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Process And Mechanism Of Defluorination Using Magnesium Chloride-Modified Coal Gangue, ZHAO Li, ZHOU Wangxu, ZHANG Qing, XING Mingfei, XU Feng, KONG Weifang, LIU Yifei, QIN Guangyu 2025 Henan Key Laboratory of Coal Measure Unconventional Resources Accumulation and Exploitation, School of Resources and Environment, Henan Polytechnic University, Jiaozuo 454003, China; Shaanxi Key Laboratory of Prevention and Control Technology for Coal Mine Water Hazard, Xi’an 710077, China

Process And Mechanism Of Defluorination Using Magnesium Chloride-Modified Coal Gangue, Zhao Li, Zhou Wangxu, Zhang Qing, Xing Mingfei, Xu Feng, Kong Weifang, Liu Yifei, Qin Guangyu

Coal Geology & Exploration

Background The rapid development of industry has resulted in a yearly increase in wastewater discharge, which induces a gradually rising fluorine concentration in water. In this context, removing fluoride using natural materials and industrial waste has emerged as a popular research topic. Coal gangue, one of the largest contributors to industrial waste in China, contains substantial clay minerals, and its pore structure can be effectively improved through modification. This helps significantly enhance its adsorption performance and thus achieve efficient fluoride removal from water. Methods This study investigated coal gangue from a typical mining area of the Henan Energy and Chemical …


A Modular Casing While Drilling Rig For Large-Diameter Horizontal Boreholes For Underground Rescue, FAN Dong, NI Xiaoyang, MU Shuyuan, ZOU Zujie, WEN Guojun, LI Yingping, LU Feifei 2025 College for Elite Engineers, China University of Geosciences, Wuhan 430074, China; CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China

A Modular Casing While Drilling Rig For Large-Diameter Horizontal Boreholes For Underground Rescue, Fan Dong, Ni Xiaoyang, Mu Shuyuan, Zou Zujie, Wen Guojun, Li Yingping, Lu Feifei

Coal Geology & Exploration

Objective Operations in a narrow space pose a challenge to rescue in the case of the collapse of mine roadways or tunnels. To address this challenge, this study developed a modular rescue casing while drilling (CwD) rig system for horizontal boreholes. With the capacity for quick responses, this CwD rig was designed to enhance the rescue efficiency and safety under complex geological conditions. Methods Following the modular design concept and compact layout principle, this study optimized core components such as the power heads, feed devices, and power system. The auxiliary operation vehicle was checked against overturning through multibody dynamics (MBD) …


Structural Optimization For Transfer Chutes Based On Energy Dissipation Mechanisms Of Coal Particles, SHI Yaocheng, ZOU Zujie, WEN Guojun, CHENG Siyi, WU Laijie, WANG Yudan, LIU Pu, CHEN Mengxi 2025 School of Mechanical Engineering and Electronic Information, China University of Geosciences, Wuhan 430074, China

Structural Optimization For Transfer Chutes Based On Energy Dissipation Mechanisms Of Coal Particles, Shi Yaocheng, Zou Zujie, Wen Guojun, Cheng Siyi, Wu Laijie, Wang Yudan, Liu Pu, Chen Mengxi

Coal Geology & Exploration

Objective Bulk material transport in emergency rescue scenarios and coal transportation poses stringent demands for the structural performance of transfer chutes. Given this, from the perspective of the energy dissipation mechanisms of particles, this study proposed structural optimization methods for transfer chutes based on the regulation of particle energy dissipation. Methods An experiment–simulation integrated analysis framework was established. Using this framework, this study systematically simulated the impact process of particles between two-stage walls I and Ⅱ using the discrete element method (DEM), highlighting the coupling mechanisms among velocity fluctuations, stress distribution, and energy transformation pathways. Based on the results, this …


A Simulation And Experimental Study Of Bottomhole Flow Field In A Large-Diameter Rescue Borehole, ZHAO Yan, LIU Songhe, HAO Shijun, ZHAO Jiangpeng, LI Peishu, WANG Xuebo, YU Yongping, GAO Ke, DONG Bo, ZHANG Bo 2025 State Key Laboratory of Deep Earth Exploration and Imaging, Jilin University, Changchun 130061, China; College of Construction Engineering, Jilin University, Changchun 130061, China

