超低界面张力重烷基苯磺酸盐复配驱油剂研究

研究了不同浓度的重烷基苯磺酸盐对长庆油田S区块的原油界面张力的影响,将重烷基苯磺酸盐与阴离子和甜菜碱表面活性剂复配,使油/水界面张力降至超低(10^(-3) mN/m数量级),并研究复配体系的乳化、自发乳化、耐温耐盐以及稳定性。结果表明,重烷基苯磺酸盐的复配体系具有优秀的降低界面张力的能力,尤其是与石油磺酸盐和椰油酰胺丙基羟基磺基甜菜碱(CHSB),能够大幅提升界面张力性能,同时两种复配体系具有优异的耐温耐盐稳定性。     

生物与化学表面活性剂复配体系的研究

通过生物表面活性剂(DSB)与化学表面活性剂重烷基苯磺酸盐ZW1、重烷基苯磺酸盐ZW2及α 烯烃磺酸盐(XT)的复配,对复配前后的三元复合驱油体系界面张力进行了研究。结果表明,生物表面活性剂DSB与重烷基苯磺酸盐ZW1和α 烯烃磺酸盐XT复配后可以显著降低三元体系的界面张力,与ZW2复配也可达到降低成本的目的。     

重烷基苯磺酸盐微乳体系的相行为

能使大庆原油／地层水界面张力降至超低５的重烷基苯磺酸盐（中试产品）在无醇、１０ｇＮａＣｌ／Ｌ条件下,地壬烷产生最低界面张力。在４５℃下,以行烷为油相,重烷基苯磺酸盐为表面活性剂,仲丁醇为助表面活性剂,可以与盐水形成微乳体系。对重烷基苯磺酸盐浓度０．１５ｍｏｌ／Ｌ（水相浓度）,仲丁醇／重烷基苯磺酸盐ｍｏｌ比＝１８．５：１,水／油体系比＝１：１的微乳体系,增加盐度可导致ＷｉｎｓｏｒＩ→ＷｉｎｓｏｒⅡ宫     

石油羧酸盐与重烷基苯磺酸盐复配体系性能研究

通过石油羧酸盐与重烷基苯磺酸盐复配后的体系在弱碱（Na₂CO₃）条件下分别与大庆采油三厂和大庆采油六厂的油水发生作用,对体系的界面张力性能和模拟驱油效率进行检测,同时进行了体系界面张力稳定性试验。结果表明,该复配体系具有优良的界面张力,模拟驱油效率达20%左右,稳定性良好,并且可大幅度提高原油采收率。     

复配表面活性剂对复合驱油体系性能影响研究

通过对α-烯烃磺酸盐、重烷基苯磺酸盐、石油磺酸盐和复配型等4种表面活性剂配制复合驱油体系的界面张力和黏度性质进行评价,重点对复配型表面活性剂配制复合驱油体系的界面张力和驱油效果进行了系统评价。结果表明,当碱的质量分数为0.3%~0.9%、表面活性剂的质量分数为0.1%~0.3%时,复配型表面活性剂配制复合驱油体系的界面张力可以达到10-3mN/m数量级,且具有达到超低界面张力所需质量分数低和范围宽等特点。物理模拟实验表明,复配型表面活性剂配制三元复合体系的增油效果较单一类型表面活性剂配制三元复合体系的好,采收率增加1.46%(体积分数)。在此基础上,对复配表面活性剂超低界面张力的作用机理进行了理论分析。     

重烷基苯磺酸活性物含量的影响因素分析

活性物含量是重烷基苯磺酸的一个主要质量指标,对磺酸盐的界面张力性能有着重要影响。通过对影响重烷基苯磺酸活性物含量各种因素的分析,研究提高磺酸活性物含量的方法,这对提高重烷基苯磺酸的质量和磺酸盐的界面张力性能有着积极的指导意义。     

