Behaviors of Denitrogenation in RH-MFB  

作　　者：ZHOU Jian QIN Zhe ZHANG Bo PENG Qi-chun QIU Sheng-tao GAN Yong 

机构地区：[1]National Engineering Research Center of Continuous Casting Technology, Central Iron and Steel Research Institute [2]Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology

出　　处：《Journal of Iron and Steel Research International》2013年第7期40-44,共5页

摘　　要：According to the analysis related to kinetic mechanism of vacuum denitrogenation and combining with the actual production of RH-MFB （a combination of Ruhstahl-Hausen vacuum degassing process with a multifunctional oxygen lance） at Liansteel, the limit step and model equation of vacuum denitrogenation are determined. Meanwhile, the influencing factors of nitrogen removal from liquid steel in vacuum of RH-MFB are analyzed. The results show that the limit step of vacuum denitrogenation in RH-MFB is the mass transfer of nitrogen in liquid boundary layer and the reaction follows first order kinetics. Keeping the necessary circulation time under the working pressure （67 Pa） is helpful to nitrogen removal from steel. The oxygen content in molten steel has little influence on the removal of ni-trogen after deep deoxidation, while the sulphur content in liquid steel is always relatively low and has little effect on denitrogenation. The sharp decrease of carbon content in steel drives the process of denitrogenation reaction so as to exhibit a faster denitrogenation rate. The interracial chemical reaction and argon blowing play a major role in the ni-trogen removal when the carbon content in liquid steel is stable.According to the analysis related to kinetic mechanism of vacuum denitrogenation and combining with the actual production of RH-MFB （a combination of Ruhstahl-Hausen vacuum degassing process with a multifunctional oxygen lance） at Liansteel, the limit step and model equation of vacuum denitrogenation are determined. Meanwhile, the influencing factors of nitrogen removal from liquid steel in vacuum of RH-MFB are analyzed. The results show that the limit step of vacuum denitrogenation in RH-MFB is the mass transfer of nitrogen in liquid boundary layer and the reaction follows first order kinetics. Keeping the necessary circulation time under the working pressure （67 Pa） is helpful to nitrogen removal from steel. The oxygen content in molten steel has little influence on the removal of ni-trogen after deep deoxidation, while the sulphur content in liquid steel is always relatively low and has little effect on denitrogenation. The sharp decrease of carbon content in steel drives the process of denitrogenation reaction so as to exhibit a faster denitrogenation rate. The interracial chemical reaction and argon blowing play a major role in the ni-trogen removal when the carbon content in liquid steel is stable.

关 键 词：RH-MFB denitrogenation KINETICS influencing factor 

分 类 号：TF769.4[冶金工程—钢铁冶金]