注入速度对疏水缔合聚合物剪切后恢复性能的影响

针对渤海绥中36-1油田的实际油藏地层条件模拟设计了近井地带模型。研究了注入速度分别为5m³/(m·d)、10m³/(m·d)和20m³/(m·d)时，部分水解聚丙烯酰胺与疏水缔合聚合物2种不同分子结构的聚合物剪切后溶液性能恢复过程。实验结果表明，部分水解聚丙烯酰胺溶液的黏度、阻力系数、残余阻力系数等不能恢复，而疏水缔合溶液经高速剪切后溶液性能可以恢复。在注入速度为5m³/(m·d)时，疏水缔合聚合物在近井地带最终黏度保留率为92.3，阻力系数保留率为43.7，残余阻力系数保留率为81.1，且随着注入速度增大，溶液的黏度、阻力系数、残余阻力系数降低。在注入速度为10m³/(m·d)时，黏度、阻力系数、残余阻力系数保留率分别为70.6、35.2、72.7。注入速度为20m³/(m·d)时，黏度、阻力系数、残余阻力系数保留率分别为55.6、26.3、55.8。利用原子力显微镜观察剪切后疏水缔合聚合物微观形态认为，疏水基团的缔合作用使得原本被高速剪切破坏的溶液网络结构重新生成。

The effect of injection rate on recovery behaviors of hydrophobically associating water-soluble polymers after shearing

A near-wellbore simulation model was designed for the Bohai Suizhong 36-1 Oilfield. The recovery performance process of partially hydrolyzed polyacryamide(HPAM) and hydrophobically associating water-soluble polymers(HAWP) with different molecular structures was studied with the wellbore simulation model at an injection rate of 5m³/(m·d)，10m³/(m·d) and 20m³/(m·d), respectively. The results show that the viscosity, residual resistance factor and resistance factor of HPAM can not be recovered while solution properties of HAWP after high-speed shearing can be restored. With the injection rate of 5m³/(m·d), the final retention rate of the viscosity, resistance factor(RF) and residual resistance factor(RRF) of HAWP is 92.3, 43.7 and 81.1, respectively. The viscosity, RF and RRF of HAWP may decrease with the increase of injection rate. When the injection rate is 10m³/(m·d), the final retention rate of the viscosity, RF and RRF is 70.6, 35.2 and 72.7, respectively, however, when the injection rate increases to 20m³/(m·d), the final retention rate of the viscosity, RF, RRF is 55.6, 26.3 and 55.8, respectively. The microstructure of polymers after shearing was observed with an atomic force microscope. Therefore, the cause of performance recovery for polymer solution after shearing was primarily attributed to the association of hydrophobic groups, which makes the network structure of polymer solution regenerate after high-speed shearing.