高温条件下石灰活性度的变化行为研究  

Study on evolution behavior of the quick-lime reactivity under high temperature

作　　者：牟其强 李建立[1,2] 张梦旭 朱仁林 MOU Qiqiang;LI Jianli;ZHANG Mengxu;ZHU Renlin(Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking,Wuhan University of Science and Technology,Wuhan 430081,China;Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,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：《炼钢》2020年第5期79-84,共6页Steelmaking

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

摘　　要：钢渣中f-CaO引起的体积稳定性是目前钢渣综合利用的主要障碍之一。f-CaO来源于未完全溶解的活性石灰和硅酸三钙的分解。针对石灰未完全溶解产生的f-CaO,需要强化石灰在转炉吹炼过程中的溶解行为。石灰的活性决定着石灰溶解的效率,而石灰的活性度与其微观组织结构紧密相关。通过实验室内制取石灰样品,采用SEM、XRD和压汞仪对样品进行微观结构检测分析,依据YB/T 105—2005标准测定样品的活性度,研究了高温条件下活性石灰的活性度和微观结构的演变规律。试验结果表明,随着温度的升高,活性石灰的活性度和孔隙率均降低,孔隙的平均直径增大;CaO晶体在晶界迁移的作用下逐渐长大。微观结构的变化与石灰活性度的变化趋势紧密相关,因活性石灰内部CaO晶体变形长大和孔隙率降低,致使石灰的活性度降低。这对石灰的溶解造成障碍,不利于炉渣中f-CaO的控制。The disintegration caused by f-CaO is one of the main obstacles to the utilization of steel slag.The f-CaO come from the incomplete dissolution of the quick lime and the decomposition of tricalcium silicate.In terms of the f-CaO derived from the undissolved lime,it is necessary to strengthen the dissolution behavior of lime in the converter process.The lime reactivity plays a key role on its dissolution,and is closely related to its microstructure.The evolution behaviors of the reactivity and microstructure of quick lime under high temperature were investigated in this work.The lime samples were prepared in the laboratory,the microstructure was detected and analyzed by SEM,XRD and a mercury-injection instrument,and the reactivity was test according to YB/T 105—2005 standard.The results showed that,when temperature increased,the reactivity and porosity of the quick lime decreased,and the average diameter of pores increased.The CaO crystals grew gradually under the action of the grain boundary migration.The change of microstructure was closely related to the change trend of lime activity.On basic of the growth of CaO crystal and the decrease of the porosity,the lime activity decreased,which would obstacle the dissolution of quick lime during the steelmaking process and increase the content of f-CaO in the slag.

关 键 词：活性石灰 活性度 CAO 孔隙率 F-CAO 

分 类 号：TF703.6[冶金工程—钢铁冶金]