Refractory Materials for Aluminum Furnaces

The insulation layer of an alumina rotary kiln is to lay a layer of refractory fiber felt on the kiln shell, and then lay diatomaceous earth, floating bead bricks, or lightweight clay bricks. Some now use lightweight refractory castables. The working lining of the prezone is constructed with clay bricks, and the high-temperature calcined zone is constructed with high alumina bricks or phosphate-bonded unfired high alumina bricks.

At present, unshaped refractory materials have been widely used in the aluminum industry, such as low-calcium aluminate refractory castables for the calcining zone, steel fiber-reinforced wear-resistant castables for the kiln mouth, kiln hood, kiln tail, and other parts.

The flash furnace installs heat-resistant steel anchors or ceramic anchors on the furnace shell, then lays a layer of 20mm thick refractory fiber felt, and finally pours 200-300mm thick refractory castables.

The working lining of the reverberatory furnace of the aluminum smelting furnace in contact with the aluminum liquid is generally built with high-aluminum bricks with an aluminum content of 80 to 85%. When smelting high-purity metallic aluminum, mullite bricks or corundum bricks are used. The combination of silicon nitride and silicon nitride bricks is used for the erosion and wear parts of the hearth slope such as scrap aluminum. The aluminum tank and aluminum outlet are severely corroded by molten aluminum. Generally, self-bonding or silicon nitride-bonded silicon carbide bricks are used, and zircon bricks can also be used as linings. Generally, clay bricks, clay refractory castables, or refractory plastics are used as linings, which do not come into contact with liquid aluminum.

The lining material of the induction furnace for smelting aluminum and aluminum alloys is generally high-aluminum dry ramming material, or silicon carbide is added to the alumina dry ramming material, which is less likely to cause leakage.