Method and device for aftertreatment of exhaust gases of internal combustion engines

Abstract

The invention relates to a method for exhaust gas aftertreatment of an internal combustion engine, in particular for regenerating a particle filter in the exhaust gas duct of the internal combustion engine, wherein the particle filter is loaded with soot particles during normal operation of the internal combustion engine. In order to reach the regeneration temperature of the particulate filter, the internal combustion engine is operated with a fuel-rich mixture and at the same time secondary air is introduced into the exhaust gas duct, wherein the unburned fuel components are converted exothermicly on the particulate filter with the secondary air until the particulate The filter is heated up to regeneration temperature. If the regeneration temperature is reached, the internal combustion engine is operated with a stoichiometric combustion air ratio and secondary air for oxidizing the soot particles trapped in the particle filter is blown into the exhaust gas channel, wherein the secondary air quantity is adjusted by λ The probing takes place downstream of the point of introduction for the secondary air and upstream of the particle filter.

Description

technical field [0001] The invention relates to a method and a device for aftertreatment of exhaust gases of internal combustion engines. Background technique [0002] The continuous tightening of exhaust gas emission regulations places high demands on vehicle manufacturers, which are met by corresponding measures for reducing the original engine emissions and by corresponding exhaust gas aftertreatment devices. With the introduction of the next legal phase EU6, limit values ​​for the number of particulates are also prescribed for gasoline engines. What this can cause is that, in some models, it may be necessary to use a gasoline particulate filter. During driving operation, such gasoline particulate filters are loaded with soot. In order for the exhaust gas back pressure to not rise too strongly, the gasoline particulate filter must be regenerated continuously or periodically. In order to carry out the thermal oxidation of the soot trapped in the gasoline particulate fil...

AI Technical Summary

Problems solved by technology

Furthermore, expensive sensor devices are required to monitor and control regeneration

However, the disadvantage with this lean combustion control is that the regeneration temperature required for regeneration of the particulate filter is not reached just in low part load operation and during short trips

Furthermore, during the lean-burn regulation of the engine, nitrogen oxides cannot be sufficiently converted by the three-way catalytic converter because no reducing agent for nitrogen oxides is present

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