The challenges of an aftertreatment system for Stage V with SCR-F

The introduction of the Stage V emission legislation requires a Particulate Matter (PM) filtration due to the Particle Number (PN) limit.The main objective of FPT’s Stage V development was to maintain the proven benefits of the high efficiency SCR-only technology implemented for Stage IV (HI-eSCR). In particular this involved low fuel consumption, compact and maintenance-free design as well as an overall robust layout.FPT integrated the filter function on the SCR (SCR-F) in cooperation with catalyst and substrate suppliers to meet all these challenging objectives. During the development further challenges as the reduction of SCR performance due to ash loading as well as the soot regeneration had to be tackled.FPT’s HI-eSCR2 for Stage V reaches all emissions targets while maintaining the muffler volumes and canning designs of Stage IV.A description of the HI-eSCR2 concept for Stage V as well as the development challenges are described in this paper.