孔隙介质中滞留聚合物粘弹性的测定方法研究

A METHOD OF MEASURING VISCOELASTIC PROPERTIES OF RETAINED POLYMER IN POROUS MEDIA

本文为关于孔隙介质中滞留聚合物粘弹性研究的第四篇论文[1-3]。基于HPAM和xanthan gum分子结构柔性的对比,从理论上证明了柔性滞留分子的粘弹回复使孔喉的有效流动面积呈指数减小,故流量也呈指数衰减。本文提出了一个利用孔隙介质测定聚合物松驰时间的新方法,在岩心流动试验的基础上,计算出描述粘弹性的另一种参数——德博拉数(Deborah number)。岩心流动试验证明,用降压法测定滞留分子的粘弹性时[1],HPAM显示了良好的粘弹性,xanthan gum则基本不显示粘弹性。当用稳压法测示时,HPAM的粘弹性无法测出,证明文献[1]提出的降压法是测定粘弹性的一种行之有效的方法。岩心试验中还研究了岩心渗透率和溶液含盐量对粘弹流动的影响。

This is the fourth paper studying the viscoelaticity of retained polymer molecules in porous media, (1) (2) (3) A comparison of molecular flexibility is made between HPAM and Xathan Gum. It has been shown theoretically that the viscoelastic recovery of the flexible retained molecules causes the effective flowing area of throat to decrease exponentially, and thus causes the flow rate to decrease in the same manner. Based on this, a new method has been developed for measuring the relaxation time of retained polymer molecules in porous media. The effect of core permeability and solution salinity on viscoelastic flow has also been studied.