Oil, Gas, and Energy Commons^™

Characteristics Of The Pore And Seepage System Of Deep Coalbed Methane In The Baijiahai Uplift, Junggar Basin, Xinjiang, Chen Heqing, Yang Zhaobiao, Li Daoqing, Xu Miaomiao, Liang Yuhui, Liu Changqing, Wang Yuqiang

Coal Geology & Exploration

[Objective] Xinjiang boasts abundant deep coalbed methane (CBM) resources, with Jurassic coal seams in the Baijiahai uplift of the Junggar Basin identified as a favorable target area for deep CBM exploration and exploitation. The pore and seepage system of deep CBM directly determines its recoverability. [Methods] Based on appraisal well Caimei 2-004H drilled the most recently in the Xinjiang oilfield in 2023, this study investigated in detail the pore and seepage system of coals in the Jurassic Xishanyao Formation in the Baijiahai uplift using scanning electron microscopy (SEM) observations, mercury injection capillary pressure (MICP), low-temperature liquid nitrogen adsorption, and carbon …

Impacts Of Observation Line Layout Morphology And Survey Point Missing On The Inversion Of Predicted Parameters Of Mining Subsidence, Guo Qingbiao, Yu Qing, Zheng Meinan, Luo Jin

Coal Geology & Exploration

[Objective] Accurate prediction parameters for mining subsidence are important basis for full cycle green coal mining, while inversion based on the subsidence data of observation lines serves as the main method to obtain these parameters. [Methods] To quantitatively analyze the impacts of the observation line layout morphology and survey point missing on the inversion of prediction parameters for mining subsidence, this study developed a probability integral model-based inversion method for these parameters using the chimpanzee optimization algorithm (ChOA). Using this method combined with digital simulation experiments, this study predicted subsidence parameters under six observation line morphologies and survey point missing …

Fracturing Evolutionary Law And Energy Utilization Efficiency Of Green Sandstones Under Different Loading Rates, Zhao Huanshuai, Pan Yongtai, Qiao Xin, Wang Xingyu, Yu Chao, Huang Jiacheng

Coal Geology & Exploration

[Objective] This study aims to explore the fracturing evolutionary laws and energy utilization efficiency of rocks under different loading rates is a pressing issue in the field of rock fragmentation and processing. [Methods] To this end, the microscopic parameters of green sandstones were calibrated based on laboratory tests, followed by the identification of relationships between the macro- and microscopic mechanical responses of the sandstones. Using Particle Flow Code (PFC), this study investigated the stress-strain curves and stress chain distribution of green sandstones under different loading rates. Then, based on the fracturing and crack characteristics, this study analyzed the fracturing evolutionary …

Hydrochemical Characteristics And Genetic Mechanism Of Geothermal Water In The Wandong Geothermal Area Along The Moxi Fault In Western Sichuan, Huang Xun, Zhang Yunhui, Li Xiao, Lyu Guosen, Guo Hongyang

Coal Geology & Exploration

[Objective] Geothermal energy exploitation is identified as a vital way to achieve the goals of peak carbon dioxide emissions and carbon neutrality. The Moxi fault, located in the southern segment of the Xianshuihe fault zone in western Sichuan, boasts abundant geothermal resources, serving as a significant area for subsequent geothermal energy exploitation. [Methods] This study investigated the hydrogeochemistry of the Wandong geothermal area along the Moxi fault, analyzed the water-rock interaction process in the area based on the hydrochemical correlation, and calculated the reservoir temperatures and the mixing ratios of cold and hot water using geothermometers and the silica-enthalpy mixing …

Experimental Study On The Mechanics And Deformation Failure Characteristics Of Multi-Source Coal-Based Solid Waste Cemented Backfill, Yang Ke, Zhang Jiqiang, He Xiang, Wei Zhen, Zhao Xinyuan

Coal Geology & Exploration

[Objective] In order to study the mechanical properties and deformation failure laws of multi-source coal-based solid waste cemented backfill (CBSWCB), the uniaxial compression, acoustic emission response and microstructure test experiments were carried out with 5 types of typical coal-based waste. [Methods] The factors influencing the uniaxial compressive strength of CBSWCB, as well as their interaction, were analyzed, and a four-dimensional spatial visualization model of the factors influencing the compressive strength based on their interactions was established. Besides, the mechanical evolution characteristics and macroscopic deformation failure laws under uniaxial compression conditions were elaborated by referring to the acoustic emission and microstructure …

