新型清洁压裂液的室内合成及性能研究

Preparation and capacity testing of a new type clear fracturing fluid

合成了烷基酰胺季铵盐类阳离子粘弹性表面活性剂(Viscoelastic Surfactant,简称VES)EA-22,采用控制应变速率流变仪测定了50℃时3%EA-22+2%KCl体系的储能模量和耗能模量,证实了其存在粘弹性。研究了EA-22作为清洁压裂液增稠剂的流变性能。实验结果表明,EA-22的合成方法具有反应条件缓和、产率较高、副反应少的特点,3%EA-22+2%KCl体系在80℃,105 s-1条件下表观粘度达到86 mPa.s,该体系能够满足悬砂性的要求;体系通过盐水饱和的低渗透岩心时滤失速度较低,破胶简单彻底,残渣少,破胶液粘度低,容易返排。

Viscoelastic surfactant （VES） fracturing fluid of EA-22 which is the type of cationic surfactant of alkylamido quaternary ammonium salt was prepared, The viscoelasticity of the solution of 3 % EA-22 ＋ 2 % KCI was confirmed at 50℃ by means of rheometrics pressure rheometer. The rheology properties of EA-22 as thickness agent of clear fracturing fluid were investigated. The results show that the synthetic method of EA-22 has several characters including mild condition of chemical reaction, comparatively high yield of product and seldom side reaction. The apparent viscosity of 3 % EA-22 ＋ 2 % KCl reaches 86 mPa＇s under the condition of 80 12 and shear rate of 105 s^-1, which can meet the needs of solid-suspend behavior. The leak off rate of this fluid through a salt-saturated core is relatively low and the breaking of EA-22 is simple, and the residue and viscosity of the system after breaking are at a low level, easy to flowback.