Experimental and molecular modeling study of the three-phase behavior of (n-decane + carbon dioxide + water) at reservoir conditions.
Experimental and molecular modeling study of the three-phase behavior of (n-decane + carbon dioxide + water) at reservoir conditions.
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油藏条件下（正癸烷二氧化碳水）三相行为的实验和分子模拟研究。
DOI：
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发表时间：
2011
影响因子：
3.3
通讯作者：
J. Trusler
中科院分区：
文献类型：
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作者：
Esther Forte;A. Galindo;J. Trusler
油与二氧化碳和水的混合物的相行为的知识对于油藏工程是必不可少的，特别是在提高石油采收率和二氧化碳的地质储存过程中。然而，为了全面理解，需要完成对简单系统的研究。在这项工作中，系统（正癸烷+二氧化碳+水）作为一个模型（油+二氧化碳+水）的混合物进行了研究。为了实现这一目标，我们设计了一种新的高压相平衡分析装置，其最高工作温度和压力分别为423 K和45 MPa。该设备依赖于两个共存相的再循环，使用在这项工作中设计的双通道磁操作微型泵，通过气相色谱法进行采样和在线成分分析。该装置已通过与已发表的二元体系（正癸烷+二氧化碳）的等温汽液平衡数据的比较进行了验证。在三相平衡条件下测定了正癸烷+二氧化碳+水体系的新的实验数据。三个共存相的数据已获得五个等温线在323至413 K的温度和压力的两个阶段成为临界点。实验工作是补充在这里与理论上的努力，我们开发的模型，这些分子的框架内的统计关联流体理论的潜力的可变范围（SAFT-VR）。三个二元子系统的相行为计算使用该理论，并在适用的情况下，修改的哈德逊和McCoubrey组合规则被用来处理系统的预测。的三元混合物获得的实验数据进行比较的理论预测。此外，详细分析的三元混合物进行比较的基础上与现有的数据组成的二元子系统。以这种方式，我们分析了当添加第三组分时观察到的对溶解度的影响。
Knowledge of the phase behavior of mixtures of oil with carbon dioxide and water is essential for reservoir engineering, especially in the processes of enhanced oil recovery and geological storage of carbon dioxide. However, for a comprehensive understanding, the study of simpler systems needs to be completed. In this work the system (n-decane + carbon dioxide + water) was studied as a model (oil + carbon dioxide + water) mixture. To accomplish our aim, a new analytical apparatus to measure phase equilibria at high pressure was designed with maximum operating temperature and pressure of 423 K and 45 MPa, respectively. The equipment relies on recirculation of two coexisting phases using a two-channel magnetically operated micropump designed during this work, with sampling and online compositional analysis by gas chromatography. The apparatus has been validated by comparison with published isothermal vapor-liquid equilibrium data for the binary system (n-decane + carbon dioxide). New experimental data have been measured for the system (n-decane + carbon dioxide + water) under conditions of three-phase equilibria. Data for the three coexisting phases have been obtained on five isotherms at temperatures from 323 to 413 K and at pressures up to the point at which two of the phases become critical. The experimental work is complemented here with a theoretical effort in which we developed models for these molecules within the framework of the statistical associating fluid theory for potentials of variable range (SAFT-VR). The phase behavior of the three binary subsystems was calculated using this theory, and where applicable, a modification of the Hudson and McCoubrey combining rules was used to treat the systems predictively. The experimental data obtained for the ternary mixture are compared to the predictions of the theory. Furthermore, a detailed analysis of the ternary mixture is carried out based on comparison with available data for the constituent binary subsystems. In this way, we analyzed the observed effects on the solubility when the third component was added.