About degassing of coal-rocks massif in the roof of coal seam being worked out

The article is devoted to the consideration of various aspects of methane mass transfer in a coal-rock massif and the possibility of using extended horizontal bore-hols in the roof of a coal seam for its degassing. Considerable attention is paid to the analysis of changes in the stress-strain state of roof rocks as the developed space develops. It is shown that during the development of the seam by long extraction columns with a longwall length of several hundred meters, almost all mining occurs in the mode with a complete roof landing in the central part of the column. As to a greater length of the rest part, a partial landing occurs, and only near the faces and side boundaries of the column, zones of a hanging roof are formed. In accordance with the nature of the interaction between the rocks of the roof and the bottom, areas of relief from vertical compressive stresses are formed in the massif. Significant permeability is created in these zones, providing intensive methane filtration. Wherein, the location of the degassing well relative to the roof of the formation significantly determines the efficiency of methane removal from the array. At the same time, largely, the methane output is determined by the size of the discharge zone in the roof of the formation and the exit through the roof into the developed space, even in the presence of several degassing boreholes.

Keywords: methane, coal-rock massif, filtration, stress-strain state, permeability, degassing boreholes, unloading, numerical modeling.
For citation:

Zakharov V. N., Trofimov V. A., Filippov Yu. A., Shlyapin A. V. About degassing of the coal-rocks massif in the roof of the coal seam being worked out. MIAB. Mining Inf. Anal. Bull. 2022;(11):20-36. [In Russ]. DOI: 10.25018/0236_1493_2022_11_0_20.

Acknowledgements:

The study was supported by the Ministry of Science and Higher Education of the Russian Federation, Agreement No. 075-15-2021-943 and the European Commission Research Fund for Coal and Steel (RFCS) funded project «Advanced methane drainage strategy employing underground directional drilling technology for major risk prevention and greenhouse gases emission mitigation» GA: 847338-DD-MET-RFCS-2018/RFCS-2018.

Issue number: 11
Year: 2022
Page number: 20-36
ISBN: 0236-1493
UDK: 622.81
DOI: 10.25018/0236_1493_2022_11_0_20
Article receipt date: 14.09.2022
Date of review receipt: 03.10.2022
Date of the editorial board′s decision on the article′s publishing: 10.10.2022
About authors:

V.N. Zakharov1, Аcademician of Russian Academy of Sciences, Director, e-mail: ipkon-dir@ipkonran.ru, ORCID ID: 0000-0002-9309-2391,
V.A. Trofimov1, Dr. Sci. (Eng.), Head of Laboratory, e-mail: asas_2001@mail.ru, ORCID ID: 0000-0001-9010-189X,
Yu.A. Filippov1, Cand. Sci. (Eng.), Senior Researcher, e-mail: filippov.yury@gmail.com, ORCID ID: 0000-0003-3347-677X,
A.V. Shlyapin1, Cand. Sci. (Eng.), Deputy Director for Science, e-mail: Shlyapin@mail.ru, ORCID ID: 0000-0002-9442-0983,
1 Institute of Problems of Comprehensive Exploitation of Mineral Resources of Russian Academy of Sciences, 111020, Moscow, Russia.

 

For contacts:

A.V. Shlyapin, e-mail: Shlyapin@mail.ru.

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