关键词: 岩浆侵入, 煤的吸附特性, 镜质组反射率, BET比表面积, 微孔孔容

Abstract: In this paper，to study the effect of igneous intrusion on adsorption characteristics of coal to gas，taking 11 samples of No.10 coal seam in Wolonghu coalfield as research object，we compares and analyzes the relationship between the multivariate physical properties of coals and the distances from coal samples to igneous rocks，by synthetically using the methods of industrial analysis，CH4 isothermal adsorption experiments，BET surface area calculated by liquid nitrogen adsorption method，and micro-pores measured by CO2 adsorption method．The results show that the thermal evolution area of magmatic is about 60 m．When approaching the igneous rocks，the vitrinite reflectance (Rm) increases from 2.74% to 5.03%，the volatile matter decreases from 16.04% to 6.85%，and the metamorphic grade of coal increases．Meanwhile，the adsorption constant (a) increases first and then decreases，while the maximal adsorption constant (No.8 coal sample in thermal evolution area) is 59.02 m3/t，and the minimal value (No.1 sample in magmatic covering area) is 13.53 m3/t．In addition，there is good relativity among the distribution curves of adsorption constant，BET surface area，and micro-pore volume．Furthermore，the numerical values in thermal evolution area are higher than that in normal area，while the values in normal area are higher than that in magmatic covering area．Moreover，the  adsorption ability of coal to gas is reduced because of the contact metamorphism of magmatic，however，duo to the igneous intrusion，the micro-pores of coal samples in thermal evolution area are more development，BET surface area is more larger，gas adsorption positions increase，and the adsorption ability of coal to gas is enhanced．

Key words: igneous intrusion, adsorption characteristics of coal, vitrinite reflectance, BET surface area, micro-pore volume