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Full-Text Articles in Mining Engineering
Occurrence Pattern Of Adsorbed And Free Gas In Deep Coal Seams Under The Control Of Pore Structure: A Case Study Of The No. 8 Coal Seam In The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Bian Liheng, Shen Jian, Shi Rui, Zhang Wei, Ma Zhuang, Liang Xuemin, Dong Jiying, Zhu Peipei, Ma Tianyu
Occurrence Pattern Of Adsorbed And Free Gas In Deep Coal Seams Under The Control Of Pore Structure: A Case Study Of The No. 8 Coal Seam In The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Bian Liheng, Shen Jian, Shi Rui, Zhang Wei, Ma Zhuang, Liang Xuemin, Dong Jiying, Zhu Peipei, Ma Tianyu
Coal Geology & Exploration
Background Deep coalbed methane (CBM) holds an important strategic position in China's unconventional natural gas system. However, concerning deep CBM occurrence, there remains a lack of systematic quantitative understanding of the underlying mechanisms and the controlling effects of pore structure. Methods This study investigated high-rank coal samples collected at a burial depth of approximately 2000 m from the No. 8 coal seam in the Daning-Jixian block along the eastern margin of the Ordos Basin. Using multiscale pore characterization techniques, including low-temperature liquid nitrogen adsorption, high-pressure mercury injection, and low-temperature CO2 adsorption, the full-scale pore size distribution of the coal …
Mechanisms Behind The Controlling Effects Of Temperature-Pressure Conditions On The Dynamic Ch4–H2O Production From Bituminous Coal, Zhang Hewei, Shen Jian, Li Kexin, Wu Caifang
Mechanisms Behind The Controlling Effects Of Temperature-Pressure Conditions On The Dynamic Ch4–H2O Production From Bituminous Coal, Zhang Hewei, Shen Jian, Li Kexin, Wu Caifang
Coal Geology & Exploration
Background For deep coalbed methane (CBM) exploitation, the temperature-pressure synergistic effect in the CH4-H2O two-phase flow remains poorly understood, restricting the establishment of efficient CBM production systems.Methods This study investigated the No.13 coal seam in the Guanjiaya Coal Mine along the eastern margin of the Ordos Basin. Using low-field nuclear magnetic resonance (LF-NMR) and nuclear magnetic resonance imaging (NMRI) techniques, this study explored the dynamic process of CH4 displacing water and associated gas-water production mechanisms under different displacement pressures (2‒8 MPa) and temperatures (25 ℃ and 60 ℃).Results and Conclusions The sample used …
Mechanisms Behind Permeability Enhancement Of Coal Reservoirs Induced By Electro-Chemical Composite Energy Pulse Fracturing, Meng Bingbing, Cao Yunxing, Duan Hongfei, Zhang Xinsheng, Zhao Lijuan, Shi Bin, Yu Guofeng
Mechanisms Behind Permeability Enhancement Of Coal Reservoirs Induced By Electro-Chemical Composite Energy Pulse Fracturing, Meng Bingbing, Cao Yunxing, Duan Hongfei, Zhang Xinsheng, Zhao Lijuan, Shi Bin, Yu Guofeng
Coal Geology & Exploration
Background Electro-chemical composite energy pulse fracturing (ECCE-PF) technology (i.e., the electrical explosion of metal wires igniting energetic materials) can effectively change the pore structure of coal reservoirs and enhance coal seam permeability. Elucidating the mechanisms behind the influence of this technology on both the scales of modified coal pores/fractures and methane desorption pattern can provide a theoretical basis for the wide application of this technology to coal seam permeability enhancement. Methods This study investigated coal samples from the Zhangcun Coal Mine in the Lu’an coal mining area, Shanxi Province. Using a self-developed ECCE-PF experimental platform, an experimental study was conducted …
Evolutionary Mechanisms Of Nanopores And Adsorption Capacity In Shales Under Scco2-Water-Rock Interactions, Feng Guangjun, Wang Meng, Zhu Yanming, Song Yu, Dai Xuguang, Zheng Sijian, Xie Hong, Shang Fuhua
Evolutionary Mechanisms Of Nanopores And Adsorption Capacity In Shales Under Scco2-Water-Rock Interactions, Feng Guangjun, Wang Meng, Zhu Yanming, Song Yu, Dai Xuguang, Zheng Sijian, Xie Hong, Shang Fuhua
Coal Geology & Exploration
