使用热场发射扫描电子显微镜拍摄了5种生物柴油和0号柴油在常温常压状态下燃烧产生的碳烟照片,分析了碳烟粒子的形貌及影响形貌和生成量的因素。研究表明,碳烟粒子多呈球状,平均直径在35~75nm之间,粒径分布符合高斯分布,总体排列呈现链状或者块状;碳烟形貌及生成量与火焰温度、燃料的氧含量、芳香烃含量、硫含量以及十六烷值等因素有关,与柴油相比,生物柴油燃烧火焰温度高、含氧量高、芳香烃和硫含量少,十六烷值高,使生物柴油的碳烟粒径普遍较小,整体排列更紧密,粘结程度更强。
This paper is intended to study and analyze bio-diesel-burning soot in terms of factors affecting its particles morphology and amount of soot generation based on the pictures taken from burning bio-diesel oils and common diesel No.0 by using the field emission scanning electron microscope. Results found that the soot particles, most of which were in globular shape, ranged averagely between 35 to 75 nm in diameter with the size distribution according to Gaussian distribution. The soot morphology and formation amount were associated to several parameters such as flame temperature, contents of O2, aromatic hydrocarbon and sulfur in the oils and the cetane number of the oil itself. Compared with the common diesel No.0, the bio-diesel oil generated the soot particles, which, being in smaller sizes tended to more closely and tightly bind together.