title: Iron-Anode Enhanced Sand Filter for Arsenic Removal from Tube Well Water.
abstract: Sand filters are widely used for well water purification in endemic arsenicosis areas, but arsenic (As) removal is difficult at low intrinsic iron concentrations. This work developed an enhanced sand filter by electrochemically generated Fe(II) from an iron anode. The efficiency of As removal was tested in an arsenic burdened region in the Jianghan Plain, central China. By controlling a current of 0.6 A and a flow rate of about 12 L/h, the filter removed total As in the tube well water from 196 to 472 μg/L to below 10 μg/L, whereas the residual As was about 110 μg/L without electricity. Adsorption and subsequent oxidation on the surface of Fe(III) precipitates are the main processes controlling the removals of As and Fe. During a 30-day intermittent operation, both effluent As concentration and electrical energy consumption decreased progressively. Although filter clogging was observed, it can be alleviated by replacing the top layer of sand. Our findings suggest that dosing Fe(II) by an iron anode is an effective means to enhance As removal in a sand filter.
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences , 388 Lumo Road, Wuhan 430074, P. R. China.
authors.forename: Shiwei
authors.initials: S
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences , 388 Lumo Road, Wuhan 430074, P. R. China.
authors.forename: Songhu
authors.identifier: 0000-0001-6119-1646
authors.initials: S
authors.lastname: Yuan
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences , 388 Lumo Road, Wuhan 430074, P. R. China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liao
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences , 388 Lumo Road, Wuhan 430074, P. R. China.|School of Environmental Studies, China University of Geosciences , Wuhan, Hubei 430074, P. R. China.
authors.forename: Man
authors.initials: M
authors.lastname: Tong
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences , 388 Lumo Road, Wuhan 430074, P. R. China.|School of Environmental Studies, China University of Geosciences , Wuhan, Hubei 430074, P. R. China.
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Gan
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences , 388 Lumo Road, Wuhan 430074, P. R. China.|School of Environmental Studies, China University of Geosciences , Wuhan, Hubei 430074, P. R. China.
authors.forename: Yanxin
authors.initials: Y
authors.lastname: Wang
mesh_terms: D001151:Arsenic; D004566:Electrodes; D005374:Filtration; D007501:Iron; D014867:Water; D014874:Water Pollutants, Chemical; D018508:Water Purification
chemical_list: D014874:Water Pollutants, Chemical; D014867:Water; D007501:Iron; D001151:Arsenic