低渗透储层纳微米聚合物颗粒分散体系调驱多相渗流理论

Multi-phase flow of aqueous dispersion system of nano/micron-sized polymer particles in low permeability reservoir

采用岩心驱替装置进行渗流规律实验,建立反映纳微米聚合物颗粒水化膨胀、渗流阻力变化、堵塞、相对渗透率变化、颗粒沉淀破碎、残余阻力系数和黏度特性等的渗流特性方程,并建立反映纳微米聚合物颗粒分散体系调驱过程中水、油和纳微米聚合物颗粒之间相互作用与传输,质量的相互转换作用等特点的调驱渗流数学模型。研究结果表明:纳微米聚合物颗粒分散体系单相流动时非达西渗流特征明显,具有启动压力梯度;注入段塞体积、颗粒浓度以及颗粒粒径对驱油效果均有较大的影响,在低渗透高含水油田进行纳微米聚合物颗粒分散体系调驱是可行的,通过优化驱油方案,合理实施,能够取得较好的增油降水效果。

The flow experiments were carried out by the core displacement device. Based on a series of flow experiments,the percolation characteristic equations were set up to represent hydration swelling, percolation resistance, plugging effect,relative permeability, particle precipitation or breakage, residual resistance factor and viscosity of aqueous dispersion system of nano/micron-sized polymer particles. The percolation mathematical models were established to describe interaction, transmission and mass conversion of water, oil and nano/micron-sized polymer particles in the displacement process of aqueous dispersion system of nano/micron-sized polymer particles. The results show that the percolation of aqueous dispersion system of nano/micron-sized polymer particles in low permeability cores has obvious characteristics of non-Darcy flow with a less threshold pressure gradient. The injection slug volume, particle concentration and particle size have effect on oil displacement efficiency. Developing the controllable displacement of nano/micron-sized polymer particles is feasible by optimizing displacement schemes and carrying out reasonable plans for achieving better displacement effect in low permeability reservoir with high water cut.