• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.19-22
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• 2007

In this study, we investigated operating characteristics of natural gas fuel processor for polymer electrolyte membrane fuel cells (PEMFCs). The fuel processor consists of a natural gas reformer, a water-gas shift reactor, a heat-exchanger and a burner, in which the overall integrated volume is exactly(exceptionally) small, namely, about 10L except outer insulation. The producted hydrogen is $1Nm^3/hr$ and the maximum thermal efficiency is ${\sim}76%$(low heating value) at full operating load. A compact and highly efficient $1Nm^3/hr$ class natural gas fuel processor was developed at UNISON is an advantage for application in residential PEMFCs co-generation systems.

• Journal of the Korean Institute of Gas
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• v.14 no.4
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• pp.51-55
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• 2010

The global activities to reduce the $CO_2$ emission as a greenhouse gas have been various efforts. Under this circumstance, small and medium sized gas field containing $CO_2$ to develop as LNG is not economic feasibility. Particularly, for the separation of $CO_2$ in gas field, separation facilities should be installed to add. This is and increase in plant construction cost and separated $CO_2$ emission into the atmosphere is not the result of greenhouse gas reduction. When the uneconomic gas field apply the KOGAS DME process, the gas field containing $CO_2$ can be increase economic feasibility because of natural gas and $CO_2$ can be use to resource gas. The Tri-reformer produced syngas as H2 and CO in KOGAS DME process and the resource gases are natural gas, steam, oxygen and $CO_2$. The $CO_2$ is used as raw material gases from recover $CO_2$ in DME process. In this study, we investigated range of application of $CO_2$ in gas field.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2886-2891
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• 2008

The purpose of this study is to develop a highly-efficient and compact steam reformer for PEMFC changing the burner types. For the purpose some of the Can type flat burners were adopted and the results were compared with 'O' company's typical cylinderical flat burner. We used commercial STAR-CD tools for numerical calculation. We found the optimum Can type STR burner and this type of burner was highly efficient comparing with typical burner.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.25-28
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• 2006

수소는 청정에너지로서 미래에너지의 대안으로 여겨지고 있기 때문에 수소에너지 관련 기술은 미래 국가 경쟁력을 좌우할 것으로 예상되며 이러한 수소에너지의 핵심인 수소스테이션 관련 기술은 국가연료전지 시장을 비롯한 수소자동차 사업 전반에 커다란 영향을 미칠 것으로 예상되고 있다. 이에 따라 전 세계적으로 수소에너지를 차세대 에너지원으로 개발하기 위하여 전력을 다하고 있으며, 수소연료전지자동차 개발과 아울러 수소스테이션 개발에 대한 인프라 구축 및 실증연구가 본격적으로 이루어지고 있다. 국내에서도 가스공사를 비롯한 에너지 관련 기업에서 수소스테이션 건설이 추진되고 있으며, 본 연구에서도 수소인프라 구축의 일환으로 추진되고 있는 수소스테이션 개발 현황에 대하여 논의하고자 한다.

• Journal of Hydrogen and New Energy
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• v.23 no.5
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• pp.545-550
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• 2012

This work is for the design study of natural gas reformer (40 $m^3/hr$ over). We used experimental kinetic data from literature. After that, we set up theoretical model based on experimental reaction kinetic data. The shape of reactor is 1.7 m long and 200 mm dia. with cylinder geometry. Volume of reactor is 53.4 liter. Average flow velocity of gases in the reactor has been determined 0.272 m/sec and residence time is 9.26 sec. Reaction temperature is $850^{\circ}C$, with pressure 9.3 Bar. Used natural gas volume is about 9.21 $m^3/hr$. Produced hydrogen is 43.7 $m^3/hr$ with no change of pressure. Unreacted natural gas is 0.09 $m^3/hr$ and the amount of steam is 26.9 $m^3/hr$. Steam to $CH_4$ (s/c ratio) is 2.91. Reforming reaction take place from the reactor entrance to 120 cm region of cylinder type reactor. After the entrance of reacting gases to 120 cm region, the reaction reaches equilibrium which is close to products. This study can be applicable to design various reactors. Output data is in good agreements with the data in literatures1).

