三元复合驱体系粘度影响规律研究

为了增加三元复合驱协同效应驱油体系在油层中的有效驱油运移距离并提高最终驱油效果,本文通过室内实验和数值模拟方法,分别研究不同浓度的碱和表面活性剂在含有聚合物的溶液里面,两者对体系粘度的影响。结果表明,表面活性剂浓度对粘度影响很小;碱浓度对粘度影响在碱浓度小于0.5%之前十分明显,但大于0.5%后趋于稳定。     

表面活性剂/聚合物二元复合体系超低界面张力的影响因素研究

为了研究二元复合体系超低界面张力的影响因素,通过物理实验方法分别测得不同条件下界面张力的变化规律。结果表明,石油磺酸盐阴离子表面活性剂在一定的浓度范围内可以达到超低界面张力;加入聚合物的表面活性剂所形成的二元复合体系可以有效地延长表面活性剂到达平衡界面张力值所需的时间;分子吸附理论可以解释同浓度表面活性剂的界面张力先降低到最低再升高的原因,同时也可以解释高浓度表面活性剂能够在较短时间内达到超低界面张力值的原因。     

碱/烷基硫酸盐、烷基磺酸盐体系与原油间的动态界面张力的研究

合成了一系列高纯度的表面活性剂。在碱溶液中添加单一的表面活性剂 ,简化了驱油体系。考察了表面活性剂的结构、浓度与动态界面张力的关系。结果表明 ,只有当表面活性剂在两相的分配系数适当时 ,才具有较高的活性     

混合羧酸盐复合驱油体系的研究(Ⅰ)--针对高酸值原油

针对胜利油田孤东采油厂高酸值原油，以自制的天然混合羧酸盐SDC-3为表面活性剂，通过相态研究方法，得出最佳配方体系。它与原油形成的中相乳状液达到French四级标准，即含有质量分数为90％原油的棕色乳状液。该体系与原油界面张力值的数量级可达10^-3mN.m^-1，室内平均模拟驱油效率为22．6％，其驱油成本为108．6元／t。最后结合现场使用需求开展驱油体系溶液制备过程中搅拌速度、温度、水质和贮存时间等因素对其性质影响的研究以及小试产品和工业产品的性能比较，以便满足配方在实际应用中的要求。     

复合体系与原油多次乳化过程中油水界面张力变化规律

为进一步了解三元复合驱驱油机理,深入研究复合驱油过程中原油与复合体系两相流体在地层中多次接触乳化过程中界面张力变化规律,在地层温度45℃条件下,开展了一系列不同含水率下强碱三元复合体系与大庆原油多次乳化实验。结果表明,复合体系与原油多次接触乳化后,具有较强地保持超低界面张力的能力;水相分别与上相油和原油间界面张力能够达到超低的乳化次数随含水增加而增加;乳化次数相同时,水相与原油间界面张力低于其与上相油间界面张力;随着乳化次数增加,三元体系与原油间最低界面张力值有先下降后升高的趋势;无论是与原油间界面张力还是与上相油间界面张力达到超低时的乳化次数二元体系都多于三元体系,说明复合驱注入段塞优化时可适当考虑二元体系。     

复合体系与原油多次乳化过程中油水界面张力变化规律

为进一步了解三元复合驱驱油机理,深入研究复合驱油过程中原油与复合体系两相流体在地层中多次接触乳化过程中界面张力变化规律,在地层温度45℃条件下,开展了一系列不同含水率下强碱三元复合体系与大庆原油多次乳化实验。结果表明,复合体系与原油多次接触乳化后,具有较强地保持超低界面张力的能力;水相分别与上相油和原油间界面张力能够达到超低的乳化次数随含水增加而增加;乳化次数相同时,水相与原油间界面张力低于其与上相油间界面张力;随着乳化次数增加,三元体系与原油间最低界面张力值有先下降后升高的趋势;无论是与原油间界面张力还是与上相油间界面张力达到超低时的乳化次数二元体系都多于三元体系,说明复合驱注入段塞优化时可适当考虑二元体系。     

聚合物驱后二元复合体系驱油效果研究

主要通过室内物理实验,分析了聚合物/表面活性剂二元复合体系的粘弹性和界面张力对采收率的影响,并对聚合物驱后聚合物/表面活性剂二元复合体系驱油效果进行了研究。     

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。     

甜菜碱体系对玉门油田界面张力影响规律研究

研究了新型甜菜碱表面活性剂复配体系对玉门油田油水界面张力的影响情况。通过使用Texas-500型界面张力仪,利用旋转滴法测定了甜菜碱表面活性剂的水溶液与玉门油田脱水原油之间的界面张力,讨论了活性剂浓度、碱的浓度、矿化度对甜菜碱复配体系油水界面张力的影响。实验结果表明:该甜菜碱活性剂与其它助剂有很好的协同作用,选择合适的助剂与其复配可以很大程度上减少该甜菜碱活性剂的用量,降低经济成本。碱对界面张力的影响较大,当碱浓度为0.8%时,可以使该复配体系与玉门原油油水界面张力达到10-3 m N/m。     

天然混合羧酸盐ASP复合驱油体系的研究

Orthogonal-test-design method has been used to determine the optimal formula by phase behavior and interfacial tension studies, respectively. The effect of each component of two alkaline/surfactant/polymer flooding systems on interfacial tension is discussed, in which a low-price natural mixed carboxylate (SDC) is used as the major surfactant. The results indicate that the optimal composition is SDC (0.5%), alkaline NaHCO3/Na2CO3 with mass ratio of 1 (1.0%), and hydrolyzed polyacrylamide(0.1%). In the coreflood experiment, their oil recovery is increased by about 25.2% and 26.8% original oil in place, respectively.     

