Heavy metals removal from Acid Mine Drainage by innovative technologies

Main aim of the experimental work was to apply innovative technologies, such as electrowinning and bioprecipitation, to remove heavy metals from Italian Acid Mine Drainage (AMD) samples. The experimental activity carried out during the investigation was aimed to decrease the heavy metals content and has been conducted by synthetic solutions. A cylindrical glass laboratory cell of 200 cm3 volume has been used for electrowinning tests, while bioprecipitation tests have been performed in two interconnected reactors with a volume 250 cm3. By electrowinning process, it was possible to achieve over 90 % metals removal. A high grade of purity of the metal deposit has been achieved (about 95 %), while bioprecipitation permitted only the Cd elimination. On the basis of the experimental results achieved, the processes at laboratory scale will be optimised.