LAUSR

Abstract To improve the synergy effects of post-processing equipment and decrease diesel engine emissions, the after-treatment synergy model is established to analyze the soot regeneration combustion of catalytic diesel particulate filter (CDPF) passive and active regeneration and downstream selective catalytic reduction (SCR) by NH3 (NH3–SCR) over Cu–ZSM–5. Kinetic models of nitric oxide oxidation on platinum-based catalyst, passive and active regeneration of CDPF and nitrogen oxide conversion in SCR are verified. Results show that the CDPF passive regeneration weakens the SCR performance with small inlet NO2/NOX ratio while enhances the SCR performance with large inlet NO2/NOX ratio, and active regeneration deteriorates SCR performance. Of all the factors, except temperature, the SCR NOX conversion varies with the NO2 concentration at the outlet of the CDPF during the CDPF passive regeneration, and the CDPF outlet oxygen concentration mainly affects downstream SCR performance under active regeneration conditions.