• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.153-156
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• 2009

Low temperature methane steam reforming to produce $H_2$ for fuel cells has been calculated thermodynamically considering both heat loss of the reformer and unreacted $H_2$ in fuel cell stack. According to the thermodynamic equilibrium analysis, it is possible to operate methane steam reforming at low temperatures. A scheme for the low temperature methane steam reforming to produce $H_2$ for fuel cells by burning both unconverted $CH_4$ and $H_2$ to supply the heat for steam methane reforming has been proposed. The calculated value of the heat balance temperature is strongly dependent upon the amount of unreacted $H_2$ and heat loss of the reformer. If unreacted $H_2$ increases, less methane is required because unreacted $H_2$ can be burned to supply the heat. As a consequence, it is suitable to increase the reaction temperature for getting higher $CH_4$ conversion and more $H_2$ for fuel cell stack. If heat loss increases from the reformer, it is necessary to supply more heat for the endothermic methane steam reforming reaction from burning unconverted $CH_4$, resulting in decreasing the reforming temperature. Experimentally, it has been confirmed that low temperature methane steam reforming is possible with stable activity.

• 한국연소학회:학술대회논문집
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• 2005.10a
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• pp.64-68
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• 2005

Methane reforming processes to obtain hydrogen were investigated experimentally by using atmospheric plasma source. Among possible reforming processes, such as a $CO_2$ reforming(dry reforming), a partial oxidation (POx), a steam reforming(SR), and a steam reforming with oxygen(SRO or auto-thermal reforming), partial oxidation and the steam reforming with oxygen were considered. We choose a rotating arc plasma as an atmospheric plasma source, since it shows the best performances in our preliminary tests in terms of a methane conversion, a hydrogen production, and a power consumption. Then, the effects of a feeding flow-rate, an electrical power input to a plasma reaction, an $O_2/C$ ratio and a steam to carbon ratio in the case of SRO on the reforming characteristics were observed systematically. As results, at a certain condition almost 100% of methane conversion was obtained and we could achieve the same hydrogen production rate by consuming a half of electrical power which was used by the best results for other researchers.

• Journal of Energy Engineering
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• v.22 no.2
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• pp.226-236
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• 2013

The heat distribution and internal flow from the efficiency of actual reformer and specification variation, using the computer simulation and experiment about the steam methane reforming reaction which uses the high temperature reformer. Reaction model from steam refoemer uses the steam response model developed by Xu & Froment.As result we supposed the chemical react Steam Reforming(SR), Water Gas Shift(WGS), and Direct Steam Reforming(DSR) from the inner high temperature reformer dominates the response has dissimilar response. According to result of steam methane reforming reaction exam using high temperature reformer, we figured out when Steam Carbon Ratio(SCR) increase, number of hydrogen yield increases but methane decreases. When comparing and examining between design with one inlet and two inlet, result came out one inlet design is more outstanding at thermal distribution and internal flow, hydrogen yield in one inlet design than two inlet design.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.477-480
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• 2006

In this study, we investigated operating characteristics of the LNG burner for steam methane reforming. The developed LNG burner and catalytic reactor to supply an efficient heat transfer between the combustion gas and catalyst got a good response of various operating load within 5-7 minute and high efficiency for steam methane reforming as a conversion of methane over 90%. We calculated the volume of catalyst for $1Nm^3/hr$ steam LNG reforming as $211cc/(Nm^3/hr\;H_2)$ and got the operating condition and design data of the burner and steam reforming for LNG.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.172-175
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• 2006

Steam reforming of methane using Xe-arc solar simulator was studied for converting solar radiation into energy foam that one can readily utilize. The Xe-arc lamp produce a spectrum similar to that of the sun. SiC ceramic foam, resist high temp.$(>900^{\circ}C)$, is used to catalytically active foam absorber, and to support of reforming catalyst. The catalyst on the surface of foam were directly irradiated with solar simulated xe-light in order to carry out the steam reforming of methane. The reactor was made of stainless steel and quartz window was located on a place of the xe-light irradiation and temperature was controlled using K-type thermocouple in contact with catalyst located inside the reactor. The result show that a possibility of solar reforming using catalytically active foam absorber is exist.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1323-1327
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• 2001

