• Journal of Korean Society of Water and Wastewater
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• v.31 no.4
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• pp.339-346
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• 2017

In this study, thermal performance test of VMD module was performed, prior to the construction of the demonstration plant using the vacuum membrane distillation (VMD) module of the capacity of $400m^3/day$ and to the commercialization of the VMD module. For the thermal performance test, the experimental equipment of capacity of $2m^3/day$ was constructed. The permeate flux test and thermal performance test according to feed water conditions such as temperature and flow rate were conducted. The VMD module used in the study was manufactured by ECONITY Co., LTD with PVDF hollow fiber membrane. As a result, the Performance Ratio (PR) of the VMD module showed the maximum value of 0.904 under the condition of feed water temperature of $75^{\circ}C$ and flow rate of $8m^3/h$. PR value of the VMD module using PVDF hollow fiber membrane showed linearly increasing relationship with feed water temperature and flow rate. Also, The permeate flux of the VMD module was analyzed to have maximum value of 18.25 LMH and the salt rejection was 99.99%.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.358-363
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• 1999

This study was conducted to evaluate the extraction methods for the determination of antioxidants in soybean oil. Recovery rates of various antioxidants in soybean oil showed similar rates as 80.4~102.1% by solvent/solvent extraction method and 89.9~106.4% by sweep co-distillation method except 46.6~61.2% of PG at corresponding spiked concentractions. The maximun recovery rates of antioxidnts were obtained when extraction time and extraction temperature used in UNITREX were 20min and 21$0^{\circ}C$ respectively. In the recovery rates with the activation of florisil when 2% ofwater was added to florisil the highest recovery rates for TBHQ, BHA, BHT were obtained by sweep co-distillation met-hod. Therefore sweep co-distillation method showed less solvent simple operation and high recovery rate compared with solvent/solvent extraction method.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.582-582
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• 2018

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.1
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• pp.65-70
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• 2010

The distillation rate on LiCl-KCl eutectic salt under different vacuums from 0.5-50 mmHg was first investigated by using both a non-isothermal and a isothermal thermogravimetric (TG) analysis. Based on the non-isothermal TG data, distillation rate equations as a function of the temperature could be derived. Calculated flux by these model flux equations was in agreement with the distillation rate obtained from isothermal TG analysis. A distillation rate of $10^{-4}-10^{-5}$ mole $cm^{-2}sec^{-1}$ is obtainable at temperatures less than 1300K and vacuums of 0.5-50 mmHg. About a 99% salt distillation efficiency was obtained after an hour at a temperature above 1150 K under 50 mmHg in a small scale distillation test system. An increase in the vaporizing surface area is relatively effective for removing residual salt in the remaining particles, when compared to that for the vaporizing time. Over 99.95% of total distillation efficiency was obtained for a 1-h distillation operation by increasing the inner surface area from $4.52cm^2$ to $12.56cm^2$.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.4
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• pp.303-309
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• 2010

For the pyrochemical process of spent nuclear fuels, recovery of LiCl-KCl eutectic salts is needed to reduce radioactive waste volume and to recycle resource materials. This paper is about recovery of residual LiCl-KCl eutectic salts in radioactive rare earth precipitates (rare earth oxychlorides or oxides) by using a vacuum distillation process. In the vacuum distillation test apparatus, the salts in the rare earth precipitates were vaporized and were separated effectively. The separated salts were deposited in three positions of the vacuum distillation test apparatus or were collected in the filter and it is difficult to recover them. To resolve the problem, a vacuum distillation and condensation system, which is subjected to the force of a temperature gradient at a reduced pressure, was developed. In a preliminary test of the vacuum distillation/condensation recovery system, it was confirmed that it was possible to condense the vaporized salts only in the salt collector and to recover the condensed salts from the salt collector easily.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.140-145
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• 2015

