Metallurgical coal
Coke Production Process
Coking coal – coal suitable for making into coke. Coke is produced from carefully selected grades of coal. Different grades of coal are stocked separately and blended before transfer to coke ovens. The coal is heated, or ‘carbonized’ in the ovens until it becomes coke. It is then removed from the oven, cooled and graded before use in the blast furnace.
Coke is used chiefly to smelt iron ore and other iron bearing materials in blast furnaces to produce pig iron, or hot metal.
Coke, iron ore, and limestone are fed into the blast furnace, which runs continuously. Hot air blown into the furnace burns the coke, which serves as a source of heat and as an oxygen reducing agent to produce metallic iron. Limestone acts as a flux and also combines with impurities to form slag.
The basic raw material for steel manufacture is either the hot metal from the blast furnace, steel scrap or a mixture of both. The proportions of material used vary according to the process and the type of steel required. Steel can be described in general terms as iron with most of the carbon removed, to make it tougher and more ductile. There are many forms or ‘grades’ of steel, each with its own specific chemical composition and properties to meet the needs of the many different applications.
