Summary: | 碩士 === 國立成功大學 === 環境工程學系 === 87 === This research investigates the profiles of airborne volatile organic compounds (VOCs) in southern Taiwan, where is one of the regions suffered with serious ozone pollution. Field measurements were conducted to take sample air with canisters and analyzed for 55 VOCs species included anthorogenic and biogenic sources. Field measurements were implemented at EPA air quality monitoring stations located at Taliao, Chaochow, Sanming and Hsoukang.
At Taliao, Chaochow, Sanming and Hsoukang station, the average concentrations of total VOCs were 103.7, 194.7, 339.7, 273.4 mg/m3, respectively, at hours 06:00~09:00 (LCT). The values of mass fraction for paraffin, oleffin and aromatic VOCs at four stations were 28~47%、7~12%、41~52%, respectively. Toluene is the highest concentration species among the aromatic VOCs with a average concentrations of 55 mg/m3。
Receptor model (CMB) was also applied to estimate the sources contribution. The results indicate that 47~68% of airborne VOCs came from vehicle exhaust. However, vehicle emission contribute 20~34% of the reactivity of airborne VOCs.
There were no clear relationship between the daily maximum ozone concentrations and NMHC/NOx ratios in southern Taiwan. The range of NMHC/NOx ratios were in the range of 5~15 and with a average of 10.2. It means the control scenario of ozone is both NOx and NMOC emissions reduction effective by Photochemical model simulate shows that the minimum requirement of VOCs reduction is 15~20% and is 10% for NOx control.
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