Abstract: The method for correlating the parameters of Peng-Robinson equation of state has been improved. As compared with the original Peng-Robinson equation and Soave-Redlich-Kwong equation of state, the modified Peng-Robinson model significantly improves the predictions of saturated vapor pressure and liquid density of heavy hydrocarbons(C7+), however, only minor improvement in saturated vapor density prediction if observed. For light components(C7-), theprediction of saturated vapor pressure and vapor density by the modified Peng-Robinson model is as good as Soave-Redlich-Kwong and Peng-Robinson equations of state. However, the description of the saturated liquid density is far superior. The modified Peng-Robenson model is used to predict the phase behavior fo gas condensates (dew point pressure, constant mass expansion and constant volume depletion processes), and better results are obtained.

摘要： 针对含重质烃的多元混合物提出了PR模型参数新的关联方法.对多于7个碳的重烃,其状态方程参数a和b改为通过可由实测数据确定的T_B、(?)和T计算,避免了由不同经验关联式计算的临界参数T_c、P_c和(?)值不一致的缺点.作者将经上述改进的PR模型应用于凝析气相态行为的模拟计算(露点压力、恒质量膨胀和恒容衰竭等过程)取得了较满意的结果.