煤熔渣对SiC-MgAl2O4复合材料的侵蚀机制  

Corrosion mechanism of molten coal slag on SiC-MgAl2O4 composite refractories

作　　者：王岚 李红霞[1] 孙红刚[1] 杜一昊 付晓晖 Wang Lan;Li Hongxia;Sun Honggang;Du Yihao;Fu Xiaohui

机构地区：[1]中钢集团洛阳耐火材料研究院有限公司先进耐火材料国家重点实验室

出　　处：《耐火材料》2019年第5期359-362,共4页Refractories

基　　金：NSFC-河南联合基金重点支持项目(U1604252)

摘　　要：为探索水煤浆气化炉炉衬材料的无铬化,以SiC颗料、MgAl2O4细粉、α-Al 2O 3微粉和MgO细粉为原料,在埋碳气氛下于1650℃保温5 h烧成制备了SiC-MgAl2O4坩埚试样,并采用静态坩埚法在埋碳气氛下进行了1500℃保温1 h的煤熔渣侵蚀试验,以研究高温煤熔渣对试样的侵蚀行为。结果表明:1)SiC-MgAl2O4材料经高温煤熔渣侵蚀后,煤熔渣沿着MgAl2O4基质渗入材料内部,产生明显裂纹;2)煤熔渣中的Fe元素在试验条件下与材料中的SiC发生氧化还原反应,在试样表面形成金属Fe,SiC被氧化形成的SiO 2向渣中溶解,提高了熔渣黏度,从而抑制熔渣的进一步渗透;3)煤熔渣对SiC-MgAl2O4材料的侵蚀机制主要包括向MgAl2O4基质的渗透和对SiC颗粒的氧化两个方面。In order to explore the chrome-free materials for the coal-water slurry gasifier lining,crucible specimens were prepared using silicon carbide aggregates,MgAl2O4 fine powder,α-Al 2O 3 micropowder and MgO fine powder as starting materials,and firing at 1 650℃for 5 h under carbon embedded atmosphere.The corrosion behavior of high temperature coal slag to the specimens was studied by the static crucible method.The results show:(1)after the SiC-MgAl2O4 material is corroded by the molten coal slag,the coal slag penetrates into the materials along the MgAl2O4 matrix,causing obvious cracks;(2)the Fe element in the slag has a redox reaction with SiC in the material under the experimental condition,forming metal Fe on the surface of the specimen,and the SiO2 formed by oxidation of SiC dissolves into the slag,increasing the viscosity of the slag,thereby suppressing further penetration of the slag;(3)the corrosion mechanism of coal slag to SiC-MgAl2O4 material mainly includes two aspects:penetration into MgAl2O4 matrix and oxidation of SiC particles.

关 键 词：SiC-MgAl2O4 煤熔渣 侵蚀机制 水煤浆气化炉 无铬化 

分 类 号：TQ175[化学工程—硅酸盐工业]