Separation and recovery of metals from acidic mine waters by ion exchange resins

Mining industry is the major producer of acidic sulphur-rich effluents which often contain elevated concentrations of metals (many of these as sulphide ores of iron, aluminium and manganese primarily among possibly other heavy metals), and metalloids (arsenic, selenium) that pose an additional risk to the environment. The most widespread method used to mitigate acidic effluents is an active treatment involving a chemical-neutralising agent to raise water’s pH, causing the precipitation as hydroxides and carbonates of many of the metals present in solution. This results in the production of an iron and other metals rich sludge. Although chemical treatment can provide effective remediation of acid mine drainage, it has the disadvantages of high operating costs and sludge disposal problems. As prices for several valuable metals (zinc, copper) are increasing over the last years, the main objective of thi project is to separate streams rich in zinc and copper by means of ionic exchange columns from mining effluents and its recovery from solution utilizing electrochemical procedures to balance operating costs from mine water treatment.