添加剂对含盐四氯化碳-水乳状液的稳定作用

在恒定乳化机转速和白炭黑含量的条件下,以白炭黑作为固体粉末稳定剂制备了四氯化碳-水乳状液,用恒定含量的氯化钾作为背景电解质,采用电导法研究了不同含量的聚乙二醇-600(PEG-600)和吐温-80(Tween-80)添加剂对含盐四氯化碳-水(体积比为1∶1)乳状液的稳定作用,通过提出增比电导率和初始分层速率常数的概念对乳状液的动力学稳定性进行了分析。分析结果表明,PEG-600在低含量时对乳状液有聚沉作用,加快了油水分层速率;在中等含量时对乳状液具有一定的稳定作用;在高含量时乳状液出现转相现象,又导致乳状液不稳定。添加0.20%(质量分数)的Tween-80后,乳状液初始分层速率常数从0.098min-1急剧降至0.009min-1,未出现乳状液转相现象。     

纳米白炭黑对含盐四氯化碳-水乳状液稳定性的影响

 以纳米白炭黑作为固定稳定剂, 在不同乳化机转速(ω) 和白炭黑质量分数(w)的条件下, 制备了一系列四氯化碳-水(体积比1:1)的乳状液, 用氯化钾为背景电解质, 电导法测定了这些乳状液富油相在不同陈化时间的电导率. 以增比电导率κ_r和初始分层速率常数k_eo的概念, 分析了乳状液的动力学稳定性. 结果表明, 当白炭黑质量分数w=0.2%时, 乳状液的初始分层速率常数k_eo随乳化机转速ω的增加而线性下降; 当ω=4000r/min时, 乳状液的初始分层速率常数k_eo随白炭黑质量分数w的增加而下降, 但w在0～0.5%范围时下降幅度大, w>0.5%时下降缓慢.     

CCl_4/H_2O/CTAB乳状液的稳定性研究

制备了不同组成的 CCl4/ H2 O/十六烷基三甲基溴化铵 (CTAB)乳状液 ,用电导法测定了含与不含添加剂 (正已醇和水杨酸钠 )条件下 ,乳状液富油相区不同时间的电导率。为了寻找乳状液的稳定性与电导率之间的关系 ,提出了富油相增比电导率的概念 ,并由增比电导率与时间的关系讨论了乳状液的稳定性     

CCl0/H2O/CTAB乳状液的稳定性研究

制备了不同组成的CCl4/H2O/十六烷基三甲基溴化铵(CTAB)乳状液,用电导法测定了含与不含添加剂(正已醇和水杨酸钠)条件下,乳状液富油相区不同时间的电导率.为了寻找乳状液的稳定性与电导率之间的关系,提出了富油相增比电导率的概念,并由增比电导率与时间的关系讨论了乳状液的稳定性.     

强碱三元驱油剂及结垢颗粒对乳状液稳定性的影响

针对强碱三元复合驱采出液乳化严重的问题,通过室内模拟方法对比研究了强碱三元驱油剂及结垢颗粒对乳状液稳定性的影响,并基于稳态浓相体积增比、油相含水率和水相含油量对数据进行了分析。结果表明:三元体系中NaOH质量分数从0.8%增加到1.2%,乳状液的稳定性降低,油滴的聚并速率常数增加、稳态浓相体积增比降低、油相含水率和水相含油量均降低;三元体系中表面活性剂质量分数从0.1%增加到0.4%,稳态浓相体积增比增加了2倍;增大三元体系溶液黏度,乳状液的稳定性提高;在三元体系中,SiO_2和FeS结垢颗粒质量浓度增加会促进乳状液的稳定性,而增加CaCO_3结垢颗粒的质量浓度会降低乳状液的稳定性。研究成果可以根据采出液中化学剂和结垢颗粒的质量浓度高低识别采出液乳状液稳定性,并采取有效的治理措施。     

电导率与O/W乳状液的稳定性

 测定了不同油相体积分数的O/W乳状液电导率，考察了油相体积分数、乳化条件、温度对O/W乳状液电导率的影响，研究了O/W乳状液电导率与其浓相体积变化分数、吸光度的关系。结果表明，对于较稳定的O/W乳状液，油相体积分数对O/W乳状液电导率有明显的影响，油相体积分数越大，电导率越小；反之，电导率越大。乳化条件越苛刻，电导率越小。温度越高，电导率越大。O/W乳状液电导率随时间变化曲线的斜率可以表征在O/W乳状液的破坏过程中，油珠上浮、聚集、聚并、油相体积分数变化的程度以及乳状液的稳定性。     

