PRESENT STATUS IN THE RECYCLING OF INDUSTRIAL RESIDUES FROM LEAD, ZINC AND COPPER INDUSTRY AND THEIR POSSIBLE FUTURE CONTRIBUTION TO THE SUPPLY OF SELECTED MINOR ELEMENTS, LIKE SILVER

In the past the treatment of industrial residues from copper, lead or zinc industry focused in the majority of cases only on the recovery of one target metal. Mostly it is the focal metal produced in the industry the residue arises from. With this, valuable accompanying elements were often disregarded. Especially in copper, zinc and lead industry minor metals, like the group of precious metals but also others like indium or germanium, are interesting side-elements occurring in the concentrates next to the base metal itself. Although a recovery of these elements is partly considered in the base metal production, the presence in the corresponding residues in regard to their recycling is unvalued in a lot of processes until today. This offers the chance in future recycling concepts that these minor elements, like for instance silver, can contribute to the overall economic feasibility of potential new processes, even though they occur in significant lower amount as the base metal in the tailings, dusts, sludge or dusts of the corresponding industry. For example the annually produced and mainly land filled amount of leach residues from zinc industry contains roughly 500 tons silver next to other valuable elements, like zinc or lead. Thus, this paper tries to answer the question how recycling of such residues can contribute to the supply of minor elements, especially at the example of silver.