Factors Affecting the Service Life of Gasifier Refractory Bricks

In actual production operations, the factors that affect the service life of refractory bricks used in gasifiers can be divided into three categories: thermal stress shear extrusion, ash washing, and chemical reaction erosion.

1. Thermal stress shear extrusion

During the startup, shutdown, and drying process of the gasifier, due to the different temperature rises and cooling rates of the refractory bricks during the heating or cooling process of the gasifier, relative displacement occurs. The thermal expansion of the refractory bricks causes shearing and extrusion between the refractory bricks, causing surface cracks in the refractory bricks and even local surface peeling. These cracks provide pathways for the penetration of molten ash.

2. Molten ash erosion

During the operation of the gasifier, a large amount of high-temperature molten ash and slag carried by high-speed airflow cause strong wear and erosion on the surface of the refractory bricks, causing the surface to gradually wear and become thinner.

3. Chemical reaction corrosion

During the operation of the gasifier, impurities such as liquid silica, alumina, titanium oxide, potassium oxide, and sodium oxide in the high-temperature molten ash enter the depth of the refractory bricks through the cracks and cracks on the surface of the refractory bricks and pass through the pores of the refractory bricks. Penetrates into the interior of the refractory bricks. Low melting point materials gradually form chemical reactions with the refractory brick body, reducing the strength, hardness, and high-temperature resistance of the refractory bricks.