Self Regenerating Catalyzed Diesel Aftertreatment System

Even though the use of ceramic traps has lost popularity during the last few years, mainly due to the severe problems encountred during thermal regeneration, advances in the design of combustion chambers, improvement of fuels and lubricants, higher injection pressures, etc., have made possible to re-think the concept of mechanical filtration of Diesel¹ particulate matter (DPM).

In this paper a system is presented to automatically filter DPM and regenerate the ceramic filters under less stringent conditions. The use of a catalytic layer permits to lower the soot (DPM) activation energy to some easier to handle temperature levels. A system is then proposed as a retro-fit for new and used engines with the aim to target mainly the large metropolitan areas, where passenger buses are used extensively.