聚合物溶液在孔隙介质中的蠕变回复和驱油效率

实验室进行了三种不同分子量聚合物溶液在多孔介质中的蠕变回复实验,多孔介质采用的是三种不同结构的微观模型,即:毛细管模型、网格模型和天然模型。通过对模型实验数据的拟合,确定了聚合物溶液的松弛时间,并根据松弛时间大小和流量变化率,评价了不同分子量聚合物溶液的粘弹性行为;还采用人造岩芯研究了聚合物溶液在多孔介质中的蠕变回复1]与驱油效率的关系。结果表明,聚合物分子量越大,松弛时间越长,且蠕变回复过程中流量变化率与聚合物分子量有关,同时,通过聚合物溶液的蠕变回复可以提高驱油效率。

EFFECT OF CREEPING REVERSION OF POLYMER SOLUTION IN POROUS MEDIUM ON THE DISPLACEMENT EFFICIENCY

The creeping reversion experiments of 3 kinds of polymer solutions with different molecular weight were conducted in porous media. The porous media are 3 kinds of micro-model with different structures. They are capillary model, grid model and natural model. The relaxation time was obtained by matching the experimental data. Viscoelastic behaviors of polymer solutions with different molecular weight were evaluated by combining the relaxation time and flow rate variation ratio. The effect of creeping reversion on the oil displacement efficiency was laboratory investigated in artificial cores. Experimental results show that the relaxation time increase with molecular weight, and the flow rate variation ratio affected by the molecular weight. The creeping reversion property can be used to improve oil displacement efficiency.