表面活性剂体系驱油效果分子动力学模拟研究  

A Molecular Dynamical Simulation Study on Oil Displacement Efficiency of Surfactant systems

作　　者：肖波[1] 程杰成 江波[1] 

机构地区：[1]四川大学化学学院,四川成都610064 [2]中国石油大庆油田公司,黑龙江大庆163453

出　　处：《油田化学》2010年第3期291-294,共4页Oilfield Chemistry

摘　　要：采用分子动力学(MD)方法模拟了十二烷基苯磺酸钠(SDBS)、长链脂肪醇聚氧乙烯醚(AEO)以及它们的复配体水溶液对吸附在岩层表面的模拟油正辛烷的洗脱效果,从分子水平上探讨了表面活性剂与石油烃分子的相互作用过程,定量研究了正辛烷扩散进入含表面活性剂的水相的分子数及扩散速度。综合考虑动力学和热力学因素,提出一种新的评价表面活性剂驱油效果的方法,即以正辛烷向水相的扩散速度与平衡时进入水相的油分子数的乘积来定义驱油系数Fp,通过Fp值与文献报道的界面张力值相比较,发现二者之间有良好的对应关系。用分子动力学(MD)模拟方法计算得到的Fp值,可作为一种有效的、简便快捷的三次采油用表面活性剂驱油性能的表征值。The oil relieving efficiency of some aqueous surfactant systems for the model oil（n-octane） absorbed on rock surface was studied by using a technique of molecular dynamical simulation,in which the interactions between the surfactant and the n-octane molecules were visualized and the number of n-octane molecules entered into the aqueous surfactant phase and their influx rate were determined quantitatively.The surfactants studied were sodium dodecyle benzene sulfonate（SDBS）,long chain fatty alcohol polyoxyethylene ether（AEO）,and their mixture.A characteristic parameter,oil displacement factor,which considered both kinetic and thermodynamic aspects of oil relieving,was suggested and determined as the number of n-octane molecules entered into the surfactant phase in the simulation time duration multiplied by their influx rate.The values of oil displacement factor determined for the three surfactant systems were in good coincidence with their interfacial tension values.The oil displacement factor suggested might serve as an easily and fast determinable effective characteristic parameter of EOR polymers.

关 键 词：表面活性剂 驱油效果 分洗油能力 分子动力学模拟 特征参数 提高原油采收率 计算机模拟 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程] O647.2[理学—物理化学]