强缓速低摩阻低伤害纳米均相缓速酸

Nano Homogeneous Phase Retarded Acid with Strong Retardation，Low friction and Low Damage

崔 波 冯浦涌 荣新明 姚二冬 王 顺 周福建 吴 广

CUI Bo FENG Puyong RONG Xinming YAO Erdong WANG Shun ZHOU Fujian WU Guang

针对碳酸盐岩储层改造乳化酸高摩阻、稠化酸聚合物残渣伤害问题，首先通过拟三元相图，以非离子型表面活性剂（三苯乙烯基苯酚聚氧乙烯醚）、阳离子型表面活性剂（季铵盐）、助表面活性剂（醇）为原料制备纳米乳液，然后将 20%盐酸、5%纳米乳液、0.1%减阻剂（阳离子聚丙烯酰胺）及功能型添加剂混合制得纳米均相缓速酸。采用旋转岩盘仪、扫描电镜、EDS能谱仪、电导率仪、粒度分析仪、界面张力仪、润湿角测定仪、摩阻仪、酸蚀裂缝导流仪、岩心流动仪等评价了纳米均相缓速酸的性能，分析了缓速机理、高酸蚀裂缝导流机理和溶垢机理。结果表明，纳米均相缓速酸是一种内相为油、外相为酸的纳米均相分散体系，粒径分布为8～100 nm；其具备强缓速（缓速率大于 90%）、低摩阻（降阻率大于 75%）、低黏、低伤害和高酸蚀裂缝导流性能；可同时溶解有机垢和无机垢，对沥青和碳酸盐岩的溶解率分别为6.91%和100%；可解除储层乳化、水锁、润湿改性伤害。纳米均相缓速酸通过带负电纳米乳液吸附在带正电灰岩表面，建立酸岩“隔离屏障”，实现强缓速；通过差异化酸蚀及黏性指进，实现高酸蚀裂缝导流；通过纳米乳液特殊的油水互溶结构，实现有机垢和无机垢的同时解除。该体系在海上油田现场成功应用，增产效果显著，对碳酸盐岩储层深部改造及多重伤害解除具有重要意义。

To solve the problem of high friction of emulsified acid and damage of gelled acid polymer residue in carbonate reservoir stimulation，nanoemulsion was prepared using non-ionic surfactant（tristyrylphenol polyoxyethylene ether），cationic surfactant （quaternary ammonium salt），and cosurfactant（alcohol）as raw materials through pseudo-ternary phase diagram. Then，20% HCl， 5% nanoemulsion，0.1% resistance reducing agent（cationic polyacrylamide），and functional additives were mixed to prepare nano homogeneous phase retarded acid. The properties of the homogeneous phase retarded acid were systematically analyzed and evaluated using rotating rock disc instrument，scanning electron microscope，EDS spectrometer，conductivity meter，particle size analyzer，interfacial tensiometer，wetting angle tester，friction tester，acid-etched fracture conductivity meter，and core flow meter. The retardation mechanism，high acid-etched fracture conductivity mechanism and scale dissolving mechanism were analyzed. The results showed that the nano homogeneous phase retarded acid was a kind of nano homogeneous dispersion system with oil in the inner phase and acid in the outer phase. The particle size distribution was 8—100 nm. It had strong retardation（retarded rate greater than 90%），low friction（friction reducing rate greater than 75%），low viscosity，low damage and high acid-etched fracture conductivity. It could dissolve organic scale and inorganic scale simultaneously. The dissolution rate of asphalt and carbonate rock was 6.91% and 100% ，respectively. It could remove the damage from reservoir emulsification，water lock，and wetting modification. Nano homogeneous phase retarded acid adsorbed on the surface of positive electric limestone by negatively charged nanoemulsion，and then the“isolation barrier”between acid and rock was established to achieve strong retardation. Through differentiated acid-etched and viscous fingering，the high acid-etched fracture conductivity was realized. Through the special oil-water miscible structure of nanoemulsion，organic scale and inorganic scale could be removed simultaneously. The system was successfully applied on offshore oilfields with remarkable effect of increasing production，which was of great significance for the deep treatment of carbonate reservoirs and multiple damage removal.

10.19346/j.cnki.1000-4092.2024.03.007