地热单井原位换热取热技术研究现状及展望

doi:10.13745/j.esf.sf.2024.7.19

摘要/Abstract

摘要：

地热能是一种资源分布广泛,稳定可持续,清洁低碳,且唯一以热能形式存在的可再生能源,地热能的高效开发利用不仅可以满足我国北方地区的建筑供热需求,也可缓解我国电力短缺,对实现我国“双碳”战略目标有重要意义。地热能“宜热用热”,较其他可再生能源在建筑供热方面具有天然优势,但目前我国地热能利用仅占我国能耗的1.5%左右,远低于我国建筑能耗的1/3能源消耗占比。我国地热直接利用规模多年来居世界首位,但浅层地源热泵供热形式占60%左右,传统地热能利用相对占比较低,主要原因在于传统的地热抽灌模式依赖于当地水文地质条件,某些砂岩地层回灌困难或不经济,为此管理部门加强了地热井管理以避免地下水位下降较快的现象。近年来,“取热不取水”的地热单井取热技术受到广泛关注,此技术无回灌问题,适应我国当今的能源开发利用形势,有很好的应用前景。本文对地热单井换热取热技术的研究与应用现状进行简要综述,重点总结了国内外有关中深层“取热不取水”地热单井换热取热技术的研究现状,分析了不同单井强化取热技术的基本原理与不足,强调“因地制宜”实现单井原位取热技术的重要性,提出中深层地热单井循环取热技术是一种环境友好、可持续稳定的供热模式,可有效解决我国北方地区建筑的冬季供热问题。随着打井技术的不断进步,此技术有一定的市场竞争力;建议出台针对“取热不取水”或“取热不耗水”单井取热技术的管理政策,这对进一步提高我国的地热能利用规模,实现“双碳”目标有重要意义。

关键词: 地热, 单井, 取热不取水, 可持续利用

Abstract:

Geothermal energy is a widely distributed, stable, sustainable, clean, and low-carbon renewable energy resource, and the only renewable energy that exists in the form of thermal energy. Efficient development and utilization of geothermal energy can not only meet the needs of building heating in northern China but also alleviate the country’s power shortages. This is of significant importance for achieving China’s dual carbon (carbon peak and carbon neutrality) goals. Used best for heating, geothermal energy poses a natural advantage over other renewable energies in building heating. Currently, however, geothermal energy utilization in China only accounts for ~1.5% of the country’s total energy consumption, far below the one-third share of energy consumption by buildings. For many years China has maintained a worldwide leader in geothermal direct use, but ~60% of which comes from shallow ground-source heat pumps. The traditional use of geothermal energy is relatively low, mainly because the conventional geothermal production and reinjection modes largely rely on the local hydrogeological conditions, and reinjection is difficult or uneconomical in some sandstone formations. As a result, government have tightened control on geothermal resources to prevent the rapid decline of water levels. In recent years, the “no-water-withdrawal-heat-only” single-well geothermal system has gained widespread attention. This technology eliminates reinjection issues and adapts well to the current energy development and utilization situation in China, offering excellent application prospects. This paper provides a brief overview of the research and application status of single-well heat extraction technology, focusing on the status of interactional and domestic researches on the no-water-withdrawal-heat-only technology. The basic principles and shortcomings of different single-well technologies are analyzed, emphasizing the importance of implementing site-specific in-situ technologies. The paper proposes that deep single-well heat extraction technology is an environmentally friendly, sustainable, and stable heating model that can effectively address the issue of building heating in winter in northern China. This technology has gained a certain level of market competitiveness with the advancement of drilling technology. It is recommended that relevent management policies should be formulated, which are crucial for promoting geothermal energy utilization in China and achieving the “dual carbon” goals.

Key words: geothermal energy, single-well, no water withdrawn but heat only, sustainable utilization

中图分类号:

P314

戴传山, 刘东喜, 李嘉舒, 雷海燕, 陈书焕, 陈谦涵, 王启龙. 地热单井原位换热取热技术研究现状及展望[J]. 地学前缘, 2024, 31(6): 204-214.

DAI Chuanshan, LIU Dongxi, LI Jiashu, LEI Haiyan, CHEN Shuhuan, CHEN Qianhan, WANG Qilong. Single-well in-situ heat extraction technology—a review and perspectives[J]. Earth Science Frontiers, 2024, 31(6): 204-214.

图/表 9

图1 几种典型地热单井原位换热取热技术(据文献[10⇓⇓⇓⇓⇓-16]修改)

Fig.1 Typical techniques of heat extraction from a single geothermal well. Modified after [10⇓⇓⇓⇓⇓-16].

