复合驱油技术应用中几项要素的优化研究

OPTIMIZE STUDY ON SEVERAL ELEMENTS IN THE APPLICATION OF CHEMICAL FLOODING TECHNOLOGY

新的毛管数理论认为，当毛管数增大到一极限毛管数后，残余油达到一相对低值，毛管数进一步增大，残余油不再减少，直至毛管数增大到另一极限毛管数后，出现驱动状况转化，残余油出现复杂变化。以该理论为基础，详细介绍了通过新的毛管数实验曲线优化驱油要素的方法，即必须将驱油过程严格控制在“第一类”驱动状况下；必须从三维非均质油藏出发，同时考虑复合驱的驱替特征；应从优化渗流速度出发优化注采井距和注液速度，进而优化驱油体系黏度和界面张力。研究成果进一步推动了新毛管数理论的发展，为复合驱技术的实际应用提出了指导意见。

New capillary number theory indicates that there are two kinds of displacement processes. The first kind is that the residual oil will reach a relatively lower value when the capillary number increased to one limiting value, and it will no longer decrease even through the capillary number increased further. The second kind is that until the capillary number reached to another limiting value, the driving status would transform and residual oil would be- come complex. Based on such theory, this paper concretely presents the method of optimizing displacement ele- ments by new capillary number lab curve. That means, the displacement process must be controlled under the first kind of displacement process, and the three dimensional heterogeneous reservoir must be considered, as well as the displacement characteristic of ASP flooding （ Alkaline-Surfactant-Polymer Flooding}. The producer-injector spacing and injection velocity should be optimized based on the optimization of seepage velocity, and further, optimize the viscosity and interracial tension of displacement agent. This research promotes the development of new capillary number theory, and provides guidance to the practical application of ASP technology.