污水深度处理生物滤层中菌群的时空分布特征

Spatial Distributions of Bacteria Populations in A UBAF for Advanced Wastewater Treatment

以生物滤柱为反应器,对污水进行深度处理。试验表明,生物滤层中的菌群由于生化特性的不同,启动阶段异养菌要比自养菌的生长提前一周左右。生物滤柱异养菌、自养菌的形成对稳定运行非常关键,启动阶段较高的COD容积负荷不利于亚硝化、硝化细菌的产生。异养菌在竞争中占有优势,主要生长在滤柱的进水端和悬浮生物膜中。进水有机物浓度较低,造成亚硝化细菌的分布同异养菌分布基本一致。硝化细菌由于较弱的竞争能力,主要生长在滤柱的出水端和吸附生物膜中。底物浓度的改变使生物膜中的菌群对有机物、溶解氧以及生存空间的竞争也发生变化,最终导致其分布也随之改变。

An up-flow biological aerated sewage filter was used for the advanced wastewater treatment.Ammonia-oxidizers follow heterotrophs in the start-up.The UBAF reactor used in this study showed no nitrification when it was started-up with a high COD loading.This inducted the biofilm-formation process is crucial for achieving a multispecies biofilm with heterotrophs and nitrifiers.The inlet area and outer layers of the reactor are dominated more by faster-growing heterotrophs and ammonia-oxidizers with a low COD.The nitrifiers are mostly on the top and outer layers.Experimental observation revealed the non-uniform spatial distributions of bacteria populations within the biofilm because of the competition of the substrate,DO and space.