图2 几种典型浅层地热单井井下换热器(DHE)结构设计(据文献[22⇓⇓-25]修改) a—单U形管;b—外套对流增速管;c—侧置对流增速管;d—空压泵循环。

Fig.2 Typical designs of shallow downhole heat exchangers. Modified after [22⇓⇓-25].

图3 中深层闭式单井换热取热技术研究发表论文数 a—论文发表数随年度变化; b—论文发表前列国家。

Fig.3 Statistics of published research papers on deep borehole heat exchangers

图4 全国中深层闭式单井换热取热技术专利申请件数 a—专利申请件数随年度变化; b—不同省份专利申请数。

Fig.4 Number of patent applications related to DBHE in China

表1 中深层单井取热试验实例

Table 1 Summary of field tests on heat extraction from a single geothermal well

文献	井深/m	井底温度/℃	热输出/kW	延米功率/(W·m^-1)	试验地点
Morita^{a [27]}	876.5	110.3	76	86	美国,Hawaii
Kohl^a[28]	1 213	45	80	66	瑞士,Weissbad
Kohl^{a [29]}	2 302	78	100	43	瑞士,Weggis
Dijkshoorn^{a [30]}	2 500	85	117	47	德国,Aachen
Wang^{a [31]}	2 000		286	143	中国,西安
Deng^{a [32]}	2 000 2 000 2 000 2 500 2 000		258 158 288 273 122	129 79 144 109 61	中国,西安
卜宪标 $a$ ^[33]	2 605	85	448.49	172	中国,青岛
Zhan $g a$ ^[34]	1 800	57	134	75	中国,雄安
Huan $g a$ ^[35]	2 044	107.3		238	中国,松原
L $i a$ ^[36]	2 539	89	480	189	中国,西安
Ma^{a [37]}	2 000		266	133	中国,天津
Huan $g b$ ^[16]	3 000	128	190	63	中国,唐山
Yi $n c$ ^[38]	1 751	71	930	531	中国,天津
Michael^{c [39]}	2 000	69	363	181.5	英国,Cornwall
李嘉舒 $c$ ^[26]	1 400	68	450	320	中国,唐山

表1 中深层单井取热试验实例

Table 1 Summary of field tests on heat extraction from a single geothermal well

文献	井深/m	井底温度/℃	热输出/kW	延米功率/(W·m^-1)	试验地点
Morita^{a [27]}	876.5	110.3	76	86	美国,Hawaii
Kohl^a[28]	1 213	45	80	66	瑞士,Weissbad
Kohl^{a [29]}	2 302	78	100	43	瑞士,Weggis
Dijkshoorn^{a [30]}	2 500	85	117	47	德国,Aachen
Wang^{a [31]}	2 000		286	143	中国,西安
Deng^{a [32]}	2 000 2 000 2 000 2 500 2 000		258 158 288 273 122	129 79 144 109 61	中国,西安
卜宪标 $a$ ^[33]	2 605	85	448.49	172	中国,青岛
Zhan $g a$ ^[34]	1 800	57	134	75	中国,雄安
Huan $g a$ ^[35]	2 044	107.3		238	中国,松原
L $i a$ ^[36]	2 539	89	480	189	中国,西安
Ma^{a [37]}	2 000		266	133	中国,天津
Huan $g b$ ^[16]	3 000	128	190	63	中国,唐山
Yi $n c$ ^[38]	1 751	71	930	531	中国,天津
Michael^{c [39]}	2 000	69	363	181.5	英国,Cornwall
李嘉舒 $c$ ^[26]	1 400	68	450	320	中国,唐山

图5 中深层单井单位延米换热取热功率与井深的关系

Fig.5 Plot of heat extraction rate per wellbore length vs. well depth

图6 模拟开式单井取热不同物理模型的温度场与流线 a—模型,温度场与流线(据文献[47]);b—模型,温度场与流线(据文献[48])。

Fig.6 Numerical simulation results on natural convection (in cavity partially filled with porous media), temperature contour and streamline using different physical models. Adapted from [47-48].

