• 关键词：胞外聚合物  污泥吸附  动力学模型  污水碳源

• 基金项目：安徽省高校科学研究项目（No.KJ2013A059）

• 胡小兵
• 1. 安徽工业大学建筑工程学院, 马鞍山 243032;2. 生物膜法水质净化及利用技术教育部工程研究中心, 马鞍山 243032

• 叶星
• 安徽工业大学能源与环境学院, 马鞍山 243000

• 周元凯
• 安徽工业大学建筑工程学院, 马鞍山 243032

• 饶强
• 安徽工业大学建筑工程学院, 马鞍山 243032

• 朱荣芳
• 安徽工业大学建筑工程学院, 马鞍山 243032

• 齐小宏
• 安徽工业大学建筑工程学院, 马鞍山 243032

• 钟梅英
• 安徽工业大学建筑工程学院, 马鞍山 243032

• 摘要：为探索活性污泥中不同层胞外聚合物（SB-EPS、LB-EPS和TB-EPS）对污泥吸附性能的影响，以培养污泥、污水厂污泥为研究对象，采用加热法分层提取EPS，研究不同层EPS对生活污水中COD的吸附特征，并采用Lagergern单层吸附动力学模型、Ritchie双层吸附模型和颗粒内扩散模型方程进行动力学数据分析.结果表明：两种污泥的原污泥、-SB污泥和培养-LB污泥与Lagergern单层吸附模型和Ritchie双层吸附模型的拟合效果均比较好，说明污泥吸附过程既存在单层的物理吸附过程，又存在多层的物理化学吸附过程.污泥从外层到内层，EPS含量逐步增加，蛋白质与多糖比值均为外层小于内层，但培养污泥LB-EPS中蛋白质与多糖比值大于TB-EPS.两种污泥单位SB-EPS的吸附量分别为0.650 mg ·mg^-1、3.37 mg·mg^-1，吸附速率比原污泥分别增加了0.0997 min^-1、0.0390 min^-1，因此，SB-EPS可吸附有机污染物，但吸附速率较小.两种污泥单位TB-EPS的吸附量分别为1.06 mg ·mg^-1、0.443 mg ·mg^-1，吸附速率比原污泥分别增加了10.7 min^-1、0.183 min^-1，因此，TB-EPS结构紧密，导致吸附速率减慢，但其能很好地将吸附上的污染物保存在菌体细胞壁外而不被释放.而LB-EPS对污染物没有储存能力，只有快速传递污染物的能力.

• Abstract：To explore the effects of different extracellular polymeric substances (slime-EPS, LB-EPS and TB-EPS) on the adsorption characteristics of the activated sludge, such as cultured sludge and sewage sludge, the organic pollutants (COD) adsorption characteristics of different EPS layers in urban sewage has been investigated through extraction of EPS in different layers after heating. Therefore, three dynamical models have been proposed to understand the adsorption process, including Lagergern's monolayer adsorption kinetics equation, Ritchie's bilayer adsorption kinetics equation, and particle diffusion equation. The results show that the adsorption characteristics of both untreated sludge and-SB(slime bound extracellular polymeric substances) sludge from two sources well conform to the Lagergern's equation and Ritchie's equation, further indicating that both monolayer and bilayer adsorption occurs in the process of sludge adsorption. The content of EPS gradually increases from the outer layer to the inner layer of the activated sludge. The ratio of protein to polysaccharide in the outer layer is smaller than that in the inner layer, however, the ratio of protein to polysaccharide in the outer layer for LB-EPS is higher than that for TB-EPS of cultivated sludge. The adsorbed SB-EPS in the cultivated sludge is 0.650 mg ·mg^-1 and that in the sewage treated plant is as large as 3.37 mg·mg ^-1. Compared to the raw sludge, the adsorption rates increase by 0.0997 min^-1 and 0.0390 min^-1for the above two sludges, respectively. Therefore, it can be concluded that the SB-EPS can absorb organic pollutants with a low adsorption rate. The adsorption capacities of TB-EPS(tightly bound extracellular polymeric substances EPS) for two sludges are 1.06 mg·mg^-1 and 0.443 mg·mg^-1,respectively. The adsorption rates increase by 10.7 min^-1 and 0.183min^-1, respectively, compared to the raw sludge. The compact structure of TB-EPS results in a low adsorption rate, but TB-EPS can absorb the pollutants on the extracellular substances without being released. The LB-EPS cannot store pollutants, but it can deliver pollutants to the inner layer rapidly.

• Key words：extract extracellular polymeric substance  sludge adsorption  dynamics model  carbon in wastewater

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