In order to fulfill future emission limits for heavy-duty vehicles like Euro 4, Euro 5 and US'07/'10 measures on the exhaust gas are required. The selective catalyst reduction system (SCR system) with urea as reducing agent is a promising approach for reduction of NOx emissions. Along with that the fuel consumption can be reduced by upto 5 % - 7 % compared to alternative measures of NOx reduction. This takes into account environmental aspects like C02-emission as well as economical aspects. The DENOXTRONIC system provides the reducing agent urea water solution, also called AdBlue, according to the raw emission of the engine. The properties and the behavior of the catalyst are taken into account by mathematical models. Engine tests based on the European transient cycle show with first prototypes of catalysts a NOx conversion rate of approximately 60 % with an average ammonia slip of 2 ppm. Using a dynamic model for the dosing strategy the NH3 slip can be reduced to an average value of approximately 1 ppm compared to the stationary model. With modern catalysts a NOx conversion rate of 80 % is achievable without the usage of an exhaust gas sensor. Thus an SCR-catalyst system with urea as reducing agent provides an important contribution for achieving future emission limits. Due to the market demand Bosch is developing the DENOXTRONIC system. It is currently in the field test phase in different trucks. Start of serial of production will be in 2004.
Control strategy for No(x) - emission reduction with SCR
2003
5 Seiten, 8 Bilder, 8 Quellen
Aufsatz (Konferenz)
Englisch
Control Strategy for NOx - Emission Reduction with SCR
SAE Technical Papers | 2003
|Control Strategy for NOx -Emission Reduction with SCR
British Library Conference Proceedings | 2003
|Control strategy for NOx-emission reduction with SCR
Kraftfahrwesen | 2003
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