Exhaust gas purification system and exhaust gas purification method

摘要

An exhaust gas purification system with a diesel particulate filter in an exhaust passage of an internal combustion engine. A surface filtration cake layer formation enhancement control or a particulate matter generation amount reduction control is temporarily performed immediately after a forced regeneration treatment on the diesel particulate filter. The system and a method are directed to a particulate matter slip-through phenomenon in which the particulate matter slip-through amount temporarily increases immediately after particulate matter re-combustion in a forced regeneration treatment on the diesel particulate filter. The diesel particulate filter is disposed in the exhaust passage of the internal combustion engine and reduces the total amount of particulate matter emitted to the atmosphere immediately after the particulate matter re-combustion in the forced regeneration treatment on the diesel particulate filter.

主权项

1. An exhaust gas purification system comprising:
a diesel particulate filter disposed in an exhaust passage of an internal combustion engine; and a controller configured to
determine a particulate amount generated in the internal combustion engine by comparing a preset particulate matter generation amount database with a detected engine operation state,determine a particulate matter slip amount passing through the diesel particulate filter by comparing the preset particulate matter generation amount database with a preset particulate matter trap efficiency database, recombust particulate matter using a forced regeneration treatment of the diesel particulate filter, and temporarily perform a surface filtration cake layer formation enhancement control or a particulate matter generation amount reduction control based on the determined particulate matter generation amount and the determined particulate matter slip-through amount, immediately after the particulate matter re-combustion using the forced regeneration treatment on the diesel particulate filter,
wherein, when both the determined particulate matter generation amount and the determined particulate matter slip-through amount are smaller than respective preset thresholds, the surface filtration cake layer formation enhancement control is performed.