稠油油藏聚合物驱剖面反转现象室内实验

Laboratory Experiment of Profile Inversion Regulation in Heavy-Oil Reservoir with Polymer Flooding

为探讨稠油油藏聚合物驱剖面反转规律,建立了与现场实际相似的非均质物理驱替模型,并用聚合物驱替模拟岩心,研究油层渗透率级差、注入浓度、注入时机对聚合物驱剖面反转的影响。实验结果表明:渗透率级差越大,剖面反转出现越早,反转程度越大,说明对于级差较大的稠油油藏用聚合物驱油效果较差;聚合物驱油过程中聚合物浓度越大,剖面反转越早,原油采收率升高,但增长速度变缓,说明在聚合物驱油时需要对聚合物的浓度范围进行界定;聚合物驱油注入时机越早,剖面反转出现越早,应结合生产实际情况选择适当注入时机。该研究成果对聚合物驱提高稠油油藏原油采收率具有指导意义。

A heterogeneous physical displacement model is established to explore profile inversion in heavy-oil reservoir with polymer flooding. This new model is displaced by polymer to study the effects of permeability contrast,injection concentration and injection timing on profile inversion of polymer flooding. Experiment result indicates that high permeability contrast results in early profile inversion and high reversion level. Polymer flooding is relatively inefficient in heavy- oil reservoir with high permeability contrast.High polymer concentration leads to early profile inversion and high oil recovery factor with slow increment in polymer flooding,which reveals an optimum polymer concentration in polymer flooding. Early polymer injection results in early profile inversion and the appropriate injection timing should be optimized according to field production performance. This research could provide certain guidance for enhancing oil recovery in heavy-oil reservoir with polymer flooding.