METHOD OF DEPLETING NITROUS OXIDE IN EXHAUST GAS AFTER-TREATMENT FOR LEAN-BURN ENGINES

摘要

The present invention relates to a method for exhaust gas after-treatment for essentially lean-burn internal combustion engines and also a corresponding advantageous exhaust gas after-treatment system. In particular, the present invention relates to reducing the proportion of the greenhouse gas N20 in the total exhaust gas from a corresponding internal combustion system using at least one NOx storage catalyst as exhaust gas purification element. The objective of the invention is to operate the N20 depletion catalyst located downstream of the NOx storage catalyst under lambda=<1 conditions when the N20 formed by the NOx storage catalyst reaches the N20 depletion catalyst.