Cummins Inc.
CROSSFLOW PNA-SCR AFTERTREATMENT DEVICE

Abstract:

An exhaust aftertreatment system includes a cross-flow selective catalytic reduction catalyst. The cross-flow selective catalytic reduction catalyst includes a housing and a substrate assembly. The substrate assembly includes a plurality of first substrate layers defining a plurality of first flow channels and a plurality of second substrate layers defining a plurality of second flow channels. The exhaust aftertreatment system includes a passive NO.sub.x adsorber. The passive NO.sub.x adsorber includes a housing. The housing includes an inlet in exhaust gas receiving communication with the plurality of first flow channels of the cross-flow selective catalytic reduction catalyst. The housing includes an outlet in exhaust gas providing communication with the plurality of second flow channels of the cross-flow selective catalytic reduction catalyst. The passive NO.sub.x adsorber includes a substrate positioned in the housing. The substrate includes a passive NO.sub.x adsorber washcoat.