Review
Green & Sustainable Science & Technology
Zhennan Zhu, Shengqi Yang, Pathegama Gamage Ranjith, Wenling Tian, Hong Tian, Jun Zheng, Guosheng Jiang, Bin Dou
Summary: This research analyzed and determined the changes in the mechanical characteristics of granites after various thermal shocks through a comprehensive review of research. The change mechanisms of the mechanical responses of granites after various thermal shocks were revealed by microstructural observations. The macroscale deterioration of the mechanical parameters of various granites after thermal shocks is closely associated with the initiation, development, and coalescence of microcracks.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Energy & Fuels
Pan Li, Yang Hao, Yu Wu, Ayal Wanniarachchi, Hongxue Zhang, Zhili Cui
Summary: This study simulated CO2 storage and heat extraction in fractured granite by alternating injection of water and supercritical CO2. It was found that increasing the non-contact area and CO2 flow velocity can prevent a large decrease in reservoir permeability, leading to increased heat extraction and CO2 mineralization storage.
Article
Geochemistry & Geophysics
Xiaoqi Ye, Ziwang Yu, Yanjun Zhang, Jianguo Kang, Shaohua Wu, Tianrui Yang, Ping Gao
Summary: Accurate estimation of thermal conductivity of rocks is crucial for various projects, and this study focuses on testing 30 granite samples from China. Different mineral contents determine the overall thermal conductivity of rocks. Existing models have limitations, but a new model combining two existing models is proposed, which provides more accurate and universally applicable estimations. Mineral composition significantly improves the accuracy of thermal conductivity calculation.
Article
Green & Sustainable Science & Technology
Bailong Liu, Anna Suzuki, Noriaki Watanabe, Takuya Ishibashi, Kiyotoshi Sakaguchi, Takatoshi Ito
Summary: Simulation experiments show that the complex fracture network formed by supercritical water fracturing in rock can effectively increase permeability, improve heat exchange surface area, and play a significant role in geothermal resource development.
Article
Green & Sustainable Science & Technology
Biao Shu, Junjie Chen, Hui Xue
Summary: This paper investigates the impact of fluid-rock interaction on the pore structure and strength of granite in different zones of CO2-EGS through experiments conducted at 240°C and 37 MPa. The results show that water/ScCO2 dissolves albite and potassium feldspar in granite and carbon in ScCO2 may be sequestered in the form of carbonate mineral precipitates. The injection of ScCO2 fluids increases the pore volume of the rock. Only with sufficient water, the ScCO2 fluid can significantly change the strength and elastic modulus of the rock sample.
Article
Green & Sustainable Science & Technology
Petri Hakala, Sami Vallin, Teppo Arola, Ilkka Martinkauppi
Summary: This study utilized the Enhanced Thermal Response Test (ETRT) to investigate the thermal conductivity, natural convection, and thermal resistance of deep bedrock, presenting a novel approach to enhance accuracy.
Article
Geosciences, Multidisciplinary
M. Rajaobelison, J. Raymond, M. Malo, C. Dezayes, S. Larmagnat
Summary: The study improves geothermal exploration concepts by assessing the petrophysical rock properties of samples from surface outcrops, providing fundamental knowledge on thermohydraulic rock properties to help identify heat transfer mechanisms associated with geothermal resources. The geology of the two areas is mainly Quaternary volcanics and Permian-Triassic sediments, with normal faults related to extensional regime characteristics.
NATURAL RESOURCES RESEARCH
(2021)
Article
Engineering, Geological
Huan Li, Zhongwei Huang, Jingbin Li, Xiaojing Li, Tianwen Jiang, Jianxiang Chen
Summary: The swirling impeller abrasive water jet (SAWJ) was investigated as an alternative jet type for drilling laterals in the hot dry rock (HDR) reservoirs. The SAWJ was found to efficiently create large and regular holes in hard granite, improving the rock-breaking performance compared to the swirling impeller water jet (SWJ) technique.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Mining & Mineral Processing
Jianjun Hu, Heping Xie, Qiang Sun, Cunbao Li, Guikang Liu
Summary: This study conducted thermal damage tests on granite at different temperatures and quenching cycles to reveal the impact of thermal fatigue damage on hot dry rock. Results showed that increasing temperature and cycles led to crack development in granite, reducing its properties. The research also established a nonlinear relationship among thermal conductivity, temperature, and cycle number for hot dry rock, providing theoretical support for reservoir reconstruction and production efficiency evaluation.
