- 學位論文
以自強隧道實驗研究台灣本土移動源粒徑分佈特徵及相關排放係數
Traffic emission factors of ultrafine particles in Taiwan - A tunnel study on particle size distributions
摘要
本研究於臺北市自強隧道進行超細懸浮微粒(Ultra-fine particles, UFP)之採樣分析，分析粒狀狀污染其粒徑分布，以實驗架構設計可區分成為固定點採樣分析、移動式推車採樣分析。本實驗以移動距離與交通時段作為操作變因分析多種污染物，包含一氧化碳、二氧化碳、超細懸浮微粒(PM1.0)、細懸浮微粒(PM2.5)，並結合簡易空氣品質量測儀量測隧道內不同距離下之各污染物濃度。本研究主要著重隧道交通產生之污染物排放特徵，量測微粒數目濃度和粒徑分佈，並紀錄環境溫、濕度變化，作為建立本土排放數據之依據。並進一步配合車流計數資料，以多元回歸方式求取各不同車種之排放係數。同時討論在行駛狀態下，車流排放係數在各距離下的增減變化之原因。 根據簡易空氣品質量測儀之粒徑分佈範圍，顯示0.3~0.5 µm的區間約占總微粒數目約90 %，而較大粒徑之0.5~1.0 µm、1.0~2.5 µm區間分別只占8 %、1 %，顯示大部分微粒都集中於小微粒部分。平日、假日各粒徑的數目比率，同時主要以不同時間段(7:00~9:00、11:00~13:00)作為區分，能發現各時段工作日及假日距離變化差異不明顯。雖粒徑大小與比率隨距離有所差異，但在整體不同時間上表現出大微粒變化較少，各時段平日及假日比率落在1~1.4之間，而隨粒徑越小其平日、假日的污染物濃度比率越高。由此比率顯示，交通源平日及假日的交通量差異造成的影響主要在小微粒的累積。 最後各車輛依其種類可區分為汽油車(Light-duty vehicles, LDVs) 、機車(Motorcycle, MC)及柴油車(Heavy-duty vehicles, HDVs)等種類。汽油車、機車、柴油車之超細懸浮微粒排放係數峰值分別出現於23.3 nm、25.9 nm、25.9 nm，其排放係數值分別為0.26±0.1、0.21±0.08、1.49±0.61 1015#/kg-fuel。由結果反應汽油車、機車行駛所造成的排放係數相當接近，而在柴油車之排放係數上，為汽油車輛5.7倍，為一大貢獻來源。因此即便柴油車輛組成佔比較低，依舊不可忽略柴油車輛所造成之污染影響。
並列摘要
In this study, ultra-fine particles (UFP) was measured in the Zi-Chang Tunnel in Taipei City. The particle size distribution of pollution was analyzed. The experimental design can be divided into fixed sampling analysis and mobile carts analysis. In this experiment, distance and traffic period are used as operational variables, combined with low-cost sensor(LCS), to analyze pollutants including carbon monoxide, carbon dioxide, ultrafine suspended particles (PM1.0), fine suspended particles (PM2.5) This study analyzes a variety of pollutants, which mainly focusing on the characteristics of pollutant emissions from tunnel traffic, measuring particle number concentration and particle size distribution, and then establish the local emission data. Combined with the traffic flow count data, the emission factors of different vehicle types are obtained by multiple regression. The change of the vehicle flow emission factor at various distances under driving conditions are also discussed. Finally, each vehicle can be divided into gasoline vehicles (Light-duty vehicles, LDVs), Motorcycles (MC) and diesel vehicles (Heavy-duty vehicles, HDVs). The peak values of ultra-fine particles emission factor of gasoline vehicles, motorcycles, and diesel vehicles appeared at 23.3 nm, 25.9 nm, and 25.9 nm, respectively. The emission factors were 0.26±0.1, 0.21±0.08, 1.49±0.61 1015#/kg-fuel. The emission factor of gasoline vehicles and motorcycles is close, but the emission factor of diesel vehicles is 5.7 times than gasoline vehicles, which is a major source of pollution emission contribution. Therefore, even the composition of diesel vehicles is relatively low in Taiwan, the pollution caused by diesel vehicles cannot be ignored.