图7 开式单井试验结果与数值模拟结果对比(河北唐山)

Fig.7 Comparison of experimental and simulation results for heat extraction with a DOLGW design (Tangshan, Hebei, China)

图8 系统运行10年后的取热功率和出水温度

Fig.8 The heat extraction rate and outlet water temperature after 10 years of system operation

参考文献 46

[1]	陈焰华. 中国地热能产业发展报告[R]. 北京: 中国建筑工业出版社, 2021.
[2]	王贵玲, 蔺文静. 我国主要水热型地热系统形成机制与成因模式[J]. 地质学报, 2020, 94(7): 1923-1937.
[3]	LIN W J, WANG G L, GAN H N, et al. Heat source model for Enhanced Geothermal Systems (EGS) under different geological conditions in China[J]. Gondwana Research, 2023, 122: 243-259.
[4]	LUND J W, FREESTON D H, BOYD T L. Direct utilization of geothermal energy 2010 worldwide review[J]. Geothermics, 2011, 40(3): 159-180.
[5]	王贵玲, 蔺文静, 刘峰, 等. 地热系统深部热能聚敛理论及勘查实践[J]. 地质学报, 2023, 97(3): 639-660.
[6]	WANG G L, GAN H N, LIN W J, et al. Hydrothermal systems characterized by crustal thermally-dominated structures of southeastern China[J]. Acta Geologica Sinica (English Edition), 2023, 97(4): 1003-1013.
[7]	LIU D X, LEI H Y, LI J S, et al. Optimization of a district heating system coupled with a deep open loop geothermal well and heat pumps[J]. Renewable Energy, 2024, 223: 119991.
[8]	王贵玲, 刘彦广, 朱喜, 等. 中国地热资源现状及发展趋势[J]. 地学前缘, 2020, 27(1): 1-9. DOI
[9]	ALLIS R, JAMES R. Natural-convection promoter for geothermal wells[J]. Transactions-Geothermal Resources Council, 1980, 4: 409-412.
[10]	CHENG A. President’s page: geothermal energy: current and future[J]. The Leading Edge, 2022, 41(9): 588-589.
[11]	FREESTON D H, DUNSTALL M G. Rotorua field experiment: downhole heat exchanger performance[J]. Geothermics, 1992, 21(1/2): 305-317.
[12]	倪龙, 马最良. 含水层参数对同井回灌地下水源热泵的影响[J]. 天津大学学报, 2006, 39(2): 229-234.
[13]	ALIMONTI C, SOLDO E, BOCCHETTI D, et al. The wellbore heat exchangers: a technical review[J]. Renewable Energy, 2018, 123: 353-381.
[14]	HOLMBERG H, ACUÑA J, NÆSS E, et al. Deep borehole heat exchangers, application to ground source heat pump systems[C]//International Geothermal Association. Proceeding World Geothermal Congress. Melbourne, Australia, 2015: 15-29.
[15]	HUANG W B, CEN J W, CHEN J W, et al. Heat extraction from hot dry rock by super-long gravity heat pipe: a field test[J]. Energy, 2022, 247: 123492.
[16]	DAI C S, LI J S, LEI H Y. A technical review of heat extraction from a single deep geothermal well without net pumping fluids out of reservoir[C]//International Geothermal Association. Proceedings World Geothermal Congress. Beijing, China, 2023: 1470-1486.
[17]	北京市市场监督管理局. 中深层地热供热工程技术规范: DB 14/T 2386—2021[S]. 北京: 中国建材工业出版社, 2021.
[18]	陕西省住房和城乡建设厅. 中深层地热地埋管供热系统应用技术规程: DB J61/T 166—2020[S]. 北京: 中国建材工业出版社, 2020.
[19]	甘肃省住房和城乡建设厅. 无干扰地岩热供热系统工程技术规范: DB 62/T 3144—2018[S]. 北京: 中国建材工业出版社, 2018.
[20]	陕西省住房和城乡建设厅. 中深层地热井下换热供热工程技术标准: DB 13(J)/T 8429—2021[S]. 北京: 中国建材工业出版社, 2021.
[21]	DAI C S, CHEN Y. Classification of shallow and deep geothermal energy[J]. Transactions-Geothermal Resources Council, 2008, 32: 317-320.
[22]	CULVER G, REISTAD G M. Testing and modeling of downhole heat exchangers in shallow geothermal systems[J]. Transactions-Geothermal Resources Council, 1978, 2: 129-131.
[23]	XIE S M, DAI C S. The application of DHE combined with heat pump for Shallow geothermal energy uses[C]// Chinese Geophysical Society. Proceedings of the 27th Annual Conference of the Chinese Geophysical Society. Hunan, China, 2011: 1742-1766.
[24]	STEINS C, BLOOMER A, ZARROUK S J. Improving the performance of the down-hole heat exchanger at the Alpine Motel, Rotorua, New Zealand[J]. Geothermics, 2012, 44: 1-12.
[25]	孔彦龙, 陈超凡, 邵亥冰, 等. 深井换热技术原理及其换热量评估[J]. 地球物理学报, 2017, 60(12): 4741-4752. DOI
[26]	李嘉舒. 中深层地热单井循环换热系统取热特性研究[D]. 天津: 天津大学, 2023.
