为研究不同煤熔渣对高铬砖的侵蚀机制，选取4种物理化学性能差异较大的典型气化炉用后煤熔渣，采用化学分析、XRD、SEM及EDS等研究了不同煤熔渣的性能及其对w（Cr2 O3）≥90％的高铬砖的侵蚀、渗透情况。结果表明：气化炉中煤熔渣主要由SiO2、CaO、Al2 O3、Fe2 O3、MgO组成，但不同煤熔渣的化学组成差异较大，矿物组成及熔融特性温度也不同；在相同条件下，高铬砖侵蚀的主要影响因素是温度和熔渣的化学组成，随温度升高，煤熔渣对高铬砖的侵蚀急速加剧；煤渣中的熔融指数较低时，煤熔渣对高铬砖的侵蚀渗透较为严重；煤熔渣中低熔点相向材料内部渗透、渣中SiO2等对材料中ZrO2等的反应溶解是造成高铬砖失效的直接原因；高铬砖表面形成镁铝铬铁复合尖晶石致密层可以有效降低高铬砖的侵蚀程度。
Four used coal slags from a typical gasifier with different chemical compositions and physical properties were chosen,and their properties and the corrosion and penetration to high chrome bricks (Cr2 O3≥90 mass%)were studied by chemical analysis,XRD,SEM and EDS in order to research the cor-rosion mechanism of different coal slags to high chrome bricks.The results indicate that:(1)the four molten coal slags from gasifier are mainly composed of SiO2 ,CaO,Al2 O3 ,Fe2 O3 ,and MgO,and their contents vary with the coal kind obviously,which leads to the different mineral compositions and melting characteristic temperatures of coal slag;(2)under the same conditions,the main factors influencing the corrosion to high chrome bricks are temperature and chemical compositions;with the temperature rising,the corrosion to high chrome bricks aggravates markedly;(3)corrosion and penetration of coal slag to high chrome bricks are severe when the melting index R of coal slag is low;(4)penetration of low melting phases in coal slag to bricks,and reaction and dissolution between SiO2 in coal slag and ZrO2 in high chrome bricks lead to the direct failure;(5)a dense complex spinel (Mg,Fe)(Cr,Al,Fe2O4)layer is formed near the hot face of high chrome brick,which reduces the erosion degree effectively.
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