Gemini表面活性剂微乳液相行为的影响因素研究

研究了Gemini表面活性剂微乳液的界面相行为,考察了中间联接基团长度、表面活性剂和助表面活性剂的配比、醇链长和烷烃链长对相图的影响。结果表明：短链联接基团较易形成单相微乳液,表面活性剂用量较少且有较高的含水量;随着烷烃链长增加,形成O/W区域所需表面活性剂含量增加,且区域面积在逐渐减小;醇链长改变时,沿着油-（S＋A）轴都能形成W/O型微乳液。     

Stabilization of natural gas foams using different surfactants at high pressure and high temperature conditions

Natural gas foam can be used for mobility control and channel blocking during natural gas injection for enhanced oil recovery, in which stable foams need to be used at high reservoir temperature, high pressure and high water salinity conditions in field applications. In this study, the performance of methane (CH₄) foams stabilized by different types of surfactants was tested using a high pressure and high temperature foam meter for surfactant screening and selection, including anionic surfactant (sodium dodecyl sulfate), non-anionic surfactant (alkyl polyglycoside), zwitterionic surfactant (dodecyl dimethyl betaine) and cationic surfactant (dodecyl trimethyl ammonium chloride), and the results show that CH₄-SDS foam has much better performance than that of the other three surfactants. The influences of gas types (CH₄, N₂, and CO₂), surfactant concentration, temperature (up to 110°C), pressure (up to 12.0 MPa), and the presence of polymers as foam stabilizer on foam performance was also evaluated using SDS surfactant. The experimental results show that the stability of CH₄ foam is better than that of CO₂ foam, while N₂ foam is the most stable, and CO₂ foam has the largest foam volume, which can be attributed to the strong interactions between CO₂ molecules with H₂O. The foaming ability and foam stability increase with the increase of the SDS concentration up to 1.0 wt% (0.035 mol/L), but a further increase of the surfactant concentration has a negative effect. The high temperature can greatly reduce the stability of CH₄-SDS foam, while the foaming ability and foam stability can be significantly enhanced at high pressure. The addition of a small amount of polyacrylamide as a foam stabilizer can significantly increase the viscosity of the bulk solution and improve the foam stability, and the higher the molecular weight of the polymer, the higher viscosity of the foam liquid film, the better foam performance.     

疏水缔合聚合物的合成及溶液性质研究

Acrylamide/2-acrylamido alkane sulfonic acid hydrophobic associating copolymers were synthesized by micellar copolymerization. Effects of hydrophobe content, polymer concentration, salinity and surfactant on rheological behavior of copolymers were investigated and the conformation of polymers in solution was studied by means of environmental scanning electronic microscopy and dynamic light scattering. The experimental results showed that in the dilute regime the hydrophobic parts could interact intramolecularly, while in the regime where the polymer concentration was higher than the critical association concentration, intermolecular hydrophobic association became predominant. Within the limit of the solubility, the critical association concentration of the polymer decreased with the increase of the salinity. The experimental results of the solution conformation indicated the presence of the three-dimensional network structure in deionized water and the size of the mesh in the network varied with the polymer concentration. In NaG1 solution, above the critical association concentration, an increase in polymer concentration enhanced the intermolecular association and also enlarged the hydrodynamic radius. It would result in the imorovement of the thickening power of polvmers.     

空气泡沫驱驱油机理与实验研究

针对传统聚合物驱、三元复合驱等驱油体系在中后期油田开采中采油效率不高的问题,提出一种高效空气泡沫驱驱油技术。为验证高效泡沫驱的驱油效果,以延长油田1#地质条件为背景,探讨不同起泡剂浓度、矿化度下对空气泡沫驱的性能影响,从而筛选出空气泡沫驱的最优综合性能,通过驱替实验,对高效泡沫驱驱油机理进行观察。最后通过封堵能力评价验证了空气泡沫驱的性能与驱油机理。     

Colloid‐Enhanced Ultrafiltration of Chlorophenols in Wastewater: Part IV. Effect of Added Salt on the Surfactant Leakage in Surfactant Solutions and Surfactant–Polymer Mixtures

