人为二次有机气溶和臭氧生产从青相关的排放
Karl M Seltzer1, Venkatesh Rao1, Havala O T Pye2
1Office of Air and Radiation, U.S. Environmental Protection Agency, 109 TW Alexander Dr, Research Triangle Park, NC 27711.
概括
青排放有助于二次有机气溶 (SOA) 和臭氧的形成. 尽管减少了,但青铺路仍然是一个重要的来源,随着其他排放量下降,其相对重要性可能会增加.
科学领域:
- 环境化学环境化学
- 大气科学 大气科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 液态青是一种石油产品,在建筑中广泛使用.
- 最近的研究强调了青排放是二次有机气溶 (SOA) 前体的重要,以前被忽视的来源.
- 青中的活性有机碳化合物有助于空气污染.
研究的目的:
- 建立美国青相关排放的综合清单.
- 量化这些排放对二次有机气溶 (SOA) 和臭氧形成的影响.
- 评估青排放的历史趋势和未来相对重要性.
主要方法:
- 利用潜在的排放估计和使用数据,建立了2018年青排放的自下而上的清单.
- 采用光化学建模来估计青排放对SOA和臭氧水平在美国连续地区的影响.
- 分析了历史数据,将目前的青铺路排放量与大约50年前的排放量进行比较.
主要成果:
- 2018年,美国的青活动 (热混合,热混合,乳化,削减,屋顶) 估计释放了约380千克的有机化合物.
- 青排放可能会使大城市的夏季SOA增加0.1-0.2μg m-3,在某些日子中午可能达到0.5μg m-3.
- 对模拟的臭氧水平的影响通常很小,约为0.1 ppb.
- 与50年前相比,青铺路排放量减少了约50%,主要是由于减少了削减青的使用.
结论:
- 青排放是SOA前体的重要来源,影响城市空气质量.
- 虽然青的历史排放量有所下降,但随着移动源排放量的减少,它们对城市SOA的相对贡献可能会增加.
- 对青相关排放的持续监测和缓解策略对于空气质量管理至关重要.
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