春节期间西安城区碳气溶胶污染特征研究

Study on Pollution Characteristics of Carbonaceous Aerosols in Xi'an City During the Spring Festival

采用美国R&P公司TEOM-1400a大气颗粒物监测仪器及其8通道采样系统(ACCU),在2011年春节期间实时监测和分8个时段采集了西安城区的PM2.5样品.研究了春节期间西安城区大气中PM2.5的碳气溶胶污染特征.目的是阐明2011年春节期间燃放烟花爆竹时,西安城区大气中细颗粒PM2.5的质量浓度、元素碳(EC)、有机碳(OC)及水溶性有机碳(WSOC)的浓度分布特征,探讨了其污染来源.结果表明,除夕00:00～02:59为污染浓度最大时段,PM2.530 min平均浓度在01:00时刻达到最大值1 514.8μg·m-3,其碳组分OC、EC、WSOC、非水溶性有机碳(WIOC)分别为123.3、18.6、66.7和56.6μg·m-3,高于春节期间的其他正常时段1.7倍、1.2倍、1.4倍和2.2倍.碳气溶胶组分WSOC与OC、EC相关性分析表明春节烟火期间含碳物质更多的来自于烟花爆竹燃放,但其对烟火时段的气溶胶的贡献较小,仅为9.4%.

The samples of PM2.5 with 8 times periods were collected using Automated Cartridge Collection Unit（ACCU） of Rupprecht Patashnick（RP）Corporation,and monitored by RP1400a instrument of TEOM series online during 2011 Spring Festival in Xi＇an city.The organic carbon（OC）,elemental carbon（EC）,water-soluble organic carbon（WSOC） and water-insoluble organic carbon（WIOC） contents of 3 h integrated PM2.5 were analyzed to evaluate the influence of firework display on the carbonaceous components in urban air.The mass concentration of PM2.5 was found increased significantly from 00：00 A.M.to 02：59 A.M.at the Chinese Lunar New Year＇s Eve than the non-firework periods,reaching 1 514.8 μg·m-3 at 01：00 A.M.The mass concentrations of OC,EC,WSOC,and WIOC during the same time period were 123.3 μg·m-3,18.6 μg·m-3,66.7 μg·m-3,and 56.6 μg·m-3,about 1.7,1.2,1.4,and 2.2 times higher than the average in normal days,respectively.Correlation analysis among WSOC,OC,and EC contents in PM2.5 showed that firework emission was an obvious source of carbonaceous aerosol in the Spring Festival vacation.However,it only contributes to 9.4% for aerosol in fireworks emission.