EXPERIMENTAL STUDY ON PORE STRUCTURE AND FRACTAL CHARACTERISTICS OF TECTONIC COAL

In order to study the pore structure and fractal characteristics of tectonic coal, high pressure mercury, low temperature liquid nitrogen adsorption and low temperature carbon dioxide adsorption were selected to characterize the pore structure of various tectonic coals, and the fractal model was selected to quantitatively characterize the tectonic coal structure. The results show that the mercury-removing curves of the structural fractured coal are mainly parallel type. The heterogeneity of the adsorption pores in the tectonic coal is gradually enhanced with the increase of structural deformation, and the complex pore structure further increases the complexity of the tectonic coal structure. The tectonic coal Df2 increases with the increase of tectonic deformation, which indicates that the tectonic deformation has a profound influence on the meso-porosity heterogeneity of the tectonic coal, and Df1 gradually increases with the increase of tectonic deformation. The difference between Df1 and Df2 in primary tectonic coal is greater than that of tectonic coal, and the structural deformation reduces the influence of particle size on heterogeneity. The surface and volume heterogeneity of the 0.3 similar to 0.6 nm and 0.6 similar to 1.4 nm sections are significantly different. In general, the surface and volume fractal dimension of the 0.3 similar to 0.6 nm stage are less than 0.6 similar to 1.4 nm.