• Journal of Advanced Marine Engineering and Technology
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• 제40권7호
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• pp.569-573
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• 2016

온실가스 및 대기오염물질 배출 규제는 고효율 및 친환경에 적합한 새로운 선박용 동력장치의 필요성을 제기하고 있다. 최근 이와 같은 문제들을 근본적으로 해결하기 위한 지속가능한 방법으로서 연료전지를 선박의 동력발생장치로 도입하고자 하는 검토가 진행되고 있다. 본 논문은 중대형 선박 적용으로 메탄 개질용 수증기를 내부에서 재순환시키는 고체산화물형 연료전지시스템의 효용성을 외부수증기 공급 방식과 비교하여 분석한 것이다. 그 결과로 재순환수증기 연료개질방식이 셀 전압은 약간 낮게 유기되나 시스템의 전기적 효율은 다소 높아진다는 것을 알 수 있었다.

• 한국가스학회:학술대회논문집
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• 한국가스학회 2005년도 추계학술발표회 논문집
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• pp.131-134
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• 2005

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.793-795
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• 2002

• 한국수소및신에너지학회논문집
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• 제17권2호
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• pp.166-173
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• 2006

Catalytic reforming of $CO_2$ by $CH_4$ over Ni-YSZ based catalysts was investigated to produce syngas as raw material of high valued chemicals and develop high performance catalyst electrode for an internal reforming of $CO_2$ in SOFC system. Ni-YSZ based catalysts were prepared using physical mixing and maleic acid methods to improve catalytic activity and inhibition of carbon deposition. The catalysts before and after the reaction were characterized by $N_2$ physisorption, TPR(temperature programed reduction), XRD and impedance analyzer. The conversions for $CO_2$ and $CH_4$ over Ni-MgO catalyst showed 90% but much amount of carbon deposition was detected on catalyst surface. On the other hand, the conversions for $CO_2$ and $CH_4$ over NiO-YSZ-$CeO_2$ catalyst showed 100% and 85% respectively, and carbon deposition on catalyst surface was inhibited under the tested condition. It was concluded that NiO-YSZ-$CeO_2$ catalyst is a promising candidate for the catalytic reforming of $CO_2$ and the internal reforming in SOFC system.

• 에너지공학
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• 제16권2호
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• pp.58-63
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• 2007

최근 신 고유가 시대를 맞이하여 천연가스를 이용한 합성석유 제조기술 개발의 중요성이 점차로 부각되고 있는 상황이다. GTL(Gas-to-Liquids) 공청은 현재의 고유가 상황에서 경쟁력 있는 사업 분야를 제공 할 것으로 분석되고, GTL 제품은 환경오염물질이 거의 없어 21 세기의 환경규제 강화 추세에 효과적으로 대응할 수 있는 청정연료이다. GTL 공정은 크게 천연가스의 주성분인 메탄의 리포밍 반응을 거쳐 합성가스 ($CO+H_{2}$)를 제조하는 단계, 이 합성가스로부터 FT 합성반응을 통하여 액체 합성원유를 제조하는 단계, 합성원유를 개질하는 단계 (수첨분해/수첨이성질화)로 이루어진다. 본 총설에서는 GTL 기술의 개요와 세계적인 개발 동향을 천연가스 reforming 기술과 FT 합성유 제조 기술에 중점을 두고서 소개하고자 한다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.511-512
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• 2008

For the $CO_2$ reforming of $CH_4$, Ni catalyst was supported on La-hexaaluminate or on $\gamma$-$Al_2O_3$. The catalytic activities of Ni/La-hexaaluminate catalysts were measured at $700^{\circ}C$ using gas chromatography (GC) for 72 h, and the reaction was maintained up to 72 hfor the investigation of catalyst deactivation. The surface of each catalyst after 72 h reaction was investigated using SEM and TEM, and the composition of the carbon deposits was investigated by using EA, TPO and TGA. Ni/La-hexaaluminate shows higher resistance to coke deposition than conventional Ni/$Al_2O_3$ which seems to be due to strong interaction between Ni and the support material. As a result of the reforming reaction, various types of carbon deposits were created on catalyst surface and the amounts of them were much smaller in the case of La-hexaaluminate than on $Al_2O_3$.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.247-250
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• 2008