无机盐对石油磺酸钠乳状液的性能和微观状态的影响

通过观测乳状液的析水(油)率、电导率和破乳电压研究了无机盐对石油磺酸钠乳化白油和去离子水所形成的水包油乳状液性能的影响,并利用显微镜观察了乳状液微观状态的变化。结果表明,NaCl和KCl等一价无机盐在一定浓度内能增强乳状液的稳定性,使液滴粒径减小,分布更均匀,彼此间的连接更紧密;超过此浓度后不利于乳状液的稳定,但不会使其转相。高价无机盐会使乳状液转相为油包水型,金属离子半径越小,价态越高,引发转相所需的初始浓度越低;转相后的乳状液稳定性降低,液滴粒径增大,分布均匀程度变差,呈独立球形,稳定性按引发剂MgCl_2、AlCl_3、CrCl_3、CaCl_2、SrCl_2、BaCl_2、FeCl_3的顺序依次减弱。     

影响原油乳状液稳定性的因素研究

研究了室内制备油包水型原油乳状液的制备参数(转速、乳化时间)、含水率、水电导率以及温度等因素对原油乳状液稳定性的影响。结果表明,转速对原油乳状液的形成起决定性作用,转速为7000r/min,乳化时间为8min时形成了乳状液,而且转速越大、乳化时间越长,水滴粒径越小,粒径分布越均匀,原油乳状液越稳定;含水率越高,原油乳状液稳定性越差;原油乳状液电导率的大小取决于乳状液中水电导率的大小,能够反映原油乳状液的稳定性。温度升高,原油乳状液的稳定性降低。     

二元复合体系油水乳状液稳定性实验

通过测量模拟油水乳状液电导率的方法表征乳状液的稳定性,研究了十二烷基苯磺酸钠(SDBS)浓度、乙醇助剂浓度对O/W型和W/O型乳状液电导率变化的影响,探讨了二元复合体系中,聚合物对乳状液稳定性影响。结果表明,与传统的摇管看界面测量乳状液稳定性方法相比,测定电导率的方法能解决油水界面不清晰、读数不准确的问题;并发现SDBS浓度的增加,会使O/W型原油乳状液稳定性减小,但有利于W/O型乳状液的稳定;加入聚合物能增强O/W型乳状液稳定性,但将减弱W/O型乳状液稳定性。     

机械作用对强碱三元乳状液稳定性的影响

油田强碱三元体系采出液运移和输送过程中产生乳化作用,造成输送能耗增加、油水分离难度增加.以室内模拟油水机械乳化方法,研究了水油体积比、乳化速率和乳化时间对强碱三元乳化体系乳状液稳定性的影响,并基于油相含水率和水相含油量对试验数据进行了分析.结果表明:水油体积比从9:1降低到1:4,乳状液的稳定性增强;乳化速率从1000...     

原油复配破乳剂的配方设计

研究了水相pH值、非离子破乳剂和助剂对沙轻原油、阿曼原油、杰诺原油、胜利原油乳液稳定性的影响 ,考察了破乳剂与助剂的协同效应。结果表明 :沙轻原油在水相 pH =6～ 7时乳液的稳定性最差 ;破乳剂通过降低界面张力和使沥青质胶团向油相解缔而破坏乳液的稳定性 ;有机小分子助剂改变界面极性环境或增加芳香度使沥青质增溶而破坏乳液的稳定性 ,它们与破乳剂有很好的协同效应     

Stability of Water-in-Crude Oil Emulsions: Effect of Oil Aromaticity,Resins to Asphaltene Ratio,and pH of Water

Abstract

The formation of tight water-in-oil emulsions during production and transport of crude oils is a great problem challenging the petroleum industry. Tremendous research works are directed to understanding the mechanism of formation, stabilization, and controlling of oil field emulsions. This article presents experimental results of some of the factors controlling the formation and stabilization of water-in-crude oil emulsions. In this study, asphaltenes and resins separated from emulsion samples collected from Burgan oil field in Kuwait have been used to study emulsion stability. Model oils of resin to asphaltene ratio of 5:1 and toluene-heptane mixtures have been used to study the effect of oil aromaticity on emulsion stability. Results indicate that at low toluene content (below 20%) or high content (above 40%) less stable emulsions are formed. At a threshold value of 30% toluene, a very tight model oil emulsion is formed. The effect of resins to asphaltene (R/A) ratio on stability of model oil has also been investigated. Results reported in this paper show that as the R/A increases the emulsions become less stable. The effect of pH on stability of model oil emulsion made of 50/50 heptane-toluene mixture having R/A ratio of 5:1 have been studied. Experimental results revealed that as the pH of the aqueous phase of model oil increased from 2 to 10, the emulsion became less stable. At high pH, the asphaltene particles are subjected to complete ionization leading to destruction of the water-oil interface and eventually breakdown of the emulsion.     

