Characterization and Processing of Residues …
445
Including landfilling, the overall revenue of 390 USD per ton of residue can be
calculated. Due to current metal prices, silver is of main importance. In all the calculations, the metal yield of the process has not been considered. Taking about 90%
into consideration, the value is reduced to 350 USD per ton. This would allow an
economic treatment using the described pyrometallurgical process. However, there
are of course dumps with lower amounts of valuable elements. In this case, a beneficiation would help to reduce energy costs and allow an economic processing also
with lower metal concentrations. Gold could play an important role. If only 2 ppm
is collected, additional 100 USD can be added to the revenue.
Summary
Zinc leach residues, often called jarosite, are dumped worldwide. University of
Leoben together with industry has developed a process for the recovery of valuable
metals. The process has been tested and up-scaled. Furthermore, detailed characterization has been carried out for different dumpsites. To allow better economic conditions by saving energy, the first tests for possible beneficiation have been performed.
Only for some residues, a concentration of valuables was possible. Economics
showed positive values for metal rich leach residue types while for lower metal,
especially lower silver concentrations, a concentration by flotation is mandatory.
References
1. Reuter MA, UNEP (2013) Metal recycling: opportunities, limits, infrastructure, international
resource panel
2. Patino F, Salinas E, Cruells M, Roca A (1998) Alkaline decomposition–cyanidation kinetics of
argentian natrojarosite. Hydrometallurgy 49:323–336
3. Hanke G, Melcher F, Antrekowitsch J (2016) Characterisation of by-products of the zinc industry.
In: OPMR 2016 Opportunities in processing of metal resources in South East Europe, pp 184–190
445
Including landfilling, the overall revenue of 390 USD per ton of residue can be
calculated. Due to current metal prices, silver is of main importance. In all the calculations, the metal yield of the process has not been considered. Taking about 90%
into consideration, the value is reduced to 350 USD per ton. This would allow an
economic treatment using the described pyrometallurgical process. However, there
are of course dumps with lower amounts of valuable elements. In this case, a beneficiation would help to reduce energy costs and allow an economic processing also
with lower metal concentrations. Gold could play an important role. If only 2 ppm
is collected, additional 100 USD can be added to the revenue.
Summary
Zinc leach residues, often called jarosite, are dumped worldwide. University of
Leoben together with industry has developed a process for the recovery of valuable
metals. The process has been tested and up-scaled. Furthermore, detailed characterization has been carried out for different dumpsites. To allow better economic conditions by saving energy, the first tests for possible beneficiation have been performed.
Only for some residues, a concentration of valuables was possible. Economics
showed positive values for metal rich leach residue types while for lower metal,
especially lower silver concentrations, a concentration by flotation is mandatory.
References
1. Reuter MA, UNEP (2013) Metal recycling: opportunities, limits, infrastructure, international
resource panel
2. Patino F, Salinas E, Cruells M, Roca A (1998) Alkaline decomposition–cyanidation kinetics of
argentian natrojarosite. Hydrometallurgy 49:323–336
3. Hanke G, Melcher F, Antrekowitsch J (2016) Characterisation of by-products of the zinc industry.
In: OPMR 2016 Opportunities in processing of metal resources in South East Europe, pp 184–190