Abstract:

Two alpha functions (BM, SRW) and three different mixing rules (MHV2, WS, HG) for the PR and RKSEOS were investigated in the vaporliquid equilibrium calculation of related binary systems for FischerTropsch synthesis oil systemFurthermore, two different equations of states (EOS) of SR-POLAR and PC-SAFT, together with two activity coefficient equations of UNIF-DMD and UNIF-HOC were investigatedThe results showed that various prediction methods had similar deviations for weakly polar systemsHowever, these method had different prediction abilities for other systemsUNIF-DMD, RKS-HG and RKS-MHV2 models gave more accurate prediction for nonassociating strongly polar system, RKS-MHV2 and UNIF-HOC models showed the smallest deviation for associating strongly polar system containing water, UNIF-HOC and SR-POLAR models showed the smallest deviation for associating strongly polar system containing acids, and UNIF-HOC, SR-POLAR models showed the smallest deviation for other associating strongly polar systems, while RKS-MHV2 and RKSHG took the second placePC-SAFT model would bring big deviation for unsymmetrical system when binary parameters were lacking, but would give small deviation for all systems when binary parameters were available.

Key words:

费托合成, 汽液平衡, 状态方程, α函数, 混合规则, 活度系数方程

摘要： 比较了基于不同α函数（BM、SRW）和不同混合规则（MHV2、WS、HG）的PR、RKS状态方程，SR-POLAR和PC-SAFT状态方程，以及UNIF-DMD和UNIF-HOC活度系数方程在费托合成油品体系预测汽液平衡的能力。结果表明：对于弱极性体系，各种计算方法结果接近，偏差均较小；对于非缔合极性体系，UNIF-DMD、RKS-MHV2和RKS-HG方程计算结果比较准确；对于含水缔合极性体系，RKS-MHV2方程和UNIF-HOC方程计算结果比较准确；含酸缔合体系，UNIF-HOC方程和SR-POLAR方程显示了最准确的预测能力；其他缔合极性体系，UNIF-HOC方程和SR-POLAR仍然显示了最高的计算精度，RKS-MHV2和RKS-HG次之；PC-SAFT缺少交互参数时，非均匀体系计算偏差较大。

关键词:

费托合成, 汽液平衡, 状态方程, α函数, 混合规则, 活度系数方程