[27]	MORITA K, BOLLMEIER W S, MIZOGAMI H. An experiment to prove the concept of the downhole coaxial heat exchanger (DCHE) in Hawaii[J]. Transactions-Geothermal Resources Council, 1992, 16: 9-16.
[28]	KOHL T, SALTON M, RYBACH L. Data analysis of the deep borehole heat exchanger plant weissbad[C]// International Geothermal Association. Proceedings World Geothermal Congress. Kyushu-Tohoku, Japan, 2000: 3549-3564.
[29]	KOHL T, BRENNI R, EUGSTER W. System performance of a deep borehole heat exchanger[J]. Geothermics, 2002, 31(6): 687-708.
[30]	DIJKSHOORN L, SPEER S, PECHNIG R. Measurements and design calculations for a deep coaxial borehole heat exchanger in Aachen, Germany[J]. International Journal of Geophysics, 2013(1): 916541.
[31]	WANG Z H, WANG F H, LIU J, et al. Field test and numerical investigation on the heat transfer characteristics and optimal design of the heat exchangers of a deep borehole ground source heat pump system[J]. Energy Conversion and Management, 2017, 153: 603-615.
[32]	DENG J W, WEI Q P, LIANG M, et al. Field test on energy performance of medium-depth geothermal heat pump systems (MD-GHPs)[J]. Energy and Buildings, 2019, 184: 289-299.
[33]	卜宪标, 蒋坤卿. 地热单井连续和间歇供暖性能[J]. 中国科学: 技术科学, 2019, 49(12): 1514-1522.
[34]	ZHANG Y Q, YU C, LI G S, et al. Performance analysis of a downhole coaxial heat exchanger geothermal system with various working fluids[J]. Applied Thermal Engineering, 2019, 163: 114317.
[35]	HUANG Y B, ZHANG Y J, XIE Y Y, et al. Field test and numerical investigation on deep coaxial borehole heat exchanger based on distributed optical fiber temperature sensor[J]. Energy, 2020, 210: 118643.
[36]	LI C, GUAN Y L, LIU J H, et al. Heat transfer performance of a deep ground heat exchanger for building heating in long-term service[J]. Renewable Energy, 2020, 166: 20-34.
[37]	马玖辰, 易飞羽, 张秋丽, 等. 富水型热储层深井套管式换热器传热特性研究[J]. 化工学报, 2021, 72(8): 4134-4145. DOI
[38]	YIN H M, SONG C F, MA L, et al. Analysis of flow and thermal breakthrough in leaky downhole coaxial open loop geothermal system[J]. Applied Thermal Engineering, 2021, 194: 117098.
[39]	MICHALE A C, LAW R. The development and deployment of deep geothermal single well (DGSW) technology in the United Kingdom[J]. European Geologist Journal, 2017, 43: 63-68.
[40]	BEIER R A, ACUÑA J, MOGENSEN P, et al. Transient heat transfer in a coaxial borehole heat exchanger[J]. Geothermics, 2014, 51: 470-482.
[41]	LI J S, DAI C S, LEI H Y. The influence of thermal boundary conditions of wellbore on the heat extraction performance of deep borehole heat exchangers[J]. Geothermics, 2022, 100: 102325.
[42]	PAN A Q, LU L, CUI P, et al. A new analytical heat transfer model for deep borehole heat exchangers with coaxial tubes[J]. International Journal of Heat and Mass Transfer, 2019, 141: 1056-1065.
[43]	WANG Y R, WANG Y M, YOU S J, et al. Operation optimization of the coaxial deep borehole heat exchanger coupled with ground source heat pump for building heating[J]. Applied Thermal Engineering, 2022, 213: 118656.
[44]	WANG Y R, WANG Y M, YOU S J, et al. Mathematical modeling and periodical heat extraction analysis of deep coaxial borehole heat exchanger for space heating[J]. Energy and Buildings, 2022, 265: 112102.
[47]	CAROTENUTO A, MASSAROTTI N, MAURO A. A new methodology for numerical simulation of geothermal down-hole heat exchangers[J]. Applied Thermal Engineering, 2012, 48: 225-236.
[48]	DAI C S, LIU X Z, LEI H Y. Natural convection modeling in an open-ended square cavity partially filled with porous media[J]. Tansactions-Geothermal Resources Council, 2011, 35: 111-114.
[45]	李嘉舒, 戴传山, 雷海燕, 等. 地埋管换热器动态热负荷下地层温度场的解析解[J]. 水文地质工程地质, 2023, 50(2): 198-206.
[46]	ESKILSON P. Thermal analysis of heat extraction boreholes[D]. Lund: University of Lund, 1987.