An efficient process for the beneficiation of a low grade chromite ore

AbstractThe applicability of centrifugal force multigravity separator (MGS) to concentrate fine fractions (–0·1 mm) of a low grade chromite ore assaying 9·3%Cr2O3 was investigated. The metal screen analysis revealed that 83·92% of the material prepared for tests was in the +0·106 mm fraction containing 8%Cr2O3 and that 16·08% was in the –0·106 mm size fraction containing 16·12%Cr2O3. The +0·1 and –0·1 mm fractions of the ore was used as feed for shaking table and MGS tests respectively. The results gathered from shaking table test were not satisfactory due to low Cr2O3 recoveries. However, a chromite concentrate with 46·22%Cr2O3 grade and 66·1 wt-%Cr2O3 recovery was obtained by the combination of shaking table and MGS. It was clearly demonstrated that MGS is an ideal beneficiation equipment for fine fractions of a low grade Cr2O3 ore. Based on the experimental results, a principal flowsheet for the enrichment plant was proposed.