Press Release
Mercedes Introduces First EU4 and Diesel Particulate Filter
Permissible filter effect without fuel additives
For Mercedes-Benz, service life, everyday practicality and fuel consumption were key criteria in the development of the particulate filter system. For this reason, a filter system that was dependent on additives was simply out of the question. Investigations show that, although such fuel additives improve the burn-off of particles that have accumulated in the filter, the ash remaining in the filter channels is not renewable and, after a high mileage, this ash can block the filter. As a result, the exhaust gas back-pressure increases and, consequently, so does the fuel consumption and, in turn, the C02 emissions, whilst the performance of the engine drops continuously.
With the Mercedes-Benz particulate filter system, it is possible to achieve high mileages without the need for additional service measures. The filter is regenerated by adjusting, in accordance with requirements, various engine-control functions, such as fuel injection, intake-air throttle, exhaust-gas recirculation and boost-pressure control. In this way, it is possible to increase the temperature of the exhaust gas and the particles accumulated in the filter are burned off. Test results show that, after a high mileage, the residual ash is up to 75 percent less than that produced by additive-dependent filter systems. Sulphur-free fuels and specially developed engine oils will mean that these diesel particulate filters have an even longer service life.
Focus on reducing all emissions and fuel consumption
Due to the new particulate filter and its new CDI engines already outstanding by virtue of such features as common-rail direct injection, four-valve technology, exhaust-gas recirculation and oxidation catalytic converters Mercedes-Benz has now succeeded in reducing particulate emissions by about 87 percent since 1995. From 2005, the EU 4 limits also stipulate a further 84-percent reduction in gaseous emissions.
According to Professor Jürgen Hubbert: �The simultaneous reduction in exhaust-gas emissions and in fuel consumption is one of our primary objectives. However, in order to exploit fully the great future potential, we need not only state-of-the-art engine technology, but also both clean fuels and innovative fuels, such as ‘Biotrol’, the fuel recently introduced by us for diesel engines; this is manufactured from renewable raw materials and is clean-burning.�
Experience gained with particulate filters put into practice since 1985
Since the 1980s, Mercedes engineers have been working on reducing particle emissions. In 1985, Mercedes-Benz was the first car manufacturer in the world to fit diesel saloons destined for the US State of California with particulate filter systems. The experience gained during the course of this programme formed an important basis for the development of the innovative filter technology that will be available from October 2003.
