Istituto Motori of National Council of Research, viale Marconi, 8, 80125 Naples, Italy.
Sci Total Environ. 2014 Jan 15;468-469:1043-9. doi: 10.1016/j.scitotenv.2013.09.025. Epub 2013 Oct 4.
Powered two-wheeler (PTW) vehicles complying with recent European type approval standards (stages Euro 2 and Euro 3) were tested on chassis dynamometer in order to measure exhaust emissions of about 25 volatile organic compounds (VOCs) in the range C1-C7, including carcinogenic compounds as benzene and 1,3-butadiene. The fleet consists of a moped (engine capacity ≤ 50 cm(3)) and three fuel injection motorcycles of different engine capacities (150, 300 and 400 cm(3)). Different driving conditions were tested (US FPT cycle, constant speed). Due to the poor control of the combustion and catalyst efficiency, moped is the highest pollutant emitter. In fact, fuel injection strategy and three way catalyst with lambda sensor are able to reduce VOC motorcycles' emission of about one order of magnitude with respect to moped. Cold start effect, that is crucial for the assessment of actual emission of PTWs in urban areas, was significant: 30-51% of extra emission for methane. In the investigated speed range, moped showed a significant maximum of VOC emission factor at minimum speed (10 km/h) and a slightly decreasing trend from 20 to 60 km/h; motorcycles showed on the average a less significant peak at 10 km/h, a minimum at 30-40 km/h and then an increasing trend with a maximum emission factor at 90 km/h. Carcinogenic VOCs show the same pattern of total VOCs. Ozone Formation Potential (OFP) was estimated by using Maximum Incremental Reactivity scale. The greatest contribution to tropospheric ozone formation comes from alkenes group which account for 50-80% to the total OFP. VOC contribution effect on greenhouse effect is negligible with respect to CO2 emitted.
为了测量约 25 种挥发性有机化合物（VOC）在 C1-C7 范围内的排放，包括致癌化合物苯和 1,3-丁二烯，对符合最新欧洲型式认证标准（欧 2 和欧 3 阶段）的两轮助力车（PTW）车辆在底盘测功机上进行了测试。该车队由一辆轻便摩托车（发动机排量≤50cm³）和三辆不同发动机排量（150、300 和 400cm³）的燃油喷射摩托车组成。测试了不同的驾驶条件（美国 FPT 循环，恒速）。由于燃烧和催化剂效率控制不佳，轻便摩托车是最高的污染物排放源。事实上，燃油喷射策略和带有 lambda 传感器的三元催化剂能够将 VOC 摩托车的排放量相对于轻便摩托车减少约一个数量级。冷启动效应对于评估 PTWs 在城市地区的实际排放至关重要：甲烷额外排放增加 30-51%。在所研究的速度范围内，轻便摩托车在最低速度（10km/h）下显示出挥发性有机化合物排放因子的显著最大值，并且从 20km/h 到 60km/h 略有下降趋势；摩托车平均在 10km/h 处显示出较小的峰值，在 30-40km/h 处达到最小值，然后随着 90km/h 时排放因子的最大值呈上升趋势。致癌 VOCs 呈现出与总 VOCs 相同的模式。使用最大增量反应性标度估算臭氧形成潜力（OFP）。对对流层臭氧形成的最大贡献来自烯烃组，占总 OFP 的 50-80%。与 CO2 排放相比，VOC 对温室效应的贡献可以忽略不计。