Background Supercritical carbon dioxide (ScCO2 )-enhanced shale oil and gas recovery serves as an effective approach to geologic CO2 sequestration. Injecting ScCO2 into shale reservoirs can trigger complex ScCO2-water-rock interactions, thereby altering the material composition, nanopore structure, and adsorption capacity of shales. Examining their evolutionary processes represents a critical scientific issue in the evaluation of CO2 sequestration efficiency. Methods This study investigated the shales of the Longmaxi Formation in the southeastern Chongqing area. Through simulation experiments on ScCO2-water-rock interactions and by integrating X-ray diffraction (XRD), low-pressure CO2/N2 adsorption, fractal …
Structural Evolution And Spontaneous Combustion And Activation Mechanisms Of Coals Treated Under Inert Atmospheres In A Coal Mine Goaf, Zhang Leilin, Li Wanting, Wen Chenchen
Structural Evolution And Spontaneous Combustion And Activation Mechanisms Of Coals Treated Under Inert Atmospheres In A Coal Mine Goaf, Zhang Leilin, Li Wanting, Wen Chenchen
Coal Geology & Exploration
Objective When used for the treatment of fire zones in deep coal mine goafs, low-oxygen and inertization techniques suffer from a scientifically blind spot, i.e., the fire prevention and control bottleneck caused by a high susceptibility to re-ignition of coals after being treated with high-temperature, low-oxygen (or inert) gas. To overcome this limitation, this study aims to systematically determine the mechanisms by which the evolution of the physical and chemical structures of coals after heat treatment under different atmospheres influences their spontaneous combustion and activation behavior. The purpose is to provide theoretical support for the treatment and safe opening of …
Co2-Water Displacement Characteristics Of Saturated Sandstones With Different Pore Structures, Liu Ting, Li Jinglin, Li Yi, Dan Wendong, Diao Yujie, Ma Xin
Co2-Water Displacement Characteristics Of Saturated Sandstones With Different Pore Structures, Liu Ting, Li Jinglin, Li Yi, Dan Wendong, Diao Yujie, Ma Xin
Coal Geology & Exploration
Objective The pore structures of clastics play a crucial role in assessing the potential of saline aquifers for geologic CO2 sequestration. Current studies on pore structures during CO2 sequestration focus primarily on artificial cores. However, compared to artificial cores, natural cores feature more complex pore size distributions and stronger heterogeneity. Methods This study examined a natural core from deep reservoirs in the Ordos Basin and two artificial cores with different porosities through CO2-water displacement experiments under water-saturated conditions. Using a nuclear magnetic resonance (NMR) analysis and imaging system for multiphase fluid displacement, this study analyzed the …
Mechanisms Underlying The Impacts Of Reservoir Pore Structures On Near-Well Salt Precipitation In Co2 Geological Storage, Deng Chenguang, Sun Xiaolong, Liu Keyu, An Senyou, Yuan Guanghui, Wang Yuxiang
Mechanisms Underlying The Impacts Of Reservoir Pore Structures On Near-Well Salt Precipitation In Co2 Geological Storage, Deng Chenguang, Sun Xiaolong, Liu Keyu, An Senyou, Yuan Guanghui, Wang Yuxiang
Coal Geology & Exploration
Objective and Method High CO2 injectivity in reservoirs is essential for high-quality sites of CO2 geological storage (CGS). Salt precipitation in the vicinity of injection wells due to brine dissolution in CO2 emerges as a critical factor impairing CO2 injectivity. To explore the differences in the mechanisms behind salt precipitation and damage degree across various reservoirs, this study conducted salt precipitation simulation experiments on sandstone samples with distinct pore structures using a high-temperature and high-pressure fluid displacement system. By combining methods such as cast thin section observations, scanning electron microscopy and resulting spectra, micro-X-ray fluorescence (micro-XRF) …
Influencing Patterns Of Low-Temperature Nitrogen On The Pore Structure And Oxidation Characteristics Of Lignite, Xie Shuliang, Wang Gang, Qu Qingdong, Liu Hao, Sun Lulu
Influencing Patterns Of Low-Temperature Nitrogen On The Pore Structure And Oxidation Characteristics Of Lignite, Xie Shuliang, Wang Gang, Qu Qingdong, Liu Hao, Sun Lulu
Coal Geology & Exploration
