Article
Thermodynamics
Lijun Zhou, Xihua Zhou, Chaojun Fan, Gang Bai
Summary: Injection of gas mixture into coal seam enhances methane recovery and reduces CO2 emission. The permeability of coal is affected by injected pressure, temperature, and CO2 component. Simulation results show that the continuous injection of gas mixture replaces and drives methane towards the extraction borehole. The coal permeability is influenced by heat or gas sorption-induced coal swelling/shrinkage, gas pressure, geostress-induced deformation, and coal mechanical properties.
Article
Thermodynamics
Yujie Li, Cheng Zhai, Jizhao Xu, Yong Sun, Xu Yu
Summary: This study investigates the feasibility of enhanced coalbed methane (CBM) recovery through steam injection. Results show that steam injection can increase the internal temperature of coal samples and induce thermal cracking, facilitating gas desorption and migration. Furthermore, steam preferentially condenses in coal micropores and has the potential to displace methane. The study suggests that steam injection may not cause water blocking effects. These findings provide valuable insights for the field application of steam injection to enhance CBM production.
Article
Engineering, Environmental
Gaoming Wei, Hu Wen, Jun Deng, Zhenbao Li, Shixing Fan, Changkui Lei, Mingyang Liu, Lifeng Ren
Summary: The study utilizes hydraulic slotting and liquid CO2 injection to enhance coalbed permeability and methane recovery efficiency. The results show a significant increase in coal porosity and permeability, leading to more than 90% CBM recovery efficiency. The in-situ test indicates effective radii for HS and LCO2 injection were 2.5 m and 10 m, respectively, with a 2.2-fold increase in CBM recovery efficiency.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2021)
Article
Engineering, Environmental
Erlei Su, Yunpei Liang, Quanle Zou, Minghan Xu, Agus P. Sasmito
Summary: The study focused on the evolution of permeability during coalbed methane extraction, observing the influence of initial gas pressure, diffusion coefficient, and permeability on permeability rebound and recovery. The results showed that higher initial gas pressure led to longer rebound and recovery times, while initial diffusion coefficient and permeability had a negative impact on these parameters.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2021)
Article
Thermodynamics
Gang Bai, Jun Su, Xueming Li, Chunsheng Guo, Mingxu Han, Xihua Zhou, Chaojun Fan
Summary: The study proposes an SBS-CO2 method that gradually increases the CO2 injection pressure, which can improve the total recovery rate of methane and reduce the risk of CO2 consumption and outburst compared to the traditional constant CO2 injection pressure method.
Article
Energy & Fuels
Yifu Han, Kailei Liu
Summary: Core-scale laboratory experiments on rock samples are commonly used to evaluate the efficiency of potential chemical EOR agents, but insufficient sample quantities and inability to restore core plugs to their initial state can lead to biased evaluations. To address this issue, constructing a digital rock and conducting numerical simulations can help mitigate uncertainties. In this study, an integrated digital rock construction workflow is proposed to upscale pore-scale simulation results to core-scale rock physics models, improving accuracy and practicality in routine analysis and modeling.
Article
Computer Science, Interdisciplinary Applications
Long Cheng, Zhifeng Luo, Yaozeng Xie, Liqiang Zhao, Lin Wu
Summary: In this paper, a thermo-hydro-mechanical-damage coupled model is proposed to study the mechanism of thermo-hydro-mechanical-damage behaviors during enhanced oil recovery. The model considers the thermo-poroelastic deformation, two-phase flow, and heat transport within a finite element framework. Rock damage is determined by failure criterions, and the contact problem for pre-existing fractures is solved using the extended finite element method and augmented Lagrangian multipliers method. Numerical simulations demonstrate the evolution of damage, fracture activation, and enhanced permeability caused by the thermoporoelastic response during water injection. The study shows that comprehensive modeling of thermo-hydro-mechanism-damage behaviors is important for enhanced oil recovery and other underground liquid injection engineerings.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Energy & Fuels
Yi Chen, Lei Zhou, Yu Peng, Xiangyan Ren
Summary: This study investigates the potential of directional wells with multiple hydraulic slots as a stimulation technology for deep coalbed methane extraction. The research finds that hydraulic slotting increases permeability and gas desorption, and directional wells with multiple slots optimize performance and enhance CBM recovery.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2023)
Article
Chemistry, Multidisciplinary
Bo Li, Junxiang Zhang, Zhiben Ding, Bo Wang, Peng Li
Summary: This study suggests that ECBM recovery by N-2 injection is a feasible technical method for low-permeability coal reservoirs. The research found that coal permeability increases gradually and finally stabilizes during the N-2 injection process. The proposed dynamic evolution model of coal permeability can be applied to predict CBM production and guide engineering applications.
