• 한국태양에너지학회 논문집
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• 제33권3호
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• pp.91-98
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• 2013

In this study, we have carried out development and performance evaluation of optimized MEMS(Multi-Effect-Multi-Stage) fresh water generator with $7m^2/day$ for solar thermal desalination system. The developed MEMS was composed of high temperature part and low temperature part. This arrangement has the advantage of increasing the availability of solar thermal energy. The MEMS consists of 2 steam generators, 5 evaporators, and 1 condenser. Tubes of heat exchanger used for steam generators, evaporators and condenser were manufactured by corrugated tubes. The performance of the MEMS was tested through in-door experiments, using an electric heater as heat source. The experimental conditions for each parameters were $20^{\circ}C$ for sea water inlet temperature to condenser, $8.16m^2$ /hour sea water inlet volume flow rate, $70^{\circ}C$ for hot water inlet temperature to generator of high temperature part, 3.6 4.8, 6.0 $m^2/hour$ for hot water inlet volume flow rate. As a result, The developed MEMS was required about 85 kW heating source to produce $7m^2/day$ of fresh water. It was analyzed that the performance ratio of MEMS was about 2.6.

• 대한기계학회논문집B
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• 제40권7호
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• pp.477-484
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• 2016

다중효용 태양열 담수기에서 다중효용부 각 효용단의 해수 공급유량은 효용수 증가에 따른 열에너지 감소를 고려하여 점차 줄어드는데, 선행연구에서는 효용단 별 서로 다른 공급유량 감소율을 제시하였다. 이론적으로 열에너지 감소율이 일정하기 때문에 효용단 별 서로 다른 유량감소율은 적절하지 않다. 본 논문에서는 수치해석을 통해 다중효용부의 공급유량 감소율에 따른 담수생산량 특성을 분석하였다. 해석결과 공급에너지가 같은 조건(12MJ)에서 동일한 감소율(11%)일 때와 그렇지 않을 때의 생산량 차이는 0.56%로 거의 비슷하였다. 또한 수치해석을 통해 고온의 배기가스로부터 얻은 공급 에너지량에 따라 다중효용부 해수공급유량의 최적값을 도출하였다. 최적 유량은 에너지의 공급 형태에 따라 선형적으로 증가하거나 증가 후 평형상태에 도달하는 현상이 발생하였다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2019년도 춘계학술논문요약집
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• pp.69-69
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• 2019

The distillation of liquid cathode is necessary to separate cadmium from the actinide elements in the pyroprocessing since the actinide deposits are dissolved or precipitated in a liquid cathode. It is very important to avoid a splattering of cadmium during evaporation due to the high vapor pressure. Several methods have been proposed to lower the splattering of cadmium during distillation. One of the important methods is an installation of crucible cover on the distillation crucible. A multi-layer porous round cover was proposed to avoid a cadmium splattering in our previous study. In this study, the effect of crucible cover on the cadmium distillation was examined to develop a splatter shield. Various surrogates were used for the actinides in the cadmium. The surrogates such as bismuth, zirconia, and tungsten don't evaporate at the operational temperature of the Cd distiller due to their low vapor pressures. The distillation experiments were carried out in a crucible equipped with cover and in a crucible without cover. About 40 grams of Cd was distilled at a reduced pressure for two hours at various temperatures. The mixture of the cadmium and the surrogate was heated at $470{\sim}620^{\circ}C$. Most of the bismuth remained in the crucible equipped with cover after distillation under $580^{\circ}C$ for two hours, whereas small amount of bismuth decreased in the crucible without cover above $580^{\circ}C$. The liquid bismuth escaped with liquid cadmium drop from the crucible without cover. It seems that the crucible cover played a role to prevent the splash of the liquid cadmium drop. The effect of the cover was not clear for the tungsten or zirconia surrogate since the surrogates remained as a solid powder at the experimental temperature. From the results of this work, it can be concluded that the crucible cover can be used to minimize the deposit loss by prevention of escape of liquid drop from the crucible during distillation of liquid cathode.