【摘要】 在45℃下对超高分(=η=2.59×107)聚合物的高浓度(2.0和2.5 g/L)清水溶液的黏度(7.31 s-1)、抗剪切性、弹性及岩心驱油效果作了比较研究。发表了该聚合物的黏浓曲线。该聚合物的溶液密封老化60天后,黏度保留率随溶液浓度增大(1.0、1.8、2.5 g/L)而增大,分别为87.8%、90.6%、92.9%。与高分聚合物(1.94×107)溶液相比,超高分聚合物溶液经过剪切后黏度降低率较大但保留黏度值较高,代表弹性的第一法向应力差较大(第一法向应力差随剪切速率增大而增大),在两种情况下浓度的影响都与M相似。在渗透率Kg≈1.0μm2的5支非均质岩心(变异系数0.72)和5支均质岩心上,分别注入浓度1.0 g/L的中分聚合物(1.3×107)溶液、浓度2.0和2.5 g/L的高分(1.60×107-1.90×107)和超高分(2.59×107)聚合物溶液,注入量2020(mg/L).PV聚合物在水驱基础上提高采收率的幅度大小排序如下:高浓超高分>高浓高分>常浓中分。图8表2参4。更多还原

【Abstract】 The viscosity(at 7.31 s-1),the shearing resistance,and the oil displacement efficiency of high concentrated(2.0 and 2.5 g/L) fresh water solution of HPAM polymer of ultrahigh molar mass(UHMM) η=2.59×107 are studied comparatively at 45℃.The solution viscosity vz concentration curve is demonstated for this UHMM polymer.The viscosity retention of UHMM polymer solution having been aged in 60 days is increased from 87.8% to 90.6% and to 92.9% when polymer solution concentration increases from 1.0 g/L to 1.8 g/L and to 2.5 g/L,respectively.As compared with a high molar mass(HMM) polymer of η=1.94×107,the percentage reduction in solution viscosity after shearing,the viscosity retention,and the 1st normal stress difference,expressing solution elasticity,for the UHMM polymer are larger with polymer concentration having a similar effect.In laboratory flooding experiments on 5 heterogeneous(coefficient of permeability variation 0.72) and 5 homogeneous artificial cores of Kg≈1.0 μm2,solutions of moderate molar mass(MMM) polymer with η=1.3×107 and of normal concentration 1.0 g/L,of HMM polymer with η=1.60×107—1.90×107 and of UHMM polymer with η=2.59×107 of high concentration 2.0 and 2.5 g/L are injected and the enhancement in oil recovery by polymer flood in amount of 2020(mg/L)·PV after water flood is arranged in order: UHMM polymer in high concentrated solution>HMM polymer in high concentrated solution>MMM polymer in normal concentration polymer.更多还原