• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.857-859
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• 1992

The molten carbonate fuel cell is a new method for generating power which uses coal gasification gas and reformed liquid natural gas for fuel at very high efficiency and with minimal pollution. The purpose of this research is to investigate principle, properties and research status of internal reforming molten carbonate fuel cell.

• 한국막학회:학술대회논문집
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• 한국막학회 1996년도 춘계 총회 및 학술발표회
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• pp.30-32
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• 1996

Although the transport of small molecules through polymer membranes has been extensively studied for a long time, understanding of the transport mechanism is still far from satisfactory. This in turn makes difflcult the search for new membrane materials with the desired transport characteristics. Therefore it is of the utmost interest to study the correlations between a polymer's structure and morphology and its transport properties. Generally, polyurethanes serve as excellent polymer materials for such studies since their physical and chemical properties can be widely and systematically modified by varying the length, composition and chemical structure of the hard and soft segments. In this paper liquid crystalline polyurethanes are presented as new membrane materials for liquld separation and their transport properties with respect to molecular and supermolecular-structure are discussed.

• 한국가스학회:학술대회논문집
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• 한국가스학회 2007년도 춘계학술발표회 논문집
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• pp.33-36
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• 2007

합성가스는 C1화학을 시작하는 반응원료 물질로 최근 DME(dimethyl-ether), 메탄올, GTL(gas to liquid), CTL(coal to liquid), 암모니아 생성 공정 등 많은 화학공정에 사용되고 있다. 합성가스를 생산하는 방법은 천연가스 개질반응과 석탄의 가스화반응, 그리고 원유의 정제 등을 통해 얻을 수 있다. 삼중개질반응은 천연가스와 산소, 수증기, 이산화탄소를 원료로 $1000^{\circ}C$ 이상의 고온에서 반응시켜 합성가스를 생산하며, 균일반응계와 불균일반응계로 이루어져 있다. 균일반응계에서는 천연가스와 산소가 주로 반응하며, 원료로 투입된 대부분의 산소는 균일반응계에서 소모되어 일산화탄소와 이산화탄소를 생성한다. 삼중개질반응의 균일반응계에서는 산소와 천연가스와의 반응으로 많은 발열이 발생하여 전체 반응계의 온도를 유지할 수 있도록 해준다. 본 연구에서는 산소로 인한 삼중개질반응의 온도 조절과 균일반응계의 온도 분포를 위치에 따라 관찰해 보았으며, 실험과 모사를 통해 비교해 보았다.

• 대한기계학회논문집
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• 제14권5호
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• pp.1330-1336
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• 1990

The factors to act on atomization of liquid fuel are viscosity, geometric shape of nozzle, atomizing pressure, etc. Most of high viscous liquid fuels show decrease in viscosity by raising the preheat temperature, but the viscosity of liquid fuel like CWM does not readily change with fuel temperature. As an experimental study to investigate the atomizing characteristics of CWM, CWM fuel is atomizing with a twin-fluid atomizer, and the effects of the geometric shape of spray nozzle on atomization are investigated by measuring the Sauter`s Mean Diameter (SMD) of CWM. The summarized results obtained in this study are as follows ; (1) As the ratio of the mass flows of atomizing air to that of fuel (W$_{a}$ /W$_{1}$) increases, 능 decreases when fuel temperature is constant. (2) At the ratio (t/d) 4 of thickness (t) of spray nozzle hole to the diameter (d) of the hole, there is the best atomization. And SMD decreases when t/d is between 1 to 4 and increases when t/d > 4.

• 한국수소및신에너지학회논문집
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• 제22권6호
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• pp.905-912
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• 2011

In this study, the novel concept catalytic reactor was designed for water-gas shift reaction (WGS) under high pressure. The novel concept catalytic reactor was composed of an autoclave, the catalyst, and liquid water. Cu-ZnO/$Al_2O_3$ as the low temperature shift catalyst was used for WGS reaction. WGS in the novel concept catalytic reactor was carried out at the ranges of 150~$250^{\circ}C$ and 30~50 atm. The liquid water was filled at the bottom of the autoclave catalytic reactor and the catalyst of pellet type was located at the gas-liquid water interface. It was concluded that WGS reaction occurred over the surface of catalysts partially wetted with liquid water. The conversion of CO for WGS was also controlled with changing content of Cu and ZnO used as the catalytic active components. Meanwhile, the catalyst of honey comb type coated with Cu-ZnO/$Al_2O_3$ was used in order to increase the contact area between wet-surface of catalyst and the reactants of gas phase. It was confirmed from these experiments that $H_2$/CO ratio of the simulated coal gas increased from 0.5 to 0.8 by WGS at gas-liquid water interface over the wet surface of honey comb type catalyst at $250^{\circ}C$ and 50 atm.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1996년도 춘계 학술대회논문집
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• pp.58-67
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• 1996

