不同类型的尿素溶液对废气颗粒数量排放的影响
Haohao Wang1, Tianyu Zhai2, Lijun Zhang1
1Weichai Power Co., Ltd., Weifang, 261061, People's Republic of China.
Environmental science and pollution research international
|September 27, 2023
概括
将尿素溶液添加到柴油发动机中明显增加了颗粒数排放,其影响因尿素类型而异. 尿素溶液中的金属含量显著影响颗粒数量排放因子.
科学领域:
- 汽车工程 汽车工程
- 环境科学 环境科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 柴油发动机是颗粒物 (PM) 排放的主要来源.
- 尿素在水中的溶液通常用作柴油排气液 (DEF),以减少氧化 (NOx).
- DEF对粒子数 (PN) 排放的影响需要进一步调查.
研究的目的:
- 质量评估不同水中的尿素溶液对柴油发动机颗粒数排放的影响.
- 为了确定哪些尿素类型对PN排放产生最重要的影响.
- 了解尿素溶液成分和PN排放因子之间的关系.
主要方法:
- 一个柴油发动机被 subjected to bench testing. 柴油发动机被 subjected to bench testing. 柴油发动机被 subjected to bench testing. 柴油发动机被 subjected to bench testing. 柴油发动机被 subjected to bench testing. 柴油发动机被 subjected to bench testing. 柴油发动机被 subjected to bench testing.
- 他们注射了五种不同类型的尿素在水中的溶液.
- 测量了即时颗粒度和颗粒大小分布.
- 粒子数 (PN) 排放因子为每个尿素类型计算.
主要成果:
- 与基线相比,即时颗粒度在注射尿素与水溶液时显著增加.
- 颗粒度的增加是没有溶液的0.3至1.2倍.
- 高速发动机运行显示了颗粒度的显著上升,特别是与尿素溶液C和E.
- 颗粒大小分布在尿素溶液剂量方面基本没有变化.
- PN排放因子因尿素类型而异,其序列为C > E > A > B > D.
结论:
- 在水中注射尿素溶液显然增加了柴油发动机中的颗粒数排放.
- 水中的尿素溶液中的金属元素含量是影响PN排放因子的关键因素.
- 未来的研究应该优先考虑了解与注射尿素在水溶液相关的粒子形成机制.
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