兰州市大气单颗粒来源识别及应用

Source Identification of Individual Particles and Its Application to Air Quality Management in Lanzhou,China

为配合兰州市政府开展冬季大气污染防治工作,有针对性地抓住重点,降低污染源控制的社会成本,提出更有效的冬防污染源控制对策,2011年12月21—23日在兰州8个采样点共采集10个样品,对其进行电子显微镜来源解析研究。结果表明,兰州市单颗粒形态主要分为层状不规则、链状、圆球形、单体结晶体以及多形态混合型。同时在榆中工业区和西固区附近发现葡萄状和表面液态颗粒物等特征形态。兰州市的大气颗粒物主要来源于扬尘、燃煤、机动车及二次颗粒物;机动车排放颗粒物虽在各采样点均有发现,但总体上所占比例不大;榆中工业区及西固区的工业污染物可能对主城区污染产生明显影响;兰州市主城区的大气颗粒物主要来自局地的排放。建议兰州市重点加强主城区扬尘及燃煤污染控制,严格控制榆中工业区及西固区工业污染源排放。

In order to focus on the main emission sources, decrease control cost, make pollution control more efficient during winter air pollution control campaign organized by the government of Lanzhou City, 10 samples were collected for SEM analysis at 8 sampling sites in Lanzhou City during December 21-23, 2011. The results showed that individual particles in Lanzhou City could be divided into several groups： irregular particles, chain particles, round panicles, crystal particles and multi-source-particle mixture. Typical panicles of grape-like particles and liquid surface particles were found at Yuzhong Industry Park and Xigu District. The PM sources in Lanzhou City included mainly fugitive dust, coal burning, vehicle emission and secondary particles. Though vehicle emission panicles could be found at all sites in Lanzhou City, they were not the important sources at most sites. Panicles from Yuzhong Industry Park and Xigu District probably had obvious effect on the air quality of downtown Lanzhou. The panicles of downtown Lanzhou mostly came from local sources. It was suggested that fugitive dust and coal burning should be controlled strictly in downtown Lanzhou, and industry emission be controlled tightly at Yuzhong Industry Park and Xigu District.