• Journal of Korean Society of Water and Wastewater
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• v.24 no.2
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• pp.135-139
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• 2010

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1432-1440
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• 2015

A dynamic economic dispatch and control method is proposed to minimize the overall generating cost for a stand-alone microgrid in DongAo Island, which is integrated with wind turbine generator, solar PV, diesel generator, battery storage, the seawater desalination system and the conventional loads. A new dispatching strategy is presented based on the ranking of component generation costs and two different control modes, in which diesel generator and battery storage alternate to act as the master power source to follow system power fluctuation. The optimal models and GA-based optimization process are given to minimize the overall system generating cost subject to the corresponding constraints and the proposed dispatch strategy. The effectiveness of the proposed method is verified in the stand-alone microgrid in DongAo Island, and the results provide a feasible theoretical and technical basis for optimal energy management and operation control of stand-alone microgrid.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.6
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• pp.437-446
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• 2019

Reverse osmosis seawater desalination facilities can extend the cleaning cycle and replacement time of the reverse osmosis membrane by pretreatment process. Selection of pretreatment process depends on water quality. It was attempted in this study to select approriate pretreatment process for the Masan bay, which was high in particles and organic content. For this purpose, performances of pretreatment processes such as filter adsorber (FA), pore controllable fiber (PCF), and ultrafiltration (UF) were compared based on the silt density index (SDI). The SDI value of the filtrate should be less than 3. The study results showed that UF can produce the filtrate quality satisfying the requirement. However, the transmembrane pressure (TMP) of UF increased quickly, reaching 0.6 bar within 4 days. In order to secure stable operation, FA and PCF were combined with UF. The study results showed that combination of PCF and UF was able to extend the filtration duration (more than 2 months) until to reach TMP of 0.6 bar.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.2053-2058
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• 2004

The pressurized light water cooled, medium power (330 MWt) SMART (System-integrated Modular Advanced ReacTor) has been under development at KAERI for a dual purpose : seawater desalination and electricity generation. The SMART design verification phase was followed to conduct various separate effects tests and comprehensive integral effect tests. The high temperature / high pressure thermal-hydraulic test facility, VISTA(Experimental Verification by Integral Simulation of Transient and Accidents) has been constructed to simulate the SMART-P (the one fifth scaled pilot plant) by KAERI. Experimental tests have been performed to investigate the thermal-hydraulic dynamic characteristics of the primary and the secondary systems. Heat transfer characteristics and natural circulation performance of the PRHRS (Passive Residual Heat Removal System) of SMART-P were also investigated using the VISTA facility. The coolant flows steadily in the natural circulation loop which is composed of the steam generator (SG) primary side, the secondary system, and the PRHRS. The heat transfers through the PRHRS heat exchanger and ECT are sufficient enough to enable the natural circulation of the coolant.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.201-201
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• 2019

세계적인 기상이변으로 가뭄발생 빈도 및 영향이 증가하고 있으며, 급속한 산업화로 사용 가능한 수자원이 점차 고갈되어 있어, 국내에서도 해수담수화(Seawater Desalination)는 새로운 대체수자원으로 많은 관심을 받고 있다. 해수담수에 필요한 에너지 약 50~70%는 역삼투(Reverse Osmosis) 공정에서 발생되며, 해수온도 및 염분도에 따라 많이 변동될 수 있으므로 국립해양조사원(KHOA)의 과거 20년 자료를 이용하여 해수담수화 시설물 위치에 따른 영향을 분석하였다. 해수담수화에 필요한 에너지는 막 제조사에서 제공하는 RO Projection Software를 적용하여 에너지 소모량을 평가하고, 이를 고려한 시설물 위치에 대한 평가 모델을 구축하였다. 기존 해수담수화 시설은 대규모 물 공급이 필요한 지역을 우선적으로 고려했기 때문에 시설물 위치에 대한 객관적인 평가기준 마련이 어려웠다. 그러나 해수담수화 플랜트는 한번 설치되면 장기적인 시설물 유지 및 관리가 필요함으로 경제성을 고려한 최적 입지의 선정은 매우 중요하다. 본 연구는 국립해양조사원의 수집된 자료를 바탕으로 해수담수화 시설물 입지선정을 정량적으로 평가함으로서, 시설물 위치에 대한 의사결정시 참고할 수 있는 기초자료로 활용될 것으로 기대한다.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.3
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• pp.337-342
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• 2008