A Simulation And Experimental Study Of Bottomhole Flow Field In A Large-Diameter Rescue Borehole, Zhao Yan, Liu Songhe, Hao Shijun, Zhao Jiangpeng, Li Peishu, Wang Xuebo, Yu Yongping, Gao Ke, Dong Bo, Zhang Bo

Coal Geology & Exploration

Objective In mine rescue, reaming using a large-diameter down-the-hole (DTH) hammer faces is challenged by complex bottomhole flow fields and difficult slag discharge. This study aims to address these challenges. Methods To reveal the influence patterns of drilling parameters on the bottomhole flow field and slag discharge efficiency, this study determined the optimal drilling parameter combination. Then, using the computational fluid dynamics (CFD)-discrete phase model (DPM) method, this study established a numerical model for the slag discharge and bottomhole flow field during the reverse circulation drilling using a DTH hammer. Relying on this model, this study analyzed the variation patterns …


Table Of Contents, The Editors 2025 China Coal Technology and Engineering Group (CCTEG)

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Injection-Production Process Parameters Of Well Group Configurations For Autothermic Pyrolysis In Situ Conversion Of Oil Shale, ZENG Yijian, ZHU Chaofan, LI Yanwei, SHUI Haoche, GUO Wei 2025 State Key Laboratory of Deep Earth Exploration and Imaging, College of Construction Engineering, Jilin University, Changchun 130026, China; National-Local Joint Engineering Laboratory of In-situ Conversion, Drilling and Exploitation Technology for Oil Shale, Changchun 130026, China; Provincial and Ministerial Co-construction of Collaborative Innovation Center for Shale Oil & Gas Exploration and Development, Changchun 130026, China; Key Lab of Ministry of Natural Resources for Drilling and Exploitation Technology in Complex Conditions, Changchun 130026, China

Injection-Production Process Parameters Of Well Group Configurations For Autothermic Pyrolysis In Situ Conversion Of Oil Shale, Zeng Yijian, Zhu Chaofan, Li Yanwei, Shui Haoche, Guo Wei

Coal Geology & Exploration

Background A well group acts as a multi-well synergistic unit, and its configuration directly determines both the selection of optimal injection–production process and the utilization efficiency of stratigraphic conditions, ultimately affecting the overall performance of resource recovery. Methods Using numerical simulations, this study assessed the performance of autothermic pyrolysis in situ conversion (ATS) under three vertical well group configurations: one injection well and one production well (1I1P), one injection well surrounded by four production wells (1I4P), and one injection well surrounded by six production wells (1I6P). Furthermore, it revealed the synergistic mechanisms between well group configuration and energy efficiency. Results …


Attenuation Characteristics And Wave Impedance Inversion Of Depth-Domain Nonstationary Seismic Data, MA Ming, MA Feng 2025 Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Xiamen 361000, China; Technology Innovation Center for Geothermal & Hot Dry Rock Exploration and Development, Ministry of Natural Resources, Shijiazhuang 050061, China

Attenuation Characteristics And Wave Impedance Inversion Of Depth-Domain Nonstationary Seismic Data, Ma Ming, Ma Feng

Coal Geology & Exploration

Background The efficient application of depth migration methods has enabled the extensive implementation of depth-domain seismic data interpretation. Previous studies on the impacts of time-to-depth conversion and velocity models merely determine that an increase in depth corresponds to reduced dominant wavenumber of seismic waves and waveform stretching, without considering the changes in amplitude and phase. Objective This study aims to accurately characterize the waveforms of nonstationary seismic signals in the depth domain and enhance the impedance inversion accuracy. Methods First, based on energy dissipation and frequency dispersion effects during the propagation of seismic waves, this study investigated the complex mapping …


