机动车排放是城市VOCs的主要来源之一，随着尾气排放标准的升级，蒸发排放的比重持续上升。由于本地化测试的不足，系统性的蒸发排放研究存在缺失。主要表现为缺乏针对我国车队实际控制水平和油品情况的基础排放水平研究；缺乏能代表真实蒸发排放过程的VOCs源谱；现有模型未考虑车辆真实连续运行状态带来的影响，无法计算我国机动车真实停驶活动水平下的排放。 本研究使用密闭舱开展了154次系统性的交叉法规测试规程的正交实验，实验涉及10辆、3类排放标准车，2种普通汽油及3种不同组分构成的E10乙醇汽油，美国标准测试方法和中国标准测试方法2类测试规程，5类蒸发排放过程。建立了基于车辆和油品类型的蒸发排放因子库，将蒸发排放VOCs的物种识别由原有的静态统计推进到基于排放过程和主导机制的精细化源谱。从排放特征看，国4/5车排放水平位于美国排放标准Tier 0~Tier 1之间，热浸、渗透和加油排放因子分别为美国排放标准Tier 2车的1.1、2.7和70.6倍。从以渗透排放为主导到以碳罐排放为主导的排放机制转变是国标车仅能在国标测试下达标的原因。停车前行驶中的碳罐脱附效率是影响蒸发排放的关键因素，法规的缺陷将导致现行排放控制策略的失效。排放标准的影响大于油品的影响，油品的最终影响是多个影响过程的叠加。对蒸发排放物种，由于蒸发排放存在多个过程，且各个过程的物种构成差异明显，单一过程的物种特征不能代表蒸发排放的总体特征，之前普遍使用顶空油气谱代表蒸发排放存在缺陷，需要使用分过程排放量对过程源谱加权以获得综合源谱。 建立基于“行驶-驻车-行驶”链式行为解析的机动车VOCs全过程排放模型，实现有限基础参数及活动水平数据输入下的热浸排放、分子渗透排放、通气渗透排放、加油排放、碳罐排放、运行损失等蒸发排放过程及启动排放、热稳定运行排放等尾气排放的全过程模拟。2015年全国微型及小型汽油车共排放VOCs 1463.7±231.8 Gg，其中蒸发排放占比28.4%，热稳定运行排放占比37.1%，启动排放占比34.5%。全国分月排放量相较于全年平均值波动约±15%，各省排放总量波动20.0%~58.2%。国6标准可使单车蒸发排放因子平均降低79.0%。预计未来微型及小型汽油车VOCs排放整体呈逐年下降趋势，但是从2019年开始，蒸发排放将超过尾气排放且在2020年达到峰值665.0 Gg。到2030年排放相对2015年预计实现减排54%，其中蒸发排放相对2015年降低34%，比峰值降低59%。

Vehicle-related emissions are widely recognized as the main source of anthropogenic volatile organic compounds (VOCs) in urban areas. With the control of tailpipe exhaust emissions, evaporation loss constitutes an increasing share of the VOC emissions inventory and impacts both air quality and energy. However, due to the lack of localized data, systematic researches on evaporative emissions are inadequate in China: lack of the basic emission factors under the actual control level and fuel used in China, lack of the detailed species profiles of emissin processes. Besieds, the existing model does not take into account the impact of the trip chaining of the vehicles, and thus cannot calculate the emissions at the level of real driving and parking activity.A total of 154 crossover tests were conducted in a gastight Imtech variable-temperature SHED (VT-SHED). These crossover tests covered ten vehicles of three technical categories, five types of fuel, five evaporation processes, and two regulatory authorities’ testing procedures. Consequently, an evaporative emission factor and species profile database based on diversified vehicles and fuel type has been established, promoting the understanding of species from species based on static test processes to dynamic profiles based actural emission processes. Given the fact that China 4/5 vehicles could only meet the limited value during China 24-hour test owing to the dominated emission process changed from permeation to canister venting. The desorption of canisters during the driving cycles before parking is a key factor affecting evaporative emissions, and the defects of the regulations will lead to the failure of the current emission control strategy. an upgrade on emission standard could dramatically reduce the total emission amount and the effects due to fuel composition difference can be ignored.For evaporative emission species, there are various processes due to evaporative emissions, and the species composition of each process is significantly different. The specie profile of one single evaporative emission process cannot represent the overall characteristics of evaporative emissions, the comprehensive profiles should be caculated using the detailed emission processed based profiles and actual emission amount.In addition, this study has established a vehicle-wide VOCs full-process emission chain model based on the “driving-park-driving” chain behavior, estimating hot soak emissions, static permeation emissions, venting permeation emissions, venting of the canister and refueling emissions. Start emissons and hot running emissions were also estimated using the chain model. In 2015, the total emission of VOCs for micro- and small-sized vehicles nationwide was 1463.7±231.8 Gg, while evaporative emissions occupied 28.4%, hot running emissions contributed 37.1%, and start emissions contributed 34.5%. The national monthly emissions fluctuated by about ±15% compared to the annual average, and the total amount of the provinces fluctuated by 20.0% to 58.2%. The average evaporation factor of the China 6 vehicle can be reduced by 79.0% on average. It is expected that the overall VOCs emissions of micro and small gasoline vehicles will decline year by year. But the evaporative emissions will exceed the exhaust VOCs emissions from 2019 and reach a peak of 665.0 Gg in 2020. By 2030, VOCs emissions from micro and small gasolin vehicles in China can achieve a reduction of 54%, with evaporative emissions reduced by 39% compared with evaporative emissions in 2015 and 59% compared with the peak value.