Comprehensive fractal dimension of coal porosity

• 1、State Key Laboratory Cultivation Base for Gas Geology and Gas Control, Institute of Resources and Environment, Henan Polytechnic University, Jiaozuo, Henan 454000

Abstract：Mercury intrusion porosimetry and nitrogen adsorption experiment were apllied to analyze the pore structure and morphology of the brown, gas, coking and anthracite coal samples respectively collected from the Beozhao, Caiyuan, Xiqu and Guhanshan mines. And the fractal dimensions of coal samples different pore sizes were calculated by the Mercury intrusion porosimetry and Nitrogen adsorption experimental data. The coal fractal dimension results in Mercury intrusion porosimetry show that the brown, gas, coking coal pore fractal characteristics is conspicuous when the aperture is greater than or equal to 10nm and it is less than 100nm about the anthracite coal, while it is not obvious when the aperture is less than 10nm and 100nm. And The coal fractal dimension results in Nitrogen adsorption show that the coal pore fractal characteristics is conspicuous when the aperture is greater than or equal to 2.03nm and less than or equal to361.14nm, but the fractal dimensions of coal samples are different with 10nm and 100nm threshold. On the basis of the above study, the coal porosity comprehensive fractal dimension was defined and calculated. Through this study, the fractal dimensions of the coal pore full aperture have been unified effectively and the coal pore fractal research has been improved. So it is convenient to the characterization of the non-uniformity of coal.

Keywords： coal pore mercury intrusion nitrogen adsorption fractal dimension