Applications Of Silica Bricks In Industrial Furnaces

Silica brick is one of the most commonly used refractories, with a history of 100years. Due to its high temperature strength, high softening temperature under load and good resistance to creep and acid slags, it is widely used in industrial furnaces such as coke ovens, glass furnaces and hot stoves of large blast furnaces. 

Silica brick is the main construction material for coke ovens, accounting for 60% to 70% of the total refractories. It is mainly used in the combustion chamber, carbonization chamber, ramps, the roof and the sidewall of the regenerator. Silica brick used in the coke ovens maily consists of tridymite. Since during the use it should withstand the dynamic load of the coal cars on the roof, coking coal is heated by the partition heat transfer and the wall of the combustion chamber is subjected to dramatic temperature change, it should have high softening temperature under load, high thermal conductivity, good thermal shock and volume stability. In order to increase the production capacity of modern large coke oven, it should have less residual quartz, higher density, thermal conductivity, high temperature strength and thermal shock. Therefore, high quality silica brick with high density, high purity and high thermal conductivity is under development to meet the needs. 

 

Since silica brick has low cost, high purity, high softening temperature under load, no contamination to glass and good resistance to some R2O gases and acid gas, it is widely used in the crown, hanging wall and the front/back wall. Silica brick used in glass furnaces mainly consists of cristobalite and the SiO2 should be controlled well. For large glass furnaces and oxy-fuel glass furnaces, common silica brick cannot meet the requirement of the operation environment, so high quality silica brick with high purity and high resistance to creep and corrosion is used. 

 

Silica brick is widely used in the hot stove of the large blast furnace. The high temperature areas of the hot stove include the doom and the upper part of the checker work. Silica brick used in the hot stove of the large blast furnace mainly consists of tridymite and has the following features: 

1)have good volume stability and resistance to high temperature creep and can be used continuously for one or even two blast furnace campaigns;

2)Have good thermal shock resistance and good adaptation to the temperature changes of the hot stoves;

3)Have better resistance to chemical attack than fireclay brick and high alumina brick.

With the development of the ironmaking technology, the hot stove is subjected to higher temperature and the requirement is more demanding. 

 

With the development of high temperature industries, the requirement for the silica brick is more and more demanding. In order to meet the need, silica brick with better performance is under development.