Analysis Of The Connotation Of Hidden Disaster-Causing Factors In Coal Mines And The Key Points Of Their Reconnaissance, LIAN Huiqing, WANG Xu, YIN Shangxian, XIA Xiangxue, CAO Min, LI Qixing, WU Xiaoming, ZHANG Bin, WANG Yangyu, ZHANG Qing, WANG Guo’an 2025 Hebei Key Laboratory of Mine Disaster Prevention and Control, North China Institute of Science and Technology, Beijing 101601, China; Hebei Technology Innovation Center for Intelligent Emergency Response to Multi-Scenario Water Disaster Chain Accidents, North China Institute of Science and Technology, Beijing 101601, China

Analysis Of The Connotation Of Hidden Disaster-Causing Factors In Coal Mines And The Key Points Of Their Reconnaissance, Lian Huiqing, Wang Xu, Yin Shangxian, Xia Xiangxue, Cao Min, Li Qixing, Wu Xiaoming, Zhang Bin, Wang Yangyu, Zhang Qing, Wang Guo’An

Coal Geology & Exploration

Background To systematically normalize the reconnaissance of hidden disaster-causing factors in coal mines, the National Mine Safety Administration issued the Specification for General Survey of Hidden Disaster-causing Factors in Mine in 2024. Nevertheless, coal mining enterprises still face a range of notable issues in reconnaissance of hidden disaster-causing factors, including ambiguous connotations of the factors, broad scopes of reconnaissance, unclear implementation stages, a disjunction between explorations and reconnaissance, and improper conclusion descriptions. These problems severely restrict scientific and operational reconnaissance.Methods This study reviews the history of research on the reconnaissance of hidden disaster-causing factors, presents a summary of significant …


Molecular Simulations Of Selective Adsorption Of Lithium In The No.6 Coal Seam, Junggar Coalfield, ZHANG Junshuang, SUN Beilei, ZHANG Bin, LIU Chao 2025 College of Geological and Surveying Engineering, Taiyuan University of Technology, Taiyuan 030024, China

Molecular Simulations Of Selective Adsorption Of Lithium In The No.6 Coal Seam, Junggar Coalfield, Zhang Junshuang, Sun Beilei, Zhang Bin, Liu Chao

Coal Geology & Exploration

Objective With the discovery of metal deposits in coal-bearing strata, the distribution and occurrence patterns of lithium in coals have attracted much attention. However, its partitioning mode between organic structures and minerals in coals remains poorly understood.Methods This study investigated typical coals with a high lithium content in the Junggar Coalfield in Inner Mongolia. By integrating multiple simulation methods, including quantum mechanics, Monte Carlo simulation, and molecular dynamics, this study established the structural models of organic matter and inorganic minerals, as well as a visualized lithium-coal molecular structure model. Accordingly, it investigated the preferential adsorption sites on both organic …


Molecular Simulation Of Adsorption And Diffusion Behaviors Of High-Concentration Helium In Salt Cavern Storage Reservoirs, CHEN Zeya, WANYAN Qiqi, LIU Mancang, LIU Xiaoqiang, CHEN Jianfa, LI Kang, WU Jianan, YOU Bing 2025 National Energy Underground Gas Storage Research and Development Center, Langfang 065007, China; PetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, China

Molecular Simulation Of Adsorption And Diffusion Behaviors Of High-Concentration Helium In Salt Cavern Storage Reservoirs, Chen Zeya, Wanyan Qiqi, Liu Mancang, Liu Xiaoqiang, Chen Jianfa, Li Kang, Wu Jianan, You Bing

Coal Geology & Exploration

Background Artificial salt cavern underground helium storage is the optimal approach for achieving long-term, large-scale strategic helium storage and represents an essential solution for establishing an autonomous, controllable helium supply system. The core challenge currently constraining China’s development of salt cavern underground helium storage facilities lies in the sealing capacity of salt rock against high-concentration helium (helium volume fraction ≥70%). Methods Molecular dynamics simulation was used in this study, a composite model of salt rock slit pore and channel pore was constructed to reveal the influences of temperature-pressure conditions, helium concentration, and pore fluid properties on the occurrence state and …


