活性污泥快速实现短程硝化及稳定高效运行

Rapid Realization of Shortcut Nitrification and Its Stable and Efficient Operation

为了实现快速有效的短程硝化控制和高硝化速率,采用A2O工艺的活性污泥,利用CSTR反应器,分别控制游离氨和溶解氧浓度,对硝化活性污泥快速实现短程硝化及稳定高效运行进行研究。在低游离氨浓度控制体系中,对硝态氮的产生不具有很好的控制作用,短程硝化难以启动;在高游离氨浓度控制体系中,实现了5 d快速启动短程硝化,亚硝态氮积累率稳定在90%以上;提高短程硝化过程的溶解氧浓度,硝化性能从26 mg/(L·h)增长到54 mg/(L·h),亚硝态氮积累率仍稳定维持在90%以上,达到高效稳定运行的目的;另外,从AOB生长动力学分析可知,提高游离氨浓度对提高AOB生长速率具有非常重要的意义。因此,通过控制高游离氨浓度、提高溶解氧可以快速实现短程硝化并稳定高效运行。

In order to achieve quick and effective shortcut nitrification and high nitrifying rate, study on the rapid realization of shortcut nitrification and its stable and efficient operation in Continuous Stirring Tank Reactor （CSTR） using A20 activated sludge as seed sludge was conducted. In the process, free ammonia and dissolved oxygen concentration were controlled, respectively. The experiment results showed that high free ammonia and dissolved oxygen concentration could quickly realize shortcut nitrifica- tion and stable and efficient operation. Nitrate nitrogen could not be suppressed effectively under the con- dition of low free ammonia and it was hard to start shortcut nitrification; however, rapid start-up of short- cut nitrification could be achieved for five days under the condition of high free ammonia, and the nitrite nitrogen accumulation rate stability remained above 90% ; high dissolved oxygen concentration greatly in- creased nitrification capability from 26 mg/（ L · h） to 54 mg/（ L · h）, at the same time nitrite nitrogen accumulation rate still remained above 90%. In addition, from the AOB growth dynamics analysis, the same conclusion that increasing free ammonia concentration was very important to AOB growth rate could be obtained.