INTERNATIONAL JOURNAL OF MINING SCIENCE AND TECHNOLOGY
(2021)
Article
Thermodynamics
Jie Zhang, Meng Zhao, Guiyang Wang, Peifa Ma
Summary: The study focused on the heat extraction efficiency of four injection wells and one production well, finding that increasing injection temperature and injection-production distance can improve thermal extraction rate. The three-injection and one-production well pattern demonstrates better heat extraction performance for heating demand.
APPLIED THERMAL ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Baiyi Li, Jixiong Zhang, Hao Yan, Nan Zhou, Meng Li
Summary: This article investigates the thermal conductivity of gangue-cemented paste backfill through laboratory tests and analyzes the influences of mix proportion parameters and water saturation degree. The results show that the water/binder ratio significantly affects the thermal conductivity, while the cement amount has little influence. Moreover, there is a linear positive correlation between thermal conductivity and water saturation degree.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Multidisciplinary Sciences
Meiling Zhou, Jianlin Li, Zuosen Luo, Jianbin Sun, Feng Xu, Qiao Jiang, Huafeng Deng
Summary: The study found that water-rock interaction leads to an increase in pore size, an initial increase and subsequent decrease in the number of pores, a change in pore shape from oblate to slender, as well as variations in shape factor and fractal dimension. The results provide insights into the damage of rock mesostructure under water-rock interaction.
SCIENTIFIC REPORTS
(2021)
Article
Green & Sustainable Science & Technology
Yu Wu, Pan Li, Yang Hao, Ayal Wanniarachchi, Yan Zhang, Shuhua Peng
Summary: The study investigated the heat extraction and CO2 storage in hot dry rock using CO2-EGS technology through a series of experiments. The findings revealed the mechanism of CO2 storage and its potential applications in the future.
Article
Engineering, Chemical
Yuchao Zeng, Fangdi Sun, Haizhen Zhai
Summary: The vertical permeability heterogeneity in stratified formations significantly influences the electricity generation performance of enhanced geothermal systems, affecting water production rate, electric power, reservoir impedance, and pump power. However, vertical permeability heterogeneity is not the main factor affecting injection pressure and energy efficiency in the system.
Article
Energy & Fuels
Ning Li, Tong Zhou, Mengyun Zhao, Haibo Wang, Xiaodong Hu, Yushi Zou, Zhaopeng Zhang
Summary: The study shows that increasing thermal treatment temperature leads to a decrease in hardness and Young's modulus of fracture surface, affecting fracture conductivity. For propped fractures, higher thermal treatment temperature results in lower fracture conductivity, while for self-propped fractures, the thermal shock effect may enhance or reduce conductivity.
Article
Engineering, Geological
Wang Zhang, Ben-lin Xiao, Da-wei Hu, Hui Zhou, Jun Zheng, Fan Zhang
Summary: This study analyzed the effects of sulfate attack on the permeability, ultrasonic P-wave velocity, uniaxial compression, and splitting tensile strength of cement mortar specimens using geotechnical testing methods. The results showed that the gas permeability, ultrasonic P-wave velocity, and mechanical properties of the specimens changed under different confining pressure conditions. Sulfate attack increased the gas permeability, decreased the ultrasonic P-wave velocity, and reduced the tensile and compressive strength of the specimens.
ENVIRONMENTAL GEOTECHNICS
(2022)
Article
Engineering, Geological
Changdong Ding, Yang Zhang, Dawei Hu, Hui Zhou, Jianfu Shao
ROCK MECHANICS AND ROCK ENGINEERING
(2020)
Article
Geochemistry & Geophysics
Fan Zhang, Tao He, JunjieKang, Dawei Hu
Summary: This study investigated the effect of chemical corrosion on the strength and damage characteristics of granite specimens with fissures. The results showed that as the time of chemical corrosion increased, the peak strength and elastic modulus of the specimens decreased significantly, especially for those with a fissure angle of 45 degrees.
Article
Construction & Building Technology
Zhipeng Yu, Fan Zhang, Xiao Ma, Fujian Yang, Dawei Hu, Hui Zhou
Summary: The study investigated the thermal expansion behavior of concrete under three-dimensional stress using a high-temperature true triaxial test system. It found that the thermal expansion strain of concrete under such stress state undergoes increasing and stabilizing stages, and the stress has a significant restraint on the thermal expansion of concrete. Additionally, the average coefficient of thermal expansion of concrete under different temperatures was calculated, demonstrating the impact of stress on concrete's thermal expansion characteristics.
