Nowadays the major part of primary produced zinc arises from the hydrometallurgical route. Depending on the used method huge amounts of residues from neutral leaching, iron precipitation as well as lead-silver-residues are generated. Specifically the iron precipitates are dumped worldwide in a large scale and often show an environmental problem. Therefore the present work characterizes and evaluates these materials to get a better understanding for the behaviour of these residues under different test conditions. The base for this evaluation is a detailed literature survey, describing the generation process and the mineralogical composition of the mentioned residues. At the department of nonferrous metallurgy an extensive characterization of a lead-silver-residue, two different sodium-jarosites and a goethite residue were carried out. The aim is to achieve a better understanding of the behaviour of the mentioned materials under different conditions (atmosphere, temperature, etc.) by combining morphological information from scanning electron microscopy with melting-, reduction- and sintering points determined by hot stage microscopy and thermogravimetric analysis. These findings were supported by thermochemical calculations and lab scale trials, which concentrate mainly on the behaviour under increased temperature and the influence of different atmosphere and additives.
|Translated title of the contribution
|Characterization and evaluation of residues from primary hydrometallurgical zinc winning processes
|16 Dec 2011
|Published - 2011
Bibliographical noteembargoed until 09-11-2016