Methane migration and explosive fringe localisation in retreating longwall panel under varied ventilation scenarios: a numerical simulation approach

Rao, Sunny; Mishra, Devi Prasad; Mishra, Aishwarya

doi:10.1007/s11356-023-26959-6

Cited by 6 publications

(1 citation statement)

References 36 publications

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“…The air intake of the working face provides the driving force for gas migration in the mining space and has a significant influence on the emission of low-oxygen gases in the top coal caving working face of ultrathick coal seams. , Therefore, it is necessary to conduct a systematic study on the influence of a single factor of air intake volume on the oxygen concentration of the mining space. In this study, the parameters of nitrogen injection remain unchanged.…”

Section: Resultsmentioning

confidence: 99%

Research on the Low-Temperature Oxygen Consumption and Low-Oxygen Gas Emission Law in Goaf of Ultrathick Coal Seams

Zheng,

Liu,

Liu

et al. 2024

ACS Omega

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Low-oxygen (oxygen concentration below 18.5%) phenomena often occur in the top coal caving working face of ultrathick coal seams, posing a serious threat to the safety of workers. The characteristics of oxygen consumption and gas production at low-constant temperature and the corresponding functional group evolution of residual coal in goaf were studied by temperatureprogrammed and infrared spectrum experiments. The influence of different factors on the emission of low-oxygen gases was studied through numerical calculation. The results show that low-temperature oxygen consumption and gas production occurred when the coal was about 40 °C. When the temperature was constant, the oxygen consumption and gas production rate increased with the extension of time. In the early stage of coal oxidation, the aliphatic C−H components were attacked by oxygen molecules and reacted with them. The asymmetric methyl and methylene groups were more likely to oxidize and produce carbonyl compounds. With the increase of nitrogen injection, the overall width of the oxidation zone (oxygen concentration was defined as 10−18%) narrowed, and the range of the oxidation zone moved forward from the depth of the goaf. The oxygen concentration in the air return corner decreased gradually, and the low-oxygen area in the air return corner expanded gradually. The distance between the lowoxygen area of the working face and the air intake corner was gradually shortened. With the increase of air intake, the width of the oxidation zone increased and moved to the depth of goaf, and the degree of low oxygen in the air return corner increased. The research results are of great significance for the understanding and prevention of the low-oxygen phenomenon in ultrathick coal seams.

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Section: Resultsmentioning

confidence: 99%

Research on the Low-Temperature Oxygen Consumption and Low-Oxygen Gas Emission Law in Goaf of Ultrathick Coal Seams

Zheng,

Liu,

Liu

et al. 2024

ACS Omega

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Research on gas hazard prevention and control of a high-gas fully mechanized mining face based on ventilation system optimization

Xie,

Chen,

et al. 2023

Environ Sci Pollut Res

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Numerical analysis of the possibility of noxious gases infiltration into a shelter located in a gas-bearing coal-rock mass

Krukovska,

Krukovskyi,

Demchenko

2023

Geoteh. meh.

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Shelters in coal mines are used to protect miners during accidents associated with gassing of roadways, fires, explosions of methane-air mixture. Supporting of the shelter must provide the necessary level of tightness to prevent the penetration of noxious gases from the mine atmosphere or gas-bearing rocks. The purpose of this work is to study the possibility of noxious gases penetration into a shelter in case of its sealing failure for the early detection of weak constructional elements and to ensure safe conditions for people in the shelter during accidents. To achieve the goal, methods of numerical simulation of time-dependent processes of elastic-plastic deformation and gas filtration were used. A coal-rock mass with a roadway and an adjacent shelter with typical supporting elements were considered at a depth of 400 m and 1000 m. The study of the stress state of the shelter support showed that under the considered conditions, in the case of a relatively small depth, hard steel and concrete constructional elements withstand the load without loss of their stability. With an increase in the depth of the shelter location, inelastic deformation of the concrete barrier between the shelter and the roadway occurs on a small area. The probable destruction of this zone will not lead to a violation of the entire barrier integrity, which makes it impossible to start mass exchange processes between clean air in the shelter and harmful combustion products in the roadway. The roof and walls of the shelter, covered with reinforced concrete and sealed, remain practically impermeable from the next day after their construction in both the first and second cases. But later, in the lower left corner of the shelter at a depth of 1000 m, methane from the coal seam begins infiltrating through the unsupported and unsealed floor. The developed numerical model can be used with other basic data on mining and geological conditions to identify constructional elements of a shelter, which lose stability during operation and threaten the shelter's tightness. Timely strengthening of such weak elements will prevent the danger of noxious gases infiltrating into the shelter. Keywords: time-dependent rock deformation, shelter, sealing failure, gas filtration, numerical simulation.

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Methane migration and explosive fringe localisation in retreating longwall panel under varied ventilation scenarios: a numerical simulation approach

Cited by 6 publications

References 36 publications

Research on the Low-Temperature Oxygen Consumption and Low-Oxygen Gas Emission Law in Goaf of Ultrathick Coal Seams

Research on the Low-Temperature Oxygen Consumption and Low-Oxygen Gas Emission Law in Goaf of Ultrathick Coal Seams

Research on gas hazard prevention and control of a high-gas fully mechanized mining face based on ventilation system optimization

Numerical analysis of the possibility of noxious gases infiltration into a shelter located in a gas-bearing coal-rock mass

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