The density characteristics of CO(2)and alkane mixtures using PC-SAFT EoS
The density characteristics of CO(2)and alkane mixtures using PC-SAFT EoS
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使用 PC-SAFT EoS 计算 CO(2) 和烷烃混合物的密度特性
DOI：
10.1002/ghg.2026
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发表时间：
2020
影响因子：
2.2
通讯作者：
Zhang Yi
中科院分区：
文献类型：
--
作者：
Chi Yuan;Liu Shuyang;Jian Weiwei;Zhao Changzhong;Lv Junchen;Zhang Yi
CO2+原油混合物的密度是影响CO2在油藏中扩散运移的重要参数之一。然而，这将是相当耗时的，以获得全面的密度数据的CO2+烷烃混合物在很宽的温度和压力范围内通过实验方法，因此，一个可靠的模型预测各种CO2+烷烃混合物的密度具有高精度的发展是至关重要的。通过关联正烷烃（除十一烷和十六烷外）的密度数据，优化了微扰链统计缔合流体（PC-SAFT）状态方程（EoS）中的参数m、σ和ε/k。为了进行比较，还使用G‐S PC‐SAFT和HTHP PC‐SAFT EoS来拟合这些正构烷烃的密度，结果表明，在本研究中具有优化参数的PC‐SAFT EoS表现出优越的上级准确性。随后，通过关联含C7-C14烷烃的CO2+烷烃混合物的密度数据，优化了二元相互作用参数kij。并首次建立了优化参数（m，σ，ε/k，kij）与烷烃碳数（n）之间的关联式。这些相关性为PC‐SAFT EoS提供了良好的密度预测通用性和可扩展性。利用这些关联式计算的参数，成功地预测了十六烷和饱和CO2+烷烃混合物的密度，并具有较高的精度。这项工作为CO2+烷烃混合物的热力学性质建模提供了一种新的方法。© 2020化学工业协会和John Wiley & Sons，Ltd.
The density of CO2+ crude oil mixtures is one of the most important parameters influencing CO2diffusion and migration in oil reservoirs. However, it would be quite time consuming to obtain comprehensive density data for CO2+ alkane mixtures over a wide range of temperatures and pressures via experimental methods, therefore the development of a reliable model for predicting the densities of various CO2+ alkane mixtures with high accuracy is crucial. In this paper, the parameters (m,σ, andε/k) in the perturbed‐chain statistical associating fluid theory (PC‐SAFT) Equation of State (EoS) were optimized by correlating density data of pure n‐alkanes from heptane to nonadecane (except undecane and hexadecane). For comparison, the G‐S PC‐SAFT and HTHP PC‐SAFT EoS(s) were also employed to fit the densities of these n‐alkanes, and the results demonstrated that the PC‐SAFT EoS with the optimized parameters in this study exhibited superior accuracy. Subsequently, by correlating density data of CO2+ alkane mixtures containing C7–C14 alkanes, the binary interaction parameterkijwas optimized. Furthermore, for the first time, correlations between the optimized parameters (m,σ,ε/k, andkij) and alkane carbon number (n) were established. These correlations provided PC‐SAFT EoS with a good universality and scalability for density prediction. Using the parameters calculated from these correlations, the densities of hexadecane and saturated CO2+ alkane mixtures containing C10–C20 alkanes were successfully predicted with relatively high accuracy. This work provides a new way for modeling the thermodynamic properties of CO2+ alkane mixtures. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.