摘要
透明胞外聚合颗粒物(transparent exopolymer particles,TEP)是一类主要成分为酸性多糖的高黏性有机微凝胶,普遍存在于海水、淡水和废水中,影响碳元素、微生物和颗粒物等在水环境中的迁移循环.TEP是膜分离系统中一种重要的有机污染物,在过滤过程中附着在膜表面或黏附在膜孔内壁,显著增加膜阻力.研究显示,水环境中的藻类和细菌的种类和生长阶段等因素影响TEP的形成和含量.TEP与膜表面生物膜的形成和早期发育密切相关,是膜生物污染形成的主要成因.颗粒态TEP易在微滤、超滤和反渗透膜表面形成滤饼层,而胶体态TEP和TEP前体易阻塞膜孔或通过超微滤膜孔在反渗透膜表面形成凝胶层.电解质能促进胶体态TEP凝聚形成颗粒态TEP减轻超滤膜污染,同时也能被超滤膜截留去除.絮凝、沉淀、过滤等工艺组合可有效去除TEP,更好地控制膜污染.
Transparent exopolymer particles(TEP)are highly viscous organic microgels and consist predominantly of acidic polysaccharide.TEP are ubiquitous in most source waters,such as sea,surface water,ground water and wastewater,etc.They affect the migration and circulation of carbon,microorganisms and particles in various water environments.TEP have been identified as important organic foulants in membrane systems.They can attach on the membrane surface or on the inner walls of membrane pores during filtration,significantly increasing the membrane resistance.In order to understand membrane fouling induced by TEP in membrane filtration process,the definition,biotic and abiotic formation and determination methods of TEP were introduced,and the membrane fouling mechanisms of TEP were discussed in this paper.The research evidence showed that the species and growth stages of algae and bacteria influenced the formation of TEP which led to serious membrane fouling.It was identified that TEP correlated strongly with the formation and early development of biofilm,which could potentially lead to biofouling.The processes of flocculation,sedimentation and filtration could improve the TEP removal efficiency and substantially reduce TEP-associated fouling.Finally,the further research areas of TEP in membrane separation process were proposed.
作者
刘雅娟
LIU Yajuan(College of Chemistry and Chemical Engineering,Shanxi Datong University,Datong,037009,China;Institute of Carbon Materials Science,Shanxi Datong University,Datong,037009,China)
出处
《环境化学》
CAS
CSCD
北大核心
2020年第11期3038-3049,共12页
Environmental Chemistry
基金
山西省回国留学人员科研资助项目(2017-108)
大同市科技计划项目(2018020)资助