• Journal of Hydrogen and New Energy
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• v.30 no.6
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• pp.485-489
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• 2019

Hydrogen is known to be a clean fuel which does not generate a green house gas during the combustion. However, about 8 kg of carbon dioxide is generated during the course of producing 1 kg of hydrogen through reforming, water gas shift reaction and pressure swing adsorption in order to obtain a high purity hydrogen over 99.999% by volume. In this work, carbon dioxide generation is estimated according to four kinds of natural gas compositions supplied by Korea Gas Corporation and regarding natural gas as pure methane. For the simulation of the modeling, PRO/II with PROVISION V10.2 at AVEVA was utilized and Peng-Robinson equation of state with Twu's alpha function was selected.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.9 s.252
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• pp.850-857
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• 2006

Hydrogen production using current fueling facilities is essential for near-term applications of fuel cells. A preliminary process for developing a natural gas autothermal reforming (ATR) reactor for fuel cells is presented in this paper. A experimental reactor for methane ATR was constructed and used for characterization of Jin reactor. Temperature profiles of the reactor were observed, and reformed gas compositions were analyzed to evaluate efficiency, conversion and reaction heat with varying amounts of $O_2/CH_4$ at selected furnace temperature and $H_2O/CH_4$. The amount of $O_2/CH_4$ showed strong offsets on reactor temperature, efficiency and conversion indicating that $O_2/CH_4$ is a crucial operation condition. Operation conditions which result in thermal neutrality of ATR reactor system were determined for two cases of an ATR system based on the estimation of enthalpy difference between reactants of assumed inlet temperatures and the products from experimental results. The determined conditions for thermally neutral operations could be used for guidelines to design reformers and for determining the operation parameters of a self sustaining ATR reactor.

• Journal of Hydrogen and New Energy
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• v.33 no.6
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• pp.819-826
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• 2022

Fuel cell systems are being supplied to households and buildings to reduce greenhouse gases. The fuel cell systems have problems of high cost and slow startup due to fuel processors. Greenhouse gas reduction of the fuel cell systems is also limited by using natural gas. The problems can be solved by using a hydrogen generator consisting of a reformer and pressure swing adsorption (PSA). However, part load operation of the hydrogen generator is required depending on the hydrogen consumption. In this paper, PSA operation strategies are investigated for part load of the hydrogen generator. Adsorption and purge time were changed in the range of part load ratio between from 0.5 to 1.0. As adsorption time increased, hydrogen recovery increased from 29.09% to 48.34% at 0.5 of part load ratio. Hydrogen recovery and hydrogen purity were also improved by increasing adsorption and purge time. However, hydrogen recovery dramatically decreased to 35.01% at 0.5 of part load ratio.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.4 no.2
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• pp.1-6
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• 2008

Very High Temperature Gas Cooled Reactor (VHTR) has been selected as a high energy heat source for nuclear hydrogen generation. The VHTR can produce hydrogen from heat and water by using a thermo-chemical process or from heat, water, and natural gas by steam reformer technology. A co-axial double-tube primary hot gas duct (HGD) is a key component connecting the reactor pressure vessel and the intermediate heat exchanger (IHX) for the VHTR. In this study, a preliminary design analysis for the primary HGD of the nuclear hydrogen system was carried out. These preliminary design activities include a determination of the size, a strength evaluation and an appropriate material selection. The determination of the size was undertaken based on various engineering concepts, such as a constant flow velocity model, a constant flow rate model, a constant hydraulic head model, and finally a heat balanced model.

• Journal of Institute of Convergence Technology
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• v.12 no.1
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• pp.19-23
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• 2022

Interest in hydrogen production to respond to climate change is increasing. Until now, hydrogen has been mainly produced through the SMR (Steam Methane Reforming) process using natural gas. A large amount of CO₂ is emitted in the hydrogen production process through SMR, and the gas flow including CO₂ generated in the SMR process has different characteristics for each emission source, so it is important to apply a suitable CO₂ capture process. In the case of PSA tail gas or synthesis gas, the applicability of an amine-based process has been confirmed or demonstrated close to a commercial level. However, in the case of the flue gas generated from the reformer, it is still difficult to apply the conventional amine-based process because the partial pressure of CO₂ is relatively low. Energy-saving innovative absorbents such as phase separation absorbents can be a solution to these difficulties.