石油馏分临界性质ERD预测方法的考察与修正

INVESTIGATION AND MODIFICATION OF ERD METHOD FOR PREDICTION OF THE CRITICAL PROPERTIES OF PETROLEUM FRACTIONS

用实测出的59组国产石油馏分临界温度和临界压力数据考察了用化学组成与临界性质相关联预测石油馏分临界性质的ERD(Erbar Riazi Daubert)方法,发现其平均相对偏差较小,临界温度的相对偏差为1.27％,临界压力为5.90％.但这种方法的使用范围很窄,可计算数据组数只占44.1％.为保持ERD方法的优点,解决使用范围窄的问题,本文提出了ESC(Erbar Structural Com-position)方法,此方法先用n-d-m法求出石油馏分结构族组成,再求出结构原子团量百分率,可计算出石油馏分的临界温度和临界压力,其计算准确性与ERD法相近。计算出的国产石油馏分临界温度的平均相对偏差为1.19％,临界压力的相对偏差为7.62 ％,使用范围大大扩展,计算数据组数提高到94.9％,在实际应用中ESC法可代替ERD法。

ERD method for predicting the critical properties of virginpetroleum fractions with correlation bet ween chemical composition and critical properties was examined by using 59 sets of experimental data of critical temperature (Tc) and critical pressure (Pc) of Chinese petroleum fractions.It was found that the average relative errors are relatively small,1.27% for Tc and 5.90% for Pc But the application of ERD method is limited.A new method-ESC (Erbar-S true lural-Composition) is presented in this paper.Molecular structure group composition of petroleum fractions was determined on first step with n-d-m method and the fraction of atomic weight of the structure group was predicted on the second step.Then Tc and Pc can be calculated.The accuracy of calculation is the same as that with ERD method.The application is wider than the former and the sets of data calculated raised to 94.9%.