Characterization of Egyptian Manganese Ores for Production of High Carbon Ferromanganese

Abstract

This work aims at studying the reactivity of Egyptian manganese ores to be used in the production of ferromanganese alloys in submerged electric arc furnace. Ores with different manganese content (high-medium and low) were selected and characterized by X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM). The main mineralogical compositions in the three ores are pyrolusite (MnO2) and hematite (Fe2O3). Porosity of selected Mn ores was determined. The reactivity of the different ores was carried out through pre-reduction of the selected ores using thermobalance at 900°C and 1100°C and mixture of CO and CO2 gases. The reduction process was done until steady weight. The reduced ores were examined using XRD and SEM. The results showed that pyrolusite in high and medium ores are converted completely to MnO at 1100°C. However, the ore with low manganese content was converted to MnO and Mn3O4. Consequently, it is clear from the results that Mn ores with high and medium MnO2 content are more reactive than those with low MnO2. Therefore, high MnO2 content Mn ores are preferable to get good economic impact during the production of high carbon ferromanganese.