Kinetic Model for Vanadium Extraction by CO2–O2 Mixed Injection Based on Interfacial Reactions of Emulsified Droplets
摘要
During the vanadium extraction process of converter smelting, the core of achieving “carbon-preserving vanadium extraction” lies in the precise control of the selective oxidation of carbon and vanadium. Although traditional thermodynamic analysis can define the reaction direction, it is difficult to quantify the extremely complex dynamic process of interfacial reaction behavior of emulsified droplets in the emulsion zone triggered by CO2–O2 mixed injection. Through experimental and theoretical analysis, this study systematically investigated the selective oxidation behaviors of carbon and vanadium in vanadium-bearing hot metal under CO2–O2 mixed injection at 1623 K. Thermodynamics–kinetics coupled model for carbon-preserving vanadium extraction was established based on mass transfer theory. By solving the interfacial oxygen potential model and the emulsified droplet generation model simultaneously, key parameters were determined, including the reaction interface area (A = 2.237 × 10−4 × FG × t m2), mass transfer coefficient for decarburization (KC ≈ 1.947 × 10−3 m/s), and mass transfer coefficient for vanadium extraction (KV ≈ 2.201 × 10−2 m/s). The reliability and accuracy of the proposed model are verified by experimental data. The established model can quantitatively characterize the dynamic evolution of carbon and vanadium contents under variable CO2–O2 blowing operational parameters and provide theoretical basis and technical reference for parameter optimization, process regulation, and efficient realization of carbon-preserving vanadium extraction in industrial converter smelting.