Melting and separation behavior of slag and metal phases in metallized pellets obtained from the direct-reduction process of vanadium-bearing titanomagnetite

•Conditions for effective separation of slag and metal phases were found.•The melting–separation process could be divided into three stages.•There were some inclusions of residual carbon and sulfur in the metal phase.•The slag was mainly composed of geikielite, silicate, and titanium oxide.

With increasing attention to environment and energy issues, it is important to utilize vanadium-bearing titanomagnetite resource effectively in ironmaking industry. In this paper, melting and separation behavior of metallization pellets produced in a direct-reduction process of vanadium-bearing titanomagnetite was studied. The results showed that the effective separation of slag and metal phases could be obtained in which over 95% Fe was transferred into metal phase and over 90% Ti was remained in slag under the conditions of reducing atmosphere and complete carburizing; there were some inclusions of residual carbon and sulfur in the metal phase; the main components in the slag are geikielite, titanium oxide, aluminum silicate, magnesium silicate, and a small amount of iron and its oxides; the complete separation of slag and metal phases was achieved at the condition of 1500 °C, holding time of 50 min, reducing atmosphere, and limited carburization; it was considered that the melting and separation process of metallization pellet could be divided into three stages of which slag and metal respectively and sequentially melted and gathered, the molten slag leaked while metallized pellet shrank, and then the slag and metal phases separated from each other completely.