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Physical Sciences and Mathematics Commons

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Earth Sciences

2022

Coal Geology & Exploration

Hydraulic fracturing

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Experimental Study On The Mechanical Properties Of Coal-Like Materials For Hydraulic Fracturing Simulation, Zhai Cheng, Zheng Yangfeng, Yu Xu, Xu Jizhao, Sun Yong, Cong Yuzhou, Tang Wei, Li Yujie, Zhu Xinyu, Chen Aikun Aug 2022

Experimental Study On The Mechanical Properties Of Coal-Like Materials For Hydraulic Fracturing Simulation, Zhai Cheng, Zheng Yangfeng, Yu Xu, Xu Jizhao, Sun Yong, Cong Yuzhou, Tang Wei, Li Yujie, Zhu Xinyu, Chen Aikun

Coal Geology & Exploration

Simulation experiments on hydraulic fracturing of the coal seam in the laboratory are an effective method to study the mechanism of fracturing and enhancing permeability of coal-rock mass by hydraulic fracturing in coal mines. However, the technology in-situ sampling for large-size coal mass is immature, and the existing large-size coal samples are mostly taken from the stress-relaxation area, which can be further damaged in the transportation and preparation processes, causing large dispersion in test results. Therefore, The use of coal-like materials is a viable option to replace large-size raw coal for hydraulic fracturing simulation experiments. The mechanical properties of coal-like …


High-Efficiency Regional Gas Drainage Model After Hydraulic Fracturing Of Comb-Shaped Long Boreholes In The Roof Of Broken Soft And Low Permeability Coal Seam, Chen Dongdong, Wang Jianli, Jia Bingyi, Xi Jie Aug 2022

High-Efficiency Regional Gas Drainage Model After Hydraulic Fracturing Of Comb-Shaped Long Boreholes In The Roof Of Broken Soft And Low Permeability Coal Seam, Chen Dongdong, Wang Jianli, Jia Bingyi, Xi Jie

Coal Geology & Exploration

Advanced management of gas enrichment area is an important guarantee to realize safe, efficient and intelligent mining in coal mine. Aiming at the problem of high-efficiency gas drainage in broken and soft coal seam region, taking No.3 coal seam in Hancheng mining area as the research object, a gas drainage mode of comb-shaped long borehole hydraulic fracturing in the roof of coal seam is proposed. The applicability of the model is verified by means of theoretical analysis, numerical simulation and field test, and the fracture propagation law, gas drainage mechanism, and fracturing curve features of comb-shaped borehole in adjacent roof …


Experimental Study Of Hydraulic Fracture Evolution With Materials Similar To The Structural Plane, Li Quangui, Wu Xiaobin, Hu Qianting, Liu Le, Shi Jialin, Song Mingyang Aug 2022

Experimental Study Of Hydraulic Fracture Evolution With Materials Similar To The Structural Plane, Li Quangui, Wu Xiaobin, Hu Qianting, Liu Le, Shi Jialin, Song Mingyang

Coal Geology & Exploration

The structural plane extensively occurs in coal measures, and is one of the key factors affecting the hydraulic fracturing effect of coal/rock. The fabrication time and filling material types of the structural plane were adjusted to obtain the coal/rock specimens without the filling structural plane, or the coal/rock specimens with the filling structural plane. The physical experiment for hydraulic fracturing was carried out to find out the effect and action mechanism of the structural plane type and injected flow rate on hydraulic fracture extension. As indicated by the result, in the condition of the injected flow rate of 50 mL/min, …


Mesoscopic Law Of Stress And Fracture Evolution Of Coal Seams Hydraulic Fracturing, Li Quangui, Deng Yize, Hu Qianting, Zhang Yuebing, Song Mingyang, Liu Jichuan, Shi Jialin Jun 2022

Mesoscopic Law Of Stress And Fracture Evolution Of Coal Seams Hydraulic Fracturing, Li Quangui, Deng Yize, Hu Qianting, Zhang Yuebing, Song Mingyang, Liu Jichuan, Shi Jialin

Coal Geology & Exploration

Hydraulic fracturing is a technology to increase coal seam permeability, and its stress evolution characteristics and the judgment of fracture morphology and propagation range are particularly important. In this paper, based on directional fracturing, a fluid-structure coupling model of hydraulic fracturing is established by using the discrete element numerical method. The effects of fracturing flow, Poisson’s ratio, natural fracture density on stress evolution and fracture evolution, and their mesoscopic laws are investigated by means of the stress path and crack hot spot diagram. The results show that the stress evolution direction and the final stress path curve shape are obviously …


Evaluation Method And Application Of Fracturing Effect Based On Dynamic Permeability Change Of Coal Reservoir Hydraulic Fracturing, Shan Tuo, Sun Changyan, Wang Qian, Xie Xiangjun, Fan Yigang May 2022

Evaluation Method And Application Of Fracturing Effect Based On Dynamic Permeability Change Of Coal Reservoir Hydraulic Fracturing, Shan Tuo, Sun Changyan, Wang Qian, Xie Xiangjun, Fan Yigang

Coal Geology & Exploration

The fracturing construction curve is considered to be an important basis for reflecting the fracturing effect, while the dynamic change of reservoir permeability in the fracturing stage can more intuitively reflect the effect of fracture formation. In this paper, a quantitative evaluation method for reservoir dynamic permeability in fracturing stage was established based on the principle of well testing. Then, the method was applied to evaluate the fracturing effect of two coalbed methane (CBM) wells in a block in southern Junggar Basin, and the dynamic permeability curve of reservoir during fracturing stage is obtained. Meanwhile, the G-function method was …


Application Of Advanced Regional Treatment Technology Of Hard Roof In Buertai Coal Mine Of Shendong Coal Group, Yang Junzhe, Wang Zhenrong, Lyu Qingxu, Yang Sen, Li Guo, Zheng Kaige Feb 2022

Application Of Advanced Regional Treatment Technology Of Hard Roof In Buertai Coal Mine Of Shendong Coal Group, Yang Junzhe, Wang Zhenrong, Lyu Qingxu, Yang Sen, Li Guo, Zheng Kaige

Coal Geology & Exploration

The hard roof is a difficult problem in rock stratum control. The breaking and instability of high hard rock strata often induces strong coal pressure disasters, seriously threatening the safety production in coal mines. Hard roof control is one of the major problems in coal mine safety production. In response to the problems of large thickness, high hardness of the coal seam roof and its difficulty in collapse in Buertai Coal Mine in Shendong Mining Area, the hydraulic fracturing mechanism and technical advantages of directional long borehole segmented hydraulic fracturing are analyzed. The location of boreholes is determined based on …