A Study on the emission factors of volatile organic compounds from automobiles of different fuel types in Tunnel
Kim, Taeyun
Dept. of Environmental Engineering
The Graduate School
Yonsei University
This study aimed to determine the emission factors ...
A Study on the emission factors of volatile organic compounds from automobiles of different fuel types in Tunnel
Kim, Taeyun
Dept. of Environmental Engineering
The Graduate School
Yonsei University
This study aimed to determine the emission factors of volatile organic compounds (VOCs) based on different types of vehicles inside a tunnel. Many studies have been conducted on determining emission factors of vehicles in tunnels to calculate emission factors under real driving conditions. Pollutants inside a tunnel are influenced solely by the emissions from vehicles passing through it, excluding external pollution and photochemical reactions. Particularly, the advantage of tunnel study is that various types of vehicles are mixed is present under actual driving conditions, thus ca be taken into consideration in a comprehensive manner.
In this study, 56 types of morning precursor substances, which are measurement items of the Photochemical Assessment Monitoring Stations (PAMS) established by the US EPA, were analyzed using the canister method and Tenax tubes with GC-MS. For vehicle types, diesel high-emission vehicles, diesel low-emission vehicles, gasoline vehicles, LPG vehicles, electric vehicles, LPG, hybrid vehicles, and motorcycles were classified to calculate the emission factors. The concentration of captured carbon monoxide (CO) was measured in the range of 0 to 200 ppm using a carbon monoxide analyzer (EC9890T, Ecotech). In cases where the number of vehicles passing through exceeded 1,200 per hour, a decrease in vehicle speed due to traffic congestion was observed. Furthermore, higher CO values were observed during periods of traffic congestion, and the CO concentration was twice as high as the data from the roadside monitoring network in the adjacent Jongno-gu area during the same period. A decrease in CO concentration was confirmed as the vehicle speed increased.
Regarding the classification of vehicle types and fuel types, real-time recorded video inside the tunnel was visually examined. In cases where visual judgment was not possible, vehicle classification was based on the vehicle registration statistics provided by the Seoul Government. The estimated emission factors of tunnel vehicles showed that Alkanes, Alkenes, and Aromatic compounds had the highest emission factors in that order. These results were similar to the vehicle emission factors estimatedin previous studies conducted in The Lepold II Tunnel and Fu-Gui Mountain Tunnel.