冷却速率对KR脱硫渣中硫析出行为的影响  

Effect of cooling rate on precipitation behavior of sulfur in KR desulfurization slag

作　　者：蒋佳君 李建立[1,2] 朱仁林 余岳[2] 朱航宇[2] JIANG Jia-jun;LI Jian-li;ZHU Ren-lin;YU Yue;ZHU Hang-yu(Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China)

机构地区：[1]武汉科技大学钢铁冶金新工艺湖北省重点实验室,湖北武汉430081 [2]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,湖北武汉430081

出　　处：《中国冶金》2022年第3期112-118,共7页China Metallurgy

基　　金：国家自然科学基金资助项目(51974210,52074197);湖北省自然科学基金资助项目(2019CFB697)。

摘　　要：KR脱硫渣中主要成分(CaO)为转炉冶炼的优质造渣原料,通过氧化性气氛将渣中硫脱除后可将其用于转炉冶炼。但由于炉渣冷却制度不同,渣中硫的析出行为和赋存状态会发生变化,对炉渣氧化脱硫效果产生影响。基于此,以合成渣的形式探究冷速对KR脱硫渣中硫析出行为的影响,旨在明确KR脱硫渣中硫赋存状态及析出行为与冷却速率的关系,为后续通过氧化性气氛有效脱除KR脱硫渣中的硫提供理论参照,实现KR脱硫渣在转炉冶炼工艺的综合利用。采用热力学数据库FactSage8.1对炉渣的凝固过程进行模拟,采用SEM-EDS和XRD对玻璃管内冷却(快速冷却)、坩埚内冷却(中等冷却速率)以及随炉冷却(较慢冷却)渣样进行分析、检测,采用Image-ProPlus6.0对炉渣中CaS颗粒平均面积进行统计。试验结果表明,在合成渣中含有弥散分布的硫和CaS颗粒形式存在的硫。玻璃管内快速冷却渣样的硫主要弥散分布在炉渣基质相中,少量以CaS相的形式析出。坩埚内和炉内冷却渣样中硫主要以CaS颗粒形式赋存,少量硫弥散分布在基质中。随着冷却速率降低,炉渣中弥散分布的硫含量逐渐减少而CaS相析出量逐渐增加,且析出的CaS颗粒平均面积逐渐增大。KR desulfurization slag is mainly composed of high-quality slag-making raw materials(CaO)for converter smelting,which can be used in converter smelting after sulfur is removed from slag in oxidizing atmosphere.However,due to the effect of different slag cooling systems,the precipitation behavior and occurrence state of sulfur in slag will be changed,which affects the desulfurization rate.Therefore,the effect of cooling rate on the precipitation behavior of sulfur was investigated in the form of synthetic slag to clarify the relationship between the occurrence state and precipitation behavior of sulfur in KR desulfurization slag and cooling rate,and provide theoretical reference for effective removal of sulfur from KR desulfurization slag by oxidizing atmosphere,and realize the comprehensive utilization of KR desulfurization slag in converter smelting process.The equilibrium solidification process of slag was simulated by thermodynamic database FactSage8.1,and the slag samples which were taken to glass tube(rapid),crucible(moderate)and furnace(slow)cooling were analyzed and detected by SEM-EDS and XRD.The average grain size of CaS in the slag was counted by Image-ProPlus6.0.The experimental results showed that the synthetic slag contained dispersively distributed sulfur and sulfur in the form of CaS particles.The sulfur in the rapid cooling slag sample was mainly dispersed in the matrix phase of slag,and a small amount existed in the form of CaS phase.The sulfur of samples cooled in the crucible and furnace mainly existed in the form of CaS particles,and a small amount of sulfur was dispersed in the matrix.The sulfur content in the matrix phase gradually decreased,the precipitation of CaS phase in slag gradually increased,and the average area of CaS particles gradually increased with the decrease of cooling rate.

关 键 词：KR脱硫渣 赋存状态 析出行为 凝固 冷却速率 

分 类 号：TF713.3[冶金工程—钢铁冶金]