• 한국농공학회논문집
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• 제57권3호
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• pp.87-92
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• 2015

Cultivation on reclaimed tidal land is often difficult in the problem such as high salinity of soil, bad drainage because of high level of groundwater. Many researches have been made efforts to solve these problems, but effect of improvement is low and practicality is insufficient. In this study, through numerical analysis of the transport properties of salt and water, we suggested underground drainage of the reclaimed land and the desalination promotion methods in the soil. The results of characteristic of desalination and seepage analysis of underdrain show that underdrain is able to increase twice of the underground seepage amount when installing perforated pipe with horizontal filter (width 50cm) more than installing only the perforated pipe. For soil which coefficient of permeability is below $1{\times}10^{-4}cm/s$ that desalination with pond water is not possible, a method to increase the permeability of the soil is necessary. Therefore, it was concluded that application of underdrain using perforated pipe with horizontal filter would be low-cost and practical.

• 상하수도학회지
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• 제12권3호
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• pp.48-54
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• 1998

Korea becomes one of the countries which suffer from water shortage. It is expected that its water shortage in the early 2000's will be more than 10% of the annual demand. The shortage problem is more serious in the coastal areas where many industry complex locate. To solve the shortage problem, seawater desalination gets more attention as an alternative water supply source since Korea is surrounded by sea on its three sides. For potential application of seawater desalination in Korea, an economic analysis was conducted using cost data for the plants in the Middle Ease areas, The United states and others. The study is to provide a basis for the government to establish a strategy for promoting seawater desalination in Korea. It is discussed that the Reverse Osmosis (RO) process gets cheaper over times than the thermal processes of Multi-stage Flash Distillation (MSF) and Multi Effect Distillation (ME), especially in case where the capacity is less than about 50,000 ton/day. The unit cost of RO seawater is analyzed about US$1.35/ton in 1990 price. Since the Desalination plant can be operated regardless of weather conditions, industries in Korea's coastal areas which suffer from frequent droughts and water shortages are recommended to look into this option with more attention.

• Membrane and Water Treatment
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• 제5권1호
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• pp.15-29
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• 2014

Reverse Osmosis (RO) desalination has gained wide and increasing acceptance around the world as a straightforward undertaking to alleviate the alarming water crisis. An enhanced monitoring of the quality of the water feeding in seawater RO (SWRO) plant through the application of an effective pretreatment option is one of the keys to the success of RO technology in desalination plants. Over the past 10 years, advances in ultrafiltration (UF) membrane technologies in application for water and wastewater treatment have prompted an impetus for using membrane pretreatment in seawater desalination plants. By integrating SWRO plant with UF pretreatment, the rate of membrane fouling can be significantly reduced and thus extend the life of RO membrane. With the growing importance and significant advances attained in UF pretreatment, this review presents an overview of UF pretreatment in SWRO plants. The advantages offered by UF as an alternative of pretreatment option are compared to the existing conventionally used technologies. The current progress made in the integration of SWRO with UF pretreatment is also highlighted. Finally, the recent advances pursued in UF technology is reviewed in order to provide an insight and hence path the way for the future development of this technology.

• Advances in Energy Research
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• 제4권2호
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• pp.147-161
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• 2016

To start with, finding a sustainable method to produce sweet water and electricity by using renewable energies is one of the most important issues at this time. So, experimental and theoretical analysis of the performance of a closed solar powered still, which is jointed to photovoltaic cells and vacuum pump and equipped by nano plate, as the principle stage of zero discharge desalination process is investigated in this project. Major goal of this work is to reuse the concentrated brine of the Mobin petrochemical complex in order to produce potable, sweet water from effluent saline wastewater and generating electricity in the same time by using solar energy instead of discharging them to the environment. It is observed the increase in brackish water temperature increases the average daily production of solar desalination still considerably. Therefore, the nano plate and vacuum pump are added to augment the evaporation rate. The insolation rate, evaporation rate, the average brackish temperature, ambient temperature, density are investigated during a year 2013. In addition to obtain the capacity of solar powered still, the highest and lowest amount of water and electricity generation are reported during a twelvemonth (2013). Results indicate the average daily production is increased 16%, which represents 7.78 kW.h energy saving comparing with traditional solar still.

• 대한기계학회논문집B
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• 제38권5호
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• pp.407-412
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• 2014

가스하이드레이트 원리를 이용한 신개념의 해수담수화 장치를 제안하였다. 본 연구의 연속식 장치는 하이드레이트를 제조하고, 듀얼실린더의 압축공정에 의해 해수로부터 순수의 하이드레이트 펠릿화가 가능하다. 해수 샘플로부터 용존된 각 이온들의 제거 효율이 유도결합플라즈마분광광도계(ICP-AES)와 이온크로마토그래피(IC)에 의해 분석되었다. 본 연구에서 제안된 방법과 장치를 이용한 해수담수화시 형성된 하이드레이트 결정과 고농도의 염농축액과의 분리에 어려움이 있지만, 이를 해결함으로 좀더 효율적인 해수담수화 공정 적용이 가능할 것으로 판단된다.

