Peng-Robinson状态方程计算合氢系统汽液平衡——超临界气体的参数处理

Calculations of Vapor-liquid Equilibria of Hydrogen-Containing Systems with Peng-Robinson Equation of State-Modification of Parameters for the Supercritical Gas

本文修正了Peng-Robinson 状态方程,使之适用于氢烃二元系统的汽-液平衡计算.对超临界气体氢引入了新的、随温度而变的a表达式和协体积项b的二元交互作用参数.计算了19个二元系统,结果表明本研究较前人为优.尤其是对氢-重烃(C_6-C_(16)),亦优于Mathias修正的Redlich-Kwong-Soave状态方程和Chao等人最近提出的立方型转子链状态方程(CCOR状态方程).修正后的a表达式除改进了汽液平衡结果,还可准确地推算氢气的P-V-T关系和第二维里系数.本研究推荐的方法可用于实际工程计算.

Peng-Robinson equation of state was modified to represent vapor-liquid equilibria tor hydrogen-hydrocarbon binary systems. A new expression of the temperature dependent parameter for the supercritical gas hydrogen, and binary interaction parameters were introduced to improve description of vapor-liquid equilibria for 19 binary systems. Results show that this work is superior to previous researches, and to Mathias RKS and CCOR equation of state for heavy hydrocarbons, C6 to C16, in particular. Moreover, estimations of p-V-T relation and second virial coefficients of hydrogen from our modification are in good agreement with the experimental data.