不同链长石油羧酸盐和不同碳数纯烃之间的界面张力

实验考察了由平均碳数为23．16、26．01、28．70的大庆原油馏分油经氧化、皂化制备的石油羧酸盐A、B、C与正庚烷、正十二烷、正十六烷之间45℃下的界面张力(动态界面张力稳定值)与水相盐度的关系。石油羧酸盐在水相中的质量浓度为1g／L。对于每一种烷烃，随着石油羧酸盐平均碳数增大，产生超低界面张力所需的盐度范围缩小。最低界面张力对应的盐度(最佳盐度)减小；而对于每一种石油羧酸盐，随着烷烃碳数增大，产生超低界面张力的盐度范围扩大。最佳盐度增大但相互间差别减小。从达到的界面张力值、盐度范围和盐度值来看，对于正庚烷、正十二烷、正十六烷。较适宜的表面活性剂分别是石油羧酸盐A、B、C。研究结果表明，在超低界面张力体系中，石油羧酸盐的平均碳数与烷烃碳数之间、烷烃碳数与盐度之间有一定的对应关系；在石油羧酸盐的应用中，原油的EACN值和油藏矿化度都必须考虑。图6参5。     

大庆原油馏分复合体系界面活性及乳化性研究

为考察原油成分对复合体系界面活性的影响，将原油通过实沸点蒸馏法切割成不同的馏分，对各饱民三元体系的动态界面张力进行了测定。还探讨了馏分油的乳化液稳定性及重组分对尼液稳定性的影响。研究结果表明，与三元体系的界面张力，轻馏分最低瞬时其次是重组分，再次是不旨点依次升高的中间馏分；在轻饱 加入重组分可以进一步降低界面张力；馏分油与二元（Ａ／Ｓ）体系形成的乳状液，其稳定性随饱沸点升高而降低，加入重组分可提高     

模拟二元复合驱采出液稳定性影响因素研究

二元复合驱是中高渗透油藏提高采收率的主要技术之一。为了研究聚表二元驱对乳状液稳定性的影响,选取含聚表水与模拟油组成油水界面体系,测试了油水界面张力、界面剪切黏度等参数,并结合乳状液静置脱水效果,分析聚表二元驱对油水采出液稳定性的作用机理。采用含聚合物和表面活性剂的水相与模拟油配制成模拟油采出液,用于测试不同聚合物及表面活性剂浓度对界面张力的影响。界面张力结果表明:聚表二元驱成分能够显著增大油水乳状液的稳定性,但聚合物与表面活性剂在界面活性上存在明显差异;界面剪切黏度的影响因素主要为聚合物;静置脱水实验表明,影响油水乳状液稳定性的主要因素为表面活性剂。这与过去的观点存在矛盾,即认为界面剪切黏度是影响乳状液稳定性的关键。因此本研究认为存在其他因素影响乳状液稳定性。     

甜菜碱活性剂驱油体系对油水界面张力的影响

通过研究作为驱油表面活性剂的甜菜碱污水溶液与大庆油田第一采油厂脱水原油之间的界面张力,探讨了活性剂浓度、碱的种类和浓度、牺牲剂等因素对体系界面张力的影响,同时研究了岩心静态吸附前后和采出液界面张力值的变化情况.实验结果表明:碱对界面张力的影响较大,该体系表面活性剂中无需加碱;牺牲剂加入到此类表面活性剂的体系中能够很好地发挥作用.     