• 한국표면공학회지
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• 제40권1호
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• pp.44-56
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• 2007

Excavated archaeological iron artifacts are usually conducted the conservation treatment for removal of chloride ions in the corrosion products. However, some iron artifacts are corroded again even after the conservation treatment due to unremoved chloride ions. Therefore, it is important to prevent desalinized artifacts from the occurrence of corrosion after the treatment. In this paper, we investigated the characteristics of corrosion products on salinized iron artifacts and evaluated the variety of desalination methods such as autoclave, intensive washing and NaOH. It was also found that ${\beta}-FeOOH$ (Akaganeite) played an important role on the occurrence of corrosion and the treatment for removal of chloride ions. The extents of desalination were compared between the desalination methods. Results showed that the autoclave method represented the highest efficiency for desalination while the intensive washing method was the lowest.

• Journal of Advanced Marine Engineering and Technology
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• 제22권4호
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• pp.529-537
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• 1998

Currently as due to the rapid development of industry and increase in population we meet serious problems concerning the shortage and pollution of water. In the country many experts predict a shortage of water approaching 450 million tons by the year 2006. To cope with this serious problem it is necessary to construct desalination plants. In the adoption of a desalination system the most important factor is the cost of fresh water production,. In general LNG is stored in a tank as a liquid state below $-162^{\circ}C$. When it is serviced, however the LNG absorbs energy from a heat source and transforms to a high pressure gaseous state. During this process a huge amount of cold energy accumulated in cooling LNG is wasted. This wasted cold energy can be utilized to produce fresh water by using a sea water freezing desalination system. In order to develop a sea water freezing desalination system and to establish its design technique qualitative and quantitative data regarding the freezing behavior of sea water is required in advance, The goals of this study are to reveal the freezing behavior of sea water is required in advance. The goals of this study are to reveal the freezing mechanisms of sea water to measure the freezing rate and to investigate the freezing heat-transfer characteristics,. The experimental results will provide a general understanding of sea water freezing behavior in a rectangular vessel cooled from above.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권5호
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• pp.40-48
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• 2012

In this study, economic analysis of five desalination technologies for saline agricultural land was carried out. The analysis was comprehensively evaluated by calculating changes in crop production and benefit/cost (B/C) ratio. The analysis of crop production was in the order of tomato > cucumber > a (musk) melon > watermelon > cabbage, and economical efficiency for desalination technology was in the order of soil exchange > soil addition > electrokinetics > under-drainage > subsoil reversal. In cost benefit analysis, B/C ratio was in the order of under-drainage > soil exchange > electrokinetics > soil addition > subsoil reversal, and all desalination technologies used in this study have the ratio higher than 1, which means economical efficiency was high. Based on the net production considering B/C ratio, the general economic analysis was exactly order from that of crop production analysis. As a result, economical efficiency of soil exchange was highest, and economical efficiency of soil addition and electrokinetic was relatively higher than others.

• 한국가시화정보학회지
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• 제20권2호
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• pp.13-20
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• 2022

An effective capacitive deionization process termed membrane capacitive deionization (MCDI) is newly designed and experimentally tested for seawater desalination. By preventing co-ions to be expelled, MCDI can improve the ion removal performance, but there is a trade-off between blocking co-ion transfer and increasing contact resistance. The conventional MCDI uses 2D-shaped films which increase contact resistance and reduce desalination performance in the trade-off. In this paper, with the 3-D shape of Nafion coated activated carbon cloth, the mentioned problems are expected to be solved making the desalination performance better. We visualized ion concentration and fluid flows with half-MCDI cell that can measure only efficiency of cathode. We found the optimal number of coatings which have the better efficiency than CMX, commercial cation exchange membrane in fixed current conditions of 100uA.

• 공업화학
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• 제33권6호
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• pp.551-556
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• 2022

분리막을 활용한 수처리 공정을 통해 얻어진 담수된 물은 전 세계적인 물 부족 문제를 해결해 줄 수 있는 유망한 기술로 많은 주목을 받고 있다. 오늘날 담수화에 가장 널리 활용되고 있는 역삼투압 분리막 기반 공정은 지구상에 풍부한 바닷물을 담수화하는 기술이기 때문에 산업적으로도 그 잠재성이 매우 풍부하다. 이러한 담수 공정 성능을 향상시키기 위해서는 분리막의 역삼투압 메커니즘을 원자/분자 수준에서 이해할 필요가 있다. 본 총설에서는 오늘날 소재 연구에 있어 중요한 역할을 담당하고 있는 분자 전산모사에 대한 소개와 함께 역삼투압 분리막 연구 개발에 있어 원자/분자 수준에서의 전산모사 역할을 소개하고자 한다.