深层煤岩气高效能变黏压裂液及在极限体积压裂中的推广应用  

Efficient and variable viscosity fracturing fluid of deep coal rock gas and popularization in ultimate volume fracturi

作　　者：林波 陈帅 严向阳 陈萌琦 杜良军 陈恒 鲁红升[3] 孙帅 LIN Bo;CHEN Shuai;YAN Xiangyang;CHEN Mengqi;DU Liangjun;CHEN Heng;LU Hongsheng;SUN Shuai(Sichuan Shenhe New Material Technology Co.,Ltd.,Chengdu 610500,China;Petro China Coal Bed Methane Company Limited,Beijing 100028,China;College of Chemistry and Chemical Engineering,Southwest Petroleum University,Chengdu 610500,China)

机构地区：[1]四川申和新材料科技有限公司,四川成都610500 [2]中石油煤层气有限责任公司,北京100028 [3]西南石油大学化学化工学院,四川成都610500

出　　处：《煤炭学报》2025年第2期1162-1174,共13页Journal of China Coal Society

基　　金：四川省工业发展资金产业技术研发和创新能力提升(绿色低碳优势产业创新任务揭榜攻关)资助项目(2022JB001202303)。

摘　　要：极限体积压裂技术是深层煤岩气获得高产工业气流的有效手段,而压裂液是在该技术基础上充分“打碎”煤层、形成饱填砂复杂裂缝网络、实现煤岩增渗—促解吸的关键,充分满足现场工况、施工工艺和煤岩物性特征要求是煤岩气压裂液研究的重点。以高稳定性、速溶、低剂高效能和在线变黏一体化的减阻剂研发为着力点,通过无机盐刺激响应材料引入、开关型反相乳液聚合技术设计、多元共聚条件控制和促解吸剂复配等制备得到开关型乳液减阻剂。结合基础性能表征及评价,厘清了乳液减阻剂重要参数对压裂液性能的影响规律,确定水解度50%~55%、分子量1800万左右、有效质量分数29%~34%的优化条件,得到预期的煤岩气专用减阻剂SFY-2,稳定性提高至50 d以上,抗低温−15℃以下,溶解时间降低至10 s,3 min增黏率达90%以上且增黏能力强,解决了常规乳液减阻剂稳定性和速溶性之间的突出矛盾,也为深层煤岩气极限体积压裂在线一体化施工提供了保障。借助SFY-2优势,契合煤岩气极限体积压裂设计思路构建了高效能变黏压裂液体系,制定变黏控制方案和施工工艺优化,实现充分“打碎”煤岩,造复杂缝网并饱填砂有效支撑的目标。对压裂液性能评价表明:高黏液、中黏液在70℃、170 s^(−1)~1500 s^(−1)~100 s^(−1)模拟变剪切后黏度分别保持在35、20 mPa·s左右;高黏液、中黏液、低黏液降阻率分别可达66%、72%、77%以上,得益于压裂液良好的剪切稀释性,高剪切状态下高黏液、中黏液降阻率保持率超过100%;建立了压裂液悬砂性能与黏弹性参数tanδ的对应关系,当SFY-2体积分数超过0.2%(tanδ=0.84)后压裂液沉砂速度明显降低,体积分数达到0.4%(tanδ=0.395)后黏弹性显著,具有良好的携砂性能,利于高强度连续加砂进行缝网饱和支撑,并增大缝网有效改造体积;压裂液破胶后几乎无残渣,表面张Limit volume Fracturing Technology is the effective means to achieve high yield industrial flow for deep coal rock gas,on the basis of this technique,fracturing fluid is the key to fully“Breaking”coal seam,establish filling sand complex crack network,realize Anatonosising-Desorption promote for coal rock,therefore,the focus of coal rock gas fracturing fluid research is fully meet the field condition,construction technology and physical characteristics of coal rock.Focus on the research of the friction reducer with high stability,instant,low dosage but high efficiency and on-line viscosity change integration,a switch-type emulsion resistance reducer was prepared by introducing inorganic salt stimulation response material,designing switch reverse phase emulsion polymerization technology,condition controling of Multicomponent copolymerization and compounding desorption promote agent.The influence law on fracturing fluid performance by important parameters of emulsion resistance reducer was clarified by combining Characterization and Evaluation of basic performance,the expected coal rock gas special resistance reducing agent SFY-2 was obtained with the optimization conditions of hydrolysis ratio for 50%~55%,molecular weight for about 18 million and effective content for 29%~34%,the stability is improved to over 50 days,the low temperature resistance is below−15℃,the dissolution time is reduced to 10 s,the viscosity increasing rate is over 90%in 3 min,and the viscosity increasing ability is strong,the highlight contradiction of convention emulsion friction reducer between stability and instant solubility was resolved,as well as provided a guarantee for the online integrated construction of deep coal rock gas Ultimate volume Fracturing.By taking the advantage of SFY-2,a efficient and variable viscosity fracturing fluid is constructed to fit the design idea of coal rock gas Ultimate volume Fracturing,the variable viscosity control scheme is formulated and the construction technology is optimizated to achieve the

关 键 词：深层煤岩气 极限体积压裂 复杂缝网改造 刺激响应 低黏高弹性 变黏控制 促解吸 

分 类 号：P618.11[天文地球—矿床学]