Competitive growth of crystals in vanadium–chromium slag

Abstract

Based on the classic kinetic theory of crystallization, we have developed a mathematical model to describe the crystallization behavior of crystals in complex vanadium–chromium slag systems. The results show that the crystallization rates of spinels, olivines and augites are dominated by the component with the highest melting point. The sequence of the crystallization ability of crystals in vanadium–chromium slag is as follows: FeCr₂O₄ > Mg₂SiO₄ > FeV₂O₄ > MgSiO₃ > Fe₂TiO₄ > Mn₂SiO₄ > MnSiO₃ > Fe₂SiO₄. The optimum temperature ranges for the crystallization of these crystals are 1497–1547 K, 1380–1430 K, 1301–1351 K, 1192–1242 K, 1098–1148 K, 1069–1119 K, 1038–1088 K and 985–1035 K, respectively. We also find that with the increase in Cr₂O₃/V₂O₃ and decrease in SiO₂/FeO, the total crystallization rate of spinels increases remarkably, while the TiO₂ content has little effect on the crystallization of spinels in vanadium–chromium slag.