Effect of Iron Ore Properties on Melting and Assimilation Phenomena in Parallel Granulation with Inclined Mixing of Limestone

Abstract

The declining quality of iron ore fines and increasing re-use requirement of steelmaking slag have led to higher Al₂O₃ content in sinter products. High grade concentrated hematite ore (concentrate) has been emerged as a potential solution for reducing Al₂O₃ levels of sinter. However, research regarding on the melting and assimilation behavior of concentrates in sintering process is limited. On the other hand, our previous work demonstrated that Parallel Granulation with Inclined Mixing of Limestone, based on the creation and mixing of pseudo-particles with high and low CaO/Fe₂O₃ ratios, can improve the sinter strength and productivity. To investigate the melting and assimilation characteristics of concentrates, we conducted melt dripping tests various kind of iron ore, revealing that adhesive layers with high concentrate content have low melt retention capacity. Furthermore, sinter pot tests under single granulation condition showed that when a large amount of concentrate is blended, fragile sinter cake is formed due to insufficient melting and assimilation. Sinter pot tests using Inclined Mixing of Limestone demonstrated that melting and assimilation are promoted by positioning concentrate near abundant melt sources.