多管膜式磺化技术在油田表活剂生产中的应用

重烷基苯磺酸盐是三元复合驱的主要活性剂,是利用石油化工装置的副产物重烷基苯作为主要原料进行深度加工的油田专用化学剂。它与聚合物复配,形成超低界面张力,提高驱油效果,提高采收率,增加原油产量,是一种比较现实的理想的油田驱油助剂。选用国内外最先进的膜式磺化技术,对组成比较复杂的重烷基苯原料可以有效地控制磺化产品的质量。大庆油田6万吨/年重烷基苯磺酸盐工程投产成功是多管膜式磺化技术在重烷基苯磺酸盐工业化生产的成功应用,在国内首次实现了油田用表面活性剂工业化生产。     

两种油溶性磺酸盐与重烷基苯磺酸盐复配体系的界面性能

以十二烷为油相,比较了二烷基苯磺酸盐（DAS）与α-烯烃磺酸钠（C2024AOS）两种不同结构的油溶性表面活性剂与重烷基苯磺酸盐（HABS）复配体系的界面张力.结果表明,具有苯环结构的DAS和直链型C2024AOS本身界面张力均较高.但与HABS/LAS二元体系复配之后,DAS与HABS之间在降低界面张力方面存在明显的协同效应（固定HABS与DAS质量比为3∶1,LAS含量为20％时,DAS/HABS/LAS三元体系界面张力可以达到3.28×10-3 mN/m;固定LAS含量为30％,DAS与HABS质量比为1∶1时,界面张力可以达到1.85×10-3 mN/m）,而C2024AOS与HABS之间不存在明显的协同效应.     

复配表面活性剂对三元复合体系界面张力的影响

本文通过对重烷基苯磺酸盐与石油磺酸盐表面活性剂复配进行筛选,优选出三元复配体系油水界面张力最好时的表面活性剂复配比例为重烷基苯磺酸盐:石油磺酸盐为1:3。同时,对该复配比例下的强碱三元复合体系进行界面活性图扫描,结果表明:复配三元体系在低碱区的界面活性较好,体系界面张力稳定。     

石油磺酸盐复合体系界面张力影响因素研究

在三元复合体系中油水形成的界面张力值对驱油效率影响很大,界面张力值越低驱油作用越好。本文以石油磺酸盐、聚丙烯酰胺和碳酸钠复合驱油体系在大庆油田下的界面张力为研究对象,采用旋滴法测量,研究了组分含量、污水矿化度及金属离子浓度对复合体系界面张力的影响,确定了经济的浓度范围。结果表明,石油磺酸盐浓度为0. 025%～0. 4%时该三元体系界面张力均可达到超低10-3m N/m数量级;聚丙烯酰胺浓度过高会影响复合体系界面张力值,适宜浓度为500～1000 ppm;碳酸钠浓度的增加有利于降低复合体系界面张力值;在钙镁离子浓度低于1500 mg/L、钠离子低于6000 mg/L矿化度的模拟污水中,该复合体系界面张力仍可达到超低值。     

重烷基苯磺酸盐驱油体系配方设计

文章研究了重烷基苯磺酸盐(HABS)/QK-25原油间的界面张力(IFT)。探讨了HABS种类、复配比例和浓度,醇种类和含量,Na2CO3含量和非离子表面活性剂TX-10含量对IFT的影响。结果表明,当金桐2#/南京1#=5∶5时,体系界面张力最低;最优醇类为正丁醇,但醇种类和含量对界面张力影响不显著;TX-10含量、Na2CO3含量和HABS浓度对体系界面张力的影响依次减小。     

TRANSIENT INTERFACIAL TENSION BEHAVIOR BETWEEN ACIDIC OILS AND ALKALINE SOLUTIONS

A study of the dynamic interfacial tension behavior of reacting acidic oil/alkaline solutions has been conducted for both an artificially acidified synthetic oil and a real crude oil for four different alkalis at various concentrations. The IFT values between a 10 mM acidified synthetic oil and various 25 mM alkaline solutions, before the minimum IFT value was reached, were found to be in the descending order: KOH, NaOH, Na₂SiO₃ and LiOH. The corresponding IFT values between diluted Lloydminster heavy crude oil and the same alkaline solutions, again before the minimum was reached, were found to be in the descending order: LiOH, NaOH, Na₂SiO₃ and KOH. The crude oil exhibited lower minimum IFT values against alkaline solutions than the synthetic acidified oil. The general trend of decreasing IFT towards a minimum value followed by an increase in IFT thereafter was noted for all solutions tested.     

