The dependence of physical structure of a coal heated in a coking chamber on non-uniform distribution of a temperature

Temperature conditions in a coal charge during coking depend on the location towards heating walls of a coke oven. Heating rate as well as residence time in a final temperature distinctly increases from a central axis to heating walls of coking chamber. Differentiated temperature conditions affect physical structure of a coal heated. This influence has been studied using molecular acoustics and densitometric methods, EPR spectroscopy and optical microscopy. Distinct correlations between the position of the coal charge in coking chamber and physical properties of resultant coke have been found. Three zones with the coke of various physical structures have been distinguished in relation to their position toward heating walls of coking chamber: zone I — close to the heating wall, zone II — the middle area and zone III — close to the central axis. Coke produced close to the heating walls of the coke oven has better ordered texture of carbon matrix but more free radicals and worse elasticity than the coke from the middle area. Coke obtained in the central part of coking chamber has the lowest degree of textural order, the lowest porosity but, in a consequence, the best elasticity.The best quality seems to have the coke from the middle area.