一体化生物复合乳液及在碳酸盐岩体积加砂压裂中的应用  

An Integrated Bio-Compounded Emulsion and Its Use in SRV Fracturing of Carbonate Rocks with Sand-Carrying Fracturing Fluids

作　　者：胡艾国[1] 林波 严向阳 李克智[1] 杜良军 吴洋[3] 陈恒 HU Aiguo;LIN Bo;YAN Xiangyang;LI Kezhi;DU Liangjun;WU Yang;CHEN Heng(Petroleum Engineering Technologv Research Institute,North China Oil and Gas Company,Sinopec,Zhengzhou,Henan 450000;Sichuan Shenhe New Material Technology Co.Ltd,Chengdu,Sichuan 610500;College of Chemistry and Chemical Engineering,Southwest Petroleum University,Chengdu,Sichuan 610500)

机构地区：[1]中国石化华北油气分公司石油工程技术研究院,郑州450000 [2]四川申和新材料科技有限公司,成都610500 [3]西南石油大学化学化工学院,成都610500

出　　处：《钻井液与完井液》2024年第6期806-815,共10页Drilling Fluid & Completion Fluid

基　　金：中国石化华北油气分公司重大科研项目“大牛地气田DK13井区碳酸盐岩储层钻完井关键技术”(KJGLB-2022-12)。

摘　　要：针对碳酸盐岩体积加砂压裂的难点,以减阻剂速溶、高效增黏和在线变黏一体化为出发点,将小分子改性生物单体与丙烯酰胺、水解度控制单体、微电荷单体等接枝共聚,引入相关功能助剂,制备出有效含量高、功能复合的一体化生物复合乳液,构建高减阻强携砂压裂液体系并制定针对性的用液方案、工艺优化,实现碳酸盐储层控缝高、造复杂缝网、控黏增砂、充分改造的目标。该乳液有效含量、水解度、分子量分别控制在30%左右、40%~50%、1200~1300万,微电荷单体2.0%和小分子生物单体0.6%时性能最优,溶解时间低于20 s,3 min增黏率达90%以上,CAC1,CAC2分别为1.79 g/L、3.89 g/L;对压裂液综合性能评价表明:低黏液、中黏液、高黏液降阻率分别可达75%、70%、60%以上,降阻率保持率96%以上;高黏液、中黏液在110℃、170 s^(−1)剪切90 min后黏度分别保持在45~50 mPa·s、20~25 mPa·s;中黏液(0.4%)黏弹性表征Tanδ<0.4就具有良好的携砂性能,支撑剂沉降速率低至0.1 cm·s^(−1);压裂液破胶液黏度低于3 mm^(2)/s,表面张力27 mN/m以下,残渣含量低至20 mg/L以下。该技术在鄂尔多斯盆地碳酸盐岩井进行体积加砂压裂先导实验及规模化应用超过30井次,液体性能稳定,加砂完成率95%以上,取得了良好的增产效果,为致密碳酸盐岩开发提供了强有力的技术手段。Using low-molecular-weight modified bio-monomers,acrylamide monomers,hydrolysis control monomers,microelectric-charged monomers as well as other functional additives,an integrated bio-compounded emulsion is developed through grafting polymerization to deal with the problems encountered in the stimulated-reservoir-volume(SRV)fracturing of carbonate reservoirs with sand-carrying fracturing fluids.In developing the integrated bio-compounded emulsion,focuses are placed on the fast dissolution of the drag reducers used and fast online viscosifying of the fracturing fluid.The integrated bio-compound emulsion developed has high rate of production and multiple functions.Using this integrated bio-compound emulsion,a sand-carrying fracturing fluid of high lubricating capacity high suspending capacity is developed.An optimized specific fracturing program is designed for carbonate reservoir stimulation,aimed at controlling the height of the fractures,producing complex fracture network,controlling viscosity and increasing sand content as well as stimulating the reservoir to the full.The effective concentration,degree of hydrolysis and molecular weight of the emulsion are±30%,40%-50%and(1,200-1,300)×10^(4),respectively.At micro-electriccharged monomers concentration of 2.0%and low-molecular-weight modified bio-monomers concentration of 0.6%,the emulsion produced has the optimum properties;the dissolution time is less then 20 s,the 3-min viscosifying rate is more than 90%,and the CAC_(1) and CAC_(2) are 1.79 g/L and 3.89 g/L,respectively.Evaluation of the general performance of the fracturing fluid formulated with the emulsion showed that the percent drag reductions of the low-viscosity fracturing fluid,the medium-viscosity fracturing fluid and the high-viscosity fracturing fluid are at least 75%,70%and 60%,respectively.The sustained drag reduction can be maintained at 96%or higher.The viscosities of the high-viscosity and the medium-viscosity fracturing fluids which are sheared 90 min at 110℃and 170 s^(−1)are 45-50 mPa·

关 键 词：碳酸盐岩 体积加砂压裂 复杂缝网 生物复合乳液 低黏高弹性 一体化 

分 类 号：TE357.12[石油与天然气工程—油气田开发工程]