Kinetics of pre-reduction of manganese ore by CO

Abstract

The degree of reduction of the higher oxides of manganese to the lowest oxide, MnO, achieved during the pre-reduction of manganese ore has a direct impact on the energy consumption for the subsequent smelting process. For ferruginous manganese ores, understanding the kinetics of pre-reduction is also useful for controlling the process parameters to optimise specific power consumption and maximise the metal recovery for upgrading by magnetic separation. The effects of reduction temperature, gas composition and particle size on the rate of reduction were investigated. Based on experimental results, the controlling step and activation energy for this reduction process were determined, and the rate expression was also developed.