Abstract
In order to evaluate coal for metallugical coke, thermogravimetric analysis, quantification of gaseous products during pyrolysis, caking and coking properties of different rank of coals including air oxidized were investigated. Following results were obtained.
(1) Degree of oxidation of coals can be detected by monitoring the change of CO, CO2 and CH4 in pyrolytic gases.
(2) The higher was the CH4 concentration in the gases, the higher was the resolidified temperature with Gieseler plastometry become. The developement of the optical anisotropy in coke texture was implicated with CH4 evolution.
(3) Coals with the large extent of thermal weight loss and the higher ratio of CH4 in pyrolytic gases showed generally excellent plasticity, although the coal gave cokes with higher porosity.
Coking properties of coals were discussed from the view of the structural aspect. The quantification of thermal weight loss and the concentration of CH4 in pyrolytic gases were introduced as the criteria of coking characteristics.
