了解CO2-卤水体系的界面张力和黏度对于CO2地质储存研究及CO2驱油提高采收率研究有着重要价值，但是当前仍然缺乏能够准确计算CO2-H2O-NaCl及CO2-卤水体系在宽广的温度压力范围内的界面张力和黏度的模型。本项目计划将申请人已建立的计算中低温CO2-H2O-NaCl-CaCl2体系相平衡和PVTx的SAFT-LJ状态方程扩展到CO2-卤水（含Na+、K+、Ca2+、Mg2+、Cl-、SO42-等）体系，然后结合密度梯度理论处理离子对CO2/H2O界面张力的影响，结合摩擦理论和自由体积理论考虑离子和溶解的CO2对水溶液黏度的影响，建立能够准确计算在273-473 K，0-1000 bar的温度压力范围内CO2/NaCl水溶液界面张力、CO2/卤水界面张力及溶解CO2的NaCl水溶液和卤水黏度的理论模型。在此基础上开发能应用于卤水层CO2储存研究的界面张力和黏度计算程序。

Understanding of the interfacial tension and viscosity of the CO2-brine system is important for the study of CO2 geological storage and the study of CO2-injected enhanced oil recovery. However, there is no model allowing the accurate calculation of interfacial tensions and viscosities of the CO2-H2O-NaCl system and CO2-brine system over a wide P-T range. This project will try to develop an united model for calculations of VLE, PVTx properties, interfacial tensions and viscosities of the CO2-brine (containing Na+、K+、Ca2+、Mg2+、Cl-、SO42-) system from advanced theories for equation of state, interfacial properties and viscosity. Methods for construction of the new model include: (1) extension of the SAFT-LJ EOS developed by the proposer for the CO2-H2O-NaCl-CaCl2 system to the CO2-brine system, (2) coupling the extended SAFT-LJ EOS with density gradient theory to investigate the influence of dissolved ions on the interfacial tension of CO2/H2O, (3) coupling the extended SAFT-LJ EOS with the free volume theory and the friction theory to investigate the effect of dissolved ions and CO2 on the viscosity of H2O. The new model covers the P-T range from 273 473 K, and from 0 to 1000 bar. Based on the new model, this study will also develop a computer program which allows the calculation of the CO2 solubility, density, interfacial tension as well as viscosity of the CO2-brine system and is suitable for the study of CO2 storage in deep saline aquifers.