• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.6 no.3
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• pp.315-324
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• 1994

The energy recovery efficiency(ERE) of an aquifer thermal energy storage system was calculated using curvilinear coordinate. The results of the calculation were compared with the experimental results, and agreed within 11% of the discrepancy. The variation of ERE was investigated as a function of the underground water natural velocity, the amount of the stored energy, and period of the energy recovery. The slower the natural velocity and shorter the recovery period, the higher ERE was yielded. Also it was found that increase in the amount of energy storage yields higher ERE, and carries out less influential ERE to the natural velocity. Reiterative usage of the aquifer as a thermal storage tends to gradually increase ERE. The result of this study implements that the aquifer thermal energy storage system is suitable for large cooling/heating loads, such as district cooling/heating.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.5 no.2
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• pp.102-110
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• 1993

An isothermal analysis was conducted to develop the design tool of an aquifer thermal energy storage system. Taejeon aquifer was chosen for the analysis, and the variation of FRE(Fluid Recovery Efficiency) with respect to the aquifer natural velocity and thermal load were investigated. The analysis results were compared with those of ATESSS(Aquifer Thermal Energy Storage System Simulator) and agreed within 2% of discrepancy. It is recommended, based on the result of this study, that the system may be suitable for a large volume of hot or chill thermal energy storage system, such as for district heating or cooling.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.23-31
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• 2015

Aquifer storage transfer and recovery (ASTR) is a type of managed aquifer recharge which entails injecting water into a storage well and recovering it from a different well. It has effects of natural purification when injected water passes through aquifer medium, and can be a good way of supplying water especially in a region with poor surface water quality. This study is about an on-going effort to introduce ASTR as a solution to source water problems in coastal areas. A pilot study is being conducted in the delta of the Nakdong River. A proactive management system is incorporated to ensure the water qulity in the process of drinking water process. The system is based on the Hazard Analysis and Critical Control Point (HACCP) which is a tool originated from the food industry in order to assess hazards and establish control systems for the safety of food product. In this paper, we analyze hazardous events which can occur in the entire water supply system using ASTR as a first step to the incorporation of HACCP to drinking water production process.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.9
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• pp.1780-1787
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• 1992

Experiments have been performed on the thermal behavior in a liquid saturated porous medium in a system to simulate a single well aquifer thermal energy storage system. The principal interests in this study are the combined effects of forced and natural convection. Significant buoyancy flow due to natural convection is developed quickly as the temperature difference between the injection and original aquifer temperature increases. Theoretical model under simplified assumptions (called simple buoyancy flow model in this study) has been developed. The results of this model agree well with the experiments. The effects of buoyancy flow on the recovery factor are also examined in this study.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.05a
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• pp.27-36
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• 2003

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.244-244
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• 2015

Managed Aquifer Recharge (MAR) in the form of Aquifer Storage and Recovery (ASR) systems are being applied for numerous water augmentation projects both in developed and developing countries. Given the onset of Climate Change and its influence on weather patterns and land use, it has been acknowledged the utilization of this technology will be ever increasing. This technique like all others does have its drawbacks or disadvantages, whereby to overcome these drawbacks or disadvantages it is recommended that logical planning process be followed. In this study, we developed a decision framework known as "Decision framework for the planning, designing, construction/testing and implementation of subsurface water storage system" to further standardize the planning and design process of subsurface water storage system to increase the probability of having a successful ASR/ASTR project. The formulation of this framework was based on earlier frameworks, guidelines, published papers and technical reports which were compiled into a data collection database. The database of which consider both qualitative and quantitative aspect for example recharge objectives, site location, water chemistry of the native, source and recovered water, aquifer characteristics(hydraulic conductivity, transmissivity, porosity), injection/pumping rate, ecological constraints, societal restrictions, regulatory restrictions etc. The assimilation of these factors into a singular framework will benefit the broad spectrum of stakeholder as it maps the chronological order under which ASR project should be undertaken highlighting at each stage the feasibility of the project. The final stage of which should result in fully operational ASR system. The framework was applied to two case studies and through the application of a modified ASR site selection suitability index (Brown et al., 2005) a score was derived to identify the performance of each site. A high score of which meant a maximize chance of success given the reduce presence of project constraints.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.556-560
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• 2009

