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。     

两种石油磺酸盐与不同原油间界面张力的探讨

考察了不同体系与不同原油间的界面张力变化.主要讨论了Na2CO3质量浓度、体系组成和原油种类对界面张力的影响.结果表明:单独使用石油磺酸盐的体系降低界面张力的能力较低,且达到超低界面张力的Na2SCO3质量浓度范围较窄.1#石油磺酸盐/异丙醇/磺酸盐表面活性剂DS复配体系(F3)降低大庆原油界面张力的能力最优,且达到超低界面张力的碱范围较宽.2#石油磺酸盐复配前后与大庆原油、大港原油间界面张力的变化不太显著,界面张力在10-3mN/m-1～10-2mN/m-1.     

二元复合驱中表面活性剂的优选与评价

表面活性剂的优选与评价是二元复合驱研究中很重要的一部分。使用美国Texas-500型界面张力仪测试油水界面张力,优选出符合标准的s5表面活性剂。同时,测试不同浓度的表面活性剂对聚合物溶液粘度的影响,发现随着表面活性剂浓度的增加,聚合物溶液的粘度会有一定程度的增加。研究结果表明,在合适的浓度条件下,优选出的s5表面活性剂不仅能将油水界面张力降低至超低界面张力水平,又可以使聚合物溶液的粘度保持较高水平,可以应用于二元复合驱。     

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     

温度和盐离子对表面活性剂溶液与原油之间界面张力的影响规律研究

为了研究油藏条件对表面活性剂性质的影响,本文用TH5000旋转滴超低界面张力仪研究了不同温度和不同盐离子浓度下,表面活性剂溶液与原油之间的油水界面张力。结果说明,本文研究的三种表面活性剂中,温度越高,阴离子表面活性剂H102与原油之间的界面张力越低,非离子表面活性剂W201与原油之间的界面张力先降低后增加,Gemini季铵盐型表面活性剂G101与原油之间的界面张力基本不变;矿化度越高,三种表面活性剂与原油之间的界面张力越低,而且,Ca~(2+)、Mg~(2+)等高价离子的加入使油水界面张力更易降低。比较来看,G101具有耐温、耐盐的良好性能。     

三次采油用表面活性剂结构对油/水界面性能的影响

测定了几种不同分子结构的磺酸盐类阴离子表面活性剂、两性表面活性剂和非离子表面活性剂水溶液与国内某油田原油间的界面张力。结果表明:磺酸盐类表面活性剂降低油水界面张力的能力相对较高,且磺酸盐的烷链长度、芳环种类对界面张力的影响较大,调整磺酸盐的分子结构可以使油水界面张力降低到10~(-2)mN/m数量级;醇/酚醚类非离子表面活性剂以及两性表面活性剂仅能使油水界面张力降低至0.1 mN/m~10 mN/m数量级。     

甜菜碱表面活性剂及其聚表二元体系性能评价

使用界面张力仪上的旋转滴法,测定了甜菜碱表面活性剂及其无碱二元复合体系对大庆一厂和六厂油水界面张力的影响因素,研究了甜菜碱表面活性剂浓度对动态界面张力的影响。同时还对该甜菜碱表面活性剂二元体系的乳化性能及稳定性能进行了评价。实验结果显示:该甜菜碱表面活性剂可在较宽浓度范围内(0.025%~0.03%)与一厂、六厂原油形成10~(-3)m N·m~(-1)数量级超低界面张力。浓度高的甜菜碱表面活性剂,虽然有利于降低瞬时界面张力,但不利于保持界面张力。甜菜碱表面活性剂二元体系具有较好的粘度稳定性和界面张力稳定性,二元体系粘度保留率大于90%。     

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。     

重烷基苯磺酸盐弱碱化复配研究

以强碱重烷基苯磺酸盐为基础原料,加入混合剂A进行复配得到弱碱表面活性剂,研究了弱碱化下界面张力的情况,室内评价结果表明,这种表面活性剂具有良好的界面活性,配制的复合体系在较宽的表面活性剂浓度和碱浓度范围可与原油形成10^-3mN／m数量级的超低界面张力。     

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。     

A New Series of Double-Chain Single-Head Sulfobetaine Surfactants Derived from 1,3-Dialkyl Glyceryl Ether for Reducing Crude Oil/Water Interfacial Tension

