低渗油藏低频振动辅助表面活性剂复合驱油机理研究

Because of high injection pressure,low flooding efficiency， both low frequency vibration and surfactant can improve water displacement efficiency in low permeability reservoirs at a certain extent. It can be indicated from the earlier laboratory dynamic simulation experiments and pilot field tests that the combination of low frequency vibration and surfactant has significant coordination effect, which can improve the water flooding efficiency significantly. Now, because of rare study on the micro dynamic mechanism of the coposite technology, and not yet well known about dynamic mechanism of oil-water two phase flow in the porous medium under vibration condition and composite mechanism between vibration and surfactant flooding and so on, the application effects in field tests were unstable. In this project, the influence of vibration on oil droplet, single-phase flow and oil-water two-phase flow in low permeable porous medium as well as the mechanism will be studied scientifically,then the influence of vibration parameters on this process will also be analyzed. On this basis,combining with the mechanism of surfactant flooding, The static and dynamic experiments with vibration and surfactant will be conducted by using the Wave Field Simulation Experiment Facility which was developed by ourselves.then,the dynamic composite mechanmism of low frequency vibration and surfactant will be explored. The factors and regular which influence the vibration-surfactant combining flooding effect will be indicated. All above can provide theoretical basis for the optimization design of process program.

由于低渗、特低渗油藏注水压力高，水驱效率低，低频振动和表面活性剂都可在一定程度上提高低渗油藏的水驱油效率。前期室内动态模拟实验和矿场试验表明，低频振动与表活剂有机地结合具有明显的协同效应，可显著提高低渗油藏水驱效率。当前，对该技术复合作用微观动力学机理方面研究较少，对低频振动条件下多孔介质中油水两相渗流动力学机理以及低频波动物理场与表面活性剂驱油之间协同效应机制等基础问题缺乏充分的认识，致使矿场应用效果不稳定。本课题将系统研究低频振动对低渗孔隙介质中单个油滴、单相和油水两相流动影响的动力学机制，分析振动参数对各渗流物理场的影响规律。在此基础上，结合表面活性剂驱油机理，利用自行研制的波动驱油实验装置进行波动-表面活性剂复合驱油静、动态模拟实验，探索低频振动波对表面活性剂驱油协同作用的动力学机制，初步揭示影响振动-表面活性剂复合驱油效果主控因素和相关规律，为工艺方案优化设计提供理论依据。

由于低渗、特低渗油藏注水压力高，水驱效率低，低频振动和表面活性剂都可在一定程度上提高低渗油藏的水驱油效率。前期室内动态模拟实验和矿场试验表明，低频振动与表活剂有机地结合具有明显的协同效应，可显著提高低渗油藏水驱效率。当前，对该技术复合作用微观动力学机理方面研究较少，对低频振动条件下多孔介质中油水两相渗流动力学机理以及低频波动物理场与表面活性剂驱油之间协同效应机制等基础问题缺乏充分的认识，致使矿场应用效果不稳定。本课题通过系统研究低频振动对低渗孔隙介质中单个油滴、单相和油水两相流动影响的动力学机制，分析振动参数对各渗流物理场的影响规律。在此基础上，结合表面活性剂驱油机理，利用自行研制的波动驱油实验装置进行波动-表面活性剂复合驱油静、动态模拟实验，探索低频振动波对表面活性剂驱油协同作用的动力学机制，初步揭示影响振动-表面活性剂复合驱油效果主控因素和相关规律，为工艺方案优化设计提供理论依据。本课题建立了低频谐振波条件下固壁液滴运动、剥离、脱落微观动力学平衡条件，推导了可考虑低频谐振波对流体流动惯性力影响的单管单相流动微观动力学模型，阐明了低频谐振波对流体流速和粘附层的影响机制，揭示了低频谐振波对油水相渗宏观影响规律的内在动力学成因；同时，建立了低频谐振波对表面活性剂静/动态性能影响敏感性实验系统，探讨了低频谐振波参数对表面活性剂洗油性能、乳化性能、乳状液粒径、乳状液稳定性、扩散性能、吸附性能的影响规律，建立了低频谐振波条件下表面活性剂修正两阶段吸附模型，揭示了低频谐振波与表面活性剂驱的内在协同作用机制；进而建立了低频谐振波条件下的辅助方程、油水两相质量守恒方程、表面活性剂输运方程，推导了耦合模型隐式差分数值解，明确了低频谐振波参数对表面活性剂有效作用时间、有效作用距离、出口端浓度、复合驱含水饱和度变化及油藏采出程度的影响敏感性。在低频谐振波辅助条件下，表面活性剂驱油效果得到明显提高，大功率人工低频谐振波辅助表面活性剂复合驱油技术在低渗、特低渗油藏的高效注水开发中具有广阔的应用前景。