Potential for water and metal recovery from acid mine drainage by combining hybrid membrane processes with selective metal precipitation

• Published in: Resources, conservation and recycling conservation and recycling, 2023-01, Vol.188, p.106629, Article 106629
• Main Authors: León-Venegas, Elena, Vilches-Arenas, Luis F., Fernández-Baco, Custodia, Arroyo-Torralvo, Fátima
• Format: Article
• Language: English
• Subjects: Acid mine drainage; Forward osmosis; Iberian Pyrite Belt; Osmotically assisted reverse osmosis; Selective metal precipitation; Water and metal recovery
• ISSN: 0921-3449; 1879-0658
• DOI: 10.1016/j.resconrec.2022.106629

Acid mining drainage has a serious impact on the environment. Forward osmosis allows the concentration of acid mine waters to favor the formation of enrichment sludges and subsequent selective metal precipitation. In this work, a methodology was proposed to treat mining effluents from the Iberian Pyrite Belt. Forward osmosis experiments were performed using different osmotic pressures from 0.5M to 2.5M NaCl to evaluate water fluxes and recovery. The water recovery obtained was in the range of 50-80%, and the flux remained above 5 (L•m−2•h−1). Four combined processes were modelled to determine the feasibility of eliminating water and precipitating metals. Furthermore, a new hybrid membrane process was proposed to recover at least 75% of water with recovery yields of Al, Fe, Cu, Zn and Mn of greater than 70%. A water production cost of 2.01 $/m3 and a specific energy consumption of 8.03 kWhe/m3 were estimated for the hybrid process. Graphical Abstract [Display omitted] .