Article
Geosciences, Multidisciplinary
Tengfei Cao, Zhaobiao Yang, Yong Qin, Zhiming Yan, Zhaoying Chen, Chao Li
Summary: The study analyzed the vertical distribution characteristics of modern in situ stress and its impact on permeability in the Yangquan mining area based on injection pressure drop test data and acoustic emission test data. The results indicated different stress zones within burial depths, corresponding to variations in permeability. The study also explored the exploitation of the No. 15 coal reservoir and found that the permeability was influenced by various stress factors.
NATURAL RESOURCES RESEARCH
(2021)
Article
Energy & Fuels
Chuanqi Tao, Yong Li, Yanbin Wang, Xiaoming Ni, Xiang Wu, Shihu Zhao
Summary: Deep coalbed methane (CBM) has great exploration and development potential, but its commercial development worldwide is limited. The Linxing area, with coals buried approximately 2000m deep, shows significant development potential. Factors controlling deep CBM accumulation, such as reservoir temperature and pressure, coal composition, and gas content, were analyzed.
Article
Environmental Sciences
Xiaoming Ni, Xuebin Tan, Sen Yang, Bin Xu, Xiaokang Fu
Summary: The evaluation of CBM production potential considering different coal structures can better reflect the objective facts, especially in areas with strong heterogeneity in coal structure. The proposed method provides a novel approach to accurately evaluate CBM production potential in regions with highly heterogeneous coal structures.
ENVIRONMENTAL EARTH SCIENCES
(2021)
Review
Energy & Fuels
Wancheng Zhu, Shuyuan Liu, Xiufeng Zhang, Chenhui Wei
Summary: This paper provides a comprehensive review of the mechanisms and properties of gas adsorption in coal, the geomechanical behavior of coal, and the mechanisms of gas transport in coal. It also discusses several waterless fracturing techniques for improving coalbed permeability and identifies current knowledge and research gaps.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2022)
Article
Microbiology
Mansi Chawla, Meeta Lavania, Nishi Sahu, Sudhanshu Shekhar, Nimmi Singh, Anand More, Magesh Iyer, Sanjay Kumar, Komal Singh, Banwari Lal
Summary: It is acknowledged that conventional mining techniques have resulted in depleting coal reserves globally. A sustainable approach to improve coalbed methane (CBM) recovery involves enhancing biogenic methane production through microbial stimulation. In this study, a culture-independent approach was used to investigate the microbial community in an Indian reservoir, and it was found that bacteria were more abundant than archaea. The dominant phyla were Proteobacteria, Firmicutes, and Bacteroidetes, which play crucial roles in methanogenesis.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Environmental Sciences
Xiao Feng, Panpan Zhang, Zizhong Zhang, Hongguang Guo, Zhigang Li, Zaixing Huang, Michael Urynowicz, Muhammad Ishtiaq Ali
Summary: Biomethane generation by coal degradation can increase coalbed methane (CBM) reserves and affect the pore structure of coal. The biodegradation of bituminous coal and lignite to produce methane was performed to analyze the effect on coal pore development. The results showed that biodegradation decreased the specific surface area and pore volume of micropores and increased the fractal dimension. Various organics were generated, with a portion released into the culture solution and the majority remaining in residual coal. The effect of biodegradation on pore development depended on the combined action of methane production and organics retention in coal.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Engineering, Environmental
Devi Prasad Mishra, Suraj Kumar Verma, Ram Madhab Bhattacharjee, Rajeev Upadhyay, Patitapaban Sahu
Summary: This study comprehensively assesses the geological and microstructural characteristics of two gassy coal seams in the Moonidih colliery. It found that the XV seam is more suitable for methane drainage due to its favorable properties.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2023)
Article
Geosciences, Multidisciplinary
Qixian Li, Jiang Xu, Shoujian Peng, Fazhi Yan, Bin Zhou, Ende Han, Cheng Jiang
Summary: Coalbed methane co-production technique was explored in this study, revealing the pressure equilibrium and gas flow between different coal reservoirs. The study further demonstrated the dynamic supply state in coalbed methane production, enabling effective management and optimization of production efficiency.
