Study on the Underground Thermal Environment around Wells for a Design Method of Open-Loop Geothermal System

Bae, Sangmu; Kim, Hongkyo; Kim, Hyeon-Woo; Nam, Yujin

doi:10.17664/ksgee.2017.13.1.014

Cited by 3 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Park et al [12] investigated the isotopic compositions and chemical of groundwater as the GWHP system was operated to understand its geochemical properties. Bae et al [13] set the operation and ground as case conditions and quantitatively showed the changes of groundwater level and groundwater temperature according to the operation of a multi-well system. However, when a multi well open-loop system is used for a long term, there is a concern that clogging may occur.…”

Section: Introductionmentioning

confidence: 99%

Development of a Multi-Well Pairing System for Groundwater Heat Pump Systems

et al. 2018

Self Cite

View full text Add to dashboard Cite

Groundwater heat pump systems (GWHPs) can achieve higher coefficient of performance (COP) than air-source heat pump systems by using the relatively stable temperature of groundwater. Among GWHPs, multi-well systems have lower initial investment costs than conventional closed-loop geothermal systems, because they typically require installation of fewer boreholes for the same building load. However, the performance of GWHPs depends significantly on the groundwater properties, such as groundwater temperature, permeability and water quality. Moreover, pumping and injecting of groundwater during long-term operation may lead to problems such as overflow or clogging of the wells. In order to ensure reliable energy from ground sources, the development of sustainable operation methods for multi-well systems is essential for preventing overflow and well clogging. In this study, we have developed a pairing technology that connects the injection and supply wells through a spillway. This pairing technology can be used to control groundwater levels in wells and can be sustainably operated. To accurately estimate the performance of a multi-well system with the proposed pairing technology, the heating and cooling performance of the developed system was compared to that of a standing column well (SCW) system in a field-scale experiment. Furthermore, the effects of the multi-well pairing system on groundwater levels in the injection well were analyzed by numerical simulation. Moreover, in order to decide the required conditions of the multi-well pairing system, case studies were conducted under various hydraulic conductivity and pumping conditions.

show abstract

Section: Introductionmentioning

confidence: 99%

Development of a Multi-Well Pairing System for Groundwater Heat Pump Systems

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…지상으로 양수된 가열된 물은 열 교환기를 거쳐서 증기터빈을 이용 하여 전기를 생산한다 (Jiang et al, 2016;Lee and Chung, 2020). 대표적으로 낮은 투수성을 가진 기반암은 화강암으 로 (Chandrasekharam et al, 2015) (Carlson et al, 2018;Nouraliee, 2000) (Scherff, 2016;Cladouhos et al, 2016 (Bae et al, 2017;Park et al, 2013) 공급하는 지열발전소로서 수십 년 동안 가동되어 왔다 (Sahar et al, 2010;Mutonga, 2007 Caulk et al, 2016;Luo et al, 2018).…”

unclassified

Geochemical Effect of Geothermal Water Flushing during Enhanced Geothermal Systems Operation

Lee¹,

Chung²

2021

ksmer

View full text Add to dashboard Cite

Scale production occurs during enhanced geothermal system (EGS) processes due to various conditions. The production of scales in pipes or fractured reservoir narrows the diameter of the injection and production well, decreasing permeability and reducing EGS efficiency. However, geothermal water flushing during EGS processes can be implemented to recover the permeability. In this study, an experimental instrument to simulate a geothermal system was applied to observe the chemical composition change of core and water samples. To simulate the EGS, an experiment was conducted by injecting the geothermal fluid in several cycles to the fractured core. Results showed that Si ions decreased in the geothermal fluid and permeability decreased due to precipitation. Thereafter, flushing was applied, and dissolution occurred inside the fracture, increasing the permeability.

show abstract

Smart Heating and Cooling Heat Pump System by Standing Column Well and Cross-Mixing Balancing Well Heat Exchangers

Kim

Lim

et al. 2020

Applied Sciences

View full text Add to dashboard Cite

Standing column well (SCW) geothermal heat exchanger permits a bleeding discharge of less than 20% in the event of a maximum load, which is an inappropriate method of using underground water. In this study, the existing operational method of two adjacent SCW geothermal heat exchangers, each with a single well, was modified. This technology aims to improve the coefficient of performance (COP) of the geothermal system by fundamentally preventing underground water discharge and maintaining a constant temperature of the underground heat exchanger. To curb the bleed water discharge, two balancing wells of cross-mixing methods were employed. The result of the cooling and heating operations with the existing SCW heat exchange system and the balancing well cross-combined heat exchange system showed that the measured COP increases by 23% and 12% during the cooling and heating operations, respectively. When operating with a balanced well cross-mixed heat exchange system, the initial temperature of the underground was constant with a small standard deviation of 0.08–0.12 °C.

show abstract

Study on the Underground Thermal Environment around Wells for a Design Method of Open-Loop Geothermal System

Cited by 3 publications

References 0 publications

Development of a Multi-Well Pairing System for Groundwater Heat Pump Systems

Development of a Multi-Well Pairing System for Groundwater Heat Pump Systems

Geochemical Effect of Geothermal Water Flushing during Enhanced Geothermal Systems Operation

Smart Heating and Cooling Heat Pump System by Standing Column Well and Cross-Mixing Balancing Well Heat Exchangers

Contact Info

Product

Resources

About