• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.235-236
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• 1999

보일러와 같은 고정원에서 배출되는 질소산화물을 제거하기 위한 후처리 기술인 선택적촉매환원공정(SCR:Selective Catalytic Reduction)은 안정적이며 탈질효율이 높아 상업적으로 가장 많이 이용되고 있다(Bosch, 1988). 본 연구팀은 가격 및 성능 측면에서 외국산 상업용 촉매와 경쟁할 수 있는 국산 SCR 촉매의 개발을 위하여 국내에서 안료용으로 생산되는 TiO$_2$를 촉매의 담체로 이용, V$_2$O$_{5}$/TiO$_2$ 하니콤 촉매를 제조하여 촉매의 활성 및 특성을 연구 중에 있다(이정빈, 1999).(중략)

• 기계와재료
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• v.24 no.2
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• pp.6-17
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• 2012

최근 산업구조의 고도화에 따라 다양한 산업분야에서 화석연료 등의 에너지소모가 급증하면서 환경문제의 심각성이 대두되고 있다. 그중 질소산화물(NOx)은 산성비와 광화학 스모그의 원인이 되며 눈과 호흡기를 자극하고 식물을 고사시키는 등 주요 대기오염물질로 규제되고 있다. 이와 관련하여 국제해사기구(IMO)에서는 선박대기오염물질의 배출을 규제하는 규정을 만들었으며, 최근에는 배출규제를 강화하는 등 적극적인 규제활동을 벌이고 있다. 따라서 본 논문에서는 선박배기가스 질소산화물의 배출규제 현황과 배출 규제안에 대응하기 위해 본 연구원에서 연구개발 중인 배기가스 오염물질 저감장치의 선택적 촉매 환원(Selective Catalytic Reduction, SCR)시스템에 관하여 간략히 기술한다.

• 기계와재료
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• v.24 no.2
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• pp.18-26
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• 2012

지구 환경오염문제가 대두되면서 세계 각국에서는 환경오염을 최소화하려는 움직임이 활발히 이루어지고 있다. 국제해사기구(IMO)에서는 해양 대기오염의 상당량이 선박에서 배출되는 배기가스에 의한 것으로 판단하고 있으며, 이에 따라 선진국을 중심으로 선박관련 환경규제 및 선박 배기가스 배출기준을 점차적으로 강화해 가고 있고, 친환경 선박 및 기자재 개발을 적극적으로 진행하고 있다. 현재 선박에 적용 가능한 NOx 제거장치로는 ECR(Exhaust Gas Recirculation), SCR(Selective, Catalytic Reduction), SAM(Scavenge Air Moistening) 등이 개발되었으며, 연소온도 조절 및 촉매 환원반응 등을 이용하여 NOx를 제거하고 있다. 현재 개발된 탈질설비 중 현실적으로 가장 적합한 것은 SCR시스템으로 인식되고 있으나, 연료효율 감소로 인하여 가스연료를 이용하거나 새로운 연료개발 등 사용연료에 변화를 주는 방법들이 미래의 대안으로 제시되고 있다.

• Transactions on Electrical and Electronic Materials
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• v.6 no.5
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• pp.214-220
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• 2005

The ferroelectric properties of the $Pt/PZT(Pb(Zr,Ti)O_3)/Pt$ capacitors are severely degraded when they are annealed in hydrogen-containing environment. Hydrogen atoms created by the catalytic reaction of Pt top electrode during annealing in hydrogen ambient penetrate into PZT films and generate oxygen vacancies by the reduction of the PZT films, which is likely to cause the degradation. The degree of hydrogen-induced degradation and the direction of voltage shift in P-E curves of the pre-poled PZT capacitors after annealing in hydrogen ambient is dependent on the polarity of the pre-poling voltage. This implies that oxygen vacancies causing hydrogen induced degradation are generated by hydrogen ions having a polarity. The degraded ferroelectricity of the PZT capacitors can be effectively recovered by the shift of oxygen vacancies toward the Pt top electrode interface during post-annealing in oxygen environment with applying negative unipolar stressing.

