DPF和CDPF主动再生排放特性对比分析

Comparative Analysis of Emission Characteristics ofDPF and CDPF Active Regeneration

基于外加热源再生台架和颗粒物加载装置,探究了不同再生温度和碳载量下柴油机颗粒捕集器(DPF)和催化型DPF(CDPF)主动再生时出口气体和颗粒物排放特性.结果表明:催化剂铂(Pt)的涂敷有利于碳黑(PU)的氧化,在相同碳载量条件下,CDPF更易产生温度波峰,且再生效率略高于DPF;DPF再生过程中伴随着较高体积分数的CO排放,且升温阶段会出现一个低浓度的核模态颗粒排放窗口,后续再生阶段几乎无颗粒物释放;CDPF再生过程中几乎没有CO生成,但在再生阶段会伴随着大量的30 nm以下的小颗粒释放,且随着再生温度和碳载量的升高,CDPF出口颗粒物浓度逐渐升高.DPF和CDPF再生时分别具有不同优化窗口,既有利于减少颗粒物排放同时又保持较高的再生效率.

Based on the external heating source regeneration bench and particle loading device,the emission characteristics of outlet gas and particle during active regeneration of diesel particulate filter(DPF)and catalytic DPF(CDPF)under different regeneration temperature and carbon(Printex-U,PU)loading were studied.The results show that the coating of catalyst(Pt)is conducive to the oxidation of PU.Under the same PU loading,CDPF is more likely to produce temperature peaks,and the regeneration efficiency is slightly higher than DPF.DPF regeneration process is accompanied by higher volume fraction CO emission,and a lower concentration nuclear mode particles emission window will appear in the heating stage,and there is almost no particle release in the subsequent regeneration stage.There is almost no CO generation in the regeneration process of CDPF,but a large number of small particles below 30 nm will be released in the regeneration stage,and the particle concentration at the outlet of CDPF will gradually increase with the increase of regeneration temperature and PU loading.DPF and CDPF have different optimization windows during regeneration,which is conducive to reducing particulate emissions and maintaining high regeneration efficiency.