Concentration of a Sudanese low-grade iron ore

The iron ore deposit of the Northern State of Sudan, at Wadi Halfa, is a huge deposit, but is low in grade. It assays 36% Fe and 48% silica. The present study is an attempt to investigate the amenability of this newly discovered ore for upgrading. Based on the appreciable differences in specific gravity and magnetic susceptibility between the desired iron minerals and the gangue minerals, it was suggested that gravity separation and/or magnetic separation may be useful to concentrate this type of low-grade ore. As a result of the fine dissemination of the iron minerals and the most abundant gangue mineral, quartz, the optimum degree of grind is around 150 μm. Using two-stage separation, roughing and cleaning, it was possible to obtain a high grade concentrate assaying about 64% Fe at a recovery of 72%.