PROCESSING OF PYRITE CONCENTRATES WITH THE EXTRACTION OF NON- FERROUS METALS: NICKEL AND COBALT TECHNOLOGY ELABORATION

Abstract

ABSTRACT. The paper presents the results of the development of a technology for processing of pyrite concentrates with the extraction of non–ferrous metals, iron and sulphur using the technology of two–stage dissociating roasting with hydrometallurgical processing of cinder. Hydrometallurgical processing of cinder was studied. It comprised of two steps – cinder leaching and extraction for processing multi–component solutions. Based on the results of laboratory tests, balance experiments were conducted on the chemical enrichment of nickel –poor and cobalt–pyrite concentrates. The experiments included (i) Thermal decomposition of pyrite concentrate at a temperature of 660 – 700° C and a duration of 60 minutes, an oxygen flow rate of 30–50% of the stoichiometric; (ii) Leaching of the cinder with a HCl solution at a temperature of 90°C, liquid: solid = 8:1, pH 2,7 and a duration of 60 minutes; (iii) Filtration of pulp and precipitation of nickel and cobalt from solutions with iron sulphide. During leaching, mainly iron is transferred to the solution; nickel and cobalt remain in a small amount of cake (the cake weight is reduced by almost ten times compared to the thermal decomposition product). As a result, up to 99% of non–ferrous metals are extracted into the concentrate, and the solution becomes more concentrated in iron.

Keywords

• pyrite concentrates
• sulphidising roasting
• nickel and cobalt