- Time:Sep 07, 2023
Choosing the right refractory brick for different parts of a blast furnace requires considering several factors such as the operating conditions, temperature, chemical environment, mechanical stresses, and specific requirements of each furnace zone. Here are some general guidelines to help with the selection:
1. Hot Blast Stove and Bustle Pipe: These zones experience high temperatures and severe thermal cycling. Refractory bricks with high thermal shock resistance, thermal conductivity, and resistance to abrasion and erosion are required. Alumina-silica or alumina-magnesia bricks are commonly used in these areas.
2. Bosh and Stack: These sections are exposed to intense heat, chemical reactions with molten iron, and mechanical stresses. High-density, high-alumina, or mullite-based bricks are suitable for their excellent thermal shock resistance, corrosion resistance, and good load-bearing capacity.
3. Belly and Hearth: These regions encounter molten metal and slag, causing chemical attacks and wear. Carbon-containing bricks, such as magnesia-carbon or alumina-magnesia-carbon bricks, are preferred due to their resistance to slag penetration, thermal spalling, and thermal shock.
4. Tuyere and Tuyere Cooler: Tuyeres endure high temperatures, combustion gases, and mechanical stress from gas injection. Silica-based or high-alumina bricks with good thermal conductivity, low porosity, and resistance to erosion and oxidation are typically used. For tuyere coolers, water-cooled copper or ceramic components are often employed.
5. Hearth Bottom: The hearth bottom is in direct contact with molten iron and slag, experiencing severe wear and thermal shock. High-quality magnesia-based bricks with excellent corrosion resistance and thermal shock resistance are commonly used in this area.
6. Upper Stack and Throat: These areas require bricks with good thermal insulation properties to minimize heat loss. Insulating firebricks (IFBs) or lightweight refractory bricks made from materials like silica, alumina, or mullite are suitable for these zones.
7. Expansion Joints and Seals: Use flexible refractory materials, such as ceramic fibers or ceramic rope, to accommodate thermal expansion and provide effective seals between different refractory sections.
It is essential to consult with refractory experts or manufacturers to select the most appropriate refractory bricks for each specific blast furnace application. Factors like refractory brick quality, installation techniques, and ongoing maintenance should also be considered to ensure optimal performance and extended service life of the refractory linings in the blast furnace.