ADVANCES IN CIVIL ENGINEERING
(2021)
Correction
Engineering, Geological
Changdong Ding, Yang Zhang, Dawei Hu, Hui Zhou, Jianfu Shao
Summary: A correction to the paper has been published and the authors have provided a link to the correction.
ROCK MECHANICS AND ROCK ENGINEERING
(2021)
Article
Engineering, Geological
Hongliang Tu, Hui Zhou, Yang Gao, Jingjing Lu, Hemant Kumar Singh, Chuanqing Zhang, Dawei Hu, Mingming Hu
Summary: The study conducted a probability analysis of deep-buried diversion tunnels using Monte Carlo simulation, with a case study of the Jinping II hydropower station diversion tunnels. The results showed that the vertical load and radial subgrade modulus are important factors affecting the safety of tunnel support structures.
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2021)
Article
Energy & Fuels
Dongdong Ma, Changkun Cheng, Changdong Ding, Jinliang Song, Dawei Hu, Hui Zhou
Summary: The study compared liquid CO2 and water fracturing on tight sandstone and found that liquid CO2 fracturing can significantly reduce breakdown pressure, generate more micro-scale cracks, and result in more tortuous fracture plane compared to water fracturing.
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2021)
Article
Geochemistry & Geophysics
Yang Zhang, Jinliang Song, Dawei Hu, Yuzhang Liu, Fujian Zhou
Summary: This study investigates the effect of different roughnesses and high normal stresses on shear behaviors of rock joints. Replicas of natural rock joint surfaces were constructed and direct shear tests were performed. The results show that shear strength dependence on surface roughness is similar at different normal stresses, and the JRC-JCS criterion can describe the peak shear strengths accurately. The shearing mechanism of joints with different JRC values is asperity shearing off.
Article
Engineering, Geological
Jinliang Song, Degui Xiang, Dawei Hu, Hui Zhou, Dongdong Guo, Guoping Zhang
Summary: This paper presents an experimental study on the creep characteristics of a shale softened by THMC treatments. The results show that the creep rate of the softened zones increases, while the Young's modulus and hardness decrease. These findings help to understand the creep deformation mechanism and proppant embedment in fractured shales.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Engineering, Geological
Zhiyao Cheng, Zhaowei Chen, Wenbao Dong, Dawei Hu, Hui Zhou
Summary: Fractures in rock masses have a significant impact on the hydromechanical behaviors of rocks. This study developed a method to determine the equivalent effective stress coefficient of rocks with a single fracture and analyzed the effects of fracture filling area ratio, confining stress, and pore pressure. The results show that the equivalent effective stress coefficient increases with decreasing filling area ratio or confining stress, and increasing pore pressure.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Engineering, Geological
Xiao Ma, Wenbao Dong, Dawei Hu, Hui Zhou
Summary: In this study, true triaxial compression tests were conducted on granite specimens at different temperatures and under different intermediate principal stresses. The influences of temperature on crack initiation stress, crack damage stress, and peak strength of granite were analyzed. The failure characteristics of granite specimens under high temperature and true triaxial stress were investigated, and a Mogi-Coulomb failure criterion with temperature-dependent coefficients was proposed. This study provides new insights into the mechanical properties of rock under high temperature and true triaxial compression.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2023)
Article
Engineering, Geological
Bolun Zhang, Fujian Yang, Dawei Hu, Hui Zhou
Summary: It is widely acknowledged that underground fluid injection activities can induce earthquakes, which greatly affects the exploitation of underlying resources. This study focused on the effects of fault properties on injection-induced fault activation and shear slip behavior using sandstone samples with different levels of roughness. The findings indicate that rough fractures exhibit dilatancy followed by shear slip, while smooth fractures experience simultaneous dilatancy and shear slip. Fractures of all roughness levels experience varying degrees of abrasion failure, but shearing-off failure only occurs on the roughest fractures. The fluid overpressure ratio is influenced by the fluid diffusion rate, which determines the homogeneity of fluid pressure distribution over the fracture. The injection-induced instability exhibits quasi-dynamic sliding and is insignificantly correlated with roughness.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Engineering, Geological
Changdong Ding, Yihu Zhang, Jiebing Zhu, Dawei Hu, Hui Zhou
Summary: The activation of fractures and faults associated with stress perturbations is common in engineering applications. Understanding the hydraulic response mechanisms governing fractures and faults activation is crucial to mitigate seismicity induced by deep resource extraction. Laboratory experiments on fracture activation induced by fluid injection and unloading normal stress were conducted to investigate their behavior. The results showed that fluid pressurization induced quasi-dynamic sliding, while unloading normal stress induced dynamic slip. The fracture activation mechanism exhibited a transition from dilation to slip due to severe asperity damage caused by fluid injection. The study also discussed the fracture frictional instability characteristics and found that unloading normal stress triggers faster slip rates and greater energy release compared to fluid injection, indicating a higher potential for seismic hazards.
