纳米颗粒强化泡沫压裂液的构建及其稳泡机理研究  

Preparation of nanoparticle-stabilized foam fracturing fluid and its foam stabilization mechanism

作　　者：杨兆中 郑南鑫 朱静怡 李小刚 YANG Zhaozhong;ZHENG Nanxin;ZHU Jingyi;LI Xiaogang(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China;College of Chemistry and Chemical Engineering,Southwest Petroleum University,Chengdu,Sichuan 610500,China)

机构地区：[1]油气藏地质及开发工程国家重点实验室,四川成都610500 [2]西南石油大学化学化工学院,四川成都610500

出　　处：《油气藏评价与开发》2023年第2期260-268,共9页Petroleum Reservoir Evaluation and Development

基　　金：西南石油大学“启航计划”项目“耐温耐盐新型微生物多糖泡沫体系的构建及其压裂应用研究”(2021QHZ035)。

摘　　要：SiO_(2)纳米颗粒(SNP)与表面活性剂的协同作用可为构建适用于恶劣地层条件下的泡沫压裂液提供一种新思路。实验评估了SiO_(2)纳米颗粒与5种表面活性剂协同稳泡能力,基于泡沫综合值筛选了最优泡沫体系。通过对优选出的泡沫压裂液体系进行携砂性、黏弹性、剪切性、稳定性评价,分析纳米颗粒对压裂液性能的改良。同时利用光学显微镜、环境扫描电子显微镜观察揭示SiO_(2)纳米颗粒稳泡机理。体系筛选实验表明:阳离子型表面活性剂TTAB与SiO_(2)纳米颗粒的协同作用最明显,泡沫综合值达15288 mm·s,析液半衰期提升了145%。性能评价实验表明:SiO_(2)纳米颗粒能提升界面液膜的弹性模量,提高液膜对支撑剂的支撑能力,减小沉降速率,有利于泡沫将支撑剂带入更深的裂缝当中;SiO_(2)纳米颗粒还能提高液膜表面的粗糙度,强化泡沫压裂液的抗剪切能力;在体系中加入支撑剂会削弱泡沫的稳定性,陶粒的削弱作用强于石英砂,小粒径的削弱作用强于大粒径的削弱作用。机理研究实验表明:泡沫微观结构中观察到SNP在Plateau边界(3个气泡的交界区)聚集堵塞排液通道,这说明纳米颗粒能够阻止泡沫的粗化和排液,宏观稳定性上表现为气泡数量更多、尺寸更小、分布更均匀。The synergistic effect of SiO_(2)nanoparticles(SNP)and surfactants can provide a new idea for the preparation of foam fracturing fluid suiTable for harsh formation conditions.In order to prove it,the synergistic foam stabilization ability of SNP and five types of surfactants is evaluated,and the optimal foams system is selected based on the foams comprehensive value.The proppant carrying ability,rheology,and stability of the selected foam fracturing fluid system are evaluated,and the performance improvement of the fracturing fluid by SNP is analyzed.At the same time,the optical microscope observation and SEM experiment are used to reveal the foam stabilization mechanism of SNP.The system screening experiments show that the synergistic effect of TTAB and SNP is the most obvious.The comprehensive foam value reaches 15288 mm·s,and the half-time of water drainage increases by 145%.The performance evaluation experiments show that SNP can improve the elastic modulus of the interfacial liquid film,improve the proppant supporting capacity of the liquid film,reduce the settling velocity of proppant which help foam fracturing fluid bring proppants into deeper fractures.SNP can also improve the surface roughness of liquid film and thus enhance the shear resistance of foam fracturing fluid.Adding proppants to the system can weaken the stability of foam.The weakening effect of ceramsite is stronger than that of quartz sand,and the weakening effect of high mesh size is stronger than that of low mesh size.The stabilization mechanism study is revealed by the SNP aggregation at Plateau is observed in the foam microstructure which can block the drainage channels.Moreover,SNP could prevent the coarsening and drainage of foam.By the macroscopic observation,SNP-stabilized bubbles are more stable in term of more bubble number,smaller bubble size and more uniform bubble size distribution.

关 键 词：泡沫压裂液 SiO_(2)纳米颗粒 体系筛选 泡沫性能评价 稳泡机理 

分 类 号：TE357[石油与天然气工程—油气田开发工程]