NATURAL RESOURCES RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Yanlei Guo, Haibin Liu, Xu Zhou, Jian Chen, Liwen Guo
Summary: The XGBoost-GR-stacking gas outburst early warning model proposed in this article demonstrates high accuracy and practical performance, making it suitable for gas outburst risk warning in mining safety. The model is based on gas outburst data from 26 mines and establishes a data generation model based on XGBoost. Grey correlation analysis is used to select the main control factor groups based on the sorting of correlation degrees. Comparing the actual and predicted values for each model, the stacking fusion model achieves the highest accuracy in gas outburst prediction and the best model fitting effect.
APPLIED SCIENCES-BASEL
(2023)
Article
Mechanics
Zheng Shang, Haifeng Wang, Bing Li, Yuanping Cheng, Xinghua Zhang, Fei Zhao, Xiao Zhang, Congmeng Hao, Zhenyang Wang
Summary: The research findings indicate that in liquid carbon dioxide phase-transition blasting, the release pressure plays a decisive role in the generation of fractures in terms of quantity and direction. Increase in confining pressure stress decreases expansion of boreholes and fracture zones, but does not affect the number and direction of blast cracks.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Engineering, Geological
Shirong Cao, Zhaolong Ge, Di Zhang, Zhe Zhou, Yiyu Lu, Hanyun Zhao
Summary: This study investigates the rock-breaking mechanism and pore structure evolution of typical reservoir rocks under ultra-high pressure water jet (UHP-WJ) impingement. The results show that different types of rocks exhibit different fracture mechanisms and pore structure evolutions under UHP-WJ impact. These findings provide important theoretical references for optimizing the development of unconventional natural gas reservoirs.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Energy & Fuels
Tiantian Zhao, Hao Xu, Dazhen Tang, Peng Zong
Summary: This study conducted unsteady displacement experiments using coal samples based on nuclear magnetic resonance technology to monitor the interface effect between gas and water, establishing and verifying a new relative permeability model that considers the interface effect. The results show that in two-phase flow, the interface effect plays a dominant role, with the gas phase driving the water phase, resulting in a relative permeability of the water phase greater than 1.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2021)
Article
Energy & Fuels
Hui Wang, Yanbin Yao, Dameng Liu, Yidong Cai, Yanhui Yang, Shengqiang Zhou
Summary: This study proposes a well logging coal structure index (WCSI) to quantify coal deformation and its impact on coalbed methane productivity. The results show that the degree of coal seam deformation affects reservoir permeability and hydraulic fracturing effectiveness, subsequently influencing gas production rate. The WCSI is found to be a useful parameter for preliminary forecasting of gas production in the southern Qinshui Basin.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Microbiology
Yang Li, Jian Chen, Shuheng Tang, Zhaodong Xi
Summary: The rise of coalbed methane bioengineering allows for the conversion and utilization of carbon dioxide through microbial action and the carbon cycle. Hydraulic fracturing improves the natural permeability of tight reservoirs, enhances the living conditions of microbial communities, and strengthens the carbon circulation process in coal reservoirs.
Article
Engineering, Geological
Shuai Chen, Linming Dou, Wu Cai, Lei Zhang, Miaomiao Tian, Zepeng Han
Summary: Coalbed methane (CBM) is an important unconventional fuel source, and its efficient extraction is crucial for reducing greenhouse gas emissions and ensuring coal mine safety. This study utilized micro-computed tomography and deep learning to analyze the behavior of coal fractures under liquid nitrogen cyclic fracturing. The results showed that LN2 treatment can effectively damage the coal sample and promote fracture expansion. The study provides insights into the application of LN2 cyclic fracturing in CBM recovery.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)