聚合物驱后二次聚驱可行性及质量浓度优化研究

Study on feasibility of secondary polymer flooding and concentration optimization after polymer flooding

以河南下二门油田为例，采用不同级差的纵向非均质物理模型，进行室内二次聚驱的宏观模拟试验，通过考察剖面改善效果和驱油效果，研究聚合物驱后进行二次聚驱进一步提高采收率的可行性，并对二次聚驱的聚合物质量浓度进行优化。试验结果表明：二次聚驱可进一步提高采收率5％～8％，能够在一定程度上改善油藏的非均质性；在给定试验条件下，二次聚驱聚合物质量浓度应不低于2．2g／L。研究结果为下二门油田提高采收率方案的制定和实施提供了重要的基础参数和理论依据，并为聚驱后进一步提高采收率技术的发展应用提供了新的思路。

Taking Henan Xia＇ermen Oilfield as an example and using vertically heterogeneous physical models with different permeability ratio, laboratory experiments were done to determine the feasibility of secondary polymer flooding and optimize the polymer mass concentration through investigating the profile control and flooding effects. The results show that 5%-8% of improved oil recovery efficiency was obtained, which demonstrates that the reservoir heterogeneity was improved to some extend. The mass concentration of polymer for secondary polymer flooding could not be lower than 2.2 g/L under setting experimental conditions. The results provide not only important basic parameters and theoretical foundation, but also new thinking for development of improved oil recovery technologies after polymer flooding.