title: Experimental study on properties of methane diffusion of coal block under triaxial compressive stress.
abstract: Taking the standard size coal block samples defined by ISRM as research objects, both properties of methane diffusion of coal block under triaxial compressive stress and characteristic influences caused by methane pressure were systematically studied with thermo-fluid-solid coupling with triaxial servocontrolled seepage equipment of methane-containing coal. The result shows the methane diffusion property of coal block under triaxial compressive stress was shown in four-stage as follow, first is sharply reduce stage, second is hyperbolic reduce stage, third is close to a fixed value stage, fourth stage is 0. There is a special point making the reduced rate of characteristic curve of methane diffusion speed become sharply small; the influences of shape of methane diffusion speed characteristic curve caused by methane pressure are not obvious, which only is shown in numerical size of methane diffusion speed. Test time was extended required by appear of the special point makes the reduce rate of methane diffusion speed become sharply small. The fitting four-phase relation of methane diffusion of coal block under triaxial compressive stress was obtained, and the idea is proposed that influences of the fitting four-phase relation caused by methane pressure were only shown in value of fitting parameters.
authors.affiliation: College of Resources and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China ; State Key Laboratory of Oil and Methane Reservoir Geology and Exploitation (Southwest Petroleum University), Chengdu 610500, China ; State Key Laboratory of Coal Resources and Safe Mining, China University of Mining & Technology, Beijing 100083, China.
authors.forename: Hong-Bao
authors.initials: HB
authors.lastname: Zhao
mesh_terms: D003031:Coal; D019245:Compressive Strength; D004058:Diffusion; D008697:Methane / Q000032:analysis*; D011312:Pressure; D013314:Stress, Mechanical
chemical_list: D003031:Coal; D008697:Methane