A Study of Processing High-Grade Magnetite Concentrates by Combination of Magnetic Separation and Reverse Flotation Separation to Prepare Raw Materials for Ferrite Magnet

摘要

Permanent magnets (PM) are critical components for electric motors and power generators. Non-rare earth (non-RE) PMs typically have small supply risks and low cost compared to rare earth element (REE) PMs. There is a try to purify super high-grade magnetic concentrate to prepare raw materials for ferrite magnet of non-RE PMs. Beneficiation of a high-grade (68%) iron ore concentrate was investigated by combination of the low-intensity magnetic separation and reverse flotation methods. The granulometric composition was determined by laser particle size analyzer. Element analysis was assessed by semiquantitative XRF analysis, and mineralogical composition was evaluated by powder X-ray diffraction. The effects of the magnetic field intensity during magnetic separation were investigated on the performance of the wet low-intensity magnetic separation (WLIMS). The optimum flotation conditions of starch as depressant were determined. With the combination of magnetic separation and reverse flotation separation, product of >72% Fe and <0.2% silicate grade was produced for preparing ferrite magnet.