개별 대수층에 냉수와 온수를 저장하여 수자원과 냉난방 열원으로 활용하는 방안에 대한 평가를 지열-지하수 부정류 모델링을 통해 수행하였다. 저장 및 회수 가동 시간이 증가함에 따라서 각각의 대수층 내에 온열과 냉열이 축열되는 현상이 확인되었으며, 지하수 유동에 의해 축열된 수체가 지하수 흐름방향으로 이동하는 현상을 확인 하여 지하수 유동이 축열 정도를 결정하는 요인이 될 수 있음을 확인하였다. 설정된 모델에 대하여, 두 개의 개별 대수층 사이의 열 간섭은 거의 없는 것으로 나타났다. 주입과 양수의 가동 횟수가 증가되면, 대수층 축열 효과는 증대되는 것으로 나타났다. 열-지하수 모델링을 통한 온도 예측은 실제 냉난방의 효율성을 결정짓는 수온을 정량적으로 계산할 수 있는 유용한 기술로 평가됨과 더불어, 수자원의 지하 저장을 통해 효율적으로 물을 확보하고 관리할 수 있는 방안이 될 수 있을 것으로 기대된다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.267-271
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• 2003

대수층 저장 및 회수(Aquifer Storage and Recovery, 이하 ASR) 기법은 지표수가 여유가 있는 기간동안 지하 대수층에 정수된 물을 주입하여 두었다가, 첨두 수요(peak demand)가 필요한 한시적인 기간동안 대수층 내에 저장되어 있던 물을 양수하여 공급하는 새로운 개념의 수자원 공급 체계의 일환이다. 본 발표에서는 미국 Oregon 주의 대표적인 3개 도시에서 수행된 수자원 공급 사업과 이 수자원 공급사업에서 ASR 기법이 어떻게 적용되었는지를 살펴보았다. 이들 도시에서 수행된 ASR 기법을 활용한 수자원 공급은, 기존 지표 저류조 저장 방식에 비해 월등히 경제적이며, 다양한 이점을 가지고 있는 것으로 드러났다. 또한 이들 도시에서의 ASR 기법 적용에 따른 효율성이 2001년도 및 2002년도에 분명하게 나타나 현재 이들 도시는 ASR 시설에 대한 확충 계획을 수립, 진행하고 있다. 한편, 이들 지역의 ASR 기법 활용 용수 공급 사례는, 국내의 경우에도 투수성이 우수한 화산암 지역, 제3기 지층 및 석회암 지역 등에서 활용될 경우, 충분한 효과를 발휘 할 수 있을 것으로 기대된다.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.3
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• pp.337-345
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• 2015

Two step rapid filter system as a pre-treatment for the injected water into aquifer storage and recovery (ASR) in Korea was developed to reduce physical blockage and secure the volume of the injected water. First, single rapid sand filters with three different media sizes (0.4~0.7, 0.7~1.0 and 1.0~1.4 mm) were tested. Only two sizes (0.4~0.7 and 0.7~1.0 mm) satisfied target turbidity, below 1.0 NTU. However, they showed the fast head loss. To prevent the fast head loss and secure the volume of the injected water, a rapid anthracite filter with roughing media size (2.0~3.4 mm) were installed before a single rapid sand filter. As results, both the target turbidity and reduction of head loss were achieved. It was determined that the media size for a rapid sand filter in two step rapid filter system (i.e. a rapid anthracite filter before a rapid sand filter) was 0.7~1.0 mm. In addition, the effects of coagulant doses on the removal of natural organic matter (NOM), which might cause a biological clogging, were preliminarily evaluated, and the values of $UV_{254}$, dissolved organic carbon (DOC) and SUVA were interpreted.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.3
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• pp.611-619
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• 2017

This paper intends to develop unit water production cost (UWPC) between alternative water resources including desalination, freshwater reservoirs, single-purpose dams, underground dams, and two indirect water in-take technologies - riverbank filtration and aquifer storage and recovery (ASR). The UWPCs of water supply schemes including each alternative are determined based on project cost, and operation and maintenance estimation models, which were developed based on real project cost data. The sensitivity analysis of UWPCs reveals that ASR is the lowest cost option in producing drinkable water among the alternatives, followed by riverbank filtration and underground dam. It is expected that economics related to the finding plays a critical role in supporting water resources planning and budget allocation for central and local water authority in Korea.