• Journal of The Korean Society of Agricultural Engineers
• /
• v.60 no.3
• /
• pp.113-121
• /
• 2018

The objectives of the research were 1) to develop the low-cost and high efficient desalination system to treat brackish water having high salt contents for irrigation at greenhouses near coast, and 2) to monitor and assess the effects of the brackish water desalination system on soil environment and growth in squash greenhouse cultivation area. The monitoring site was one of the squash greenhouse cultivation farm at Choengam-ri, Jinsang-myun, Gwangyang-si, Jeonnam-Do Monitoring results for groundwater irrigation water quality, and salinity showed a remarkable difference between control and treatment group. The salinity of soil at treatment group was less than at control group. While, the system made possible to increase the squash quantity from 4.7 ea to 6.3 ea at each and the average weight of the harvested squash was increased from 277.2 g to 295.1 g. The applied brackish water desalination system may be appled to reclaim sea or brackish irrigated area as alternative water resources, although long-term monitoring is needed to get more representative results at different level of salinity.

• Journal of Korean Society of Water and Wastewater
• /
• v.34 no.1
• /
• pp.53-60
• /
• 2020

Due to global climate change, Korea is experiencing flooding and drought severely. It is hard to manage water resources because intensive precipitation during short periods and drought are commonly occurred in Korea, recently. Severe drought occurred in 2015 and 2017 in the islands, and coastal and inland areas in Korea, and the citizens experienced decreased water supply and emergency water service by using bottled water. Therefore, the Korean government provided additional governmental funds such as the grant of drought disaster. In this study, we tried to calculate the cost of water for drought response based on the cost of tap water for the regional local governments in Korea and the grant of drought disaster by the Ministry of the Interior and Safety in Korea, etc. The estimated costs of water for drought responses in coastal and inland areas which have a chance to apply alternative water sources such as brackish or seawater desalination and water reuse in Korea were higher than in other areas in Korea. Additionally, as the novel approach of drought response, the 300 ㎥/day-scale desalination vessel was suggested to provide desalinated water for the islands in Korea. The estimated expenses of water supply for the target island areas (Sinan-gun and Jindo-gun) by the desalination vessel was lower than those by emergency water service by using bottled water.

• Journal of Korean Society of Water and Wastewater
• /
• v.30 no.6
• /
• pp.635-643
• /
• 2016

Gas hydrate (GH)-based desalination process have a potential as a novel unit desalination process. GHs are nonstoichiometric crystalline inclusion compounds formed at low temperature and a high pressure condition by water and a number of guest gas molecules. After formation, pure GHs are separated from the remaining concentrated seawater and they are dissociated into guest gas and pure water in a low temperature and a high pressure condition. The condition of GH formation is different depending on the type of guest gas. This is the reason why the guest gas is a key to success of GH desalination process. The salt rejection of GH based desalination process appeared 60.5-93%, post treatment process is needed to finally meet the product water quality. This study adopted reverse osmosis (RO) as a post treatment. However, the test about gas rejection by RO process have to be performed because the guest gas will be dissolved in a GH product (RO feed). In this research, removal potential of dissolved gas by RO process is performed using lab-scale RO system and GC/MS analysis. The relation between RO membrane characteristics and gas removal rate were analyzed based on the GC/MS measurement.

• Journal of Advanced Marine Engineering and Technology
• /
• v.22 no.5
• /
• pp.680-686
• /
• 1998

In the adoption of a desalination system the most important factor is the cost of fresh water pro-duction. 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 it is transformed to a high pressure gaseous state. During this process a huge amount of cold energy accumulated in cooling LNG is wasted. This wasted cold energycan be utilized to produce fresh water by using a sea water freez-ing desalination system. in order to develop a sea water freezing desalination system and to estab-lish 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 mechanisms of sea water in a cooled circular tube to measure the freezing rate and to investigate the freezing heat-transfer characteristics. The experimental results provide a general understanding of sea water freezing behavior in a cooled circular tube.

