120 t顶底复吹转炉双渣留渣法冶炼低磷钢  

SMELTING LOW PHOSPHORUSSTEEL BY DOUBLE SLAG RETENTION METHODIN 120 t TOP-BOTTOM DOUBLE-BLOWN CONVERTER

作　　者：唐武 罗锐 韩建成 Tang Wu;Luo Rui;Han Jiancheng(Xiangtan Iron and Steel Group Co.,Ltd.,Xiangtan 411101,Hunan)

机构地区：[1]湘潭钢铁集团有限公司,湖南湘潭411101

出　　处：《河北冶金》2024年第12期58-62,共5页Hebei Metallurgy

摘　　要：钢中磷含量会限制降低钢材的塑性和韧性,还会使钢材的焊接性能变差,严重影响成品的质量。随着国民经济的发展,行业对超低磷钢板需求量大幅上升,但是其生产难度极大,国内仅宝钢、武钢、南钢等为数不多的几家钢铁企业开发成功。为解决湘钢当前装备下低磷钢生产去磷的问题,通过对120 t转炉顶底复吹双渣留渣工艺进行不断地优化改进,在合理的废钢比、造渣控制、供氧控制、底吹控制等条件下,湘钢形成了极低磷钢的冶炼工艺。双渣留渣工艺可保证炉渣前期较高的碱度和氧化亚铁含量,促进前期快速成渣,未留渣炉次前期碱度平均为1.21,而留渣炉次的前期碱度平均为1.92;控制温度在1 350℃左右,脱磷率可以稳定在80%左右。通过双渣留渣的工艺优化,2023年低磷钢种磷含量合格率保持在较高的水平,磷含量合格率逐渐从2022年的80%提高到90%甚至100%。在终点成分稳定的基础上,湘钢实现了稳定的转炉极低磷钢磷含量的控制。The phosphorus content in steel will limit and reduce the plasticity and toughness of steel,and will also make the weldability of steel deteriorate,seriously affecting the quality of the finished product.With the development of the national economy,the industry's demand for ultra-low phosphorus steel plate has risen sharply,but its production is extremely difficult,and only a few iron and steel enterprises such as Baosteel,Wugang and Nangang have developed successfully.In order to solve the problem of phosphorus removal in the production of low phosphorus steel under the current equipment of Xiangtan company,the smelting process of extremely low phosphorus steel has been formed under the conditions of reasonable scrap ratio,slag formation control,oxygen supply control and bottom blowing control through the continuous optimization and improvement of the 120 t converter top-bottom double-slag retention process.The double slag retention process can ensure the higher basicity and ferrous oxide content of slag in the early stage,and promote the rapid slag formation in the early stage.The average basicity in the early stage of non-slag retention furnace is 1.21,while that in the early stage of slag retention furnace is 1.92.The control temperature is about 1350℃,and the dephosphorization rate can be controlled at about 80%.Through the process optimization of double-slag slag retention,the qualified rate of phosphorus content of low-phosphorus steel in 2023 is maintained at a high level,and the qualified rate of phosphorus content is gradually increased from 80%in 2022 to 90%or even 100%.On the basis of stable composition at the end point,the phosphorus content of the very low phosphorus steel in the converter is controlled by Xiangtan.

关 键 词：顶底复吹转炉 低磷钢 双渣留渣法 脱磷率 碱度 

分 类 号：TF55[冶金工程—钢铁冶金]