Application Of Microseismic Monitoring System For Coal Mines To The Prevention And Control Of Water Disasters On Working Face Roofs, Fan Xin, Cheng Jianyuan, Li Sheng, Duan Jianhua, Fan Tao, Li Bofan, Wang Yanbo

Coal Geology & Exploration

[Objective] Increasing coal mining depth in coal mines has caused increasingly prominent risks of water disasters on working face roofs, which restrict the green, safe, and efficient coal mining in China’s coal mines. Therefore, there is an urgent need for new technologies for the monitoring and early warning of these water disasters. [Methods] This study explored the application of the joint well-ground microseismic monitoring system to the prevention and control of water disasters on working face roofs, achieving transparent, intelligent monitoring and early warning of water disaster risks. In this system, microseismic sensor arrays are arranged on the surface above …

Geological Structures Fine Monitoring Using Seismic-While-Tunneling Technique In Wangpo Mine, Zhao Huibo, Qin Si, Chen Chao, Guan Qi, Zhao Xingwei, Che Jianhang

Coal Geology & Exploration

Traditional tunnel seismic advance detection technology is limited by the use of explosives, the need for mining stoppages, prediction speed, detection range, and capabilities, making it challenging to meet the high-precision geological structure detection requirements of intelligent tunneling faces. In response, the seismic-while-tunneling technique utilizes the vibration of the roadheader cutting the coal wall as the seismic source. This method employs real-time data upload, automatic processing, and dynamic imaging. By leveraging information technology and software support, and utilizing real-time continuous super-saturation stacking supported by massive data, the imaging precision of geological anomalies ahead of the mining face is significantly enhanced. …

Pneumatic Directional Drilling Technology And Equipment For Broken-Soft Coal Seams In Underground Coal Mines, Tian Hongliang, Zhang Jinbao, Wang Li, Fang Jun, Wang Jianqiang

Coal Geology & Exploration

[Objective] The geological conditions of coal seams in China are complex, with a wide distribution of broken-soft coal seams, and a large number of wells have the problems of high gas and coal-gas outburst. Currently, borehole gas drainage is an effective measure for preventing and controlling the gas disasters. [Methods] In response to the problems of uncontrollable drilling trajectory, shallow drilling depth, large blind spots of drainage in conventional rotary drilling process of broken-soft coal seams, as well as multiple stuck drilling accidents, great difficulty in drilling and low drilling efficiency in conventional directional drilling processes, the development history and …

Build-Up Rate Prediction Of Rotary Steerable Tools Based On Delay Differentiation, Li Fei, Zhang Nan

Coal Geology & Exploration

[Objective] Accurate build-up rate prediction of rotary steerable tools is a prerequisite to achieve the precise control of tools. In order to grasp the variation law of the build-up rate of the rotary steerable bottom-hole assembly (RSBHA). [Methods] Based on the structural charaeteristics of the tool, the Euler-Bernoulli beam equation method is used to analyz the forces outing on the composite RSBHA. At the same time, the calculation method of the tool deflection angle in different sections and the bit pre-drilling deflection angle was obtained with consideration to the geometric relationship of the bottom-hole assembly, and the distance between the …

Analysis Of Three-Dimensional Nonlinear Fluid-Solid Coupling Vibration Characteristics Of Coalbed Methane Abandoned Well Plugging String, Xu Zhixin, Wan Jifang, Hong Yi, Liu Hangming, Yi Xianzhong, Diao Binbin, Wang Yanbin

Coal Geology & Exploration

[Objective] The plugging quality of cement plug in abandoned coalbed methane wells is critical to preventing pollutant leakage. Current standards for handling these wells involve simple mud pump injection, which often results in cement plugs with issues like particle agglomeration, bubbles, and micropores. These defects reduce the strength of the cement plug and compromise its sealing performance. [Methods] To address this, vibration technology is applied to the plugging operation, using a specialized tool to induce vibrations in the pipe string. This process enhances the fluidity of the cement slurry via the transmission of vibration energy, thereby improving the plugging quality …

