驱油用聚合物溶液弹性和黏性定量表征实验研究

Experimental research on quantitative characterizations of elasticity and viscosity of polymer solution used to displace crude oil

利用动态实验和蠕变回复实验,研究了不同质量浓度聚合物溶液的黏弹性,计算了聚合物溶液中弹性部分和黏性部分所占的比例,给出了高浓度聚合物溶液体系的质量浓度界限。研究表明:在低外力作用条件下,聚合物溶液中黏性部分所占比例随溶液质量浓度的增加而减小,当质量浓度达到1 500mg/L时,随溶液质量浓度的增加,溶液中黏性部分和弹性部分所占比例基本不变;在低剪切速率(0.062 8s-1)条件下,聚合物溶液中黏性部分所占比例大于弹性部分,黏性部分和弹性部分所占比例分别为60%和40%;在地层剪切速率(6.283s-1)条件下,弹性部分所占比例大于75%,随溶液质量浓度增加,弹性部分所占比例增加,但增加幅度逐渐变小。

Through dynamic and creep-recovery experiments,the viscoelasticity of polymer solutions with different mass concentrations is studied,the proportions of elastic part and viscous part in the polymer solution are calculated and the limit of mass concentration called high concentration polymer solution is given.It is indicated that the viscous part of the polymer solution decreases with the increase in mass concentration under the condition of low external force.The proportions of viscous part and elastic part in the polymer solution are constant when the mass concentration is no less than 1500mg/L.Under low shear rate（0.062 8 s-1） condition,the proportion of viscous part in the polymer solution is greater than that of elastic part and the proportions of viscous part and elastic part are 60% and 40% respectively;but under the oil reservoir shear rate（6.283 s-1） condition,the proportion of elastic part is greater than 75%,and the elastic part increases with the increase in mass concentrations but the increment becomes smaller.