title: From highly polluted Zn-rich acid mine drainage to non-metallic waters: implementation of a multi-step alkaline passive treatment system to remediate metal pollution.
abstract: Complete metal removal from highly-polluted acid mine drainage was attained by the use of a pilot multi-step passive remediation system. The remediation strategy employed can conceptually be subdivided into a first section where the complete trivalent metal removal was achieved by the employment of a previously tested limestone-based passive remediation technology followed by the use of a novel reactive substrate (caustic magnesia powder dispersed in a wood shavings matrix) obtaining a total divalent metal precipitation. This MgO-step was capable to abate high concentrations of Zn together with Mn, Cd, Co and Ni below the recommended limits for drinking waters. A reactive transport model anticipates that 1 m(3) of MgO-DAS (1 m thick × 1 m(2) section) would be able to treat a flow of 0.5 L/min of a highly acidic water (total acidity of 788 mg/L CaCO(3)) for more than 3 years.
authors: Geology Department, University of Huelva, Campus El Carmen, E-21071 Huelva, Spain. francisco.macias@dgeo.uhu.es
authors: Francisco
authors: F
authors: Macías
authors: Manuel A
authors: MA
authors: Caraballo
authors: Tobias S
authors: TS
authors: Rötting
authors: Rafael
authors: R
authors: Pérez-López
authors: José Miguel
authors: JM
authors: Nieto
authors: Carlos
authors: C
authors: Ayora
mesh_terms: D052918:Environmental Restoration and Remediation / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D008906:Mining; D014874:Water Pollutants, Chemical / Q000032:analysis*; D015032:Zinc / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D015032:Zinc