Stability of oil-in-water emulsions by SDS compound

Abstract

Surfactants are often required to reduce emulsion viscosity and heavy-oil flow resistance in pipelines, thereby forming a stable oil-in-water emulsion under shear stress. This study aimed to quantitatively discuss and analyze the stability of oil-in-water emulsions and characterize them through the initial viscosity change rate K. The value of K was obtained based on the oil-rich-phase viscosity curves of oil-in-water emulsions comprising sodium dodecyl sulfate (SDS), heavy oil, and water at different time points. Results showed that a smaller K corresponded to a more stable emulsion according to analysis of the effect of the compound system on emulsion stability and the synergistic mechanism. We then combined with 1-pentanol and octyldecyl glucoside (APG0810) with SDS. Results showed that the K values of the emulsions decreased from 19.457 to 6.284, and 19.457 to 5.834, respectively, after mixing 6% 1-pentanol and 0.4% APG, respectively, with 0.14% SDS. Then, 0.14% SDS was compared with 1.2% a mass fraction of each of the three additives to form a compound system, and the K values were found to follow the trend K_{1-pentanol/SDS} > K_APG/SDS. Thus, the stability of APG/SDS oil-in-water emulsion was better than that of 1-pentanol/SDS emulsion.     

造纸废液用于稠油降粘的初步研究

在注蒸汽开采稠油时常用掺热稀油降粘的方法延长蒸汽吞吐周期。本文探索了用造纸度液代替热稀油降粘的可能性。室内研究结果表明:将造纸废液用水稀释至10％—30％,按稠油与稀释液之比为60:40或50:50加入稠油中,可得到良好的降粘效果又不致影响电脱水工序。     

A novel investigation of effect of nonionic surfactant on wettability alteration and viscosity variation of emulsion for oil recovery

When the fluid inside of the reservoir has a high viscosity due to having a lower mobile ratio, therefore, water flooding is not suitable for oil recovery, and a system with a higher viscosity should be used. The emulsions have more viscosity, so in this system, in order to stabilize and optimize the viscosity of the system, chemical additives such as polymer and surfactant are used. These chemical additives damage the reservoir and the environment and lose their stability under high temperature, therefore, in this study; the emulsions stabilized with nanoparticles have been studied, and the effect of nonionic surfactant on wettability alteration was investigated, and various factors on the viscosity of this system have been determined.     

Ti改性骨架Ni催化乙腈液相加氢制乙胺

 研究了以改性骨架Ni催化剂液相催化乙腈加氢制备乙胺的工艺. 考察了Ti改性骨架Ni催化剂中Ti/Ni摩尔比, 反应体系中NaOH助剂的加入量和加氢反应温度、H₂压力、搅拌速率等因素对改性骨架Ni催化乙腈液相加氢制备乙胺反应的影响. 确定了Ni改性骨架Ni催化剂最适宜的Ti/Ni摩尔比和催化乙腈加氢制备乙胺的最佳工艺条件, 并初步探讨了Ti改性骨架Ni催化剂对乙腈催化加氢反应的影响机制. 结果表明, 在Ti/Ni摩尔比为0.012的改性骨架Ni催化剂作用下, 以水作溶剂, NaOH助剂的加入量为0.20g/l, 在反应温度333～343K、H₂压力1.0MPa、搅拌速率1000r/min的反应条件下, 乙腈的转化率达到100%, 乙胺的选择性可达75.6%. 此外, 还根据Ti改性骨架Ni催化剂液相催化乙腈加氢反应中重复使用的情况考察了其稳定性.     

Characterization of Physico-Chemical Properties of Oil/Water Systems: Interfacial Behavior Prediction

The tractability of petroleum is intimately related to the type of emulsion that is formed during its production. The characteristics of water/oil and oil/water emulsions depend on some factors such as the density and the composition of the oil. In this work, the properties of oils coming from the Campos Basin, Brazil, were evaluated by means of water-in-oil emulsion physico-chemical, interfacial, and characterization tests. Such properties have been correlated with the tractability of the petroleum in order to establish a behavior prediction method based on the properties of such petroleum. The main tool used in this work was the chemiometry technique. Through this method, it was possible to conclude that density, viscosity, surface tension, and nickel content were the properties that influenced the separation of the oils. Density, pour point, initial temperature of crystal formation (TIAC), characterization factor, and nitrogen content were the properties that influenced the diameter of the emulsion drops.