硅氧烷增稠CO_2压裂液高压流变性  

Experimental study on rheological properties of siloxane thickened CO_2 under high pressure

作　　者：李宾飞[1] 柏浩 李强[1] 左家强[2] 李爱山[2] 李兆敏[1] 王彦玲[1] LI Binfei;BAI Hao;LI Qiang;ZUO Jiaqiang;LI Aishan;LI Zhaomin;WANG Yanling(School of Petroleum Engineering in China University of Petroleum(East China),Qingdao 266580,China;Research Institute of Petroleum Engineering Technology,Shengli Oilfield Branch,SINOPEC,Dongying 257000,China)

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580 [2]中国石化胜利油田分公司石油工程技术研究院,山东东营257000

出　　处：《中国石油大学学报（自然科学版）》2018年第6期114-120,共7页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家自然科学基金项目(51574264);国家科技重大专项(2017ZX05072);山东省自然科学基金项目(ZR2015EL015)

摘　　要：压裂过程中CO_2压裂液的相态和流变特性复杂多变,CO_2压裂液的高压流变性是压裂设计的基础。制备一种硅氧烷类增稠剂,测试其增稠性能,并通过改变增稠剂质量分数、温度、压力研究增稠后的CO_2压裂液在毛细管内流动的流变特性。结果表明:8～16 MPa条件下,硅氧烷增稠CO_2压裂液表现为典型的幂律流体特性;温度和压力对硅氧烷增稠的CO_2流变性影响显著,随着温度升高,硅氧烷增稠CO_2的表观黏度降低,稠度系数与流变指数均减小,在30～40℃,CO_2由液态变为超临界状态,增稠CO_2的表观黏度大幅度下降;随着压力升高,硅氧烷增稠CO_2表观黏度升高,稠度系数增大,流变指数减小,CO_2压裂液的非牛顿性增强,压力由8 MPa升高至16 MPa,硅氧烷增稠CO_2的表观黏度增大62%。The phase state and rheological properties of CO2 as a fracturing fluid during fracturing are complex,and its viscosity is fundamental for the process design.In this study,siloxane was tested as a thickener of CO2,and its thickening behavior was investigated at high pressure.The rheological property of the thickened CO2 was measured using a capillary method,in which the effects of thickener mass fraction,temperature and pressure on the viscosity of CO2 were investigated.The experimental results show that the thickened CO2can be characterized as a typical power-law fluid under pressure of 8-16 MPa,and its viscosity are influenced significantly by the variation of temperature and pressure.With increasing temperature,the apparent viscosity of the thickened CO2,the consistency coefficient and the flow index decrease.In the temperature range of 30-40℃,CO2 changes from liquid to supercritical state,and its apparent viscosity decreases dramatically.As pressure increases,the apparent viscosity of the thickened CO2as well as the consistency coefficient increase,while the flow index decreases,and the non-Newtonian feature of the thickened CO2 is enhanced.The apparent viscosity of the thickened CO2 can be increased by 62%when pressure increases from 8 MPa to 16 MPa.

关 键 词：CO2压裂液 高压流变性 硅氧烷增稠剂 流变参数 

分 类 号：TE311[石油与天然气工程—油气田开发工程]