Abstract

The critical aggregation concentration (cac) in surfactant–polymer mixtures approximates a lower limit to the surfactant concentration in the permeate (surfactant leakage) in polyelectrolyte micellar‐enhanced ultrafiltration. Here, the cac was measured at different salinities by using surface tension measurements. It was found that the cac increases slightly with the addition of simple salt, then the cac value decreases at higher salt concentration. The critical micelle concentration (CMC), which approximates surfactant leakage in micellar systems (no polymer), decreases monotonically with increasing salinity for ionic surfactants. The surfactant leakage in colloid‐enhanced ultrafiltration (CEUF) processes is investigated by using a dialysis method in the presence of three phenolic solutes with various degrees of chlorination: 2‐monochlorophenol (MCP), 2,4‐dichlorophenol (DCP), and 2,4,6‐trichlorophenol (TCP). Cetylpyridinium chloride (CPC) or n‐hexadecylpyridinium chloride is used as a cationic surfactant; and sodium poly(styrenesulfonate) (PSS) is used as an anionic polyelectrolyte. The effect of salinity and type of colloid is focused on here. In the absence of added salt, the cac can be over an order of magnitude less than the CMC, as can be surfactant leakage with added polymer. The added salt reduces the surfactant leakage in the micellar solution due to CMC reduction in the presence of electrolyte. In the surfactant–polymer mixture, the surfactant leakage is dramatically affected by salinity.     

二元复合驱表面活性剂界面张力研究

研究了二元驱用植物改性羧酸盐表面活性剂SNHD与原油间的动态界面张力,并探讨了聚合物、矿化度、pH值以及时间对界面张力的影响。结果表明SNHD与原油的界面张力能达到超低值;聚合物对界面张力影响不大;矿化度对低活性剂浓度体系界面张力的影响较大,随矿化度增加,界面张力减小;体系的最佳pH值约为7。     

一种阴／非离子表面活性剂的稠油降黏性能评价

合成了一种阴／非离子表面活性剂,考察了油水比、含水率、温度、表面活性剂浓度、矿化度等对降黏效果的影响,确定了最佳条件为：油水比为7：3,温度为50℃,表面活性剂浓度为2500mg／L,抗盐能力可达12000mg／L。在此条件下,对稠油的降黏率达90％以上。     

无碱二元复合体系界面张力影响因素研究

探讨了了表面活性剂浓度、聚合物浓度、温度、二价离子、矿化度等因素对表面活性剂体系界面特性的影响。评价该新型无碱二元复合体系界面张力能够达到10-3数量级的油藏应用条件。研究结果表明:二元复合体系在很低的活性剂浓度(0.005%)与原油间的界面张力达到超低;聚合物浓度对二元体系与原油间的界面张力影响较大;配制二元体系用水中矿化度、二价离子对复合体系界面张力影响不大,该活性剂能够适合于较高矿化度或者二价离子浓度含量较高的油层;温度对二元复合体系的界面张力基本无影响,在45~80℃范围区间内均可以达到超低。     

Solubilization and fluorescence behavior of petroleum sulfonate containing microemulsions

The effects of various oils and alcohols on the brine solubilization and fluorescence behavior of oil-external microemulsions were investigated. At a critical electrolyte concentration, referred to as optimal salinity, the brine solubilization capacity of microemulsions containing petroleum sulfonate is maximum for C₆–C₁₀ oils and C₄–C₇ alcohols. Moreover, at this salinity, the fluorescence intensity was found to be maximal. As the chain length of oil is increased, the optimal salinity increased for all the alcohols studied. However, the increase in optimal salinity was much greater for water-soluble alcohols than for pentanol, hexanol or heptanol. The brine solubilization limit decreased as the oil chain length increased for microemulsions containing n-butanol and iso-butanol. The solubilization behavior is explained in terms of solubility of alcohols in various phases of microemulsions and the ability of the aqueous phase to solubilize surfactant molecules from the interface. The fluorescence behavior is explained by higher surface charge density around the water droplet near optimal salinity. A simple correlation is given between the solubilization and fluorescence behavior of microemulsions that is independent of type and chain length of the alcohols or hydrocarbons.     

新型两性表面活性剂的驱油体系界面特性变化规律研究

随着三次采油技术的不断发展,复合体系的表面活性性能和含量是在提高采收率技术研究中日趋重要。本文针对新型两性表面活性剂一元及聚合物/表面活性剂二元体系同油的界面特性展开了研究。结果表明：一元体系中表面活性剂质量浓度越高,界面张力达到稳定所需时间越短;随着体系中表面活性剂质量浓度的增加,稳定界面张力值越低。聚合物对两性表面活性剂同模拟油之间的界面张力有影响,且有利于体系同模拟油间的界面张力的降低;但界面张力并不是随着聚合物质量浓度的增加一直单纯降低,当质量浓度为1.0g/L时界面张力最低。     

Acidic Heavy Oil Recovery Using a New Formulated Surfactant Accompanying Alkali–Polymer in High Salinity Brines

