• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.1.2-1.2
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• 2011

Electrohydrodynamics is a good approach to produce uniform-sized colloids and fibers in a continuous process. The dimension can be controlled from tens of nanometers to a few micrometers. The structure of the colloids and nanofibers from electrohydrodynamics has been diversified according to the uses. Especially, core-shell structure and hybridization with functional nanomaterials are fascinating due to their possible uses in drug-delivery systems, multifunctional scaffolds, organic/inorganic hybrids with new functions, and highly sensitive gas- or bio-sensors. This talk will present the structural variations in the colloids and fibers by simply employing phase separation during electrohydrodynamic process and demonstrate their possible applications.

• 상하수도학회지
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• 제22권5호
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• pp.531-540
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• 2008

The main advantage of dissolved air flotation (DAF) in water treatment process is the small dimension compared with conventional gravity sedimentation and it can be basically reduced by the separation zone performed with the short solid-liquid separation time. Fine bubbles make such a short time possible to carry out solid from liquid separation as a collector on the course of water treatment. Therefore, the dimension of separation zone in DAF process is practically determined by the rise velocity of the bubble-floc agglomerates, which is a floc attached with several bubbles. To improve flotation velocity and particle removal efficiency in DAF process, many researchers have tried to attach bubbles as much as possible to flocs. Therefore, the maximum number of attached bubble on a floc and the rise velocity of bubble-floc agglomerates considered as the most important factor to design the separation zone of flotation tank in DAF process was simulated based on the population balance theory. According to the simulation results of this study, the size and volume concentration of bubble influenced on the possible number of attached bubble on a floc. The agglomerates attached with smaller bubble was more sensitive to hydraulic loading rate in the separation zone of DAF process. For the design of a high rate DAF process applied over surface loading 40 m/hr. it is required a precise further study on the variation of bubble property and behavior including in terms of bubble size distribution.

• Korean Membrane Journal
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• 제5권1호
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• pp.25-30
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• 2003

Chitosan membranes crosslinked with glutaraldehayde that contained chiral environment were prepared. The chitosan membranes were characterized using FTIR and swelling index measurements. Their swelling index in water ranged from 100 to 70%, depending on the crosslinking time. The separation of D- and L-isomers of tryptophan was achieved through a pressure driven membrane separation process, using the self-supporting crosslinked chitosan membranes. The chiral separation performance of the membranes depended strongly on the swelling index of the membranes and the separation conditions such as concentration of feed solutions and different operating pressures. Especially when a chitosan membrane with a swelling index of 70% was used, almost complete optical resolution of D- and L-tryptophan was obtained ; enantiomeric excess (ee %) of 97.92% and flux of 2.26 g/㎡$.$h.

• 한국초전도ㆍ저온공학회논문지
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• 제3권1호
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• pp.69-73
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• 2001

For developing the cryogenic air separation unit, it requires some technology such as basic process design. equipment design and manufacturing based on the cryogenic physical properties and separation theory. In this study, we developed a process and equipment for producing high purity nitrogen which has the production capacity of 1600N㎥/h under 1 ppm $O_2$ and $H_2O$. Also we found that the number of theoretical plate(NTP) of distillation column was 44 and maximum nitrogen recovery ration of this process was 42% from the process simulation. The performance test was also carried out for the nitrogen recovery ratio and equipment efficiency. The results showed that the optimum nitrogen recovery was 41% and the maximum equipment efficiency was attained.

• 한국초전도ㆍ저온공학회논문지
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• 제25권4호
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• pp.60-64
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• 2023

The manufacturing process of antibody drugs comprises two main stages: the upstream process for antibody cultivation and the downstream process for antibody extraction. The domestic bio industry has excellent technology for the upstream process. However, it relies on the technology of foreign countries to execute downstream process such as affinity chromatography. Furthermore, there are no domestic companies capable of producing the equipment for affinity chromatography. High gradient magnetic separation technology using a high temperature superconducting magnet as a novel antibody separation and purification technology is introduced to substitute for the traditional technology of affinity chromatography. A specially designed magnetic filter was equipped in the bore of the superconducting magnet enabling the continuous magnetic separation of nano-sized paramagnetic beads that can be used as affinity magnetic nano beads for antibodies. To optimize the magnetic filter that captures superparamagnetic nanoparticles effectively, various shapes and materials were examined for the magnetic filter. The result of magnetic separation experiments show that the maximum separation and recovery ratio of superparamagnetic nanoparticles are 99.2 %, and 99.07 %, respectively under magnetic field (3 T) and flow rate (600 litter/hr).

