京津冀大气颗粒物动态源解析关键影响因子评估与综合验证

Source apportionment is the most critical step towards pollution control, yet very challenging, with no method providing sufficiently reliable answers. The multiple time resolution particle source apportionment (MTR PM source apportionment) is a new and “dynamic” approach to identify the sources of ambient PMs with higher time resolution than the traditional way. This study will be beneficial for illustrating the formation mechanism of pollution episode more precisely, and supporting the evaluation for effect of the emergency control or abatement measures for preventing these heavy pollution episodes. This research will focus on solving some basic issues by clarifying the identification method for PM “source-receptor” relationship during its aging process, verifying MTR in different methods, which in turn, helping to improve the performance and reliability of MTR, in being dynamic, better responding to rapidly changing air characteristics, in contrast to the existing, static methods..We will firstly try to supply the solutions for testing and validating the sensitivity and accuracy of particle matter MTR source apportionment. A twin modified chamber system (one for testing and one for reference) will be built and equipped with online instruments for measuring the chemical component and single particle characteristics, in order to establish the method to recognize the profile of PMs from some typical burning processes (coal burning, traffic, bio-mass burning). And we further detect the PM physical and chemical property during its aging process and establish the “source-receptor” relationship in different period of the pollution episode. The team will also conduct field experiments to observe the heavy pollution episodes over the JJJ Region. In the selected sites, we will measure the chemical spectrum of single particles using single particle aerosol mass spectrometer, the number size distribution, chemical properties and the mixing status of the single particles, together with the online observation on water soluble ions, OC/EC, heavy metal of the fine particles. The concentrations of PM and its chemical composition, morphologies, elemental compositions, and mixing states will also be analyzed based on the bulk PM samples. This study will adopt not only the PM MTR source apportionment to identify and analyze the origination and source of particles in different period of the episodes, but also the ART method and receptor model (PMF, PCA or CMB model) to perform the source apportionment. In particular, the focus will be on establishing the relationship between the PM sources results analyzed by the “dynamic” approach and the traditional way, as well as verifying the accuracy of the former.

颗粒物动态源解析是针对大气污染过程中颗粒物来源进行多时间分辨率解析的一种新方法。该方法的发展为精细化研究颗粒物来源特征、动态评估重污染应急控制效果提供了新的技术途径。本研究拟针对颗粒物“动态”解析中存在的几个科学问题，如关键排放源识别、老化过程动态表征、解析结果综合验证等开展研究，为完善“动态”解析技术体系提供基础科学支撑。本项目拟以京津冀为对象区域开展研究，通过建立双模拟烟雾箱系统，研究典型燃烧源颗粒物老化过程中“源-受体”关系并确定其识别敏感性，定量评估新鲜排放源进入背景大气后对颗粒物“动态”解析结果的影响；依托京津冀多级观测点，基于颗粒物成分和单颗粒特征在（离）线测量，“模拟”期间真实大气重污染过程中颗粒物来源变化进行同步动态识别和定量解析；结合关键污染源“老化”敏感性评估，基于强化观测获得的颗粒物综合特征数据，利用多种源解析算法和模型验证“动态”源解析方法的准确性和可靠性。

研究团队围绕“典型源敏感性评估-典型源动态源解析-综合应用及验证”这一主线开展研究，通过实验箱模拟测试、外场在线观测与分析、模型综合集成，对基于单颗粒飞行时间质谱在线源解析方法、基于颗粒物在线组分测量的源解析方法及手工测量方法开展对比和应用；考察二次转化对于在线源解析（尤其是基于单颗粒质谱在线源解析方法）的干扰；将在线源解析技术应用于京津冀及周边地区大气重污染过程的成因分析和溯源工作；为环境管理部门提供颗粒物在线源解析方法技术导则和标准，以提供针对重污染天气中颗粒物快速动态源解析的业务化技术指导依据。. 基于本项目，研究团队在以往工作基础上，针对不同颗粒物在线组分测量技术开展了对比研究，针对单颗粒飞行时间质谱的源谱测量方法进行了评估，通过建立烟雾箱系统针对三类主要燃烧源类（燃煤、机动车、生物质燃烧）排放颗粒物的老化过程进行了分析，对两种颗粒物动态源解析方法模型进行了一定优化，在本项目开展期间，支持了生态环境部京津冀及周边颗粒物组分网建设，并基于颗粒物在线源解析技术对秋冬季重污染过程的成因分析提供了技术支持。. 根据项目立项申报书中规定的研究任务，本研究完成规定任务，完成观测内容及数据分析，并基于数据结果发表研究论文20篇，其中SCI收录9篇，中文核心11篇。依托项目研究的国家发明专利获得2017年度国家发明专利奖（优秀奖）。基于本项目，向生态环境部监测司提供分析报告60余份；基于单颗粒飞行时间质谱和颗粒物在线组分观测数据和源解析结果，开展了2016-2017、2017-2018年秋冬季京津冀及周边颗粒物来源解析分析报告编写工作，为连续两年的大气污染防治工作提供技术评估依据。标准方法建设方面，基于本项目的部分成果，建立了《颗粒物动态源解析技术指南》，并作为下一步指导环保部系统开展颗粒物动态源解析业务化工作的技术规范文件，进入生态环境部标准序列。