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STEEL MAKING PROCESS
Steelmaking is the process for producing steel from iron ore and scrap.
What it is the Steel making process?
First stagePreparing the mineral of iron
It starts in the mine or quarry, where it´s obtained. In nature is a rock whith iron, oxide, dirt and other impurities.
The first process:
The impurities are removed in the first part of the process, when de gangue is separated from the ore.
The second process of preparing the mineral of iron is:
• The mineral is washed to remove dirt.• It´s crushed into sand.•The sand is sieved, and then, again separated from the ore.
Second stageThe blast furnace
Lime stone, coke and ore are introduced.
• Coke: is a fuel whith few impurities and high carbon content, usually made from coal.
• Limestone: a sedimentary rock consting predominatly of calcium carbonate.
• Ore: the usable part of the rock of iron.
The hot is injected from nozzles at the bottom of the furnace,this way, the reaction is acelerated and the temperature rises higher.
The temperature is very high, over 1500ºC
The lower part of the blast furnace is called crucible.Melted minerals precipitate on it. Pig iron acomulates at the botton and the slag stays aboveit. They are separated, the pig iron is the usable part.
The pig iron usually cool in molds, after, they are transported tosteel companies.
PROBLEM:The pig iron contents too much carbon and impurities in thecomposition. Needs to reduce it before becoming steel.
Third stage
The carbon and other impuritiees are reduce inside the converter.
Scrap is added to the pig iron, so the scrap is recicled.Oxygen is injected in order to burn the carbón and eliminate the impurities.After, slag is remove. And the liquid Steel is ready to get the final shape.