A new series of sulfobetaine surfactants with double-chain single-head structure were derived from 1,3-dialkyl glyceryl ethers and their performances in reducing Daqing crude oil/connate water interfacial tension (IFT) in the absence of alkali were studied. With a large hydrophilic head group and double hydrophobic chains, these surfactants are efficient at reducing crude oil/connate water IFT. Those with didecyl and dioctyl are good hydrophobic surfactants that can reduce Daqing crude oil/connate water to ultra-low IFT by mixing with a small molar fraction of various conventional single-chain hydrophilic surfactants, such as α-olefin sulfonates, dodecyl polyoxyethylene (10) ether, and cetyl dimethyl hydroxypropyl sulfobetaine. The asymmetric double-chain sulfobetaine derived from 1-decyl-3-hexyl glyceryl ether can reduce Daqing crude oil/connate water IFT to ultra-low solely over a wide concentration range (0.03–10 mM or 0.0017–0.58 wt.%), which allows for use of an individual surfactant instead of mixed surfactants to avoid chromatographic separation in the reservoir. In addition, formulations rich in sulfobetaine surfactants show low adsorption on sandstone, keeping the negatively charged solid surface water-wet, and forming crude oil-in-water emulsions. These new sulfobetaine surfactants are, therefore, good candidates for surfactant-polymer flooding free of alkali.     

A new zwitterionic surfactant with high interfacial activity and high salt tolerance derived from methyl oleate through an eco-friendly aryl-introducing method

Surfactants, that can reduce the interfacial tension between crude oil and formation water to ultra-low, are needed in tertiary oil recovery. A bio-based zwitterionic surfactant, N-phenylpropanaldehyde epoxy acetal octadecanoicamido propyl-N, N-dimethyl hydroxy sulfonate (PADS), was derived from methyl oleate. In the process of synthesizing PADS, a new reactive site was introduced by epoxidizing methyl oleate and then the benzene ring was introduced by acetalization, which was a greener new method of introducing benzene ring into hydrophobic chains of surfactants. PADS was identified by ESI-MS and NMR, and its interfacial activity was measured by interfacial tensiometer. The results showed that PADS possessed excellent interfacial activity and potential for low-dose application. Under alkali-free conditions, it could reduce the interfacial tension between crude oil and simulated formation water to ultra-low in a wide concentration range (0.005–3 g/L). In addition, although the NaCl concentration was 230 g/L in the system, PADS still had good interfacial activity and could maintain ultra-low oil–water interfacial tension. The protocol of epoxidation and acetalization provides a new feasible path to preparing bio-based surfactants with high interfacial activity.     

超低界面张力石油磺酸盐复配驱油剂研究

通过室内实验研究了溶液质量分数、矿化度对石油磺酸盐溶液与大庆L区块原油的界面张力的影响,并将不同类型表面活性剂分别与石油磺酸盐复配,筛选出能够使油/水界面张力降至超低(10-3 mN/m数量级)的最优增效组合,以取代ASP复合驱中所加的碱.实验结果表明,在矿化度为6 000～10 000 mg/L,钙、镁离子质量浓度不超过20 mg/L时,石油磺酸盐表面活性剂有良好的抗盐性,可使油/水界面张力达到超低.在实验所选的不同类型表面活性剂中,石油磺酸盐与甜菜碱型表面活性剂复配起到明显的增效作用,特别是与椰油酰丙基磺基甜菜碱复配增效作用尤为显著,且两者复配的浓度范围较宽,油/水界面张力易达到超低.     

Novel alkyl methylnaphthalene sulfonate surfactants: A good candidate for enhanced oil recovery

