Evaluation of activated sludge properties’changes in industrial-wastewater pre-treatment:role of residual aluminum hydrolyzed species with different polymerization degree  

作　　者：Ziqi Zhao Meng Li Wansong Huang Nuowei Guo Qian Zhang 

机构地区：[1]School of Civil Engineering and Architecture,Wuhan University of Technology,Wuhan 430070,China [2]Hubei Jianke International Construction Ltd.Co,Wuhan 430070,China [3]Wuhan Hanyang Municipal Construction Group Co.Ltd.,Wuhan 430000,China [4]Shenzhen Research Institute of Wuhan University of Technology,Shenzhen 518000,China

出　　处：《Frontiers of Environmental Science & Engineering》2023年第6期141-151,共11页环境科学与工程前沿（英文）

基　　金：The authors disclosed receipt of the following financial support for the research,authorship,and/or publication of this article:This work was supported by the Hubei Provincial Key Laboratory of Water System Science for Sponge City Construction(No.2019-06);the Science and Technology Program of Shenzhen(No.JCYJ20210324122602006).

摘　　要：With the widespread introduction of pre-coagulation prior to the biological unit in various industrial wastewater treatments,it is noteworthy that long-term accumulation of residual coagulants has certains effect on both micro and macro characteristics of activated sludge(AS).In this study,the morphology distributions of residual aluminum salts(RAS)and their effects on the removal efficiency of AS were investigated under different PAC concentrations.The results showed that the dominance of medium polymeric RAS,formed under an appropriate PAC dose of 20 mg/L enhanced the hydrophobicity,flocculation,and sedimentation performances of AS,as well as the enzymatic activity in cells in the sludge system,improving the main pollutants removal efficiency of the treatment system.Comparatively the species composition with monomer and dimer/high polymer RAS as the overwhelming parts under an over-dosed PAC concentration of 55 mg/L resulted in excessive secretion of EPS with loose flocs structure and conspicuous inhibition of cellular activity,leading to the deterioration of physico-chemical and biological properties of AS.Based on these findings,this study can shed light on the role of the RAS hydrolyzed species distributions,closely relevant to Al dosage,in affecting the comprehensive properties of AS and provide a theoretical reference for coagulants dosage precise control in the pretreatment of industrial wastewater.

关 键 词：Coagulation/flocculation Hydroxyl-aluminum Hydrolysis reaction Reactor performance Activated sludge property Surface properties 

分 类 号：X703[环境科学与工程—环境工程]