An Introduction
High Alumina Bricks are commonly used refractory materials having the formula of Al2O3. They are alumina-silicate refractories developed using high-quality alumina or other raw materials. They can resist acid slag erosion owing to their neutral refractory property. In addition to this, they come with high thermal stability over 1770℃. Different types of bricks raw materials are available from bauxite having hydrated alumina mineral, sillimanite mineral as well as artificial raw materials.
Manufacturing Process of High Alumina Bricks
Silimanite, kyanite and andalusite are taken as mineral concentrates and added into the matrix in the presence of corundum powder. Sieve 90~95% chamotte for deironing and breaking to enhance the quality of the bricks. They are manufactured at high firing temperature from 1500~1600℃ temperature in the tunnel kiln
Properties of High Alumina Bricks
1) They come to the advanced refractory materials with higher refractoriness up to 1790℃ in comparison with the fire clay bricks.
2) They have higher refractoriness property that is maintained even under load as they come with higher Al2O3 content.
3) They contain SiO2 content to ensure to resist acid slag erosion.
4) They are yellowish white in color available in different sizes from 9 X 4.5 X 2.5 to 9 X 2.75 X 2.25 inches having 30 to 35 N weight.
5) They come with the compressive strength of 220 N/mm2.
6) They resist acid, alkali slags and washing erosion as they are neutral in nature
Applications of High Alumina Bricks
These bricks are widely used in the manufacturing of:
1) Air furnace
2) Boilers
3) Blast furnace
4) Electric furnace
5) Hot blast stove
6) Reverberatory furnace
7) Rotary kiln
In addition to the above, they can also be used as checker bricks and chock plug in heat accumulating systems and gating systems.