Abstract: The polymer-flooding experiment was made by using the three dimensional physical model.The sweep efficiency and the distribution characteristics of the remaining oil in the heterogeneous sandstone oilfields were studied.The results of oil displacement experiments with 4 different kinds of flooding methods after polymer flooding showed that the sweep efficiency of high permeability layers was the biggest,and there was a little potential to further increase the sweep volume and to reduce remaining oil.The binary system or ternary system oil displacement method could be used to further enhance the recovery of remaining oil.The medium or low permeability layers had a low sweep efficiency and higher oil saturation.The profile modification or high viscosity polymer flooding could increase sweep volume,and the ternary mixture flooding could enhance oil displacement efficiency.The above methods should be combined to further enhance oil recovery.

Key words: heterogeneous sandstone, polymer flooding, three dimensional physical model, sweep efficiency, oil displacement efficiency, remaining oil distribution, enhanced oil recovery

摘要： 利用三维大型物理模型进行了聚合物驱油实验,研究了非均质砂岩油田聚合物驱油过程中波及系数变化情况和聚合物驱后剩余油分布特征。对4种不同方法的驱油实验对比研究结果表明,在聚合物驱后,高渗层位的波及系数较大,进一步扩大波及体积而降低剩余油饱和度的潜能较小,可通过二元或三元体系驱方式提高驱油效率来进一步挖潜剩余油;而中、低渗透层的波及系数低,含油饱和度高,可采用调剖或高黏度聚合物驱扩大波及体积与三元复合驱提高驱油效率相结合的方法进一步提高最终采收率。

关键词: 非均质砂岩, 聚合物驱油, 三维物理模型, 波及系数, 驱油效率, 剩余油分布, 提高采收率