EFFECTS OF GEOLOGICAL PARAMETERS ON LONG-TERM THERMAL EXTRACTION CHARACTERISTICS OF MEDIUM-DEEP GEOTHERMAL WELL

Han Ershuai; Li Fengcui; Liang Lei; Xu Yanhui; Ju Rui; Liu Shuai

doi:10.19912/j.0254-0096.tynxb.2020-0406

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Acta Energiae Solaris Sinica ›› 2022, Vol. 43 ›› Issue (2) : 62-68. DOI: 10.19912/j.0254-0096.tynxb.2020-0406

EFFECTS OF GEOLOGICAL PARAMETERS ON LONG-TERM THERMAL EXTRACTION CHARACTERISTICS OF MEDIUM-DEEP GEOTHERMAL WELL

Han Ershuai¹, Li Fengcui¹, Liang Lei¹, Xu Yanhui¹, Ju Rui¹, Liu Shuai²

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Abstract

Based on the heat transfer mechanism of medium-deep geothermal well, numerical analysis is carried out to investigate the effects of different geological parameters on the single-well heat extraction load （HEL）, energy efficiency coefficient, heat pump unit COP, and rock-soil temperature during the long-term operation. The results indicate that rock-soil thermal conductivity （RTC） has a significant effect on the decline ratios of single-well HEL and energy efficiency coefficient with operating year. The lower RTC, the larger decline ratios. At 2.0 W/（m·K） of RTC, both single-well HEL and energy efficiency coefficient in the 30 th year decline by 13.7% compared to those in the first year. Geothermal temperature gradient largely affects the decline degree of heat pump unit COP with operating year. The decline ratio increases with an increasing geothermal temperature gradient. Additionally, under different geological parameters, the influence radius of rock and soil temperature increases proportionally with operating years.

Key words

geothermal well / geologyical parameters / energy efficiency coefficient / long-term thermal extraction / rock-soil temperature / medium-deep layer

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Han Ershuai, Li Fengcui, Liang Lei, Xu Yanhui, Ju Rui, Liu Shuai. EFFECTS OF GEOLOGICAL PARAMETERS ON LONG-TERM THERMAL EXTRACTION CHARACTERISTICS OF MEDIUM-DEEP GEOTHERMAL WELL[J]. Acta Energiae Solaris Sinica. 2022, 43(2): 62-68 https://doi.org/10.19912/j.0254-0096.tynxb.2020-0406

References

[1] TOMASINI-MONTENEGRO C, SANTOYO-CASTELAZO E, GUJBA H, et al.Life cycle assessment of geothermal power generation technologies: an updated review[J]. Applied thermal engineering, 2017, 114: 1119-1136.
[2] SUTER C, JOVANOVIC Z R, STEINFELD A.A1 kW_e thermoelectric stack for geothermal power generation modeling and geometrical optimization[J]. Applied energy, 2012, 99: 379-385.
[3] ØSTERGAARD P A, LUND H.A renewable energy system in Frederikshavn using low-temperature geothermal energy for district heating[J]. Applied energy, 2011, 88(2): 479-487.
[4] SAPINSKA-SLIWA A, ROSEN M A, GONET A,et al. Deep borehole heat exchangers-A conceptual and comparative review[J]. International journal of air-conditioning and refrigeration, 2016, 24(1): 1630001.1-1630001.15.
[5] KNOBLAUCH T A K, TRUTNEVYTE E, Stauffacher M. Siting deep geothermal energy: acceptance of various risk and benefit scenarios in a Swiss-German cross-national study[J]. Energy policy, 2019, 128: 807-816.
[6] 刘俊, 蔡皖龙, 王沣浩, 等. 深层地源热泵系统实验研究及管井结构优化[J]. 工程热物理学报, 2019, 40(9): 2143-2150.
LIU J, CAI W L, WANG F H, et al.Experimental study and tube structure optimization of deep borehole ground source heat pump[J]. Journal of engineering thermophysics, 2019, 40(9): 2143-2150.
[7] 邓杰文, 魏庆芃, 张辉, 等. 中深层地热源热泵供暖系统能耗和能效实测分析[J]. 暖通空调, 2017, 47(8): 150-154.
DENG J W, WEI Q P, ZHANG H, et al.On-site measurement and analysis on energy consumption and energy efficiency ratio of medium-depth geothermal heat pump systems for space heating[J]. Heating ventilation and air condition, 2017, 47(8): 150-154.
[8] 韩二帅, 张家护, 鲁冰雪, 等. 中深层地热能供热技术综述及工程实例[J]. 区域供热, 2019(2): 79-83, 95.
HAN E S, ZHANG J H, LU B X, et al.Summary and engineering cases of medium-depth geothermal heating technology[J]. District heating, 2019(2): 79-83, 95.
[9] KOTLER S.Abandoned oil and gas wells are leaking[EB/OL]. http://www.zcommunications.org/abandoned oil and gas well are leaking by steven kotler.
[10] BARBIER E.Geothermal energy technology and current status: an overview[J]. Renewable and sustainable energy reviews, 2002, 6(1-2): 3-65.
[11] LIU J, WANG F H, CAI W L, et al.Numerical study on the effects of design parameters on the heat transfer performance of coaxial deep borehole heat exchanger[J]. International journal of energy research, 2019, 43(12): 6337-6352.
[12] FANG L, DIAO N R, SHAO Z K, et al.A Computationally efficient numerical model for heat transfer simulation of deep borehole heat exchangers[J]. Energy and buildings, 2018, 167: 79-88.
[13] CHEN C F, SHAO H B, NAUMOV D, et al.Numerical investigation on the performance, sustainability, and efficiency of the deep borehole heat exchanger system for building heating[J]. Geothermal energy, 2019, 7: 18.
[14] SONG X Z, WANG G S, SHI Y, et al.Numerical analysis of heat extraction performance of a deep coaxial borehole heat exchanger geothermal system[J]. Energy, 2018, 164: 1298-1310.
[15] 陶文铨. 数值传热学[M]. 西安: 西安交通大学出版社, 2001: 78-88.
TAO W Q.Numerical heat transfer[M]. Xi'an: Xi'an Jiaotong University Press,2001: 78-88.