• 한국연소학회지
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• 제20권2호
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• pp.36-39
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• 2015

The combustion characteristics of metal fiber burner fueled natural gas with tail gas produced from reforming process were analyzed on the point of flame stability and excess air conditions. Also, it was analyzed the effect of energy efficiency improvement due to decrease the fuel input in reforming system by using residue gases. As a results, it was confirmed that tail gas including hydrogen, CO and $CO_2$ could be directly injected without any change of air control system in natural gas burner and also energy efficiency was increased up to 30% maintained stable combustion.

• 한국유체기계학회 논문집
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• 제14권6호
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• pp.61-67
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• 2011

The study is to analyze the chemical and heat-flow reactions in the hydrogen generation unit(autothermal reformer), using computational numerical tools. Autothermal reformer(ATR) is involved in complex chemical reaction, mass and heat transfer due to exothermic and endothermic reactions. Therefore it is necessary to reveal the effects of various operation parameters and geometries on the ATR performance by using numerical analysis. Numerical analysis needs to dominant chemical reactions that includes Full Combustion(FC) reaction, Steam Reforming(SR) reaction, Water-Gas Shift(WGS) reaction and Direct Steam Reforming(DSR) reaction. The objective of the study is to improve theoretically the reformer design capability for the goal of high hydrogen production in the autothermal reformer using methane. Hydrogen production reached maximum in a certain value of Oxygen to Carbon Ratio(OCR) or Steam to Carbon Ratio(SCR). When the longitudinal distance to dimeter ratio(L/D) is increased, hydrogen production increases.

• 청정기술
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• 제23권2호
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• pp.213-220
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• 2017

HY 제올라이트에 담지된 Ni 촉매 및 Mg, Ca, K 그리고 Mn 등이 조촉매로 함께 담지된 Ni/HY 촉매상에서 메탄의 건식 개질 반응을 수행하였다. 촉매는 초기 함침법으로 제조하였으며 제조된 촉매는 XRD, BET, SEM 및 TGA 분석을 통하여 반응 전후 의 촉매 변화를 고찰하였다. Ni의 담지량이 증가함에 따라 메탄의 전환율 및 생성물의 수율이 증가하였으며 Ni의 담지량이 13 wt% 일 때 메탄의 전환율이 최대를 나타내었다. Mg를 조촉매로 함께 담지하였을 때 촉매의 탄소에 대한 저항성이 크게 증가하였으며 이에 따라 촉매의 장기 안정성이 크게 향상되었다. 이는 조촉매로 담지된 Mg가 Ni의 입자 크기를 작게 하여 Ni의 분산도를 향상시키고 촉매의 비활성화를 방지하기 때문인 것으로 나타났다.

• 한국수소및신에너지학회논문집
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• 제30권3호
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• pp.209-219
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• 2019

Methanol is a liquid fuel which could also be produced from renewable energy sources and has appreciably high energy density. In this work, we investigated the application of $Ce_{0.9}Gd_{0.1}O_{2-x}$ supported Cu and Ni catalysts for hydrogen production via methanol steam reforming. Catalysts were synthesized by solution combustion synthesis. The prepared catalysts with various active materials and Cu loading amounts were tested in a reactor at $200-300^{\circ}C$, 0-5 barg range and steam to methanol molar ratio was 1.5. The catalytic properties of Cu and Ni were compared, and the catalytic performance was shown to depend on the amounts of metal loading and operating conditions such as reaction temperature and pressure.

• 한국수소및신에너지학회논문집
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• 제30권2호
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• pp.111-118
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• 2019

Greenhouse gas emissions have a profound effect on global warming. Various environmental regulations have been introduced to reduce the emissions. The largest amount of greenhouse gases, including carbon dioxide, is produced in the steel industry. To decrease carbon dioxide emission, hydrogen-based iron oxide reduction, which can replace carbon-based reduction has received a great attention. Iron production generates various by-product gases, such as cokes oven gas (COG), blast furnace gas (BFG), and Linz-Donawitz gas (LDG). In particular, COG, due to its high concentrations of hydrogen and methane, can be reformed to become a major source of hydrogen for reducing iron oxide. Nevertheless, continuous COG cannot be supplied under actual operation condition of steel industry. To solve this problem, this study proposed to use two alternative COG-based fuel mixtures; one with natural gas and the other with biogas. Reforming study on two types of mixed gas were carried out to evaluate catalyst performance under a variety of operating conditions. In addition, methane conversion and product composition were investigated both theoretically and experimentally.

