上向流曝气生物滤池中有机氮沿程转化规律与生物特性研究

Regularity of organic nitrogen transformation and biological characteristics along up-flow biological aerated filter reactor

为揭示上向流曝气生物滤池中有机氮沿程转化规律及其微生物特性,优化滤池的设计与运行,以有机氮废水为处理对象,在水力负荷0.329～0.505m3/(m2·h)、气水比4-5:1、沿程DO3.0～5.85mg/L、不加任何有机碳源的情况下,研究氮元素沿程转化规律。结果表明:曝气生物滤池内有机氮氨化与硝化同步进行,90%以上的溶解性有机氮(DON)转化为NO3-N;滤池沿程各段对于TKN的降解进程(TKN→NH3-N)与NH3-N的硝化进程(NH3-N→NO2--N→NO3--N)一致;微生物总量沿水流方向呈逐渐递减趋势;生物耗氧速率(OUR)沿程逐渐减小,OUR数量级为101mg/(g·h)。该研究可为硝化滤池的设计提供理论依据以及滤池运行参数的优化提供技术支持。

In order to study the characteristics of microbe and organic nitrogen transformation along the reactor of Up-flow Biological Aerated Filter（BAF） and optimize the design and work of the filter with the sewage containing organic nitrogen. Five sampling ports should be set along the reactor. And at 0.329-0.505 m^3/（m^2 · h） of hydraulic loading, （4-5） ： 1 of the air/water ratio, 3.0-5.8 mg/L along the reactor of DO with no organic carbon. The results showed that simultaneous nitrification and ammonization were the major process in the reactor. More than 90% DON was transformed into NO3^--N. The ammonization rate was obviously faster than nitrification rate among 0-0.29 of the relative attitude of the filter, however, both nitrification and ammonization rate were declined and tend to balance finally as the height of filter media raised. There was few NO2^--N left along reactor. It was found that the biomass of each segment decreased from the bottom to the top of the reactor. Each segment along reactor could form steady micro-ecosystem. A decreasing trend of OUR was observed at the order of 10^1 mgO2/（g·h） in the BAF reactor. The study can provide theoretic basis for the design of the reactor and technique for the optimization of working parameters.