Patent ID: 8615983

Claim:
A method for operating an internal combustion engine configured to operate lean of stoichiometry, comprising: employing an exhaust gas recirculation system configured as a high-pressure loop system including a conduit fluidly connected to a downpipe of the engine upstream of a turbine section of a turbocharger to recirculate a portion of an exhaust gas feedstream of the engine, said exhaust gas recirculation system including an exhaust gas treatment device comprising: a particulate filter device fluidly coupled to a heat exchanger fluidly coupled to an intake system of the engine downstream of a compressor section of the turbocharger, the particulate filter device configured to filter particulate matter in the exhaust gas feedstream utilizing a filter substrate, and continuously regenerate the filter substrate utilizing an oxidation catalyst coated on the filter substrate, the oxidation catalyst enabling the particulate matter to continuously oxidize at lower exhaust gas feedstream temperatures; a hydrocarbon trap device fluidly coupled to the particulate filter device, the hydrocarbon trap configured to trap unburned hydrocarbons within the exhaust gas feedstream, and oxidize the unburned hydrocarbons utilizing a substrate coated on the hydrocarbon trap device; reducing temperature of the portion of the exhaust gas feedstream recirculated to the intake system of the engine; and reducing mass flowrate of particulate matter and hydrocarbons borne in the recirculated portion of the exhaust gas feedstream upstream of the heat exchanger to reduce deposition of particulate matter and hydrocarbons onto and adhesion to surface areas of the heat exchanger.