摘要
针对工业上汽液平衡数据测定误差较大的现象,引入关于液相摩尔分数的三次多项式对Wilson,NRTL活度系数模型进行修正。对绝压20 Pa的中真空下乙二醇+丙三醇与1,2-丙二醇+乙二醇2个二组元物系的汽液平衡数据进行实验测定,所得数据通过Herington热力学一致性检验。借助MATLAB工具箱中的非线性最小二乘法对实验数据进行回归拟合得到新的Wilson,NRTL方程模型参数,经过实验验证,修正多项式的拟合值与实验值相对偏差均低于1%。该方法可以为同类的中高真空精馏提供计算基础及参考数据。
Focusing on the big error existing in the industrial measuring of vapor-liquid equilibrium（VLE） data, a cubic polynomial regarding the molar composition of the liquid phase was proposed to correct the activity coefficient models of Wilson and NRTL. VLE data of two binary mixtures （ ethylene glycol ＋ glycerol and 1,2-propylene glycol ＋ ethylene glycol） measured at 20 Pa satisfy the thermodynamic consistency by Herington method. The experimental data were regressed and correlated by nonlinear least square method of Matlab optimization toolbox. It is verified that the relative deviations between calculated and experimental data are smaller than 1%. This method can provide calculation basis and reference for medium vacuum distillation.
出处
《化学工程》
CAS
CSCD
北大核心
2012年第8期57-60,73,共5页
Chemical Engineering(China)
关键词
中真空
汽液平衡
活度系数拟合
最小二乘法
medium vacuum
vapor liquid equilibrium （VLE）
activity coefficient correlation
nonlinear leastsquare method
