• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.81.2-81.2
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• 2010

고체 산화물 연료전지(SOFC) 시스템은 스택과 기계적 주변 장치인 MBOP(Mechanical Balance of Plant), 그리고 전기적 주변장치인 EBOP(Electrical Balance of Plant)로 구성되어있다. SOFC는 일반적으로 $700^{\circ}C$ 이상의 고온에서 작동되기 때문에 효율적인 열 이용 및 열 관리가 중요하다. SOFC 시스템의 MBOP에는 상온의 연료가스들을 고온으로 가열하여 스택에 유입 시기키 위한 열교환기 및 촉매연소기 등의 장치들이 필요하며, 효율적인 열관리를 위해서는 고온에서 작동하는 장치들을 한곳에 통합하여 구성하는 것이 필수적이다. 본 연구에서는 SOFC 시스템의 MBOP(Mechanical Balance of Pant) 중 고온부에 해당하는 촉매연소기, 열교환기 및 스택이 통합된 스택 모듈을 제작에 앞서 개념 검증을 위해 열교환기 및 촉매연소기로 이루어진 프로토타입(prototype)의 SOFC 모듈평가 장치를 제작하였다. 열교환기는 Plate형으로 총 6개로 구성되어 있으며, 연료극과 공기극 가스라인에 각각 3개씩 배치하여 스택에 유입되는 연료 및 공기가 촉매연소기에서 나오는 고온의 배가스와 열교환되어 가열되도록 구성하였다. 촉매연소기는 honeycomb 타입의 촉매를 사용하였고, 촉매연소기로 유입되는 연료극 배가스와 공기의 균일혼합과 hot spot을 방지하기 위한 장치를 삽입하여 제작하였다. 제작된 SOFC 모듈평가장치는 시운전을 통해 각 장치의 성능 확인 후 반응면적이 $20{\times}20cm^2$ 인 단전지를 적층하여 연계 운전을 수행하였다.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.989-994
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• 2001

Numerical simulations of high temperature catalytic combustion have been performed for the application to a gas turbine combustor. Dependences of inlet temperature and pressure on the distributions of temperature and species concentrations were investigated using plug flow model with detailed homogeneous and heterogeneous chemistries of methane-air mixtures. Honeycomb typecombustor deposited with Pt catalyst of 100mm in length and 26mm in diameter is used. The results show that rapid increase of temperature profile occurs earlier with the increase of inlet temperature and the decrease of inlet pressure. The condition which catalytic combustion is stabilized exists at certain range of inlet temperature and pressure. The state of catalytic combustion is also confirmed by the distributions of species concentration.

• Journal of the Korean Institute of Gas
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• v.5 no.1
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• pp.45-51
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• 2001

Catalytic combustion is the environmental-friendly technology, which has been applied to a variety of areas for industrial and domestic use in recent years. Accordingly, this study performed the development of the catalytic manufacturing technology for the high temperature and of the catalytic combustor in priority, which were aimed to be aimed to a commercialized condensing boiler. Palladium(Pd) of a noble meta] was used as a catalyst for the high temperature and supported on $alumina(Al_{2}O_{3})\;and\;zirconia(ZrO_2)$ in constant weight ratio. Activity of Pd catalysts is compared and analysed in the catalytic combustion of natural gas. The ratio of $Pd/Al_{2}O_{3}\;=\;4$ was found to be better than any other weight ratios in activity and durability. The performance examination of catalysts and of combustion through the plate-type combustor made it possible to be developed the cylindrical-type combustor which has increased combustion area. Catalytic combustion condensing boiler of 25,000 kcal/hr class was also developed, which had the optimum combustion condition at the no221e of 5.95mm and the orifice of 21mm. This condition was determined through the performance experiments of catalytic combustion condensing boiler to which the cylindrical-type catalytic combustor was applied.

