长链氧化胺黏弹性清洁压裂液及其流变特性

ViscoelasticSurfactantFracturingFluidsBasedonLongChainAmineOxideandTheirRheological Properties

金雷平 卢拥军 邱晓惠 杨江 方波 崔伟香 田萌

JIN Leiping LU Yongjun QIU Xiaohui YANG Jiang FANG Bo CUI WeixiangTIAN Meng

本文获得了由长链氧化胺表面活性剂LAO与反离子盐复配形成的清洁胶束压裂液体系，并进一步研究了该体系流变性能、耐温性能及其相关影响因素。结果表明，LAO清洁压裂液最优组成为2%LAO+3% 水杨酸钠（NaSal），该体系的耐温极限为120℃。该体系在110℃、170 s-1下剪切1 h 后，体系黏度可保持在30mPa·s 以上。同时，该体系具有良好的携砂性能和明显的黏弹性、触变性和剪切变稀特性。破胶实验表明，在压裂液与原油体积比不大于40:1 时，原油可使该体系顺利破胶，破胶液黏度小于3 mPa·s。图5 表2 参15

A clean micelle fracturing fluids based on long chain amine oxide surfactant and counter-ion salts was obtained, and the rheological properties, thermal stability and related factors of the system were studied. The results showed that, the optimal formulation was 2% LAO + 3% NaSal, and the temperature resistance limit value of the system was of 120℃. The viscosity of the optimal system was kept above30mPa·s after sheared for 1 hour at the shear rate of170 s-1 at the temperature of 110℃. The rheological results showed that the 2%LAO +3%NaSal fracturing fluids was characteristic of significant viscoelastic, thixotropic and shear thinning properties, and possessed excellent proppant-suspension property. Gel breaking experiments proved that when the volume ratio of the fracturing fluidings to the crude oil was lower than40:1, the fracturing fluids could be broken completely after mixed with the crude oil, and the viscosity of the broken fluids was less than 3 mPa·s.