Source And Primary Factors Controlling Differential Enrichment For Helium In The Dongping Gas Field, Qaidam Basin, XU Zhusong, LI Jian, WANG Xiaobo, CUI Huiying, XIA Yutian, TIAN Jixian, LI Wanting, CHEN Dawei 2025 Research Institute of Science and Technology, CNPC, Beijing 100083, China; Research Institute of Petroleum Exploration and Development, CNPC, Beijing 100083, China; Key Laboratory of Gas Reservoir Formation and Development, CNPC, Langfang 065007, China

Source And Primary Factors Controlling Differential Enrichment For Helium In The Dongping Gas Field, Qaidam Basin, Xu Zhusong, Li Jian, Wang Xiaobo, Cui Huiying, Xia Yutian, Tian Jixian, Li Wanting, Chen Dawei

Coal Geology & Exploration

Background In recent years, promising helium-rich natural gas shows have been discovered in the Dongping gas field. However, the helium resources in the gas field exhibit lateral heterogeneity and vertical differential accumulation in multiple sequences, which restrict the further exploration of these resources. Methods By analyzing the lateral and vertical distribution characteristics of helium in the Dongping gas field, this study explored its origin and sources, analyzed the differences in geological backgrounds between helium-rich and helium-deficient gas reservoirs, and systematically summarized the differential enrichment pattern across different blocks within the Dongping gas field.Results and Conclusions In the Dongping gas …


Water Filling Intensity Assessment Of A Coal Seam Roof In The Dahaize Coal Mine, Northern Ordos Basin, LIU Xi, DING Xiang, HUANG Haiyu, LI Zhaoyang, LI Zhe, ZHENG Sheng 2025 China Coal Energy Research Institute Co., Ltd., Xi’an 710054, China

Water Filling Intensity Assessment Of A Coal Seam Roof In The Dahaize Coal Mine, Northern Ordos Basin, Liu Xi, Ding Xiang, Huang Haiyu, Li Zhaoyang, Li Zhe, Zheng Sheng

Coal Geology & Exploration

Background Assessing water filling intensity in coal seam floors lays a foundation for the prevention and control of water hazards in mines. However, in the Jurassic coalfield in the northern Ordos Basin, complex hydrogeological structures and sedimentary heterogeneity pose severe challenges to traditional evaluation methods. Methods This study investigated the water hazard characteristics in the superimposed aquifers of the Jurassic Yan’an and Zhiluo formations in the Dahaize Coal Mine in northern Shaanxi. The purpose is to establish a zoning and assessment system of water filling intensity that is suitable for continental sedimentary settings and to provide a scientific basis for …


Characteristics And Formation Processes Of Helium-Bearing Gas Reservoirs In Deep Strata In The Xujiaweizi Fault Depression, Songliao Basin, REN Jiahao, HE Yanxin, TIAN Wei, WANG Lei 2025 School of Earth and Space Sciences, Peking University, Beijing 100871, China

Characteristics And Formation Processes Of Helium-Bearing Gas Reservoirs In Deep Strata In The Xujiaweizi Fault Depression, Songliao Basin, Ren Jiahao, He Yanxin, Tian Wei, Wang Lei

Coal Geology & Exploration

Objective and Method The Xujiaweizi Fault Depression in the Songliao Basin contains multiple helium-bearing gas fields. However, the assessment methods for helium resources and helium accumulation patterns in the fault depression are yet to be determined. Using 3D seismic data and logs from 24 wells, this study optimized the helium resource assessment method based on natural gamma-ray spectral logging. Using the optimized method, this study quantitatively assessed the helium-generating potential and theoretical helium production of crust-derived helium in deep strata in the Xujiaweizi Fault Depression. By combining the geochemical characteristics of the helium-bearing gas reservoirs and the simulation results of …


Diagnosis, Prevention, And Control Of Liquid Accumulation In Horizontal Wellbores For Deep Coalbed Methane: A Case Study Of The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, ZENG Wenting, WANG Zhiming, ZHANG Lei, TIAN Zhida, ZHEN Huaibin, DAI Anna, ZENG Quanshu, SUI Tianyang 2025 College of Petroleum Engineering, China University of Petroleum (Beijing), Beijing 102299, China; National Engineering Research Center of China United Coalbed Methane Co., Ltd., Beijing 100095, China

