摘要
常规滑溜水压裂液已经成功运用于页岩等非常规油气储层压裂中,但其携砂性能差、渗吸采收率低的问题仍然未得到有效解决。针对这一问题,合成一种新型纳米变黏滑溜水,该体系不仅具有常规滑溜水优异的减阻特性,还兼具了较强的变黏携砂性能。另外,该体系含有优选的纳米乳液,可将混合润湿或油润湿的页岩油储层改性为水润湿,具有强渗吸置换作用。通过一系列室内实验评价可以发现:碳纳米渗吸(carbon nano imbibition,CNI)体系纳米变黏滑溜水为乳液状,可实时在线配制,通过调整其浓度,黏度发生显著变化,达到低浓度时高减阻、高浓度时强携砂的效果,残渣含量及对储层伤害低,实现了一剂多效,同时它还具有常规滑溜水与瓜胶携砂液所没有的改性驱油的效果,从而提高原油采收率。纳米变黏滑溜水同时具备高减阻、高携砂、低伤害和强置换的性能,可作为未来页岩油压裂的主体压裂液。
Conventional slickwater fracturing fluid has been successfully used in the fracturing of unconventional oil and gas reservoirs such as shale,but the problems of poor sand-carrying performance and low imbibition recovery have not been effectively solved.To solve this problem,a new nano variable-viscosity slickwater was synthesized,which not only had excellent drag reduction characteristics of conventional slickwater,but also had strong variable-viscosity sand-carrying performance.In addition,the system contained the preferred optimized nano-emulsion,which can modify the shale oil reservoir wetted by mixing or oil to be wetted by water,and had the effect of strong imbibition displacement.Through a series of laboratory experimental evaluation,it can be found that the carbon nano imbibtion(CNI)system nano variable-viscosity slickwater is in the form of emulsion,which can be prepared online in real time.By adjusting its concentration,the viscosity changes significantly,reaching the effect of high drag reduction at low concentration and strong sand carrying at high concentration,and the residue content and damage to the reservoir are low,realizing multiple effects in one dose.At the same time,it has the effect of modified oil displacement that conventional slickwater and guar sand-carrying fluid do not have,to improve crude oil recovery.Nano variable-viscosity slickwater has the properties of high drag reduction,high sand carrying,low damage and strong replacement at the same time,and can be used as the main fracturing fluid for shale oil fracturing in the future.
作者
刘汉斌
唐梅荣
吕宝强
刘锦
柏浩
郎皞
周福建
姚二冬
LIU Han-bin;TANG Mei-rong;L Bao-qiang;LIU Jin;BAI Hao;LANG Hao;ZHOU Fu-jian;YAO Er-dong(Oil&Gas Technology Research Institute,Changqing Oilfield Company,Xi'an 710021,China;Unconventional Natural Gas Institute,China University of Petroleum,Beijing 102249,China)
出处
《科学技术与工程》
北大核心
2023年第8期3244-3251,共8页
Science Technology and Engineering
基金
国家自然科学基金(52004306)
中国石油天然气集团有限公司-中国石油大学(北京)战略合作科技专项(ZLZX2020-01,ZLZX2020-02)
国家科技重大专项(2016ZX05030005,2016ZX05051003)。
关键词
变黏滑溜水
纳米乳液
静态和动态携砂
渗吸置换
variable-viscosity slickwater
nano emulsion
static and dynamic sand carrying
imbibition displacement
