Wei Xiong , Lie-Hui Zhang , Yu-Long Zhao , Shao-Mu Wen , Li-Li Liu , Zheng-Lin Cao , Yong-Chao Wang , Shan-Gui Luo , Xian-Yu Jiang
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引用次数: 0
Abstract
Accurate derivatives are required for simulating large-scale carbon dioxide (CO2) geological storage using the Cubic-Plus-Association equation of state (CPA EoS). However, due to the mathematical implicitness of cross-association, calculating the correct derivatives of site fractions for cross-association mixtures is extremely difficult and computationally demanding. A general explicit formulation of cross-association for different bonding types is presented. The non-bonded fraction of cross-associating molecules is obtained from the non-bonded fraction of self-associating molecules without cross-association. This approach eliminates the circular iterative process and improves computational efficiency. The overall CPU time decreases by 70 % for flash calculations and compositional simulations. The modeling capability of CPA is extended to H2O-CO2-H2S-N2-O2-Ar-SO2-CH4-C2H6-C3H8 mixtures. Results indicate that CPA can accurately predict the phase behavior of binary CO2 capture, utilization, and storage (CCUS) mixtures. This study provides a modified CPA EoS, applicable to most of the currently treated CCUS fluids, and discusses its strengths and limitations.
期刊介绍:
The Journal of Supercritical Fluids is an international journal devoted to the fundamental and applied aspects of supercritical fluids and processes. Its aim is to provide a focused platform for academic and industrial researchers to report their findings and to have ready access to the advances in this rapidly growing field. Its coverage is multidisciplinary and includes both basic and applied topics.
Thermodynamics and phase equilibria, reaction kinetics and rate processes, thermal and transport properties, and all topics related to processing such as separations (extraction, fractionation, purification, chromatography) nucleation and impregnation are within the scope. Accounts of specific engineering applications such as those encountered in food, fuel, natural products, minerals, pharmaceuticals and polymer industries are included. Topics related to high pressure equipment design, analytical techniques, sensors, and process control methodologies are also within the scope of the journal.