A population growth and industry advances are increasing the demand for water while improving the quality of life. By turning seawater into freshwater it is an alternative for the water shortage problem. The study analyzes the orders and makes suggestions on the outlook of an enterprise that can supply desalination plants both inside and outside the country. It compares the production capacity of enterprises in the desalination industry who deal with the thermal and RO methods. We compare 7 enterprises in the thermal method which includes Doosan Heavy Industries, and the top 10 enterprises in the RO method which includes General Electric Corp. Now that the markets in the Middle East have opened and markets in other regions are gradually growing, demand for water will grow especially in developing countries that are in the process of industrialization. Also, the market share of thermal method desalination has been falling, gradually, because too much energy is spent during the process. On the other hand, the market share of the RO method will rise from 37% in 2005 to 57% in 2015. Recently, the desalination market shows that changing from thermal method to RO method is the trend in the Middle East. Growth and demand in other regions are growing at the same pace as the Middle East. Due to this trend, if the RO system, which is highly effective and uses less energy, were to be continuously developed it would be possible to supply water using sea water and would be a viable alternative water resource.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.410-419
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• 2017

Since the beginning of the water shortage by disasters such as global warming, environmental pollution, and drought, development of original technology and studies have been undergone to increase availability of water resources. Among them the water treatment separation membrane technology is an environmentally friendly process that does not use chemicals and shows better water quality improvement effect than conventional physicochemical and biological processes. The water treatment membrane can be applied to various fields such as waste water treatment, water purification treatment, seawater desalination, ion exchange process, ultrapure water production, organic solvent separation and water treatment technology, and it tends to expand the range of application. In the core technology of water treatment membrane, researches are being actively carried out to develop a separation membrane of better performance by controlling the pore size to adjust the separation performance. In this review, we summarized the frequency of announcement by country and organization through the technological competitiveness evaluation of patents and papers of the water separation membrane. Also, we evaluated the results from membrane research for waste water treatment, water purification treatment, seawater desalination, ion exchange process and present the future direction of research.

• Membrane Journal
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• v.29 no.6
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• pp.314-322
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• 2019

A worsened drought in Chungnam province of Korea due to climate change and increasing water demand at Daesan industrial complex have motivated the 100,000 ㎥/d seawater desalination project. In this study, therefore, the comprehensive analysis of parameters affecting the reverse osmosis (RO) performance was conducted. Under the various conditions of feedwater salinity and temperature in Daesan, energy consumption was calculated as 2.39 ± 0.13 kWh/㎥. The decrease in membrane flux and recovery rate positively impacted annual operation cost. The average total dissolved solids (TDS) of the permeate and energy consumption with highly permeable membrane according to the membrane manufacturer were 3.84 mg/L and 2.22 ± 0.13 kWh/㎥, respectively. In addition, energy saving up to 0.29 kWh/㎥ or cost reduction of membrane module up to 15.6% is expected by changing the RO configuration from full two pass to partial or split partial two pass.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.3
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• pp.271-278
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• 2016

Recently, reverse osmosis (RO) is the most common process for seawater desalination. A common problem in both RO and thermal processes is the high energy requirements for seawater desalination. The one energy saving method when utilizing the osmotic power is utilizing pressure retarded osmosis (PRO) process. The PRO process can be used to operate hydro turbines for electrical power production or can be used directly to supplement the energy required for RO desalination system. This study was carried out to evaluate the performance of both single-stage PRO process and two-stage PRO process using RO concentrate for a draw solution and RO permeate for a feed solution. The major results, were found that increase of the draw and feed solution flowrate lead to increase of the production of power density and water permeate. Also, comparison between CDCF and CDDF configuration showed that the CDDF was better than CDCF for stable operation of PRO process. In addition, power density of two-stage PRO was lower than the one of single-stage. However, net power of two-stage PRO was higher than the one of single-stage PRO.

• Membrane Journal
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• v.30 no.3
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• pp.190-199
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• 2020

The utilization of multiple water sources becomes important due to the master plan for development of water supply released by Ministry of Environment, Korea in 2018. In this study, therefore, the analysis of comprehensive effect in blending applicable water sources in Daesan where 100,000 ㎥/d seawater desalination plant will be constructed for industrial use was performed. The increase in mixing ratio of other water sources with seawater reduced salinity up to 50%, but negatively impacted the turbid and organic matter. Lab-scale reverse osmosis performance test also found that membrane fouling was exacerbated in blended water condition. The simulation results of reverse osmosis indicated 39% energy saving on average is expected at the one-to-one blending ratio, however, long-term performance test at the pilot-scale plant is highly required to evaluate the inclusive impact of mixing seawater and other water sources.