Have you ever wondered how aluminium is made? скачать в хорошем качестве

Have you ever wondered how aluminium is made?

Aluminium is at the heart of modern life, from the smartphone in your hand, to the plane you fly in, to the buildings where you live and work. As economies grow and living standards rise, industry experts expect that demand for aluminium will increase. Learn more about Aluminium: https://www.ega.ae/en/products/ Step 1: Bauxite Mining The production process for aluminium starts with the mining of bauxite ore. Layers of bauxite are generally found near the surface so it is extracted through open cast mining. Around 90% of the world's resources are in tropical & sub-tropical regions Step 2: Alumina Refining Bauxite is refined into alumina using the Bayer process. Two or three tonnes of bauxite are required to produice one tonne of alumina. In the digestion stage, hot caustic acid is added to the bauxite to dissolve the aluminium bearing minerals in the bauxite. Clarification separates bauxite solids from the pregnant liquor via sedimentation. In the precipitation stage, alumina crystals are recovered from the liquor via crystallization. Calcination is a roasting process to remove the remaining water. Step 3: Aluminium Smelting Alumina is smelted into aluminum using the Hall-Heroult process. It takes two tonnes of alumina to produce one tonne of aluminium. Alumina is poured into special reduction cells called pots with an electrolytic bath of molten salt called cryolite at temperatures around 960 degrees Celsius. An electrical current is then projected into the mixture at 400KA or above. This current then breaks the bonds between aluminium and oxygen atoms in alumina, resulting in liquid aluminum settling at the bottom of the reduction cell. Step 4: Casting Aluminium is then transferred to the cast house, where it is made into products using several different methods. Alloys are added into many of our products, according to customer specifications, before the solidification stage. In re-melt casting aluminum, at a temperature of 700 degree Celsius, is poured into moulds. The moulds are cooled and the aluminium solidified before being packed and shipped to the customer. EGA also supplies nearby customers in Khalifa Industrial Zone Abu Dhabi. Receiving aluminum as molten metal eliminates the need to use high energy to re-melt it before use. We transfer molten metal by truck in preheated 14.5 tonne crucibles which can keep the metal liquid for 18 hours at temperatures of around 780 degrees Celsius.