Biomass gasification is a promising technology for producing a fuel gas which is useful for power generation systems. In biomass gasification processes, tar formation often causes some problems such as pipeline plugging. Thus, proper tar treatment is necessary. So far, nickel (Ni)-based catalysts have been intensively studied for the catalytic tar removal. However, the deactivation of Ni-based catalysts takes place because of coke deposition and sintering of Ni metal particles. To overcome these problems, we have been using ruthenium (Ru)-based catalyst for tar removal. It is reported by Okada et al., that a Ru/$Al_2O_3$ catalyst is very effective for preventing the carbon deposition during the steam reforming of hydrocarbons. Also, this catalyst is more active than the Ni-based catalyst at a low steam to carbon ratio (S/C). Benzene was used for the tar model compound because it is the main constituent of biomass tar and also because it represents a stable aromatic structure apparent in tar formed in biomass gasification processes. The steam reforming process transforms hydrocarbons into gaseous mixtures constituted of carbon dioxide ($CO_2$), carbon monoxide (CO), methane ($CH_4$) and hydrogen ($H_2$).

• 한국가스학회지
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• 제9권4호
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• pp.44-49
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• 2005

본 연구에서는 Steam Reforming수소 제조설비에 대한 안전성 평가를 수행하여 설비의 위험성을 체계적으로 검토하였다 안전성 평가 방법으로는 정성적 안전성 기법인 Hazard & Operability Analysis와 Failure Mode & Effect Analysis를 사용하였다. HAZOP을 통하여 수소 제조설비의 flow, pressure, temperature 등의 주요 parameter들에 대하여 의미 있는 guide word를 적용하여 비정상 상태(deviation)를 만들어 단계별로 공정상의 인간 실수나 잘못된 운전 등의 잠재 위험을 분석하였다. FMEA를 이용하여 설비 내 장치의 파손 및 기능 실패 등 주로 부품의 불량이나 고장 등에 대한 분석을 하여 그에 따른 영향 및 대처방안을 제시하였고, RPN값 계산을 통하여 상대적 위험순위를 결정하여 보았다.

• 대한기계학회논문집B
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• 제32권7호
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• pp.558-565
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• 2008

Solid oxide fuel cell(SOFC) has a higher fuel flexibility than low temperature fuel cells, such as polymer electrolyte fuel cell(PEMFC) and phosphoric acid fuel cell(PAFC). SOFCs also use CO and $CH_4$ as a fuel, because SOFCs are hot enough to allow the CH4 steam reformation(SR) reaction and water-gas shift(WGS) reaction occur within the SOFC stack itself. Diesel is a good candidate for SOFC system fuel because diesel reformate gas include a higher degree of CO and $CH_4$ concentration than other hydrocarbon(methane, butane, etc.) reformate gas. Selection of catalyst for autothermalr reforming of diesel was performed in this paper, and characteristics of reforming performance between packed-bed and microchannel catalyst are compared for SOFC system. The mesh-typed microchannel catalyst also investigated for diesel ATR operation for 1kW-class SOFC system. 1kW-class diesel microchannel ATR was continuously operated about 30 hours and its reforming efficiency was achieved nearly 55%.

• 대한기계학회논문집B
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• 제32권7호
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• pp.497-503
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• 2008

Hydrogen is considered as a fuel of the future for its renewability and environmental compatibility. The reforming of hydrocarbon fuels is currently the most important source of hydrogen, which is expected to continue for next several decades. In this study, extensive CFD simulations on the steam-methane reforming process were conducted to study the performance of four reaction models, i.e. three Arrhenius-type models and a user-defined function (UDF) model. The accuracies of different reaction models for various operating temperatures and steam carbon ratios (SCRs) were evaluated by comparing their CFD results with zero-dimensional intrinsic model of Xu and Froment. It was found that the UDF model generally produced more accurate results than Arrhenius-type models. However, it was also shown that Arrhenius-type models could be made sufficiently accurate by choosing appropriate reaction coefficients, and thus could also be useful for the simulation of the steam-methane reforming process.