Tula State University, Tula, Russia:

N. M. Kachurin, Doctor of Engineering Sciences, Professor, Head of a Chair, ecology@tsu.tula.ru

Belgorod State University, Belgorod, Russia:

S. A. Vorobev, Researcher, office@rudmet.ru

”Siberian Expert Organization” Company, Russia, Prokopevsk (Kemerovo Region):

P. V. Vasilev, Сandidate of Engineering Sciences, Chief Executive Officer, Sib_EO@bk.ru

Exploitation practice of Russian coal mines in whole and Kuznetsk Basin especially shows that safety level of underground mining by gas factor is constantly reduced. The reason of this situation is conversion to intensive mining technologies, when production can be more than 20000 ton per day and mining depth is constantly increasing. American scientists noted that coal mine methane, emitting into mining atmosphere from mined beds and enclosing strata, is a major problem of coal industry. Intensity of gas emission depends on coal gas content, mining productivity, geological conditions and technological parameters. A part of coal methane is removed by degassing system and this part of gas can be used as energy carrier. But another part can be the reason of accident, therefore mining ventilation systems have to solve the problem of creating safety mining atmosphere. Thus researching methane emission processes and their modeling from different sources are very important topical modern problems. Generalized mathematical model of filtrating gases in coal beds and rocks is based on hyperbolic-type equation and using parabolic equation is physically substantiated for large time periods. Resistance law by gas filtration moving in massif is functional connection of gas flow with gas pressure gradient and local velocity of changing gas flow. Gas permeability of mining massif is generalized characteristic of gas properties, collecting properties of porous medium and relaxation process of gas filtration moving. Numerical value of gas permeability is proportional by third power of mining massif effective porosity. Relaxation period at resistance law characterizes stochastic property of filtration moving in porous medium and one is numerical equal to correlation scale of moving gas process in mining massif.

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