Methanol, Ethanol and Jet Fuel Emissions Comparison from a Small Gas Turbine

A 60 H.P. gas turbine engine has been easily converted to operate on methanol and ethanol fuels. No unusual fuel system hardware problems were experienced during 15 hours of testing with methanol and one hour of testing with ethanol.

Our computer model's predicted low emissions of NOx and CO for methanol were closely approximated after the installation of an air atomizing fuel nozzle. Substantial NOx reductions also resulted from ethanol fuel. Hydrocarbon unburned fuel emissions were increased with methanol and ethanol.

Agreement is found with five previously reported methanol gas turbine experiments which indicate from 60% to 80% NOx reductions in comparison with distillate-type fuels. Combustor inlet temperature variation is considered as one cause of variability of reported CO emissions with methanol. Droplet size effects and increased ignition delay are considered to adversely affect methanol's CO and hydrocarbon emissions. Detailed emissions data for NOx, NO, NO₂ CO and hydrocarbons are reported for several series of fuel nozzle tests with methanol, ethanol and Jet A fuels.