天津市冬季挥发性有机物(VOCs)特征分析

Characteristics of Volatile Organic Compounds (VOCs) in Winter of Tianjin

摘要: 对天津市区冬季挥发性有机物(VOCs)进行连续在线观测，分析其冬季污染特征。结果表明：56种检出VOCS平均浓度为69.66 μg/m³，其中烷烃(50.34%) > 芳香烃(29.76%) >烯烃(16.53%) > 炔烃(3.38%)，与夏季相比，各组分贡献相对稳定，但不同物种变化差异较为明显。天津市区异戊二烯浓度变化不大，受天然源影响较小。重污染天气中各VOCs物种来保持源稳定。用B/T值衡量机动车尾气贡献，天津市区冬季受机动车影响较弱。

Abstract: In this study, we conducted a continuous online observation as well as analyzed the pollution cha-racteristics of volatile organic compounds (VOCs) which exited in Tianjin urban area in winter. Results indicated that the average concentration of 56 kinds of VOCs detected was 69.66 μg/m³, of which the alkanes (50.34%) > aromatic hydrocarbons (29.76%) > alkenes (16.53%) > alkynes (3.38%). Compared with summer, the contribution of each component is relatively stable, but the difference between different species is more obvious. The concentration of isoprene in Tianjin urban area did not change much and was less affected by natural sources. The VOCs species in heavily polluted weather kept the source stable. Tianjin urban area is less affected by motor vehicles in winter when using the B/T value to measure the vehicle exhaust gas contribution.