The strength of a newly formulated surfactant with an alkali and polymer (AS/ASP) to improve an acidic heavy oil recovery was laboratory evaluated by various flooding experiments. The comparative role of the parameters like chemical nature, surface wettability, salinity, temperature and injection scheme were explored at high temperature and pressure on Berea sandstone rocks. According to the results the anionic surfactant is capable of providing proper oil displacement under high salinity conditions around 15 wt%. Continuous monitoring of differential pressure response and effluents’ state clearly represented the formation of an emulsified oil in high saline solutions with both alkali and surfactant. Adding sodium metaborate to the surfactant solution reduced the interfacial tension (IFT) to ultra low values and decreased the surfactant emulsion generation capability at higher salinities. Besides, adding Flopaam AN113SH to the chemical slug increased the residual oil removal owing to lower mobility ratios. So, while high capillary number and an emulsion phase were generated by the A/S slug phases, adding polymer could further enhance the performance of these chemicals. On the other hand, chemical flooding through the oil-wet medium resulted in shorter break through time, lower differential pressure, finer emulsion formation, and lower oil recovery in comparison to the similar water-wet cases.     

Experimental investigation and modelling of CO2-foam flow in heavy oil systems

In this work, the C_14-16 alpha olefin sulphonate (AOS) surfactant, octylphenol ethoxylate (TX-100), and methyl bis[Ethyl(Tallowate)]-2-hydroxyethyl ammonium methyl sulphate (VT-90) surfactant were selected as representatives of anionic, nonionic, and cationic surfactant to stabilize foam. The effects of surfactant concentration and gas/liquid injection rates on foam performance were examined by performing a series of oil-free foam flow tests by injecting CO₂ and a foaming surfactant simultaneously into sandpacks. Foam flooding was conducted as a tertiary enhanced oil recovery (EOR) method after conventional water flooding and surfactant flooding. Furthermore, a new method was proposed to determine the residual oil saturation. The foam stability in the presence and absence of heavy oil was studied by a comparative evaluation of the mobility reduction factor (F_MR) in both cases. The foam fractional flow modelling by Dholkawala and Sarma^[36] was modified based on experimental results obtained in this study. The range of the ratio of two important model parameters (C_g/C_c) at various foam qualities was determined and could be used for large-scale predictions. The results showed that during the oil-free foam displacement experiments higher foam apparent viscosities () were attained at lower gas flow rates and the maximum was attained at a total gas and liquid injection rate of 0.25 cm³/min with a gas fractional flow ratio of 0.8 for the foam in the absence of oil. The presence of oil reduced the foam mobility reduction factors (F_MR) to different degrees with F_MR-_{without oil} / F_MR-_{with oil} ranging from 4.25–13.69, indicating that the oil had a detrimental effect on the foam texture. The foam flooding successfully produced an additional 8.1–21.52 % of OOIP, which can be attributed to the combined effect of increasing the pressure gradient and oil transporting mechanisms.     

Development of water‐blown bio‐based thermoplastic polyurethane foams using bio‐derived chain extender

Water‐blown bio‐based thermoplastic polyurethane (TPU) formulations were developed to fulfill the requirements of the reactive rotational molding/foaming process. They were prepared using synthetic and bio‐based chain extenders. Foams were prepared by stirring polyether polyol (macrodiol), chain extender (diol), surfactant (silicone oil), chemical blowing agent (distilled water), catalyst, and diisocyanate. The concentration of chain extender, blowing agent, and surfactant were varied and their effects on foaming kinetics, physical, mechanical, and morphological properties of foams were investigated. Density, compressive strength, and modulus of foams decrease with increasing blowing agent concentration and increase with increasing chain extender concentration, but are not significantly affected by changes in surfactant concentration. The foam glass‐transition temperatures increase with increasing blowing agent and chain extender concentrations. The foam cell size slightly increases with increasing blowing agent content and decreases upon surfactant addition (without any dependence on concentration), whereas chain extender concentration has no effect on cell size. Bio‐based 1,3‐propanediol can be used successfully for the preparation TPU foams without sacrificing any properties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

稠油开采用耐高温抗盐乳化降粘剂

介绍了耐高温抗盐乳化降粘剂S -5 ,该剂是一种磺酸盐型聚合物表面活性剂 ,可用于乳化降粘法开采稠油 ;评定了该降粘剂在高温处理前后的降粘效果以及该降粘剂在硬水中乳化稠油的能力 ;讨论了降粘剂相对分子质量对其降粘效果的影响     

泌304区块稠油乳化降粘剂的筛选与评价

针对泌阳凹陷南部陡坡带泌304区块地下原油粘度高的特点,本文通过化学降粘方法,筛选出能够和稠油乳化并形成水包油（O／W）型乳化液的表面活性剂,优选表面活性剂浓度,研究了温度、矿化度、油水比等对乳状液粘度的影响。     

Effects of Triglyceride Molecular Structure on Optimum Formulation of Surfactant-Oil-Water Systems

The effects of triglyceride molecular structure on the formulation of surfactant-oil-water systems were evaluated by comparing the optimum salinity and the dynamic interfacial tensions. The systems contained an anionic extended surfactant and triglyceride oils with different chain lengths and degrees of unsaturation. The results show that with an increasing degree of oil unsaturation (more double bonds), surfactant interactions with the triglycerides become weaker, thus requiring higher optimum salinity and resulting in higher interfacial tension values. Effects of ester groups and chain length of triglycerides are also discussed and the EACN of the triglycerides and vegetable oils studied are reported.     

