• 한국기계가공학회지
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• 제17권4호
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• pp.23-31
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• 2018

Stress of a steam separator, equipment of the high-pressure (HP) evaporator for a HRSG, was analyzed and evaluated according to ASME Boiler & Pressure Vessel Code Section VIII Division 2. First, from the analysis results of the piping system model of the HP evaporator, reaction forces of the riser tubes connected to the steam separator, i.e., nozzle loads, were derived. Next, a finite element model of the steam separator was constructed and analyzed for the design pressure and the nozzle loads. The results show that the maximum stress occurred at the bore of the riser nozzle. The primary membrane stresses at the shell and nozzle were found to be less than the allowable stress. Next, the steam separator was analyzed for the steady-state operating conditions of operating pressure, operating temperature, and nozzle loads. The maximum stress occurred at the bore of the riser nozzle. The primary plus secondary membrane plus bending stress at the shell and nozzle was found to be less than the allowable stress.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 춘계학술발표회
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• pp.103-108
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• 2006

새롭게 적용되는 IMO 규정에 적합한 선박의 15ppm Bilge Separator를 개발하기 위하여 Bilge 폐수에 함유된 Emulsion 의 처리가 매우 중요하다. 에멀젼의 경우 그 안정성으로 인해 육상에서도 처리하기가 매우 까다로운데 본 연구에서는 화학적인 방법을 이용하여 Emulsion의 안정성을 파괴하여 처리하고자 하였다 파괴된 기름 입자는 서로 응집하여 부상처리 되는데, 선박은 특성상 장치의 설치장소가 협소하기 때문에 Bilge 폐수의 처리에 시간이 충분치 않다. 이러한 문제의 해결과 화학적 처리에 가장 기본이 되는 응집제의 선정과 기본적인 환경요인들을 결정하여 실험을 진행하였다. 실험결과 국내 제품 중의 응집제를 선정하였고 가장 응집 효과가 좋은 pH 영역과 응집제의 투여량을 결정하였으며 기초 실험을 통해 최적효율을 나타내는 부상방법을 결정하여 이를 바탕으로 Pilot Plant를 제작하여 에멀젼 함유 Bilge 폐수를 처리한 결과 IMO에서 정한 기준을 만족하는 결과를 얻을 수 있었다.

• Journal of Biosystems Engineering
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• 제9권1호
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• pp.22-33
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• 1984

Husk separator is an indispensable equipment in rice milling plants. However, any basic research on the designing and operating criteria of the husk separator have rarely been conducted in Korea. According to the survey results reported recently, grain loss occurs in the process of rice husk separation at custom rice milling plants in Korea and the performance of husk separator has also not been identified. With this regard this study was conducted with a typical commercial husk separator to investigate the effect of the operational factors such as feed rate, blower speed and opening ratio on the velocity distribution in the air duct and the performance of the separator. The results are summerized as follows: 1. The average wind velocity in the primary air duct increased linearly with the blower rpm and the size of air inlet port in both cases of double type and single type operations. 2. The coefficient of variation in the horizontal wind velocities in the primary air duct was the minimum when the opening ratio was 0.22 ($0.052m^2$ of air inlet port) in both cases of single type and double type operations regardless of the blower speeds used in this test. The average wind velocity at the upper part of air duct was greater by 2-5 m/s than the velocity at the bottom part in double type operation. In case of single type operation, however, the average velocity in the middle part was greater than the upper or bottom part when the opening ratio was greater than 0.74. 3. The relationship between the overall effectiveness of separation(Ed for double type and Es for single type) and the average wind velocity (Va) in the primary air duct was expressed in the following quadratic functions. $$Ed=-190.84+106.18Va-10.052Va^2$$ ($r^2$ = 0.97782) $$Es=-223.76+106.23Va-9.1935Va^2$$ ($r^2$ = 0.97029) The average wind velocity required to obtain the overall effectiveness of separation more than 80% ranged from 4.04 m/sec to 5.84 m/sec in case of double type operation, and from 4.70 m/sec to 6.20 m/sec in case of single type. 4. An optimum wind velocity can be obtained with an increase in the blower speed or the size of air inlet port as presented in Figure 8. There was a tendency that the faster the blower speed, the narrower the control range of the air inlet port. 5. The feed rates (1850kg/hr and 2100kg/hr) adopted in this experiment did not bring about a significant difference in both the overall effectiveness of separation and the power consumption. 6. The energy consumption increased cubically with the blower speed but linearly with the size of the air inlet port. On the basis of the results described in items 1, 3, and 6, it would be more economic to adjust the size of the air inlet port larger with a relatively low blower speed than to adjust the size smaller with a relatively high speed.

