聚合物驱后提高原油采收率平行管试验研究

为了提供选择聚合物驱后的后续水驱方法的依据．通过平行管流动试验．分高、中、低3种渗透率模拟油藏非均质性条件，研究聚合物驱后压力、相对吸水量、各渗透率层采收率、含水率的变化。试验结果：聚合物驱后直接进行深部调剖．由于聚合物溶液仍占据部分高渗透孔道，黏性较高的深部调剖剂会对中、低渗透率层造成伤害．因此将影响最终的原油采收率；聚合物驱后注入固定剂溶液．交联并固定孔隙中已有的高浓度聚合物溶液．能有效控制这部分高渗透孔道的吸水能力，可以提高后续水驱的波及系数．并为进一步深部调剖奠定良好的基础。聚合物固定技术具有成本低廉、采出程度高以及对地下聚合物溶液利用程度高等优点．是十分有效的聚合物驱后提高原油采收率的方法。图5表4参5

Parallel-column experiments for enhancing oil recovery after polymer flooding

In order to prove the water flooding method after polymer flooding, the variations of the pressure, relative water intake, recovery efficiency of respective layers and water cut are studied in flow experiments of parallel columns simulating the real reservoir heterogeneity with high, medium and low permeability. The results show that, with polymer occupying part of the high permeability channels, direct deep profile control after polymer flooding, with the deep profile control agent of high viscosity, will do harm to the layers of low and medium permeability, then will decrease oil recovery. Injecting polymer-fixing agent after polymer flooding will cross-link and fix the high concentration polymer existing in pores of high permeability, then effectively control the water intake ability of big channels and increase the sweep efficiency of succeeding water flooding, which will make foundation for further deep profile control. Compared with the technology of injecting deep profile control agent after polymer flooding, this polymer-fixing technology is predominant in low cost, high oil recovery and utilizing extent of polymer existing in porous media as an effective treatment for improving oil recovery after polymer flooding.