International Journal of Automotive Technology

The Korean Society of Automotive Engineers (한국자동차공학회)
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STATIC CHARACTERISTICS OF A UREA-SCR SYSTEM FOR NOx REDUCTION IN DIESEL ENGINES

  • Nam, J.G. (Division of Marine Engineering, Mokpo National Maritime University)
  • Published : 2007.06.30
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Abstract

This paper presents the static characteristics of a urea-SCR system. The static characterization of the urea-SCR system was generated by sweeping urea flow rates at common engine torque/speed operating points. Several experiments were performed using engine operating points at different raw NOx emission levels, space velocities, and SCR catalyst temperatures. The recorded NOx emissions from the engine exhaust outlet and engine tailpipe are then compared. The urea-SCR static system results indicated that a $50{\sim}60%$ NOx conversion is achievable at most engine operating points using the stoichiometric $NH_3/NOx$ ratio, and a high 98% NOx conversion is possible by exceeding the stoichiometric $NH_3/NOx$ ratio. The effect of the pre-oxidation catalyst volume was also investigated and found to have a profound impact on experimental results, particularly the static NOx conversion.

Keywords

References

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