Recovery and reuse of sludge from active and passive treatment of mine drainage-impacted waters: a review

Abstract

The treatment of mine drainage-impacted waters generates considerable amounts of sludge, which raises several concerns, such as storage and disposal, stability, and potential social and environmental impacts. To alleviate the storage and management costs, as well as to give the mine sludge a second life, recovery and reuse have recently become interesting options. In this review, different recovery and reuse options of sludge originating from active and passive treatment of mine drainage are identified and thoroughly discussed, based on available laboratory and field studies. The most valuable products presently recovered from the mine sludge are the iron oxy-hydroxides (ochre). Other by-products include metals, elemental sulfur, and calcium carbonate. Mine sludge reuse includes the removal of contaminants, such as As, P, dye, and rare earth elements. Mine sludge can also be reused as stabilizer for contaminated soil, as fertilizer in agriculture/horticulture, as substitute material in construction, as cover over tailings for acid mine drainage prevention and control, as material to sequester carbon dioxide, and in cement and pigment industries. The review also stresses out some of the current challenges and research needs. Finally, in order to move forward, studies are needed to better estimate the contribution of sludge recovery/reuse to the overall costs of mine water treatment.

Experimental Study of Moisture Content Effect on Geotechnical Properties of Solidified Municipal Sludge

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Combination of Iron Chloride and Polyacrylamide as Coagulant-Flocculants to Remove Pollutants in Dye Wastewater

“…Despite the treatment of wastewater, the process of identifying pollutants in the sludge after treatment is crucial for environmentalists to prevent the production of pollutants from industries. Sludge formed after wastewater treatment processes was investigated in previous studies as stabilizer for contaminated soil, as substitute material in construction, as fertilizer in agriculture/horticulture and others potential aspects [7]. The application of sludge waste is recommended as an alternative for soil fertilization.…”

Effect of Temperature on Phase Transformation and Leaching Behavior of Acid Mine Drainage Sludge

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