摘要
以某厂70 t钢包为研究对象,采用数值模拟的方法对比了吹氩量对钢包内不同比表面积和预热温度的废钢熔化行为.结果表明:废钢熔化速度随着比表面积的增加而加快;底吹氩气可显著加速废钢熔化,但随着比表面积的增加吹气的促进效果逐步减弱.有底吹氩时,比表面积为120、130.22和160.81 m2·m-3的废钢中心温度上升速率相较于无底吹氩时分别提高了7.06、6.51和3.73 K·s-1,熔化速率分别增加了0.92、0.88和0.28 cm3·s-1,熔化时间分别缩短了17、15和3 s.板形废钢初始温度由300升到1000 K时,其熔化速度由2.97提高到3.26 cm3·s-1,熔化时间缩短了3 s.底吹氩流量显著影响废钢熔化速度,当氩气流量由100增至200 L·min-1时,比表面积为120、130.22和160.81 m2·m-3的废钢熔化时间分别由44减小到35 s、42减小到34 s及34减小到31 s.
Abstract
More steel scrap consumption in the iron and steel industry can not only mitigate the shortage of iron ore resources but also greatly lower production costs and carbon emissions to the atmosphere, which is a crucial link in low-carbon metallurgy. Because of the drawbacks of different factors, the amount of steel scrap consumed in the current converter steelmaking process is restricted, and the technology of multipoint adding scrap comes into play. Thus, steel scrap addition into ladles has gradually garnered attention from metallurgical experts, but there are few reports on the three-dimensional melting behavior of steel scrap in a real ladle environment with argon blowing. To examine the melting law of steel scrap in a ladle, in this study, the flow field, temperature distribution, and melting behavior of steel scrap in a 70 t refining ladle at various argon blowing rates with steel scrap addition of different specific surface areas and preheating temperatures were numerically investigated and compared using a mutiphysical mathematical model. The results revealed that the melting rate of steel scrap increases with increasing specific surface area, and bottom argon blowing can accelerate the melting of steel scrap, while the promoting effect gradually decreases with increasing specific area. With bottom argon blowing, the core temperature of steel scrap with specific surface areas of 120, 130.22, and 160.81 m2·m-3 increased by 7.06, 6.51, and 3.73 K·s-1, the melting rate was increased by 0.92, 0.88, and 0.28 cm3·s-1, and the melting time was shortened by 17, 15, and 3 s, respectively, compared with those without bottom blowing. When the initial temperature of steel scrap increases from 300 to 1000 K, the melting rate increases from 2.97 to 3.26 cm2·s-1 and the melting time is shortened by 3 s accordingly. The argon blowing rate significantly influenced the melting rate of steel scrap. When the argon blowing rate increases from 100 to 200 L·min-1, the melting time of steel scrap with specific surface areas of 120, 130.22, and 160.81 m2·m-3 is reduced from 44 to 35 s, 42 to 34 s, and 34 s to 31 s, respectively. Thus, on the premise of smooth production, the melting speed of the steel scrap in the ladle can be significantly increased by increasing the argon blowing rate and adding the slab scrap at higher initial temperatures and specific surface areas. This work offers a reference for developing steel scrap rapid-melting technology for ladles in steel plants.
维普
万方数据