The surface tensions of various surfactant aqueous solution and the dynamic interfacial tensions between the Shengli oil field of China crude oil and the solution of novel surfactants, a series of single-component alkylmethylnaphthalene sulfonates (AMNS) including various the length of alkyl chains (hexyl, octyl, decyl, dodecyl and tetradecyl, developed in our laboratory), were measured. It is found that synthesized surfactants exhibited great capability and efficiency of lowering the solution surface tension. The critical micelle concentrations, CMC were: 6.1–0.018×10⁻³ mol L⁻¹, and the surface tensions at CMC, γ_CMC were: 28.27–35.06 mN m⁻¹. It is also found that the added surfactants are greatly effective in reducing the interfacial tensions and can reduce the tensions of oil–water interface to ultra-low, even 10⁻⁶ mN m⁻¹ at very low surfactant concentration without alkali. The addition of salt, sodium chloride, results in more effectiveness of surfactant in reducing interfacial tension and shows that there exist obviously both synergism and antagonism between the surfactant and inorganic salt. All of the synthesized surfactants, except for hexyl methylnaphthalene sulfonate, can reduce the interfacial tension to ultra-low at an optimum surfactant concentration and salinity. Especially Tetradec-MNS surfactant is most efficient on lowering interfacial tension between oil and water without alkaline and the other additives at a 0.002 mass% of very low surfactant concentration. Both chromatogram separation of flooding and breakage of stratum are avoided effectively, in addition to the less expensive cost for enhanced oil recovery, and therefore it is a good candidate for enhanced oil recovery.     

耐盐型双子表面活性剂驱油体系研究

对一种新型双子表面活性剂GA12-4-12进行了研究。该表面活性剂在矿化度为2.5×10^5mg/L、氯化钙浓度为1.5×10^4mg/L的水溶液中表现出良好的表面活性,其临界胶束浓度为538.6mg/L。GA12-4-12溶液与稀油间的油水界面张力随着盐含量的增加（60～250g/L）而降低。在高矿化度模拟地层水条件下,GA12-4-12及其与聚合物复合体系SP的油水动态界面张力均能达到超低值（10^-3mN/m）。进行模拟驱油实验表明,GA12-4-12与SP复合体系提高水驱采收率分别为6.25%、10.67%。     

耐盐高稳泡超低界面张力泡沫体系研究

对28种表面活性剂进行了泡沫综合性能评价和油水界面张力测试,并通过不同表面活性剂之间的复配和配方的优化,筛选出高稳泡超低界面张力的泡沫体系。结果表明,当FC-06、5#和DS10复配表面活性剂的质量分数为0.4%,配比为2∶1∶3时,最大起泡体积为500 mL,半衰期为28.8 min,平衡时的油水界面张力为8.0×10~(-3) mN/m。泡沫体系性能评价结果表明,在40 000 mg/L的矿化度条件以下,泡沫体系均能保持高稳泡时间和超低界面张力,具有较强的耐盐性。     

Gemini表面活性剂/醇/正辛烷/盐水体系微乳液的研究

以壬基酚为原料在催化剂存在下与二溴烷烃作用生成双醚,然后磺化,合成了一类Gemini阴离子表面活性剂,用悬滴法测定了其油水界面张力,结果表明,Gemini表面活性剂可使油水界面张力降低到 10-3mN/m。研究了Gemini表面活性剂 /醇 /正辛烷 /盐水体系的微乳液相行为,通过拟三元相图的方法确定了助表面活性剂醇的种类,实验结果表明,链长的比链短的醇具有更好的助活作用。通过正交实验方法得到了形成中相微乳液的最佳组成:w(GeminiD) =0 1%;w(n C6H13OH) =4 0%;w(NaCl) =1 5%。     

Effects of temperature and time on interfacial tension behavior between heavy oils and alkaline solutions

Heavy oils contain significantly more acidic components than conventional crude oils. Upon contact with aqueous alkaline solutions, water-soluble surfactants are formed in-situ at the interface. These surfactants have the ability to reduce the oil/water interfacial tension to ultra-low values. This work studies the significant effects of time and temperature on the interfacial tension between alkaline solutions and two Canadian heavy oils (Lloydminster and Cold Lake). The results obtained indicate that the time period during which interfacial tension remains ultra-low is just as important as the magnitude of the minimum attainable interfacial tension in determining the potential success of an alkaline flooding process in the field.     

表面活性剂在油水界面的吸附行为

简要介绍了液液界面张力的由来,以及降低油水界面张力在石油工业中的意义;重点介绍了影响表面活性剂降低油水界面张力的因素,包括水相、油相、表面活性剂及使用条件。概括总结了类V型、类L型、类倒L型动态油水界面张力曲线,讨论了不同形状动态界面张力曲线与表面活性剂在油水界面处吸附、解吸行为的关系;简述了界面张力曲线形态间的相互转变。