• 상하수도학회지
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• 제24권4호
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• pp.443-451
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• 2010

This study was conducted to confirm the CSOs characteristics, and to estimate treatment efficiency of CSO treatment process. Flowrate was average $53,500m^3$/d, maximum $58,100m^3$/d during dry season, but after rain-fall, the flowrate was increased more than twice that of the dry season. And, water pollution concentrations, such as $COD_{Cr}$, SS, $BOD_5$, TN and TP of after rain-fall, were also increased. Thus, for more efficient treatment of pollutants during rainy season, The vortex separator and continuous fiber filter devices were used. From the results on particle range, removal efficiency of particle was 99.7% at the particle size range of $40{\sim}100{\mu}m$ but decreased as 55-80% at the below $40{\mu}m$. The removal efficiencies of $COD_{Cr}$, SS, TN and TP were approx. 70, 60, 70 and 50, respectively during the dry season and approx. 50, 50, 8 and 18% during the rainy season. Also, when compared with the primary sediment basin, $COD_{Cr}$, SS, TN and TP removal efficiencies were high. especially, at the case of TN and TP, TN was more removed than TP because of higher conversion factor value. But we needed more study for the injection of a coagulants to get more stable treatment efficiency for soluble pollutants. Consequently, This process can be used for CSOs treatment as well as replace the primary sedimentation basin during the dry season.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.219.1-219
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• 1999

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 추계학술대회 논문집
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• pp.175-179
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• 2005

새롭게 적용되는 IMO 규정에 적합한 Bilge Separator를 개발하기 위하여 Bilge 폐수에 함유된 Emulsion의 처리가 매우 중요하다. 에멀젼의 경우 그 안정성으로 인해 육상에서도 처리하기가 매우 까다로운데 본 연구에서는 화학적인 방법을 이용하여 Emulsion의 안정성을 파괴하여 처리하고자 하였다. 파괴된 기름 입자는 서로 응집하여 부상처리 되게 되는데, 선박은 특성상 장치의 설치장소가 협소하기 때문에 Bilge 폐수의 처리에 시간이 충분치 않다. 이러한 문제의 해결과 화학적 처리에 가장 기본이 되는 응집제의 선정과 기본적인 환경요인들을 결정하여 실험을 진행하였다. 실험결과 국내 제품 중의 응집제를 선정하였고 가장 응집효과가 좋은 pH 영역과 응집제의 투여량을 결정하여 이를 바탕으로 에멀젼 함유 Bilge 폐수를 처리한 결과 IMO에서 정한 기준을 만족하는 결과를 얻을 수 있었다.

• 한국전기전자재료학회논문지
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• 제28권7호
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• pp.467-472
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• 2015

Thermal batteries are primary power sources for military applications requiring high reliability, robustness and long storage life. Conventional electrodes for thermal batteries are prepared by compacting powder mixtures into pellets. Separator is composed of halide mixture, such as LiCl-KCl eutectic salt, blended with MgO to immobilize the molten salt. In order to increase the power density and energy density, the resistance of electrolyte should be reduced because the resistance of electrolyte is predominant in thermal batteries. In this study, wetting behaviors and impregnation weight of molten salts as well as the micro structures of ceramic felt were investigated to be applicable to thin electrolyte. Discharge performances of single cell with the ceramic separator impregnated by molten salt were evaluated also. Zirconia felt with high porosity and large pore outperformed alumina felt in wetting characteristics and molten salt impregnation as well as discharge performances. Based on the results of this study, ceramic felt separator impregnated with molten salt have revealed as an alternative of conventional thick MgO based separator with no conspicuous sign of thermal runaway by short circuit.

