油相组成及相态变化对含蜡油包水乳状液稳定性的影响  

Effects of Oil Composition and Phase Change on the Stability of Water-in-waxy Model Oil Emulsions

作　　者：刘真[1] 李传宪[2] LIU Zhen;LI Chuan-xian(Sinopec Petroleum Engineering Corporation,Dongying 257029,China;College of Pipeline and Civil Engineering,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]中石化石油工程设计有限公司,东营257029 [2]中国石油大学(华东)储运与建筑工程学院,青岛266580

出　　处：《科学技术与工程》2025年第4期1428-1437,共10页Science Technology and Engineering

基　　金：山东省自然科学基金面上项目(ZR2022ME115)。

摘　　要：在油田开发过程中,原油与水极易形成乳状液,增大了原油处理难度,而原油组成尤其是原油中石蜡的析出对乳状液稳定性的影响显著。从油相组成影响相态变化进而改变乳状液稳定性的独特角度出发,通过乳状液稳定性测试、油水界面特性测试、析蜡特性测试、沥青质分散稳定性测试、显微观察等方法开展系统研究。研究发现,随着油相中液体石蜡含量的增大,蜡晶的形貌从细小颗粒变为较大的团聚蜡晶,沥青质的分散稳定性也随之下降。测量温度显著影响乳状液稳定性:测量温度为30℃时,增大液体石蜡含量可以降低界面张力、提高扩张模量,这有助于液滴保持分散,在一定程度上提高乳状液的稳定性;测量温度为15℃时,增大液体石蜡含量促进结构更强的蜡晶网络形成,通过束缚水滴大幅提高乳状液稳定性。此外,研究还发现,在乳化水滴表面析出的蜡晶可形成一层蜡晶界面膜,从而进一步提高界面膜强度和乳状液稳定性。基于上述研究,首次提出油相组成对沥青质与石蜡协同稳定模拟原油乳状液的影响机理模型。In the process of oilfield development,the formation of emulsion between crude oil and water is quite common,which increases the difficulty of crude oil treatment.The composition of crude oil,especially the precipitation of paraffin wax,has significant influence on the stability of the emulsion.From the unique perspective that the oil composition affects the phase change and then further determines the emulsion stability,a systematic study was carried out with the methods of emulsion stability test,oil-water interfacial characteristic test,wax precipitation test,asphaltene dispersion stability test,and microscopic observation.It is observed that increasing the amount of liquid paraffin in the solvents leads to a change in the form of wax crystals from fine particles to larger agglomerated wax crystals,and the asphaltenes dispersion stability decreases along with it.Test temperature can significantly affect emulsion stability.At 30℃,increasing the percentage of liquid paraffin reduces the interfacial tension,increases the interfacial dilatational modulus,and enhances the structure of the interfacial film.This contributes to the formation of small droplets and improves emulsion stability to a certain extent.At 15℃,by contrast,increasing the liquid paraffin content promotes the development of a more structured wax crystals network,which significantly enhances emulsion stability by binding water droplets.Additionally,it is also found that a wax crystal interfacial film could be formed at the surface of the emulsified drops,which improves further the interfacial film strength and emulsion stability.Based on the above findings,an influencing mechanism model is presented concerning the synergistic stabilization of model oil emulsion containing asphaltene and paraffin wax.

关 键 词：油包水乳状液 油相组成 石蜡 油水界面 稳定性 

分 类 号：TE866[石油与天然气工程—油气储运工程]