• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2003년도 추계학술대회 논문집
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• pp.141-142
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• 2003

최근 자동차 수요증가 및 산업용 보일러 둥 급증하는 추세이며 이로 인한 대도시 대기오염 문제는 위험수위에 도달해 있다. 이러한 산업용 보일러, 화력발전소등 고정배출원과 자동차에서 발생하는 배기가스에는 인체에 유해한 일산화탄소(CO), 질소산화물(NOx), 황산화물(SOx)등이 다량 함유되어 있다. 유독성 가스중 질소산화물(NOx) 저감방법에는 특히 선택적 촉매환원법(Selective Catalytic Reduction, SCR)이 가장 널리 적용되고 있다. SCR법은 촉매하에서 NH$_3$, CO, 탄화수소(메탄, 에탄올, 프로판 등)의 환원제를 사용하여 NOx를 $N_2$로 전환하시키는 기술이다. (중략)

• 한국자동차공학회논문집
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• 제9권6호
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• pp.103-111
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• 2001

During cold-start period, the reduction of exhaust emissions is a challenging task. To decrease harmful gaseous substances such as HC, it is necessary to realize a fast catalyst warm-up. In this study, the performance of dual pipe exhaust system have been carried out through different test mode. From measurement of gas temperature and HC concentration, the following conclusions were derived ; 1) Compared with single pipe, dual pipe exhaust system remarkably increase temperature of exhaust gas going through M.C.C(Main Catalytic Converter). 2) W.C.C.(Warm-up Catalytic Converter) also decreases HC emission. To reduce HC emission, it is helpful to use W.C.C. as well as dual pipe exhaust system. 3) Using finite element method, it is shown that inner parts have much higher distribution of temperature than outer parts.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.61-63
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• 2015

In the low pressure selective catalytic reduction (LP SCR) system, the uniformity of both ammonia concentration and exhaust gas flow at the SCR catalyst layer are important design factor for the efficient SCR-deNOx performance. According to the shape of the guide vane and static mixer, numerical simulations were conducted to analyze flow patterns and finally to find out the appropriate alternative for uniform flow at the front of catalyst in the real scale LP SCR reactor. The variations of gas velocity and ammonia concentration were quantitatively evaluated. Based on the present results, the shape was devised to satisfy the design criteria.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.307-313
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• 2019

In order to design efficient Urea Decomposition Chamber (UDC) for the Low Pressure (LP) Selective Catalytic Reduction (SCR) system, numerical simulations were conducted with respect to various design parameters. The design parameters examined in this simulation include the chamber diameter, inlet and outlet shape of chamber, and urea injection point. Reaction kinetics for the urea decomposition was proposed and validated with the experimental data in the range of $300{\sim}450^{\circ}C$. The effects of design parameters on the performance of UDC were evaluated by the calculated urea conversion and pressure drop. As a result, the local optimum design values were derived by the parametric study.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.448-460
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• 2018

Copper nanoparticle-doped and graphitic carbon nanofibers-covered porous carbon beads were used as an efficient catalyst for treating synthetic phenolic water by catalytic wet air oxidation (CWAO) in a packed bed reactor over 10-30 bar and $180-230^{\circ}C$, with air and water flowing co-currently. A mathematical model based on reaction kinetics assuming degradation in both heterogeneous and homogeneous phases was developed to predict reduction in chemical oxygen demand (COD) under a continuous operation with recycle. The catalyst and process also showed complete COD reduction (>99%) without leaching of Cu against a high COD (~120,000 mg/L) containing industrial wastewater.

• 한국대기환경학회지
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• 제5권1호
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• pp.79-87
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• 1989

In order to reduce the smoke emission from the in-service city bus, this study was evaluated the particulate reduction efficiency and regeneration ability of the catalitic trap oxidizer (CTO) on the city bus (D0846HM engine) equipped with it. Before the on-road CTO test, the laboratory test of CTO on engine test-bench was performed. Reduction efficiencies of smokes and particulates were 54 and 45%, and those of gaseous pollutants such as carbon monoxide (CO) and hydrocarbons (HC) were 90 and 60%. In order to evaluate the regeneration ability of the CTO by the catalytic oxidation of trapped particulate, field test was performed on the in-service road. The regeneration temperature was 350$^\circ$ which was same with the exhaust temperature of city bus.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2004년도 추계학술대회 논문집
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• pp.107-109
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• 2004

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 1999년도 춘계학술대회 논문집
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• pp.305-306
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• 1999

• 대한환경공학회지
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• 제27권5호
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• pp.513-518
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• 2005

망간 산화물 촉매, 망간-세륨 산화물 촉매에서 톨루엔의 촉매 산화에 대하여 조사 하였다. XRD, TGA, 톨루엔-TPR 분석을 통해 촉매의 특성을 조사하였다. 톨루엔 산화반응에 있어서 망간 18.2 wt.% 세륨 10.0 wt.%이 적절한 비율인 것으로 나타났다. 그리고 세리아가 망간 산화물에서의 활성을 증진 시키는 것으로 보여진다. XRD결과 $MnO_2$가 황성 자리인 것으로 추측된다. TGA 톨루엔-TPR결과 세리아가 격자 산소의 이동성, 활성자리의 적절한 상화 상태, 저온에서의 환원능력 및 활성자리의 재산화 능력을 증진시키는 것으로 사료된다.

• 한국자동차공학회논문집
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• 제18권5호
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• pp.85-90
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• 2010

As the environmental regulation of vehicle emission is strengthened, investigations for $NO_x$ and PM reduction strategies are popularly conducted. Two current available technologies for continuous $NO_x$ reduction onboard diesel vehicles are Selective Catalytic Reduction (SCR) using aqueous urea and lean $NO_x$ trap (LNT) catalysts. The experiments were conducted to investigate the $NO_x$ reduction performance of SCR system which can control the ratio of $NO/NO_2$, temperature and SV(space velocity), and the model gas was used which is similar to a diesel exhaust gas. The maximum reduction efficiency is indicated when the $NO:NO_2$ ratio is 1:1 and the SV is 30,000 $h^{-1}$ in $300^{\circ}C$. Generally, ammonia slip from SCR reactors are rooted to incomplete conversion of $NH_3$ over the SCR. In this research, slip was occurred in 6cases (except low SV and $NO:NO_2$ ratio is 1:1) after SCR. Among 6 case of slip occurrence, the maximum conversion efficiency is observed when SV is 60,000 $h^{-1}$ in $400^{\circ}C$.