Abstract This article records the degradation of the refractory alumina-silicate lining in a boiler furnace combusting dendromass after ten years of use. The deterioration of refractory alumina material was evaluated from phase and chemical analyses of accretions. The fusion temperatures of accretion were measured with a high-temperature microscope and the results were compared with the solidus (point of first liquid formation) temperature predicted by FactSage 7.3 thermodynamic simulation software. Content of SiO2 (50–65%) in accretions confirms that fine silicate particles of ash adhere to the lining. These silicates react with subliming alkalis from the dendromass and form aggressive eutectic melts on surface of lining at operating temperatures. Increase in operating temperature, inhomogeneity (porosity) and alkali content in accretions are the main factors influencing accretion viscosity, melt convection and lining corrosion. For this reason accretions on the vertical walls lower down are much thicker than on the walls in the upper part and the arch. The Al2O3 concentration is higher in the arch accretions; there the refractory material corrodes intensively. The fusion temperatures of the glassy accretions (measured at the furnace atmosphere: accretion boundary) are around 1150 °C. However, the calculated temperatures of slag formation stated by FactSage are about 150 °C lower, and these correspond to the operating temperature in the upper section of the combusting chamber. The fusion temperatures increase with the Al2O3 content in accretions closer to the lining. The obtained results will be applied to define the requirements for the development of boiler furnace refractories.

中文翻译：

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锅炉燃烧室沉积物对树枝状物质的分析

摘要 本文记录了锅炉炉膛燃烧树状物中耐火硅酸铝内衬在使用十年后的降解情况。耐火氧化铝材料的劣化通过堆积物的相和化学分析来评估。用高温显微镜测量吸积物的熔化温度，并将结果与​​ FactSage 7.3 热力学模拟软件预测的固相线（第一次液体形成点）温度进行比较。堆积物中 SiO2 的含量（50-65%）证实了细小的灰分硅酸盐颗粒粘附在衬里上。这些硅酸盐与来自树枝状物质的升华碱反应，并在操作温度下在衬里表面形成侵蚀性的共晶熔体。工作温度升高，沉积物中的不均匀性（孔隙度）和碱含量是影响沉积物粘度、熔体对流和衬里腐蚀的主要因素。由于这个原因，下方垂直墙壁上的堆积物比上部和拱形墙壁上的堆积物厚得多。拱形增生中的 Al2O3 浓度较高；耐火材料在那里强烈腐蚀。玻璃状吸积物的熔化温度（在熔炉气氛下测量：吸积物边界）约为 1150 °C。然而，FactSage 规定的炉渣形成的计算温度低约 150 °C，这些温度对应于燃烧室上部的工作温度。熔化温度随着靠近衬里的增生中的 Al2O3 含量而增加。