Mineev S.P., Prusova А.А., Mineev О.S. Simulation of desorption of methane adsorbed in the coal seam with considering intermolecular sorption interactions in the system

Details
Parent Category: Geo-Technical Mechanics, 2018
Category: Collection of scientific papers «Geotekhnicheskaya Mekhanika» Issue 141

Geoteh. meh. 2018, 141, 99-106

https://doi.org/10.15407/geotm2018.141.099

SIMULATION OF DESORPTION OF METHANE ADSORBED IN THE COAL SEAM WITH CONSIDERING OF INTERMOLECULAR SORPTION INTERACTIONS IN THE SYSTEM

1Mineev S.P., 1PrusovaА.А., 2MineevО.S.

1Institute of Geotechnical Mechanics named by N. Polyakov of National Academy of Sciences of Ukraine, 2National Technical Univercity «Dnipro Polytechnic»

UDC 622.831: 642.411

Language: Russian

Annotation.

Presently development and introduction in industry of high-effectively technologies of of coal and gas mining is related to the necessity of account of the methane related to the coal by sorbtioning communication. Having analyzed the stages of desorption of methane adsorbed in the coal seam, this process was simulated basing on its consideration as an activation process of diffusion. It was found that intermolecular sorption interactions in the «methane-coal» system should be described by the Lennard-Jones potential and with taking into account polymeric nature of the coal molecular structure. Because of this, modern theories on kinetics of nonequilibrium sorption processes in high-molecular materials were analyzed. This analysis shows that it is most correctly to take into account a complex of the main molecular factors in the system “methane–coal” by using the Pace–Deutiner molecular parameters, while diffusion coefficient takes into account activation energy of the diffusion process, intermolecular sorption interactions in the «methane-coal» system, parameters of the microstructure of coal, physical properties of methane and magnitude of its diffusion jump. Boundary conditions were determined for the diffusion equation and its analytical calculation of was performed, which allowed determining the patterns of desorption process in various geological conditions of mining operations. The developed model of the methane desorption process in a coal seam is represented by a diffusion equation with a diffusion coefficient that takes into account the diffusion activation energy, as well as a set of structural parameters of the molecular structure of coal, and the physical properties of methane allows us to determine the magnitude of its diffusion jump in a given molecular structure. The analytical expression obtained during modeling for calculating the laws of the desorption process has an exponential form. Given the boundary conditions obtained for the coal mass, this equation allows us to establish the desorption patterns of methane in various mining and geological conditions of coal mining operations.

Keywords: modeling, coal – methane, sorption, diffusion, properties.

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About the authors

MineevSergeyPavlovich, Doctor of Technical Sciences (D.Sc.), Professor, Head of the Department of Pressure Dynamics Control in Rocks of the Institute of Geotechnical Mechanics by N. Polyakov of National Academy of Sciences of Ukraine (IGTM NASU), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. ,

Prusova Alla Andreevna, Candidate of Technical Sciences (Ph.D.), Senior Researcher in the Department of Pressure Dynamics Control in Rocks of the Institute of Geotechnical Mechanics by N. Polyakov of National Academy of Sciences of Ukraine (IGTM NASU), Dnipro, Ukraine

Mineev Aleksandr Sergeevich, Candidate of Technical Sciences (Ph.D.), Associate Professor of the National Technical University "Dnipro Polytechnic", Dnipro, Ukraine