Efficient Treatment of the Sweet Potato Starch Wastewater by Enhanced Flocculation–Coagulation of Environmentally Benign Materials

作     者：Zhang, Yalan Li, Meng Zhang, Guihai Liu, Wei Xu, Jinying Tian, Yuansong Wang, Yinfeng Xie, Xingyue Peng, Zhiqi Li, Aimin Zhang, Ru Wu, Daishe Xie, Xianchuan 

作者机构：Key Laboratory of Poyang Lake Environment and Resource Utilization Ministry of Education School of Resource and Environment Nanchang University Nanchang330031 China State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing210023 China Wireline Product Operation ZTE Corporation Nanjing210023 China Nanjing University Yancheng Academy of Environment Protection Technology and Engineering Nanjing210023 China Jiangxi Nanxin Environmental Protection Technology Co. LTD Jiujiang City of Jiangxi Province 330300 China School of Materials and Chemical Engineering Pingxiang University Pingxiang337000 China 

出 版 物：《SSRN》 

年 卷 期：2022年

核心收录：

主　　题：Flocculation 

摘      要：Sweet potato starch wastewater from rural areas of China is in urgent need of a new efficient and environmental-friendly method for proper treatment, because it contains high-concentration organic pollutants, with a great impact on water quality, and also most of it is treated in a distributed manner. In this study, bentonite was selected from four kinds of clay minerals (i.e. kaolin, zeolite, attapulgite and bentonite) as coagulant aids, and chitosan-modified bentonite combined with polyglutamic acid was used for enhanced coagulation treatment for starch wastewater. Among them, bentonite can adsorb soluble pollutants in starch wastewater, chitosan modification can enhance the coagulation effect, and the flocculant of polyglutamic acid is conducive to the removal of particulate matter through bridging effects. The combination of the three can effectively and deeply remove pollutants in starch wastewater. Under the optimal conditions, the removal rates of chemical oxygen demand , total nitrogen, total phosphorus and turbidity can reach 86.2%, 80.3%, 52.3% and 98.2%, respectively, which are far higher than that of the vast majority of coagulants currently reported. Density functional theory calculation has showed that the electrostatic potential around aluminum in bentonite of 14.248 *** -1 is more conducive to the adsorption of negatively charged organic pollutants, and that bentonite has lower adsorption energy ( -1.43 eV) than chitosan and polyglutamic acid, thereby resulting in higher adsorption affinity of bentonite. Mechanistic studies confirmed that the coagulation mechanism includes electrical neutralization and the promotion of efficient collision of clay particles to form flocs . © 2022, The Authors. All rights reserved.