Along with spalling, what is another main cause of refractory deterioration?

The correct answer is slagging because it refers to the formation of a solid or semi-solid material that forms as a byproduct of the combustion process in high-temperature environments, such as furnaces or boilers. When molten slag comes into contact with refractory materials, it can cause significant deterioration due to its corrosive nature. Slag can infiltrate the porous structure of the refractory, leading to chemical reactions that weaken the material and ultimately result in its breakdown.

This is a critical aspect of maintaining the integrity of refractories, as slagging can compromise the thermal insulation properties and structural support they are meant to provide in high-temperature operations. Effective management of slag formation and minimizing its contact with refractories are essential for prolonging their lifespan and maintaining operational efficiency.