热力学模型对石油低压汽液平衡计算的适用性

Predication Accuracy of Vapour-liquid Equilibrium (VLE) Models at Low Pressure for Oils

以 Maxwell- Bonnel图拟合式、对比态 Antoine方程及 Pitzer- Riedel关联式分别求算饱和蒸汽压 p0 ,并用 Roult K值 ( K=p0 / p) ,计算窄馏分 K值。根据实测的中原、孤岛和克拉玛依石油馏分低压 K值 ,考察上述三式 ,结果表明 :对比态 Antoine式预测精度是最好的 ,其温度预测绝对平均偏差为 7.0℃ ,K值预测平均相对偏差为 1 5.6% 。

VLE constants of Zhongyuan, Gudao and Kelamayi oils have been predicted by using three vapour liquid equilibrium (VLE) equations and their accuracy has been checked. The VLE constants are calculated by using Raoult K formula ( K=p 0/p) and the results of the Maxwell Bonnel and the Pitzer Riedel equation are not satisfactory. Reduced Antoine equation has the results of an absolute mean deviation of 7.0℃ for equilibrium temperature and an absolute mean relative deviation of 15.6% for K .