高分子表面活性剂与原油形成超低界面张力的研究

对ＡＭ－ＡＯＰ_ｎ和ＣＭＣ－ＡＲ１２ＥＯ_ｎ两类高分子表面活性剂与原油形成超低界面张力的研究结果表明,加碱复配后,ＡＭ－ ＡＯＰ_ｎ和 ＣＭＣ－ ＡＲ_１２ＥＯ_ｎ与大庆原油的界面张力分别可达 ２．６ ×１０~（－３）ｍＮ／ｍ和 ３．２ｘ １０~（－３）ｍＮ／ｍ。显微观察表明,碱使胶束解缔是界面张力降低的主要因素。     

油水界面行为对原油乳状液破乳的影响

测定了在破乳剂作用下原油乳状液的油水界面张力,界面膜强度及破乳脱水率,结果表明,界面张力的变化与体系的初始状态有关,它反映了破乳剂分子在界面上的吸附程度,界面张力的高低不能作为破乳剂破乳效果的依据。具有较强的油水界面吸附能力而又能显著降低界面膜强度的破乳剂分子,能达到较好的破乳效果。     

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.     

Interfacial properties of cationic and anionic Gemini surfactant mixtures

The possibility and the prospect of cationic/anionic (“catanionic”) surfactant mixtures based on sulfonate Gemini surfactant (SGS) and bisquaternary ammonium salt (BQAS) in the field of enhanced oil recovery was investigated. The critical micelle concentration (CMC) of SGS/BQAS surfactant mixtures was 5.0 × 10⁻⁶ mol/L, 1–2 orders of magnitude lower than neat BQAS or SGS. A solution of either neat SGS or BQAS, could not reach an ultra-low interfacial tension (IFT); but 1:1 mol/mol mixtures of SGS/BQAS reduced the IFT to 1.0 × 10⁻³ mN/m at 100 mg/L. For the studied surfactant concentrations, all mixtures exhibited the lowest IFT when the molar fraction of SGS among the surfactant equaled 0.5, indicating optimal conditions for interfacial activity. The IFT between the 1:1 mol/mol SGS/BQAS mixtures and crude oil decreased and then increased with the NaCl and CaCl₂ concentrations. When the total surfactant concentration was above 50 mg/L, the IFT of SGS/BQAS mixtures was below 0.01 mN/m at the studied NaCl concentrations. Adding inorganic salt reduced the charges of hydrophilic head groups, thereby making the interfacial arrangement more compact. At the NaCl concentration was above 40,000 mg/L, surfactant molecules moved from the liquid–liquid interface to the oil phase, thus resulting in low interfacial activity. In addition, inorganic salts decreased the attractive interactions of the SGS/BQAS micelles that form in water, decreasing the apparent hydrodynamic radius (D_{H, app}) of surfactant aggregates. When the total concentration of surfactants was above 50 mg/L, the IFT between the SGS/BQAS mixtures and crude oil decreased first and then increased with time. At different surfactant concentrations, the IFT of the SGS/BQAS mixtures attained the lowest values at different times. A high surfactant concentration helped surfactant molecules diffuse from the water phase to the interfacial layer, rapidly reducing the IFT. In conclusion, the cationic-anionic Gemini surfactant mixtures exhibit superior interfacial activity, which may promote the application of Gemini surfactant.     

伊朗轻质原油减渣馏分油水界面张力的研究

The vacuum residual from Iranian Light crude oil are separated into a series of 16 narrow fractions according to the molecular weight by the supercritical fluid extraction and fractional (SFEF) technology. The chemical element and the UV spectrum of each fraction are analyzed. The effects of several factors on the interfacial tension are investigated, which are the fraction concentration in oil phase, the ratio of oil component, the salts dissolved in the water phase and the pH value. The interfacial tension decreases rapidly as the concentration of the residual fraction in the oil increases, showing a higher interfacial activity of the fraction. The interfacial tension changes, as the amount of absorption or the state of the fractions in the interface changes resulting from different ratios of oil, different kinds or concentrations of salts in water, and different pH values. It is concluded that the intrfacial tension changes regularly, corresponding to the regular molecular parameters of the vacuum residual fractions.     

驱油阴/两性表面活性剂复配体系协同效应研究

针对某油藏A区块,利用阴离子/两性表面活性剂的协同作用,进而达到油水超低界面张力,且两性表面活性剂十二烷基甜菜碱在浓度为0.1%~0.5%的范围内,降低油水界面张力的效果达到10~(-2) mN/m数量级,在加入阴离子表面活性剂的条件下,复配体系可以使油水界面张力达到超低界面张力。通过探讨表面活性剂的总浓度以及复配比对油水界面张力的影响,最终得到阴离子/两性表面活性剂复配体系可在较高矿化度和较低的浓度(0.4%)范围内达到10~(-3) mN/m的超低界面张力,并在此基础上对两者的协同作用进行分析。