Characterization and engineering application of a novel ceramic composite insulation material

Abstract Thermal insulation materials have attracted increasing attention in recent years for energy conservation in thermal power plant. A novel ceramic composite insulation material (hereafter refer to CCIM) composed of alumina fibers and hollow silica powders with excellent pliability and thermal insulation properties has been designed and fabricated. The effects of alumina fiber and hollow silica microspheres on the performance of composite were characterized through microstructure observation using scanning electron microscopy (SEM) and thermal conductivity evaluation. In the novel CCIM, ceramic fibers and particles of different sizes were uniformly mixed to form multi-scale sizes of pores which can decrease the heat conduction and convective heat transfer at high temperature significantly. The comparison between the traditional mineral wool and the fabricated CCIMs focused on microstructure and thermal insulation property was also performed in this work. The novel CCIM shows much lower thermal conductivity than the standard value of thermal conductivity of traditional inorganic insulation materials when the mean temperature is between 126 °C and 538 °C. The novel CCIMs were applied in a supercritical Power Plant. The surface temperature and surface heat flux measured during service in the supercritical Power Plant further demonstrated that the novel ceramic composite has better insulation properties than traditional inorganic insulation materials.