苯酚降低好氧颗粒污泥处理低C/N废水效能的机制探究

Mechanism of Phenol Reducing Aerobic Granular Sludge Performance in Treating Low C/N Wastewater

针对毒性有机物苯酚对好氧颗粒物运行效能影响不明确的现状,在室温条件下探究了不同苯酚浓度对好氧颗粒污泥(AGS)处理低C/N废水的效能的影响,并解析了相关机制。结果表明,苯酚降低了AGS对污染物的去除效能,降低了污泥浓度,导致沉降性下降,并提高了胞外聚合物(EPS)尤其是蛋白质的含量。5.0 mg/L苯酚暴露时,COD、总氮和PO43--P去除效率分别下降至82.6%~84.6%、67.5%~71.6%和80.6%~84.3%,AGS浓度降至4.6 g/L,然而,SVI提高至120~127.5 mL/g,EPS含量提高至81.3~86.5 mg/g。苯酚暴露改变了AGS内微生物群落特征,当苯酚含量为5.0 mg/L时,Proteobacteria、Bacteroidetes和Nitrospirae的相对丰度下降至36.6%、21.3%和5.1%,远低于空白组。本研究结果为AGS处理含苯酚的低C/N废水提供了一定的数据支撑和理论依据。

In view of the unclear influence of toxic organic compound phenol on the operation efficiency of aerobic particles,the efficiency of aerobic granular sludge in treating low C/N wastewater at different phenol concentrations was carried out at room temperature,and the relevant mechanisms were analyzed.The results showed that phenol reduced the removal of pollutants by granular sludge,reduced the concentration of AGS sludge,led to the decline of sedimentation,and increased the content of extracellular polymer(EPS),especially protein.When 5.0 mg/L phenol was exposed,the removal efficiencies of COD,total nitrogen and PO_(4)^(3-)-P decreased to 82.6%~84.6%,67.5%~71.6%and 80.6%~84.3%,respectively,the AGS concentration decreased to 4.6 g/L,SVI increased to 120~127.5 mL/g,and EPS content increased to 81.3~86.5 mg/g.Phenol exposure changed the characteristics of microbial communities in AGS.When the phenol content was 5.0 mg/L,the relative abundance of Proteobateria,Bacteroidetes and Nitrospirae decreased to 36.6%,21.3%and 5.1%,far lower than the blank group.The results of this study provide a certain data support and theoretical basis for AGS to treat low C/N wastewater containing phenol.