Diagnosis, Prevention, And Control Of Liquid Accumulation In Horizontal Wellbores For Deep Coalbed Methane: A Case Study Of The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Zeng Wenting, Wang Zhiming, Zhang Lei, Tian Zhida, Zhen Huaibin, Dai Anna, Zeng Quanshu, Sui Tianyang

Coal Geology & Exploration

Objective The Daning-Jixian block on the eastern margin of the Ordos Basin has achieved large-scale production of deep coalbed methane (CBM), with nearly 150 horizontal wells having been put into production. However, with a gradual decrease in formation energy during CBM production, gas wells exhibit declining liquid-carrying capacity. Consequently, liquid accumulation in wellbores has become a major factor affecting deep CBM production. Recovery of deep CBM shows the coexistence of free and desorbed gases, accompanied by significantly varying gas/liquid ratios. Moreover, gas production channels and techniques vary in different production stages. Hence, there is an urgent need to develop a …


A New Genesis Method-Based Methodology For Helium Resource Evaluation: Application To The Jinzhong Basin And Its Geological Implications, ZHANG Qiao, ZHOU Junlin, MA Shangwei, GUO Wang, LI Yuhong, ZHANG Yunpeng, ZHANG Yuxuan, XU Haihong, WANG Jiawei 2025 Xi’an Center, China Geology Survey, Geosciences Innovation Center of Northwest China, Xi’an 710119, China; Research Center for Helium, China Geology Survey, Xi’an 710119 China

A New Genesis Method-Based Methodology For Helium Resource Evaluation: Application To The Jinzhong Basin And Its Geological Implications, Zhang Qiao, Zhou Junlin, Ma Shangwei, Guo Wang, Li Yuhong, Zhang Yunpeng, Zhang Yuxuan, Xu Haihong, Wang Jiawei

Coal Geology & Exploration

Background Helium, a strategic resource in short supply, primarily occurs in natural gas. In China, helium resource assessment remains in its nascent stage, and limited helium exploration and exploitation have been conducted in general. Most especially, for regions experiencing no natural gas exploration and basins where helium reserves remain unproven, it is essential to develop reliable methods for helium resource evaluation. Among various approaches, genesis methods, based on models of helium generation, migration, and enrichment processes, offer advantages including simple models, accessible parameters, and rapid assessment. However, existing genesis methods focus primarily on the estimation of the total amount of …


Sedimentary Environments And Microscopic Water Control Patterns In The Luohe Formation, Gaojiapu Coal Mine, Binchang Mining Area, LI Xiaolong 2025 1CCTEG Xi’an Research Institute (Group) Co. Ltd., Xi’an 710077, China; Shaanxi Provincial Geological Survey Institute, Xi’an 710004, China; College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; Water Disaster Control Branch Laboratory, National Key Laboratory of Coal Mine Disaster Prevention and Control, Xi’an 710077, China

Sedimentary Environments And Microscopic Water Control Patterns In The Luohe Formation, Gaojiapu Coal Mine, Binchang Mining Area, Li Xiaolong

Coal Geology & Exploration

Objective and Method The exploration of the Luohe Formation, located on the roof of the Huanglong Jurassic coalfield, faces challenges such as a lack of consensus on the sedimentary environments of sandstone aquifers and unclear lithologies with water yield properties in the aquifers. To address these challenges, this study investigated sandstones in the Luohe Formation in the Gaojiapu Coal Mine, Shaanxi Province. Specifically, a comprehensive analysis of core samples with different lithologies was conducted, including colors, lithologies, lithologic assemblages, the surface morphology of quartz grains, mineral components, and sedimentary structures and textures. Based on analytical results, as well as the …


Geothermal Resource Assessment Of The Eastern Da’An Area Based On 3d Geothermal Geological Modeling, CHEN Wenwen, RAO Song, MENG Boyan, GUO Menghao, LUO Yang, CAI Jiahao, LI Wenjing, ZHANG Qiaoran, TANG Yucong 2025 School of Geosciences, Yangtze University, Wuhan 430100, China; Hubei Key Laboratory of Complex Shale Oil and Gas Geology and Development in Southern China, Yangtze University, Wuhan 430100, China

