Silica bricks are acidic refractory with over 94% silica content anda bulk density of 2.38 g/cm3. They are resistant against acidic/alkalinecorrosion and coracidic sag aswel as hiah therma strenath.it has load softening temperature of 1620-1670ºC,which is stable in loncoperation at high temperature 600ºC and above, without crystallinetransformation. Low temperature expansionis coefficient.thermashock resistance is higher.
Silica bricks are mainly used for the partition wall of carbonizatiorand combustion chamber of coke oven, heat storaae chamber and slacchamber of steel blast furnace, even heat furnace, glass melting kilrand ceramic firing kiln, also used in the high temperature bearing parof hot blast furnace and acid blast furnace roof.
Characteristics of silica bricks
(1) High refractoriness under load. Coke oven silica bricks must withstand the dynamic load of the coal loading car on the furnace roof at high temperatures and must not deform during long-term use. Therefore, the refractoriness under load of coke oven silica bricks is required to be high.
(2) High thermal conductivity. Coke is made by heat transfer from coking coal in the carbonization chamber to the kiln wall of the combustion chamber. Therefore, the silica bricks used to build the combustion chamber wall should have a high thermal conductivity.
(3) Good thermal shock resistance. Since the coke oven needs to be loaded with coal and discharged periodically, the temperature of the silica bricks on both sides of the combustion chamber wall changes dramatically. Therefore, the coke oven silica bricks are required to have good thermal shock resistance.
(4) High temperature volume stability.
Physical and Chemical Specifications:
Specification |
GZ-96 |
GZ-95 |
GZ-94 |
Chemical composition(%) |
SiO2 |
>96 |
>95 |
>94 |
Fe2O3 |
≤1.0 |
≤1.2 |
≤1.4 |
Apparent Porosity (%) |
<22 |
<22 |
<22 |
Bulk density,g/cm3 |
≤2.34 |
≤2.34 |
≤2.34 |
Cold Crushing strength MPa |
>30 |
>30 |
>30 |
Refractoriness under Load (0.2MPa ºC) |
>1660 |
>1650 |
>1640 |
Main uses of silica bricks:
The mass fraction of SiO2 in silica bricks is not less than 94%. Although the refractoriness is not very high, the load softening temperature is relatively high, up to 1640-1680ºC, the high-temperature structural strength is large, and the stability is good when used for a long time above 600ºC, and it can resist the erosion of acidic slag. Therefore, it is currently mainly used for masonry of glass melting furnaces and coke ovens. Silica bricks for glass kilns are siliceous refractory products mainly made of scale quartz for masonry of high-temperature parts of glass tank kilns. The higher the SiO2content in the silica raw material, the higher the refractoriness of the product. Widely used in glass tank kilns and kiln roofs, tank walls and other parts
Silica bricks for glass kilns should have the following characteristics:
High-temperature volume stability, will not cause changes in the furnace body due to temperature fluctuations;
No pollution to glass liquid;
Chemical erosion resistance;
Low volume density.
The phase composition of silica bricks is mainly SiO2 crystals and a small amount of silicate crystals such as calcium silicate. There are many types of SiO2 crystals, including quartz, tridymite and cristobalite. The crystal phase composition of silica brick is (%): 30~70% of tridymite and 2 types of brick-type refractory materials for large thermal equipment, of which silica brick accounts for 60%~70%. Coke oven silica bricks are used to build the heat storage chamber, ramp, combustion chamber, carbonization chamber and furnace roof of the coke oven. Silica bricks are the main material for coke oven masonry, mainly used for building the combustion chamber, carbonization chamber, ramp, heat storage chamber wall and furnace roof of the coke oven, accounting for 60~70% of the total refractory bricks used in coke ovens.
Silica bricks are widely used in large blast furnace hot blast furnaces. The high temperature area of the hot blast furnace includes the upper part of the vault and the checker bricks, mainly the fuel combustion space and the surrounding area. The temperature in this area is always stable in the high temperature section, with small fluctuations, and is mainly built with silica bricks.
Product Packing and Delivery:
Wooden pallet size:930*930mm,Load weight of each pallet:1.5-2.0 Tons.
20 Foot Container can be loaded 25Tons,40 Foot Container can be loaded 28Tons.