Study on the Adaptability of Alkanolamide (LDEA) Lowering Oil/Water Interfacial Tension to Different Crude Oils

In order to investigate the high interfacial activity and fair oil phase adaptability of alkanolamide, “1:1” type lauric acid diethanolamide impurities (LDEA) were synthesized and purified by the column chromatography method to obtain dodecanoic acid diethanolamide (C₁₂DEA), ester mixture, etc. The exact structures of these compounds were further confirmed by IR, gas chromatogrph with mass spectroscopy (GC–MS), and NMR. The influence of each component on the interfacial tension of oil/water (IFT) was studied by systematic quantitative analysis. The results showed that (i) the strength of each system to reduce oil/water IFT is C₁₂DEA /DEA ≈ LDEA > C₁₂DEA/DEA/ESTER > C₁₂DEA/NaOH > C₁₂DEA > C₁₂DEA/ESTER > DEA. This indicates that LDEA contributes to the reduction of the oil/water IFT and the enhanced adaptability of crude oil in this order: DEA > > ESTER; (ii) when the IFT of the LDEA/DEA system reached an ultralow value, the minimum content of DEA in the system was 1%, and the maximum ester content was less than 5% when the LDEA/DEA/ESTER system reached the ultralow IFT; (iii) the possible mechanism of effect of LDEA components on the IFT and oil phase adaptability was proposed as the synergistic process among the hydrogen bonding, alkali effect, and interface self-assembly of molecules in the interfacial layer. The contribution of these three factors were hydrogen bonding > alkali effect > interface self-assembly.     

表面活性剂同系物体系对原油界面张力的影响

分别从表面活性剂的亲油性和亲水性的二种性能 ,研究了复配型表面活性剂的性能及规律。在表面活性剂同系物复配的研究中 ,得出相对分子质量分布窄的表面活性剂不能与原油形成低的界面张力 ,但两种以上相对分子质量分布窄的表面活性剂按一定比例混合后 ,则可以与大庆原油形成超低界面张力。形成超低界面张力的表面活性剂平均当量范围为 410～ 430 ,相对分子质量、碱浓度和界面张力三者之间有一定规律 ,即表面活性剂平均相对分子质量增加 ,界面张力曲线向低浓度碱方向移动 ;平均相对分子质量降低 ,界面张力曲线向高浓度碱方向移动。相对分子质量分布是影响界面张力的又一因素 ,表面活性剂相对分子质量分布、原油中的碳数分布和界面张力可能存在某种特定联系。支链对降低界面张力方面比直链有更好的效果 ,表面活性剂相对分子质量越高 ,则油砂对其吸附量越大     

DYNAMIC INTERFACIAL TENSION IN HEXADECANE/WATER SYSTEMS CONTAINING READY-MADE AND IN-SITU-FORMED SURFACTANTS

Dynamic interfacial tension (IFT) between two immiscible liquids has been investigated by the method of drop volume tensiometry. Hexadecane and water were employed for the measurements. In the case of the pure oil-water system, it was found that with hexadecane as the drop phase the IFT was very close to the published value (53.5 mN/m). When water acted as the drop phase the apparent IFT was about 20% higher, and a correction method was developed to account for the different geometry of droplet formation. A similar effect was observed when a surface active additive was present in either one or both phases. The effects of ready-made surfactants and their in-situ-formed equivalents were examined. It was found that both decreased the IFT between the two phases, but the in-situ-formed surfactant was more effective in that respect, It was also found that the IFT between acidic hexadecane and NaOH solution increased when ready-made surfactant was added to the alkaline solution. Addition of salt (NaCl) produced the expected decrease in IFT while the effect of added NaOH appeared to be more complex.     

