Vanadium Extraction Theory And Jet Characteristics Of Multiple Gas Injection In Converter

There exists selective oxidation of carbon and vanadium in the process of vanadium extraction in converter.The process has been already very mature at present.However,the effect of vanadium extraction in converter is influenced by only 50%oxygen supply intensity of that of conventional converter steelmaking,the limitation of carbon-oxygen reaction as well as the weak reaction kinetic condition.Based on this,the mixture of N₂ and CO₂ in the oxygen jet is proposed,and the endothermic effect and kinetic energy of jet flow of N₂ and CO₂ can be used to control the temperature of molten pool,strengthen the molten pool agitation,and improve the thermodynamics and kinetics of vanadium extraction.In this paper,the conversion temperature of vanadium oxidized by CO₂ was obtained by analyzing the selective oxidation of carbon and vanadium in the vanadium extraction process.By comparing the physical and chemical heat of different gases,it was found that CO₂ had the best cooling effect in both chemical and physical heat.The model of material and heat balance by injecting multiple gases in vanadium extraction converter were established.It was found that when CO₂ injection ratio was 46.6%,the residual heat of the system was zero.After mastering the thermodynamics law of multiple gases participating in vanadium extraction in the converter,the stirring energy density was studied based on the bubble behavior analysis in molten pool,which was found that the stirring energy density was affected by some factors.Their influencing degree were decreased gradually from CO₂ utilization rate,the position of oxygen lance,top blowing flow rate,smelting temperature to top blowing?O₂+CO₂?gas ratio.Based on above theoretical analysis,the jet characteristics of multiple gases were studied by Fluent numerical simulation software.The results showed that when the inlet pressures of the gases were same,the order of jet velocity from high to low was nitrogen,oxygen and carbon dioxide.When multiple gases entered the oxygen lance nozzle,the speed was rapidly increased,resulting in forming a stable high-speed zone at the outlet of the nozzle.And from then on,the jet flow was continuously attenuated and the speed was gradually decreased.The research in this paper confirmed that the thermodynamics and kinetic conditions of extracting vanadium could be improved by using multiple gases?O₂+N₂+CO₂?,which provided a theoretical support for optimizing the process of vanadium extraction in converter.