关键词: 聚合物溶液, 流变性, 衰竭层, 粘弹性, 残余油, 驱油效率

Abstract: The rheological behaviors of hydrolyzed polyacrylamide (HPAM) solution and xanthan gum solution and their rheological behaviors in porous media were measured experimentally.A calculation model for apparent viscosity of polymer solutions in porous media in the presence of both depleted layer effectiveness and visco-elastic effectiveness was established.The oil displacement experiments with two types of polymers were carried out under the conditions of various concentrations and injecting speeds. The results showed that the increase of apparent viscosity or the decrease of the thickness of depleted layer were resulted from the overlap of polymer molecules,which increased the force parallel to oil water interface and reduced the saturation of residual oil and enhanced the displacement efficiencies of polymers.While increasing concentrations or injecting speeds of HPAM solutions,the displacement efficiencies also increased.The displacement efficiency of xanthan gum solution was low,when its concentration was lower than the overlap concentration.The displacement efficiencies of xanthan gum could keep a higher value,as its concentration was higher than the overlap concentration.The displacement efficiency kept stable,when increasing the injecting speeds of xanthan solutions.

Key words: polymer solution, rheological behavior, depleted layer, visco-elasticity, residual oil, oil displacement efficiency