An experiment on heat extraction from a deep geothermal well using a downhole coaxial open loop design

被引:64
作者
Dai, Chuanshan [1 ,2 ]
Li, Jiashu [2 ]
Shi, Yu [2 ]
Zeng, Long [2 ]
Lei, Haiyan [1 ,2 ]
机构
[1] Minist Educ, Key Lab Efficient Utilizat Low & Medium Grade Ene, Tianjin 300072, Peoples R China
[2] TianJin Univ, Sch Mech Engn, Tianjin 300072, Peoples R China
基金
中国国家自然科学基金;
关键词
Deep geothermal well; Downhole coaxial; Open loop; Heat extraction rate; Space heating; PERFORMANCE; EXCHANGER;
D O I
10.1016/j.apenergy.2019.113447
中图分类号
TE [石油、天然气工业]; TK [能源与动力工程];
学科分类号
0807 ; 0820 ;
摘要
We report a field heat extraction test from a deep geothermal well using a downhole coaxial open loop design in Tanggu, Tianjin China, which is different from most previous studies in that the well casing is closed to the geothermal reservoir. A downhole pump installed in the inner tube pumped the geothermal fluids to the surface. After releasing heat by flowing through a plate heat exchanger, the geothermal fluid returned to the aquifer completely and naturally by gravity through the annular section between the inner tube and the borehole wall. The proposed design realizes a sustainable and clean way of "no water withdrawn but heat only" in geothermal utilization. The experimental test well was used as a reinjection well for two years, and the maximum measured temperature in the well before the experiment was only 51 degrees C. The experimental results show that the proposed configuration worked very well in extracting heat from a deep geothermal reservoir. The system's stable heat output can reach approximately 275 kW after two weeks of continuous heat extraction, which was much larger than the theoretically calculated value for deep borehole heat exchangers by using the heat conduction model.
引用
收藏
页数:7
相关论文
共 25 条
[1]   The wellbore heat exchangers: A technical review [J].
Alimonti, C. ;
Soldo, E. ;
Bocchetti, D. ;
Berardi, D. .
RENEWABLE ENERGY, 2018, 123 :353-381
[2]  
Dai C., 2008, GRC Transactions, V32, P317
[3]  
Dai C, 2016, Patent, Patent No. [ZL201621044381.4, 201621044381]
[4]  
Dai C., 2011, T GEOTHERM RESOUR CO, V35, P1077
[5]   Measurements and Design Calculations for a Deep Coaxial Borehole Heat Exchanger in Aachen, Germany [J].
Dijkshoorn, Lydia ;
Speer, Simon ;
Pechnig, Renate .
INTERNATIONAL JOURNAL OF GEOPHYSICS, 2013, 2013
[6]  
Doelling R, 2010, P WORLD GEOTH C 2010
[7]   Rotorua field experiment. Downhole heat exchanger performance [J].
Freeston, D.H. ;
Dunstall, M.G. .
Geothermics, 1992, 21 (1-2) :305-317
[8]  
GEL University of St Andrews & Arup, 2016, AB EXH C CTR
[9]  
Gnielinski V, 1975, NASA STIRECON TECHNI, V75, P8
[10]   Thermal evaluation of coaxial deep borehole heat exchangers [J].
Holmberg, Henrik ;
Acuna, Jose ;
Naess, Erling ;
Sonju, Otto K. .
RENEWABLE ENERGY, 2016, 97 :65-76