THERMAL SCIENCE

International Scientific Journal

FIELD TEST RESEARCH ON GAS MIGRATION LAW OF MINING COAL AND ROCK

ABSTRACT
The fractures in coal and rock mass are the main channels of gas seepage, and understanding the gas migration law during mining is the precondition of gas control. The long-term in-situ monitoring of the abutment pressure, fracture networks and gas-flow in front of a mining face was carried out and the 1-D connectivity ratio of boreholes were calculated. The results showed that under the influence of mining, the fracture networks developed to the depth of rock stratum, and as far-field gas seepage channels, far-field gas continuously supplied the near-field gas. The gas flow in front of the mining face have undergone two stages of evolution from initial value to peak value, and then to a stable value. The 1-D connectivity ratio the abutment pressure about 5 to 10 m. The 1-D connectivity ratio reflected the dergree of coal and rock fracture penetration caused by mining, and the area with the highest gas extraction efficiency was the transition zone from peak abutment pressure to residual pressure in coal seams.
KEYWORDS
PAPER SUBMITTED: 2018-07-20
PAPER REVISED: 2018-09-13
PAPER ACCEPTED: 2018-12-21
PUBLISHED ONLINE: 2019-05-26
DOI REFERENCE: https://doi.org/10.2298/TSCI180720228P
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2019, VOLUME 23, ISSUE 3, PAGES [1591 - 1597]
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© 2019 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence