【摘要】 在一台直喷式柴油机上,采用玻璃纤维滤纸及XAD-2吸附管采集、超声和索氏提取、气质联用分析等技术,测量了燃用柴油、生物柴油及其调合油B50排气中的多环芳烃类污染物(PAHs).研究表明,柴油机颗粒相PAHs排放随着负荷的增大呈现降低的趋势,气相PAHs排放随着负荷呈现先降低后升高的趋势.与柴油相比,生物柴油的颗粒相和气相PAHs排放有所降低,其平均排放浓度也均低于柴油.生物柴油排气中总PAHs排放浓度为41.1～70.1μg/m3,总PAHs的平均排放浓度与柴油相比下降了33.3%.3种不同燃料的三环PAHs排放均占总PAHs排放量的44%左右,生物柴油的三环PAHs所占比例要高于柴油.生物柴油排放的PAHs毒性当量与柴油相比有较大程度的降低,表明燃用生物柴油对人体的危害性有所降低.更多还原

【Abstract】 The polycyclic aromatic hydrocarbons(PAHs) were measured by glass fiber filter and XAD-2 collector,ultrasonic extraction,soxhlet extraction and GC-MS analysis equipment.The exhaust emission of the DI single cylinder diesel engine fueled with pure diesel,biodiesel and biodiesel blends of 50%(B50) were measured.The results indicate that the particle-phase PAHs emissions of diesel engine decrease with the increasing of load.The gas-phase PAHs emissions of diesel engine decrease with the increasing of load in the beginning and it turns to going up with further increasing of load.The particle-phase and gas-phase PAHs emissions of biodiesel decrease and mean concentration are lower than that of diesel.The total PAHs emission concentration of biodisesl is 41.1-70.1μg/m3.Total PAHs mean concentration emissions of biodiesel is decreased 33.3% than that of diesel.The mass proportion of three-ring PAHs emissions of those 3 kinds tested fuels is about 44% in the total PAHs.Biodiesel can increase the proportion of three-ring PAHs.Toxic equivalence of PAHs emissions of biodiesel are greatly lower than that of diesel.It is less harmful to human than diesel fuel.更多还原