糖基表面活性剂对埃洛石纳米流体驱油的影响

针对纳米流体在驱油体系中存在的分散稳定性的问题,研究了糖基阳非离子表面活性剂(GDBB)对埃洛石纳米管(HNTs)分散稳定性的影响,并考察了GDBB/HNTs纳米颗粒的乳化,降低界面张力及改变油湿玻璃片(岩石模型)润湿性能力。研究表明,GDBB通过静电作用吸附在HNTs表面使其疏水性增大,分散稳定性提高,具有乳化,润湿反转,降低界面张力能力。配比为m(GDBB)∶m(HNTs)=1∶1时,改性埃洛石纳米流体可提高原油采收率最大,高达25.2%。     

INFLUENCING FACTORS OF THE INTERFACIAL TENSION.OF BINARY COMPOUND FLOODING WITHOUT ALKALINE

二元复合体系的界面张力对提高驱油效率具有重要作用.通过研究无碱二元复合体系与大庆油田萨中开发区脱水原油之间的界面张力,探讨了注入水质、聚合物相对分子质量、聚合物质量浓度、表面活性剂类型、表面活性剂质量分数和原油组分等因素对二元复合体系界面张力的影响,同时给出了不同二元复合体系瞬时界面张力值的变化情况.实验结果表明:表面活性剂类型和质量分数对界面张力的影响较大,油田注入水质、聚合物相对分子质量和原油组分分别对瞬时界面张力值和平衡界面张力值存在不同程度的影响,聚合物质量浓度对界面张力的影响不大.实验结果对于明确形成超低界面张力的条件具有一定意义.     

复合表面活性剂驱油剂的性能评价

表面活性剂驱油已成为现阶段提高驱油效果最常用的方法。本实验主要评价几种驱油用表面活性剂降低油水界面张力的能力,考察溶液浓度对其界面性能的影响。同时,以析液半衰期测定为评价指标,对其乳化能力进行考察。通过对表观黏度的测定,评价几种驱油用聚合物稳定性。最终评价聚合物与表面活性剂复配之后对界面张力产生的影响。     

影响旋转滴界面张力测定因素的研究

使用旋转滴界面张力测定仪对长2原油、甲苯、正己烷、环己烷与不同浓度的表面活性剂十二烷基苯磺酸钠(SDBS)和十二烷基磺酸钠(SDS)体系的界面张力进行了测定。讨论了仪器的平衡时间、转速、工作温度等因素对界面张力测量值的影响。同时分析了不同油相对界面张力的影响。结果表明:各体系平衡时间选择在20~30min之间时界面张力测定值准确度较高;在满足L/D≥4的测定要求后继续增大转速会使测量值偏大;仪器工作温度的提高则导致界面张力测定值逐渐减小。     

表活剂类型对旋转滴界面张力测定的影响研究

使用旋转滴界面张力测定仪对长2原油、甲苯、正己烷、环己烷与不同浓度的两种类型的表面活性剂十二烷基硫酸钠(SLS)和十四烷基三甲基溴化铵(TTAB)体系的界面张力进行了测定。讨论了仪器的平衡时间、转速、工作温度等因素对界面张力测量值的影响。同时分析了不同油相对界面张力的影响。结果表明:各体系平衡时间选择在20~30min之间时界面张力测定值准确度较高;在满足L/D≥4的测定要求后继续增大转速会使测量值偏大;仪器工作温度的提高则导致界面张力测定值逐渐减小。     

三元复合驱采出水性质及稳定性机理研究

通过对大庆油田二厂南四-8(弱碱)和四厂三元-6(强碱)三元复合驱采出水水质、含油量-沉降时间关系和驱油剂-油滴粒径关系等进行测定分析,得到了三元水的基本性质及驱油剂对其稳定性的影响。碱对三元水稳定性影响具有双重性,随着碱量增大,小粒径油滴分布增多,少部分油滴粒径已达到胶体粒径范围,碱量增到一定值,采出水油滴会发生聚并而分离;表面活性剂降低油水界面张力,促进油滴分散,其长链分子间存在斥力,可阻碍油滴聚并;聚合物增加采出水黏弹性,增大油滴聚并阻力,减小上浮速度。碱和表面活性剂的协同作用可使原油中的活性物质发生皂化,同时碱在一定程度上促进了聚合物自身水解,增大界面活性,使得采出水稳定性增强。     

Influence of surfactants used in surfactant-polymer flooding on the stability of Gudong crude oil emulsion

