The chemical composition of silicon brick has many advantages, which makes it show excellent performance in high temperature industry, especially in preventing acid slag corrosion in coke oven. The following are the specific advantages of its chemical composition:

I. High silica content

The main component of silicon brick is silicon dioxide (SiO₂), and the content is usually above 93%. High-purity SiO₂ gives silicon bricks the following advantages:

Strong corrosion resistance of acid slag: SiO₂ is similar to the main components of acid slag in chemical properties and has good compatibility, which can effectively resist the chemical corrosion of acid slag.

High fire resistance: the high melting point of SiO₂ makes the fire resistance of silicon brick usually between 1690℃ and 1750℃, which can remain stable in high temperature environment.

High high-temperature strength: the silica brick with high SiO₂ content has a high load softening temperature at high temperature, generally ranging from 1620℃ to 1670℃, and can withstand the mechanical load at high temperature.

II. Low impurity content

The impurity content of silicon brick is low, especially the contents of impurities such as Al₂O₃, KO and Na₂O are strictly controlled. These impurities will reduce the refractoriness and corrosion resistance of refractories, so silica bricks with low impurity content have the following advantages:

Improve the fire resistance: reducing impurities can avoid the formation of low melting point compounds, thus improving the fire resistance of silicon bricks.

Enhance corrosion resistance: low impurity content reduces the possibility of chemical reaction with acid slag, and further enhances the corrosion resistance of silicon brick.

III. Advantages of mineral composition

The mineral composition of silica brick mainly includes tridymite, cristobalite and a small amount of residual Shi Ying and glass phase. These mineral compositions have the following characteristics:

Tridymite content is high: tridymite has the lowest density, high load softening temperature, good thermal conductivity and little volume change at high temperature. Silicon bricks with high tridymite content have better corrosion resistance and volume stability.

Fang Shiying and residual Shi Ying: The existence of Fang Shiying and a small amount of residual Shi Ying further enhances the high temperature performance and corrosion resistance of silicon bricks.

IV. Chemical stability

Silicon brick belongs to acid refractory material and has good resistance to acid slag and gas. Its chemical stability is mainly reflected in:

Corrosion resistance of acid slag: In the coke oven, silicon brick can effectively resist the corrosion of acid slag and maintain structural stability even in high temperature environment.

Resistance to specific oxides: Silicon brick has good resistance to CaO, FeO, FeO and other oxides, which further enhances its stability in complex chemical environment.

V. Positive effects of residual expansion

In the process of high temperature firing, silicon bricks will expand to a certain extent, and this residual expansion will make the gaps between bricks close, thus ensuring the air tightness and structural strength of masonry. This plays an important role in preventing acid slag from penetrating into the brick body.

To sum up, the high SiO₂ content, low impurity content, mineral composition advantages and chemical stability of silicon brick can effectively prevent the corrosion of acid slag in coke oven, and at the same time, it has excellent properties such as high