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Metals. Metals. 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 ORE is mined from the ground.
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Metals • 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 BLAST FURNACE
Blast Furnace Charge 1. Iron Ore----------------------- 2. Coke------------- (fuel) 3. Limestone-------------------- (Keeps waste bits together)
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 Tuyeres are the nozzles that the hot air is blown through Tuyeres
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 typicallyflows into a channel andindentations in a bed ofsand. • Once it cools, this metal is known aspig 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 degF (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 thingswith 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.