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권5호
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• pp.46-55
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• 2013

The main objective was to evaluate the efficiencies of different separation techniques, such as gravity separation, magnetic separation, and aerial separation. Zinc and cadmium removal efficiencies by gravity separation and magnetic separation were 28.3~29.3% and 19.1%, respectively, and were higher than the efficiency obtained by aerial separation. Results showed that the combination of gravity separation and magnetic separation in series which was to maximize the removal efficiencies gave removal efficiency of 21.5~38.7% for zinc and 22.1~23.4% for cadmium. The mass of soil meeting the regulation standards for zinc and cadmium after retrieval from the combined separation process accounted for approximately 80% of the treated soil that would be reusable without the pre-treatment procedure as the neutralization process using in the soil washing method. Physical separation techniques utilizing heavy metal properties are the alternative method to remediate heavy-metal contaminated soils in environmental and economic aspects.

• Korean Chemical Engineering Research
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• 제58권1호
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• pp.69-83
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• 2020

경질 올레핀은 중요한 석유화학제품일 뿐 아니라 다양한 화학 중간체들을 위한 기본 구성체이다. 최근 에틸렌이 생산 제품의 대부분을 차지하는 Ethane Cracking Center (ECC) 공정이 크게 늘어남에 따라 프로필렌 공급이 매년 꾸준히 증가하는 프로필렌 수요를 따라잡지 못하고 있다. 이에 따라 프로필렌의 수요를 따라잡기 위하여 메탄올로부터 올레핀으로 전환하는 기술이 보다 중요하게 되었다. Methanol to olefins (MTO) 공정은 합성가스를 통해 메탄올을 생산하고 메탄올로부터 프로필렌 등 올레핀을 생산한다. 메탄올을 올레핀으로 전환하는 반응은 사용되는 촉매에 따라 다른 반응생성물 조성을 갖기 때문에 생성물에 따른 적절한 분리 방법이 고려되어야 한다. 따라서 네 가지의 대표적인 반응 생성물 조성들에 대하여 네 가지의 분리공정 대안들을 Aspen plus를 이용하여 모사하였다. 또한 모사 결과를 바탕으로 기술적 경제적 분석을 통하여 MTO 공정의 반응 생성물 조성에 대한 각 분리공정의 성능을 평가하였으며, 이를 통해 MTO 공정의 반응기에서 생산되는 생성물 조성에 따라 적합한 분리공정 선정을 위한 지침을 제시하였다.

• 자원리싸이클링
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• 제28권3호
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• pp.21-25
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• 2019

The utilization of incineration ash from municipal waste must be promoted to solve the social problem on the shortage of final disposal site. In this research, metals should be recovered to avoid the damage of the crushing machine during the utilization of incineration ash in cement industry. In fact, incineration bottom ash from municipal waste contains iron in 3-5%. Nonferrous metal and stainless steel in 1% is also included. The research and development on the physical recovery process was performed not only to remove the metals but also to recover high grade products. Metals were separated from incineration ash in Maruya Co. Ltd.. In fact, iron scrap recovered by magnetic separation can be selled. After that, mixed metal was separated from incineration ash using screen. In this research, mixed metal tried to divided copper, aluminum, brass and stainless steel using drum type magnetic separation, eddy current separation and high magnetic separation. As a result, recovered iron had an 80% for the grade. Aluminum was recovered by eddy current separation without copper and brass.

• 한국정밀공학회지
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• 제10권2호
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• pp.104-113
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• 1993

Characteristics of fiber-reinforced thermoplastic sheet depend on the quantity and shape of fibers. During a molding process of composites, the fiber-maxtrix separation and fober orientation are caused by the flow during the molding process. As a result, the product tends to be nonhomogeneous and anisotropic. Hence, it is very important to clarify the relations between separation-orientation and molding conditions. The correlation between the separation and the orientation have to be clarified for designing the fiber structure. In this paper, the degree of nonhomogeneity which is a measure of the separation is obtained using one-dimensional rectangular shaped part compression molding. And the orientation function is defined and measured by the image processing using soft X-rayed photograph and image scammer. Correlation between the degree of nonhomogeneity and the orientation function is discussed.

• 멤브레인
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• 제32권1호
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• pp.13-22
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• 2022

세계적인 에너지 수요의 증가는 통제할 수 없는 환경 오염을 야기하고 있다. 화석 연료에 대한 수요와 그로 인한 탄소 배출이 지구 온난화와 기후 변화로 이어진 것이다. 핵에너지는 청정 에너지를 생산하는 대체 자원이지만 핵연료 채굴은 유해한 화학물질과 관련이 있다. 반면에 막 분리 과정을 통해 바닷물에서 중요 광물을 채굴하는 것은 효율적이며 친환경적이다. 분리와 흡착을 통해 해수로부터 주요 광물을 채굴하는 것은 또 다른 효율적인 과정이다. 희토류 원소에서 악티늄족을 회수하는 것은 매우 어렵고 고비용의 과정이다. 압력 기반 막 분리 과정은 친환경적일 뿐만 아니라 경제적으로 실현가능한 과정이기도 하다. 본 리뷰에서 다루는 막 공정에는 폴리에테르 설폰, 폴리아미드, 폴리이미드, 폴리아미독신 및 하이브리드 막이 있다. 또한 흡착 공정의 경우, 주로 아미독심 종류의 흡착제가 논의될 것이다.