鉴于柴油机节能减排的需要,微乳生物柴油是一个重要的发展方向。结合国内外微乳生物柴油的研究,综述了微乳生物柴油的稳定性与理化特性,柴油机燃用微乳生物柴油的动力性、经济性和排放特性,对比分析了柴油机用微乳生物柴油与柴油在性能上的差异及原因。研究表明:微乳生物柴油的滞燃期较长,使得压力上升速率、缸压峰值和瞬时放热率峰值升高;燃用微乳生物柴油的有效热效率大多高于柴油;燃用微乳生物柴油可以显著降低NOx和炭烟排放,CO和HC排放也有一定程度的减少,颗粒物及PM10排放均有所减少。在微乳生物柴油制备方面,添加扩展型羟酸酯类表面活性剂或加入金属催化剂可以提高微乳液的稳定性,减少污染物排放,满足绿色环保的要求。研究还指明,进一步降低微乳生物柴油的黏度,降低制备成本是微乳生物柴油未来的研究方向。
In view of the demands on energy saving and emission reduction for diesel engine, the application of microemulsified biodiesel is an important development trend. The stability and the physical and chemical characteristics of microemulsified biodiesel and the power, economy and emission performance of diesel engine fueled with it were reviewed based on domestic and abroad research. The performance differences of diesel engine fueled with microemulsified biodiesel and diesel were compared and analyzed. The study shows that the ignition delay period of microemulsified biodiesel is long so that the pressure rise rate, cylinder pressure peak and transient heat release increase. The effective thermal efficiency of microemulsified biodiesel is higher than that of diesel in most cases. Microemulsified biodiesel can reduce NOx and soot emissions significantly, reduce CO and HC emissions to a certain degree and reduce particulate and PM10 emissions slightly. As for the preparation of microemulsified biodiesel, the addition of expanded hydroxyl acid ester surfactant or metal catalyst can improve the stability and reduce pollutant emissions so the requirements of environmental protection are met. The study also points out that the further decrease of viscosity and the reduction of preparing cost will be the future research direction.