• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.228-232
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• 2010

In this paper, various operating parameters of stream reforming process from methane in preconverter for MCFC is studied by numerical method. Commercial code is used to simulated the porous catalyst with user subroutine to model three dominant chemical reactions which are Stream Reforming(SR), Water-Gas Shift(WGS), and Direct Stram Reforming(DSR). The hydrogen production is tested with different wall temperature, Gas Hourly Space Velocity(GHSV), and different reactor shapes.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.11
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• pp.745-753
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• 2016

Micro methanol-steam reformer for fuel cell can effectively produce hydrogen as reforming response to steam takes place in low temperature (less than $250^{\circ}C$). This study conducted numerical research on this reformer. First, study set wall temperature of the reformer at 100, 140, 180 and $220^{\circ}C$ while methanol conversion efficiency was set in 0, 0.072, 3.83 and 46.51% respectively. Then, porosity of catalyst was set in 0.1, 0.35, 0.6 and 0.85 and although there was no significant difference in methanol conversion efficiency, values of pressure drop were 4645.97, 59.50, 5.12 and 0.45 kPa respectively. This study verified that methanol-steam reformer rarely responds under the temperature of $180^{\circ}C$ and porosity does not have much effect on methanol conversion efficiency if the fluid flowing through reformer lowers activation energy by sufficiently contacting reformer.

• 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.

• Clean Technology
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• v.19 no.1
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• pp.51-58
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• 2013

In this study, kinetics data was obtained for steam reforming reaction of ethane over the nickel catalyst. The variables of steam reforming reaction were reaction temperature, partial pressure of ethane, and mole ratio of steam and ethane. Parameters for the power rate law kinetic model and the Langmuir-Hinshelwood model were obtained from the kinetic data. Also, sizing of steam reforming reactor was performed by using PRO/II simulator. For the steam reforming reaction of ethane, Langmuir-Hinshelwood model determining the reaction rate by the surface reaction was better suited than a simple power rate law kinetic model. On water-gas-shift reaction, power rate law kinetic model was well fitted to the kinetic data. Reactor size can be calculated for production of hydrogen through PRO/II simulation.

• Applied Chemistry for Engineering
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• v.29 no.2
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• pp.209-214
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• 2018

In this paper, the techno-economic analysis of glycerol steam reforming for $H_2$ production capacity of $300m^3\;h^{-1}$ was carried out. The process of glycerol steam reforming was constructed by using Aspen $HYSYS^{(R)}$, a commercial process simulator, and parametric studies for the effect of the operating temperature on $H_2$ production was performed. Moreover, the economic analysis was conducted through an itemized cost estimation, sensitivity analysis (SA) and cash flow diagram (CFD), and the unit $H_2$ production cost was 5.10 $ ${kgH_2}^{-1}$ through the itemized cost estimation of glycerol steam reforming for $H_2$ production capacity of $300m^3\;h^{-1}$. SA was employed to identify key economic factors and various economic indicators such as net present value (NPV), discounted payback period (DPBP), and present value ratio (PVR) were found according to $H_2$ selling price using CFD.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.560-567
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• 2016

In this study, we characterized steam reforming reactions and surface of $Ni/Al_2O_3$ catalysts. Ni-Mo based catalysts were prepared by loading Mo as the co-catalyst and reaction activities of the Ni-Mo based catalysts were compared with those of Ni-based catalysts. Through the $H_2$-TPR and XPS analysis it was confirmed that this characteristic efficiency. $O_2$-TPO analysis was performed to examine the deposition characteristics, bonding structures and evaporation characteristics of carbon deposited on the surface of catalysts after long run experiments were performed for steam reforming reactions. As the results, it was found that durability was improved in Ni-Mo based catalysts inhibiting formation of graphitic carbon species which reduced reaction activities of the catalysts by strongly interacting with Ni in the steam reforming reaction.

• Applied Chemistry for Engineering
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• v.23 no.2
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• pp.204-209
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• 2012

In this study, kinetics data was obtained for steam reforming reaction of ethane over the commercial ruthenium catalyst. The variables of ethane steam reforming were the reaction temperature, partial pressure of ethane, and steam/ethane mole ratio. Parameters for the power rate law kinetic model and the Langmuir-Hinshelwood model were obtained from the kinetic data. Also, sizing of steam reforming reactor was performed by using PRO/II simulator. The reactor size calculated by the power rate law kinetic model was bigger than that of using the Langmuir-Hinshelwood model for the same conversion of ethane. Reactor size calculated by the Langmuir-Hinshelwood model seems to be more suitable for the reactor design because the Langmuir-Hinshelwood model was more consistent with the experimental results.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.230.2-230.2
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• 2010

천연가스 수증기 개질 반응에 사용되는 펠릿 촉매의 단점인 열 및 물질 전달 제한, 낮은 effectiveness factor, 압력강화와 channeling 등의 문제점을 해결 하고자 모노리스 형태의 금속 구조체 촉매를 본 연구에 적용 하였다. Fecralloy 재질의 금속 구조체에 Ni 촉매를 워시코팅 (wash coating) 하여 제조 하였으며, 이를 천연가스 수증기 개질 반응에 적용하여 수소를 생산하였다. 실험 조건으로는 S/C ratio를 3으로 고정하여 온도를 $600^{\circ}C{\sim}800^{\circ}C$로 변화 시켰으며, GHSV $3000{\sim}30000h^{-1}$에서 진행 되었다. 구조체 촉매 코팅에 사용된 Ni 촉매의 BET, TPR, H2-chemisorption, SEM, EDS의 특성분석을 수행 하였다. 온도별 테스트에서 모노리스 형태의 금속 구조체 촉매가 펠릿 형태의 촉매에 비해 우수한 열전달 효과로 인해 낮은 퍼니스 온도와 높은 반응 활성을 나타내었으며, GHSV 변화에 따른 성능평가 결과도 15wt% $Ni/MgAl_2O_4$펠릿 촉매와 비교하여 금속 구조체 촉매가 높은 활성을 보였다.

• Journal of the Korean Solar Energy Society
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• v.21 no.4
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• pp.29-35
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• 2001

The chemical heat storage as the one way of utilization for high temperature solar energy was considered. The stram reforming reaction of methane was chosen for endothermic reaction. The reactor was made of stainless steel tube and it's dimension was 0.635 cm I.D. and 30 cm long, coiled tube because of the geometry requirement of solar receiver The effects of space velocity and reactants mole ratio on the methane conversion and CO selectivity were examined. From the experimental results, the optimum steam/methane mole ratio was determined.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.4
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• pp.388-396
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• 2011

The strengthened regulations for atmospheric emissions from ships have caused a necessity of new, alternative power system in ships for the low pollutant emissions and the high energy efficiency. Recently, new kinds of propulsion power system such as fuel cell system, which use hydrogen as an energy source, have been sincerely considered. Fuel conversion system to hydrogen is an essential part for fuel cell ship. We have investigated thermodynamically the steam reforming characteristics of hydrocarbons and alcohols for the fuel conversion systems.