粘弹性胶束压裂液的形成与流变性质  

Formation and Rheologic Behavior of Viscoelastic Micelle Fracturing Fluids

作　　者：卢拥军[1] 方波[1] 房鼎业[1] 林英姬[2] 王海楼 强会彬 

机构地区：[1]华东理工大学化工学院,上海200237 [2]中国石油勘探开发研究院廊坊分院,河北廊坊065007 [3]中国石油吉林石油集团公司井下作业工程公司,吉林松原138002

出　　处：《油田化学》2003年第4期327-330,共4页Oilfield Chemistry

基　　金：国家973资助项目(编号2001CB209107);国家自然科学基金资助项目(编号20276016)。

摘　　要：由C16、C18烷基三甲基季铵盐和助剂配制了压裂用表面活性剂VES 60。考察了VES 60/水及其他体系形成胶束凝胶的能力。得到了一种蠕虫状胶束和一种片状胶束的环境扫描电镜照片。测定了体积分数(下同)为5%的CTAC与NaSal、NaSal+KNO3水溶液形成的胶束凝胶的粘度(70℃)随剪切速率的变化,讨论了两种盐之间的协同作用。在不同温度(10～40℃)和10s-1下,4%VES 60水溶液形成胶束的动力学包括三个阶段:链分散,低粘度;链缔合,粘度快速增大;链动态平衡,粘度基本稳定。在170s-1下4%VES 60的胶束溶液的粘度随温度升高而下降,在50～80℃区间下降幅度很小,粘度约在60mPa·s上下,在80℃以上急剧降低。20℃时4%VES 60胶束溶液的流变性符合H B模型,k′=8.664Pa·sn′,n′=0.2678,τy=5.4Pa。随表面活性剂体积分数增大(2.0%～5.0%),30℃时VES 60胶束溶液的粘弹性参数G′,G″和η 增大,tanδ减小,即弹性增强而粘性相对减弱。图5表2参6。A cationic surfactant composition for hydrofracturing fluids VES-60, is prepared from a C_(16)/C_(18)-alkyltrimethyl ammonium salt and auxiliaris. The micelle forming ability of VES-60/water and other systems is studied and the ESEM photos of a wormlike and a sheet framework micelles are demostrated. The changes in viscosity at 70℃ of the micelle gels formed from some 5 vol.% CTAB/NaSal or NaSal+KNO_3/water systems are determined and the synergistic effect between the two salts is discussed. A three-stage dynamics of micelle formation of 4% VES-60 solution at 10—40℃ and at 10 s^(-1) is ascertained: dispersed micella chains and low viscosity; chain association and fast enhancement in viscosity; and chains in dynamical liquilibrium and more and less stable viscosity. The viscosity of 4% VES-60 micelle solution at 170 s^(-1) decreases with temperature raise and changes slightly in range 50—80℃, being of ～60 mPas, and lowers fast at >80℃. The rheologic behavior of 4% VES-60 micelle solution at 20℃ fits to Hershel-Bulkley's model with k′=8.664 Pas^(n′),n′=0.267 8, and τ_y=5.4 Pa. For VES-60 micelle solution at 30℃, the viscoelastic characteristics G′,G″ and η~* increase and tan δ decreases, that is, the elasticity enhances and the viscosity comparatively weakens, with increasing volume fraction of VES-60..

关 键 词：粘弹性胶束压裂液 流变性质 表面活性剂 VES-60 低渗透油气藏 

分 类 号：TE357.12[石油与天然气工程—油气田开发工程]