不锈钢冶炼底吹CO_(2)对熔池动力学条件影响  

Effect of bottom blowing CO_(2)on dynamic conditions of molten pool in stainless steel smelting

作　　者：周赟 魏光升 朱荣[1,2] 董凯 ZHOU Yun;WEI Guang-sheng;ZHU Rong;DONG Kai(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing Key Laboratory of Research Center of Special Melting and Preparation of High-end Metal Materials,Beijing 100083,China)

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]高端金属材料特种熔炼与制备北京市重点实验室,北京100083

出　　处：《钢铁》2023年第1期39-46,共8页Iron and Steel

基　　金：国家自然科学基金资助项目(52004023,52074024);山东省重大科技创新工程资助项目(2019JZZY010358);江西省重点研发计划资助项目(20214BBG74005)。

摘　　要：近年来,CO_(2)在钢铁行业的资源化利用技术被广为开发,研究表明CO_(2)在不锈钢冶炼中的应用颇具潜力。通过建立底吹CO_(2)气泡反应动力学模型并结合水力学模拟试验研究,量化研究不锈钢冶炼条件下底吹CO_(2)对熔池动力学条件的影响。由于CO_(2)脱碳导致气体体积增加会造成气泡膨胀或分裂的情况不明确,假设两种极端条件,即条件a,CO_(2)反应气泡体积增大后只膨胀不分裂;条件b,CO_(2)反应气泡体积增大后只分裂不膨胀,并取某厂70 t不锈钢炉冶炼中期工艺参数对两种条件下CO_(2)气泡反应动力学进行计算。结果表明在本研究条件下,不锈钢冶炼底吹CO_(2)反应后气体增加无论是导致气泡膨胀或者分裂,反应平衡时气泡最终体积约为初始体积的1.3倍,并且气泡体积随反应时间的变化呈线性关系。水力学模拟研究发现,相对于对照组试验,条件a和条件b下熔池的混匀时间分别缩短16.5 s和8.4 s,因此得出实际底吹CO_(2)在反应后会使熔池混匀时间缩短8.4~16.5 s,使熔池的动力学条件得到显著改善。此外,通过墨水示踪剂观察底吹CO_(2)对熔池流场变化的影响,发现底吹CO_(2)反应后导致气泡膨胀会促进熔池的溶质向横向扩散,相对抑制溶质在纵向的扩散速度;相反地,CO_(2)反应后导致气泡分裂会促进熔池的溶质向纵向扩散,相对抑制溶质在横向的扩散速度。In recent years,the resource utilization technology of CO_(2)in the iron and steel industry has been widely developed.The research showed that the application of CO_(2)in stainless steel smelting has great potential.The effect of bottom blowing CO_(2)on the dynamic conditions of molten pool under the condition of stainless steel smelting was quantitatively studied by establishing the dynamic model of bottom blowing CO_(2)bubble reaction and combined with hydraulic simulation experiment.Since it is not clear that the increase of gas volume caused by CO_(2)decarburization will cause bubble expansion or splitting,two extreme conditions is assumed,namely,condition a.CO_(2)bubble only expands without splitting after the increase of gas volume;condition b.CO_(2)only splits without expanding;taking the medium-term process parameters of 70 t stainless steel furnace in a plant,the CO_(2)bubble reaction kinetics under the two conditions was calculated.The results showed that under the conditions of this study,the gas increase after the bottom blowing CO_(2)reaction during stainless steel smelting,whether it leads to bubble expansion or splitting,the final bubble volume at the reaction equilibrium was about 1.3 times of the initial volume,and the bubble volume changes linearly with the reaction time.The hydraulic simulation study found that compared with the control group experiment,the mixing time of the molten pool under condition a and condition b was shortened by 16.5 s and 8.4 s respectively.Therefore,it was concluded that the actual bottom blowing CO_(2)would shorten the mixing time of the molten pool by 8.4-16.5 s after the reaction,and significantly improve the dynamic conditions of the molten pool.In addition,the effect of bottom blowing CO_(2)on the flow field of molten pool was observed by ink tracer.It was found that the bubble expansion caused by the reaction of bottom blowing CO_(2)would promote the lateral diffusion of solute in molten pool and relatively inhibit the longitudinal diffusion speed of solute.On

关 键 词：不锈钢冶炼 底吹CO_(2) 动力学模型 气泡体积 混匀时间 流场 

分 类 号：TF764.1[冶金工程—钢铁冶金]