Magnetic separation as part of new nickel concentrate processing technology at Kola MMC: performance analysis and upgrade. Part II

Abstract

The change in Kola Mining and Metallurgical Company JSC (KMMK) smelter technology upon processing nickel concentrate from separation of copper-nickel matte considerably toughened the requirements to nickel powder of tube-type furnaces be ing subject to chlorine dilution in tank house. The operational imperfection of current technology of magnetic separation site when separating the non-magnetic component, and the peculiarities of the raw materials behavior discovered at the start of production have required the site upgrade. The research presented in the materials is the second part of the work on considering ways to improve the quality of the resulting product by separating materials based on the difference in their magnetic properties. In the present paper, we consider feasibility of control magnetic separation. The performance of control magnetic separation were determined upon the change in feed size, rotation frequency of the drum and magnetic field strength at the main and control separation. The research undertaken has determined the operation parameters of the expected process flowsheet of magnetic separation site consisting of two process units: two-stage crushing-classification and two-stage magnetic separation. According to the experimental data reported, the recommended crushing operation parameters are set, both the magnetic induction field and rotation frequency defined at the main and control separation. Calculation of performance indicators for nickel powder recovery as per the suggested flowsheet has been has been carried out, losses of nickel returned to head units of nickel raw materials process chain (work-in-process) have been estimated for two process flowsheets, current and perspective.