生物柴油低温凝固机理与石蜡沉积热力学模型研究

项目名称： 生物柴油低温凝固机理与石蜡沉积热力学模型研究

项目编号： No.51206188

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 工程热物理与能源利用学科

项目作者： 陈五花

作者单位： 中国石油大学（华东）

项目金额： 25万元

中文摘要： 生物柴油低温流动性的研究刚刚起步，集中在低温流动性的影响因素及改进方法方面，对低温下蜡晶的结晶行为研究鲜有报道，生物柴油中蜡晶的析出对其低温流动性的影响至关重要。本项目以脂肪酸甲酯低温下的结晶行为（热力学、晶体形态学和结晶动力学行为）为切入点，对生物柴油低温凝固机理及石蜡沉积的热力学模型进行基础研究。具体内容包括：测量不同原料生物柴油的析蜡点、不同温度下的析蜡量、析出蜡晶组成以及析出蜡晶的分子结构；研究不同原料生物柴油冷却过程中的结晶速率常数、粘度变化及微观蜡晶形态变化；利用分子动力学模拟直接从微观上对生物柴油的低温凝固过程进行研究；建立石蜡沉积的正规溶液理论模型，从理论上预测温度和组成对生物柴油石蜡沉积的影响。本项目旨在揭示生物柴油低温下失去流动性的原因，为有效预防蜡晶的析出，寻找改善生物柴油低温流动性能的方法提供理论依据。

中文关键词： 生物柴油；凝固机理；热力学模型；分形维数；等温胶凝

英文摘要： The study on flow properties of biodiesel at low temperature has just started at the present time. Researches focus on the influencing factors and improved methods for cold flow properties of biodiesel, however, the crystallization behavior of wax at low temperature is little studied which is crucial for the cold flow properties. Based on the crystallization behavior (thermodynamics、crystal morphology and crystallization kinetics)of fatty acid methyl ester at low temperature, the solidification mechanism of biodiesel and thermodynamic modeling of wax precipitation are studied in this work. The main contents of the study are as follows: The wax apperance temperature of biodiesel,the amount and composition as well as crystal structure of wax precipitated from biodiesel at different temperatures are measured. The crystallization rate constant and viscosity as well as wax crystal morphology of biodiesel during cooling process are also investigated. The molecular dynamics simulations are used to study the solidification process of biodiesel from microcosmic view. The regular solution model of wax precipitation is established which can predict the impact of temperature and composition of biodiesel on wax precipitation. The purpose of this project is to reveal the reason for poor fluidity at low temperature, provide

英文关键词： Biodiesel；Solidification mechanism；Thermodynamic modeling；Fractal dimension；Isothermal gelation