• Journal of ILASS-Korea
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• v.18 no.4
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• pp.196-201
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• 2013

SCR(Selective Catalytic Reduction) is a major after-treatment solution to reduce NOx emission in recent diesel engines. In this study, a metal foam is applied as an alternative SCR substrate and tested in a commercial diesel engine to compared with a conventional ceramic SCR system. Basic engine test from ND-13 mode shows that a metal foam catalyst has lower NOx conversion efficiency than a ceramic catalyst especially over $350^{\circ}C$. A metal foam catalyst has characteristics of high exhaust gas pressure before a SCR catalyst and high heat transfer rate due to its material and structure. NOx conversion efficiency of a metal foam catalyst shows an increasing tendency along with the increase of exhaust gas temperature by $500^{\circ}C$. The effect of urea injection quantity variation is also remarkable only at high exhaust gas temperature.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.6
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• pp.545-551
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• 2008

Fe/$Al_2O_3$ composite granules were prepared by combining sol-gel/oil drop method. The shape of granules were mainly determined by composition and concentration of aluminum precursor. The composite granule with the lowest aluminum concentration was synthesized with 0.75M boehmite solution. The prepared granules were tested as a catalyst in the plug-flow reactor for Fischer-Tropsch synthesis. Before the reaction, catalysts were activated by hydrogen reduction and synthesis gas treatment. The activation conditions and aluminum concentration have affected catalytic performance significantly.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.368-375
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• 2010

To alleviate NOx emission, a variety of approaches has been applied. In marine diesels, the application of SCR systems has been considered an effective exhaust aftertreatment method for NOx emission control. Most current SCR systems use a various catalyst for the reaction of ammonia with NOx to form nitrogen and water. In theory, it is possible to achieve 100% NOx if the NH3-to-NOx ratio is 1:1. However, the reaction has a limited non-uniformity of the exhaust gas flow and ammonia concentration distribution. Therefore it is necessary to investigate the optimum flow conditions. In order to achieve uniform flow at monolith front face, we are equipped with a various mixed device. In this paper, it is presented that the mixed devices play an important role improvement of flow patterns and particle distributions of NH3 by numerical simulation.

• Journal of computational fluids engineering
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• v.15 no.4
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• pp.9-16
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• 2010

To alleviate NOx emission, a variety of approaches has been applied. In marine diesels, the application of SCR systems has been considered an effective exhaust aftertreatment method for NOx emission control. Most current SCR systems use a various catalyst for the reaction of ammonia with NOx to form nitrogen and water. In theory, it is possible to achieve 100% NOx if the $NH_3$-to-NOx ratio is 1:1. However, the reaction has a limited non-uniformity of the exhaust gas flow and ammonia concentration distribution. Therefore, it is necessary to investigate the optimum flow conditions. In order to achieve uniform flow at monolith front face, we are equipped with a various mixed devices. In this paper, it is presented that the mixed devices play an important role improvement of flow patterns and particle distributions of $NH_3$ by numerical simulation.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.23-24
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• 2006

The International Maritime Organization announced that the regulation of nitrogen oxide put into force for vessels constructed after 2000 from May, 2005 as agenda is satisfied on May, 2004. A honeycomb-typed Pillared Inter-Layered Clay(PILC) catalyst was developed for do-NOx SCR system in 2004. This catalyst has been applied to 9H25/33 engine that is one of the main diesel engines in Engine Machinery Division of the Hyundai Heavy Industries CO., LTD. In addition, we have tried to develop better catalysts in the aspects of easy synthetic method and performance.

• Journal of Power System Engineering
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• v.17 no.1
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• pp.19-26
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• 2013

The purpose of the study is carried out volume optimization of a combined system consisting of an LNT and SCR catalysts from the standpoint of its economic feasibility and de-NOx performance. Under the rich air-fuel ratio conditions for 5s (${\Phi}$=1.1), CO, $H_2$ and THC were generated at levels of 4%, 1.2% and $110ppmC_1$, respectively. The NOx conversion of the 1+1 combination was 5% lower than that of the 1.5+0.5 combination, however the reduced volume of the LNT catalyst decreased the total cost by about 6%. Therefore, the optimal volume ratio of the LNT and SCR catalysts was found to be the 1+1 catalyst combination, which has the highest total score in the terms of an economic feasibility and the NOx performance.