Refractories for Alining
January 20, 2021
In the world non-ferrous metal production, the annual output of aluminum ranks first, far more than other non-ferrous metals. The aluminum industry consumes much more refractories each year than copper, lead and zinc smelters. The production method of metal aluminum is a fixed two-step method: the first step is to produce alumina from bauxite by wet method, and in the second step, aluminum is obtained by molten salt electrolysis with industrial alumina as raw material. The high temperature kiln used in the production process includes rotary kiln, molten salt electrolytic tank, molten aluminum furnace and so on.
The refractory consumption of aluminum industrial furnace is very large. As a result, the alkali material in the Al₂O₃ material is especially serious to the refractory of rotary kiln. in the process of smelting aluminum, even at a lower temperature, metal aluminum still has a strong permeability. once it seeps into the brick, it will react with the SiO₂ in the brick, reduce the Si, destroy the structure of the refractory, and make the lining produce metamorphic layer, loose, peeling and damaged. Response :3SiO₂+4Al---2Al₂O₃+3Si。
Therefore, refractory materials containing SiO₂ should not be used as furnace materials for metal aluminum smelting equipment. Therefore, the general aluminum industry furnace refractory, in addition to high aluminum brick, commonly used carbon products.