低渗高盐油藏两性离子-阴离子表面活性剂复配驱油协同效应研究  

Study on Synergistic Effect of Amphoteric and Anionic Surfactants in Compound Flooding of Low-Permeability and High-Salt Oil Reservoirs

作　　者：毛小倩 扈福堂[1] 朱秀雨[1] 党杨斌 杜春保 吴亚[2] MAO Xiaoqian;HU Futang;ZHU Xiuyu;DANG Yangbin;DU Chunbao;WU Ya(Drilling and Production Technology Research Institute,PetroChina Qinghai Oilfield Company,Dunhuang,Gansu 736202,China;College of Chemistry and Chemical Engineering,Xi’ an Shiyou University,Xi’ an,Shaanxi 710065,China)

机构地区：[1]青海油田钻采工艺研究院,甘肃敦煌736202 [2]西安石油大学化学化工学院,陕西西安710065

出　　处：《西安石油大学学报（自然科学版）》2022年第3期100-106,共7页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：国家自然科学基金青年项目(22002117);陕西省重点研发计划(项目编号2019KW-061);陕西省陆相页岩气成藏与开发重点实验室(筹)开放课题资助。

摘　　要：在地层水(矿化度为183.4 g/L,钙镁离子总浓度为1.4 g/L)中,通过优化两性离子DB-18和阴离子磺酸盐AS-1表面活性剂的复配比,研究了二者在耐盐性、降低界面张力、乳化性、岩心表面润湿性、静态吸附方面的协同效应,并考察了该复配体系提高原油采收率能力及岩心恢复情况,探索影响该体系协同作用的因素。研究结果表明,复配表面活性剂总浓度为0.3%,DB-18和AS-1质量比大于1000∶12时体系对地层水耐盐性好,而且DB-18与低浓度的AS-1复配能够显著降低原油/地层水的界面张力至10^(-2) mN/m数量级。同时该体系对乳化的原油/地层水相对稳定,使油湿性储层岩心切片向水湿转变(接触角128.5°至77.1°),高盐度水没有明显影响复配体系在岩心表面润湿性。进一步的岩心驱替实验显示当驱油剂注入量0.3 PV时,采收率提高13%以上,且注入驱油剂后岩心渗透率恢复值达85%以上。The composite solutions(with different mass ratio)of amphoteric surfactant DB-18 and anionic sulfonate surfactant AS-1 were prepared with formation water(the salinity is 183.4 g/L and the total mass concentration of calcium and magnesium ions is 1.4 g/L).The synergistic effects of two surfactants in salt resistance,reducing interfacial tension,emulsification,core surface wettability and static adsorption were studied,and their composite ratio is optimized.The crude oil recovery improving ability and core permeability recovery ability of the optimal composite system are evaluated through the core displacement experiment,and the factors affecting the synergistic effect of two surfactants are explored.The results show that the system has good salt resistance to formation water when the mass fraction of compound surfactant is 0.3%and the mass ratio of DB-18 and AS-1 is greater than 1000∶12,and the combination of DB-18 and low concentration AS-1 can significantly reduce the interfacial tension between crude oil and formation water to the order of 10^(-2) mN/m.At the same time,the system is relatively stable to emulsified crude oil/formation water,which makes the core slice of oil wet reservoir change to water wet(contact angle from 128.5°to 77.1°).High salinity water does not significantly affect the wettability of the composite system on the core surface.The core displacement experiment shows that when the injection amount of oil displacement agent is 0.3 PV,the oil recovery is increased by more than 13%,and the core permeability recovery rate is more than 85%after the injection of oil displacement agent.

关 键 词：强化采油 磺酸盐表面活性剂 两性离子表面活性剂 复配驱油 协同效应 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程]