ITFB强化除氨及醌指纹生物群落结构分析

通过改变内循环生物流化床(internal-circulation three-phase bio-fluidized bed,ITFB)的启动水质,提高N/C组成以强化流化床后期的硝化作用.结果表明,高N/C和低进水COD是强化除氨的必要启动条件;强化启动后以模拟生活污水为研究对象,在HRT为2h时,可以实现COD和氨氮的同时高效去除,氨氮的平均去除率为74%,出水氨氮浓度小于10 m g/L.研究利用醌指纹技术对反应系统中微生物群落结构变化进行了跟踪分析,结果表明经过强化除氨启动后,内循环生物流化床生物膜中以Nitrosomonas europaea为代表的硝化细菌数量有所增加;而以Acinetobacter sp.和Pseudomonas sp.为代表的变形细菌的γ亚类数量减少.EQ值始终在0.5左右变化表明生物膜中微生物种群的分布均匀性变化较小.所有测试样品中UQ/MK的比值均大于1,说明生物膜系统中以革兰氏阴性菌为主.

Enhanced Ammonia Removal and Microbial Community Structure Analysis Using Bacterial Quinone Profile in ITFB

Water quality during the start-up period was changed in order to enhance the later nitrifying ability of the internal-circulation three-phase bio-fluidized bed (ITFB). The experimental results showed that high N/C ratio and low feeding concentration of COD were two key conditions for enhancing the ammonia removal. After the enhanced start-up, an efficient removal efficiency of both COD and ammonia was achieved with HRT 2h when treating sanitary wastewater, the average ammonia removal rate was 74% , the ammonia concentration in effluent was lower than 10 mg/L. Bacterial quinone profile of the system was also analyzed. The results showed that after the enhanced start-up, the number of nitrifying bacteria, such as Nitrosomonas europaea, in the biofilm in ITFB was increased, and the number of gamma-Proteobacteria, such as Acinetobacter sp. and Pseudomonas sp., was decreased. the equitability of the quinones (EQ) fluctuated around 0.5 showed that the distribution of the microbial community in the biofilm changed little. UQ/MK ratio of all the samples was greater than 1 indicated that Gram-negative bacteria was the dominant bacteria in the system.