间歇曝气-内循环生物滤池效能及生物膜特性

针对间歇曝气耦合内循环生物滤池的强化脱氮作用机制尚不明确的问题,探究了反应器沿程污染物去除特性,运用多项测试手段解析系统沿程生物量、生物活性、硝化及反硝化速率,并对反应器内沿程微生物种群特性进行分析.试验结果表明:沿程类蛋白荧光强度逐渐减弱,最终出水并未检测到类蛋白峰;反应器沿程10～50cm区段NH4+-N的降低并没...

Intermittent aeration-internal circulation biological filter performance and biofilm characteristics

The mechanism of enhanced denitrification by intermittent aeration-coupled internal circulation biofiltration is still not clear. We therefore investigated the pollutant removal in a biofiltration reactor. Several methods were used to analyze the biomass, biological activity, and nitrification and denitrification rates of the system, and the microbial population in the reactor was analyzed. The intensity of protein-like fluorescence gradually decreased throughout the system, and no protein-like peak was detected in the effluent. The decrease of NH₄⁺-N along the 10-50cm section of the reactor did not cause a significant increase in NO₃^--N, and the NO₃^--N content decreased at 50cm. This section showed obvious denitrification. The dissolved oxygen and biomass levels throughout the system indicated an anoxic/anaerobic environment and significant denitrification. In addition, the low oxygen uptake rate (OUR) but high TTC-dehydrogenase activity at 50cm and the significantly higher denitrification rate compared to the nitrification rate indicated enhanced denitrification in this region. Based on 16S rRNA high-throughput sequencing analysis, the system had a higher abundance of microorganisms involved in denitrification at the phylum level, mainly Firmicutes (10.64%) and Bacteroidetes (22.29%). Denitrification was also evident at the genus level in Comamonas (3.11%) and Hydrogenophaga (2.43%). Our results suggest that the BAF system with intermittent aeration coupled with internal circulation enhanced denitrification in the bottom zone and thus improved the denitrification efficiency.