With focus on reducing the Green House Gases emissions, the use of biodiesel as an alternative fuel, in special for buses that runs on the Brazilian metropolitan areas has been even higher. Additionally, with the introduction of the new legislation for diesel engines in 2012, CONAMA PROCONVE P7, that in order to attempt to its requirements uses different kinds of exhaust gases after treatment systems, the necessity of knowing the behavior of those “P7 engines” operating with different biodiesel contents on blends with regular fossil fuel or even pure biodiesel has been an important issue to ensure the benefits of using such alternative fuel.
On this evaluation, blends of 5%, 10%, 20%, 30%, 50%, 75% and 100% of biodiesel content in ANP65/2011 A_S50 Diesel Fuel (50ppm Sulfur content) was experimented in a Mercedes-Benz OM926LA E5 engine with SCR (Selective Catalyst Reaction) exhaust gases after treatment system. This paper presents the tests performed in engines test benches (dynamometers) equipped with all required measurement devices that are able to measure not only its performance in terms of power, torque specific fuel consumption and fuel injection pressure, but also to evaluate the influence of biodiesel on the engine gaseous emissions.
With the obtained tests results it's possible to evaluate what biodiesel content in fossil diesel blends presents better benefits balance in terms of Nitrogen Oxides increase (NOx), Particulate Matter reduction (PM), mechanical stress over the engine and its exhaust gaseous after treatment system, still presenting a lower impact over the metropolitan areas air quality.