Structural Comparison of Metallurgical Coke and Coke Used in Electric ...
On heating in the absence of air, the coking coal is converted to a plastic liquid state. The plastic mass surrounds solid grains of noncoking coal. This is a cementation process. Accordingly, coke of sufficient strength may only be obtained from clinkering coal. On heating the coal grains to 455°C, most of the plastic material decomposes.