Objective During fire prevention and extinguishment for mines, injecting normal-temperature nitrogen into goaves can only play an inerting role. Meanwhile, the preparation of liquid nitrogen is complicated and costly. Therefore, in the Wudong Coal Mine in Xinjiang, low-temperature gaseous nitrogen of –40 ℃ was prepared using nitrogen cooling devices and then injected into goaves to prevent the spontaneous combustion of residual coals. However, the influencing patterns of low-temperature nitrogen on the pore structures and oxidation characteristics of residual coals in goaves remain poorly understood. This tends to affect the prediction and forecast of the secondary oxidation of residual coals in …
Influencing Mechanisms Of Microwave Radiation Duration On The Efficiency Of Methane Adsorption In Coals, Hu Yiliang, Bao Yuan, Meng Jiahao, Chen Xueru, Shan Tuo
Influencing Mechanisms Of Microwave Radiation Duration On The Efficiency Of Methane Adsorption In Coals, Hu Yiliang, Bao Yuan, Meng Jiahao, Chen Xueru, Shan Tuo
Coal Geology & Exploration
Objective Microwave radiation duration represents a critical factor in enhancing coalbed methane (CBM) recovery using microwave-aided methods. However, the influencing mechanism of microwave radiation duration on the efficiency of methane adsorption in coal seams remains unclear. This necessitates delving into the specific effects of microwave radiation duration on the adsorption efficiency and unveiling their intrinsic constraints. Methods This study investigated the No.2 coal seam in the Huangling mining area. The coal samples were irradiated for 0‒18 min using 700 W microwaves. Using experiments and analyses including isothermal adsorption, low-temperature liquid N2 adsorption, and Fourier transform infrared spectroscopy (FTIR), this study …
Coal Gasification Through Microbial Degradation In A Low-Pressure Co2 And H2 Environment: An Experimental Study, Jian Kuo, Fu Xuehai, Liu Mingjie, Liu Jian, Li Jin, Ru Zhongliang, Ji Xiaofeng, Wang Qiang
Coal Gasification Through Microbial Degradation In A Low-Pressure Co2 And H2 Environment: An Experimental Study, Jian Kuo, Fu Xuehai, Liu Mingjie, Liu Jian, Li Jin, Ru Zhongliang, Ji Xiaofeng, Wang Qiang
Coal Geology & Exploration
Objective and Methods This study aims to investigate the characteristics of CO2 biomethanation and coal gasification through microbial degradation in a low-pressure environment. With low-rank bituminous coals (Rmax = 0.67%) as fermentable substrates, this study conducted a 96-day gas production experiment through microbial fermentation in a low-pressure CO2 and H2 environment. Using techniques including gas chromatography, 16S rRNA gene sequencing, and low-temperature liquid nitrogen adsorption, this study delved into the intrinsic variation patterns of biogenic gas production, microbial communities, and coal structures. Results and Conclusions The results indicate that compared to conventional fermentation, the injection …
Influence Mechanisms Of Dynamic Metamorphism On The Evolution Of Micro/Nano Pore Structures In Tectonically Deformed Coals, Liu Hewu, Lyu Xiaoxue, Hou Chenliang, Xiong Zuopeng
Influence Mechanisms Of Dynamic Metamorphism On The Evolution Of Micro/Nano Pore Structures In Tectonically Deformed Coals, Liu Hewu, Lyu Xiaoxue, Hou Chenliang, Xiong Zuopeng
Coal Geology & Exploration
Objective Micro/nano pore structures in coals act as a significant space for gas occurrence. Exploring the evolutionary mechanisms of micro/nano pore structures in tectonically deformed coals (TDCs) under the influence of dynamic metamorphism assists in gaining a deep understanding of the mechanisms underlying coal and gas outbursts. Methods Using CO2 adsorption experiments, Fourier transform infrared (FTIR) spectroscopy, and molecular dynamics simulations, this study investigated the evolutionary characteristics and mechanisms of micro/nano pore structures in different TDCs occurring within the No.72 coal seam of the Qi’nan Coal Mine in Suzhou Province. Results and Conclusions The results indicate that with enhanced …
Pore Structure And Differential Fluid Occurrence Of Deep Coal Seams, Wu Jian, Sun Qiang, Shi Xuefeng, Gao Lijun
Pore Structure And Differential Fluid Occurrence Of Deep Coal Seams, Wu Jian, Sun Qiang, Shi Xuefeng, Gao Lijun
Coal Geology & Exploration
