The mechanism of preventing acid slag corrosion of silicon brick in coke oven is mainly based on the comprehensive advantages of its chemical composition, mineral composition and physical properties. The following is a concrete analysis:

I. Compatibility of chemical components with acidic slag

The main component of silica brick is silica (SiO₂), and its content is usually above 93%. The main component of acid slag is also SiO₂, so silica brick and acid slag are similar in chemical properties and have good compatibility. When acid slag comes into contact with silicon brick, it is difficult for acid slag to chemically attack silicon brick because their main components are the same.

II. 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. Tridymite and FangShi Ying have stable crystal structures, high refractoriness and corrosion resistance. Tridymite, in particular, has low true density, low linear expansion rate, good thermal stability and strong slag erosion resistance. The existence of these mineral components makes the silicon brick keep its structure stable in high temperature environment, and it is not easy to be corroded by acid slag.

III. Protective effect of high temperature performance

The load softening temperature of silicon brick is relatively high, generally above 1620℃, which is close to its refractoriness. This means that in the high temperature environment of coke oven, silicon brick can maintain high structural strength and is not easy to deform or soften, thus effectively resisting the corrosion of acid slag.

IV. Volume stability

Silicon brick has good volume stability at high temperature. Although a certain volume expansion will occur during the baking process, this expansion can be controlled and the volume will remain basically stable after long-term use at high temperature. This volume stability is helpful to reduce the contact area between brick and acid slag and reduce the possibility of erosion.

V. Air tightness and structural strength

Silicon brick masonry has good air tightness and structural strength. This characteristic can effectively prevent acid slag from penetrating into the brick body, thus reducing erosion. Even in high temperature environment, silicon brick can maintain high structural strength and further enhance its corrosion resistance.

VI. Corrosion resistance to specific oxides

Silicon brick has good corrosion resistance to some oxides (such as Fe₂O₃ and CaO). These oxides may exist in acid slag, but silicon brick can effectively resist their erosion, thus further enhancing its ability to resist acid slag erosion.

To sum up, silicon brick can effectively prevent the corrosion of acid slag in coke oven through its advantages in chemical composition, mineral composition, high temperature performance, volume stability, air tightness and structural strength, thus prolonging the service life of coke oven.