• Clean Technology
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• v.25 no.4
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• pp.331-335
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• 2019

Interest in environmental pollution is increasing all over the world, and technology development to solve it is actively carried out. In areas where heat is used, especially, combustion is causing countless pollutants in the air environment. Combustion catalyst is a technology that reduces NOx and CO by lowering combustion temperature and enabling complete combustion. Traditional combustion catalysts are expensive and complex in the synthesis process using precious metal catalyst. In this study, hexaaluminate, a high-temperature combustion catalyst, was manufactured using urea, and the properties were investigated according to the synthesis time. The combustion performance and characteristics were evaluated using this catalyst. As the temperature increased, the changing methane conversion rate was shown in two patterns. The conversion rates for 1 hour, 9 hours, and 12 hours were similar, while the conversion rates for 3 hours and 6 hours showed similar patterns. Methane combustion performance increased rapidly as the synthesis time increased from 6 hours to 9 hours, whereas the temperature at T50 was approximately 745 ℃. The performance of the synthesized combustion catalyst for 9 hours was optimum as the NOx emission of this combustion catalyst was not present and the maximum emission of CO was 72 ppm.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.111.1-111.1
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• 2010

석탄가스화복합발전(IGCC: Integrated Gasification Combined Cycle)의 고온 고압 합성가스로부터 $CO_2$를 저비용으로 포집하기 위한 연소전 포집 기술 중 유동층 촉진수성가스전환(SEWGS) 공정이 제안되어 연구개발 중에 있다. 연소전 $CO_2$ 포집을 위한 SEWGS 공정은 동일한 2탑 순환 유동층 반응기에서 고온 고압의 합성가스($H_2$, CO)를 유동층 WGS 촉매를 사용하여 CO를 $CO_2$로 전환하는 동시에 전환반응으로 생성된 $CO_2$를 흡수제를 이용하여 포집하는 기술이다. 본 연구는 $CO_2$ 회수와 WGS 반응이 동시에 이루어지는 공정에 적용 가능한 건식 재생 흡수제 및 유동층 WGS 촉매 개발을 목표로 $CO_2$ 흡수제(P Series) 및 WGS 촉매(PC Series) 조성을 제안하고 분무건조기를 이용하여 6~8kg/batch로 성형 제조하였다. 제조된 $CO_2$ 흡수제 및 촉매의 특성 평가 결과 내마모도(Attrition resistance)를 포함한 물리적 특성이 유동층 공정의 요구조건을 만족하는 결과를 얻을 수 있었다. 또한, 모사 석탄 합성가스를 이용하여 20bar, $200^{\circ}C$ 흡수/$400^{\circ}C$ 재생 조건에서 열중량 분석기(TGA) 및 가압 유동층(Fluidized-bed) 반응기를 통한 흡수제의 $CO_2$ 흡수능 평가를 수행하였다. 그 결과 내마모도(AI) 3% 이하로 기계적 강도가 우수하며, $CO_2$ 흡수능 17.6 wt%(TGA) 및 11wt%(가압 유동층)를 나타냈다. 유동층 WGS 특성 평가 결과 내마모도가 7~35%로 우수하였고, CO 전환율은 $200^{\circ}C$에서 80% 이상으로, 유동층 SEWGS 공정에 적용 가능한 특성을 확인하였다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.9
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• pp.792-798
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• 2007

catalytic combustion is accomplished by the chemical reaction between fuel and oxidizer at the catalyst surface, different from conventional combustion. Therefore, it is important that the fuel and air stream are well mixed and supplied uniformly prior to the combustion region. If the flow is maldistributed, a hot spot may occur that can lead to subsequent catalyst and substrate damage. Therefore, in order to enhance the mixing and flow uniformity, in this study, the perforated plate is used. A numerical simulation is performed to investigate the variation of flow characteristics by changing various parameters. Under each condition, the uniformity of the flow stream at the entrance of the catalyst section is evaluated and compared. The results show that the uniformity can be effectively improved for most of the case by using the well-designed perforated plates.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.3
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• pp.511-521
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• 2000

