Page 31 - Curriculum Visions Dynamic Book

The steel furnace
Just as the iron-making process is chemistry on a grand scale, so too is the steelmaking process.
The steel furnace is where the charge of scrap steel and iron is heated, and where the chemical reactions occur. The first steel furnace was the Bessemer converter, invented by Henry Bessemer in the 1850s. It uses a large pot lined with a basic material such as limestone (calcium carbonate). A blast of air is introduced into the molten iron, causing the iron to oxidise and release a large amount of heat.
As the temperature in the steel furnace rises, the limestone decomposes, releasing calcium oxide. The impurities in the iron react with the calcium oxides to form a molten slag. At this stage the furnace “blows”: huge flames appear at the furnace mouth and gases boil up through the liquid metal.
oxidation: a reaction in which the oxidising agent removes electrons.
The oxygen from
the iron combines with excess carbon in the iron, oxidising it to carbon monoxide. In this way the high carbon content of the iron is lowered, and impurities left in the iron from the blast furnace stage are removed.
The Bessemer converter has been improved and
is now called the basic oxygen furnace process. However, the chemical reactions that take place remain the same.
 This engraving shows a Bessemer converter in use in the last century.
 An integrated iron and steel works, such as this one in Port Kembla, New South Wales, can be regarded as a giant chemical works.
 Sir Henry Bessemer.
 Inside a steel-rolling mill.
Steel furnace
Blast furnace
Raw materials on the dock side
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