Aluminum Oxide Manufacturing Process

Raw Materials of Aluminum Oxide

1. Alumina, also called bauxite: the main material for smelting brwon fused alumina, monocrystalline alumina and microcrystalline alumina. Main composition are Al₂O₃•3H₂O and Al₂O₃•H₂O, also mixted with opal, hematite, and goetite. The main quality requirement for alumina are chemical composition, dehydration, melting point and fragment. 

2. Carbon: the reductant in smelting aluminum oxide. Oil and anthracite are commonl used. Quality should be strictly controlled in chosing process.

3. Alumdum: the main material for smelting white fused alumina, pink fused alumina, zirconia alumina. It is a kind of white powder, with Al₂O₃ as its main gredient and melting temperature reaching above 2000℃. 

4. Pyrite (FeS₂): material for producing momocrystalline alumina.

5. Scrip iron: working as the diluent and clarifiant in smelting brown fused alumina, diluting the concentration of ferrosilicon alloy. Steel scrap and cast iron are commonly used.

Manufacturing Process

Aluminum oxide manufacturing process mainly includes electric furnace smelting, cooling and granulating. 

Brown fused alumina manufacturing: calcined bauxite, carbon and iron serve as the main material. Materials will be balanced according to the chemical reactions in smelting process, then being put into electric arc furnace and power on. After raw material being smelted, it will restore oxide impurities and extract ferroalloy and corundum meltings. Refining comes after the smelting process, with a purpose to fully restore the oxide impurities by rising the temperature in the furnace, making chemical composition meet the requirements. At the end, cut off the power and cool down the solutions to the room temperature.