The amelioration of acid mine drainage by anin situ electrochemical method—I. Employing scrap iron as the sacrificial anode Original Research Article

The project began in an attempt to develop technology to ameliorate acid mine drainage (AMD) problems occurring at the Sherman Iron Ore Mine of Temagami, Ontario, Canada. A series of laboratory experiments were conducted to evaluate the effectiveness of an electrochemical approach to ameliorate AMD. An electrochemical cell was constructed using a block of massive sulphide-graphite rock from the mine site as the cathode, scrap iron as the sacrificial anode, and acidic leachate collected from the mine site as the electrolyte. The cell was effective at raising the pH of ≈ 41.0 L of leachate from 3.0 to a maintenance value of ≈ 5.6. This result was accompanied by a significant decrease in redox potential from > 650 to < 300 mV. Furthermore, iron sulphate precipitate formed, with a concomitant lowering of Al, Cd, Co, Cu and Ni solution concentrations. The study clearly demonstrated the proposed electrochemical approach to be a technically feasible and practical method of ameliorating AMD.