标题：Coagulation behavior of kaolin-anionic surfactant simulative wastewater by polyaluminum chloride-polymer dual coagulants
作者：Li, Ruihua; Gao, Baoyu; Sun, Jianzhang; Yue, Qinyan
作者机构：[Li, Ruihua; Gao, Baoyu; Sun, Jianzhang; Yue, Qinyan] Shandong Univ, Sch Environm Sci & Engn, Shandong Key Lab Water Pollut Control & Resource, 27 Sha 更多
通讯作者地址：[Gao, BY]Shandong Univ, Sch Environm Sci & Engn, Shandong Key Lab Water Pollut Control & Resource, 27 Shanda South Rd, Jinan 250100, Shandong, Peoples 更多
来源：ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
关键词：Anionic surfactant; Coagulation mechanism; Dual coagulant; Fractal; dimension; Polyacrylamide
摘要：In this study, polyaluminum chloride (PAC) and cationic polymers were used to treat kaolin suspension in the presence of sodium dodecyl benzene sulfonate (SDBS). Effects of PAC dosage, pH, and rotation rate on the coagulation efficiency and floc properties were studied. And the interaction of chemicals and kaolin-SDBS was discussed. Results showed that dual coagulants could decrease the influence of SDBS on the turbidity removal compared with PAC. PAC + polyacrylamide dual coagulant showed superior performance, and the maximal removal ratios of turbidity and dissolved organic carbon were 98.5 and 42.2%, respectively. Optimal coagulation performance was achieved at pH 5-7, where charge neutralization of Al hydrolysates and bridging of polyacrylamide were the primary mechanisms. And flocs with compact structure and small size were formed. Flocs coagulated by PAC were prone to be broken at the pH of raw water after introducing high rotation rate. After dosing polyacrylamide, floc size was enhanced under alkaline condition. Meanwhile, flocs showed stronger recoverability and an open structure because the regeneration mechanism was mainly the bridging effect of polyacrylamide.