In order to solve the problem of solid waste pollution of basic oxygen furnace (BOF) slag in the metallurgical process, this paper took BOF slag as the research object, and carried out oxidation reconstruction of BOF slag and alcohol wet magnetic separation recovery of iron phase, so as to efficiently recover and utilize BOF slag. In the early stages, the research group realized the transformation from weak magnetic iron oxide to strong magnetic magnesia-iron spinel phase in BOF slag through oxidation reconstruction experiments under different technological parameters. On this basis, different conditions in the magnetic separation process were adjusted to achieve the optimal iron recovery rate and grade in this paper. The experimental results show that, under the appropriate reconstruction temperature, with the increase of reaction time, gas flow rate and magnetic field intensity, the iron recovery will increase and the iron grade will decrease. The most suitable magnetic field intensity is 75 mT, the magnetic material yield is 46.00%, the iron grade is 29.10%, and the iron recovery is 64.12%. Compared with the initial steel slag, the iron grade increased by 8.22%, and the iron recovery increased by 46.38% compared with the direct magnetic separation without oxidation.

The BOF slag contains a lot of iron‐containing species and its efficient recovery is a difficult problem in metallurgy. Herein, the oxidation behavior of industrial BOF slag under air atmosphere is investigated to explore the optimal oxidation conditions for transforming nonmagnetic FeO into magnetic MgFe2O4, including oxidation temperature, oxidation time, and airflow rate. The raw slag and oxidized slags are analyzed using chemical analysis, X‐ray diffraction (XRD) analysis, scanning electron microscope (SEM)‐energy dispersive spectroscopy (EDS) analysis, and Factsage thermodynamic simulation. The results show that the formation of MgFe2O4 phase is closely related to the oxidation temperature, oxidation time, and airflow rate. With the increase in temperature, the conversion rate of MgFe2O4 increases, and reaches the maximum at 1050 °C. However, the conversion rate of MgFe2O4 decreases and part of β‐C2S is converted to α‐C2S above 1050 °C. When the oxidation time and airflow rate increase, the conversion rate of MgFe2O4 increases and reaches the maximum value at 100 min and 1.25 L min−1, respectively. Correspondingly, the grade increased from 16.3% of the raw slag to 27.86% of the magnetic slag, an increase of 11.5%. This is a more convenient and effective method, which can not only bring economic benefits for relevant enterprises but also reduce environmental pollution.

The loss of permeability affects the reduction of the ferrous burden in the cohesive zone of a blast furnace (BF). Vanadia–titania magnetite (VTM) burden of various chemical compositions have different metallurgical properties. The reduction and softening-melting-dripping properties of different kinds of VTM were investigated. The results showed that the core of sinter or pellet is indirectly reduced to wustite and (Fe,Ti)Ox, and the periphery contains interlinked metallic iron and CaSiO3 in the cohesive zone. Wustite and (Fe,Ti)Ox are directly reduced in the melting-dripping zone. The aggregate (Fe, V, Cr) present in the non-dripping causes a loss of valuable components. With the increase in TiO2 content, the substrate phase of molten slag changes from melilite to titanaugite, and the mass of dripping decreases gradually. In addition, the permeability index S increased and the melting zone widened, which indicates that the increase in TiO2 content negatively affected the melting-dripping performance. The mass of the dripping is directly proportional to the pellet ratio. Considering the adverse effect of TiO2 on softening-melting-dripping properties, it is recommended that high TiO2 VTM is smelted while mixed with ordinary ores or with an increased pellet ratio in the burden structure.