喷粉精炼超低硫钢工艺的试验研究

LABORATORY RESEARCH ON REFINING ULTRA-LOW SULFUR STEEL BY POWDER INJECTION

本文研究了喷粉精炼超低硫钢的工艺。在试验室中用30kg感应炉进行的喷粉试验表明:要得到高的脱硫率,首先要控制好顶渣成分和氧化性。而要进一步脱硫到超低硫水平,还必须向钢液中加入脱硫剂。文中对喷吹CaO、CaSi粉和CaO基复合粉剂在低硫时的脱硫特点及顶渣对脱硫的影响进行了对比试验和讨论。试验中稳定地获得了[S]<0.001%的超低硫钢液,

Technique was studied of refining ultra-low sulfur steel by powder injection with a laboratory 30 kg induction furnace. Experimental results show that proper basicity and low oxygen potential of the top slag are two important factors for achieving a high level of desulfurization. Still, powder injection is a must to obtain ultra-low sulfur steel. Ability of three kinds of powder: CaO, CaSi and Cao-based composite were tested. Utilization of CaSi powder was lower than the composte powder due to the shallow pool of steel in the furnace. The desulfurizing capacity of CaO-based composite powder was increased significantly due to CaF_3 and Al powder additive. It is noticed that CaO was more efficient in desulfurization than CaSi powder when sulfur concentration was very low in the steel, that suggests that ability of removing impurity inclusions and other mechanisms are also important factors besides chemical reactions in deslufurization by powder injection. The effects of the composition and the oxygen potential of the top slag on desulfurization were studied as well. In this work, it was proved a regular practice to obtain ultra-low sulfur steel with [S]<0.001%.