废水处理系统中生物聚集体胞外多聚物研究进展

胞外多聚物(Extracellular polymeric substances,EPS)是废水生物处理系统中生物聚集体(包括絮体污泥、生物膜、颗粒污泥等)的重要组成部分,直接包裹于微生物细胞壁外,其理化性质及所处的特殊位置决定了它在生物聚集体中的重要作用.综述了EPS对废水生物处理系统污泥沉降性能、脱水性以及膜生物反应器膜污染影响的相关研究,分析认为EPS组成与结构特性改变污泥表面电位、疏水性等,进而影响污泥沉降与脱水性能、膜污染程度;以好氧颗粒污泥为典型的生物聚集体代表,总结了EPS组分含量与分布对颗粒污泥的形成与结构稳定性的影响,并在EPS提取方法标准化、现代理化技术与分子生物学技术综合分析等方面进行了展望,进一步的研究有望揭示生物絮凝体形成过程EPS的产生与调控机制.

Advances in Extracellular Polymeric Substances of Bio-aggregates in Biological Wastewater Treatment System

Extracellular polymeric substances(EPS) are the key component of bio-aggregates,such as activated sludge,biofilm and granular sludge.They play an important role in the bio-aggregates because of their physic-chemical characteristics and special situation of directly wrapping on the cell wall.The effects of EPS on the settleability and dewaterability of bioaggregates and membrane pollution in membrane bio-reactor(MBR) are reviewed in this paper.It is concluded that the composition and structure of EPS affect the settling and dewatering characteristics of bio-aggregates and the membrane pollution in MBR via changing the sludge surface potential and hydrophobic.At the same time,the role of EPS in the sludge granulation is emphasized that the components and distribution of EPS also influence the formation and structural stability of granular sludge.Finally,the future researches concerning EPS,such as extraction method standardization and incorporation of the physicochemical analysis method and molecular biotechnology,are prospected,showing promise in revealing the EPS production and regulatory mechanism during the formation of bio-aggregates.