INVESTIGATION OF EMISSION RATES OF AMMONIA, NITROUS OXIDE AND OTHER EXHAUST COMPOUNDS FROM ALTERNATIVE-FUEL VEHICLES USING A CHASSIS DYNAMOMETER |
T. D. DURBIN, T. HUAI, S. H. RHEE, J. M. NORBECK |
University of California |
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ABSTRACT |
Exhaust emissions were characterized for a fleet of 10 alternative-fuel vehicles (AFVs) including 5 compressed natural gas (CNG) vehicles, 3 liquefied petroleum gas (LPG) vehicles and 2 85% methanol/15% California Phase 2 gasoline (M85) vehicles. In addition to the standard regulated emissions and detailed speciation of organic gas compounds, Fourier Transform Infrared Spectroscopy (FTIR) was used to measure ammonia (NH3) and nitrous oxide (N2O) emissions. NH3 emissions averaged 0.124 g/mi for the vehicle fleet with a range from <0.004 to 0.540 g/mi. N2O emissions aerated 0.022 g/mi over the vehicle fleet with range from <0.002 to 0.077 g/mi. Modal emissions showed that both NH3 and N2O emissions began during catalyst light-off and continued as the catalyst reached its operating temperature. N2O emissions primarily were formed during the initial stages of catalyst light-off. Detailed speciation measurements showed that the principal component of the fuel was also the primary organic gas species found in the exhaust. In particular, methane, propane and methanol composed on average 93%, 79%, and 75% of the organic gas emissions, respectively, for the CNG, LPG, and M85 vehicles. |
Key Words:
Alternative fuel vehicles (AFVs), Ammonia (NH3), Nitrous oxide (N2o), Fourier transform infrared spectroscopy (FTIR), Vehicle emissions |
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