According to its production process, there are currently two types of mullite insulation bricks: sintered mullite bricks and fused mullite bricks:
1. Sintered mullite bricks are made of high-alumina bauxite clinker as the main raw material, adding a small amount of clay or raw bauxite as a binder, then molding and firing.
2. Fused mullite bricks are made of high bauxite, industrial alumina and refractory clay as raw materials, and charcoal or coke fine particles are added as reducing agents. After molding, they are manufactured by reduction fusion method.
For the mullite insulation bricks made by these two methods, the crystal of fused mullite is larger than that of sintered mullite, and the thermal shock resistance is better than that of sintered products. Their high temperature performance mainly depends on the content of alumina and the uniformity of the distribution of mullite phase and glass phase. Mullite insulation bricks are mainly used for hot blast furnace top, blast furnace body and bottom, regenerator of glass melting furnace, ceramic sintering kiln, lining of petroleum cracking system, etc.
Therefore, when we choose mullite insulation bricks, we also need to consider the cost &performance of sintered mullite bricks and fused mullite bricks, and use mullite insulation bricks according to the specific kiln conditions.
