非均质储层中聚合物流度控制对驱油效果影响

Study on Mobility Control of Polymer Flooding in Heterogeneous Reservoir

为了进一步研究非均质储层中聚合物溶液流度控制对低渗透层的作用,采用室内岩心实验模型,应用数值模拟方法,采用有效渗透率分别为1 000×10-3、300×10-3、50×10-3μm2岩心模拟非均质储层条件,注入3种质量浓度的聚合物溶液,通过改变注入3种质量浓度聚合物溶液的方式实现流度控制。注入方案分析了注入聚合物段塞大小,注入顺序对驱油效果的影响。结果表明,在注入聚合物溶液PV数相同的条件下,高、中、低质量浓度段塞比例2∶3∶4时,低渗透层驱油效果最好。改变注入聚合物溶液的段塞大小对高渗透层驱油效果影响不大,对低渗透层驱油效果影响明显。分析认为,合理的流度控制可以有效地提高低渗透层采收率。

In order to further study the effect of mobility control on low permeability layers of heterogeneous reservoir, a numerical simulation model for polymer flooding is established which based on the data of indoor core simulation experiment. This model is used for simulating heterogeneous reservoir with 1 000 × 10-3 μm2 , 300 × 10.3 μm2 and 50 × 10.3 μm2 of the effective permeability respectively. Three kinds of polymer solutions which have different concentrations are injected into core, by changing the way of injection to achieve mobility control. The effect of polymer slug size and sequence on oil displacement is analyzed. The results show that under the same conditions of polymer solution number, slugs-injection schemes achieve better effect with polymer concentration ratio of 2 ： 3 ： 4.The effect of slugs size on high permeability layers is little, while the effect on low permeability layers is obvious. So it can be indicated that measure of mobility control is an effective action to enhance oil recovery.