Internal combustion engine with exhaust-gas aftertreatment arrangement and intake air arrangement and method for operating an internal combustion engine of said type

摘要

A system and method for controlling temperature of a urea reductant to form ammonia for NOx reduction in a selective catalytic reducer coupled to a turbocharged engine exhaust by portioning a flow across the reductant of one or more of the following: a combination of compressed air and ambient air; and/or a combination of the exhaust upstream and downstream the turbine.

主权项

1. An internal combustion engine comprising:
an intake system for the supply of charge air; an exhaust-gas discharge system for the discharge of exhaust gases; at least one selective catalytic converter arranged in the exhaust-gas discharge system for the reduction of nitrogen oxides; an oxidation catalytic converter being arranged, as a further exhaust-gas aftertreatment system, in the exhaust-gas discharge system upstream of the at least one selective catalytic converter; wherein a bypass line branches off from the intake system and issues air into the exhaust-gas discharge system between the oxidation catalytic converter and the at least one selective catalytic converter; and a dosing device within the bypass line and being provided for introducing liquid urea as a reducing agent for the at least one selective catalytic converter into the bypass line.