Research On Sintering Mechanism And Process Of High-iron-content Manganese Ores

High-iron-content manganese ore is one of the main types of manganese ore resources in China, with high iron, low Mn/Fe ratio and iron manganese mineral closely associated. Sintering process is a very important link of the comprehensive utilization of high-iron-content manganese ores. However, most studies of manganese ore sintering are focused on low iron manganese ores, rare research reports the sintering mineralization characteristics of high-iron-content manganese ore. This article use the high-iron-content manganese ores as research object, ascertain its sintering mineralization characteristics and appropriate process parameters, based on the study of chemical and phase compositions of high-iron-content manganese ores.The high-iron manganese roasted in air or weak reducing atmosphere(CO<5%) is easy form jacobsite, a little amount of liquid generating under1300℃. The consolidation of the roasted product is main depend on the recrystallization of jacobsite. The strength of roasted product increased with the rising of roasted temperature, and decreased with increasing of the material basicity.Under stronger reducing atmosphere (CO>20%), the reducing of hematite suppresses the product of jacobsite. The reduction product Fe3O4, FeO and MnO react with SiO2generating fayalite and tephroite. The melting point of this system is low, and a lot of liquid would be generated between1200℃to1300℃. The main roasted products are iron manganese oxide and ferromanganese olivine. The melting point decreases with the increasing of basicity. The main phases of the high basicity product are iron manganese oxide and calcium manganese olivine.The study of sintering process showing, the appropriate parameters are as follows:moisture of mixture9.1%, coke powder9.9%and sintering negative pressure7kPa. And the corresponding yield, ISO tumbling index and utilization coefficient reached at80.18%,61.27%and1.315t·m-2·h-1, respectively. The content of CO in sintering exhaust was 7.5%～8.0%, and the main phases of sinter were the same with the product of high-iron-content manganese ores roasted under stronger reducing atmosphere. These further confirmed the sintering atmosphere is strong reducing atmosphere.