立方扰动硬链状态方程G^E混合规则及其应用

The Development and Application of G^E Mixing Rule for CSPHC Equation of State

扩展了立方扰动硬链(CSPHC)状态方程在天然气工业中通常遇到物质的纯组分参数, 并建立了纯组分参数的普遍化关联式; 将过量Gibbs自由能混合规则引入CSPHC状态方程, 以应用于高度非对称体系与极性体系相平衡性质计算。结合MPHC活度系数模型及Wilson 活度系数模型, 对13组二元体系的汽液平衡性质获得较满意的结果。

The three pure substance parameters of oil and gas compounds used in the Cubic Simplified Perturbed Hard-Chain (CSPHC) equation of state were generalized. Using this developed CSPHC equation, the absolute average deviations of the calculated vapor pressure and saturated liquid density of 36 pure substances were 1.47% and 3.13%, respectively. The excess Gibbs free energy mixing rule was introduced to CSPHC equation of state to describe the vapor-liquid equilibria at high temperature and pressure including supercritical condition. Good results were obtained for high non-symmetrical mixtures when combined with either MPHC activity coefficient model or Wilson activity coefficient model. The comparison of the results indicated that the new mixing rule was superior over the original CSPHC and SRK equations of state.