What is the Alumina Content of High Alumina Bricks?

High-alumina brick refractory brick is a shaped refractory material formed and calcined from high-alumina bauxite or other raw materials with high alumina content. It is an indispensable raw material for lining high-temperature kilns. It has high thermal stability, the refractoriness can reach above 1770℃, and it has good slag resistance. The aluminum content of high-alumina refractory bricks has different aluminum content according to the different uses, but only when the alumina content reaches 48% or more can it be called high-alumina bricks.

High alumina refractory bricks can be divided into first-grade high-alumina bricks, second-grade high-alumina bricks, third-grade high-alumina bricks, special-grade high-alumina bricks, corundum bricks, low-creep high-alumina bricks, and dense High alumina bricks, aluminum silicon carbide high alumina bricks and andalusite high alumina bricks, the following is the introduction of the aluminum content of each high alumina brick:

1. Three-grade high alumina bricks. The third-grade high-alumina brick refers to the refractory brick with an alumina content between 48%＜AL2O3＜60%.

2. Secondary high alumina brick. Secondary high alumina bricks refer to refractory bricks with an alumina content of 60%≤AL2O3＜70%.

3. First-grade high alumina brick. First-grade high alumina bricks refer to refractory bricks with an alumina content of 70%＜AL2O3≤75%.

4. Super high alumina brick. Super high alumina bricks refer to refractory bricks with an alumina content of 75%＜AL2O3≤85%.

5. Corundum brick. Corundum brick refers to a refractory brick with an alumina content of more than 90%. It is a high-grade refractory material and is mainly used in some important parts of high-temperature kilns.

6. Low creep high alumina brick. Low-creep high-alumina bricks are a kind of high-alumina refractory bricks, which are improved on the basis of commonly used high-alumina refractory bricks. In the original high-alumina brick production formula, refractory materials with low creep rate are added, which is reasonable Control molding and firing, so that the high alumina brick has a certain low creep rate, and its alumina content is also above 48%.

7. Dense high alumina brick. The difference between dense high-alumina bricks and ordinary high-alumina bricks is that they have low pores, are denser, have a longer service life, and have stronger erosion resistance. Compared with ordinary refractory bricks, dense high alumina bricks need to add a certain proportion of burnt gems or kyanite.

8. Andalusite high alumina brick. Andalusite refractory bricks use andalusite as raw material, add sillimanite powder, mullite powder, and other powders, add binders according to the proportion, and strictly control the particle size, grade, and impurities such as TiO2 and R2O of the raw materials. It is fired at high temperatures after smelting, molding, and drying, which can meet the needs of different parts and working environments of modern blast furnace hot blast stoves and is of great significance for improving the service life of blast furnace hot blast stoves.

High alumina refractory bricks are mainly used in the construction of ceramic frit kilns, sodium silicate kilns, glass kilns, blast furnaces, hot blast furnaces, electric furnace roofs, blast furnaces, reverberatory furnaces, rotary kiln linings, and other high-temperature kilns. , The refractoriness and compressive strength of refractory bricks with different aluminum content are different. When we choose, we must choose according to the occasion of use.