近井地带剪切作用对驱油用聚合物溶液渗流特性的影响

在前人的工作基础上设计了一个近井地带剪切模拟装置，选用两种较为典型的聚丙烯酰胺类聚合物——部分水解聚丙烯酰胺(HPAM)和疏水缔合聚丙烯酰胺(HAPAM)进行室内实验，研究两种聚合物溶液经剪切后的渗流特性。实验结果表明：随着吸水强度的增加，两种浓度为1750 mg/L的聚合物溶液的黏度和黏度保留率快速下降。由于自身的疏水缔合作用，HAPAM溶液剪切后具有高于HPAM溶液的黏度及黏度保留率。在吸水强度10 m³/(m·d)和20 m³/(m·d)条件下剪切两种聚合物溶液，经剪切后的HAPAM溶液的阻力系数和残余阻力系数远大于HPAM溶液的，HAPAM溶液的阻力系数损失率小于HPAM溶液，而残余阻力系数损失率大于HPAM溶液。经剪切后的HAPAM溶液具有更高的驱油效率，剪切后HAPAM的溶液原油采收率损失略高于HPAM溶液的。

Effects of Near Wellbore Shearing on the Seepage Characteristics of Flooding Polymer Solutions

A near wellbore shear simulation device was designed on the basis of previous work. And two typical polyacrylamide polymer, partially hydrolyzed polyacrylamide (HPAM) and hydrophobically associating polyacrylamide (HAPAM) were selected in the laboratory. The viscosity and viscosity retention rate, the mobility control capability and the oil displacement efficiency of two polymer solutions after shearing were investigated. The experimental results showed that, with the increase of intake capacity, the viscosity and viscosity retention rate of two polymer solutions at the concentration of 1750 mg/L decreased rapidly. Morever, the viscosity and viscosity retention rate of HAPAM solution after sheared, was higher than that of HPAM solution because of its hydrophobic interaction. When two polymer solutions were sheared at the intake capacity of 10 m³/(m·d) and 20 m³/(m·d), respectively, the resistance factor and residual resistance factor of HAPAM solution were much larger than that of HPAM solution; the resistance factor loss of the HAPAM solution was less than that of HPAM solution and the residual resistance factor loss was higher than that of HPAM solution. HAPAM solution after sheared had higher oil displacement efficiency than that of HPAM solution. While, the loss of oil recovery rate of HAPAM solution is slightly higher than that of HPAM solution.