厦门市隧道中挥发性有机物污染研究

Study on pollution of volatile organic compounds in tunnels in Xiamen

选择厦门市典型的7个隧道,采用三段预浓缩和气相色谱-质谱联用方法,对隧道口和隧道内空气中的VOCs进行了分析研究。结果表明:隧道内VOCs污染一般比隧道口严重,而当隧道口受到周围VOCs污染的影响时,将导致隧道口VOCs污染比隧道内严重;甲苯、乙醇、对二甲苯、邻二甲苯、1,2,4-三甲苯为本研究主要的活性组分,甲苯对隧道空气的光化学活性贡献最大;BTEX分析显示,除汽车尾气外,其它源也会对隧道内苯系物的污染有较大的影响;对隧道内和隧道口VOCs相关性分析发现,1,3-丁二烯、丙烯醛、二氯甲烷、正己烷、1,1-二氯乙烷、4-乙基甲苯、氟利昂-12、一氯甲烷的相关性较好,表明在隧道内和隧道口这些物质具有相同的来源。

In order to study the pollution of the exit and inner of traffic tunnel,VOCs Samples were collected in 7 tunnels in Xiamen and analyzed by the combinated technology of three-stage preconcentrator and GC-MS.The results indicated that VOCs pollution inside the tunnel were usually heavier than that of exit.However,the circumstance might be reversed when pollution of ambient air outside the tunnel was serious.The prevailing species with high photochemical reactivity were toluene,ethanol,p-xylene,o-xylene and 1,2,4-trimethylbenzene.Toluene covered the most proportion of photochemical reactivity for the air in tunnels.BTEX analysis showed other sources besides vehicle emission had some effect on benzene series compounds in the tunnel.It took a good relationship among 1,3-butadiene,acrolein,methylene chloride,hexane,1,1-dichloroethene,4-ethyltoluene,freon-12,and chloromethane between the exit and inner of the tunnel,which implied that these eight species both at the exit and inner of those tunnels were mainly from the same source.