Aluminum Smelting Furnace and Holding Furnace Refractory

Aluminum Smelting Furnace and Holding Furnace Description

Gas-combustion or oil-combustion fixed or tilting reverberators are usually used for aluminum ingots and scrap aluminum melting and alloying, sometimes, resistance reverberator or induction crucible furnace are also adopted.

Although the temperature of aluminum liquid and aluminum alloy is only 700~800℃, magnesium, silicon, manganese and other element in aluminum and aluminum alloys are very active, easy to react with some components in refractory material and cause refractory damage. The main damage mechanisms of aluminum smelting furnaces are:

1. Aluminum liquid has very low viscosity, is easy to permeate into refractory material.
2. Some alloy elements in aluminum and its alloys have very strong reduction ability, their reduction-oxidization reaction is strong heat release reaction. Some alloy elements such as Mg have very high vapor pressure, their vapor is more liable to penetrate into refractory material and then be oxidized, finally cause the metamorphism , structure looseness and damage of refractory material.
3. During large scale aluminum smelting furnace working, continuously added aluminum ingots and alloy will have great impaction and abrasion to furnace inlet and furnace bottom.
4. The addition of aluminum ingots, the discharge of aluminum liquid and temperature fluctuation in furnace can do thermal shock damage to refractory lining.

Aluminum Smelting Reverbertator Refractories

Aluminum smelting reverbertator refractories should resist aluminum liquid and magnesium vapor infiltration, have excellent abrasion resistance and thermal stress impaction, etc. Furnace lining where contact with aluminum liquid usually adopts high alumina bricks containing 80%~85% of Al2O3. For high purity aluminum smelting, corundum bricks or mullite bricks are usually adopted. At furnace bed slope and scrap aluminum feeding parts, where corrosion and abrasion is frequently happened, silicon nitride bonded silicon carbide bricks are often used. At aluminum runner and aluminum tapping hole, aluminum scouring is severe, so self bonded or silicon carbide bonded silicon carbide bricks are adopted, zircon bricks are also used for the masonry of inner lining. For furnace lining, where don’t contact with aluminum liquid, clay bricks, fireclay castable or plastic refractory are usually used. The inner lining of aluminum running trough usually adopts silicon carbide bricks or fused foam silica precast blocks.

With the enlargement aluminum smelting furnace and the strengthening of smelting, high strength anti-aluminum permeation castable which has excellent permeation resistance, abrasion resistance and thermal impaction resistance are widely used in aluminum smelting furnace.

High Strength Anti-Aluminum Permeation Castable