序批式生物膜反应器(SBBR),采用间歇曝气的方式,分析进水不同氨氮浓度对部分亚硝化过程中N2O产生的影响。结果]当进水氨氮浓度不同时,部分亚硝化过程中DO、ORP变化趋势大体一致,出水中亚硝氮与氨氮的浓度比都能达到1∶1,而且硝氮始终都维持在较低水平。进水氨氮浓度对部分亚硝化过程中N2O的释放有显著影响,氨氮浓度越高,N2O的释放量越大。其中,当氨氮浓度为400 mg/L时,N2O的释放量高达37 mg左右。结论]部分亚硝化过程中N2O的释放可能与NH4+、NO2-的浓度有关。

Effects of Different Concentrations of Ammonia Nitrogen on N2O Emission in the Process of Partial Nitrification

Objective] The study aimed to discuss the effects of different concentrations of ammonia nitrogen on N2O emission in the process of partial nitrification.Method] By using a sequencing batch biofilm reactor(SBBR) under intermittent aeration,the influences of various concentrations of influent ammonia nitrogen on nitrous oxide(N2O) emission from partial nitrification were analyzed.Result] When the concentration of influent ammonia nitrogen varied from 200 to 400 mg/L,the changing trends of DO and ORP value were consistent during the process of partial nitrification,and the concentration ratio of NO-2-N to NH+4-N in the effluent reached 1∶1,with lower NO-3-N level.In addition,ammonia nitrogen concentration in the influent had a significant effect on N2O emission in the process of partial nitrification,that is,the higher the ammonia nitrogen concentration,the more the N2O emission.When ammonia nitrogen concentration was 400 mg/L,N2O emission was up to about 37 mg.Conclusion] N2O emission in the process of partial nitrification might be related to the concentration of NH+4 and NO-2.