Results 1 to 10 of about 92 (71)
Natural Gas Industry B, 2019 Broken coal structure and low permeability are the main reasons for the difficult production of coalbed methane (CBM) in broken-soft coal seams. In this paper, No.8 coal seam in the Luling Mine of the Huaibei Coal Field was taken as an example to study ...
Yaobo Xu, Yushuang Zhu, Peihe Zhang
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Energy Science & Engineering, 2022 Large deformation control of surrounding rock in deep soft‐broken coal roadway has always been a key scientific and technological problem restricting the deep coal resources exploitation.
En Wang, Shengrong Xie
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Fracture propagation and evolution law of indirect fracturing in the roof of broken soft coal seams
International Journal of Coal Science & TechnologyIndirect fracturing in the roof of broken soft coal seams has been demonstrated to be a feasible technology. In this work, the No. 5 coal seam in the Hancheng block was taken as the research object.
Haifeng Zhao +3 more
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Geofluids, 2021 To enhance the coalbed methane (CBM) extraction in broken-soft coal seams, a method of drilling a horizontal well along the roof to hydraulically fracture the coal seam is studied (i.e., HWR-HFC method).
Zhaoying Chen +6 more
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Gong-kuang zidonghua, 2022 The gas extraction method of floor cross-layer drilling commonly used in gas control of broken and soft coal seam has problems such as large excavation quantity, long control period, short coal uncovering section of drilling, limited extraction control ...
SUN Siqing, LI Wenbo
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Meikuang Anquan, 2022 According to the shallow sampling depth, inaccurate measurement and control of sampling position, large gas loss and other disadvantages existed in the available sampling technology for measuring gas content in broken soft coal seam, a sampling ...
CHAI Jianlu
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Meikuang Anquan, 2022 In order to study the effect of particle size and air volume on the deposition, migration and distribution law of pulverized coal in the annulus of drill pipe and hole wall, the Euler-Euler model is used to numerically simulate the gas-solid two-phase ...
NIE Chao, WANG Yi, YAO Yafeng
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Gong-kuang zidonghua, 2023 It is easy to get stuck and collapse in the borehole of high stress and broken soft coal seam in the isolated island working face. This leads to great difficulty in borehole formation and poor gas extraction effect.
CHEN Chao +3 more
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Rockburst mechanism in soft coal seam within deep coal mines
International Journal of Mining Science and Technology, 2017 A number of rockburst accidents occurring in soft coal seams have shown that the rockburst mechanism involved in soft coal seams is significantly different from that involved in hard coal seams.
Junfei Zhang +4 more
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ProcessesAbundant industrial experiences have shown that directional air drilling technology is effective for gas drainage when drilling broken and soft coal seams. In this paper, the Eulerian–Eulerian model was used to simulate the gas–solid two-phase flow behavior of compressed air transporting coal dust in broken soft coal seams. The relationship between the
Xianyu Yang
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