Bauxite mining, the aluminium production starts with the mining of bauxites, an aluminum rich mineral in the form of aluminium hydroxide. About 99% of global bauxite supply is found in tropical areas.
The name “Bauxite” comes from “Baux-de-Provence”, the French village where the mineral was first discovered in 1821.
Crushing, digestion, precipitation
Pure aluminium oxide, called alumina, is extracted from bauxite via a process called refining. Bauxite is crushed, dried and ground in special mills where there is mixed with a small amount of water. This process produces a thick paste that is collected in special containers and heated with steam to remove most of silicon present in bauxites.
Both the aluminium hydroxide and the aluminium oxide have further applications outside of the metal industry.
Electrolytic reduction
Reduction process
At aluminum smelter, alumina is poured into special reduction cells with molten cryolite at 950℃. Electric currents are then induced in the mixture at 400Ka or above, this current breaks the bond between the aluminium and oxygen atoms resulting in liquid aluminium settling at the bottom of the reduction cell.
Casting primary aluminum
Once the liquid metal is collected it is transferred in the cast house, where it is purified, alloyed to specification and then cast into ingots and shipped to customers. Or used in the production of aluminium alloys for various purposes.
A luminium alloys
The process where the alimunium is shaped to its required form. This process is used for making the vast majority of aluminium products for window frame, laptop bodies, engine, or solar mounting structures.
Foundry alloys Rolling Extrusion
Recycling
Aluminium is corrosion resistant so it can be remelted and resued an infinite number of times. The added benefit is that recycling aluminium requires only 5% of the energy needed to make the same amount of primary aluminium.
1 billion tonnes of aluminium have been produced since 1886 and ¾ of that metal is still in use today.
Properties of aluminium
What is aluminum?
Aluminium ground mounting
Ground Mounting System