• 대한기계학회논문집B
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• 제41권9호
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• pp.571-577
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• 2017

본 연구는 수치해석 기법을 활용하여 오일샌드 플랜트에 사용되는 다상유동분리기의 다양한 유입구 형상에 따른 효율 분석에 관한 연구이다. 본 연구에 사용된 유수분리기(FWKO, Free-water knockout)는 유량 $15,89m^3/d$(100 bbl/d), SOR(Steam-to-Oil Ratio) 3.5의 값을 가지며 Stokes 이론을 기반으로 설계되었다. 모듈화를 위하여 두 개의 유수분리기를 병렬 연결하였고 이에 따른 유입구 형상 최적화를 수행하였다. 유입구를 통해 유입되는 비투멘 에멀젼은 $150^{\circ}C$, 50 bar이며, API는 17의 값을 갖는다. 유수분리공정의 평균체류시간은 물과 오일이 95% 분리되는 시간으로 정의하였다. 다상유동의 밀도차에 의한 중력분리과정을 모사하기 위하여 유한체적법(VOF, Volume Of Fluid)과 상차분모델(DPM, Discrete Phase Model)을 조합하여 활용하였으며 준과도(Pseudo-transient) 해석기법을 활용하였다.

• Journal of Electrochemical Science and Technology
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• 제1권1호
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• pp.39-44
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• 2010

1.5 V and 3.0 V-class film-type primary batteries were designed for radio frequency identification (RFID) tag. Efficient fabrication processes such as screen-printings of conducting layer ($25{\mu}m$), active material layer ($40{\mu}m$ for anode and $80{\mu}m$ for cathode), and electrolyte/separator/electrolyte layer ($100{\mu}m$), were adopted to give better performances of the 1.5 V-class film-type Leclanch$\acute{e}$ primary battery for battery-assisted passive (BAP) RFID tag. Lithium (Li) metal is used as an anode material in a 3.0 V-class film-type $MnO_2||$Li primary battery to increase the operating voltage and discharge capacity for application to active sensor tags of a radio frequency identification system. The fabricated 3.0 V-class film-type Li primary battery passes several safety tests and achieves a discharge capacity of more than 9 mAh $cm^{-2}$.

• Korean Chemical Engineering Research
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• 제54권6호
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• pp.800-805
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• 2016

나노기술의 급격한 발전은 다양한 산업응용분야에 기여를 하고 있다. 그러나 나노제품의 증가와 함께, 비의도적인 환경노출이 발생되고 있다. 나노제품에 의한 잠재적인 환경영향은 전과정평가(LCA)를 통해 해석할 수 있다. LCA는 제품의 생산과 폐기에 이르는 전체 공정상의 자원소모 및 배출에 관한 체계적인 해석을 할 수 있다. 본 연구에서는, 나노-$TiO_2$를 이용한 초친수성 유수분리필터를 제조하는 공정에 관하여 LCA를 수행하였다. 이를 위해 무료로 공개된 $TOTAL^{TM}$을 사용하였으며, 6대 환경영향인자인 자원소모, 기후변화, 오존층영향, 산성화, 부영양화, 광화학산화물생성 등의 지표를 해석하였다. 또한 나노-$TiO_2$를 사용하는 것이 유수분리필터 제조공정에서 벌크-$TiO_2$를 사용하는 것보다 긍정적으로 환경영향인자에 기여하는 것으로 파악되었다.