Objective Breakthroughs have been achieved in deep coalbed methane (CBM) exploration along the eastern margin of the Ordos Basin, exhibiting the characteristics of local breakthroughs but regional differential CBM production in multiple blocks. The pores and fractures in deep coal reservoirs, serving as the material spaces for fluid occurrence and occurrence, are critical to the differential development across deep CBM blocks. Methods In this study, coal samples were collected systematically from the deep part of the Shenfu block located along the eastern margin of the Ordos Basin. Using conventional tests on porosity, permeability, and physical properties, as well as CO …
Impacts Of The Caking Property Of Tar-Rich Coals On Their Pore Structure Evolution And Seepage During Pyrolysis, Chang Zhibing, Wang Chuchu, Kuang Wenhao, Tang Ying, Wu Xiaodan, Liu Shuqin
Impacts Of The Caking Property Of Tar-Rich Coals On Their Pore Structure Evolution And Seepage During Pyrolysis, Chang Zhibing, Wang Chuchu, Kuang Wenhao, Tang Ying, Wu Xiaodan, Liu Shuqin
Coal Geology & Exploration
Objective The in-situ pyrolysis of tar-rich coals stands as a technique whereby coal seams are heated underground to produce tar and gas products. During the in-situ pyrolysis, the injection of heating media and the production of tar and gas are affected by the pore structure and permeability of coal seams. Since pyrolysis of caking tar-rich coals is accompanied by the formation of colloids, the pore structure and permeability of caking tar-rich coals differ from those of non-caking tar-rich coals. Methods Caking tar-rich coals were pyrolyzed at 300, 400, 500, and 600 ℃. During the pyrolysis, the pore parameters of the …
A Preliminary Study Of Coalbed Methane Adsorption At Fractal Interfaces, Jin Yi, Li Yani, Song Huibo, Zhao Mengyu, Yang Yunhang, Chen Zenan
A Preliminary Study Of Coalbed Methane Adsorption At Fractal Interfaces, Jin Yi, Li Yani, Song Huibo, Zhao Mengyu, Yang Yunhang, Chen Zenan
Coal Geology & Exploration
The adsorption and desorption mechanisms of coalbed methane (CBM) are foundational for revealing CBM accumulation mechanisms and achieving efficient CBM exploitation. Studies have indicated that coal reservoirs exhibit complex pore structures with fractal features, significantly influencing CBM adsorption at pore-solid interfaces. Based on a comparative analysis of several common adsorption models for gas-solid interfaces and a summary of their characteristics and applicable conditions, this study suggests that all these adsorption models still rely on the stationary assumption of adsorption selectivity for the description and application of CBM adsorption behavior at fractal interfaces while overlooking the scale invariance of the adsorption …
Exploring The Pore Structure Of Reconstructed Soils And Its Effects On Water And Salt Transport Based On Ct Scanning, Li Huakun, Zheng Liugen, Chen Yongchun, Li Bing, Tao Pengfei, Li Hao
Exploring The Pore Structure Of Reconstructed Soils And Its Effects On Water And Salt Transport Based On Ct Scanning, Li Huakun, Zheng Liugen, Chen Yongchun, Li Bing, Tao Pengfei, Li Hao
Coal Geology & Exploration
Coal gangue serves as a critical material for landfilling and reclamation in the subsidence areas of coal mines. However, due to its rough textures and poor water-holding capacity, soils reconstructed using coal gangue exhibit somewhat different pore structures and water-salt transport from undisturbed soils. To explore the changes in the pore structure of the reconstructed soils and their effects on water and salt transport, this study analyzed the differences in the pore structures between four samples from undisturbed soils, the overburden, mud-gangue mixtures, and gangue using CT scanning and image analysis. Furthermore, an indoor experimental device was designed to simulate …
Gas Expansion Energy Of Coals With Different Metamorphic Degrees: Evolutionary Characteristics And Their Implications For The Outburst Prediction, Liu Gaofeng, Li Baolin, Zhang Zhen, Liu Huan, Guan Wenbo, Si Nian
Gas Expansion Energy Of Coals With Different Metamorphic Degrees: Evolutionary Characteristics And Their Implications For The Outburst Prediction, Liu Gaofeng, Li Baolin, Zhang Zhen, Liu Huan, Guan Wenbo, Si Nian
Coal Geology & Exploration
To achieve an elevated accuracy in the prediction of coal and gas outbursts, this study conducted mercury injection capillary pressure (MICP) tests and isotherm adsorption experiments on selected six coal samples with different metamorphic degrees. Furthermore, it calculated the gas expansion energy of coals and analyzed the evolutionary characteristics of the gas expansion energy of coals with different metamorphic degrees, as well as their relationships with the prediction indices of coal and gas outbursts. The results of this study are as follows: (1) The differences in the pore structures and adsorptivity of coals with different metamorphic degrees led to different …
