• Membrane Journal
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• v.18 no.1
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• pp.65-74
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• 2008

NOM and fine particles are the main target materials in water treatment using membranes. Particularly, humic substances extracted from soils are frequently used in many fundamental studies representing natural organic matter in raw water for drinking water treatment. In this study, ultrafiltration (UF) of artificial humic water and natural river water was conducted and the characteristics of removal efficiency and permeability were compared. In the UF of river water, the transmembrane pressure increased in the same pattern with that of 5 mg/L humic water. For the removal of organic matter and fine particles, however, two types of feed water had shown different trends. Kaolin particles and humic acids added to artificial water were better removed, while colloids and organics in natural water were relatively poorly removed. From the $UV_{254}$ and GPC analyses, it seemed that the hydrophobicity and size of humic substances contributed to the greater removal of organic matter. The UF membrane applied for humic water also showed a higher flux recovery by caustic chemical cleaning than that for river water.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.458-464
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• 1999

The value of lysozyme as a natural food preservative is continuously increased due to its unique antimicrobial activity. To determine the optimum separation concentration among the various hen egg white protein (HEWP) concentrations (0.25, 0.5, 1.0, w/v), protein concentrations, lysozyme concentrations, specific activities (SA), and purification factors of prefiltered solution (PFS) and PM30 permeate solution (PMS) were compared. The purity of lysozyme separated at each step was analyzed and confirmed by gel permeation chromatography and electrophoresis. The fouling deposits on membrane were observed by SEM. The non-enzymatic proteins were removed over 99% by ultrafiltration (UF). The increased feed concentration did not contribute to the increase of SA. SA of PMS was 18 to 31 times higher than that of PFS. The optimum feed concentration was decided as 0.25% based on SA and purification factor. The non-enzymatic region of gel chromatogram was proved to be ovalbumin. The thickness of deposit on the UF membrane was approximately $0.9{\mu}m$ and removed by cleaning with 0.1 N NaOH. Therefore, UF using PM30 membrane was very effective to separate the antimicrobial lysozyme from various HEWPs.

• Journal of Hydrogen and New Energy
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• v.16 no.1
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• pp.82-91
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• 2005

Polymer membrane needs to maintain appropriate moisture. Insufficient moisture causes low conduction of hydrogen ion because of increased contact resistance between electrode and membrane by shrinking membrane, and abundant moisture decreases fuel cell performance as difficulty of diffusion reacting gas. Therefore, water controlling system is very consequential for the polymer membrane fuel cell. If hollow fiber membrane humidification is used between fuel and air lines, it is possible to supply heat to fuel and air by using thermal exchanger. It can supply appropriate humidity depending on operating temperature, and can recover heat from exhaust gas which contains water vapor and air. Because of simple structure of humidification system, this system can be easily applied in the PEMFC and cut down cost.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.2
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• pp.267-274
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• 2008

This study is about efficiency of pretreatment process and operating factor to membrane process at continuous coagulation/ultrafiltration process in water treatment. The capacity of pilot plant was $0.06{\beta}(C)/d$. The raw water used was from Nakdong stream which was characteristized by high organic matter and high turbidity. The result of the test was that coagulation is good process as to high removal rate to organic matter and turbidity but It caused problem to membrane pore blocking. This paper is to determine the membrane fouling potential under different membrane flux, backwash pressure and linear velocity. Backwash pressure and flux is important parameter on operation of membrane system. Those are directly affected on membrane system. When backwash pressure increased from 150 kPa to 200 kPa, the result showed that fouling (pressure increase rate) changed from 3.69 kPa/h to 0.93 kPa/h and the recovery rate changed from 90.7 % to 82.0 %. Linear velocity had slightly effect on fouling. Linear velocity increased from 0.2 m/s to 0.5 m/s, the corresponding pressure rate changed from 0.93 kPa/d to 0.77 kPa/d.

