Beneficiation of low grade Manganese ore (Elluvial) from Kodur Mines, Andhra

Beneficiation of low grade manganese ore (elluvial) from Kodur mines, Andhra, was studied by jigging, tabling, magnetic separation and flotation. The sample assayed 33.94 percent Mn, 4.53 percent Fe, 14.01 percent SiO2, 3.50 percent Al2O3, 8.65 percent Ba and 0.49 percent P. The unusually high barium content occurred in the manganese mineral psilomelane and limited the grade of concentrate that could be produced by ore-dressing methods. Of the various methods studied, magnetic separation yielded the best recovery of 36.4 percent in the magnetic product assaying 43.2 percent Mn. Jigging of the coarse fraction of the ore and tabling of the fine size recovered concentrate assaying 44.79 percent Mn. Tabling gave lower recoveries than either jigging or magnetic separation, the best recovery being 65.3 percent manganese, concentrate assaying 44.8 percent Mn. The phosphorus content was high in all the concentrates ranging from 0.37 to 0.28 percent. For making ferro-manganese the product could therefore be used only after blending with low phosphorus ores, if at all.