Beneficiation Process Test of a Refractory Iron Ore in Zimbabwe

In order to determine the reasonable beneficiation process and technical indicators of the refractory iron ore in Zimbabwe and better develop its iron ore resources , a lot of process condition tests were carried out based on ore properties such as chemical element analysis of the raw ore, iron phase, mineral composition, and dissociation degree analysis of main mineral monomers. Finally, the process flow of stage grinding-low-intensity magnetic separation-pulsed high-gradient magnetic separation- cationic reverse flotation was determined. The results show that the useful iron minerals in the ore are mainly magnetite and hematite, and the crystal size is fine, mainly distributed below -0.05 mm. At the condition of primary grinding particle size P₈₀ 63 μm, the first stage low-intensity magnetic separation and high-intensity magnetic separation are carried out, and the second stage low- intensity magnetic separation, high-intensity magnetic separation and cationic reverse flotation are carried out at the condition of secondary grinding particle size P₈₀ 45 μm. The qualified iron concentrate with yield of 38.25%, iron grade of 66.75% and SiO₂ content of 3.56% can be obtained, which meets the target requirement of concentrate grade ≥ 66.20%.