• Membrane Journal
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• v.6 no.3
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• pp.182-187
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• 1996

Hydrophilic poly(acrylonitrile) [PAN] membrane with good molecular weight cut-off characteristics were prepared by using the phase inversion method. Permeability and molecular weight cut-off of the membranes were measured through the ultrafiltration test. On the surface of the PAN support membranes, poly(acrylic acid) [PAA] was deposited by dip-coating. The water permeability of the PAN support membrane had $0.17~31\textrm{mm}^3/m^{2} \cdot s \cdot Pa$, the molecular weight cut-off 42, 000~150, 000. The transport characteristics of the prepared composite membranes were significantly affected by the variation of the support membrane mophology. The permeability of the composite membrane was decreased with increasing molecular weight cut-off of the support membrane, and the separation factor was slightly changed depending on the feed concentration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.4
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• pp.865-871
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• 2009

Chondroitin sulfate was extracted by alkali method and enzyme method from shark cartilage. In extract system, various processing parameters such as concentration of alkali and alcarase, temperature etc, have been investigated for optimization condition. The pure chondroitin sulfate was obtained by UF membrane separation. The characteristics was also investigated with gel permeation chromatograpy(GPC). The molecular weight of chondroitin sulfate was $2.7\times10^4$ Da.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1998.10a
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• pp.134-137
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• 1998

표면처리 한 UF 막으로 오일/물 에멀젼과 오일-SDS/물 어멜젼을 한외여과 시험하였다. 고분자와 계면활성제를 polysulfon막에 흡착시켜 표면을 처리하였다. 오일-SDS/물 에멀젼의 한외여과는 SDS양을 변화시키면서 수행하였다. 다양한 표면처리 한 막으로 한외여과 실험을 회분식 실험방법으로 수행하였다. 표면처리 안한 막에 대한 오일 에멀젼 한외여과시 fouling의 주요 원인이 오일 에멀젼의 흡착이며, 막의 표면처리와 오일 에멀젼에 계면활성제의 주입으로 뚜렷한 fouling의 저감효과가 있었다.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1146-1151
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• 1998

To prevent deterioration of the jujube wine quality by using heat sterilization while commercial production, ultrafiltration and microfiltration were applied. The permeate flux and physicochemical properties of jujube wine determined by MF and UF membrane ($0.2\;{\mu}m$ pore size and 50 K dalton cut off) were investigated. The permeate flux increasing caused the increased operating pressure. The Hunter L value of jujube wine treated MF and UF was increased and that of b value was decreased. The turbidity of jujube wine treated MF and UF was largely decreased. And the values of pH, ethanol, total acid and soluble solid were decreased or were at the same level comparing with untreated jujube wine. Retention percentage of sugar and organic acid was more than 80% and was not influenced by operating pressure. Results of sensory evaluation indicated that the color of UF was superior to un-treatment and commercial ones. And the flavor and taste were not significantly different with untreated jujube wine. The quality deterioration of commercial jujube wine could be improved by MF and UF. According to the sensory evaluation, there was also not difference between MF and UF for preference test. Therefore, the quality of jujube wine could be improved by MF having better separation yield efficiency than UF.

• Journal of Korean Society on Water Environment
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• v.18 no.4
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• pp.387-394
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• 2002

The efficiency variation of UF(tubular)/RO(spiral wound) process using acrylic wastewater treated by photo-catalyst pretreatment and coagulant-filter-neutralization pretreatment processes were discussed wit the variation of appled pressure and temperature. Ultrafiltration tubular module using acrylic wastewater treated by photo-catalyst pretreatment and coagulant-filter-neutralization pretreatment processes was shown that COD and T-N were not highly affected with the variation of appled pressure and temperature. It was shown that removal efficiency of COD and T-N was low. Removal efficiency of TDS and turbidity with ultrafiltration tubular module was better with the acrylic wastewater by photo-catalyst pretreatment than acrylic wastewater by coagulant-filter-neutralization pretreatment. T-N and TDS were shown high removal efficiency in reverse osmosis membrane process.

• Transactions of the KSME C: Technology and Education
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• v.1 no.1
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• pp.59-68
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• 2013

In the present study, sea water reverse osmosis desalination system was composed with an ultra-filtration membrane as a pre-treatment. Sea water was induced into the pre-treatment composed with an auto-screen filter and an ultra-filtration membrane. It was proved that the permeate of the pre-treatment was adequate for reverse osmosis desalination system by measuring the $SDI_{15}$ and the turbidity. Feed salinities was changed by mixing the brine and the permeate. Inlet salinities effected the performances of sea water reverse osmosis desalination system in a large amount such as the salt rejection, the recovery ratio, the pressure, the product salinity. Energy consumptions per the ton of the product were almost linearly increased with the inlet salinities.