Performance calculation of slag from vanadium titano-magnetite by full oxygen bath smelting process

Abstract

Vanadium titano-magnetite is an important iron ore resource containing iron, vanadium and titanium. Although iron and vanadium can be recovered by the traditional blast furnace process, titanium can only be stored in the form of TiO2 bearing slag, which resulting in a great waste of titanium resources. In the full oxygen bath smelting process, thanks to high oxygen potential, low nitrogen content and no coke bed in the furnace, the reduction of TiO2 in the slag. This may lead to slag viscosity, inhibit the smelting of vanado-titano-magnetite, and obtain a slag with high TiO2 content. Based on slag coexistence theory, a multi system coexistence theoretical model of vanadium titano-magnetite smelting slag is established, and the influence of slag basicity on the concentration of slag components and the ratio of sulfur between slag and iron is calculated. The results show that with the increase of slag basicity, the interaction concentration of TiO2 in slag decreases gradually, which makes the reduction of TiO2 more difficult and is conducive to the smelting of vanadium–titanomagnetite. Under the optimum alkalinity and reduction temperature (R=1.1, melting temperature is 1500 °C), the distribution ratio of S element between slag and iron is 6.57, and the theoretical S concentration in molten iron is 0.073%. The molten iron can meet the steel-making requirements after pretreatment and desulfurization.

Keywords

• Vanadium titano-magnetite
• Bath smelting
• Slag
• Interaction concentration
• Sulfur distribution ratio