COMPRESSION IGNITION ENGINE SYSTEM WITH IMPROVED REGENERATION VIA CONTROLLED ASH DEPOSITS

摘要

An engine system includes an electronically controlled compression ignition engine configured to burn diesel fuel and a high ash oil to produce an exhaust with a temperature and NOx to soot ratio as well as a controlled level of ash deposits on the particulate filter of the system. An aftertreatment system is fluidly connected to the engine and includes a diesel oxidation catalyst, a reductant supply, and a diesel particulate filter coated with a NOx reduction catalyst. The soot load density on the diesel particulate filter can be stabilized by oxidizing soot at about a same rate as the compression ignition engine is supplying soot to the aftertreatment system.

主权项

1. A method of operating an engine system comprising:
burning a high ash oil in a compression ignition engine, during a break-in period, to generate an ash deposit on a diesel particulate filter of an aftertreatment system fluidly connected to the compression ignition engine; burning a diesel fuel and a low ash oil in the compression ignition engine, after the break-in period, to produce exhaust with a temperature and a NOx to soot ratio, wherein a soot load is disposed on at least a portion of the ash deposit; catalyzing a NOx reduction reaction with a NOx reduction catalyst coated on the diesel particulate filter; and stabilizing the soot load on at least the portion of the ash deposit by oxidizing soot at about a same rate as the compression ignition engine is supplying soot to the aftertreatment system.