【作者】 孙春柳；

【导师】 丁云宏； 刘先贵；

【作者基本信息】 中国科学院研究生院（渗流流体力学研究所） ， 流体力学， 2010， 博士

【摘要】 论文以实验研究为基础,分析了弱碱(碳酸钠)对三元复合体系的作用规律,并与强碱(氢氧化钠)三元复合体系进行对比。相同因素水平下,弱碱复合体系的界面张力低于强碱复合体系；粘度稳定性好于强碱复合体系；弱碱对体系的流变性和粘弹性影响不大,强碱对体系的和流变性粘弹性影响较大；油水体积比和碱浓度影响体系的乳化能力,相同因素水平下,弱碱复合体系的乳化能力低于强碱复合体系。研究了复合体系中碱、表面活性剂和聚合物在不同矿物上的吸附规律；首次研究了界面张力和乳化对表面活性剂在油水中分配系数的影响；首次研究了两相条件下,弱碱/强碱复合体系中三种化学剂在多孔介质中的传输规律并进行了分析。弱碱体系启动残余油的微观机理是：通过乳化剥蚀,启动细小孔道、孔隙盲端、模型边缘的大部分残余油,油滴以水包油型乳状液的形式被夹带运移,最终被采出。强碱体系还出现了拉丝现象。在相同驱替条件下,弱碱复合驱后残余油量大于强碱复合体系。驱油实验结果表明：碱浓度越大,体系的驱油效率越高。碱浓度一定时,强碱体系的驱油效率高于弱碱体系；提高采收率的幅度是界面张力、粘度、粘弹性和乳化等的综合作用,低界面张力对提高采收率有利,但不是决定因素,乳化是决定提高采收率幅度的关键因素。更多还原

【Abstract】 The effects of weak base (sodium carbonate) on the performance of ASP flooding system were studied through experiments, and then they were compared with the strong base (sodium hydroxide) ASP flooding system.Weak base ASP system compared with strong base ASP system, the interfacial tension of weak base ASP system is lower than that of strong base ASP system under the same level. Apparent viscosity stability of weak base ASP system is better than that of strong base ASP system. The effect of weak base on the rheology and viscoelasticity of ASP system is less than that of strong base. Oil water volume ratio and weak or strong base affects the emulsification ability of ASP flooding system. The emulsification ability of weak base ASP flooding system is weaker than that of strong base ASP flooding system under the same base concentration and oil water volume ratio.For different kinds of minerals, adsorption rules of weak base and strong base, surfactant and polymer in ASP flooding systems were studied. The effects of interfacial tension and emulsification on the partition coefficient of surfactant in oil and water phase were studied for the first time. And transmission rules of weak base or strong base, surfactant and polymer of ASP flooding systems in the porous media under oil and water phase, and some related analysis were carried through.Micromechanism for weak base ASP flooding system starting up residual oil after water flooding was also studied. At first, the residual oil was emulsified by weak base ASP flooding system and was cut into smaller oil droplets which were carried and transported in the form of oil in water emulsion. Finally, they were displaced out. That oil droplets were stretched into lines was also observed in strong base ASP flooding system. Strong base ASP flooding system displaces more residual oil than weak base ASP flooding system.Displacing oil efficiency experiments show that the higher the base concentration is, the higher the displacing oil efficiency is. At a certain base concentration, displacing oil efficiency of strong base ASP flooding system is bigger than that of weak base ASP flooding system. Since the extent of enhanced oil recovery is a result of the comprehensive function of interfacial tension, viscosity, viscoelastcity and emulsification, though low interfacial tension is available for enhanced oil recovery, it is not the key factor for determining oil recovery but emulsification determines the extent of oil recovery.更多还原