Gorbachev Kuzbass State Technical University, Kemerovo, Russia:

V. V. Dyrdin, Professor, Doctor of Engineering Sciences
S. A. Shepeleva, Associate Professor, Candidate of Engineering Sciences, shepelevasa@kuzstu.ru
Yu. I. Polygalov, Professor, Doctor of Physical and Mathematical Sciences

The article examines the probable causes and mechanism of gas disbalance in case of coal and gas outbursts. Coal is a complex organic compound. The properties of the outburst-hazardous coal seams in Kuzbass are analyzed. Various forms of methane–coal matrix coupling are considered. The model of distribution of methane molecules in the pore space of coals is proposed. According to various studies, the micropore volume can be up to 89 % of the total pore volume. The authors calculated the magnitude of the forces of interaction between methane molecules in the first and subsequent layers in the pore space with the surface of coal matter, as well as the magnitude of the
forces acting on methane molecules during vacuum degassing of coal seams. It is shown that removal of methane molecules of the first layer located near the surface of coal is impossible in this way. The estimate of the volume of methane, molecules of which are in the pores of coking coal on the surface of the coal substance, is given. Taking into account the percentage distribution of pores, micropores may contain 166.3–242.7 m³/ton of methane, which can only release when the microporous structure is destroyed. The calculation results were compared with the volume of the emitted gas–air mixture during an outburst in Chertinskaya-Koksovaya mine in Kuzbass, and the discrepancy was 7.4%. The proposed method of estimating the volume of methane in the pore structure of coal increases the accuracy of determining the natural gas content of coal seams.

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