Siliceous Manganese Ore from Eastern India: A Potential Resource for Ferrosilicon-Manganese Production

Abstract

Siliceous manganese ore, associated with the banded iron formation occurs in large volume in northern Odisha, India. It is a sub-grade ore containing 21% Mn, 60% SiO 2 and 3% Fe, hence do not find any use and considered as waste. Such ore does not respond to any physical beneficiation techniques because of intricate microstructure and poor liberation of Mn-phase. It could only be up-graded to 32%Mn with 36% yield and 52% recovery by processing it through mineral separator followed by WHIMS. Siliceous manganese ore along with calcite and coke in appropriate ratio, when charged to a plasma reactor, a product with slag metal ratio of 2.5:1 was obtained within a period of 10 min. Electron probe micro-analysis of the metal confirmed it to be ferrosilicomanganese while the slag constitute of tricalcium silicate (C3S) with around 5% Mn in adsorbed state.