Article
Thermodynamics
Draco Iyi, Yakubu Balogun, Babs Oyeneyin, Nadimul Faisal
Summary: This study quantitatively explores the influence of injection rate and temperature on oil-water relative permeability curves during hot water flooding operations. It demonstrates that the relative permeability of oil is strongly influenced by flow, while the effect of the relative permeability of water is negligible. Additionally, the flow rate affects the residual oil and water saturation, as well as the associated effective permeability.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Green & Sustainable Science & Technology
Peng Zhao, Jun Liu, Derek Elsworth
Summary: This study investigates an enhanced geothermal system (EGS) reservoir with horizontal wells and multiple hydraulic fractures, focusing on the effects of complex thermal-hydraulic-mechanical interactions on the thermal unloading of rock matrix and permeability evolution. The proposed model is validated against existing analytical solutions and a demonstration project, and the impact of fracture number on heat extraction is discussed. Results show that thermal unloading-induced matrix permeability enhancement should be considered in the coupled model, as it greatly affects the maximum temperature difference and the cooling range along the production well. Generally, more fractures in the EGS lead to higher production temperatures. The fracture number plays a crucial role in considering the heat transportation rate and the cooling range in geothermal exploration, with only slight differences in heat extraction ratio between numerical cases considering both matrix and fracture geothermal exploitation.
Article
Chemistry, Physical
D. V. Guzei, S. V. Ivanova, A. V. Minakov, M. I. Pryazhnikov
Summary: The use of nanofluid for sequential injection can greatly improve oil recovery efficiency while reducing the amount of nanoparticles used.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Multidisciplinary
Lin Zhang, Chengmin Wei, Yao Nie, Ruiying Wang
Summary: The research on active nitrogen injection pressure measurement is of great significance to improve pressure measurement efficiency. Experimental results show that when the injected nitrogen pressure is close to the original coal seam gas pressure, the borehole gas pressure balance time is shorter. A numerical solver for active pressure measurement was developed based on OpenFOAM and C++ language.
Article
Engineering, Aerospace
Dai Jian, Zuo Qiuru, Huang Chao
Summary: The study found that the grooved configuration significantly improves supersonic mixing in the scramjet combustor, enhancing fuel uniformity in the downstream region.
Article
Energy & Fuels
Moataz Mansi, Mohamed Almobarak, Christopher Lagat, Quan Xie
Summary: Development of shale gas reservoirs is the fastest growing area due to potential reserves. CO2 injection into shale reservoirs initiates enhanced gas recovery and CO2 sequestration, but there are uncertainties due to heterogeneity and complexity. This study aims to provide a practical screening tool to manage and predict the efficiency of enhanced gas recovery and CO2 sequestration in shale reservoirs.
Article
Chemistry, Physical
Yi Xue, Jia Liu, Xin Liang, Xue Li, Songhe Wang, Zongyuan Ma, Shaowei Zhang, Xuanye Jiao
Summary: As the simplest saturated hydrocarbon, methane plays a crucial role in hydrogen and carbon energy. Maintaining the stability and sealing of caprock is essential for safe underground storage of energy. A fully coupled two-phase flow model is established to study the migration mechanism of methane in caprock, considering the characteristics of the dual porosity medium. The model incorporates methane and brine seepage in the fracture network and the dynamic adsorption-desorption process in the matrix.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Geological
Yi Xue, P. G. Ranjith, Feng Gao, Zhizhen Zhang, Songhe Wang
Summary: The mechanical behavior of coal under different gas pressures was investigated in this study. The influence of gas pressure on the mechanical properties of coal and the energy input and dissipation during loading were analyzed. The effects of gas pressure on coal strength were also theoretically analyzed. The results show that the absorbed energy in the axial pressure direction accounts for the main proportion of the total absorbed energy by coal.
