杭州市大气PM2.5和PM10污染特征及来源解析

2006年在杭州市两个环境受体点位采集不同季节大气中PM_2.5和PM₁₀样品,同时采集了多种颗粒物源类样品,分析了其质量浓度和多种化学成分,包括21种无机元素、5种无机水溶性离子以及有机碳和元素碳等,并据此构建了杭州市PM_2.5和PM₁₀的源与受体化学成分谱;用化学质量平衡(CMB)受体模型解析其来源。结果表明,杭州市PM_2.5和PM₁₀污染较严重,其年均浓度分别为77.5μg/m³和111.0μg/m³;各主要源类对PM_2.5的贡献率依次为机动车尾气尘21.6%、硫酸盐18.8%、煤烟尘16.7%、燃油尘10.2%、硝酸盐9.9%、土壤尘8.2%、建筑水泥尘4.0%、海盐粒子1.5%。各主要源类对PM₁₀贡献率依次为土壤尘17.0%、机动车尾气尘16.9%、硫酸盐14.3%、煤烟尘13.9%、硝酸盐粒8.2%、建筑水泥尘8.0%、燃油尘5.5%、海盐粒子3.4%、冶金尘3.2%。

Characterization and Source Apportionment of PM2.5 and PM10 in Hangzhou

The samples for PM_2.5 and PM₁₀ were collected in 2006 at two sites in Hangzhou.The mass concentrations of the ambient air particles and their chemical species were obtained. The chemical mass balance method had been applied to identify the source of PM_2.5 and PM₁₀. The results of the source apportionment show that the major contributions of PM_2.5 aerosol mass in Hangzhou include: motor vehicle exhausts 21.6%, sulfate 18.8%, coal combustion 16.7%, burning oil combustion 10.2%, nitrates 9.9%, soil dusts 8.2%, cement dust 4.0%, sea salt particles 1.5%. The major contributions of PM₁₀ aerosols include: soil dusts 17.0%, motor vehicle exhausts 16.9%, sulfate 14.3%, coal combustion 13.9%, nitrates 8.2%, cement dust 8.0%, burning oil combustion 5.5%, and sea salt particles 3.4%.