稀燃汽油机NO_(x)排放后处理方案的研究  

Research on NO_(x) Emission After-treatment Scheme of Lean-burn Gasoline Engine

作　　者：田一润 张淼 徐立峰 杨建 周益波 TIAN Yirun;ZHANG Miao;XU Lifeng;YANG Jian;ZHOU Yibo(Ningbo Geely Royal Engine Components Co.,Ltd.,Ningbo,Zhejiang,315336,China)

机构地区：[1]宁波吉利罗佑发动机零部件有限公司,浙江宁波315336

出　　处：《小型内燃机与车辆技术》2023年第4期62-66,77,共6页Small Internal Combustion Engine and Vehicle Technique

摘　　要：针对某稀燃汽油机,设计了新型三元催化器(NTWC)+催化型汽油机颗粒过滤捕集器(CGPF)+选择性催化还原(SCR)系统的NO_(x)排放后处理方案,并进行了新鲜态催化剂发动机台架试验验证。通过试验,对比分析了发动机分别在40℃和90℃冷却水温度时,SCR系统分别采用全液式和气助式的NO_(x)转化效率。试验结果表明:冷却水温度为40℃的情况下,采用全液式和气助式SCR系统的NO_(x)排放后处理系统,NO_(x)转化效率均达到95%及以上。冷却水温度为90℃的情况下,SCR系统前端温度小于520℃时,采用全液式和气助式SCR系统的NO_(x)排放后处理系统,NO_(x)转化效率均达到96%及以上;SCR系统前端温度大于520℃时,采用气助式SCR系统的NO_(x)排放后处理系统,NO_(x)转化效率明显高于采用全液式SCR系统的NO_(x)排放后处理系统;SCR系统前端温度大于600℃时,NO_(x)转化效率急剧下降。For a lean-burn gasoline engine,a new type of three-way catalytic converter(NTWC)+catalyzed gasoline particulate filter(CGPF)+selective catalytic reduction(SCR)system for NO_(x) emission aftertreatment was designed,and the fresh catalyst engine bench test was carried out.The NO_(x) conversion efficiency of SCR system using all-liquid and gas-assisted cooling water at 40℃and 90℃respectively was compared and analyzed through experiments.The test results show that when the cooling water temperature is 40℃,and the NO_(x) emission aftertreatment system of the all-liquid and gas-assisted SCR system are adopted respectively,the NO_(x) conversion efficiency reaches 95%or above.When the cooling water temperature is 90℃and the front end temperature of the SCR system is less than 520℃,and the NO_(x) emission aftertreatment system of the all-liquid and gas-assisted SCR system are adopted respectively,the NO_(x) conversion efficiency reaches 96%or above.When the front end temperature of SCR system is greater than 520℃,the NO_(x) conversion efficiency of gas-assisted SCR system is significantly higher than that of all-liquid SCR system.When the front end temperature of SCR system is higher than 600℃,the NO_(x) conversion efficiency decreases sharply.

关 键 词：稀燃汽油机 SCR 全液式 气助式 冷却水温度 转化效率 

分 类 号：TK411.5[动力工程及工程热物理—动力机械及工程]