Reliability Analysis And Compressibility Correction Of Mercury Intrusion Porosimetry Experiments For Low-Medium-Rank Coals, Song Dangyu, Zhao Yuwei, Li Yunbo, Yu Zhen
Reliability Analysis And Compressibility Correction Of Mercury Intrusion Porosimetry Experiments For Low-Medium-Rank Coals, Song Dangyu, Zhao Yuwei, Li Yunbo, Yu Zhen
Coal Geology & Exploration
Low-medium-rank coals are soft and exhibit significant compressibility under high pressure. Therefore, it is debatable whether the pore structure of low-medium-rank coals can be reliably determined using mercury intrusion porosimetry (MIP) experiments. In this study, MIP experiments were conducted on four samples of low-medium-rank coals. By comparing the mercury injection curves of samples with different particle sizes, as well as the macroscopic and microscopic characteristics of the samples before and after mercury injection, this study established a correction method for the mercury injection volume at the high-pressure stage and investigated the reliability of MIP experiments in determining the pore structure …
Influencing Mechanisms Of Sc-Co2 Extraction On The Microstructures Of High-Rank Tectonic Coals, Zhang Xiaodong, Zhang Yu, Zhang Shuo, Li Guizhong, Li Xianzhong
Influencing Mechanisms Of Sc-Co2 Extraction On The Microstructures Of High-Rank Tectonic Coals, Zhang Xiaodong, Zhang Yu, Zhang Shuo, Li Guizhong, Li Xianzhong
Coal Geology & Exploration
This study aims to reveal the influencing patterns of supercritical CO2 (SC-CO2) on the microstructures of tectonic coals during the injection of CO2 into deep coal seams. The study conducted SC-CO2 extraction experiments on two types of high-rank coal samples with different damage degrees, namely the lean coal samples from the Daping coal mine in Shanxi Province and the anthracite samples from the Zhenxing coal mine in Guizhou Province. Accordingly, this study compared the parameters of pore structures and aromatic carbon stacking structures in the coal samples before and after the extraction experiments. Finally, this …
Nanopore Structure And Surface Roughness In Brittle Tectonically Deformed Coals Explored By Atomic Force Microscopy, Zhang Ningyuan, Yao Suping
Nanopore Structure And Surface Roughness In Brittle Tectonically Deformed Coals Explored By Atomic Force Microscopy, Zhang Ningyuan, Yao Suping
Coal Geology & Exploration
The pore structure of coal is the key to coalbed methane (CBM) exploration and exploitation, and coal mining safety. Compared to primary coals, tectonically deformed coals (TDCs) have stronger heterogeneity and are of great importance in coal reservoir study. Here, the pore structure and surface roughness of brittle TDCs were obtained with atomic force microscopy (AFM) and NanoScope Analysis and Gwyddion software. The results show that tectonic deformation generally promotes the pore development in brittle TDCs, but the extent of tectonic impact varies greatly among different brittle TDCs. As a result, two stages in brittle TDCs were identified: weak brittle …
Qualitative-Quantitative Multi Scale Characteristics Of Shale Pore Structure From Upper Paleozoic Coal-Measures In Linxing Area, Liu Cheng, Ding Wangui, Zhang Jian, Chen Xin, Wu Peng, Liu Xueqing, Li Yangbing, Ma Litao, Hu Weiqiang, Kong Wei, Li Yong
Qualitative-Quantitative Multi Scale Characteristics Of Shale Pore Structure From Upper Paleozoic Coal-Measures In Linxing Area, Liu Cheng, Ding Wangui, Zhang Jian, Chen Xin, Wu Peng, Liu Xueqing, Li Yangbing, Ma Litao, Hu Weiqiang, Kong Wei, Li Yong
Coal Geology & Exploration
In order to reveal the micro-pore structure characteristics of marine-continental transitional shale and its main controlling factors in the eastern margin of Ordos Basin, and to enrich the understanding of pore development characteristics and pore structure of marine-continental transitional coal-bearing shale in the block, scanning electron microscope, high-pressure mercury injection and liquid nitrogen adsorption analysis were used to characterize the micro-pore structure characteristics of shale in Linxing area. Furthermore, porosity, total content of organic carbon, mineral content, clay relative content and organic matter maturity were tested to study the main controlling factors of development of shale pore structure. The results …
