If the refractory bricks are damaged, it will not only affect the quality of the product, but also make the kiln lose its protection and must be shut down for maintenance. Once the kiln stops operating, it will cause serious economic losses to the enterprise. Understanding the cause of damage to refractory bricks can effectively extend their service life, thereby reducing the economic losses caused by shutdown of the kiln for maintenance.
Refractory bricks can help industrial kilns resist high-temperature corrosion and improve kiln performance and benefits. They are an indispensable part of high-temperature industrial kilns and the most important line of defense for kilns.
The reasons for the damage of refractory bricks are as follows:
1. The erosion and penetration of slag on the brick body
The erosion of refractory bricks by molten slag mainly includes three processes: penetration, dissolution, and erosion and wear. The erosion of refractory bricks by molten slag depends on the chemical composition of the slag and refractory materials, the operating temperature, and the melting point and fluid state of the slag, including the penetration of the dissolved slag into the refractory material, resulting in structural spalling.
2. Damage caused by thermal stress
Spalling is caused by uneven stress caused by refractory bricks. The reasons include: molten slag penetrates into refractory bricks to form a metamorphic layer, causing structural stress; temperature fluctuations in the kiln cause thermal stress; metal kiln shells cause mechanical stress; refractory bricks for a long time Creep stress generated at high temperature, etc.
Various stresses work together to cause cracks in the weak parts of the brick surface. The cracks continue to expand and penetrate each other to form cracks, and finally leave the brick body in a flaky or block form to form flaking, causing damage to the refractory brick.
3. Mechanical wear
The mechanical abrasion of refractory bricks mainly comes from high-speed steam stripping and flowing molten slag, which not only strengthens the chemical reaction between slag and refractory bricks, and removes the reaction products with low ash melting point from the surface of the brick, but also accelerates the deterioration of the brick body. , The spalling process of the cracked part.
The above are just the basic principles of refractory brick damage. In reality, the actual use of the kiln is different, and it may also cause different degrees of damage to the refractory bricks.
