Gemini阳离子/含氟阴离子表面活性剂混合体系的界面润湿调控及解水锁机制研究  

Interfacial Wettability Regulation and Water Locking Mechanism of Gemini Cationic/Fluorine-Containing Anionic Surfactant Mixture

作　　者：齐宏伟[1] 赖璐[2] QI Hongwei;LAI Lu(North China Oil and Gas Company,SINOPEC,Zhengzhou 450006,China;College of Chemistry and Environmental Engineering,Yangtze University,Jingzhou 434023,China)

机构地区：[1]中国石化华北油气分公司,河南郑州450006 [2]长江大学化学与环境工程学院,湖北荆州434023

出　　处：《化学与生物工程》2024年第5期31-36,共6页Chemistry & Bioengineering

基　　金：国家自然科学基金面上项目(52374030)。

摘　　要：为有效解决低渗透致密砂岩气藏开采普遍存在的水锁伤害问题,研究了Gemini阳离子表面活性剂双季铵盐BQ-16和含氟阴离子表面活性剂全氟辛基磺酸钾(PPS)在降低表面张力和润湿调控方面的协同作用,并探究了BQ-16/PPS表面活性剂混合体系的润湿调控及解水锁机制。结果表明,当PPS的摩尔分数(α_(PPS))为0.7时,BQ-16/PPS表面活性剂混合体系的表面张力达到最低,低于任一纯组分,此时BQ-16/PPS表面活性剂混合体系接近电中性;BQ-16和PPS在岩心表面润湿调控方面表现出协同效应,当BQ-16/PPS表面活性剂混合体系总浓度为1×10^(-4)mol·L^(-1)、α_(PPS)为0.7时,盐水滴接触角最大,达到84.23°;BQ-16/PPS表面活性剂混合体系(α_(PPS)=0.7)在石英砂表面的吸附过程符合准二级动力学方程和Freundlich等温吸附模型,低浓度时为单分子层吸附,高浓度时为多分子层吸附;BQ-16/PPS表面活性剂混合体系(α_(PPS)=0.7)可将岩心的液体饱和度降至0.410,并将渗透率恢复值提高至0.78,说明BQ-16/PPS表面活性剂混合体系可有效解决水锁伤害,这主要与混合体系能够显著降低表面张力并通过在岩心表面的吸附改变岩心表面润湿性有关。In order to effectively solve the problem of water locking damage in the exploitation of tight sandstone gas reservoirs with low permeability,we investigated the synergistic effect of Gemini cationic surfactant biquaternary ammonium salt BQ-16 and fluorine-containing anionic surfactant PPS on reducing surface tension and wettability regulation,and explored interfacial wettability regulation and water locking mechanism of BQ-16/PPS surfactant mixture.The results show that when the molar fraction of PPS(α_(PPS))is 0.7,the surface tension of BQ-16/PPS surfactant mixture is the lowest,which is lower than that of any pure component,and the BQ-16/PPS surfactant mixture is close to electroneutic.BQ-16 and PPS show a synergistic effect in wettability regulation on core surface.When the total concentration of BQ-16/PPS surfactant mixture is 1×10^(-4)mol·L^(-1)and theα_(PPS)is 0.7,the contact angle of brine droplets reaches the maximum of 84.23°.The adsorption process of BQ-16/PPS surfactant mixture(α_(PPS)=0.7)on quartz sand surface presents a single-molecular-layer adsorption at low concentrations and a multi-molecular-layer adsorption at high concentrationis,which is consistent with pseudo-second order kinetic equation and Freundlich isothermal adsorption model.BQ-16/PPS surfactant mixture(α_(PPS)=0.7)can reduce the liquid saturation of the core to 0.410,and improve the permeability recovery value to 0.78,indicating that BQ-16/PPS surfactant mixture can effectively solve water locking damage.This is mainly related to the mechanism that the mixture can significantly reduce the surface tension and change the wettability of the core surface through adsorption on the core surface.

关 键 词：GEMINI阳离子表面活性剂 阴、阳离子表面活性剂复配 润湿调控 水锁伤害 

分 类 号：TQ423.1[化学工程] TE258[石油与天然气工程—油气井工程]