• Korean Chemical Engineering Research
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• 제61권2호
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• pp.328-339
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• 2023

Methanol steam reforming (MSR) is a promising method for hydrogen supplying as a critical step in hydrogen fuel cell commercialization in mobile applications. Modelling and understanding of the reactor behavior is an attractive research field to develop an efficient reformer. Three-layer feed-forward artificial neural network (ANN) and Box-Behnken design (BBD) were used to modelling of MSR process using the Cu-SiO₂ aerogel catalyst. Furthermore, impacts of the basic operational variables and their mutual interactions were studied. The results showed that the most affecting parameters were the reaction temperature (56%) and its quadratic term (20.5%). In addition, it was also found that the interaction between temperature and Steam/Methanol ratio is important on the MSR performance. These models precisely predict MSR performance and have great agreement with experimental results. However, on the basis of statistical criteria the ANN technique showed the greater modelling ability as compared with statistical BBD approach.

• 공업화학
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• 제17권1호
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• pp.87-92
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• 2006

Ru이 첨가된 $Ni/Al_2O_3$ 촉매 상에서의 메탄 수증기 개질 반응을 수행하였다. 반응 전에 $H_2$를 사용한 전처리가 필요한 $Ni/Al_2O_3$ 촉매에 비해, $Ru/Ni/Al_2O_3$ 촉매는 별도의 전처리 과정이 없이도 우수한 반응 활성을 나타내었다. $CH_4-TPR$과 반응 후 촉매에 대한 $H_2-TPR$ 결과, 메탄의 분해반응에 의한 $RuO_x$의 환원이 저온($220^{\circ}C$)에서부터 진행되며, 환원된 Ru이 NiO의 환원을 촉진하게 되어 자발적인 환원이 일어나게 된다는 것을 알 수 있었다. 금속 입자의 분산도를 높이기 위하여 $Ru/Ni/Al_2O_3$ 촉매를 $45^{\circ}C$에서 2 h 동안 $7M\;NH_4OH$ 수용액에 담근 후 소성하여 반응을 수행하였다. $NH_4OH$ 수용액으로 처리한 $Ru/Ni/Al_2O_3$ 촉매는 상대적으로 더 높은 반응 활성을 나타내었으며, $H_2$-화학흡착과 XRD, XPS 분석 결과로부터 입자크기가 감소하고 금속의 분산도가 향상되었음을 확인할 수 있었다. $NH_4OH$ 수용액에 의한 촉매의 고분산을 이용하여 Ru의 함량을 감소시켜 소량의 첨가로 높은 반응 활성을 보이고자 하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.129.1-129.1
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• 2010

Since the commencement of the fuel cell business in 2007, POSCO POWER has been the major supplier of the MCFC (Molten Carbonate Fuel Cell), which is the most commercialized stationary fuel cell system in the world. With its quite, yet active movement, more than 20MW MCFC systems have been installed and are operating in Korea. While trying to localize the components and set up a firm supply chain in Korea to provide more reliable and cost-competitive products to its customers, POSCO POWER is also devoting itself to developing new MCFC application products. One such product is a back-up power system, in which a back-up algorithm is embedded to the present system so that the product can work as a back-up generator in case of grid failure. The technology to enhance load following capability of a stack module is also being developed with the back-up algorithm. Another example is a building application, the goal being to make the present Sub-MW product suitable for urban area. For this, downsizing and modularization are the main R&D scope. The project for developing ship service fuel cell for APU application will launch soon as well. In the project, a system which can operate in marine environment, and reforming technology for liquid logistic fuel will be developed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.1997-2002
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• 2007

The reformer is one of the most important chemical processes for the production of high purity hydrogen from fossil fuel. This study compares zero-dimensional model with CFD models for reaction analysis of methane-steam reformer. The zero-dimensional model is an empirical equation, however CFD model uses reactions of Arrhenius type. Because the reaction coefficients of the steam-methane catalytic reforming have not been reported before in the form of Arrhenius type, the present study aims to find the appropriate reaction coefficients. The used CFD code is Fluent 6.2 version. Several models are compared for the case of various operating temperature, mass of catalyst and steam to methane ratio.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3230-3235
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• 2007

Design performances of various configurations of the PEMFC/GT hybrid systems have been evaluated. Based on PEMFC adopting steam reforming, various system configurations (one ambient pressure configuration and three different pressurized configurations) were designed and their performances were compared. Their Performances are also compared with the reference PEMFC system. Influences of turbine inlet temperature, pressure ratio on the hybrid systems performance were investigated and design ranges exhibits better efficiency than the PEMFC system were presented. One of the pressurized system may have much higher efficiency than the PEMFC system, while other systems hardly provide efficiency upgrade.