Low-pressure EGR in Combination with Soot Filters For Diesel NOx and Particulate Control 2001-26-0006
Researchers worldwide are facing technical challenges regarding simultaneous reduction of diesel NOx and particulate matter. To address such challenges, several alternative approaches are being pursued by engine OEMs and catalyst companies with various levels of success. One of the approaches is the combined use of an EGR and a soot filter, where an EGR controls emissions of NOx, and a soot filter reduces particulate matter.
While most researchers focus their efforts on developing an EGR / soot filter system for new engines, the authors of this paper concern themselves with developing a system for retrofit applications. Such a system will have a significant impact on worldwide air quality and human health, as many existing engines can further be retrofitted. Once fully developed and proved to be efficient, this system could be adopted for OEM applications as well.
This paper discusses various practical aspects of implementing such a system, including engine performance and durability, passive and active EGR controls, soot filter performance with EGR and the suitability for specific applications. This paper is purely of an experimental nature, where most points are supported by experimental data, while a few others are given in the form of general discussion.
Contained in this paper are the results of extensive laboratory studies involving modern truck and bus engines. The proposed EGR / soot filter system demonstrated 35-42% reduction of NOx, and 85-88% reduction of TPM emissions.