Impact of methanol and CNG fuels on motor-vehicle toxic emissions

Technical Report · Tue Jan 01 04:00:00 EST 1991

OSTI ID:6059273

Black, F; Gabele, P

The 1990 Clean Air Act Amendments require that the Environmental Protection Agency investigate the need for reduction of motor vehicle toxic emissions such as formaldehyde, acetaldehyde, benzene, 1,3-butadiene, and polycyclic organic matter. Toxic organic emissions can be reduced by utilizing the control technologies employed for regulated THC (NMHC) and CO emissions, and by changing fuel composition. The paper examines emissions associated with the use of methanol and compressed natural gas fuels. Both tailpipe and evaporative emissions are examined at varied ambient temperatures ranging from 20 C to 105 F. Tailpipe emissions are also examined over a variety of driving cycles with average speeds ranging from 7 to 48 mph. Results suggest that an equivalent ambient temperatures and average speeds, motor vehicle toxic emissions are generally reduced with methanol and compressed natural gas fuels relative to those with gasoline, except for formaldehyde emissions, which may be elevated. As with gasoline, tailpipe toxic emissions with methanol and compressed natural gas fuels generally increase when ambient temperature or average speed decreases (the sensitivity to these variables is greater with methanol than with compressed natural gas). Evaporative emissions generally increase when fuel volatility or ambient temperature increases (however, the relative contribution of evaporative sources to the aggregate toxic compound emissions is small).

• Research Organization: Environmental Protection Agency, Research Triangle Park, NC (United States). Atmospheric Research and Exposure Assessment Lab.
• OSTI ID: 6059273
• Report Number(s): PB-92-110378/XAB
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
030800 -- Natural Gas-- Environmental Aspects
10 SYNTHETIC FUELS
100900 -- Synthetic Fuels-- Environmental Aspects-- (1990-)
54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
ALCOHOL FUELS
AMBIENT TEMPERATURE
AUTOMOTIVE FUELS
CHEMICAL COMPOSITION
COMBUSTION PRODUCTS
COMPRESSED GASES
ENERGY SOURCES
ENVIRONMENTAL IMPACTS
EXHAUST GASES
FLUIDS
FOSSIL FUELS
FUEL GAS
FUEL SUBSTITUTION
FUELS
GAS FUELS
GASEOUS WASTES
GASES
MATTER
METHANOL FUELS
NATURAL GAS
SYNTHETIC FUELS
TOXICITY
VELOCITY
VOLATILE MATTER
WASTES