Patent ID: 8713914
Filing Date: 2014-05-06
Classification: F01N,F02D,Y02T

Abstract:
1. Method for monitoring a hydrocarbon-selective catalytic reactor device of an exhaust aftertreatment system of an internal combustion engine operating lean of stoichiometry, comprising: monitoring an intake mass airflow and determining an associated exhaust mass airflow; determining a temperature differential across only a forward portion of the hydrocarbon-selective catalytic reactor device; determining a monitored space velocity associated with the exhaust mass airflow across only the forward portion of the hydrocarbon-selective catalytic reactor device; injecting a reductant into an exhaust gas feedstream upstream of the hydrocarbon-selective catalytic reactor device including commanding a mass flowrate of the reductant that achieves a stoichiometric NOx concentration/reductant ratio in relation to the NOx concentration in the exhaust gas feedstream; determining a measure of deactivation of the forward portion of the hydrocarbon-selective catalytic reactor device corresponding to the temperature differential across only the forward portion of the hydrocarbon-selective catalytic reactor device and the monitored space velocity during said injecting the reductant; and controlling operation of the engine based upon the measure of deactivation of the forward portion of the hydrocarbon-selective catalytic reactor device.