Study on Microstructure of Raw Coal Pyrolysis Coke

The objective of this study is to examine the alterations in the micro-optical properties of blast furnace fuel following combustion, and to establish a theoretical framework for the selection of injection fuel in industrial blast furnaces. This research examines the average reflectivity and optical structure of different types of coal (lignite 1#, bituminous coal 2# and 3#, and anthracite 4#) at various coking temperatures (ranging from 500 to 1000°C) using a digital coal and rock analyzer. The findings indicated that the optical microstructure of samples 1# and 4# consistently exhibited a predominant component, whereas samples 2# and 3# displayed a significant presence of anisotropic microstructure throughout the pyrolysis process. As the pyrolysis temperature rises, the anisotropic structure of coke derived from 2# and 3# coals also increases. Additionally, the mean reflectivity of coke derived from the four types of coals increases as the coalification degree increases at the same temperature.