The influences of an anionic-nonionic composite surfactant and petroleum sulfonate, used in surfactant-polymer flooding in Shengli Gudong oilfield, East China, on the interfacial properties of Gudong crude model oil and synthetic formation water was studied by measuring interfacial tension, interfacial viscoelasticity and Zeta potential. The influence of the surfactants on the stability of Gudong water-in-oil (W/O) and oil-in-water (O/W) emulsions was evaluated by separating water from the W/O emulsion and residual oil in the aqueous phase of the O/W emulsion respectively. The results showed that the two kinds of surfactants, namely anionic-nonionic composite surfactant and petroleum sulfonate, are both able to decrease the interfacial tension between the oil phase and the aqueous phase and increase the surface potential of the oil droplets dispersed in the O/W emulsion, which can enhance the stability of the W/O and O/W crude oil emulsions. Compared with petroleum sulfonate, the anionic-nonionic composite surfactant is more interfacially active and able to enhance the strength of the interfacial film between oil and water, hence enhance the stability of the W/O and O/W emulsions more effectively.     

用动界面张力方法研究原油/盐水界面的性质Ⅰ.原油天然表面活性剂和破乳剂的竞争吸附现象

测定了原油 /盐水的动界面张力 ,比较了在无破乳剂存在时几种体系的动界面张力曲线。证明了原油天然表面活性剂分子渐渐扩散吸附到原油 /盐水界面上 ,当体系中有破乳剂存在时 ,破乳剂分子以竞争的方式扩散吸附到原油 /盐水界面上。用动界面张力方法研究原油天然表面活性剂和破乳剂在原油 /盐水界面的吸附速率对研究原油乳状液的破乳机理和优化破乳条件十分重要。     

Gemini Surfactant as a New “Green” Demulsifier for Treating Oilfield Emulsions

Abstract

Surface tension and interfacial tension (IFT) were the key factors asso- ciated with the stability of crude oil emulsion. Investigation of interfacial tension behavior related with the demulsification of crude oil emulsions can have a great impact on the development of crude oil demulsification processes and products. This article presents the surface and interface behaviors of Gemini surfactants (12-2-12, (12)-2-(12), (14)-2-(14)). The results indicated that (12)-2-(12) could exhibit higher surface and interface active properties. The demulsification efficiency and related factors were also discussed. It showed that as an environmentally friendly and safer demulsifier, Gemini surfactant could exhibit better demulsification efficiency.     

EFFECT OF ASPHALTENE AND RESINS ON THE STABILITY OF WATER-IN-WAXY OIL EMULSIONS

Asphaltene, resins and paraffin waxes, their mutual interactions and their influence on the stability of water-in-oil emulsions have been studied. 20 wt % paraffin wax dissolved in decalin was used to model the waxy crude oil. Asphaltene and resins separated from a crude oil were used to stabilize the water-in-oil emulsions. Synthetic formation water was utilized as the aqueous phase of the emulsion. The emulsion stability increased with increasing the concentration of asphaltene with a subsequent decrease in the average particle size distribution of the emulsion. Resins alone are not capable of stabilizing the emulsion, however, in the presence of asphaltene they form very stable emulsions. Dynamic viscosity and pour point measurements provided evidence for resins-paraffin waxes interactions. Asphaltene in the form of solid aggregates form suitable nuclei for the wax crystallites to build over with a mechanism similar to that of paraffin wax crystal-modifiers. As asphaltene are polar in nature they are derived at the oil/water interface which was proved by the ability of asphaltene to reduce oil/water interfacial tension. Consequently, nucleation of the wax crystallites by asphaltene and resins at the interface will add to the thickness of the oil-water interfacial film and hence increase the stability of the emulsion.     

