Stefan Steinlechner

Abstract:

In the past, industrial residues were partly recycled in general focusing on the recovery of base metals like zinc, copper, lead or others. Indium, gold, silver and PGMs are accompaniments of lead, zinc or copper ores leading to significant and interesting contents also in the residues arising from the corresponding primary industry, but were not recovered in many cases in the last decades. Because of political unrest, strikes, economic reasons, or decreasing primary resources leading to supply risks also the minor metals, like the mentioned above, moved into the focus of the recycling industry. Therefore, beside the base metals, first of all the recovery of those minor metals would be of high interest contributing to the economic viability of recycling processes, although they occur in much smaller quantities in materials. Examples for such residues can be tailings, sludge, slags and in some cases dusts. The paper shows selected residues, their characteristics, possible treatment to recover next to base metals also selected minor ones and with this especially tries to answer the question on how recycling of such industrial residues can contribute in future to the overall production of for instance precious metals.