注入水成分对油藏中液固界面Zeta电位的影响  

Effect of Injected Water Composition on Zeta Potential of Liquid-Solid Interface in Reservoir

作　　者：叶仲斌[1,2] 徐金腾 印风军 施雷庭[1] 陈洪[1] 李亚丽 YE Zhong-bin;XU Jin-teng;YIN-Feng jun;SHI Lei-ting;CHNE Hong;LI Ya-li(School of Chemistry and Chemical Engineering,Southwest Petroleum University,Chengdu 610500,Sichuan,China;School of Petroleum and Gas Engineering,Southwest Petroleum University,Chengdu 610500,Sichuan,China)

机构地区：[1]西南石油大学石油与天然气工程学院,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：《精细化工》2018年第10期1765-1771,共7页Fine Chemicals

基　　金：“十三五”国家科技重大专项项目(2016ZX05025-003)~~

摘　　要：为了研究低矿化度水成分对油藏中岩石和原油表面带电量、润湿性、油膜脱附量的影响及三者间的关系,配制了离子类型、离子质量浓度、溶液pH不同的低矿化度水,并分别将其与模拟岩石和原油样品混合后测定Zeta电位值、与含油岩心切片接触测表面润湿角、与含油岩石颗粒混合测表面油膜脱附量。结果表明,Na~＋、Ca^（2＋）和Mg^（2＋）溶液对原油和岩石表面带电量的影响主要取决于离子价态,二价离子对其带负电量影响更大。同种离子,随着离子质量浓度的增加,原油和岩石表面负电量减小。pH升高对原油和岩石表面带电量的影响与溶液所含离子的价态和水解性有关,Ca^（2＋）、Mg^（2＋）溶液所测得的负电量比Na~＋溶液低,且随着pH的增加带负电量呈现先增大后减小的趋势,这种趋势与Na~＋不同。此外,低矿化度水成分变化对原油和岩石表面带电量的影响规律与对油膜脱附量的影响规律一致;当油藏液固界面Zeta电位的绝对值减小时,接触角增大、油膜脱附量减少。In order to study the effect of low-salinity water composition on the surface charge, wettability and oil film desorption capacity of rock and crude oil as well as the relationship among them, a series of low-salinity water with different ions, different ion mass concentrations and different pH were prepared. Then, these samples were mixed with simulated rocks and crude oil samples to measure Zeta potential, solid/brine water/crude oil three-phase contact angle and oil film desorption capacity on the surface of rock particles, respectively. The results showed that the effects of Na~＋, Ca^（2＋） and Mg^（2＋） on the surface charges of crude oil and rock mainly depended on the ionic valence state, and the divalent ions had a more significant influence on the negative charge. Moreover, the negative charges detected in solutions of the same ions decreased with the increase of the concentration of ions. The effect of pH increasing on negative charge was related to the ionic valence state and hydrolysis of solution. The negative charges measured in Ca^（2＋）or Mg^（2＋）solution were less than that of Na~＋ solution, and increased initially and then decreased with the pH increasing, which was different from the latter. Besides, the influence of compositional variation of low-salinity water on the surface charges of crude oil and rock was consistent with the influence on the interfacial contact angle and the oil film desorption capacity. When the absolute value of Zeta potential decreased, the interfacial contact angle increased and the oil film desorption capability decreased.

关 键 词：油藏液固界面 低矿化度水 ZETA电位 润湿角 油膜脱附量 油田化学品与油品添加剂 

分 类 号：O646.1[理学—物理化学]