【摘要】 以SBR中的活性污泥为研究对象,采用好氧/缺氧运行模式,考察了重金属Pb（Ⅱ）在活性污泥系统中的迁移规律,并结合扫描电镜（SEM）、荧光原位杂交（FISH）等现代分子生物学技术对活性污泥的微观结构及生物相进行表征,解析Pb（Ⅱ）对活性污泥性能的影响及活性污泥对Pb（Ⅱ）的去除机理。结果表明,活性污泥对Pb（Ⅱ）的去除途径主要为生物吸附,且对低浓度（1、5mg/L） Pb（Ⅱ）的吸附效果较好。随着Pb（Ⅱ）暴露浓度的升高,活性污泥的沉降性能逐渐恶化,MLSS逐渐下降,SVI急剧上升,同时系统的脱氮及有机物降解过程受到抑制,NH₄⁺-N、TN及COD去除率显著下降,功能菌群的丰度及多样性降低,氨氧化菌（AOB）和亚硝酸盐氧化菌（NOB）的丰度分别由对照组的13. 72%和17. 61%降至Pb（Ⅱ）浓度为20 mg/L时的2. 41%和7. 11%。此外,活性污泥EPS中的羧基、羟基等负电官能团因其能与Pb（Ⅱ）结合,在Pb（Ⅱ）的吸附去除过程中发挥了重要作用。更多还原

【Abstract】 The migration and transformation of heavy metal Pb （Ⅱ） in activated sludge in a SBR with aerobic/anoxic operation mode was investigated. Microstructure and biological phase of the activated sludge were characterized by scanning electron microscopy （SEM）,fluorescence in situ hybridization （FISH） and other modern molecular biological techniques,and the effect of heavy metal Pb （Ⅱ） on the performance of activated sludge and the mechanism of Pb （Ⅱ） removal by activated sludge were analyzed. The results showed that Pb （Ⅱ） was mainly removed by biosorption and good adsorption effect was achieved at low Pb （Ⅱ） concentrations （1 mg/L and 5 mg/L）. Settleability performance of the activated sludge deteriorated step by step,and MLSS gradually decreased and SVI increased sharply with the continuous increase of Pb （Ⅱ） exposure concentration. Meanwhile,denitrification and organics degradation of the system was inhibited and the removal rates of NH₄⁺-N,TN and COD decreased significantly. The abundance and diversity of functional microbial communities decreased: AOB and NOB decreased from 13. 72% and 17. 61% in the control group to 2. 41% and 7. 11% in the experimental group [20 mg/L of Pb （Ⅱ） ]. In addition,the carboxyl,hydroxyl and other negative functional groups in extracellular polymeric substances of activated sludge played an important role in the adsorption and removal of Pb （Ⅱ） due to their ability to bind to Pb （Ⅱ） .更多还原