| 摘要 |
The exhaust fume purification of lean-driven internal combustion engines, in particular Diesel engines, is problematic as regards nitrogen oxide removal, since the exhaust fume has a high oxygen content, in particular when the internal combustion engine is underloaded. Setting a rich exhaust fume mixture is only possible by strongly choking the air supply to the internal combustion engine, but this necessarily reduces comfort. The oxygen content at the intake (11) of an internal combustion engine (1) can be reduced by increasing the exhaust fume return rate through an exhaust fume return line (4) when the NOx accumulator (7) is regenerated, so that a rich exhaust fume mixture is achieved already at the usual or even only slightly increased amounts of injected fuel. Such a regeneration of the NOx accumulator (7) is particularly advantageous in the lower underload range of the internal combustion engine (1). |
