Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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A Study on the Injection Characteristics of Urea Solution to Improve deNOx Performance of Urea-SCR Catalyst in a Heavy Duty Diesel Engine

대형 디젤 엔진용 요소분사 SCR촉매의 deNOx 성능향상을 위한 요소수용액의 분사특성 연구

  • Jeong, Soo-Jin (Advanced Power & IT Research Center, Korea Automotive Technology Institute) ;
  • Lee, Chun-Hwan (Environmental Parts R & D Center, Korea Automotive Technology Institute)
  • 정수진 (자동차부품연구원 첨단동력/IT 종합연구센터) ;
  • 이천환 (자동차부품연구원 환경부품연구센터)
  • Published : 2008.07.01
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Abstract

Urea-SCR, the selective catalytic reduction using urea as reducing agent, has been investigated for about 10 years in detail and today is a well established technique for deNOx of stationary diesel engines. In the case of the SCR-catalyst a non-uniform velocity and $NH_3$ profile will cause an inhomogeneous conversion of the reducing agent $NH_3$, resulting in a local breakthrough of $NH_3$ or increasing NOx emissions. Therefore, this work investigates the effect of flow and $NH_3$ non-uniformities on the deNOx performance and $NH_3$ slip in a Urea-SCR exhaust system. From the results of this study, it is found that flow and $NH_3$ distribution within SCR monolith is strongly related with deNOx performance of SCR catalyst. It is also found that multi-hole injector shows better $NH_3$ uniformity at the face of SCR monolith face than one hole injector.

Keywords

References

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