Beneficiation of low grade Manganese ore from Miragpur Mines, Balaghat, Madhya Pradesh

A low grade sample from Miragpur mines, Balaghat, Madhya Pradesh, assayed 34.45% Mn, 2.08% Fe 17.72 % SiO2, 8.5% Al2O3, 2.3% Ca Braunite, Psilomelane, and a little Cryptomelane. Garnet was abundant. The other gangue minerals were hematite, quartz, manganese silicates, feldspar and clay. They were finely intergrown with the ore minerals. Both flotation and electro-static separation could eliminate a large amount of grant and quartz. Flotation yielded a conc. Of grade 40.7% Mn, 7.50% Fe, 6.71% Al2O3,7.62% SiO2 and 0.098% P with a recovery of 30.8% Mn. Heating to 800° C -900°C increased the manganese content of this concentrate to 44.63%. Straight Electro-static separation produced a concentrate assaying 39.85% P with a recovery of 40.3% Mn. On heating to 800°-900°C, grade followed by magnetic separation and electrostatic separation yielded a conc. Of grade 46.23% Mn, 6.6% Fe,(Mn/Fe ratio 7.0)11.19% SiO2, 8.23% Mn, 6.6% Fe ratio in this concentrate was high , the silica and alumina contents were too high to be used for standard ferro-manganese production. Being a highly complex-ore, the grade of concentrate and recovery obtainable were rather low. For better results, hydrometallurgical methods may have to be adopted for this ore.