Article
Metallurgy & Metallurgical Engineering
Xiao Ma, Gui-ling Wang, Da-wei Hu, Hui Zhou
Summary: In this study, hydraulic fracturing experiments were conducted on granite at room temperature and 200 degrees C under different true triaxial stress to analyze their different fracturing mechanisms. The results showed that hydraulic fracturing at 200 degrees C can significantly reduce the breakdown pressure and fracture initiation pressure compared to hydraulic fracturing at room temperature. Moreover, the increase in fracturing volume at 200 degrees C was caused by the increment of micro-scale crack in the fractured sample, as observed from the nuclear magnetic resonance result.
JOURNAL OF CENTRAL SOUTH UNIVERSITY
(2023)
Article
Energy & Fuels
Luis Salala, Jonathan Argueta, Noel Lopez, Osmany Aparicio, Diana Martinez, Pedro Santos, Arturo Quezada, Oziel Garcia, Jose Erazo, Hiroyuki Yamagishi, Noriyoshi Tsuchiya
Summary: Geothermal systems have significant potential to replace reliance on fossil fuels. El Salvador, being tectonically active, already supplies a significant portion of its electricity demand using volcanic geothermal fields. The study compares different geothermal areas in El Salvador and highlights the controlling factors in the characteristics of geothermal reservoirs.
Article
Energy & Fuels
Lin Jia, Kewen Li, Yun Han, Chi Zhang, Lipeng Zhao
Summary: This study proposes a new approach of retrofitting abandoned oil wells into geothermal wells, and investigates the effects of different parameters on the performance using a numerical model. The results show that the enhanced fracture system significantly improves the efficiency of geothermal energy extraction, and optimal design should control the flow rate and use proppant.
Article
Energy & Fuels
K. H. Kvalsvik, H. Holmberg, R. K. Ramstad, K. Midttomme
Summary: This study proposes a new analytical equation that takes into account the advective heat in fractured rock, improving the accuracy of measuring thermal properties in borehole heat exchangers. The equation is applicable to all thermal response tests and provides a cost-effective alternative to numerical modelling.
Article
Energy & Fuels
Ronald Dipippo
Summary: This paper presents a technique of further preheating the working fluid in geothermal binary plants using extraction turbines, and evaluates the performance at various geofluid temperatures through working equations. The results indicate that this approach can be equally effective in geothermal binary plants as it is in conventional nuclear power plants.
Article
Energy & Fuels
Y. A. Popov, E. M. Chekhonin, E. G. Savelev, D. A. Ostrizhniy, A. B. Shakirov, R. A. Romushkevich, E. A. Babich, B. E. Andreyev, M. Y. Spasennykh, I. A. Sannikova
Summary: This paper describes the results of experimental geothermal studies on the formation surrounding the Savitskaya-300 well in the Volga-Ural oil and gas basin. The study found high thermal heterogeneity and anisotropy in the formation. The paper provides important data on thermal properties and heat flow variations in the well.
Article
Energy & Fuels
Viren Thakore, Hong Wang, Jy-An Wang, Yarom Polsky, Fei Ren
Summary: This paper focuses on the stability of foam-based fracturing fluid under high temperature and high pressure conditions. It is of significant importance for the development of foam fracturing fluid as an alternative to conventional water-based fracturing fluid in Enhanced Geothermal System (EGS). Experimental results show that with the appropriate selection of surfactants and stabilizing agents, stable foams can be obtained. Analytical models are developed to predict the foam stability for different foam compositions, considering the effects of temperature and pressure.
