揭示重型柴油车的反应排放量,跨越不断变化的标准和作弊策略
Xiang Ding1, Cheng Huang2,3, Dan Dan Huang2
1Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Ministry of Ecology and Environment, Shanghai Academy of Environmental Sciences, Shanghai 200233, China.
Environmental science & technology
|December 17, 2024
概括
重型柴油车排放有反应 (Nr). 虽然选择性催化减排 (SCR) 系统减少了一些Nr,但中国VI车辆的氨滑动催化剂 (ASC) 增加了氧化 (N2O) 排放量,并改变了HONO/NOx比率.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 汽车工程 汽车工程
背景情况:
- 重型柴油车 (HDDV) 的反应性 (Nr) 排放影响空气质量和生态系统.
- 硬盘硬盘驱动器是Nr的重要来源,其复杂的排放受到驾驶条件和后处理系统的影响.
研究的目的:
- 根据中国的IV,V和VI标准,从HDDV中调查Nr物种 (NO,NO2,HONO,N2O,NH3) 的排放因子 (EF).
- 分析选择性催化减排 (SCR) 系统和氨滑动催化剂 (ASC) 对 Nr. 排放的影响.
- 评估排放控制策略与水注射等作弊方法的有效性.
主要方法:
- 通过不同中国排放标准 (IV,V,VI) 对HDDV的排放因子测试.
- 对Nr物种度的分析,包括NO,NO2,HONO,N2O和NH3.
- 在各种驾驶条件下评估SCR和ASC系统的性能和副产品的形成.
主要成果:
- 水注入作弊复制了中国III排放水平,否定了排放控制的好处.
- 中国IV,V和VI标准中的SCR系统通常可以减少NO,NO2和HONO的排放.
- 具有ASC的中国VI车辆显示NH3滑落减少,但N2O排放量增加了6至13倍 (205±85 mg/km),HONO/NOx比率更高 (4.6%).
结论:
- SCR技术已经改善了对几种Nr物种的控制,但ASC在中国VI的整合带来了N2O和HONO排放的挑战.
- 后处理系统的有效性因驾驶模式而异,需要进一步优化.
- 为了平衡所有活性物种的控制,需要先进的SCR和ASC技术.
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