Conventional gravity separation process of iron mineral fines is not very effective. In present work MultiGravity Separation (MGS) process has been studied. This study was performed on a low-grade iron ore namely goethiticlateriticore (GLO) from Eastern India. Detailed mineralogical, physical and chemical characteristics of a goethiticlateriticiron ore showed that the sample contained porous and friable oxides and hydroxides of iron. The ore sample had afeed grade of 54.43% total Fe, 9.27% SiO2 and 8.02% Al2O3. Hematite and goethite are main iron-bearing minerals whilekaolinite and gibbsite are the major gangue mineral constituents. Considering the characterization data, these ores wereground separately to three size fractions, namely -300 μm, -250 μm and -150 μm sizes and subjected to flowing filmconcentration in Wilfley Table. As revealed by the liberation study, higher concentration was obtained by the processingof -150 μm crushed sample. The grade of the ore was improved from 54.43% Fe to 65.71% Fe. However, significantamount of fine iron ore particles were lost during the processing of -150 μm size ore, because it is not very effectivefor particles less than 15 μm. Thus, fine hematite and goethite particles are usually not recovered resulting in the loss ofvaluable iron ore fines. To recover this fine, Multi Gravity Separator was used in place of Wilfley Table and was found tobe effective in reducing loss of fine iron particles and increasing the grade of the concentrate. The MGS process improvedthe Fe from 54.43% to 66.5% along with decreasing the alumina from 8.02% to 1.17%.
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