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2023)
Article
Thermodynamics
Jia Liu, Yi Xue, Yong Fu, Kai Yao, Jianqiang Liu
Summary: Technical advances in horizontal drilling and hydraulic fracturing have improved shale gas development, but sustainability is a challenge. Microwave irradiation can be used as an auxiliary technology for hydraulic fracturing to promote sustainable development. This study developed a fully coupled model to investigate the multiphysics coupling mechanisms and optimize recovery schemes for shale gas. The proposed model provides theoretical guidance for the field application of microwave-thermal recovery of shale gas.
Article
Energy & Fuels
Yi Xue, P. G. Ranjith, Yang Chen, Chengzheng Cai, Feng Gao, Xingguang Liu
Summary: Geological sequestration of CO2 is important for reducing global warming and achieving carbon neutralization. This study evaluates the effect of CO2 adsorption pressure on the mechanical properties of coal mass using experimental and analytical methods. An elastic damage model is established to describe the nonlinear stress-strain relationship of coal under CO2 adsorption. The results show that increasing adsorption pressure increases the risk of coal damage and fracturing, leading to a more complex fracturing process.
Article
Engineering, Civil
Huimin Wang, Qing Zhou, Jinchang Sheng, Yulong Luo, Jia Liu, Xingxing Liu
Summary: Investigating the evolution of porosity and permeability in carbonate rocks during long-term infiltration is a challenging problem in rock engineering. The complex pore structures in carbonate rocks include various types of pores and fractures. In this study, a rock seepage coupled nuclear magnetic resonance (NMR) online analysis and imaging system platform was used to quantify the variation in pore volume at different scales. The results showed that the permeability-porosity evolution can be divided into three stages based on the experimental data and permeability measurements.
JOURNAL OF HYDROLOGY
(2023)
Article
Energy & Fuels
Shengcheng Wang, Shanjie Su, Dengke Wang, Peng Hou, Yi Xue, Xin Liang, Chengzheng Cai, Xianghe Gao, Yuhao Jin, Shuo Yang, Xuan Jiang
Summary: Liquid nitrogen fracturing is expected to be an effective method for increasing coalbed methane production due to its good reservoir adaptability. The advantages of ultra-low temperature and high gasification pressure during the fracturing process need further exploration.
GEOMECHANICS FOR ENERGY AND THE ENVIRONMENT
(2023)
Article
Energy & Fuels
Yi Xue, Shuai Liu, Junrui Chai, Jia Liu, P. G. Ranjith, Chengzheng Cai, Feng Gao, Xue Bai
Summary: Deep geothermal energy exploitation involves using an enhanced geothermal system (EGS) to extract heat from hot dry rock (HDR) through hydraulic fracturing technology. A thermal-hydraulic-mechanical coupling model is proposed to study the effects of water-cooling shock on fracture initiation and morphology in HDR hydraulic fracturing. The results show that water-cooling shock can significantly reduce fracture initiation pressure, induce more secondary fractures, and form complex fracture networks, with initial rock temperature and heat transfer coefficient affecting fracture morphology.
Article
Geochemistry & Geophysics
Linchao Wang, Yi Xue, Xuyang Shi, Zhihao Zhang, Xue Li, Lin Zhu, Ruifu Liu, Lin Sun, Caifang Wu, Songbao Feng, Yu Wang
Summary: The utilization of liquid nitrogen as a sustainable and water-free fracturing medium shows great promise in engineering applications. This study investigates the impact of liquid nitrogen cooling on the internal structure and mechanical properties of rocks using Brazilian split tests and acoustic emission tests. The findings reveal that high-temperature liquid nitrogen treatment significantly modifies the microscopic structure and mechanical properties of rocks, potentially affecting their overall stability and reliability.
