在高O3期间,使用初始VOC度-分散正常化PMF的来源分配VOC的变化
Yutong Wu1, Baoshuang Liu1, He Meng2
1State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control & Tianjin Key Laboratory of Urban Transport Emission Research, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health Research, Tianjin 300350, China.
The Science of the total environment
|June 29, 2023
概括
一种新方法,初始度-分散规范化PMF (ICDN-PMF),准确量化挥发性有机化合物 (VOC) 的来源. 控制溶剂使用和机动车辆是减少臭氧污染期间VOCs的关键.
科学领域:
- 环境化学环境化学
- 大气科学 大气科学
- 监测空气污染 监测空气污染
背景情况:
- 环境中的挥发性有机化合物 (VOC) 度受到排放,大气分散和化学变化的复杂相互作用的影响.
- 准确的VOC来源分配对于有效的空气质量管理至关重要,特别是在臭氧污染高的时期.
研究的目的:
- 开发和验证一种新的方法,即初始度-分散规范化正矩阵因数分解 (ICDN-PMF),以改进VOC源分配.
- 评估光化学损失和大气分散在臭氧污染 (OP) 和非臭氧污染 (NOP) 期间对VOC源贡献的影响.
主要方法:
- 开发ICDN-PMF模型,以纠正光化学损失,并将大气分散效应正常化.
- 将ICDN-PMF方法应用于2020年3月至5月在青岛收集的每小时指定VOC数据.
- 在OP和NOP期间对VOC来源贡献的比较分析.
主要成果:
- 与NOP相比,ICDN-PMF方法有效地纠正了OP期间低估的溶剂使用和生物源排放,显示分别增加了4.4倍和3.8倍.
- 由于空气分散,OP期间溶剂使用贡献增加了4.6倍. 在OP期间挥发性有机物的主要贡献者是生物源排放 (23.1%),溶剂使用 (23.0%),机动车辆排放 (17.1%),以及天然气/柴油蒸发 (15.8%).
- 在OP期间,生物和溶剂使用的贡献显著增加 (分别为187%和135%),而液化石油气的贡献则下降.
结论:
- ICDN-PMF模型提供了对VOC来源贡献的更准确的评估,特别是通过计算化学和物理大气过程.
- 建议针对性控制战略,重点关注溶剂使用和机动车辆,以减轻臭氧污染事件期间的VOC污染.
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