Zirconium bricks are mainly used in which kilns?

Zirconium bricks, especially fused zirconia-corundum bricks (AZS bricks) and high-zirconia bricks, play a crucial role in high-temperature industrial kilns due to their excellent erosion resistance, high-temperature stability, and low pollution. Their application is primarily in the glass industry, but extends to special applications in environmental protection, metallurgy, and chemicals.

Glass Industry Kilns (Core Application)

Glass melting furnaces are the most widely used application of zirconium bricks, accounting for over 90%. Based on the ZrO₂ content, different types of zirconium bricks are precisely used in key parts of the kiln:

AZS-33# bricks (ZrO₂ approximately 33%): Good castability, mainly used in the upper structure of the kiln, working pool walls, and material channels—areas where there is no direct contact or less erosion.

AZS-36# bricks (ZrO₂ approximately 36%): Superior erosion resistance, suitable for hot spots with high glass flow rates and temperatures, such as the walls of the molten glass pool.

AZS-41# brick (ZrO₂ approximately 41%): Offers the best corrosion resistance among zirconium-corundum bricks, used in the most critical parts of the kiln, such as flow channels, kiln sills, and feed inlet corners.

High-zirconium brick (ZrO₂ > 80%): Exceeds AZS-41# in performance, exhibiting extremely low corrosion rates above 1600℃. Used in critical parts such as the walls and flow channels of long-life kilns in high-end production lines for photovoltaic glass and LCD glass, with a service life several times that of traditional materials.

Special High-Temperature Treatment Kilns

Fly Ash Vitrification Electrofusion Kilns: When processing waste incineration fly ash, traditional materials are easily corroded by CaO and chloride ions. Electrofused Z80 high-zirconium bricks exhibit excellent corrosion resistance (corrosion rate of only 0.6 mm/month, far superior to AZS bricks’ 1.6 mm/month), making them ideal for such demanding conditions.

Electronic and Specialty Glass Furnaces: High-zirconium bricks, due to their extremely low contamination of molten glass and near-zero bubble formation rate, are used in production lines for high-quality glass such as LCD glass and borosilicate glass.

Other Industrial Furnaces

Steel and Iron Metallurgy: Used in ladle slides, RH furnace immersion tubes, etc., to resist erosion and corrosion from molten steel.

Chemical Industry: As linings for coal gasification furnaces, resistant to acidic media and high-pressure environments.

Non-ferrous Smelting: Used as lining material in some high-temperature, highly corrosive areas.