This paper describes some computational results of various energy and environmental systems using Patankar's SIMPLE method. The specific topics handled in this study are jet bubbling reactor for flue gas desulfurization, cyclone-type afterburner for incineration, 200m tall stack for 500 MW electric power generation, double skin and heat storage systems of building energy saving for the utilization of solar heating, finally turbulent combustion systems with liquid droplet or pulverized coal particle. A control-volume based finite-difference method with the power-law scheme is employed for discretization. The pressure-velocity coupling is resolved by the use of the revised version of SIMPLE, that is, SIMPLEC. Reynolds stresses are closed using the standard $k-{\varepsilon}$ and RNG $k-{\varepsilon}$ models. Two-phase turbulent combustion of liquid drop or pulverized coal particle is modeled using locally-homogeneous, gas-phase, eddy breakup model. However simple approximate models are incorporated for the modeling of the second phase slip and retardation of ignition without consideration of any detailed particle behavior. Some important results are presented and discussed in a brief note. Especially, in order to make uniform exit flow for the jet bubbling reactor, a well-designed structure of distributor is needed. Further, the aspect ratio in the double skin system appears to be one of important factors to give rise to the visible change of the induced air flow rate. The computational tool employed in this study, in general, appears as a viable method for the design of various engineering system of interest.

• 한국토양비료학회지
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• 제41권5호
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• pp.324-329
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• 2008

A coal mine drainage sludge(designated as CMDS) is mainly generated during physicochemical treatment or electrical purification of the drainage abandoned mine that include dissolved heavy metal. To understand the possibility of an application of the dehydrated CMDS as the landfill cover medium of hygienic a reclaimed ground, an laboratory experiment was performed to investigate the physicochemical and geoengineering characteristics of the dehydrated CMDS. To improve the geoengineering characteristics of the dehydrated CMDS, the liquid limit, plasticity limit test, compaction method test, strength test, and hydraulic conductivity test ware performed with the lithification material mixed sludge. When the mixed ratio of the sludge and the lithification material was more than 1:06, the compaction method was A method, the moisture content less than 33.5%, the strength of mixed sludge was $8.2kg\;cm^{-2}$, the hydraulic conductivity was $2.7\times10^{-6}cm\;sec^{-1}$, the sludge was up to the landfill standard of US Environmental Protection Agency (US EPA).

• Metals and materials international
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• 제24권6호
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• pp.1262-1274
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• 2018

The inhibition of gravity segregation has been a long-standing challenge in fabrication and applications of homogeneous immiscible alloys. Therefore, the effect of rare-earth La on the gravity segregation of Al-Bi immiscible alloys was investigated to understand the homogenization mechanism. The results showed that the addition of La can completely suppress the gravity segregation. This is attributed to the nucleation of Bi-rich liquid phase on the in-situ produced $LaBi_2$ phase and the change of the shape of $LaBi_2@Bi$ droplets. In addition, a novel strategy is developed to prepare the homogeneous immiscible alloys through the addition of rare-earth elements. This strategy not only is applicable to other immiscible alloys, but also is conducive to finding more elements to suppress the gravity segregation. This study provided a useful reference for the fabrication of the homogeneous immiscible alloys.

• Asian Journal of Atmospheric Environment
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• 제10권2호
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• pp.90-98
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• 2016

Total suspended particulates (TSP) in the atmosphere were collected for 2 weeks during winter in Muroran, Hokkaido, Japan, a typical iron-manufacturing city. The concentrations of polycyclic aromatic hydrocarbons (PAHs) and nitropolycyclic aromatic hydrocarbons (NPAHs) in TSP were determined by high-performance liquid chromatography (HPLC) using fluorescence and chemiluminescence detectors, respectively. No relationship was observed between the atmospheric PAH and NPAH concentration, or the atmospheric PAH and TSP concentration. However, there was a tendency that the atmospheric PAH concentration was higher when the wind blew from the coke-oven plant. Furthermore, the concentration ratios of 1-nitropyrene to pyrene, which is a suitable indicator of the contribution made by automobiles and coal combustion systems to urban air particulates, were smaller in Muroran and the values were close to those observed in particulates from coal combustion systems. Therefore, these results show that the PAH and NPAH compositions for Muroran are characteristic of an iron-manufacturing city.

• 플랜트 저널
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• 제17권2호
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• pp.32-41
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• 2021

최근 미세먼지 등 대기환경 문제가 국가적 이슈로 급부상 하고있는 추세이며 특히 석탄화력발전소에 대한 강도높은 환경규제치가 적용되고 있는 실정이다. 본 연구는 석탄화력발전소 주요 대기오염 배출물질인 황산화물과 먼지 제거를 위한 탈황설비 성능개선 사례에 대해 소개하고 있으며 현재 운영중인 1,000 MW 발전소의 성능개선을 위한 네가지 Case Study를 수행하고 공사를 하였다. 탈황설비 흡수탑 개조를 통해 액기비를 증대시켰으며 산화공기 유량을 증대시켜 기액 반응을 촉진하였다. 또한 가스가스히터 누설률을 개선하여 최종 탈황설비 효율을 향상시켰다. 기존 설비와 조화를 고려한 성능개선 공사를 통해 2023년부터 적용될 규제치(황산화물 25ppm, 먼지 5mg/Sm³)를 만족할 것으로 예상되며 타 화력발전소에 검토 및 적용하는데 참고될 수 있다고 기대된다.