Experimental Study On Multi-Scale Pore Structure Characteristics Of Tar-Rich Coal In Yushenfu Mining Area, Shen Yanjun, Wang Xu, Zhao Chunhu, Wang Shengquan, Guo Chen, Shi Qingmin, Ma Wen
Experimental Study On Multi-Scale Pore Structure Characteristics Of Tar-Rich Coal In Yushenfu Mining Area, Shen Yanjun, Wang Xu, Zhao Chunhu, Wang Shengquan, Guo Chen, Shi Qingmin, Ma Wen
Coal Geology & Exploration
Extracting oil and refining gas from oil-rich coal is an important measure to make up for the shortage of oil and gas supply in China. The research on pore development characteristics and permeability of tar-rich coal will help to better develop and utilize tar-rich coal. Taking the tar-rich coal in Yushenfu mining area as the research object, this paper studies the multi-scale pore structure and the whole segment pore characterization of tar-rich coal by such methods as low-temperature liquid nitrogen adsorption, mercury intrusion porosimetry, nuclear magnetic resonance and gas permeability measurement method. Based on the test results of multi-scale pore …
Effect Of Load On Adsorption Characteristics Of Remolded Coal, Dai Juhua, Wang Zhaofeng, Li Xuechen, Li Yanfei, Yue Jiwei
Effect Of Load On Adsorption Characteristics Of Remolded Coal, Dai Juhua, Wang Zhaofeng, Li Xuechen, Li Yanfei, Yue Jiwei
Coal Geology & Exploration
In view of the difficulty in preparing the coal with broken soft structure intact, it needs to be processed into remolded coal. In order to study the influence of suppression loads on the physical characteristics of coal, the micro-pore structure and adsorption characteristics of remolded coal under different molding loads were discussed based on the pore test experiment of low temperature liquid nitrogen and the methane adsorption experiment of high pressure capacity method. The results show that: The pore volume of micropores and pores decreases slightly with the increase of molding load, the specific surface area increases slightly with the …
Characteristics Of Shale Gas Reservoir In Upper Paleozoic Coal Measures In Yangquan Block, Qinshui Basin, Li Yangyang, Li Xianqing, Zhang Xueqing, Xiao Xianming, Yu Zhenfeng, Wang Baoyu
Characteristics Of Shale Gas Reservoir In Upper Paleozoic Coal Measures In Yangquan Block, Qinshui Basin, Li Yangyang, Li Xianqing, Zhang Xueqing, Xiao Xianming, Yu Zhenfeng, Wang Baoyu
Coal Geology & Exploration
Shale reservoir characteristics are the basic content of shale gas storage capacity evaluation. In order to explore the properties of high-evolved coal-measures shale gas reservoirs and optimize favorable reservoirs, various experimental methods of rock pyrolysis, X-ray diffraction, scanning electron microscopy, high-pressure mercury intrusion, low-temperature N2 and CO2 gas adsorption were applied to the Qinshui Basin. Reservoir characteristics were studied with core samples of coal-measure shale core from the Upper Paleozoic in Yangquan Block. The results show that the Upper Paleozoic coal-measures shale in Yangquan Block of the Qinshui Basin has a high content of organic carbon(average TOC is …
The Characteristics Of Pore Structure And Gas Adsorption For Water-Immersion Coal After Drying, Si Leilei, Xi Yujun, Wang Hongyang, Wen Zhihui, Wei [email protected] Jianping
The Characteristics Of Pore Structure And Gas Adsorption For Water-Immersion Coal After Drying, Si Leilei, Xi Yujun, Wang Hongyang, Wen Zhihui, Wei [email protected] Jianping
Coal Geology & Exploration
In order to investigate the characteristics of pore structure and methane adsorption for water-immersion coal after drying, two coal samples with different ranks were soaked in distilled water for a long time(60 d). Then, the low-temperature N2 adsorption experiments and CO2 adsorption experiments were carried out to investigate the changing rules of pore structure for coal before and after water immersion, and the high-pressure capacity method was used to test the characteristics of methane adsorption. Results showed that the pore volume and specific surface area of coal decreased after water immersion. According to the results of low-temperature N …