Geothermal Resource Assessment Of The Eastern Da’An Area Based On 3d Geothermal Geological Modeling, Chen Wenwen, Rao Song, Meng Boyan, Guo Menghao, Luo Yang, Cai Jiahao, Li Wenjing, Zhang Qiaoran, Tang Yucong

Coal Geology & Exploration

Objective The Da’an area in Jilin Province, located in the southwestern Central Depression of the Songliao Basin, exhibits significant geothermal anomalies, which suggest substantial potential for geothermal exploitation. However, there remains a lack of detailed geothermal resource assessment of this area. Among conventional assessment methodologies, the volumetric method fails to accurately characterize irregular stratigraphic geometries and the spatial heterogeneity of parameters, while the Monte Carlo method suffers from limitations such as heavy dependence on the probability distribution models of geothermal reservoir parameters. Methods To overcome the limitations of the conventional methods, this study established a 3D geothermal geological model by …


A Collocation Point Sampling Method For Solving The Helmholtz Equation Using Physics-Informed Neural Networks, SHAN Lianpu, YU Caixia, WANG Yanfei 2025 Key Laboratory of Deep Petroleum Intelligent Exploration and Development, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China

A Collocation Point Sampling Method For Solving The Helmholtz Equation Using Physics-Informed Neural Networks, Shan Lianpu, Yu Caixia, Wang Yanfei

Coal Geology & Exploration

Background In the field of seismic wavefield simulation, physics-informed neural networks (PINNs) have emerged as a new method for efficiently solving the Helmholtz equation due to their characteristic of grid-free computation. However, for the forward modeling of complex medium models using the Helmholtz equation, traditional uniform grid-based methods for collocation point sampling are insufficient to efficiently provide gradient information, leading to prolonged training time and high resource consumption. Objective and Method To improve the forward modeling efficiency and accuracy based on PINNs and overcome the anomalous concentration of collocation points in the seismic source during dynamic sampling, this study proposed …


Anomalous Responses Of Coal Seam Mining Face Floor Derived Based On Stress-Induced Failure Modeling And 3d Direct Current Electric Method, GAO Weifu, ZOU Xu, NIU Chao, XIAO Lele, ZI Jianxiao 2025 College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China

Anomalous Responses Of Coal Seam Mining Face Floor Derived Based On Stress-Induced Failure Modeling And 3d Direct Current Electric Method, Gao Weifu, Zou Xu, Niu Chao, Xiao Lele, Zi Jianxiao

Coal Geology & Exploration

Objective In recent years, floor water inrushes have frequently occurred in North China-type coalfields. To address this challenge, determining the anomalous responses of water inrushes from stope floors has emerged as a focus of research on water disaster prevention and control. Methods This study established a stress model of the stope floor based on the mine pressure theory. Using this model, it analyzed the stress distribution and failure characteristics of the stope floor. The floor failure characteristics revealed that the coal seam floor can be divided into three zones: the compression, expansion, and recovery zones. Through stress-resistivity tests, this study …


Technologies And Equipment For Efficient Drilling Rescue, YAO Ningping, ZOU Zujie, ZHANG Zhonghai, ZHAO Jiyun, HAO Shijun, FAN Dong, DOU Bin 2025 CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China

Technologies And Equipment For Efficient Drilling Rescue, Yao Ningping, Zou Zujie, Zhang Zhonghai, Zhao Jiyun, Hao Shijun, Fan Dong, Dou Bin

Coal Geology & Exploration

Objective In China, mining operations are progressively extending to greater depths, with annual tunneling of mine roadways and tunnels nationwide reaching nearly 20000 km. In this context, mine (tunnel) accidents occur frequently, threatening the safety of state property and people’s lives. To meet the great demand for emergency rescue in mine (tunnel) accidents, drilling rescue, emerging as a hot topic, has been employed as an effective approach. Methods Techniques and equipment for efficient and safe drilling of surface and underground (tunnel) rescue boreholes were investigated by centering on two main roadmaps: (1) surface rescue equipment – forming techniques for search …


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