不同后处理装置生物柴油发动机颗粒多环芳烃排放

Particle PAHs Emissions of Biodiesel Engine Equipped with Different After-Treatments

基于一台高压共轨柴油机,利用台架试验采样和离线分析,研究了燃用生物柴油混合燃料BD20使用不同后处理装置(DOC、DPF和CDPF)对柴油机的颗粒多环芳烃(PAHs)排放特性、成分和毒性的影响。研究结果表明:燃用生物柴油混合燃料BD20引起了柴油机颗粒物中PAHs质量比升高和颗粒物毒性增强;不同后处理装置均降低了柴油机的颗粒PAHs排放和毒性,DOC可降低颗粒PAHs排放约30%,使颗粒物毒性降低约20%;DPF和CDPF可去除排气中大部分颗粒PAHs,使颗粒物毒性降低60%以上,使排气毒性降低85%以上,可有效地实现对生物柴油发动机颗粒PAHs排放和毒性的控制。

On a common rail diesel engine fuelled with biodiesel and equipped with after-treatment de- vices, influences on particle polycyclic aromatic hydrocarbons （PAHs） emission characteristics, composition and toxicity were investigated by engine bench sampling and off-line gas chromatography mass spectrometer （GC-MS）. Results show that full biodiesel blend BD20 increases PAHs pass concentration and particle toxicity. And all the test after-treatment devices reduced PAHs emission rate and toxicity. DOC reduces PAHs mass emission by 30% and particle toxicity by 20 % and both of DPF and CDPF remove majority of PAHs mass in exhaust and then reduced particle and exhaust toxicity respectively by 60% and 85% or more, thus adopting DPF or CDPF can effectively control exhaust particle PAHs hazard from biodiesel engine.