Lightweight high-alumina bricks
Product introduction
Lightweight high-alumina bricks, also known as high-alumina insulation bricks, are lightweight refractory materials with an alumina content of more than 484.
Volume density: generally between 0.4 and 1.35 g/cm3123.
Porosity: usually 66% to 733.
Compressive strength: in the range of 1 to 8 MPa123.
Thermal shock resistance: due to factors such as high alumina content and special pore structure, it has good thermal shock resistance and can withstand rapid changes in temperature123.
Thermal conductivity: low, generally 0.291 to 0.582W/(m・K) at 1350℃, with good thermal insulation performance3.
Production process: High-alumina bauxite clinker is usually used as the main raw material, with a small amount of clay added. After grinding, it is made into a slurry by gas generation or foaming method, then cast and formed, and finally fired at a high temperature of 1300-1500℃. Sometimes industrial alumina is used to replace part of the bauxite clinker124.
Application field
Metallurgical industry: used as the insulation layer of metallurgical furnaces, such as the insulation part of the lining of blast furnaces, electric furnaces, converters, etc., which can reduce heat loss and improve energy utilization. It can also be used for the lining and insulation layer of kilns such as heating furnaces and soaking furnaces.
Mechanical industry: In forging heating furnaces, heat treatment furnaces and other equipment, as lining and insulation materials, it helps to maintain uniform temperature in the furnace, reduce energy consumption, and improve heat treatment quality.
Ceramic industry: It is a common insulation material for ceramic kilns, such as tunnel kilns and shuttle kilns. It can provide a stable temperature environment for the ceramic firing process, while reducing heat dissipation to the outside of the kiln and saving energy.
Chemical Industry: Lining and insulation layers of various high-temperature reaction furnaces, cracking furnaces, gasification furnaces, etc. used in the chemical industry can resist certain chemical erosion and ensure the thermal insulation performance and operational safety of the equipment.
| Ingredients | Description |
| High alumina clinker | Provides high content of alumina, which is the main component to ensure the refractory performance and high
temperature stability of lightweight high-alumina bricks, and provides products with high refractoriness, mechanical strength and other properties |
| Clay | As an auxiliary raw material, it plays a role in binding and plasticization, which helps the molding of the blank. It can react with other components at high temperatures to affect the microstructure and performance of the product |
| Industrial alumina | Industrial alumina will be used to replace part of the alumina clinker in some products, which can further increase the alumina content, optimize the high temperature performance of the product, and improve the density, strength and other properties of the product |
| Gas generating agent or foaming agent | Used in the preparation process of gas generation method or foam method, it is used to generate a large number of evenly distributed bubbles in the mud to form a porous structure, thereby reducing the volume density of the product and improving the thermal insulation performance
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| High alumina brick grades | Aluminum carbide (Al₂O₃) content |
| Special high alumina bricks | 75%＜Al₂O₃≤85% |
| First-grade high alumina bricks | 70%＜Al₂O₃≤75% |
| Second-grade high alumina bricks | 60%≤Al₂O₃＜70% |
| Third-grade high alumina bricks | 48%＜Al₂O₃＜60% |
| Corundum bricks | Al₂O₃≥90% |
