Typical aluminum smelting furnaces are lined with refractory materials, usually made of high-aluminum refractory materials, Si3N4 combined with SiC refractories. When a high-aluminum refractory material is used, since SiO2 and impurities such as Fe2O3 in the refractory material are reduced to Si and Fe and melted into the metal aluminum, it is difficult to obtain high-purity metal aluminum. When Si3N4 is combined with SiC refractory, although the impurity can be reduced into the metal aluminum to obtain higher purity metal aluminum, since the Si3N4 combined SiC material contains Si component, metal aluminum still exists. The danger of picking up Si in refractory materials. Therefore, in order to obtain extremely high purity aluminum, a refractory material which does not introduce impurities is required. According to the chemical principle, in the existing refractory products, it is considered that the corundum refractory material produced by using the same raw material of metal aluminum, Al2O3, as the raw material can meet the above requirements. Or the plate-like alumina is made of raw materials and is formulated with an appropriate amount of alumina micropowder. The key technology is to use a pure matrix to realize the self-cleaning structure of the alumina to obtain high strength without melting impurities into the metal In aluminum.
Application of special corundum brick in preparing high purity aluminum melting furnace
In addition, since the aluminum factory has a large temperature change during the aluminum smelting process, the lining refractory material used for the aluminum smelting furnace should have the characteristics of no peeling off and good thermal shock resistance in the case of rapid temperature change. It can be seen that a corundum refractory material having high thermal shock resistance without intrusion of metal aluminum into the impurity component is an important refractory material for selecting high-purity aluminum. The content of Al2O3 in the corundum refractory material is more than 94%, and the thermal shock resistance is high.
Application of special corundum brick in preparing high purity aluminum melting furnace
When A brick (94% Al2O3 content) was used as the lining of the smelting furnace of 99.99% Al, it was found that the impurities in the prepared metal aluminum were significantly reduced, and the impurities were less than the SiC bricks combined with Si3N4. Further research has shown that the use of 94% Al2O3 corundum brick smelting furnace for the production of 99.999% and 99.9999% Al has been successful. It can be seen that the special corundum brick which is densely bonded and has a dense structure and an Al2O3 content of more than 94% is an optimum refractory material for producing high-purity metal aluminum.