Beneficiation of a low-grade Bed ore of manganese from Kodur Mines, Andhra

Beneficiation of a low-grade bed ore of manganese from Kodur Mines, Andhra, assaying 33.49 % Mn, 13.92 % Fe, 8.45% SiO2, 0.29% P, 7.45% Al2O3, and 2.34% Ba, was studies by jigging, tabling, straight magnetic separation after reduction. The predominant manganese mineral in the ore was psilomelane with smaller quantities of braunite; pyrolusite and vredenbergite. Clay, quartz, altered feldspar, limonite, limestone, garnet and sillimanite were the gangue minerals. Jigging followed by tabling gave a combined concentrate assaying 44.03% Mn and 10.96% Fe with a manganese recovery of 72.1%. Sintering increased the grade to 48.92%. The alternative procedure of magnetic separation after a reducing roast gave a concentrate assaying 52.87% Mn and 5.68% Fe, with manganese recovery of 66.6%.Phosphorus was high in all the concentrates and the concentrates could be utilised for the production with low-phosphorous ores.