摘要
为探究低温等离子体(non-thermal plasma,NTP)对无外加热源的柴油机颗粒捕集器(diesel particulate filter,DPF)的再生过程与再生效果,搭建了排气余热辅助NTP再生DPF的试验系统。借助发动机停机后的排气余热,利用DBD(dielectric barrier discharge)型NTP发生器,对处于降温过程的DPF进行再生试验研究。结果表明:随着DPF温度的下降,NTP中O3的分解反应减弱,PM(particulate matter)氧化反应加剧,DPF内部出现温度不降反升的现象,氧化区域自DPF前端逐渐向后端延伸,DPF径向中点处氧化反应最为剧烈,DPF轴向剖面上残余积碳呈现?形。再生后DPF内部残余积碳中可溶性有机成分SOF(soluble organic fraction)明显减少,且NTP处理能够降低PM中SOF及DS(dry soot)的表观活化能。整个再生过程中,DPF内部大量积碳被氧化去除。排气余热辅助的NTP再生技术,实现了对无外加热源的DPF的有效再生,使得DPF排气背压下降达69%。该文证实了排气余热辅助NTP再生DPF的可行性,为NTP再生DPF技术的应用提供了试验依据。
Diesel engines are widely applied in the field of transportation and manufacturing because of their dynamic and economic performance. Compared to gasoline engine, the hydrocarbon （HC） and carbon monoxide （CO） emissions from diesel engine are much lower. However, diesel engine emits huge quantities of particulate matter （PM） which pose a great threat to human health and environmental protection. As emission regulations are becoming gradually stricter, it is imperative to stringently control diesel PM emission with a feasible after-treatment technic. The technology of diesel particulate filter （DPF） is considered as the most effective mean to reduce diesel PM emission. The key of DPF technology is regeneration of the DPF, which is to timely remove the carbon deposit captured by DPF. Non-thermal plasma （NTP） technology is a promising method to control diesel emission. Reactive species generated by NTP reactor can activate complicated chemical reactions under common condition. Therefore, NTP technology has been used to remove PM deposited in DPF and become a new research hotspot in the field of DPF regeneration. Other studies have shown DPF could be effectively regenerated by NTP when the regeneration temperature was precisely controlled by an extra heater. In this work, an experimental system of DPF regeneration was constructed to investigate the regeneration effect in which DPF was not heated by an external heat source. Aided by the exhaust waste heat after engine outage, an experimental study on DPF regeneration was conducted by using a dielectric barrier discharge （DBD） NTP reactor. In the process of DPF regeneration, reactive species and PM generated exothermic oxidation reactions. Infrared gas analyzer was used to measure the volume fraction of CO and CO2 that were the main oxidation products in DPF regeneration. Twelve pairs of thermocouples were distributed in the interior of DPF to monitor the temperature change in the regeneration process. Based on NTP technology aided by exhaust was
作者
濮晓宇
蔡忆昔
施蕴曦
王静
顾林波
田晶
崔应欣
Pu Xiaoyu Cai Yixi Shi Yunxi Wang Jing Gu Linbo Tian Jing Cui Yingxin(School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2017年第14期70-77,共8页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金项目(51676089)
江苏省高校自然科学研究重大项目(16KJA470002)
江苏省高校优势学科建设资助项目(PAPD)
关键词
柴油机
排放控制
试验
低温等离子体
柴油机颗粒捕集器
再生
排气余热
表观活化能
diesel engines
emission control
experiments
non-thermal plasma
diesel particulate filter
regeneration
exhaust waste heat
apparent activation energy
