无取向电工钢RH脱硫工艺技术研究

【作者】 邱钰杰；

【导师】 虞澜；

【作者基本信息】 昆明理工大学 ， 钢铁冶金， 2011， 硕士

【摘要】 目前,攀枝花钢铁(集团)公司无取向电工钢的生产仅依靠铁水深脱硫、降低转炉回硫来控制硫含量,硫含量仅能控制在0.008%以下,已无法满足用户对无取向电工钢质量的要求。因此为满足客户对无取向电工钢质量日益增长的要求,攀钢急需开发高牌号的超低碳、超低硫无取向电工钢。本研究以攀钢现有生产条件为依据,确定了真空室直接加入脱硫剂的加入方法；并针对CaO-CaF2渣系的脱硫剂,对设备造成严重侵蚀以及对环境造成较大影响的问题,通过实验室钢渣试验,利用二次正交回归试验方法,筛选出了以CaO-Al2O3为基础渣系,优化了MgO、BaO、CaF2、Na2O等化学组分含量的RH用低氟脱硫剂配方：CaO/Al2O3值：2～2.2,MgO:6%～9%, BaO:13%～15%, CaF2:5%-8%, Na2O:适量。提高了脱硫效率、无取向电工钢成品硫含量降低了37.5%以上,并且减轻了RH脱硫过程中对设备的侵蚀以及环境的污染。通过在攀钢进行的工业试验,确定了脱硫处理时间、钢包顶渣组成以及钢包顶渣碱度等无取向电工钢RH脱硫的关键工艺控制条件：(1)RH进站钢包顶渣碱度要求在5以上；(2)钢包顶渣中的(FeO+MnO)含量要控制在12%以下；(3)RH处理过程中脱硫时间在10min以上；(4)钢包顶渣中Mg0含量控制在8-10%。在此基础上,开发出了适合攀钢现阶段生产实际的无取向电工钢RH脱硫工艺。工艺路线为：LF工序调整钢包顶渣碱度在5以上,(FeO+MnO)含量在10%以内；RH吹氧强制脱碳后自然脱碳15min。真空脱碳结束后,加入脱硫剂,真空循环10min。钢水处理完后对RH设备进行喷补。采用新工艺,攀钢无取向电工钢的硫含量成功降到0.005%以下,提高了攀钢无取向电工钢的质量,为开发更高级别无取向电工钢奠定了基础。更多还原

【Abstract】 Currently, in Panzhihua Iron & Stell (Group) Co. the sulfur content in non-oriented electrical steel is controlled by deep desulfurization of iron and reducing the sulfur content of sulfur from converter, but the sulfur content just arrive at 0.008% or less,which is unable to meet the quality of non-oriented electrical steel. Therefore, there is an urgent need to research and develop high quality non-oriented electrical steel with ultra-low carbon, ultra low sulfur in Panzhihua Iron & Stell (Group) Co..In this paper, based on Panzhihua Iron & Stell (Group) Co.’s production equipments system and process, the auther have explored a desulfurization method of directly adding the desulfurization agent into the vacuum chamber of RH furnace. The use of CaO-CaF2 slag desulfurization equipment will cause severe erosion and the environment pollution, the auther haved experimented and selected a kind of low fluoride RH slags which is mixture of CaO,Al2O3,MgO, BaO, CaF2 and Na2O. By comprehensive consideration of physicochemical properties of slag in the study, the optimized composition of refining slag ought to be CaO/Al2O3 value:2～2.2, MgO:6%～9%, BaO:13%～15%, CaF2:5%～8%, Na2O: moderate. The use of new formulations sulfur content have decreased 37.5% in finished non-oriented electrical steel product,reduces the erosion of equipment and environmental pollution.We have determined the key process control conditions of RH desulfurization by the industrial study in Panzhihua Iron & Stell (Group) Co. for example the desulfurization processing time, ladle slag composition and ladle slag alkalinity.(1)The alkalinity of ladle slag is required not less than 5.(2)The (FeO+MnO) content in ladle slag should be controlled to below 12%.(3)RH desulfurization process should more than 10 minutes.(4)The MgO content in ladle slag should be controlled between 8% and 10%.On this basis, we identified a suitable non-oriented electrical steel RH desulfurization process at this stage Panzhihua Iron & Stell (Group) Co..Process route is:LF process should control the ladle slag alkalinity not less than 5 and the (FeO+MnO) content below 10%.It more than 10min of natural decatbutization after force decarbutization. The vacuum cycle time more than 10min after sorbent was added.when the end of desulfurization equipement should be maintenance.The sulfur content in non-oriented electrical steel is controlled to below 0.005% or more less by the new process, which increases non-oriented electrical steel quality and lays a foundation for the development of higher level of non-oriented electrical steel.更多还原