Effect of blast furnace dust as a reductant on direct reduction roasting for separating titanium and iron in seaside titanomagnetite

The feasibility and mechanisms of using the blast furnace dust as a reductant in direct reduction-low intensity magnetic separation of Indonesian seaside titanomagnetite were investigated. The results show that the blast furnace dust can be used as an alternative to coal as a reductant under the condition of fluorite as an additive. Under the synergistic effect of the blast furnace dust and fluorite,the recovery and grade of iron in the reduction iron powder can be increased and the content of TiO₂ can be decreased at the same time during the direct reduction process. Simultaneously,iron in the blast furnace dust can also be recovered. A comparison of three different kinds of blast furnace dusts indicates that the composition of the blast furnace dust can influence the effect of reduction.Under the same dust dosage,the Jinxin blast furnace dust(referred to as JX) show the best reduction performances. The optimum conditions of roasting reduction are the blast furnace dust dosage of 30%,the fluorite dosage of 10% and reduction at 1250℃ for 60 min. The reduction iron powder,with 91.28% Fe grade,0.93% TiO₂ content and 89.19% total iron recovery including iron in the run-of-mine and blast furnace dust,is obtained after the roasted product is processed by using a process of two-staged grinding and two-staged magnetic separation.