Investigation was carried out lean burn de-NOx properties of Pt-$TiO_2$ bifunctional catalyst by propylene in order to get the high de-NOx activity and the wide temperature window under coexistence of $SO_2$ and $H_2O$. Only noncatalyst and carrier catalyst themselves had NOx conversion activity at high temperature over $400^{\circ}C$. NOx conversion activity of catalysts exchanged copper ion resulted in Cu-$TiO_2$>Cu-ZSM-5>Cu-$Al_2O_3$>CU-YZ>Cu-AZ. Catalysts impregnated with platinum based on titania gave the results of high NOx conversion activity at low temperature. $250^{\circ}C$. Bifunctional catalysts based on Pt-$TiO_2$ showed high NOx conversion activity both at a low zone of $300^{\circ}C$ and a high zone of $500^{\circ}C$. Pt-$TiO_2$/$Al_2O_3$ catalyst gave the highest NOx conversion activity at a low temperature zone. and Pt-$TiO_2$/$Mn_2O_3$(21) catalyst gave the highest NOx conversion activity at a high temperature zone. Under the coexistence of $SO_2$ and $H_2O$. NOx conversion activities of 0.55wt%Pt-$TiO_2$/5wt%Cu-ZSM-5 catalyst was high both at a low and high temperature zone, and increased depending on oxygen concentration. 0.55wt%Pt-$TiO_2$/5wt%Cu-ZSM-5 catalyst showed the best correlation between de-NOx activities and the propyl ere conversion rates to CO on the log function.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.6
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• pp.641-648
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• 2011

Off-gases emitted from the anode of a molten carbonate fuel cell (MCFC) at high temperatures for power generation are used as fuel in catalytic combustion. The heat generated in the catalytic combustor is utilized as the heat for the endothermic reaction required for steam reforming. Among the various operational conditions of the integrated reactor, we varied the inlet gas compositions of the catalytic combustor according to fuel utilization in the MCFC and the ratio of steam to carbon in the reformer. Subsequently, the thermal behaviors and reaction characteristics of the integrated reactor were investigated experimentally. The fundamental data from this experimental study will be useful for the design and fabrication of a more practical integrated reactor in the future.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.4
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• pp.405-412
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• 2012

In the MCFC power generation system, the combustor supplies a high temperature mixture of gases to the cathode and heat to the reformer by using the off-gas from the anode; the off-gas includes high concentrations of $H_2O$ and $CO_2$. Since a combustor needs to be operated in a very lean condition and avoid local heating, a catalytic combustor is usually adopted. Catalytic combustion is also generally accepted as one of the environmentally preferred alternatives for generation of heat and power from fossil fuels because of its complete combustion and low emissions of pollutants such as CO, UHC, and $NO_x$. In this study, experiments were conducted on catalytic combustion behavior in the presence of Pd-based catalysts for the BOP (Balance Of Plant) of 5 kW MCFC (Molten Carbonate Fuel Cell) power generation systems. Extensive investigations were carried out on the catalyst performance with the gaseous $CH_4$ fuel by changing such various parameters as $H_2$ addition, inlet temperature, excess air ratio, space velocity, catalyst type, and start-up schedule of the pilot system adopted in the BOP.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.923-927
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• 2017

Metal exposed to high temperature/high pressure/oxidizer-rich environment may cause rapid oxidation(ignition and combustion). Therefore, this study was performed for the selection of metal appropriate for high temperature/high pressure/oxidizer-rich environment. In order to make the high temperature, high pressure and oxidizer-rich environment, the test facility utilizing the catalytic reaction of hydrogen peroxide was constructed and the metal oxidation and ignition of the STS series metals were evaluated. The result showed that the change of the selected material (discoloration) and the surface roughness were observed, but the change in the weight and thickness of the specimen was not significant.