|矿物组成对高炉渣破碎粒化效果的影响机理  

Mechanism of mineral composition on effect of blast furnace slag granulation

作　　者：康月 张玉柱 刘超 邢宏伟 孙瑞靖 裴晶晶 KANG Yue;ZHANG Yuzhu;LIU Chao;XING Hongwei;SUN Ruijing;PEI Jingjing(College of Metallurgy and Energy,North China University Science and Technology,Tangshan 063210,Hebei,China)

机构地区：[1]华北理工大学冶金与能源学院,河北唐山063210

出　　处：《钢铁》2023年第10期172-182,共11页Iron and Steel

基　　金：河北省重点研发计划资助项目(22373805D);河北省自然科学基金资助项目(E2021209079)

摘　　要：高炉渣作为炼铁过程产生的主要副产品,析晶能力大小决定了其作为活性材料的潜力,非晶相含量越高,高炉渣活性越强,其中气淬喷吹工艺可有效增加高炉渣冷却速率,制备高含量非晶相渣珠,提高高炉渣利用附加值。通过热力学模拟及原位观察法阐释高炉渣矿相演变过程,解析连续冷却过程中高炉渣矿相析出机理,确定高炉渣初始析晶温度、初晶相及临界冷却速率,同时对不同碱度的高炉渣析晶活化能和阿弗拉米指数进行了计算,获取高炉渣粒化过程利于抑制矿相析出的炉渣成分组成。结果表明,碱度为0.9~1.3时,高炉渣连续冷却过程析出初晶相均为钙铝黄长石,初始析晶温度随碱度的增加逐渐升高,黄长石析出量随碱度的增加而增多,但是碱度增加到1.2后开始有一部分黄长石相转变为硅酸二钙相;同时碱度的增加抑制钙长石和斜辉石的析出,但是对尖晶石析出量影响不大。随着碱度的增加,高炉渣析晶临界冷却速率逐渐加大,阿弗拉米指数逐渐增大,析晶活化能数值逐渐减小,因此高碱度高炉渣需要较大过冷度来抑制矿相析出,利于获得高含量非晶相渣珠。同时对不同碱度高炉渣进行气淬喷吹得到高炉渣珠,非晶相含量随碱度减小而增加,渣珠透明度逐渐增加,非晶含量高于国家标准GB/T 18046-2008矿渣中非晶相质量分数不得小于85%的要求,为高炉熔渣高附加值资源化及余热高效利用提供理论基础。As the main by-product in the ironmaking process,the blast furnace slag(BFS)crystallization capacity determines its potential as an active material.The higher the amorphous phase content,the stronger the activity of the BFS.The gas quenching process can effectively prepare high content amorphous slag beads as increasing the BFS cooling rate,which improves the BFS added value utilization.The BFS mineral phase evolution process is explained and the mineral phase precipitation mechanism is analyzed in the continuous cooling process through the thermodynamic simulation and in-situ observation method,which determines the initial crystallization temperature,initial crystal phase and critical cooling rate.At the same time,the crystallization activation energy and Avrami index are calculated to obtain the BFS composition which is conducive to inhibiting the mineral phase precipitation in the granulation process.The results show that,the initial crystal phase of the BFS with the basicity range of 0.9-1.3 are all gehlenite in the continuous cooling process.The initial crystallization temperature gradually increases and the precipitation amount of melilite increases with the increase of basicity,but a part of the melilite begins to change into dicalcium silicate when the basicity increases to 1.2.At the same time,the increase of basicity inhibits the precipitation of anorthite and augite,but has little effect on the precipitation of spinel.The BFS crystallization critical cooling rate gradually increases,the Avrami index gradually increases,and the crystallization activation energy gradually decreases with the increase of basicity.Therefore,high basicity BFS requires large overcooling to inhibit the mineral phase precipitation,which is conducive to obtaining high content amorphous slag beads.At the same time,the slag beads is prepared by gas quenching BFS with different basicities.The amorphous phase content increases and the transparency degree of slag beads gradually increases with the decrease of BFS basicity,and the amo

关 键 词：高炉渣 析晶 原位法 恒温冷却 析晶活化能 

分 类 号：TF534[冶金工程—钢铁冶金]