为了深入揭示低渗透储层非均质性对聚合物颗粒分散体系驱油效果的影响,采用平板填砂模型和岩芯串、并联组合实验技术,对纳微米聚合物颗粒分散体系进行了非均质驱油实验研究,并分析了纵向、横向非均质性和渗透率级差对驱油效果的影响。平板填砂模型模拟实验结果表明,聚合物颗粒分散体系对改善储层纵向非均质性效果更明显,在纵向非均质模型中提高的采收率比横向非均质模型高9.83%。岩芯组合模拟实验结果表明,随着渗透率级差增加,聚合物颗粒分散体系提高串、并联岩芯组合模型的采收率均逐渐增大,在相近渗透率级差变化情况下,聚合物分散体系提高串联岩芯组合模型的采收率增幅为6.65%,而提高并联岩芯组合模型的采收率增幅为9.48%;渗透率级差越大,高、低渗岩芯的分流量相差越大,聚合物颗粒分散体系调驱后,高渗岩芯的分流量降低,低渗岩芯的分流量增大。
In order to reveal deeply the effects of heterogeneity to oil displacement effect of aqueous dispersion system of nano/micron-sized polymer particles in low permeability reservoir,heterogeneous oil displacement experiments of nano/micron-sized polymer particle were conducted by plane sandpack model and cores series and parallel combination experiment tech-nology. The influences of vertical heterogeneity,lateral heterogeneity and permeability ratio on oil displacement effect were analyzed. The experimental results of plane sandpack models show aqueous dispersion system of nano/micron-sized polymer particles reduces vertical heterogeneity of low permeability reservoir more effectively,with 9.83%higher recovery rate than in the lateral heterogeneous models. The experimental results of core combination models show the recovery rates improved by the aqueous dispersion system of nano/micron-sized polymer particles in cores series and parallel combination models increase gradually with increasing permeability ratio,which have a growth of 6.65%in the core is series ones and a growth of 9.48%in the parallel combination ones. The bigger the permeability ratio is,the greater the difference of fluid productions in low and high permeability cores is. After the aqueous dispersion system of nano/micron-sized polymer particles injected into cores,the fluid productions reduce gradually in high permeability cores and increase by degrees in low permeability cores.