Journal Article
On-Engine Investigation of SCR on Filters (SCRoF) for HDD Passive Applications
2013-04-08
2013-01-1066
A 4-way Heavy-Duty Diesel (HDD) emissions control aftertreatment system typically consists of diesel oxidation catalyst (DOC), catalyzed soot filter (CSF), urea-based selective catalytic NOx reduction (SCR) and NH₃ slip control catalyst (AMOX). Incorporating the SCR functionality into the soot filter (SCRoF) has great potential to reduce system costs and package volume/weight. In this paper, we discuss some of the recent Cu-Zeolite-based SCR on filter (SCRoF) developments targeting Passive filter regeneration applications. The on-engine investigation of complete DOC+SCRoF+AMOX system focused on three major areas: 1) SCR performance of NOx conversion efficiency and NH₃ slip under both steady state and transient testing conditions; 2) SCRoF system response to sulfur exposure and subsequent sulfur removal for activity recovery; and 3) Characteristics of filter soot load, pressure drop, and passive soot oxidation in SCRoF.
