• Korean Chemical Engineering Research
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• 제53권5호
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• pp.584-589
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• 2015

잠수함 및 수중무인체계 등의 산소희박환경에서 연료전지를 통한 효과적인 전력생산을 위해서는 높은 수소저장밀도를 갖는 수소공급원이 필요하다. 디젤연료는 액체연료로서 저장 및 공급이 용이하며, 연료전지의 연료가 되는 수소의 단위질량 및 단위부피당 저장밀도가 높은 장점을 갖고 있다. 이러한 디젤연료의 장점을 기반으로 본 연구에서는 산소희박환경에서 수소생산을 위해 디젤연료의 개질반응을 이용하였으며, 산화제로 단위부피당 산소 저장밀도가 높고 액상으로 보관이 용이한 과산화수소 수용액을 기존의 산화제인 물과 산소의 대체산화제로 이용하는 방법을 제안하였다. 과산화수소 수용액의 디젤개질 산화제로써의 특성을 파악하기 위해 물, 공기 산화제와의 비교실험을 진행하였으며, 기존의 산화제와 디젤 개질반응 시 동일한 특성을 갖는 것을 실험적으로 확인하였다. 또한 상용디젤을 연료로 온도 및 과산화수소 수용액의 농도에 따른 개질성능을 평가하였으며, 49시간의 가속 열화실험을 통하여 디젤, 과산화수소 수용액을 이용한 수소생산의 가능성을 확인하였다.

• 한국수소및신에너지학회논문집
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• 제27권1호
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• pp.1-12
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• 2016

In this study, CFD model for a Heat Exchange Steam Reformer (HESR) used for a 10kW SOFC system is developed for the design optimization of the HESR. The model is used to explore the effect of design parameters on the performance of the HESR. In the HESR, heat is delivered from the hot gas channel to the fuel channel to supply the heat required for the fuel reforming. In the fuel channel where the fuel is reformed, thermo-fluid dynamics, heat transfer, and chemical reaction are considered to predict the performance of the reformer. The model is validated with experimental data within 2~3% error. The validated model is used for the parametric study of the HESR design. Channel length, channel diameter, and flow direction are selected as the design parameters. The effects of the HESR design parameters on the outlet temperature, outlet H2 mole fraction, and pressure drop across the reformer are presented using the model.

• 공업화학
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• 제27권5호
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• pp.537-542
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• 2016

본 연구에서는 불균일계 불소화 개질 공정을 이용하여 열분해잔사유(PFO)로부터 메조페이스 피치를 제조하였다. 이 공정은 다양한 온도의 직접 불소화 공정과 $390^{\circ}C$의 열처리 공정을 통하여 진행하였다. 제조된 피치는 연화점, 원소분석, 푸리에 변환 적외선 분광 분석, 고분해능 X-ray 회절 분석 그리고 편광 현미경 분석을 실시하였다. 제조된 피치의 탄소 함량은 직접 불소화 공정의 반응 온도 증가에 따라 함께 상승하였으며, 그 산소, 질소 그리고 황 성분은 완전하게 제거되었다. 불소화 온도가 증가함에 따라서, 메조페이스 소구체의 생성, 성장, 합체, 정렬이 관찰되었다. 탄소 육각망면의 층간간격이 감소하였고 결정자 크기가 증가하였다. 또한, 지방족 화합물의 축 중합으로 인한 방향족 화합물의 함량 증가가 관찰되었다. 이러한 결과는 반응 온도의 증가에 따라 증가된 불소 라디칼의 반응성에 기인한다. 불소화 반응은 열분해잔사유가 라디칼 반응에 의한 중합반응의 촉진으로, 방향족 화합물의 생성을 돕는 것으로 판단된다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.467-470
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• 2006

For a mobile application such as cellular phone, micro fuel cells should be extremely compact and thin. RHFC can be an alternative solution because RHFC gives higher power density than DMFC and does not need ahydrogen storage vessel In this paper, RHFC using methanol fuel is made as a novel planar design without a PROX. Both reformer and cell are made closely in a same plate to share the heater of reformer with the cell. The PBI membrane is used in the cell. The reason is that high temperature of reformer can cause a performance drop when perfluorosulfonic acid membrane such as Nafion is used such a high temperature operation also guarantees the higher CO tolerance to MEA catalyst. The cell is designed as an air-breathing type which the cathode of the cell is opened to the air. The commercial Cu/ZnO/Al2O3 steam reformer catalyst is packed in reformer channel. The active area of MEA is $11.9cm^2$ and the peak power density was $27.5mW/cm^2$.

