Improving sludge dewaterability via Fe^(2+) chelated citrate activated peroxydisulfate oxidation  

作　　者：Donghai Yuan Xinyu Li Siyu Xiong Jun Cui Jijiao Zhou Yingying Kou 

机构地区：[1]Key Laboratory of Urban Stormwater System and Water Environment,Ministry of Education,Beijing University of Civil Engineering and Architecture,Beijing 100044,China [2]Department of Environmental Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,China [3]Huzhou Environmental Sanitation Management Center,Huzhou 313000,China

出　　处：《Journal of Environmental Sciences》2023年第3期223-233,共11页环境科学学报（英文版）

基　　金：supported by the National Water Pollution Control and Management Technology Major Project (No. 2018ZX07110005);the National Natural Science Foundation of China (No. 52170097);the Fundamental Research Funds for Beijing University of Civil Engineering and Architecture (Nos. X18288, X18289 and X20137)。

摘　　要：Citrate (Ct) was chosen as a typical chelator used in the Fe^(2+)-peroxydisulfate (PDS) process to improve sludge dewaterability.The PDS-Fe^(2+)-Ct process exhibited better performance in sludge dewatering than PDS-Fe^(2+).Specifically,with a PDS dosage of 1.2 mmol/g VS,the molar ratio of PDS/Fe^(2+)and Ct/Fe^(2+)were 4:5 and 1:4,respectively,the capillary suction time decreased from 155.8 to 24.8sec,and the sludge cake water content decreased from 82.62%to 64.11%(-0.06MPa).The oxidation led to a reduced negative charge and a decrease in particle size.The enhanced sludge dewaterability and changes of sludge properties were attributed to the decomposition of extracellular polymeric substances,and it was explored by protein,polysaccharide,3D-EEMs,and FT-IR.Additionally,the quenching experiments of radical species demonstrated that SO_(4)-·played a more important role than·OH,and its productivity was improved with the addition of Ct.Moreover,the reasons for the improved productivity of radicals with the addition of Ct were discussed.The results of this study could serve as a basis for improving sludge dewatering using the PDS-Fe^(2+)-Ct process and suggest that the addition of Ct may improve the productivity of SO_(4)-·in the activation o PDS via Fe^(2+).

关 键 词：Wastewater sludge DEWATERABILITY Peroxydisulfate oxidation CITRATE 

分 类 号：X703[环境科学与工程—环境工程]