Changes in the quality characteristics of typical coking coal during pyrolysis and coking processes

WANG Xu; GAN Xiushi; HOU Shibin; ZHOU Qi; WANG Yan; WU Ji; WANG Chao; ZHU Qingmiao; ZHAO Zhenxing; LIU Fujun; PEI Xianfeng; ZHAO Qi

doi:10.3969/j.issn.1007-7677.2025.01.006

Abstract：Studying the transformation law of the coking coal during pyrolysis and the reflectance and the morphology in coking processes is of great significance for revealing the coking mechanism of coking coal.The differences in vit-rinite reflectance,distribution patterns,and microscopic composition of four types of coking coal were studied using coal petrology analysis methods.The effect of pyrolysis temperature on the flowability of coking coal plastie mass was studied using the gieseler fluidity.The influence of pyrolysis temperature on the surface morphology of pyrolysis solid products was studied using crucible coke experiments and electron microscopy.The results indicate that there are sig-nificant differences in the basic coal quality characteristics of the four types of coking coal,and the correlation be-tween conventional indicators and coke quality is not very significant;JM-4 has the lowest content of vitrinite and it is classified as a low vitrinite coal along with JM-2,JM-1 and JM-3 belong to the mesoscopic coal group;the flow-ability of the corresponding plastie mass in JM-2 and JM-3 increases rapidly with increasing temperature,and the flowability of the plastie mass is basically the same,while the flowability of JM-1 is the smallest at the same tempera-ture;as the pyrolysis temperature increases,the porosity of the pyrolysis products obtained from JM-1 shows a trend of first increasing and then decreasing,with the highest particle porosity corresponding to the maximum flowability of the gel body.