The high alumina brick is one kind refractory material, the main content of this refractory brick is Al2O3.
High Alumina Refractory Bricks Introduction
High alumina refractory brick is a kind of alumina-silicate refractory material with content of alumina oxide more than 48% Al2O3. It is calcined and formed by the raw material of banxite or the material with high content of AL2O3. High thermal stability, the refractoriness is more than 1770℃. Good slag resistance, used for the liner of masonry steel-making electric stove, glass furnace and cement revolver.
High Alumina BricK Specification
Based on the different Al2O3 content, High Alumina Bricks can be divided into Three Grades in China.
Grade I :content more than 75% Al2O3.
Grade II: content with 60~75% Al2O3 .
Grade III: Content with 48~60% Al2O3.
High Alumina Refractory Bricks
The manufacturing process of the alumina is similar to the manufacturing process of clay brick. The difference is that the clinker proportion in ingredients is relatively high, reach to 90%~95%, the clinker needs to be sorted and screened for iron removal before crushing, the firing temperature is high. For example, the I and II grade high alumina bricks are usually burned at 1500~1600 with tunnel kiln.High Alumina Bricks Composition:
According to the different requirement of resource condition and products requirement , can adopt the following kinds of raw material: bauxite made of hydrated alumina mineral (monohydrate, gibbsite), sillimanite mineral (including kyanite, andalusite and sillimanite) and synthetic raw materials (commercial alumina, synthetic mullite and fused alumina). There are abundant quality resources of high alumina bauxite in China. RS Company in China has the dominant advantage on manufacturing high quality high alumina bricks.
High Alumina Refractory Bricks
Item
Index
LZ-48
LZ-55
LZ-65
LZ-75
LZ-80
AL2O3 (≥%)
48
55
65
75
80
Fe2O3 (≤%)
2.0
2.0
2.0
2.0
1.8
Refractoriness Under Load （0.2Mpa）≥ ℃
1420
1450
1500
1520
1530
Reheating Linear Change
1500℃*2h
–
0.1-0.4
0.1-0.4
0.1-0.4
0.1-0.4
1450℃*2h
0.1-0.4
–
–
–
–
Apparent Porosity (≤%)
22
22
23
23
22
Cold Crushing Strength ≥ (MPa)
35
40
45
50
55
Bulk Density (g/c m3) ≥
–
–
–
–
–
High Alumina Bricks Properties
A: Degree of fire resistance: The refractoriness of high alumina bricks are higher than clay brick and semi-silica brick, reach to 1750~1790, belong to high-duty refractory.
B: Refractoriness under load
Because the high content of AL2O3 in high alumina products and low impurity which form little fusible vitreum body, so the refractoriness under load is higher than the clay brick, but because mullite crystal does not form network structure, their refractoriness under load is lower than silica bricks.
C: Resistance to Slag
The high alumina bricks have more Al2O3 and belong to neutral refractory, it can resist to the acid and basic slag erosion. Owing to it has SiO2, so the ability of acid resistance is better than the ability of resistance to acid slag.
High Alumina Brick Application
The high alumina bricks can be applied to build blast furnace, hot blast stove, electric furnace roof, blast furnace, reverberatory furnace, lining of rotary kiln. In addition, the high alumina brick is widely used in checker bricks of heat accumulating type, chock plug for gating system, nozzle brick and so on.
High Alumina refractory Manufacture
Zhengzhou Rongsheng Kiln Refractory Material Co., Ltd is specialized in producing high quality high alumina refractory bricks for many industries.
