AOD炉渣对镁钙质耐火材料的侵蚀机理  

Corrosion Mechanism of AOD Slag on Magnesia Calcium Refractories

作　　者：王恭一 赵惠忠[1] 黄日清 张寒[1] 余俊[1] 李学臣 WANG Gongyi;ZHAO Huizhong;HUANG Riqing;ZHANG Han;YU Jun;LI Xuechen(The State Key Laboratory of Refractory and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China;Guangxi Beigang New Materials Co.,Ltd.,Beihai 536000,China;Zibo Development and Reform Commission,Zibo 255000,China)

机构地区：[1]武汉科技大学省部共建耐火材料与冶金国家重点实验室,武汉430081 [2]广西北港新材料有限公司,北海536000 [3]淄博市发展改革委,淄博255000

出　　处：《硅酸盐通报》2023年第4期1496-1505,共10页Bulletin of the Chinese Ceramic Society

基　　金：校企合作基金(2021H20006)。

摘　　要：采用静态坩埚法将AOD炉渣线区镁钙砖在1700℃空气气氛下高温热处理3 h后进行抗渣试验。结合XRD、SEM、EDS等测试手段,分析了AOD炉两个阶段炉渣对渣线区镁钙砖的侵蚀机理。结果表明:低碱度的氧化期炉渣对镁钙砖侵蚀明显,炉渣在表面张力和毛细管力作用下,进入镁钙砖内部与CaO反应生成低熔点的铁酸二钙2CaO·Fe_(2)O_(3)(C_(2)F),促进砖中CaO溶解,破坏了原有的致密结构,使反应层结构变得疏松、易剥落;镁钙砖中方镁石晶簇吸收液态渣中的铁、铬、锰氧化物,并在其晶内和晶间形成复合尖晶石结构,从而提高镁钙砖表面渣的黏度,减缓渣的侵蚀;还原期炉渣碱度较高,对镁钙砖的侵蚀作用较弱,主要表现为SiO2向砖内侵蚀渗透,以及体积效应和温度梯度导致镁钙砖表面小尺寸方镁石晶簇向渣中剥落。The slag resistance test of MgO-CaO bricks in slag line area of AOD furnace was carried out by means of static crucible method after high temperature heat treatment at 1700℃for 3 h in air atmosphere.The corrosion mechanism of two kinds of AOD furnace slags on MgO-CaO bricks in slag area of AOD furnace was analyzed by means of XRD,SEM and EDS.The results show that the oxidation period slag with low alkalinity has obvious corrosion on MgO-CaO bricks.Under the action of surface tension and capillary force,the slag enters MgO-CaO bricks and reacts with CaO to form dicalcium ferrite(2CaO·Fe_(2)O_(3),C_(2)F)with low melting point,which promotes the dissolution of CaO and destroys the origin compact structure.The structure of reaction layer becomes loose,cracked and easy to peel off.The periclase crystal cluster in MgO-CaO bricks absorbs iron oxide,chromium oxide and manganese oxide in liquid slag and forms a composite spinel structure within and between its crystals in order to improve the viscosity of liquid slag on the surface of MgO-CaO bricks and slow down the corrosion of slag on MgO-CaO bricks.The alkalinity of reduction period slag is high and the corrosion effect on MgO-CaO bricks is weak,which is mainly manifested in the corrosion and penetration of SiO2 into the bricks,and the volume effect and temperature gradient cause the peeling of small periclase crystal cluster on the surface of MgO-CaO bricks into slag.

关 键 词：AOD炉 镁钙砖 侵蚀机理 氧化期炉渣 还原期炉渣 方镁石晶簇 铁酸二钙 复合尖晶石 

分 类 号：TQ175[化学工程—硅酸盐工业]