EFFECT OF ASPHALTENE AND RESINS ON THE STABILITY OF WATER-IN-WAXY OIL EMULSIONS

ABSTRACT

Asphaltene, resins and paraffin waxes, their mutual interactions and their influence on the stability of water-in-oil emulsions have been studied. 20 wt % paraffin wax dissolved in decalin was used to model the waxy crude oil. Asphaltene and resins separated from a crude oil were used to stabilize the water-in-oil emulsions. Synthetic formation water was utilized as the aqueous phase of the emulsion. The emulsion stability increased with increasing the concentration of asphaltene with a subsequent decrease in the average particle size distribution of the emulsion. Resins alone are not capable of stabilizing the emulsion, however, in the presence of asphaltene they form very stable emulsions. Dynamic viscosity and pour point measurements provided evidence for resins-paraffin waxes interactions. Asphaltene in the form of solid aggregates form suitable nuclei for the wax crystallites to build over with a mechanism similar to that of paraffin wax crystal-modifiers. As asphaltene are polar in nature they are derived at the oil/water interface which was proved by the ability of asphaltene to reduce oil/water interfacial tension. Consequently, nucleation of the wax crystallites by asphaltene and resins at the interface will add to the thickness of the oil-water interfacial film and hence increase the stability of the emulsion.     

原油乳状液稳定性研究 Ⅱ.原油成分对原油乳状液稳定性的影响

原血成分的表面活性物质及其细微固体颗粒,在油水界面上相互作用是原油乳状液其有稳定性的主要原因。本文采用简单的方法将原油中众多的物质分成两大类,并根椐它们单独时或混合后对癸烷/水乳状液稳定性作用的特征,将其分别称为原油乳化剂和原油破乳剂。试验表明,原油乳状液稳定性的高低主要取决于所含的这两大类物质的多少和相对比例,其相对重要性可由界面张力定性地反映出来;并且由原油/水界面张力的大小可以定性地评估原油乳状液的稳定性。     

油／水界面张力快速测定方法的研究及应用

为了简便、快速、可靠地测定表面活性剂对原油/水界面张力的影响,室内根据滴体积法原理建立了一套快速测定油/水界面张力的装置,并对该装置测定结果的影响因素、平行性及可靠性进行了检验。结果表明,滴落速度对测定结果的影响较大,滴落速度应≥5秒/滴。该方法平行性较好,相对误差小于2%,苯/水体系测定误差小于1%,可以用于测定油/水体系界面张力。室内用该方法考察了生物表面活性剂、鼠李糖脂工业品、化学防蜡剂加量对原油/水界面张力的影响,得到3种药剂的最佳加药量分别为5%、4%、4%,相同加量下的药剂界面活性顺序为:化学防蜡剂>生物表面活性剂>鼠李糖脂工业品。图1表5参4     

STUDY ON THE MICROEMULSION BEHAVIOR OF THE OXIDIZED PARAFFIN WAX

The interfacial tension between paraffin wax and water, as well as oxidized paraffin wax and water has been studied and the results showed that the interfacial tension between oxidized paraffin wax and water decreased obviously after paraffin wax was oxidized to proper degree. Meanwhile the pseudo-ternary phase diagram of the oxidized paraffin wax/surfactants/water system has been determined. It was confirmed that using a single surfactant A or cosurfactant B couldn't prepare oxidized paraffin wax microemulsion and the cosurfactant A/surfactant B mass ratio k_m has a proper range and an optimized value to produce the oxidized paraffin wax microemulsion, moreover, the microemulsion particle distribution was analyzed.     

聚合物、表面活性剂两元驱界面性质对乳状液稳定性影响

应用电导率仪测定了聚丙烯酰胺与表面活性剂溶液的电导率,考查了聚合物与表面活性剂的相互作用.应用界面张力仪、表面粘弹性仪和Zeta电位仪测定了油水界面性质,研究了界面性质对乳状液稳定性的影响.结果表明,聚合物与表面活性剂复合能够形成稳定的聚集体,较小的界面张力、较大的界面剪切粘度值以及较高的Zeta电位有利于乳状液的稳定存在.