大气有机颗粒物的在线源解析与动态定量方法体系建立

Air pollution of particulate matter is a severe problem in China. However, the sources are still not well known, in particular for particulate organic matter (POM). The offline source apportionment is time consuming, hindering rapid identification of the main sources and therefore the effective control. This proposal aims at the dynamic source apportionment for POM. A set of online instruments including a time of flight aerosol chemical speciation monitoring (ToF-ACSM) will be deployed at the Guanzhong basin, Beijing and Shijiazhuang, which will provide high time resolution (5-10 min) PM2.5 mass concentration of main chemical composition and the mass spectrometric fingerprint of POM. A dynamic source apportionment model (moving PMF, M-PMF) will be developed using new algorithm including a-value constrain, window splitting and rolling. Some key issues related to the M-PMF will be studied, including rapid identification of primary emission sources, dynamic characterization of secondary organics and the online evaluation of source apportionment results. Comprehensive evaluation of the apportionment results from multiple approaches (e.g., online v.s. offline, dynamic v.s. static) will be performed to optimize the online dynamic approach (time resolution <1 hour) for POM source apportionment in China.

我国颗粒物污染严重，来源复杂，尤其对有机颗粒物这一关键组分的来源与成因的认识还很不清楚。颗粒物源解析的非实时性限制了对污染来源的快速识别与有效控制。本项目围绕有机颗粒物在线“动态”源解析这一目标，建立以气溶胶飞行时间质谱仪（ToF-ACSM）为核心的高时间分辨率大气污染物在线测量体系。通过在关中、北京和石家庄对象区域开展外场观测，获得5-10分钟分辨率的PM2.5主要成分质量浓度和有机颗粒物质谱指纹信息。通过对已知一次污染源质谱指纹进行a值约束与校正、窗口切割与滚动计算，开发在线“动态”源解析新算法moving PMF (M-PMF)，并对“动态”解析存在的关键问题开展研究，包括一次排放源快速识别、二次生成源“动态”表征、解析结果合理性性在线评估。通过对在线与离线、动态与静态多模式解析结果进行综合校验和参数优化，建立适用于我国污染特征的有机颗粒物在线动态 (<1小时) 源解析新方法体系。

我国颗粒物污染严重，来源复杂，尤其对有机颗粒物这一关键组分的来源与成因的认识还很不清楚。颗粒物源解析的非实时性限制了对污染来源的快速识别与有效控制。本项目围绕有机颗粒物在线“动态”源解析这一目标，建立以气溶胶飞行时间质谱仪（ToF-ACSM）为核心的高时间分辨率大气污染物在线测量体系。通过在关中、北京和石家庄对象区域开展外场观测，获得了5-10分钟分辨率的PM2.5主要成分质量浓度和有机颗粒物质谱指纹信息。通过对已知一次污染源质谱指纹进行a值约束与校正、窗口切割与滚动计算，开发在线“动态”源解析新算法moving PMF (M-PMF)，并对“动态”解析存在的关键问题开展了一系列研究，包括一次排放源快速识别、二次生成源“动态”表征、解析结果合理性性在线评估。通过对在线与离线、动态与静态多模式解析结果进行综合校验和参数优化，建立了适用于我国污染特征的有机颗粒物在线动态 (<1小时) 源解析新方法体系。