水煤浆气化炉用氧化铬砖的显微结构研究

摘要

为了更深入地研究水煤浆气化炉用再结合法氧化铬砖的蚀损机制,利用X-Ray荧光仪、场发射扫描电镜和能谱仪研究了使用前后砖样的化学组成和显微结构.原砖是用电熔氧化铬颗粒、氧化铝粉和氧化锆粉经高温烧结制成的,在氧化铬颗粒和氧化铝之间通过固相反应形成(Al2-x,Crx)O3固溶体;用后残砖的显微结构表征为工作表面形成显量的Al2O3-SiO2-CaO-FeO系玻璃相,反应层的主要反应产物是尖晶石固溶体和一些硅酸盐.砖的蚀损机制主要是液体熔渣冲蚀了工作面上的晶间和粒间结合.%For more in-depth research on erosion mechanism of re-bonded chrome oxide bricks for coal slurry gasifiers,the chemical composition and microstructure of the bricks before and after use were analyzed by means of X-ray fluorescence spectrometry and FESEM-EDS.The original brick was made from fused Cr2O3 particles,Al2O3 fines and zirconia fines by firing at high temperatures.And (Al2-x,Crx) O3 solid solution was formed in the brick through the solid reaction between Cr2O3 and Al2O3.The microstructure characterization of the used brick showed that a massive glassy phase of Al2O3-SiO:CaO-FeO system was formed in the working surface.The main reaction products in the reaction zone were spinel solid solution and some silicates.The main erosion mechanism is that the bonding of intercrystals and intergrains in the working surface was disintegrated and eroded by the molten slag.