Interfacial tension of marine lipids in contact with high pressure carbon dioxide

Interfacial tension (IFT) of fish oil triglycerides (TG) and fatty acid ethyl esters (FAEE) in contact with carbon dioxide (CO₂) was measured according to the pendant drop method at 40, 55 and 70 °C and pressures up to 25 MPa. The IFT of both TG and FAEE decreased substantially with CO₂ pressure. The IFT of FAEE vanished at elevated pressures, whereas that of TG decreased to a fairly constant level of about 2 mN/m. The IFT was correlated using a model taking into account the density, pressure and temperature of CO₂, thereby facilitating the calculation of the ideal pendant drop volume as well as the surface excess concentration of CO₂. In the pressure range studied, the pendant drop volume for FAEE decreased with pressure, whereas for TG it increased at elevated presssures due to the predominant effect of buoyancy. Furthermore, the change in IFT over time was determined at 55 °C for TG in contact with CO₂ at pressures up to 11.4 MPa showing a decrease of IFT over time at low pressures, whereas at higher pressures it remained nearly constant. IFT influences drop formation as well as the disintegration of falling films thereby affecting the performance of separation processes.     

Surfactant Enhanced Oil Recovery in a High Temperature and High Salinity Carbonate Reservoir

The goal of this work was to find an effective surfactant system for enhanced oil recovery after water injection substituting for oil at a vuggy fractured reservoir with a high temperature and high salinity (220,000 mg/L). Four types of surfactants with concentrations (less than 0.2 %) were screened. Washing oil experiments were conducted in Amott cells. A surfactant system was established by mixing a surfactant with best ultimate recovery and one with best recovery rate. The optimized surfactant system could recover 50 % of remaining oil. To study the mechanism of enhanced oil recovery after water injection substituting oil, interfacial tension (IFT) and contact angle were measured. Experimental results showed that surfactants with good washing ability had low IFT, but surfactants with low IFT may not have a good washing ability. IFT had no obvious relationship with the increased oil recovery or washing ability. The optimized system could not alter carbonate to decrease the oil‐wetting capability. Though octadecyl trimethyl ammonium chloride had a good ability wet the carbonate with water, it could not recover much oil. Therefore, except for interfacial tension and wettability alteration, there must be other parameters dominating oil recovery after water injection substituting for oil.     

Diesel Oil Removal by Froth Flotation Under Low Interfacial Tension Conditions I: Foam Characteristics,and Equilibration Time

Abstract

Froth flotation is a surfactant‐based separation process which is suitable for treating dilute wastewaters. To achieve high performance for the froth flotation operation, the combination of an ultra‐low interfacial tension (IFT) between excess oil and excess water phases, high foam production rates, and high stability of the foam produced, must be attained. To obtain the ultra‐low interfacial tensions, a Winsor Type III or middle phase microemulsion has to be formed. In this study, branched alcohol propoxylate sulfate sodium salt with 14–15 carbon number and 4 PO groups (Alfoterra 145–4PO) was used to form microemulsions with diesel oil. From the results of this work, an increase in surfactant concentration decreased the IFT, and increased foam stability. To obtain the minimum IFT in the region of a Winsor Type III microemulsion, the addition of 5 wt.% NaCl was needed. However, this optimum salinity does not result in effective froth flotation due to poor foam characteristics. The results indicate that both the IFT and the foam characteristics should be optimized to achieve high efficiency of oil removal in a froth flotation operation. Unlike the previously‐studied ethylbenzene system, agitation of the solution before introduction into the flotation column yielded the lowest diesel oil removal efficiency because of the poor foam characteristics compared to either unagitated systems or systems allowed to equilibrate for one month.     

Changes in thermal properties of crude oil asphaltenes induced by NaOH treatment

In this study, an asphaltic Turkish crude oil was treated with alkali solution (NaOH) at different concentrations to simulate an alkali EOR technique. IFT (interfacial tension) measurements were carried out by ring method and the yields of asphaltene is precipitated after the process. Thermal properties of these asphaltenes were investigated by thermal analysis methods (thermogravimetry, TG/DTG and differential scanning calorimeter, DSC) to infer the possible changes in the asphaltene molecules and their behavior during refinery or fuel purposes.