Alumino-silicate bricks, integral to the refractory linings in the metallurgical industry, are engineered to withstand extreme temperatures and corrosive environments. These bricks, varying in alumina (Al₂O₃) content from 30% to 85%, are designed to meet the specific demands of different metallurgical processes, ensuring durability, efficiency, and cost-effectiveness.

Composition and Classification

Low-Alumina Bricks (30-45% Al₂O₃)

Al₂O₃ Content: 30-45%
SiO₂ Content: 55-70%
Application: Used in areas with lower thermal requirements, such as the walls and hearths of furnaces.

Medium-Alumina Bricks (45-60% Al₂O₃)

Al₂O₃ Content: 45-60%
SiO₂ Content: 40-55%
Application: Suitable for areas with moderate thermal and mechanical stress, such as ladles and lining of heating furnaces.

High-Alumina Bricks (60-85% Al₂O₃)

Al₂O₃ Content: 60-85%
SiO₂ Content: 15-40%
Application: Ideal for high-stress areas like blast furnaces, steel ladles, and reactors, where excellent thermal resistance and stability are required.

Physical and Thermal Properties

Property	Low-Alumina Bricks	Medium-Alumina Bricks	High-Alumina Bricks
Cold Crushing Strength (CCS)	30-40 MPa	40-60 MPa	60-90 MPa
Refractoriness Under Load (RUL)	Up to 1350°C	Up to 1500°C	Up to 1650°C
Apparent Porosity	20-25%	18-22%	15-20%
Thermal Conductivity	1.0-1.2 W/m·K	1.2-1.4 W/m·K	1.4-1.6 W/m·K

Advantages in Metallurgical Applications

Thermal Stability: High alumina content ensures superior performance at elevated temperatures, crucial for metallurgical processes.
Mechanical Strength: Enhanced CCS values provide resilience against mechanical wear and tear.
Corrosion Resistance: Alumino-silicate bricks offer excellent resistance to slag and chemical attack, prolonging the lifespan of furnace linings.
Energy Efficiency: Optimal thermal conductivity minimizes heat loss, improving energy efficiency in metallurgical operations.

Applications in the Metallurgical Industry

Blast Furnaces: Linings made from high-alumina bricks protect against high temperatures and chemical reactions.
Steel Ladles: Medium to high-alumina bricks ensure durability and thermal efficiency during steel refining and transportation.
Heating Furnaces: Low to medium-alumina bricks provide effective insulation and withstand the cyclical heating processes.

By selecting the appropriate alumino-silicate bricks based on alumina content and specific property requirements, metallurgical plants can optimise performance, extend refractory life, and enhance overall operational efficiency.

Fuels

Ferrous Industry

Non Ferrous Industry

Coke Oven Industry

Alumino-silicate bricks, essential for the construction and maintenance of coke ovens, are engineered to endure the harsh thermal and chemical environment inherent to coke production. These bricks, with alumina (Al₂O₃) content ranging from 30% to 85%, are designed to meet the specific demands of coke ovens, ensuring durability, efficiency, and cost-effectiveness.

Composition and Classification

Low-Alumina Bricks (30-45% Al₂O₃)

Al₂O₃ Content: 30-45%
SiO₂ Content: 55-70%
Application: Used in areas of the coke oven where thermal stresses are relatively lower, such as the outer linings and insulation layers.

Medium-Alumina Bricks (45-60% Al₂O₃)

Al₂O₃ Content: 45-60%
SiO₂ Content: 40-55%
Application: Suitable for zones with moderate thermal and mechanical stress, such as the upper regions of the oven walls and some parts of the roof.

High-Alumina Bricks (60-85% Al₂O₃)

Al₂O₃ Content: 60-85%
SiO₂ Content: 15-40%
Application: Ideal for high-stress areas like the combustion chamber linings and lower regions of the oven walls, where high thermal resistance and stability are crucial.

Physical and Thermal Properties

Property	Low-Alumina Bricks	Medium-Alumina Bricks	High-Alumina Bricks
Cold Crushing Strength (CCS)	25-35 MPa	35-55 MPa	55-80 MPa
Refractoriness Under Load (RUL)	Up to 1350°C	Up to 1500°C	Up to 1650°C
Apparent Porosity	20-26%	18-23%	15-20%
Thermal Conductivity	1.1-1.3 W/m·K	1.3-1.5 W/m·K	1.5-1.7 W/m·K

Advantages in Coke Oven Applications

Thermal Stability: High alumina content ensures superior performance at elevated temperatures, critical for the efficient production of coke.
Mechanical Strength: Enhanced CCS values provide resilience against the mechanical wear and thermal cycling common in coke oven operations.
Chemical Resistance: Alumino-silicate bricks offer excellent resistance to the corrosive effects of coal ash and other by-products of coke production.
Energy Efficiency: Optimal thermal conductivity minimizes heat loss, improving energy efficiency and operational cost-effectiveness in coke ovens.

Applications

Combustion Chambers: High-alumina bricks are essential for the linings of combustion chambers, ensuring durability under high temperatures and reducing downtime due to maintenance.
Oven Walls: Medium to high-alumina bricks provide reliable performance for the inner walls, enduring thermal stress and mechanical wear.
Oven Roofs: Medium-alumina bricks are used in the roof sections, providing effective thermal insulation and resistance to thermal shock.
Flue Walls: Low to medium-alumina bricks are utilized in the flue walls, offering essential protection and insulation against moderate thermal and chemical stresses.

By selecting the appropriate alumino-silicate bricks based on alumina content and specific property requirements, coke plants can optimize performance, extend refractory life, and enhance overall operational efficiency.