Exhaust gas apparatus and method for purifying exhaust gas in internal combustion engine

摘要

A diesel particulate filter 14 that traps particulate matters in an exhaust gas and a NOx trap catalyst 13 that traps NOx in the exhaust gas are disposed in an exhaust passage ( 10 ) in an internal combustion engine ( 1 ). When a regeneration timing of the diesel particulate filter ( 14 ) and one of a regeneration timing of SOx and a regeneration timing of NOx are overlapped, the diesel particulate filter regeneration is carried out first and thereafter, the SOx regeneration or the NOx regeneration is carried out.