title: Removal of aluminum from drinking water treatment sludge using vacuum electrokinetic technology.
abstract: A vacuum electrokinetic apparatus was operated at a municipal water supply plant in Wuxi, China to study the removal of aluminum from the plant's drinking water treatment sludge, high in trivalent aluminum content. The effect of several experimental variables (initial pH, potential gradient, and zone in the sludge tank) and the trivalent aluminum removal mechanism were analyzed. The speciation of trivalent aluminum mainly depends on the initial pH of drinking water treatment sludge, and more fractions of trivalent aluminum were migrated at pH 4 than at higher or lower pH. The application of high voltage can enhance the removal efficiency of aluminum. A three-dimensional electric field analysis explained the difference in the removal efficiency at different zones in the sludge tank. In view of energy consumption, when the initial pH was 4 and a potential gradient of 2 V cm-1was applied, achieving a final aluminum concentration of 30 g kg-1after 120 h. The specific energy consumption was 11.7 kWh kg-1of Al removed.
authors.affiliation: Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China. Electronic address: xuhang810826@163.com.
authors.forename: Hang
authors.initials: H
authors.lastname: Xu
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Mingmei
authors.initials: M
authors.lastname: Ding
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Kunlun
authors.initials: K
authors.lastname: Shen
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Cui
authors.affiliation: Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D002681:China; D060766:Drinking Water; D004563:Electrochemistry; D012722:Sewage / Q000737:chemistry*; D014618:Vacuum; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification
chemical_list: D060766:Drinking Water; D012722:Sewage; D014874:Water Pollutants, Chemical; D000535:Aluminum
keywords: Aluminum; Drinking water treatment sludge; Electric field; Trivalent aluminum speciation; Vacuum electrokinetic