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Future Diesel emission standards for passenger cars, light and medium duty vehicles, require the combination of a more efficient NOx reduction performance, a significant reduction of fuel consumption along with the opportunity to reduce the complexity and the package requirements to facilitate it. Recent activities on catalytic products allows for the SCR active compounds to move from the ceramic substrate located in the underbody to the DPF substrate already located in a close coupled position to achieve the benefit of the highest temperature. This newly developed SCR-coated DPF has massively improved the potential of NOX reduction. As published in the SAE-2014-0132 “advanced compact mixer: BlueBox” [1] it is crucial to inject Adblue®/DEF with a very high mixing performance level.

Future Diesel emission standards for passenger cars, light and medium duty vehicles, require the combination of a more efficient NOx reduction performance along with the opportunity to reduce the complexity and the package requirements to facilitate it. With the increasing availability of aqueous urea, DEF or AdBlue® at service stations, and improved package opportunities, the urea SCR technical solution has been demonstrated to be very efficient for NOx reduction; however the complexity in injecting and distributing the reductant remains a challenge to the industry. The traditional exhaust system contains Diesel Oxidation Catalysts (DOC), Diesel Particulate Filters (DPF) and Selective Catalytic Reduction (SCR), all require additional heat to facilitate each of their specific functions.

The use of a diesel particulate filter (DPF) is one of the most flexible methods of reducing particulate emissions from diesel engines, and has the advantage of controlling both the number and mass of particulate emissions. To maintain engine performance over time, the soot accumulated in the filter needs to be removed by oxidation. This paper describes the development of a novel iron based fuel-borne additive that controls soot deposit build-up in DPFs. This technology controls soot accumulation at significantly lower treat rates than those of previously reported [1] additives at temperatures well below those previously required for soot combustion. Ash accumulation testing and the chemical characterisation of the ash are also described. Any successful solution to the problem of soot accumulation in the filter needs to be harm free in the field.

In the past twenty years, several works has been done on Diesel Particulate Filters (DPF), but the main obstacle for a car application was the regeneration in all operating conditions of the filter by combustion of particles that have been retained in the filter. The goal of this study was to address this main concern by developing a new system. The tests were performed on the most difficult test conditions: urban cycles only that mean low temperature. After screening of various regeneration solutions, electrical regeneration has been chosen but first test performed on cordierite filters showed some failures due to lack of thermal resistance of cordierite filter in some very severe conditions The second part of the experiment was done on an improved system consisting of electrical regeneration, silicon carbide filter, more accurate pressure sensors, and lower content of additives. These tests on urban cycle showed good control for process regeneration.