REDUCTION OF IRON CONTENT BY MAGNETIC SEPARATION FOR OLIVINE USE AS A REFRACTORY RAW MATERIAL

In this study, the potential of reducing the iron content in an olivine sample obtained as the final tailing in chromite enrichment was examined via magnetic separation methods. Within this scope, the as-received sample was firstly divided into three fractions as +212, -212+150 and -150 µm. Dry magnetic separation was then applied to the coarse fractions and wet magnetic separation for the fine fraction. The results were evaluated using parameters such as the weight percentage of non-magnetic fraction, Fe2O3 content and iron removal (%). In addition, changes in the quantities of mineralogical phases in non-magnetic fractions were determined by XRD analysis. For +212 and -212+150 µm, it was determined that optimum values can be reached in the current intensity ranges of 0.50-0.75 and 1.0-2.0 A, respectively. Although not comparable, it was observed that the effective separation for -150 µm was achieved in the range of 2.0-3.0 A. Iron content decreasing with decreasing particle size confirms these results. The decreases in the peak intensities of the phases with high iron content in the XRD patterns were also found to be compatible with the magnetic separation results. Overall results showed that the iron content in the olivine rich sample can be reduced to the limit values required for the refractory raw material by magnetic separation. © 2021 Union of Chambers of Engineers and Architects of Turkey. All rights reserved.