【摘要】 为了满足低渗透储层水平井改造的需要,开发了一种梳形聚合物与表面活性剂胶束自组装复合压裂液体系。该体系不使用交联剂,不含水不溶物;80℃时,0.3%梳形聚合物CD-1与0.2%表面活性剂组成的自组装压裂液储能模量高达290 Pa,远大于耗能模量,表现出突出的黏弹特性。5 m3/min排量下压裂液的降阻率达到74.05%,具有突出的低摩阻特性。不同配方的自组装压裂液破胶液的表面张力都低于27 m N/m,界面张力低于0.8 m N/m,满足压裂液返排特性的要求。自组装压裂液对储层岩心平均伤害率18.04%,远小于瓜胶压裂液78.75%的水平。室内评价和现场试验施工都表明,自组装压裂液降阻率高,对地层伤害小,增产效果明显,同时证实了利用聚合物与表面活性剂胶束自组装形成结构携砂理论的正确性。该压裂液体系满足特殊结构井压裂改造要求,为特殊低渗透油气藏的开发提供了一种新的方法和手段。更多还原

【Abstract】 To satisfy the needs for low permeability horizontal well fracturing, a compound fracturing fluid has been developed through self-assembly of a comb polymer and surfactant micelles. This fracturing fluid contains no cross-linkers and water insoluble matter. At 80 ℃, the self-assemble fracturing fluid containing 0.3% co 0 mb polymer CD-1 and 0.2% surfactant has storage modulus of 290 Pa, far greater than the loss modulus, showing an obvious viscous-elasticity. At flow rate of 5 m~3/min, the percent reduction in friction achieved with the fracturing fluid is 74.05%, showing an obvious low friction nature. Different self-assembled fracturing fluids all have surface tensions less than 27 m N/m, and interface tensions less than 0.8 m N/m, satisfying the needs for the flow-back of fracturing fluids. Average permeability impairment by these self-assembled fracturing fluids is 18.04%, far less than that of the guar gum fracturing fluids, which is 78.75%. Laboratory evaluation and field application have all indicated that the self-assembled fracturing fluids have high efficiency of friction reduction and low damage to reservoir formation, and higher production rates have been gained using these fracturing fluids. It has also demonstrated the soundness of the theory, which states that through self-assembly of polymers and surfactant micelle, a structure can be developed in the fluid to carry sands. The self-assembled fracturing fluid has satisfied the needs for fracturing wells with special holeprofiles, and provided a new way of developing low permeability reservoirs.更多还原