Moses C. Siame and Kazutoshi Haga and Atsushi Shibayama
Treatment of LowGrade Iron Ore Using Two Stage Wet HighIntensity Magnetic Separation Technique
781 - 786
2017
11
11
International Journal of Materials and Metallurgical Engineering
https://publications.waset.org/pdf/10008252
https://publications.waset.org/vol/131
World Academy of Science, Engineering and Technology
This study investigates the removal of silica, alumina and phosphorus as impurities from Sanje iron ore using wet highintensity magnetic separation (WHIMS). Sanje iron ore contains lowgrade hematite ore found in Nampundwe area of Zambia from which iron is to be used as the feed in the steelmaking process. The chemical composition analysis using Xray Florence spectrometer showed that Sanje lowgrade ore contains 48.90 mass of hematite (Fe2O3) with 34.18 mass as an iron grade. The ore also contains silica (SiO2) and alumina (Al2O3) of 31.10 mass and 7.65 mass respectively. The mineralogical analysis using Xray diffraction spectrometer showed hematite and silica as the major mineral components of the ore while magnetite and alumina exist as minor mineral components. Mineral particle distribution analysis was done using scanning electron microscope with an Xray energy dispersion spectrometry (SEMEDS) and images showed that the average mineral size distribution of aluminasilicate gangue particles is in order of 100 μm and exists as ironbearing interlocked particles. Magnetic separation was done using series L model 4 Magnetic Separator. The effect of various magnetic separation parameters such as magnetic flux density, particle size, and pulp density of the feed was studied during magnetic separation experiments. The ore with average particle size of 25 µm and pulp density of 2.5 was concentrated using pulp flow of 7 Lmin. The results showed that 10 T was optimal magnetic flux density which enhanced the recovery of 93.08 of iron with 53.22 mass grade. The gangue mineral particles containing 12 mass silica and 3.94 mass alumna remained in the concentrate, therefore the concentrate was further treated in the second stage WHIMS using the same parameters from the first stage. The second stage process recovered 83.41 of iron with 67.07 mass grade. Silica was reduced to 2.14 mass and alumina to 1.30 mass. Accordingly, phosphorus was also reduced to 0.02 mass. Therefore, the two stage magnetic separation process was established using these results.
Open Science Index 131, 2017