简易瞬态工况下汽油车挥发性有机物在线排放特征研究  

Online emission characteristics of volatile organic compounds from gasoline vehicles under simple transient driving mode

作　　者：郝钰琦 沙青娥 庄文辉 卢仲康 袁自冰 赵恺辉 刘元向 段乐君 刘学辉 张立航 郑君瑜 邵敏 袁斌 李文石 王日超 闫宇 HAO Yuqi;SHA Qing′e;ZHUANG Wenhui;LU Zhongkang;YUAN Zibing;ZHAO Kaihui;LIU Yuanxiang;DUAN Lejun;LIU Xuehui;ZHANG Lihang;ZHENG Junyu;SHAO Min;YUAN Bin;LI Wenshi;WANG Richao;YAN Yu(School of Environment and Energy,South China University of Technology,Guangzhou 510006;Institute for Environmental and Climate Research,Jinan University,Guangzhou 511486;Guangzhou Huagong Motor Vehicle Inspection Technology Co.,Ltd.,Guangzhou 510641;Palmary Technology Co.,Ltd.,Beijing 100071)

机构地区：[1]华南理工大学环境与能源学院,广州510006 [2]暨南大学环境与气候研究院,广州511486 [3]广州华工机动车检测技术有限公司检测站,广州510641 [4]帕莫瑞科技有限公司,北京100071

出　　处：《环境科学学报》2020年第12期4470-4482,共13页Acta Scientiae Circumstantiae

基　　金：国家重点研发计划(No.2016YFC0202201)。

摘　　要：机动车是大气挥发性有机物(VOCs)的重要排放源之一,识别其高分辨率排放特征对于VOCs污染控制具有重要意义.针对现有研究对不同行驶状态下机动车VOCs排放特征精细化描述较为缺乏这一问题,本研究构建了在线与离线相结合的VOCs测量系统,采用底盘测功机运行的简易瞬态工况(VMAS),对广州市36辆不同排放标准的汽油车尾气VOCs高分辨率排放特征开展在线测量.实时观测结果发现,随着国标加严,VOCs排放至少下降2个数量级.庚烷、丁烯、甲苯、甲醛和甲醇为各类VOCs的特征组分,各组分间的相关系数普遍在0.90~0.97之间.然而,随着国标加严,组分间的相关系数下降到0.20~0.94,醇类与其它组分出现负相关或无相关性.VOCs排放分布集中于变速阶段,高于怠速和匀速阶段所占的比重,其中,甲醛、乙醛和丙酮等含氧挥发性有机物(OVOCs)在不同变速阶段维持较高且稳定的排放.这说明在城市地区降低机动车VOCs排放,长期任务是减少因拥堵或其它因素造成的频繁启动和变速,尽可能确保行驶畅通.本研究在线与离线测试所识别的VOCs组分比对结果一致性较高,在线仪器的使用较好地弥补了离线测试识别VOCs实时排放特征的局限性.Light gasoline vehicles are one of the most important emission sources of atmospheric volatile organic compounds(VOCs), and it is of great significance to analyze their emission characteristics for VOCs pollution control. In view of the lack of current research on the detailed description of vehicle VOCs emission characteristics under different driving conditions, this study constructed a combination of online and offline VOCs measurement system using a simple transient operating condition of chassis dynamometer operation(VMAS) and measured high-resolution emission characteristics of VOCs from 36 gasoline vehicles in Guangzhou. The study found that with the tightening of the national standard, VOCs emissions dropped by at least two orders of magnitude. Real-time observations indicated that the speed change, especially the acceleration phase, caused a significant increase in emissions. Heptane, butene, toluene, formaldehyde and methanol were the characteristic components. Correlations between components were generally 0.90~0.97. With the tightening of the national standard, the correlation decreased to 0.20~0.94, and alcohols had no or even negative correlation with other components. The distribution of the emission rate were concentrated in the shifting stage and much higher than the proportion of the idle and constant speed stages. Formaldehyde, acetaldehyde, acetone and other oxygenated VOCs maintained high and stable emissions at different speed change stages. This showed that over urban areas to reduce vehicle VOCs emissions, the long-term task is to reduce the frequent start-up and speed change caused by congestion or other factors, and to ensure smooth driving as far as possible. In this study, the comparison between the VOCs components identified by online testing and offline sampling was consistent. The use of online instruments makes up for the limitations of offline testing for identifying the real-time emission characteristics of VOCs.

关 键 词：在线测量 工况变化 挥发性有机物 排放特征 简易瞬态工况 

分 类 号：X51[环境科学与工程—环境工程] X831