Department of Civil Engineering, Sharif University of Technology, Azadi Ave, P.O. Box 11155-9313, Tehran, Iran.
Department of Civil Engineering, Sharif University of Technology, Azadi Ave, P.O. Box 11155-9313, Tehran, Iran.
Sci Total Environ. 2015 Dec 15;538:375-84. doi: 10.1016/j.scitotenv.2015.07.141. Epub 2015 Aug 25.
A field sampling campaign was implemented to evaluate the variation in air pollutants levels near a highway in Tehran, Iran (Hemmat highway). The field measurements were used to estimate road link-based emission factors for average vehicle fleet. These factors were compared with results of an in tunnel measurement campaign (in Resalat tunnel). Roadside and in-tunnel measurements of carbon monoxide (CO) and size-fractionated particulate matter (PM) were conducted during the field campaign. The concentration gradient diagrams showed exponential decay, which represented a substantial decay, more than 50-80%, in air pollutants level in a distance between 100 and 150meters (m) of the highway. The changes in particle size distribution by distancing from highway were also captured and evaluated. The results showed particle size distribution shifted to larger size particles by distancing from highway. The empirical emission factors were obtained by using the roadside and in tunnel measurements with a hypothetical box model, floating machine model, CALINE4, CT-EMFAC or COPERT. Average CO emission factors were estimated to be in a range of 4 to 12g/km, and those of PM10 were 0.1 to 0.2g/km, depending on traffic conditions. Variations of these emission factors under real working condition with speeds were determined.
在伊朗德黑兰（Hemmat 高速公路）的一条公路附近，进行了一次实地采样活动，以评估空气污染物水平的变化。实地测量用于估算平均车队的基于道路路段的排放因子。这些因子与隧道内测量活动（Resalat 隧道）的结果进行了比较。在实地考察期间，进行了路边和隧道内一氧化碳（CO）和粒径分级颗粒物（PM）的测量。浓度梯度图显示出指数衰减，这代表在公路 100 至 150 米范围内，空气污染物水平有很大的衰减，超过 50-80%。还捕获并评估了从公路到不同距离处的颗粒物尺寸分布的变化。结果表明，随着与公路的距离增加，颗粒物尺寸分布向较大粒径的颗粒物转移。通过使用路边和隧道测量值以及假设的箱模型、浮动机模型、CALINE4、CT-EMFAC 或 COPERT，获得了经验排放因子。平均 CO 排放因子估计在 4 至 12g/km 之间，PM10 的排放因子在 0.1 至 0.2g/km 之间，具体取决于交通状况。确定了这些排放因子在实际工作条件下随速度的变化。
