Combinations of Technical Measures for Reduction of Particle Emissions Toxicity of 2-S Scooters

摘要

2- and 3-wheelers with 2-S propulsion are still a very serious source of air pollution worldwide in many urban areas. Therefore, every effort to reduce the emissions of those vehicles is an important contribution to improve the air quality.In the present work detailed investigations of regulated emissions and of particle emissions of 2-stroke scooters with direct injection and with carburator were performed.To demonstrate the emission reduction potentials some possibilities of emission improvements were grouped into steps. These technical measures were:rn1. Higher tier lube oilsrn2. Lower oil dosingrn3. Active oxidation catalystrn4. Supplementary filtration & oxidation devise (WFC)rn5. Special fuel.Particle mass and nanoparticles (number), which are amply present in 2-stroke exhaust gas and which contribute strongly to the toxicity level are still unlimited by the international exhaust gas legislation. They were extensively investigated in the present project series.The Toxicity Equivalence (TEQ) of the emitted particle mass was evaluated by means of PAH analysis and comparison with the standards based on benzo[a]pyrene (EPA method).It was demonstrated, that a strong reduction of particle mass emissions and toxicity is possible by means of a combination of these technical measures.There are also further possibilities of improvements, like total filtration or use of alternative fuels.