• Nuclear Engineering and Technology
• /
• v.55 no.2
• /
• pp.674-680
• /
• 2023

The brine and seawater are important and largely untapped sources of critical trace metals and elements. The coupling of selective recovery of trace metals from seawater/brine with desalination plants gives an added advantage of energy credits to desalination plants and as well as reduce the cost of desalinated water. In this paper, status review on recovery of important trace metals and other alkali metals from seawater is presented. The potential of Indian desalination plants for recovery of trace metals, based on recovery ratio of 0.35 is also highlighted. Studies carried out by the process based on adsorption using Radiation Induced Grafted (RIG) polymeric adsorbents and then fractional elutions are presented. The fouling factors due to bio fouling and dirt fouling have been estimated for various locations of interest through field trails. The pay loader in the form of compact Contactor Assembly with minimum pressure drop, for loading specially designed radiation grafted sorbent in leaflet form has been briefed, as required for plant scale facility. The typical conceptual process design details of farm assembly of project CRUDE are described.

• Journal of Korean Society of Environmental Engineers
• /
• v.30 no.12
• /
• pp.1197-1202
• /
• 2008

• Journal of Advanced Marine Engineering and Technology
• /
• v.22 no.4
• /
• pp.529-537
• /
• 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.

• Journal of Korean Society of Water and Wastewater
• /
• v.32 no.4
• /
• pp.301-307
• /
• 2018

Membrane distillation (MD) is a thermally driven desalination process with a hydrophobic membrane. MD process has been known to have a lower fouling potential compared to other pressure-based membrane desalination process (NF, RO). However, membrane fouling also occurs in MD process. In this study, the membrane fouling was observed in MD process according to the pre-treatment processes. The filtration and precipitation processes were applied as the pre-treatment to prevent the membrane fouling. The pore sizes of roughing filters were 0.4, 5, 10, 30, and $60{\mu}m$. The concentration of the coagulant was 1.2 mg/L as $FeCl_3$. The membrane fouling on MD membrane was successfully removed with both pre-treatment processes.

• Transactions of the KSME C: Technology and Education
• /
• v.2 no.1
• /
• pp.47-55
• /
• 2014

A new concept of an Eco-friendly desalination method is introduced in this study. The main idea of the desalination method of seawater is the condensation of the vaporized seawater by solar heat energy on the surface of seashore. The wind turbine blade plays a role of heat exchanger condensing the vaporized water in the air. In this analytical study, the availability of the proposed desalination system was studied. First, an analytical condensation theory of the vaporized water in air was arranged and the parametric study was conducted to estimate the amount of freshwater produced from the system with the change of the temperature difference between the humid air and turbine blade, and the relative humidity in air, and wind speed. From the analytical calculation, 2,927(ton/year) of freshwater was produced at the vertical-type wind turbine (Diameter=4m, Height=3m) as the relative humidity is 100%, the temperature difference between the impeller blade and the humid air is $40^{\circ}C$ and the wind speed is 10m/s.

• Journal of Korean Society on Water Environment
• /
• v.38 no.3
• /
• pp.143-149
• /
• 2022

Membrane distillation (MD) has emerged as a sustainable desalination technology to solve the water and energy problems faced by the modern society. In particular, the surface wetting properties of the membrane have been recognized as a key parameter to determine the performance of the MD system. In this study, a novel surface modification technique was developed to induce a Janus-type hydrophilic/hydrophobic layer on the membrane surface. The hydrophilic layer was created on a porous PVDF membrane by vapor phase polymerization of the pyrrole monomer, forming a thin coating of polypyrrole on the membrane walls. A rigid polymeric coating layer was created without compromising the membrane porosity. The hydrophilic coating was then followed by the in-situ growth of siloxane nanoparticles, where the condensation of organosilane provided quick loading of hydrophobic layers on the membrane surface. The composite layers of dual coatings allowed systematic control of the surface wettability of porous membranes. By the virtue of the photothermal property of the hydrophilic polypyrrole layer, the desalination performance of the coated membrane was tested in a solar MD system. The wetting properties of the dual-layer were further evaluated in a direct-contact MD module, exploring the potential of the Janus membrane structure for effective and low-energy desalination.