Beneficiation of low-grade manganese ore from Mansar mines, Madhya Pradesh

Abstract

A low-grade manganese ore sample from Mansar Mines, Madhya Pradesh, assaying 32.67 percent Mn, 27.48 percent SiO2, 10.13 percent Fe and 0.46 percent P,was received for beneficiation tests. The ore consisted essentially of braunite, with fair amounts of psilomelane and a little pyrolusite. The gangue minerals were quartz, mice, clay, barite, rhodonite and calcite. Due to the intimate association of the manganese minerals with the gangue, fine grinding was necessary for their liberation. Magnetic separation followed by tabling of the classified magnetic products recovered 65.2 percent manganese in a concentrate of grade 48.76 percent Mn, 11.44 percent SiO2,11.2 percent Fe and 0.16 percent P. Magnetic separation followed by floatation of the magnetic products yielded a concentrate assaying 47.94 percent Fe, and 0.03 percent P, with a manganese assays by about 1.8 percent. Straight tabling can yield a concentrate of grade about 48 percent Mn but the phosphorus content in it is high (0.24%).A combination of magnetic separation and tabling or flotation was found necessary to bring down the phosphorus within the specification for metallurgical grade.