基于对称固体SCR系统的真实世界的排放特征研究
Yingshuai Liu1, Jianwei Tan2, Chenxing Liu2
1Shandong Huayu University of Technology, Dezhou, China.
PloS one
|April 29, 2025
概括
固体SCR技术为柴油发动机提供了更好的NOx排放控制,特别是在寒冷的城市条件下. 该系统使用固体,克服了基系统的限制,如结和结晶,提高可靠性和减少污染.
科学领域:
- 环境科学 环境科学
- 机械工程 机械工程
- 化学工程是化学工程的重要组成部分.
背景情况:
- 柴油发动机面临高氧化物排放的挑战,特别是在城市,低温条件下,影响了尿素选择性催化降解 (SCR) 技术的有效性.
- 尿素SCR系统遭受低温问题,如结和尿素结晶,阻碍了实际城市驾驶的性能.
研究的目的:
- 为了比较一个符合中国VI标准的柴油卡车中固体SCR和尿素SCR系统的真实世界排放特性.
- 评估固体SCR技术在缓解与尿素SCR系统相关的低温操作缺陷方面的有效性.
主要方法:
- 使用便携式排放测量系统 (PEMS) 进行现实世界的车辆测试.
- 在实际操作条件下比较了一辆SAIC Hongyan垃圾车,配备了Solid SCR和Urea SCR系统.
主要成果:
- 固体SCR系统使用固体,减少与尿素相关的问题,如在低温下结冰和结晶.
- 在现实条件下,固体SCR显示NOx转换效率略有提高 (0.5%) 和NOx排放量减少8.9%与SCR相比,在特定的平均窗口温度下.
- 颗粒数 (PN) 排放显示SCR系统对任何一个系统的影响最小. 使用固体SCR系统时,随着车辆速度的增加,CO,HC,NO和NOx排放量减少.
结论:
- 固体SCR技术为柴油废气处理提供了更可靠和更有效的解决方案,特别是在寒冷的环境中.
- 固体SCR提供了更好的系统运行和适应性,有助于减少柴油车辆排放和环境污染.
- 固体SCR是一种有前途的技术,用于控制柴油发动机的NOx排放.
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