Article
Energy & Fuels
Hong Chang, Sheng Jiang, Haozhi Jiang, Yunjie Li, Zhengheng Gan, Songying Zhao
Summary: This study compared the bearing performance between phase change energy piles (GPEP) and traditional energy piles (TEP) using indoor modeling tests and theoretical formulas. The results showed that GPEP increased the ultimate bearing capacity of a single pile by about 13% compared to TEP. Additionally, the phase change materials effectively restricted the temperature-drag response of energy piles.
Article
Energy & Fuels
Qiang Zhang, Tiago Alves
Summary: This study investigates the influence of salt structures and faults on the geothermal potential in the Cleaver Bank High, Southern North Sea, using high-quality 3D seismic reflection data and bottom-hole temperature data. The results show that salt structures and faults play a significant role in the geothermal gradient, with higher gradients found on the footwalls of faults. Three potential geothermal exploration targets are identified based on the findings.
Article
Energy & Fuels
Hubert Langevin, Nicolo Giordano, Jasmin Raymond, Louis Gosselin, Martin Bourbonnais
Summary: This study evaluates the efficiency and cost of solar-assisted geothermal systems in a subarctic climate, and offers recommendations for optimizing ground heat exchanger configurations.
Article
Energy & Fuels
Lei Chen, Jinchuan Zhang, Longfei Xu, Shijing Chen, Qianchao Li, Yuhang Sun, Jie Li, Xingxu Zhao
Summary: This study assesses the geothermal water circulation process of a granite geothermal system in the Lancang area, Yunnan using water chemistry and isotope analysis techniques. The results show that the geothermal water originates from atmospheric precipitation and the granite pluton serves as the main heat source. Additionally, the fault system plays an important role in the discharge and mixing of hot and cold water.
Review
Energy & Fuels
Md Azhar, Somenath Mondal, Anh Minh Tang, Akhileshwar K. Singh
Summary: Contemporary geotechnical engineering practice involves the design and construction of structures that encounter thermal cycles. Understanding the effect of temperature on soil mechanical properties is challenging, but there have been significant contributions from numerous studies. However, to date, there is no comprehensive review that provides a holistic development of the subject and its connection to field applications.
Article
Energy & Fuels
Mark White, Yaroslav Vasyliv, Koenraad Beckers, Mario Martinez, Paolo Balestra, Carlo Parisi, Chad Augustine, Gabriela Bran-Anleu, Roland Horne, Laura Pauley, Giorgia Bettin, Theron Marshall, Anastasia Bernat
Summary: The study presents a comprehensive numerical modeling of closed-loop geothermal systems (CLGSs) and develops a publicly accessible web application for feasibility studies. The results suggest that competitive levelized cost of heat (LCOH) can be achieved, but significant reductions in drilling costs are required to achieve competitive levelized cost of electricity (LCOE). A site-based case study for multi-lateral systems and the analysis of permeable wet rock are also provided, indicating the potential for improved power production with higher reservoir permeability and temperature.
Article
Energy & Fuels
Xiaoming Tian, Oleg Volkov, Denis Voskov
Summary: In this study, an efficient and flexible adjoint-based framework is proposed for history matching and forecasting geothermal energy extraction. The framework reduces the parameter space using Principal Component Analysis and speeds up the iteration process using the adjoint method. Operator-based linearization is used for efficient calculation and matrix assembly. The framework is demonstrated to be highly efficient for a heterogeneous reservoir with multiple realizations, generating reliable history-matching results.
Article
Energy & Fuels
Asrillah Asrillah, Agus Abdullah, Klaus Bauer, Ben Norden, Charlotte M. Krawczyk
Summary: At the Gross Scho center dot nebeck geothermal research platform in the NE German Basin, the degree and direction of azimuthal velocity anisotropy caused by sub-vertical fracturing were determined through analysis of 3-D seismic reflection data. The observed anisotropy above the Zechstein salt roughly correlates to fault structures formed by an upwelling salt pillow, while below the salt, the less pronounced anisotropy and interpreted fracturing follow the trend of the regional stress field.
Article
Energy & Fuels
Kyosuke Okamoto, Yusuke Mukuhira, Dian Darisma, Hiroshi Asanuma, Hirokazu Moriya
Summary: Microseismic monitoring is crucial in geothermal development, and manual phase picking for seismic data is time-consuming. Existing deep learning phase pickers may face challenges in geothermal fields due to their unique features. This study focuses on developing a specialized deep learning model for local seismic networks in geothermal fields, allowing automatic hypocenter determinations and revealing subsurface fine structures.
