Relationship Between Liquid Fluidity of Iron Ore and Generated Liquid Content During Sintering

The fluidity of sintering liquid phase reflects the effective bonding range of the binder phase in the sintering process of iron ores. In this study, the liquid composition and quantity during sintering was calculated using FactSage 7.0 thermodynamic calculation software. The results show that two liquid phases are formed during sintering. One phase is generated at about 1373 K (1100 °C) and the other is generated at about 1523 K (1250 °C). The liquid fluidity index and the low-temperature liquid phase are closely related. The higher-temperature liquid phase has little influence on the liquid fluidity index. The larger the amount of low-temperature liquid phase generated, the higher the liquid fluidity index is. The alkalinity of the low-temperature liquid phase has insignificant influence on the liquid fluidity index. The content of SiO₂ in the iron ore is the main factor that affects the liquid fluidity index during sintering. The liquid fluidity index increases greatly with increasing SiO₂ content. In contrast, Al₂O₃ content has little influence on the liquid fluidity index, with an increase in the Al₂O₃ content only slightly increasing the liquid fluidity index. An increase in the MgO content of the iron ore can reduce liquid generation, promote the spinel generation, and decrease the liquid fluidity index during sintering.