The first step in manufacturing of aluminum is mining raw material
even though aluminum is the most common metal on the planet
pure aluminium does not occur naturally
there are several minerals available in the world from which aluminum can be obtained
like cryolite feldspur corundum etc
but the world's primary source of raw material for making aluminium is bauxite
and now step 2 extracting alumina from raw material bauxite
first the bauxite ore is mechanically crushed
then the crushed ore is mixed with caustic soda
and processed in a grinding mill to produce a slurry
then the slurry is pumped into a digester
in the digester the slurry is heated to 270 degrees celsius under pressure
the caustic soda reacts with the aluminium compounds in bauxite material
to produce a solution of sodium aluminate
then it is pumped into a settling tank as the slurry rests in the tank
impurities that does not dissolve in the caustic soda settle to the bottom of the vessel
after the impurities have settled out
the remaining liquid is pumped through a series of cloth filters
any fine particles of impurities that remain in the solution
are trapped by filters now the sodium aluminate solution
is pumped into a large precipitators
aluminum hydroxide seed crystals are added to the solution
to start the precipitation process at this point large aluminum crystals are formed
the crystals are then heated in rotary kilns to temperatures over 960 to 1100 degree celsius
this dries off the water molecules leaving a white powder known as alumina or aluminium oxide
now step 3 smelting alumina into metallic aluminum
aluminum smelting requires large amount of electricity and it takes place in a steel vat called reduction pot
the bottom of the pot is lined with carbon which acts as one electrode usually cathode
the opposite electrode which is anode consists of a set of carbon rods
suspended over the pot and an alumina feeder which releases alumina periodically into the pot
within the reduction pot alumina crystals are dissolved in molten cryolite at temperatures
of 960 to 970 degrees celsius to form an electrolyte solution
that will conduct electricity from the carbon rods to the carbon land bed of the pot
the resulting reaction breaks the bonds between aluminum and oxygen atoms in the alumina molecules
the oxygen that released is attracted to the carbon rods where it forms carbon dioxide
the freed aluminum atoms settle to the bottom of the pot as molten metal
a crucible is moved down to the potline and collects molten aluminium
the pure molten aluminium collected in crucible is transferred to a holding furnace
and then cast as ingots using saw casting open mould casting sheet casting or billet casting etc
and these are some of the basic steps involved in manufacturing of aluminium
Haz clic en cualquier texto o marca de tiempo para ir directamente a ese momento del video
Compartir:
La mayoría de las transcripciones están listas en menos de 5 segundos
Copia con un clicMás de 125 idiomasBuscar en el contenidoIr a marcas de tiempo
Pega la URL de YouTube
Ingresa el enlace de cualquier video de YouTube para obtener la transcripción completa
Formulario de extracción de transcripción
La mayoría de las transcripciones están listas en menos de 5 segundos
Instala nuestra extensión para Chrome
Obtén transcripciones al instante sin salir de YouTube. Instala nuestra extensión de Chrome y accede con un clic a la transcripción de cualquier video directamente desde la página de reproducción.
Extensión Chrome