Field Measurements of Airport Emissions and Air Pollutants Including Aerosols
In summer 2005, autumn 2004, speciated VOC’s, NOx, CO, CO2, SO2, and other pollutant have been measured at Paris airports near runways and stands and at differnet locations. Airborne aerosol fine particles, have been measured [7nm to 10micro-m], in number and mass concentration, morphology and chemical content. Emission indices of commercial aircraft engines including APU have been measured at different power settings.
25m behind running engines, volatile particles (10 nm diameter) dominate the spectrum whereas the soot mode (60-80nm) has values lower by a factor of 100 for any engine power settings. The following VOC's have been mainly produced by engines: ethane, ethene, ethyne, propene, 1-3 butadiene,1-butene, benzene, i-butene and toluene.
Ultra-fine volatile particles are maximum beside stands,roads and engine test areas. Downwind measurements indicate importance of diffusion and coagulation to control aerosol behavior at airport. TEM analyses indicate ultra-fine and aggregated soot for diameter around 20nm to 60 nm. Chemical analysis of samples indicates the presence of S, Si, Fe, Ca, and K. and impaction of sulfate volatile compounds.
In summer, ozone depicts a maximum at 4 p.m. correlated to high temperature. Airport-O3 is lower, due to higher NOx than at vicinities and in Paris city. Speciated VOC’s and NO/NO2 show diurnal variations correlated to airport operations. HCHO and CH3CHO show higher concentration near stands, taxiways and engine test area. Take-off engine plumes indicate higher NOx concentration of NOx and PM number concentration. Background values near runways are low, transient variations are strongly dependent on change-over operations of runways.