The blast furnace

 

In order to extract the iron, sinter, pellets, ore, and coke are fed into the blast furnace.

The iron oxides are converted into metal through teh coke combustion. 

Hot air is blown through nozzles to generate the heat that is necessary for smelting the metal and slag. 

The separated iron is transformed into cast iron towards 1475°C.

The slag which is lighter floats on top of the hot metal and can be easily removed.  

Adjusting the slag basicity ratio is done mainly by adding limestone.