화학공학소재연구정보센터
Minerals Engineering, Vol.137, 217-231, 2019
The role of manganese ore reduction morphology development in setting reduction mechanisms
Manganese ores differ extensively in their mineralogical and bulk chemical composition. Consequently these ores follow different mineralogical morphology development paths as the reduction reaction proceeds in the production furnace. Mineralogical factors such as composition and distribution of initial liquid silicate formed at specific temperatures, as well as iron and manganese metallisation patterns, are significant determining factors in the relative importance of different parallel reduction reaction mechanisms in each ore type. Applied mineralogy techniques were used to identify and analyse matrix liquid silicate phase formation in manganese ore reacted at 1300 degrees C with Carbon Black reductant. The study includes three South African ores from the Kalahari Manganese Field, the ores represent both the Wessels-type and Mamatwan-type mineralogy. FactSage computational thermodynamic calculations were made to explain liquid silicate phase formation and its evolution with increased reaction time. Matrix silicate phase liquidus temperatures and pseudo-ternary phase diagrams in the MnO-FeO-SiO2-CaO-MgO-Al2O3 composition system were calculated. Matrix liquid silicate formed at the relatively low reaction temperature of 1300 degrees C within all three ores, although different quantities of liquid silicate formed along differing composition paths set by ore mineralogy.