Process of Steel Manufacturing
MANUFACTURE OF STEEL
Three basic raw materials are needed in large quantities for the production of steel
- Iron Ore
- Coal
- Lime stone
The first step in the steel manufacture begins at the blast furnace. To separate iron from iron ore ► coke (substance when gas is taken out of coal), limestone and dolomite are charged into the blast furnace
Temperature raised to 1600oF. This high temp causes the coke to burn and melt the iron. This red hot iron drained at an opening at the base of the furnace. Natural gas is often injected to reduce the amount of coke consumed. The dolomite and limestone combine with the non-ferrous elements of the ore to form a slag, which floats on the top of the molten iron and is removed separately. The product of the blast furnace is known as “Pig Iron” the basic ingredient of steel.
It takes 2 tons of iron ore, 2/3 ton of coke, ½ ton of limestone, 4 tons of air to make 1 ton of Pig iron. Some of the pig iron goes to the foundries to make iron castings, but the vast majority is re melted and used in the production of steel in steel furnace. Several types of furnaces are used for the production of steel including
- Open Hearth Furnace
- Bessemer Furnace
- Electric Furnace
- New Oxygen Furnace