含氟丙烯酸酯共聚物涂膜表面润湿性的研究

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酸β–羟乙酯(HEMA)、(甲基)丙烯酸高级酯(AAs)、含氟(甲基)丙烯酸酯(Fs)等单体为原料,HDI三聚体为固化剂,通过改变共聚物组成、氟碳链长、(甲基)丙烯酸高级酯烷烃链长等因素,合成了一系列的含氟丙烯酸酯共聚物。采用水、煤油和液压油接触角以及水滴滚动距离,表征了共聚物涂膜的表面润湿性,并探讨了其影响因素。结果表明,共聚物组成和结构、烷烃链长对水的接触角影响不大,而对水的滚动性能具有较大影响;氟碳链长以及氟单体的添加方式对油水接触角和水的滚动性能有较大影响;烷烃侧链的柔顺性对油的接触角影响较大,而对水几乎没有影响。     

Phase diagram, viscosity and conductivity of α-sulfonate methyl esters derived from palm stearin/1-butanol/alkane/water systems

Phase diagrams of sodium salt α-sulfonate methyl esters derived from palm stearin (α-SMEPS)/1-butanol/alkane/water systems were constructed at 30.0±0.1°C. The presence and changes in the isotropic region of the quaternary mixtures of surfactant, co-surfactant, alkane (oil) and water were mapped with different oil compound (different hydrocarbon chain lengths). An attempt to elucidate the self-association behavior of α-SMEPS in the presence of butanol as co-surfactant and the effect of different alkane chain lengths was conducted by studying the viscosity and electrical conductivity behavior. Preliminary investigation suggested that the formation of oil-in-water (o/w) microemulsion, bicontinuous structure and water-in-oil microemulsion were based on the composition of mixtures in the isotropic region.     

自生CO2泡沫驱油可行性研究

针对低矿化度,中低温的稠油油藏,开展自生CO<,2>泡沫驱油的可行性研究.通过大量的实验,筛选出了稳定高效、经济可行的生气体系以及性能优越的起泡剂和稳泡剂,得到了优良的自生泡沫体系配方.考察了温度对自生泡沫体系起泡性和稳泡性的影响,并对自生CO<,2>泡沫体系的粘度的长期稳定性和油水界面张力性质进行了测定.实验结果表明...     

Synergistic Effects between Anionic and Sulfobetaine Surfactants for Stabilization of Foams Tolerant to Crude Oil in Foam Flooding

In foam flooding, foams stabilized by conventional surfactants are usually unstable in contacting with crude oil, which behaves as a strong defoaming agent. In this article, synergistic effects between different surfactants were utilized to improve foam stability against crude oil. Targeted to reservoir conditions of Daqing crude oil field, China (45 °C, salinity of 6778 mg L⁻¹, pH = 8–9), foams stabilized by typical anionic surfactants fatty alcohol polyoxyethylene ether sulfate (AES) and sodium dodecyl sulfate (SDS) show low composite foam index (200–500 L s) and low oil tolerance index (0.1–0.2). However, the foam stability can be significantly improved by mixing the anionic surfactant with a sulfobetaine surfactant, which behaves as a foam stabilizer increasing the half-life of foams, and those with longer alkyl chain behave better. As an example, by mixing AES and SDS with hexadecyl dimethyl hydroxypropyl sulfobetaine (C₁₆HSB) at a molar fraction of 0.2 (referring to total surfactant, not including water), the maximum composite foaming index and oil tolerance index can be increased to 3000/5000 L s and 1.0/4.0, respectively, at a total concentration between 3 and 5 mM. The attractive interaction between the different surfactants in a mixed monolayer as reflected by the negative β^s parameter is responsible for the enhancement of the foam stabilization, which resulted in lower interfacial tensions and therefore negative enter (E), spreading (S), and bridging (B) coefficients of the oil. The oil is then emulsified as tiny droplets dispersed in lamellae, giving very stable pseudoemulsion films inhibiting rupture of the bubble films. This made it possible to utilize typical conventional anionic surfactants as foaming agents in foam flooding.