Analysis of the Influence of Fuel Sulphur Content on Diesel Engine Particulate Emissions

The motor vehicle is one of the main sources of pollutant emissions, especially in urban areas. Environmentally friendly fuels are regarded as very effective means to decrease emissions.

With regard to diesel engines, the reduction in nitrogen oxides and particulates are major problem areas. Although the fuel influence on NO_x is comparatively low, the composition and parameters of diesel fuel have a big influence on particulate emissions and composition. Sulphur content is one of fuel proprieties, which has the most considerable influence on particulates.

This paper describes results of the research on particulate emissions from diesel engines fuelled with research fuels of differing sulphur content. The sulphur content of the research fuels varied from 2000 ppm through 350 ppm (EURO III) and 50 ppm (EURO IV limit, which will be in force in the European Community from 1 January 2005) up to less than 5 ppm. The experiment was undertaken on a passenger car with an high-speed, four-cylinder turbocharged, diesel engine with swept volume of about 2 dm³ and a similar engine installed on a engine test bench. The experiments confirmed the significant influence of sulphur content in diesel fuel on particulate emissions. Therefore, the sulphur content in diesel fuels should be reduced further.