基于刺激响应策略的可控滑溜水研究

Study on Controllable Slick Water Based on Stimulus Response Strategy

在一些地质条件复杂、低孔低渗、地层压力系数低的区域,存在一些较为严峻的问题,如气藏储层发育的微纳米级孔隙、喉道窄小、排驱压力高、连通性差等。这些问题将导致水锁损害和压裂返排液返排更难。针对这些问题,将刺激响应的表面活性剂引入到疏水缔合聚合物的水溶液系统中,从而赋予了滑溜水体系黏度的可控性,体系最高减阻率可以达到78.1%。在调控下,液体返排难度大大降低,地层伤害也进一步降低。动态光散射实验可以证明,表面活性剂分子可以在不同pH值条件下组装成为不同的结构,疏水缔合聚合物可以和这些结构相互作用,从而实现滑溜水黏度的调节。该滑溜水体系有着良好的减阻性能和防膨能力。

In some areas with complicated geological conditions,low porosity,low permeability and low formation pressures,tough problems such as gas reservoirs developed with micron and nanometer sized pores,narrow pore throats,high displacement pressures and poor connectivity etc.are often encountered,which inevitably result in serious damage to water block ability and more difficulties in flowing back fracturing fluids.To solve these problems,stimulus response surfactants were introduced into the water solution of hydrophobic associating polymers to render slick water controllable viscosity.The friction of the slick water formulated can be reduced by 78.1%.The difficulties of flowing back the slick water were greatly mitigated through regulation and control,and formation damage was further reduced.Dynamic light scattering experiment was used to prove that the molecules of the surfactants can be assembled into different structures at different pH values.The hydrophobic associating polymers can interact with these structures to realize the viscosity control of the slick water.The slick water system formulated has good friction reducing property and swelling inhibition ability.