PRODUCT DESCRIPTION

Free Calcium Silica Brick

Free calcium silica bricks are ultra-high-purity, advanced refractory materials specifically developed to overcome the weaknesses of traditional silica bricks. While conventional silica bricks use calcium oxide as a mineralizer during production, free-calcium silica bricks reduce calcium from their chemical formulation, yielding a SiO₂ purity exceeding 99%. Designed with optimized particle distribution and rigorous high-temperature sintering, these bricks feature high density, low residual quartz, and a mineral structure free of calcium based flux phases. They are the premier choice for modern, aggressive high-temperature environments.

Advantages

l  Superior Alkali Corrosion Resistance: Standard silica bricks react with alkali vapors to form a low-melting calcium-silicate liquid phase that causes severe erosion. Extremely low calcium content allows these bricks to withstand heavy vapor attacks without structural deterioration.

l  Low Thermal Expansion at High Temps: They display a near-zero thermal expansion curve at working temperatures. This allows them to stay dimensionally stable without shrinking or cracking over long-term operations.

l  Excellent Hot Repair Performance: Their unique mineral profile gives them superb thermal shock resistance. Operators can install them directly into a hot furnace during hot repairs without facing the risks of explosions or spalling.

l  Zero Product Contamination: Maintaining a very low iron and chemical flux index prevents any discoloration or contamination of high-end melts like optical or colorless glass.

l  No Expansion Joint Requirements: Because they feature a near-zero expansion profile during hot installations, they eliminate the need for complex expansion joints. This streamlines the masonry process and ensures tight, leak-free sealing.

Applications

1. Oxy-Fuel Combustion Glass Furnaces

• Superstructures and Crowns: Oxy-fuel furnaces generate much higher concentrations of water vapor and volatile alkali vapors (NaOH, KOH) than traditional air-fuel furnaces. Free-calcium bricks are essential here to prevent catastrophic crown erosion.

• Ports and Tongue Arch: Frequently utilized in critical zones of high-load tank kilns, including bottle glass, float glass, and sodium silicate glass furnaces.

2. High-Temperature Furnace Hot Repairs

• Online Repair Bricks: Specially designated as hot repair elements for repairing damage on furnace crowns, arches, burner blocks, and walls without stopping the furnace or dropping the system temperature.

3. Specialty Metallurgy & Chemical Kilns

    ·   Coke Oven Carbonization Chambers: Used as liners and walls for heavy-duty coking chambers. Eliminates calcium flux to prevent reactions with coal ash and volatile gases. High refractoriness under load prevents wall deformation during heavy             coke pushing. Excellent resistance to coal ash, sulfur, and acidic gas corrosion. High thermal conductivity shortens the coking cycle and saves energy.

• Acidic Melting Environments: Used in lining high-temperature zones that experience volatile acidic gases or direct contact with highly acidic slags, ensuring extended equipment campaigns.

   TECHNIQUE DATA