Article
Environmental Sciences
Linchao Wang, Yi Xue, Zhengzheng Cao, Hailing Kong, Jianyong Han, Zhizhen Zhang
Summary: Liquid nitrogen fracturing is an important technique for the development of geothermal energy, promoting fracture formation and heat exchange in hot dry rocks. The study shows that cycling cooling with liquid nitrogen leads to a decrease in rock strength, an increase in energy release, and surface roughness of granite, thus promoting the formation of internal fractures.
Review
Materials Science, Multidisciplinary
Lin Zhu, Weihua Ding, Faning Dang, Guochen Sang, Yi Xue, Qiaoyu Wang
Summary: This paper investigates the thermal conductivity and pore characteristics of lightweight aggregate concrete (LWAC) with microencapsulated phase change materials (MPCM). Experimental and theoretical investigations reveal a clear relationship between pore characteristics and MPCM dosage. An improved theoretical model is proposed to consider the impact of pore characteristics on the effective thermal conductivity (ETC) of MPCM-LWAC. The experimental and theoretical results demonstrate the effectiveness of the improved model in predicting the ETC of MPCM-LWAC.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Multidisciplinary Sciences
Jia Liu, Yi Xue, Xin Liang, Songhe Wang
Summary: A particle-tracing method is proposed to investigate proppant reflux phenomena in hydraulically induced fractures during fracturing fluid flowback. The study explores the effects of fracture roughness on proppant particle migration.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2023)
Article
Green & Sustainable Science & Technology
Lars odegaard Bentsen, Narada Dilp Warakagoda, Roy Stenbro, Paal Engelstad
Summary: This study investigates uncertainty modeling in wind power forecasting using different parametric and non-parametric methods. Johnson's SU distribution is found to outperform Gaussian distributions in predicting wind power. This research contributes to the literature by introducing Johnson's SU distribution as a candidate for probabilistic wind forecasting.
JOURNAL OF CLEANER PRODUCTION
(2024)
Article
Green & Sustainable Science & Technology
Xing Liu, Qiuchen Wang, Yunhao Wen, Long Li, Xinfang Zhang, Yi Wang
Summary: This study analyzes the characteristics of process parameters in three lean gas ethane recovery processes and establishes a prediction and multiobjective optimization model for ethane recovery and system energy consumption. A new method for comparing ethane recovery processes for lean gas is proposed, and the addition of extra coolers improves the ethane recovery. The support vector regression model based on grey wolf optimization demonstrates the highest prediction accuracy, and the multiobjective multiverse optimization algorithm shows the best optimization performance and diversity in the solutions.
JOURNAL OF CLEANER PRODUCTION
(2024)
Article
Green & Sustainable Science & Technology
Cairong Song, Haidong Yang, Xian-Bing Meng, Pan Yang, Jianyang Cai, Hao Bao, Kangkang Xu
Summary: The paper proposes a novel deep learning-based prediction framework, aTCN-LSTM, for accurate cooling load predictions. The framework utilizes a gate-controlled multi-head temporal convolutional network and a sparse probabilistic self-attention mechanism with a bidirectional long short-term memory network to capture both temporal and long-term dependencies in the cooling load sequences. Experimental results demonstrate the effectiveness and superiority of the proposed method, which can serve as an effective guide for HVAC chiller scheduling and demand management initiatives.
JOURNAL OF CLEANER PRODUCTION
(2024)
Article
Green & Sustainable Science & Technology
Zhe Chen, Xiaojing Li, Xianli Xia, Jizhou Zhang
Summary: This study uses survey data from the Loess Plateau in China to evaluate the impact of social interaction on the adoption of soil and water conservation (SWC) technology by farmers. The study finds that social interaction increases the likelihood of farmers adopting SWC, and internet use moderates this effect. The positive impact of social interaction on SWC adoption is more pronounced for farmers in larger villages and those who join cooperative societies.
JOURNAL OF CLEANER PRODUCTION
(2024)
Article
Green & Sustainable Science & Technology
Chenghua Zhang, Yunfei Yan, Kaiming Shen, Zongguo Xue, Jingxiang You, Yonghong Wu, Ziqiang He
Summary: This paper reports a novel method that significantly improves combustion performance, including heat transfer enhancement under steady-state conditions and adaptive stable flame regulation under velocity sudden increase.
JOURNAL OF CLEANER PRODUCTION
(2024)
