修订轻型车辆HONO排放的估计指标
Xinping Yang1, Mingliang Fu1, Songdi Liao2
1State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Vehicle Emission Control Center, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Journal of hazardous materials
|August 28, 2024
概括
车辆排放是酸 (HONO) 的重要来源,基激素的前体. 这项研究显示,更新的排放标准显著降低了HONO,而一种新的估计方法提高了准确性.
科学领域:
- 大气化学 大气化学
- 环境科学 环境科学
- 汽车工程 汽车工程
背景情况:
- 气态酸 (HONO) 对基 (OH) 基的形成和二次污染至关重要.
- 车辆排放是主要的HONO来源,传统上使用固定比率 (RHONO/NOx = 0.8%) 估计.
- 最近的测量显示,车辆HONO排放量存在很大差异,需要精确的估计方法.
研究的目的:
- 调查不断变化的排放标准对轻型汽油汽车HONO排放因子的影响.
- 确定影响车辆排气中HONO产生的主要因素.
- 开发和验证车辆HONO排放的修改估计指标.
主要方法:
- 在代表不同排放标准的十辆轻型汽油车上进行了底盘动力仪驾驶测试 (中国IV,V,VI).
- 分析了水含量和排气温度对HONO产生的影响.
- 通过整合氧化排放和燃烧效率,开发了一种修改后的估计指标.
- 创建了特定城市区 (成都金区) 车辆HONO排放的动态清单.
主要成果:
- 在更严格的标准下,HONO排放因子显著下降:0.40 mg/km (中国IV),0.13 mg/km (中国V) 和0.06 mg/km (中国VI).
- 水含量和排气温度被确定为HONO形成的关键因素.
- 与传统方法相比,修改后的估计指标显示出更好的准确性.
- 传统的指标在研究区域高估了约17%的HONO排放量.
结论:
- 现代排放标准大大减少了轻型汽油车的HONO排放.
- 精细的估计方法,考虑到NOx和燃烧效率,对于准确的HONO预算制定至关重要.
- 这项研究改善了对汽车HONO来源的理解,并有助于减少大气模型中的不确定性.
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