Steel Manufacturing

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nt mass called coke. When coking coal is heated in absence of air, a series of physical and chemical changes take place with the evolution of gases and vapours, and the solid residue left behind is called coke.
Conventional cokemaking is done in a coke oven battery consisting of more than 50 slot ovens, sandwiched between heating walls. Suitable blends of coking coals are crushed to around 80% ( -) 3.2 mm size fraction. They are carbonised at a temperature around 1000-11000 C upto a certain degree of devolatization to produce metallurgical coke of desired mechanical and thermo-chemical properties. A schematic diagram of Coke Oven Battery is given in Fig.below.

Schematic Diagram of Coke Oven Battery
During carbonisation, coking coals undergo transformation into plastic state at around 350-4000 C swell and then resolidify at around 500-5500 C to give semi-coke and then coke. In coke ovens, after coal is charged inside the oven, plastic layers are formed adjacent to the heating walls, and with the progress of time, the plastic layers move ...