School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, South Africa; Department of Mineral Processing Division, Johannesburg, South Africa; Department of Civil and Chemical Engineering, University of South Africa, College of Science Engineering and Engineering, Johannesburg, South Africa
Mpho, M., School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, South Africa, Department of Mineral Processing Division, Johannesburg, South Africa; Samson, B., School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, South Africa, Department of Mineral Processing Division, Johannesburg, South Africa; Ayo, A., Department of Civil and Chemical Engineering, University of South Africa, College of Science Engineering and Engineering, Johannesburg, South Africa
Low grade ferromanganese tailing was subjected to different mineralogical techniques, reduction roasting and magnetic separation to establish whether commercially acceptable manganese qualities and high Mn/Fe ratio could be obtained, and also to determine the best processing route for beneficiating this ore. The main manganese mineral within the feed sample is birnessite, with minor amounts of pyrolusite and todorokite. Size by assay analysis conducted presented a result with a yield of about 35.75% and Mn grade of 27.63% to coarse (-3.35 + 1 mm) and yield of 20.24% and Mn grade of 27.71% to (-1.18 + 0.50 mm) fraction. Two-stage high induced magnetic separations at 16,000 and 11,000 G produces Mn grades with similar grade to that obtained from the ferromanganese feed sample. Reduction roasting followed by magnetic separation on -1.18 + 0.50 mm at 1000 G recovered 72.31% Mn with a grade of 58.44% Mn, 2.52% Fe and 3.29% Si at Mn/Fe ratio of 23.22. This study reveals the influence of roasting in converting the hematite and goethite to magnetite and the response of the roasted fraction to magnetic separation. © 2013 Published by Elsevier B.V.
