Possibility of “Topionica” - Veles Pb-Zn slag valorization by gravity concentration procedure

Abstract

This paper presents the results of laboratory tests of the valorization possibility of Pb-Zn slag "Smelter" -Veles, by gravity concentration. It is an inhomogeneous raw material that has a significant content of non-ferrous metals, primarily Pb, Zn and Cu, as well as the presence of precious metal in the form of Ag. The contents of the mentioned non-ferrous metals vary from a few percent to over 10%. The content of silver also varies from a few grams per ton to as many as tens of grams per ton of technogenic raw materials. Mineralogical analysis of the products of the grinding experiment by size classes determined that the useful components from Pb-Zn slag "Veles" are free at grinding fineness of -0.1 + 0.00 mm. Thus, the prepared technogenic raw material was subjected to magnetic separation and gravitational concentration processes. In this paper, only gravitational concentration is treated. It was decided to perform the gravitational concentration of the individual size classes on the Wilfley 13 shaking table, with the selected table surface for small classes and sludges. The obtained results of gravitational concentration of different size classes show that there was a separation of individual components into separate products.. This operation of the lead separation into concentrate (ΔH fraction) and silver in lead concentrate (ΔH fraction) was relatively successful, while the separation of zinc and copper in concentrate (ΔH fraction) gave slightly worse results. The best results in terms of content of Pb, Zn, Cu and Ag in concentrate (ΔH fraction) were achieved for the largest class (-100 + 75 μm) where the content of Pb in this product is 8.44%, zinc 7.42%, copper 0.77% and silver 125 g/t. In all other concentrates (ΔH fractions) obtained from smaller size classes, lower contents of non-ferrous metals and silver in them were obtained.