Md Nahin Mahmood^*, Boyun Guo

Energy Engineering, Vol.120, No.12, pp. 2707-2720, 2023, DOI:10.32604/ee.2023.042996

Abstract The energy industry faces a significant challenge in extracting natural gas from offshore natural gas hydrate (NGH) reservoirs, primarily due to the low productivity of wells and the high operational costs involved. The present study offers an assessment of the feasibility of utilizing geothermal energy to augment the production of natural gas from offshore gas hydrate reservoirs through the implementation of the methane-CO₂ swapping technique. The present study expands the research scope of the authors beyond their previous publication, which exclusively examined the generation of methane from marine gas hydrates. Specifically, the current investigation explores the feasibility of utilizing the… More >

Yanyong Wang^1,2, Kunpeng Zhong¹, Xiaoguang Wang^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09443

Abstract The storage of solar energy in the subsurface in terms of heat is considered as a promising way for energy storage and conversion in future, which has a great potential to solve the temporal and spatial mismatch between energy demand and supply. Thermal energy storage in deep saline aquifers is capable to convert intermittent solar energy into high temperature stable geothermal energy. In this study, we propose a new solar energy storage and conversion system in which solar energy is firstly converted into heat using parabolic trough and then thermal energy storage in deep saline aquifer is conducted by high… More >

Huashan Li¹, Xiaoshuang Zhao^1,2, Sihao Huang^1,2, Lingbao Wang¹, Jiongcong Chen^1,*

Energy Engineering, Vol.120, No.8, pp. 1817-1835, 2023, DOI:10.32604/ee.2023.027668

Abstract Process heating constitutes a significant share of final energy consumption in the industrial sector around the world. In this paper, a high-temperature heat pump (HTHP) using flash tank vapor injection technology (FTVI) is proposed to develop low-temperature geothermal source for industrial process heating with temperature above 100°C. With heat sink output temperatures between 120°C and 150°C, the thermo-economic performance of the FTVI HTHP system using R1234ze(Z) as refrigerant is analyzed and also compared to the single-stage vapor compression (SSVC) system by employing the developed mathematical model. The coefficient of performance (COP), exergy efficiency (η_exe), net present value (NPV) and payback… More >

Yashar Aryanfar^1,*, Jorge Luis García Alcaraz²

Energy Engineering, Vol.120, No.2, pp. 263-275, 2023, DOI:10.32604/ee.2023.022587

Abstract The usage of renewable energies, including geothermal energy, is expanding rapidly worldwide. The low efficiency of geothermal cycles has consistently highlighted the importance of recovering heat loss for these cycles. This paper proposes a combined power generation cycle (single flash geothermal cycle with trans-critical CO₂ cycle) and simulates in the EES (Engineering Equation Solver) software. The results show that the design parameters of the proposed system are significantly improved compared to the BASIC single flash cycle. Then, the proposed approach is optimized using the genetic algorithm and the Nelder-Mead Simplex method. Separator pressure, steam turbine output pressure, and CO₂ turbine… More > Graphic Abstract

Nugroho Agung Pambudi^1,*, Santiko Wibowo¹, Ranto¹, Lip Huat Saw²

Energy Engineering, Vol.118, No.5, pp. 1565-1576, 2021, DOI:10.32604/EE.2021.016642

Abstract Organic Rankine Cycle (ORC) is one of the solutions to utilize a low temperature geothermal fluid for power generation. The ORC system can be placed at the exit of the separator to extract energy from brine. Furthermore, one of the main components of the system and very important is the pump. Therefore, in this research, the pump rotation is examined to investigate the effect on power output and energy efficiency for low temperature geothermal fluid. The rotation is determined by using an inverter with the following frequencies: 7.5, 10, 12.5, 15 and 17.5 Hz, respectively. R-134 working fluid is employed… More >

Yiya Wang, Hailong Yu^*, Shucheng Wu, Li Liu, Liuyang Huang, Baozhong Zhu, Yunlan Sun, Enhai Liu

Energy Engineering, Vol.118, No.4, pp. 797-823, 2021, DOI:10.32604/EE.2021.014467

Abstract Hot Dry Rock (HDR) is the most potential renewable geothermal energy in the future. Enhanced Geothermal System (EGS) is the most effective method for the development and utilization of HDR resources, and fractures are the main flow channels and one of the most important conditions for studying heat transfer process of EGS. Therefore, the heat transfer process and the heat transfer mechanism in fractures of EGS have been the hot spots of research. Due to the particularity of the mathematical models of heat transfer, research in this field has been at an exploratory stage, and its methods are mainly experimental… More >

Sulardjaka Sulardjaka^1,*, Sri Nugroho¹, Norman Iskandar¹, Agus P. Adi¹, Deni F. Fitriyana²

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 385-395, 2021, DOI:10.32604/fdmp.2021.011784

Abstract Zeolite A has been successfully synthesized from geothermal waste with natrium aluminate and natrium silicate using conventional (C-H) and microwave heating (M-H) for the hydrothermal treatment. The products obtained for different aging times have been characterized using X-Ray Diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). It is shown that with the M-H process, zeolite can be formed at relatively low temperature (100°C) in a relatively short time (40 min). The crystallization of zeolite A has been found to be generally promoted by an increase of aging and synthesis time; however, it has also been observed… More >

Jingying Li¹, Tiejun Zhu¹, Fengming Li¹, Dong Wang¹, Xianbiao Bu², Lingbao Wang^2,*

Energy Engineering, Vol.118, No.3, pp. 517-534, 2021, DOI:10.32604/EE.2021.014464

Abstract The single well geothermal heating (SWGH) technology has attracted extensive attention. To enhance heat extraction from SWGH, a mathematical model describing heat transfer is set up, and the key influence factor and heat transfer enhancement method are discussed by thermal resistance analysis. The numerical results show that the thermal resistance of rock is far greater than that of well wall and fluid. So, reducing rock thermal resistance is the most effective method for enhancing the heat extraction power. For geothermal well planning to drill: rock thermal resistance can be reduced by increasing well diameter and rock thermal conductivity; the temperature… More >

Hongwei Zhang^1,2, Zhijun Wan³, Yixin Zhao^1,2, Yuan Zhang³, Yulong Chen^2,*, Junhui Wang^3,*, Jingyi Cheng³

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.2, pp. 443-455, 2021, DOI:10.32604/cmes.2021.013179

Abstract In the enhanced geothermal system (EGS), the injected fluid will induce shear sliding of rock fractures (i.e., hydroshearing), which consequently, would increase the fracture aperture and improve the heat transfer efficiency of the geothermal reservoir. In this study, theoretical analysis, experimental research and numerical simulation were performed to uncover the permeability and heat transfer enhancement mechanism of the Hot-Dry-Rock (HDR) mass under the impact of shearing. By conducting the direct shear test with the fractured rock samples, the evolution process of fracture aperture during the shearing tests was observed, during which process, cubic law was adopted to depict the rock… More >