Spatial Distribution And Influencing Factors Of Microseismic Events In Unequal-Length Mining Faces In Coal Mines, Zhou Jinyan, Yang Hongzeng, Gao Jietao

Coal Geology & Exploration

[Objective] The varying length of a mining face along its dip direction or adjusting mining significantly increases water inrush risks of the mining face. This study investigate the hazards and influencing factors brought by unequal length arrangements to the mining face is one of the key issues in deepening the research on coal mine water hazard prevention and ensuring the safe mining face. [Methods] With the No. 15240 mining face, consisting of a narrow part, a wide part, and a slope, in the Jiulong Coal Mine of the Jizhong Energy Fengfeng Group as the engineering background, a large amount of …

Development And Application Of A Supercritical Co2 Pulsed Fracturing-Seepage Coupling Test System, Liu Jiajia, Zhang Yunlong, Nie Zishuo, Gao Zhiyang, Xu Wensong

Coal Geology & Exploration

[Objective] To effectively enhance the extraction effects of coalbed methane (CBM), this study proposed a novel approach for fracturing coals (rocks) using pulsation of supercritical carbon dioxide (CO₂) by combining pulsed fracturing with supercritical CO₂ fracturing. [Methods] A true triaxial test system coupling supercritical CO₂ pulsed fracturing with seepage was independently developed, and its primary structure, characteristics, and functions were elucidated. Then, the supercritical CO₂ pulsed fracturing - seepage/acoustic emission monitoring tests under true triaxial conditions were conducted in the laboratory. The test system, controlling the triaxial stress by combining an independent servo system with …

Remote Sensing Monitoring And Spatiotemporal Characteristics Of Co2 And Ch4 Concentrations In Coal-Electricity Production Bases, Xu Yanfei, Chen Yongchun, Li Jing, Liu Xiaozhou, Miao Wei, Zhao Derong, Rui Chengqi

Coal Geology & Exploration

[Objective] CO₂ and CH₄ are identified as the primary greenhouse gases emitted from energy production in coal-electricity production bases. Mointoring these emissions and analyzing their spatiotemporal distribution are essential components of building a carbon monitoring system in the study area. [Methods] This study investigated Huainan City, Anhui Province as an example to explore the spatiotemporal characteristics of CO₂ and CH₄ in coal-electricity production bases. Specifically, this study examined the CO₂ and CH₄ concentrations in the study area based on data from the GOSAT，OCO-2, and Sentinel-5P satellites，determining the column concentration changes and distribution of CO …

Investigation And Comprehensive Utilization Of Resources In Closed Coal Mines In Anhui Province, China, Liu Feiyue, Chen Wanyun, Yang Ke, Duan Minke, Liu Qinjie, Yang Lingyue

Coal Geology & Exploration

[Objevtive] With the continuously intensive exploitation of coal resources and the structural reform of energy supply, many coal mines in Anhui Province have been closed due to resource depletion or backward production capacity. However, the closed coal mines still host resources such as underground spaces, residual coals, gas, mine water, land, and infrastructure equipment. Hence, reutilizing resources in closed coal mines holds significant engineering value and economic benefits. [Methods] Based on the general information and reutilization status of 59 coal mines in Anhui Province that have been closed since 2013, this study analyzed the distribution characteristics, residual resources, and reutilization …

Physical Simulation Experiments On Mining-Induced Water Inrushes From Coal Seam Floors: Advances In Research And Prospects, Zhang Pingsong, Ou Yuanchao

Coal Geology & Exploration

[Objective] Water inrushes from floors are subjected to the superimposed effects of factors such as specific geological structures, water-rock-stress coupling, and mining disturbance, proving complex, concealed, and abrupt. [Methods] Physical simulation experiments can effectively reproduce the environments of the floors and confined water, intuitively present the whole process of both mining-induced fracture propagation in the floors and the path evolution of water inrushes, and obtain multi-source data of all disaster stages in a real time manner. Therefore, such experiments enjoy unique advantages in investigating water inrushes from floors. [Results and Conclusions] This study reviews the research achievements in water inrushes …

