Experimental Research On Al-Fe Separation And Mechanism Of Oolitic Hematite

The high alumina oolitic hematite belong to refractory iron, it is difficult to achieve Al-Feeffective separation by conventional beneficiation process. On the basis of physicochemicalproperties and mineralogy characters are studied, through depth reduction-dry magneticseparation process deal with high alumina oolitic hematite of Guizhou Hezhang, achieve Al-Feeffective separation, detection methods such as XRD and SEM investigate the Al-Fe separationmechanism.Single fractor test results show that: when additives YS-1amount of5.66%, reducing agentamount of15.0%, reduction temperature at1350℃, reduction time at40min, the roasted orecrusher to-2mm, after dry magnetic separation of a coarse and a lean which magnetic fieldintensity are119.4kA/m, reduced iron product grade of93.16%, recovery of88.45%, whichAl₂O₃content of2.02%, high alumina slag Al₂O₃grade of18.60%and iron content of12.25%.Al-Fe separation mechanism is following: Roasted ore is mainly composed of Fe andCaO·Al₂O₃·2SiO₂, also a small amount of MgO·Al₂O₃, Fe₂SiO₄, CaSi₄O₈. The high reductiontemperature is benefit for the generation of Fe, CaO·Al₂O₃·2SiO₂and CaSi₄O₈,and the ironprecipitation and growing up. When reducing agent excessive, FeO·Al₂O₃and CaO·Al₂O₃·2SiO₂appear in reduced iron products is the root cause of its grade and aluminum content. The mainphase of aluminum in the high alumina slag is CaO·Al₂O₃·2SiO₂, in addition to2CaO·Al₂O₃·SiO₂,3CaO·Al₂O₃·3SiO₂,3CaO·Al₂O₃·2SiO₂.