北京市交通微环境汽车尾气污染的浓度特征

Investigation on vehicular pollution level in various transport micro-environments in Beijing

对北京市典型交通微环境中(包括公交车站,公交车内以及小轿车内)的汽车尾气污染物CO、NO、NO2和PM2.5浓度进行了监测.结果表明,NO、CO和PM2.5在交通微环境中的浓度分布相似,均为公交车内浓度最高,公交车站浓度最低.NO2为公交车内浓度最高,小轿车内浓度最低.公交车内CO的早高峰浓度要显著高于晚高峰浓度,普通公交车内的CO、NO和NO2浓度均低于空调车.良好的通风条件可以显著改善公交车车内空气质量.对小轿车车内浓度的影响因素分析表明,选择车流量平峰时段出行、恰当的保养维护车辆、在车辆拥堵区域使用内循环通风模式可以有效地降低车内污染水平.

The air pollution concentration features of vehicular pollution in Beijing were investigated. CO, NO, NO2 and PM2.5 were monitored in typical transport microenvironments, including bus stop, in-bus and in-car. The distribution of NO, PM2.5 and CO concentration in microenvironments was similar. The concentrations in bus were highest, at bus stop were lowest. In bus, the CO was higher in the morning peak hours than in the afternoon peak hours. Meanwhile, CO, NO and NO2 were lower in conventional buses than in air-conditioned ones, this revealed that ventilation could improve in-bus air quality significantly. The analysis on influence factors to concentrations in cars showed that traveling in level hours, good maintenance, and using inner-circulation mode in traffic jam areas could reduce in-vehicle pollution level effectively.