A High-Resolution Method For Processing Coal Measures Seismic Data Based On Anisotropic Medium Theories And Its Application, Li Huiting, Chang Suoliang, Zhang Sheng, Guan Wenyuan, Zhao Xing, Wang Weiqian, Tantai Mingjun, Gao Kaixin

Coal Geology & Exploration

[Objective] The increasing importance of the exploration and exploitation of deep resources poses new requirements for high-precision seismic exploration. Given that conventional isotropy-based data processing methods are no longer applicable to the coal-bearing strata with strong anisotropy. [Methods] This study proposed a method for processing seismic data based on theories of both transverse isotropy medium with a vertical symmetry axis (VTI) media and transverse isotropy with a horizontal axis of symmetry (HTI) media. First, to characterize the depositional characteristics of coal-bearing strata, this study analyzed the features of VTI media, revealing that high-order dynamic correction can effectively eliminate anisotropy-induced event …

Study On Data Mining Of Hydrogen Energy Policy In China Based On Natural Language Processing Technology, Dongling Huang, Yuan Liu, Xiaoshuai Yuan, Guozhong Jin, Yuanhang Cai, Li Liu, Heng Cao, Wanjun Li, Rui Cai

Bulletin of Chinese Academy of Sciences (Chinese Version)

Report to the 20th National Congress of the CPC emphasized the importance of “working actively and prudently towards the goals of reaching peak carbon emissions and carbon neutrality”, as well as “speeding up the planning and development of a system for new energy sources”. As a green and low-carbon secondary energy source, hydrogen energy has multiple applications in promoting the large-scale and efficient use of renewable energy as well as energy substitution in the field of transportation. It can also accelerate decarbonization in industry, and as such, is an indispensable part of building a new energy system, reaching peak carbon …

Modified Method For Assessing The Required Expenditures And Estimated Time Of Hard Coal Mine Liquidation, Andrzej Chmiela, Małgorzata Wysocka, Adam Smoliński

Journal of Sustainable Mining

The restructuring of hard coal mining requires significant budgetary expenditures. A comprehensive scientific approach may facilitate the rationalisation and minimisation of mine closure costs. This study proposes a method for the preliminary estimation of the costs and time required for the potential liquidation of a hard coal mine. In addition to a literature review, a statistical analysis and a case study, personal interviews were conducted with individuals with direct management over the restructuring, reclamation and liquidation processes pertaining to mines undergoing closure.

The assessment method is based on an analysis of the mine liquidation costs, divided into successive years of …

Embodied Urban Political Ecology Of Oil: Social Reproduction In Oil ‎Geographies Case Study: Ahwaz, Khuzestan, Iran, Maryam Amiri

Dissertations and Theses

This dissertation examines the transformative impact of the oil industry on social ‎reproduction ‎‎within the urban and ecological landscapes of Khuzestan Province, Iran, and ‎its center, the city ‎of Ahwaz. Specifically, the study sought to understand the effects of ‎the oil industry on social ‎reproduction in three key areas: gender relations, race/ethnic ‎relations, and daily life ‎amidst ‎environmental pollution caused by the oil industry.

‎This is explored through three sub-questions: 1) How are hierarchical socio-‎spatial ‎relationships perpetuated through practices of ‎everyday life? 2) How are gender ‎relationships redefined and ‎reproduced in the oil city? 3) How ‎are ethnic relationships ‎redefined …

Study On Law And Influencing Factors Of Air Leakage In Isolated Island Working Face With Large Burial Depth, Gang Wang, Mingze Xia, Shuliang Xie, Hao Xu, Shuxin Wang, Xintai Deng

Journal of Sustainable Mining

During the mining of a single coal seam isolated island work surface with large burial depth, the high mine pressures can crush and break the protective coal pillars, causing serious air leakages in the rear goaf. Herein, we use the analytic hierarchy process(AHP) to determine the main influencing factors of air leakage in island mining face. The air leakage source and sink in goaf were determined by measuring the differential pressures between the island mining face and the adjacent goaf using the energy level measurement method. The air volumes in the roadways were monitored on site to quantitatively analyze the …