Effect Of CO₂ Blowing Modes On Vanadium Oxidation In Hot Metal

A large amount of CO₂ emissions has caused humankind to face a severe problem of global warming.China's crude steel output reached 996 million tons in 2019.The output of steel produced by converter accounts for about 85%,and the production per ton of steel produces about 2.2 tons of CO₂;the output of steel produced by electric arc furnace accounts for about 15%,and the production per ton of steel produces about 0.8tons of CO₂.China's steel industry produced a total of 1.982 billion tons of CO₂ in2019.Almost all processes in steel production produce CO₂,such as sintering,ironmaking,and steelmaking.How to efficiently utilize the CO₂ emitted in the steel production process is the focus of metallurgical workers at home and abroad,and some related research has been carried out.Based on the previous research of our research group,this study carried out the experimental research of steelmaking with CO₂-O₂ mixed bottom-blowing,and top-bottom combined blowing.The effect of CO₂ on the vanadium extraction process under different blowing modes was discussed.The optimal ratio,appropriate initial blowing temperature,and blowing flow of CO₂ were obtained under different blowing modes.The research results are of theoretical and guiding significance for the industrial application of CO₂ in extracting vanadium from V-containing hot metal in the converter.In this work,the following conclusions were obtained.The research results show that:(1)The results of the CO₂-O₂ mixed bottom-blowing experiment shows that when the ratio of CO₂ varied from 10%to 25%,the ratio of 15%resulted in the best vanadium extraction effect,and the oxidation rate of vanadium reached the maximum,95.65%.At the time,the oxidation rate of carbon reached the minimum,30.87%.(2)The results of the top-blowing O₂ combining bottom-blowing CO₂ show that with the increasing proportion of CO₂ from 10%to 25%,the oxidation rate of vanadium first increased and then decreased,and reached the maximum,94.70%,as the proportion of CO₂ was 20%.At the same time,the oxidation rate of carbon reached the minimum,27.83%.(3)For the above two blowing modes,the initial blowing temperature of 1300 ^oC and the blowing flow rate of 0.6 L/min(about 1.714 L/(min·kg))are beneficial to vanadium extraction and carbon retention in hot metal.