• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.11a
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• pp.67-70
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• 1999

최근에 들어서 태양에너지의 화학적 에너지로의 변환에 대한 연구는 에너지 부족에 대한 대안으로서 각광을 받고 있는 분야이다. 이런 관심을 바탕으로 한 다양한 연구는 연속식 또는 회분식 반응기를 이용한 불균일계 촉매를 이용함으로써 진행되고 있고, 특히 기-액, 기-고 그리고 기-액-고상 반응기를 응용하는 광촉매 반응에 관심이 증폭되고 있다. 그리고 광촉매 반응이 실제 산업계에서 활용되기 전에 먼저 불균일계 광촉매 반응기의 설계기준에 대한 연구가 선행되어야 하며 실제 산업적인 응용측면에서도 광촉매 반응의 충분한 이용가능성에 관심이 이루어져야 한다.(중략)

• Solar Energy
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• v.14 no.2
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• pp.91-101
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• 1994

Heat release characteristics of a CaO packed bed reactor which is used for a chemical heat storage device has been studied. We employed Cu-plate fins to release the heat of reaction of the CaO packed bed inside the reactor fast and effectively. Two-dimensional analysis of unsteady state heat flow inside the bed was performed as a function of time and under various conditions of the Cu-plates. It is noted that the time required to release the heat of reaction with Cu fins is reduced more than twice fast compared to that without Cu fins. That was largely dependent upon the number of Cu-plate, as well.

• Proceedings of the KSEEG Conference
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• 2007.04a
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• pp.333-335
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• 2007

• Proceedings of the KSEEG Conference
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• 2007.04a
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• pp.336-338
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• 2007

• Solar Energy
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• v.15 no.3
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• pp.29-38
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• 1995

The heat-storage characteristics accompanied by exothermic reaction at the regeneration of $Ca(OH)_2$ in tile heat-storage mode of a chemical heat pump system using a $Ca(OH)_2/CaO$ reversible thermochemical reaction was examined in a lab-scale unit. In this heat-storage mode, the particle bed of CaO could be regenerated by heating the $Ca(OH)_2$ packed bed to the higher temperature at which the equilibrium pressure in the reactor is greater than the water vapor pressure in the condenser. The results are i) the dehydration, thermal decomposition, rate of $Ca(OH)_2$ was higher at the lower part of particle bed than at the upper part, ii) in the reactor, the dehydration was proceeded along radial and axial direction, from inner part to the outer part, which explains heat transfers from the center to wall and from the tenter to lower or upper part of reactor.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.278-285
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• 2005

In the present work, a reaction of sulfur removal and simulation of desulfurization based on the grain model and two-phase theory were studied using natural manganese ore (NMO) as a sorbent in a continuous fluidized bed reactor. The effect of desulfurization was investigated through the grain model considered the change of pore structure as a function of desulfurization time, particle size of NMO, and diffusion velocity of $SO_2$ in the pores. Among these parameters, the diffusion of $SO_2$ in the pores of NMO was the most important factor. Moreover, the reaction of sulfur removal and desulfurization in a continuous fluidized bed reactor using NMO as a sorbent could be well predict through the grain model and two-phase theory, respectively.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.259-261
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• 2009

Solar simulator를 이용한 프로판의 수증기 개질은 집광된 태양에너지를 이용하기 위한 목적으로 수행되었다. 본 연구에서는 이와 같은 태양열에너지의 화학적 축열을 실시하기 위해 Solar Simulator를 이용한 메탄의 수증기 개질을 연구하였다. 태양열 모사 램프로 1.24kW급 Xenon-arc lamp를 사용하였다. 반응기는 앞면의 Quartz window와 Absorber로 구성되어 있다. 램프의 빛은 Quartz window를 통하여 촉매층에 직접적으로 방사된다. 프로판의 수증기개질 반응은 고온에서 일어나기 때문에 열에 강한 SiC로 만들어진 Ceramic foam을 Absorber로 사용하였다. 촉매는 Absorber에 Wash-coat하여 사용하였으며, 담지된 촉매는 Ni을 활성성분으로 하는 ICI 46-6와 귀금속 촉매인 Ru/$Al_2O_3$를 사용하였다. 반응기는 SUS 재질로 제작되었으며, 반응기 외부는 Insulation을 하여 열손실을 감소시켰다. Propane과 Steam의 비율은 S/C ratio를 3으로 하여 실험하였다. 실험은 온도와 촉매에 따른 Solar Steam reforming의 반응특성을 분석하였다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.05a
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• pp.207-212
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• 1999

화학반응이 일어나는 고정층 반응기의 성능을 모사하고 해석하기 위해서는 반응베드의 열 및 물질전달 특성을 정확히 아는 것이 중요하다. 본 연구에서는 화학열펌프에 사용되는 금속염-팽창흑연 다공성 반응매체의 유효열전도도와 기체투과도를 측정하였다. 유효열전도도는 전이 일차원 열류기법을 이용하여 측정하였고, 기체투과도는 Darcy's law를 이용하여 측정하였다. 팽창흑연이 함유된 반응베드의 유효열전도도와 기체투과도는 흑연을 기준으로 한 겉보기밀도에 따라 각각 14.1-36.5 W/mK, 8.0x$10^{-15}$-$10^{-12}$ $m^2$의 범위에 있었다.

• Analytical Science and Technology
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• v.17 no.4
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• pp.355-362
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• 2004

Fission products and Inter reaction layer of $U_3Si-Al$ dispersion fuel, irradiated in HANARO research reactor with 121 kW/m of maximum liner power and 63 at% of average burn-up, was characterization by EPMA (Electron Probe Micro Analyzer). The fuel punching system developed by Irradiated Materials Examination Facility (IMEF) has used to make these samples for the EPMA. With this system a very small and thin specimen which is 1.57 mm in diameter and 2 mm in thickness respectively has been fabricated to protect the EPMA operator from high radioactive fuel and to mini-mize the equivalent dose rate less than 150 mSv/h. EPMA was performed to observe layers of sectional, Inter-reaction and oxide with specimens of cutting and polished. Stoichiometry in the Inter-reaction layer with $16{\mu}m$ of thickness was $U_{2.84}$ Si $Al_{14}$ with calibration of $UO_2$ and $U_{3.24}$ Si $Al_{14.1}$ with calibration of standard specimen. metallic precipitates in this layer were not observed using fission products examination.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.4
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• pp.212-222
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• 1997

Geochemistry of metasedimentary groundwaters and spar waters has been studied in comparison with that of granitic groundwaters in Korea. Metasedimentary groundwaters show $Ca^{2+]$-${HCO_3}^-$ type at depth and low sodium concentrations compared with granitic groundwaters, which is due to the lack of plagioclase in their aquifer mineralogy and, therefore, the predominant reaction of calcite dissolution. According to factor analysis, metasedimentary groundwaters at 100~300 m depth are represented by 1) the dissolution of calcite and Mg-carbonates, 2) transformation of kaolinite to illite, and 3) the presence of sodium as not the product of plagioclase dissolution but a artificial pollutant. Discriminant function between the granitic and metasedimentary groundwaters shows a good discriminating ability with 81.8%, and groundwaters of volcanic aquifer, which has abundant plagioclase, are included in the granitic group by this function. Spa water samples show the result of active water-rock interaction due to high temperature.