Abstract
Regulated and unregulated emission components were measured for five Urea SCR vehicles under commercial using. One of them emitted high rate of NOx, PM and NH3. A major reason of this deterioration would be HC poisoning, as NOx and NH3 increased drastically in the case of other vehicles tested after long time idling, and as over 20 minutes of high load operating could recover the NOx emission performance. Global warming effect including N2O were also investigated. From results, N2O emission from urea SCR vehicles was quite high and total amount of global warming effect of Urea SCR vehicle was 20 % or more worse than it of an old vehicle of same sized without after treatment devices.