The catalyst Ni/MgO (Ni : 15 wt%) has been applied to methane reforming reactions, such as steam reforming of methane (SRM), partial oxidation of methane (POM), and oxy-steam reforming of methane (OSRM). It showed high activity and good stability in all the reforming reactions. Especially, it exhibited stable catalytic performance even in stoichiometric SRM (H2O/CH4 = 1). From TPR and H2 pulse chemisorption results, a strong interaction between NiO and MgO results in a high dispersion of Ni crystallite. Pulse reaction results revealed that both CH4 and O2 are activated on the surface of metallic Ni over the catalyst, and then surface carbon species react with adsorbed oxygen to produce CO.

• Journal of Hydrogen and New Energy
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• v.15 no.4
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• pp.301-308
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• 2004

The methane reforming with $CO_2$ and steam for manufacture of synthesis gas over $Ni/ZrO_2$ catalyst was investigated. Mixed reforming carried out $CO_2$ dry reforming with $O_2$ and steam for development of DME process in pilot plant. To improve a catalyst deactivation by coke formation, the mixed reforming added carbon dioxide and steam as a oxidizer of the methane reforming was suggested. The result of experiments over commercial catalyst in $CO_2$ dry reforming has shown that the catalyst activity decrease rapidly after 20 hours. In case of $NiO-MgO/Al_2O_3$ catalyst, the deactivation of 20 percent after 30 hours was occurred. The activity of Ni/C catalyst still was not decreased dramatically after 100 hours. The effect of $H_2$ reforming with steam over $Ni/CO_2$ catalyst obtained the optimal conversion of methane and carbon dioxide, and could be produced synthesis gas at ratio of $H_2/CO$ under 1.5.

• Journal of the Korean Solar Energy Society
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• v.25 no.4
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• pp.13-19
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• 2005

The reaction of steam reforming of methane with commercial catalysts was conducted for thermochemical heat storage. The reaction conditions were investigated for temperature range of 700 to $900\;^{\circ}C$ and steam to carbon mole ratios between 3.0 and 5.0. The reactor was made of stainless steel and it's dimension was 12 cm inside diameter and 6cm long. The effects of space velocity and reactants mole ratio and temperature on the methane conversion and CO selectivity were examined. Optimum reaction condition was determined. There was not a significant difference of methane conversion and CO selectivity compared to conventional reactor.

• Journal of the Korean Solar Energy Society
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• v.27 no.1
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• pp.75-81
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• 2007

Steam reforming of methane using Xe-arc solar simulator was studied for the application of concentrated solar energy into chemical reaction. The reactor, a volumetric absorber, consisted of a porous ceramic foam disk coated with commercial reforming catalyst. Operating temperature was in the range of $450\;-\;550^{\circ}C$ and the excess steam ratio to methane was from 3.0 to 5.0. At the steady-state condition, the conversion of methane Increased with temperature in the range of 15 % - 30 % and the experimentally determined conversion was found to be close to theoretical equilibrium conversion. It was also found that the CO selectivity slightly decreased with excess steam ratio. Finally, the conversion of methane decreased significantly with space velocity of reactants.

• Journal of the Korean Ceramic Society
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• v.52 no.5
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• pp.325-330
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• 2015

Performance of solid oxide fuel cells (SOFCs), in comparison with that under hydrogen fuel, were investigated under direct internal reforming conditions. Anode supported cells were fabricated with an Ni+YSZ anode, YSZ electrolyte, and LSM+YSZ cathode for the present work. Measurements of I-V curves and impedance were conducted with S/C (steam to carbon) ratio of ~ 2 at $800^{\circ}C$. The outlet gas was analyzed using gas chromatography under open circuit condition; the methane conversion rate was calculated and found to be ~ 90% in the case of low flow rate of methane and steam. Power density values were comparable for both cases (hydrogen fuel and internal steam reforming of methane), and in the latter case the cell performance was improved, with a decrease in the flow rate of methane with steam, because of the higher conversion rate. The present work indicates that the short-term performance of SOFCs with conventional Ni+YSZ anodes, in comparison with that under hydrogen fuel, is acceptable under internal reforming condition with the optimized fuel flow rate and S/C ratio.