文献类型：期刊文献

中文题名：热力学模型预测低温下柴油中正构烷烃的析出

英文题名：Prediction of the settling of n-alkane in diesel by thermodynamic model

作者：吕涯[1];陈淑芬[1]

机构：[1]华东理工大学石油加工研究所,上海200237

年份：2007

卷号：26

期号：12

起止页码：1743

中文期刊名：化工进展

外文期刊名：Chemical Industry and Engineering Progress

收录：CSTPCD;;Scopus;北大核心:【北大核心2004】；CSCD:【CSCD2011_2012】；

语种：中文

中文关键词：柴油;正构烷烃;低温流动性能;热力学模型

外文关键词：diesel oil; n-alkane; low-temperature flow performance; thermodynamic model

摘要：根据柴油的组成复杂的特点,采用状态方程描述液相,溶液理论描述固相,对低温下柴油液固两相平衡的液相组成和固相组成进行了计算。并将正构烷烃以外的其它组分作为一个虚拟组分,简化了组分极其复杂的柴油。应用建立的模型计算了两种柴油的析蜡温度,并与柴油的实测浊点进行了比较,结果表明选择的热力学模型适用于低温下柴油液固两相平衡的计算。根据计算得到的液相组成和固相组成,分析了低温下柴油中各正构烷烃析出的趋势,结果表明碳数越大的正构烷烃虽析出趋势大,但由于在整个正构烷烃中所占比例较小,故其在固相中的比例依然较小;碳数为20左右的偶数正构烷烃,最容易析出。随着温度的降低,析出固体中正构烷烃的平均碳数变小。并根据计算结果较好地解释了低温时析出固相中始终存在非正构烷烃组分的实验现象。
Based on the characteristics of complicated composition in diesel, equation of state was applied to the description of the liquid phase, and regular solution theory was applied to the description of the solid phase for the sake of calculation of the compositions of the phases of liquid and solid in equilibrium. For the first time, non-n-alkane composition was regarded as a pseudo-component to simplify calculation. The thermodynamic model can successfully predict the temperature of wax appearance, which is close to the cloud point. The trend that every n-alkane in diesel was settled was studied by means of calculated compositions of solid phase and solid phase. The proportion of heavy n-alkane in solid was still small despite the stronger settling trend of heavy n-alkanes than light n-alkanes, because the proportion of heavy n-alkane in the original diesel was small, n-Eicosene, n-octadecane and n-docosane were most easily precipitated in diesel. The average carbon number of n-alkane in settled solid became less with increasing temperature. The phenomena that the settled waxy crystals entrapped significant amounts of liquid could be explained by calculated results obtained from thermodynamic model.