Approach to Air Quality Improvement: Necessity of Improving Fuel Quality for Clean Emission Vehicles

摘要

A lot of vehicle technologies have been developed to improve air quality of urban area, fuel economy and decreasing CO_2. Improvement of combustion and catalyst efficiency (catalyst itself and catalyst utilizing techniques ( quick activation, accurate air fuel ratio control)) lead gasoline engines to satisfy strict California PZEV standard. On the other hand, decrease of NOx and PM of diesel engines was difficult because there was not an effective emission control technology. However, the new technique, which can decreases NOx and PM simultaneously has been developed recently. This state-of-the-art technique including accurate fuel injection control by common rail system enables to accomplish Euro4 emission regulation for diesel engines. However, because fuel quality has large influence on those technologies, it is essential to improve fuel quality in the market to improve air quality. Especially, decreasing sulfur and keeping cleanliness of fuel injectors and intake valves to enable accurate fuel injection control are important.