曝气充氧对城市污染河道水体硝化过程的影响

摘要

[Objective] The study aimed to discuss the effects of aeration on nitrification process in a polluted urban river. [Method] Through indoor simulation experiments, the effects of different aeration conditions ( aerating water named EW , aerating sediments named ES) on nitrification process in a polluted urban river were studied. [ Result ] The nitrification of the control group named EC proceeded slowly, while two kinds of aeration conditions promoted the process of nitrification, that is, the peak values of nitrate nitrogen of EW and ES group were respectively 5. 15 and 3. 83 times that of EC group. Under the two aeration conditions,NO2 - -N accumulation in the overlying water of ES and ES group lasted for 10 and 14 days separately, and the maximum concentrations reached 11.41 and 7. 41 mg/L respectively. Nitrification process was not consistent in the two aeration conditions,that is,the rate of nitrite oxidation in EW group was faster than that of ES group. Denitrificalion process was significant after the aeration, and the concentration of nitric nitrogen in EW and ES group was 1.26 and 2. 82 mg/L respectively at the end of the experiments. [Conclusion] The research could provide scientific references for the restoration of polluted urban rivers.%[目的]研究曝气充氧对城市污染河道水体硝化过程的影响.[方法]通过室内模拟试验,研究不同曝气条件(水曝气Ew、底泥曝气Es)对城市污染河道水体硝化过程的影响.[结果]对照组EG(无曝气措施)底泥硝化进程缓慢,2种曝气条件均促进了硝化过程启动,EW和Es组硝态氮的峰值分别是对照组的5.15和3.83倍；Ew和Es组上覆水中均出现了NO2--N的累积现象,累积天数分别为10、14 d,峰值分别为11.41和7.41 mg/L;2组曝气工况硝化过程进程不一致,Ew组亚硝酸盐氧化速率大于Es组；曝气停止后,反硝化过程明显,试验结束时EW和Es组上覆水中硝态氮浓度分别为1.26、2.82 mg/L.[结论]该研究为城市污染河道水体修复提供了理论参考.