山西省四城市空气颗粒物中碳的组成特征

Characteristics of carbon composition in airborne particulate in four cities of Shanxi

通过比较空气颗粒物与其排放源中总碳同位素组成及有机碳、元素碳浓度特征,并分析其相关性,探讨了山西省太原、晋城、长治和潞城等4个城市空气颗粒物中碳的来源.采集4个城市采暖季与非采暖季煤烟尘、机动车尾气尘、土壤风沙尘、城市扬尘样品与不同功能区环境空气颗粒物样品,将采集的样品经过前处理,通过热光碳分析仪测定总碳与有机碳的质量浓度,NC-2500元素分析仪与同位素质谱联机测定总碳同位素组成.结果表明:4个城市采暖季总碳主要来源于煤燃烧产生的烟尘,非采暖季则主要来源于城市扬尘;燃煤及机动车尾气排放对总碳贡献较大,其次是城市扬尘.

The concentration of organic carbon（OC）,elementary carbon（EC） and isotopic composition of total carbon（TC） in airborne particulate and pollution sources were studied which were sampled in Taiyuan,Jincheng,Changzhi and Lucheng city of Shanxi province.By analyzing the velative data of OC/EC and comparing the carbon isotopic composition of TC in airborne particulate and pollution sources,the sources of carbon in airborne particulate in the four cities were discussed.The coal-combustion dust,vehicle exhaust dust,soil dust,urban raised dust and airborne particulate in different functional sites in the four cities were collected in the heating and non-heating period.After pre-treatment,the samples were analyzed by thermal optical carbon analyzer,NC-2500 elemental analyzer and isotope mass spectrometry.The analyzing results of airborne particle and emission sources indicate that the TC of ambient samples in heating period is mainly from coal-combustion dust,while in non-heating period it is mainly from urban dust;coal-combustion dust and vehicle exhaust dust are the main emission sources of TC,and urban dust also has some contribution.