According to the dual needs of heat transfer and thermal insulation in incinerators, different parts of the incinerators are designed with refractories of different SiC contents. Water vapor is mainly concentrated in the zones of feeding, drying and combustion, and the main damage factors of SiC refractories include high temperature and hydration. The results of hydration resistance of typical SiC-containing refractories show that the higher the SiC content, the worse the hydration resistance. Si3N4-SiC refractories after oxidation treatment have good hydration corrosion resistance, which are appropriate for water-cooled wall of waste incinerators.