A Study on the Coking Property of Asphalts and Pitches (III)

Abstract

As for a study on the coking property of asphalts and pitches, the influence of those additives on the strength of the coke was pursued. Firstly, the caking index, which was measured by means of carbonizing the coke powder mixed with additives, was obtained. Then, two kind of base coals mixed with additives were carbonized using the method of L. C. T.(Laboratory Coking Test).The following results were presented.1) The additives affected the nature of the plastication of base coals such as extending a plastic temperature range, increasing a maximum fluidity and forming the high-molecular thermally stable substances.2) The additives also increased the caking capacity as a result of the accumulation of the liquid phase in the plastic mass.3) Asphalts, particularly increasing a maximum fluidity and probably promoting the formation of high-molecular thermally stable substances, created conditions for better caking of the coals and hence for the production of stronger coke.4) Pitches enriched with highly condensed aromatic hydrocarbons should be used as additives to the poorly caking coal of high coalification for improving the quality of the coke.5) The caking capacity of additives did not always depend on the degree of aromatic condensation. Effects of additives on the strength of the coke were limited by quality of base coals.