弱凝胶调驱体系性能评价研究

Evaluation of the performance of weak-gel profile-controlling and flooding system

针对具有储层非均质性强、渗透率低和孔隙结构复杂特点的储层,在注水开发后期,含水率急剧上升,普通的水驱和聚驱方法很难将油驱替出。复合离子型聚合物凝胶有很好的储层适应性,与注入污水配伍性好,成胶时间可控,吸附、滞留能力强,抗冲刷性好。其注入能力强,波及范围大,既可以封堵储层大孔道("调"的作用),又可以驱替储层剩余油("驱"的作用),能够满足调驱体系大剂量注入的要求。本文针对复合离子型凝胶调驱体系进行配方优选并进行性能评价实验,实验结果表明,该调驱体系具有较好的抗盐性、抗剪切性、热稳定性和黏弹性。

For reservoirs with high heterogeneity, low permeability and complex pore structure, the water cut sharply increases in the late-stage development by water injection, and ordinary water flooding and polymer flooding methods are difficult to obtain oil. In contrast, the composite ionic polymer gel has good reservoir adaptability, good compatibility with injected sewage, controllable gelation time, strong adsorption and retention capacity, and good resistance to erosion. Its strong injection ability and wide spread range can not only seal the large pores of the reservoir(namely 'profile-controlling'), but also can drive the remaining oil in the reservoir(namely 'flooding'), and thus can meet the requirements of large-dose injection of the profile-controlling and flooding system. In this paper, formula optimization and performance evaluation were both carried out for the profile-controlling and flooding system based on composite ionic gel. The experimental results show that the system has good salt resistance, shear resistance, thermal stability and viscoelasticity.