Micro-Pore Structure And Fractal Characteristics Of Terrestrial Shales: A Case Study Of Shahezi Formation In Xujiaweizi Fault Depression, Lin Zizhi, Lu Shuangfang, Chang Xiangchun, Li Junqian, Zhang Pengfei, Zhou Nengwu, Zhang Yu, Wang Junjie, Huang Hongsheng
Micro-Pore Structure And Fractal Characteristics Of Terrestrial Shales: A Case Study Of Shahezi Formation In Xujiaweizi Fault Depression, Lin Zizhi, Lu Shuangfang, Chang Xiangchun, Li Junqian, Zhang Pengfei, Zhou Nengwu, Zhang Yu, Wang Junjie, Huang Hongsheng
Coal Geology & Exploration
The pore structure and fractal characteristics of shale are analyzed, and their impacting factors are also revealed using the low temperature nitrogen adsorption-desorption method, combined with scanning electron microscopy, C-S analysis and XRD. The results showed that the mineral compositions of Shahezi Formation continental shales were dominated by clay minerals, quartz and feldspar. The pore types in shales were mainly clay mineral intragranular pores, feldspar dissolution pores and grain edge pore, while the organic pores were not developed. The adsorption isotherms of shales belonged to the type Ⅳ isotherm according to the IUPAC, which develop two types of hysteresis loop, …
Numerical Simulation Of Pore Structure Stress Characteristics Of Coal And Rock Mass, Wang Gang, Jiang Chenghao, Chen Xuechang
Numerical Simulation Of Pore Structure Stress Characteristics Of Coal And Rock Mass, Wang Gang, Jiang Chenghao, Chen Xuechang
Coal Geology & Exploration
In order to explore the stress distribution around the pores of coal and rock mass under different loading modes, the skeleton model of coal and rock mass with different pore shapes was constructed through CT three-dimensional reconstruction technology, and uniaxial and triaxial compression experiment simulations were conducted using ABAQUS software. The results showed that under uniaxial compression, the upper and lower regions of spherical pores showed tensile stress concentration, while the left and right regions showed compressive stress concentration. The stress concentration types in the long and short axis of elliptic pores were distinct with different dip angles. Under uniaxial …
Micro Ct-Based Meticulous Characterization Of Porosity Evolution Of Coal In The Process Of Biodegradation, Dong Zhiwei, Guo Hongyu, Xia Daping, Liu Xile, Bai Yang, Zhao Guojun
Micro Ct-Based Meticulous Characterization Of Porosity Evolution Of Coal In The Process Of Biodegradation, Dong Zhiwei, Guo Hongyu, Xia Daping, Liu Xile, Bai Yang, Zhao Guojun
Coal Geology & Exploration
To explore the bio-permeability enhancing effect via methanogen treatment on different rank coals after anaerobic fermentation, micro-CT was used to analyze the change characteristics of pore structure of coal before and after biodegradation. At the same time, the adsorption characteristics of methanogens on the coal surface after anaerobic biodegradation were observed by scanning electron microscopy to analyze the reasons for the effect difference of biological transformation of different rank coals. The results show that the porosity and total throat length of the coal samples biodegraded increase and the connectivity of the pores is enhanced, it is indicated that coal samples …
Shale Gas Potential Of Yanguanjie Formation And Longtan Formation In Central And Southeastern Hunan Province, Cao Taotao, Deng Mo, Liu Hu, Huang Yanran, Stefan Andrew Hurssthouse
Shale Gas Potential Of Yanguanjie Formation And Longtan Formation In Central And Southeastern Hunan Province, Cao Taotao, Deng Mo, Liu Hu, Huang Yanran, Stefan Andrew Hurssthouse
Coal Geology & Exploration
In order to reveal the shale gas potential and exploration direction of the marine-continental transitional shale in central and southeastern Hunan, samples were collected from the Lower Carboniferous Yanguanjie Formation and Upper Permian Longtan Formation, measurements were conducted on TOC, Rran, kerogen carbon isotope, maceral composition, X-ray diffraction, scanning electron microscopy, porosity, permeability and methane sorption capacity. The results indicate that Yanguanjie Formation and Longtan Formation shale are at the mature stage, and mainly dominated by type Ⅲ kerogen. The Longtan shale generally has higher TOC content, while Yanguanjie shale has usually low TOC content. The minerals are …