稀释倍数对民用燃煤排放粒子老化及细粒子中多环芳烃的影响

项目名称： 稀释倍数对民用燃煤排放粒子老化及细粒子中多环芳烃的影响

项目编号： No.41305119

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 孔少飞

作者单位： 南京信息工程大学

项目金额： 25万元

中文摘要： 大气细颗粒中PAHs严重危害人体健康，民用燃煤燃烧是其最重要的来源之一。稀释通道采样方法能更加真实地反应民用燃煤燃烧烟气中颗粒的排放状况，而稀释倍数是影响烟气中颗粒浓度和粒径分布的一个重要因素。本研究采用自主搭建的稀释通道采样系统，通过设置不同稀释倍数，采用宽范围颗粒粒径谱仪讨论烟气粒子粒数浓度和粒径分布特征及稀释倍数对烟气粒子老化过程的影响，获得相应的成核增长速率，确定最佳稀释倍数；采用单颗粒气溶胶质谱对民用燃煤燃烧排放不同粒径颗粒中化学组分的演化趋势进行监测分析，分析烟气粒子的老化机制；采用五级采样头并结合烟气流速、燃料消耗量等获得不同粒径细颗粒中PAHs排放因子，分析稀释倍数对细颗粒中PAHs组成的影响。本研究可为识别民用燃煤排放烟气中粒子的老化机制、建立稀释通道采样方法在燃烧源排放颗粒监测中最佳稀释倍数的确定方法及为大气细颗粒中PAHs排放清单的建立提供参考和借鉴。

中文关键词： 民用燃煤；气溶胶；排放因子；老化；多环芳烃

英文摘要： With domestic coal combustion (DCC) as one of the most important sources,Polycyclic Aromatic Hydrocarbons (PAHs) in atmospheric fine particulate matter (PM2.5) exhibited negative impacts on human health. For studies on PM emitted from DCC, dilution sampling method is believed that it can simulate the real emission conditions of particles in smoke.Based on a self-designed dilution sampling system, the number concentrations and size distribution of particles, the growth rates of particles by nucleation under various dilution ratios (DR) and the influence of DR on the aging courses were analyzed by using a wide-range particle spectrometer (WPS). The best DR will be assured. The evolution trends of chemical species in different size of particles and the aging mechanism were studied by a Single Particle Aerosol Mass Spectrometer (SPAMS). Emission factors (EFs) for PAHs in five size-differentiated fine particles were established combined with the information of flow rates of smoke and coal consumption rates by adopting an individual five-size sampling inlets. The influence of DR on the EFs of PAHs was analyzed. This research will be useful to identify the aging mechanism of particles in smoke emitted from DCC and to establish the method for ascertaining the best DR of dilution sampling for combustion sources monitorin

英文关键词： domestic coal；aerosol；emission factor；aging；Polycyclic Aromatic Hydrocarbons