A study on reductants pulse supply to a NH₃-SCR catalyst toward NOx conversion improvement and reductants reduction (Second Report)

- Reduction of ammonia slip -

Abstract

In this study, the active control of reductant pulse supply was investigated using the SCR reaction model to improve the NOx purification ratio and reduce the amount of reductant supply in a urea-SCR catalyst system. The reduction of NH₃ slip was obtained when the active control of amplitude and frequency of NH₃ pulse supply was carried out at low temperature. Moreover, low NH₃/NOx ratio had roles in not only reducing extra NH₃ supply amount but also keeping high NOx conversion ratio by the improvement of NOx conversion by suppressing the formation of ammonium nitrate.