• 에너지공학
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• 제2권2호
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• pp.200-207
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• 1993

본 논문은 5.9kW급 인산형 연료전지 발전시스템의 운전에 필요한 메탄올 연료개질기의 설계와 이의 운전 특성에 관한 것이다. 연료개질장치는 메탄올을 연소용 및 개질용연료로 사용하며, 개 질 반응 촉매는 CuO-ZnO계를 사용하고, 개질 반응기는 단일 환형 반응기 형태로 설계하였다. 개질 장치의 일산화탄소 생성 특성은 전체적으로 이론적인 평형값에는 도달하지 못하였으나, 반응온도가 증가할수록 농도가 증가하였으며, 개질 연료의 물/메탄올 몰비가 증가하면 감소하였다. 정격운전에서 촉매반응기의 축방향 온도분포는 이론적인 값과 잘 일치하였으며, 운전 개시후 50분 훈에 정상 운전이 가능하였다. 개질 시스템의 효율은 정격운전에서는 72.3%, 1/4 부하에서는 77%로 부하가 증가할수록 효율은 감소하였다. 개질기를 연료전지 본체와 연계운전시 개질기에 개질용 메탄올 및 연소용 메탄올의 공급유량이 각각 88.1 mol/h, 50.0mol/h 인 경우 정격전압인 37.6V의 전안에서 안정적인 5.5 kWh의 전력을 생산 할 수 있었다.

• Journal of Electrochemical Science and Technology
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• 제7권2호
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• pp.146-152
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• 2016

A combined system with PEMFC and reformer is introduced and optimized for the real use of this kind of system in the future. The hydrogen source to operate the PEMFC system is methanol, which needs two parts of methanol reforming reaction and preferential oxidation (PROX) for the hydrogen fuel process in the combined operation PEMFC system. With the optimized methanol steam reforming condition, we tested PROX reactions in various operation temperature from 170 to 270 ℃ to investigate CO concentration data in the reformed gases. Using these different CO concentration, PEMFC performances are achieved at the combined system. Pt/C and Ru promoted Pt/C were catalysts were used for the anode to compare the stability in CO contained gases. The alloy catalyst of PtRu/C shows higher performance and better resistance to CO than the Pt/C at even high CO amount of 200 ppm, indicating a promotion not only to the activity but also to the CO tolerance. Furthermore, in a system point of view, there is a fluctuation in the PEMFC operation due to the unstable fuel supply. Therefore, we also modified the methanol reforming by a scaled up reactor and pressurization to produce steady operation of PEMFC. The optimized system with the methanol reformer and PEMFC shows a stable performance for a long time, which is providing a valuable data for the PEMFC commercialization.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.180-183
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• 2007

CO in the reformed gas for proton exchange membrane fuel cell(PEMFC) has a strong tendency to adsorb on the surface of the catalyst and thus to block the sites that hydrogen needs for reactions. Even part per million levels of CO can cause serious poisoning. This CO poisoning can overcome to bleed trace amounts of air into the anode. In this study, we indicated the alteration of stack performance in various CO concentration and then bled a small amount of air. The performance of stack was reduced by increasing CO amount, and recovered by air bleeding. But the air-bleeding have an impact on performance of anode should be further explored.

• 한국연소학회지
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• 제22권1호
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• pp.23-31
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• 2017

Large-scale fuel tanks emit massive amount of hardly-combustible VOC mixtures which are light hydrocarbon species in dilution with nitrogen and carbon dioxide. We have developed a lab-scale burner to combust those VOC mixtures by use of a turbulent partially-premixed flame as a pilot flame. For a higher HC treatment ratio, the mixture gases were reformed by a rotating arc plasma device. The results showed that the nitrogen mole fraction and the injecting speed of the VOC mixture influence on the performance of the burner. It was also found that the size of the pilot flame and the power supplied to the plasma device determine the overall HC treatment ratio and the concentrations of CO and NOx in the exhaust gas.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.534-541
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• 2021

In this study, a novel microwave-matrix reformer was proposed to convert CH₄, which is a major component, to a high quality hydrogen energy. And to identify this performance, it was investigated for O₂/C ratio, steam feed amount and reformed gas recirculation which are affected for methane conversion and product gas yield. Through the parametric screening studies, optimal operating conditions were that O₂/C ratio, steam feed amount and recirculation rate were 1.1, 10 mL/min and 30 L/min. In this conditions, CH₄ conversion was 68.1%, H₂ selectivity 77.2 and H₂/CO ratio 2.62 which are possible applying SOFC stack for RPG (residential power generator).

• 한국자동차공학회논문집
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• 제15권6호
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• pp.137-143
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• 2007

An object of this study is to understand the application characteristics in accordance with changes of EGR rate, applying BD20 reformed by ultrasonic energy irradiation to common-rail diesel engine. BD containing about 10% oxygen has attracted attention due to soaring crude oil prices and environmental pollution. This oxygen decreases soot by promoting combustion, but it also increases NOx. To make up for this problem, an EGR system is applied so that NOx might be decreased. In that case, engine power is lowered and exhaust gas is raised. However, the reformed fuel by ultrasonic energy irradiation is changed physically and chemically, promotes combustion, and thus solves such a problem. As the results of the experimemt, we could identify the optimum EGR rate by investigating the engine performance and the characteristics of exhaust materials in accordance with the EGR rate after ultrasonic energy irradiation to BD20 and applying it to common-rail diesel engine. The optimum EGR rate that can satisfy both engine performance and characteristics of exhaust materials was in the range of 15%.