... furnaces, hot blast furnaces, heat treatment furnace, cracking furnaces, roaster, melting furnace, soaking pit furnaces, oil gas boiler, etc in the ... , alumina, corundum and corundum mullite. 1. Physical & chemical properties: Performance index Mullite Cordierite Corundum Chemical Content SiO2 25-30% 46-52% 8-11 ...