Investigation of bonding mechanism of coal particles and gengrating mechanism of coke strength during carbonization.

Abstract

The coking is not a single process, but consists of two mechanisms, that is, a bonding of coal particles and a generation of coke strength. From this point of view, both processes have been investigated and the following model is proposed.(1) A bonding of coal particles, which can be considered as foamable particles, is determined by a mechanism that the voids between particles are filled up by the dilatation of coal. An insufficient bonding between particles yields a structural defect, and is a primary factor in lowering coke strength.(2) The generation of coke strength determines both the porosity and inherent strength. Thermally decomposed gas and melting materials during the carbonization process influence the porosity. As for inherent strength, it is clear that influences of a coalification rank and carbonization temperature are significant.Based on these results, a concept of the coking mechanism across the oven width, which is the basis of the reaction in the coke oven, has been considered.