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There are two groups of Metals

Ferrous – consist mainly of IRON

Non Ferrous – contain NO IRON


Where do metals come from?

Metals come from rocks
in the ground called ORE

The metal must then be taken from the Ore and a big Furnace does this.

Iron

Iron comes from Iron Ore which is excavated from the ground.

The furnace used to separate the Iron from the rocks is called a





Iron Ore


Iron ore is a rock that contains iron combined with oxygen.

Some of the world's highest quality iron ore comes from Australia.



Coke
Coke is made from coal. Once mined, the coal is crushed and washed.

Coal is then baked in coke ovens for about 18 hours.

During this process, by-products are removed and coke is produced.
Flux
Flux is a term for minerals used to collect impurities during iron and steelmaking.

Limestone and dolomite are fluxes.

The flux causes a chemical reaction and elements not needed for steelmaking join together to form slag.
Blast Furnace
Blast Furnace operation

The Charge is fed in at the top,


Bell Doors open (One at a time)


Coke burns & makes Carbon Monoxide,


The Carbon Monoxide mixes with the Oxygen in the Iron Ore (leaving Iron),
Blast Furnace
The Molten Iron falls to the bottom of the Furnace,

The limestone joins with the impurities to make Slag and floats on top of the Molten Iron.
Blast Furnace
The slag and the Molten Iron are tapped off regularly,

Blast Furnace Waste
Slag, Ammonia, Light Oils and Coal Tars are waste from the Furnace,

They make raw
materials for cements,
plastics and fertilisers.
Blast Furnace Iron
Special rail cars bring the Molten Iron away,
The liquid iron typically flows into a channel and indentations in a bed of sand.
Once it cools, this metal is known as pig iron.
Why is Pig Iron called Pig Iron ?
PIG IRON is raw iron in an ingot form.

It is the result of smelting Iron Ore, Coke and Limestone in a blast furnace.

It is a hard but brittle mix of iron (90% or more) and carbon (typically 4-5%), manganese, sulfur, phosphorus, and silicon (roughly 3% in total).

The name is derived from the time when the iron ran into moulds. A row of moulds was said to resemble a litter of suckling pigs, so the single ingots were referred to as pigs.

To create a ton of pig Iron
We start with 2 tons of ore,
1 ton of coke and
½ ton of limestone.
The fire consumes 5 tons of air.
The temperature reaches almost 3000 deg F (about 1600 degrees C) at the core of the blast furnace!

Pig iron contains 4 percent to 5 percent carbon and is so hard and brittle that it is almost useless. We do one of two things with pig iron:
You melt it, mix it with slag and hammer it to eliminate most of the carbon (down to 0.3 percent) and create wrought iron.
Wrought Iron
Wrought iron is the stuff a blacksmith works with to create tools, horseshoes and so on. When you heat wrought iron, it is malleable, bendable, weldable and very easy to work with.

Or we can create steel.

Steel
Steel is iron that has most of the impurities removed.
Steel also has a consistent concentration of carbon throughout (0.5 percent to 1.5 percent).
Impurities like silica, phosphorous and sulfur weaken steel tremendously, so they must be eliminated.
The advantage of steel over iron is greatly improved strength.
Blast Furnace Iron
The Iron must go into a second furnace to make it into a better quality metal (Steel)

At the Steel making factory, it is mixed with recycled steel and other alloys to make new steel

Iron into Steel
The Iron that comes from the Blast Furnace requires further treatment to produce Steel,

This is done in:
1. The Bessemer Converter or
2. The Basic Oxygen furnace.