Abstract
In this study, a magnetic hydro-sizer was used to upgrade the final Fe concentration grade of a magnetite ore. The impact of the magnetic field intensity and water flow rate on the concentration grade were investigated. The chemical composition, mineralogical phases and surface topography of the feed to the hydro-sizer were analysed using XRF, XRD and SEM respectively. The results revealed that the feed to the magnetic hydro-sizer contained 61.25% Fe. Major phases in the feed are magnetite, hongquiite, calcium magnesium catena-silicate and quartz. SEM results showed that the sample was well liberated. A concentrate containing 63.9% Fe was produced whilst operating at particle size distribution of 80% passing 180 μm, water flow rate of 290m3/hr and a magnetic intensity of 1350gauss. The higher the magnetic intensity, the lower the Fe grade of the concentrate. The higher the water flow rate, the higher the Fe grade of the concentrate. For a magnetic hydro-sizer, operating field should be between 1200 and 1350 gauss and a water flow rate above 260m3/hr for the final concentration of magnetite.