Artigo Completo:

The use of biodiesel in Brazil was consolidated after 2005, when the Federal Government established a time frame to insert biodiesel in Brazilian energy matrix and so that a 5% biodiesel in diesel blend (B5) has been mandatory since January, 2010. Now the attention turns to blends with higher level of biodiesel and vehicle and engine assemblers, fleet owners and other private and governmental entities are conducting extensive researches on the subject. This paper evaluates the use of a 20% biodiesel in diesel blend (B20) in light duty vehicles with EURO III and EURO IV technologies and its impact on the durability of engines and systems. Vehicles of both technologies endured a field test during which they accumulated 100.000 km in urban and road circuits. They were then evaluated according to the deterioration of performance and pollutants emissions and wear of parts and components. Results were compared to those obtained in similar vehicles using a B5 blend as fuel, subjected to the same test conditions. Engine wear and deposit formation on rings, pistons and cylinders were evaluated by the manufacturers through visual and dimensional inspections, and were found compatible to the use of the engines; there was no significant differences between the groups. Track performance and chassis dynamometer emissions tests showed that EURO IV vehicles were less influenced by the use of differentiated fuels, with vehicles that run on B20 during the field test showing results statistically equivalent to those that run on B5. On the other hand, EURO III vehicles that run on B20 had performance losses up to 7% when compared to those that run on B5. They could not be evaluated according to their emissions.