This study was aimed at analyzing NOx conversion characteristics in the HC-SCR with biodiesel content changes of the secondary fuel injection (BD0, BD10, BD25). Test conditions for temperature were set to $290^{\circ}C$, $320^{\circ}C$ and $350^{\circ}C$ considering the upstream temperature of a HC-SCR, distillation of the secondary injected fuels and etc. The amount of fuel injection was adjusted with a fixed space velocity of 55,000(1/h). According to the test results of distillation, the T90 was the same level about $350^{\circ}C$ on all test fuels and the amount of evaporation was reduced at lower than $350^{\circ}C$ temperature condition with increasing biodiesel content. As biodiesel content which is mixed with the secondary injected fuel is increased, NOx reduction efficiency was determined to decrease. The difference of the Nox reduction ratio in a high temperature condition($320^{\circ}C$ and $350^{\circ}C$) than the low temperature($290^{\circ}C$) was more significant. These results are thought to be poor evaporation properties (distillation) and high molecular weight of the biodiesel.

• Membrane and Water Treatment
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• v.10 no.4
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• pp.251-257
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• 2019

Fabricating hydrophobic porous membrane is important for exploring the applications of membrane distillation (MD). In the present paper, poly(vinylidene fluoride) (PVDF) hollow fiber membrane was modified by coating polydimethylsiloxane (PDMS) on its surface. The effects of PDMS concentration, cross-linking temperature and cross-linking time on the performance of the composite membranes in a vacuum membrane distillation (VMD) process were investigated. It was found that the hydrophobicity and the VMD performance of the PVDF hollow fiber membrane were obviously improved by coating PDMS. The optimal PDMS concentration, cross-linking temperature and cross-linking time were 0.5 wt%, $80^{\circ}C$, and 9 hr, respectively.

• Journal of the Korean Solar Energy Society
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• v.34 no.5
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• pp.23-31
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• 2014

This study was accomplished to get the foundation design data of VMD(Vacuum Membrane Distillation) system for Solar Thermal VMD plant. VMD experiment was designed to evaluate thermal performance of VMD using PVDF(polyvinylidene fluoride) hollow fiber hydrophobic membranes. The total membrane surface area in a VMD module is $5.3m^2$. Experimental equipments to evaluate VMD system consists of various parts such as VMD module, heat exchanger, heater, storage tank, pump, flow meter, micro filter. The experimental conditions to evaluate VMD module were salt concentration, temperature, flow rate of feed sea water. Salt concentration of feed water were used by aqueous NaCl solutions of 25g/l, 35g/l and 45g/l concentration. As a result, increase in permeate flux of VMD module is due to the increasing feed water temperature and feed water flow rate. Also, decrease in permeate flux of VMD module is due to increasing salinity of feed water. VMD module required about 590 kWh/day of heating energy to produce $1m^3/day$ of fresh water.

• Food Science and Preservation
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• v.13 no.5
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• pp.623-628
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• 2006

This study was performed to develop extract materials from Elsholtzia splendens by analyzing the functionality and aroma profile by the simultaneous steam distillation extraction. The qualities of extracts such as total yield, total phenolic compound and electron donation ability were affected by extraction temperature than time. The main flavor compounds were analyzed as estragole, thymol and beta-caryophyllene. The response variables had significant with extraction temperature than tim. The established model was suitable to predict calculated value in experimental ranges. The optimum extinction conditions, which were limited of maximum value for dependent variables were $108^{\circ}C$ and 2.1 hr in the simultaneous steam distillation extraction method.

• Membrane Journal
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• v.13 no.3
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• pp.154-161
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• 2003

We measured the permeation characteristics of water with the hydrophobic PTFE membranes dependent on water temperature to confirm the separation of oxygen isotopes using Air Gap Membrane Distillation (AGMD) and Vacuum Enhanced Membrane Distillation (VEMD). Isotopic concentrations of $H_2^{16}O$ and $H_2^{18}O$ of the permeated water vapor were measured by Diode Laser Absorption Spectroscopy. Concentrations of the heavy oxygen isotopes in the permeated water vapor were decreased. Isotope separation coefficients for the hydrophobic PTFE membranes were 1.004∼1.01 depending on the experimental conditions. We observed the effects of air in membrane pores on the oxygen isotope separation. Isotope separation coefficients for the hydrophobic PTFE membranes without air in pores are higher than those for the membrane with air in pores.