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

Study on the plasticity of coals mixed with asphalts and pitchesby

Abstract

As for a study on the coking property of asphalst and pitches, the plasticity of coals mixed with those additives was pursued. Three kinds of the blended coals were prepared as base coals for mixing with additives. When these base coals were carbonized without the additives, they were lacking in coke strength compared with the blast furnace cokes. The plasticity was measured with a Gieseler plastometer and with a Audibert-Arnu dilatometer.
Addition of asphalts or pitches to the base coals gives the following results.
1) Initial softening temperature and initial dilating temperature shifted to lower range, but solidification temperature was almost unchanged.
2) Maximum fluidity was increased with amount of additives.
3) The limits of softening temperature and dilating temperature were broadening to lower range.
4) Increase of maximum fluidity was not always connected with a big increase of dilatation.
5) Fluidity and dilatation characteristics closely depended on those of base coals themselves, so, effects of additives on the plasticity were fairly limited by quality of base coals.