Treatment of Percolate from Metal Sulfide Mine Tailings with a Permeable Reactive Barrier of Transformed Red Mud

Abstract

Metal sulfide tailings of the Sardinian (Italy) abandoned Baccu Locci arsenic mine show high concentrations of aluminum, arsenic, cadmium, copper, manganese, lead, and zinc in acid percolate (pH 5 4) and have been classified as ''dangerous waste.'' This paper shows that the release of toxic metals can be strongly reduced when the tailings are placed on a reactive permeable bed (7 wt %) of porous, alkaline pellets of transformed red mud (TRM). During a laboratory percolation test, two columns with 80 kg of waste, of which one contained a bottom layer of TRM pellets, were each alimented with 600 L of de-ionized water. Comparing pH, electroconductivity, metal, and sulfate concentrations of collected percolate from both columns demonstrates efficient neutralization (pH 5 7.4) and removal of metals (80 to 99%) for the column with the permeable reactive bottom layer. Water Environ. Res., 82, 319 (2010).KEYWORDS: acid rock drainage, column leaching, transformed red mud pellet, permeable reactive barrier.

Environmental Toxicity Assessment of the Spilled Ajka Red Mud in Soil Microcosms for Its Potential Utilisation as Soil Ameliorant

“…Some attempts have been made to apply red mud for soil improvement. Red mud has been applied in agriculture for the improvement of acid sulfate soils [18,19]. It is proven to be effective in raising the pH of soils with high organic matter content [20] and low pH [21].…”

Hydrochemical Status of an Acidic Mining Lakein Çan‐Çanakkale, Turkey

“…The results of major ions from the water quality monitoring of Hayırtepe AML are given in Table 2. As seen from the table, sulfate is the predominant anion in all water samples as is the case with many other acidic waters worldwide (Bachmann et al, 2001;Espana et al, 2008;Triantafyllidis and Skarpelis, 2006;Zijlstra et al, 2010). Sulfate levels were observed to be between 4296.68 mg/L and 7275.15 mg/L with a mean value of 5912.51 mg/L.…”

Selenium and Other Trace Element Mobility in Waste Products and Weathered Sediments at Parys Mountain Copper Mine, Anglesey, UK

“…The RMS is a heterogeneous fine fraction residue and contains quartz, Ti-and Al-oxides, pyrite, hematite, goethite and minor elemental S, baryte, galena, and sphalerite, identified by SEM. Deposits of RMS are typical of Al refineries (e.g., Bauxite red muds) but have been known to show affinities for As, Cu, and S mining wastes [38][39][40][41]. Coarser red weathering smelt soils (RWSS) are also typical in Cu mining wasteland areas [39,42,43], produced by weathering of smelt and bedrock.…”