Acid Mine Drain (AMD) Treatment to Achieve Very Low Residual Heavy Metal Concentrations

摘要

Mount Emmons mine wastewater treatment plant currently treats on average around450,000 gallons per day of acid mine drain (AMD) water collected into several collectionponds. The plant uses standard lime hydroxide precipitation process at pH 10.7 toprecipitate heavy metals and remove AMD contaminants with the subsequentflocculation - dissolved air flotation (DAF) and sand filtration.Possible opening of the new molybdenum mine at the same site would requirereplacement of the current large DAF and sand filters with the small footprintequivalents. The pilot studies with the small footprint, hybrid centrifugal - dissolved airflotation (GEM System) and walnut filters have been performed. The results of the pilotstudy are described in this manuscript. GEM System and the walnut filters can be usedas a replacement for current technologies.