【作者】 纪永强；

【导师】 郑利强；

【作者基本信息】 山东大学 ， 物理化学， 2008， 硕士

【摘要】 论文前两章讨论研究了阴离子表面活性剂蠕虫状胶束的流变性质。表面活性剂聚集体的流变性质与体系微观结构及内部基团间的相互作用有直接关系，在表面活性剂的基础理论和实际应用方面都有十分重要的研究价值。本文主要研究了阴离子表面活性剂油酸钠（NaOA）／无机电解质磷酸钠（Na₃PO₄）形成的蠕虫状胶束体系的流变性质，包括表面活性剂浓度、电解质浓度、温度、低分子量醇、正构烷烃、无机盐、油田水质矿化度、聚合物等因素对体系流变性质的影响。从理论上丰富了表面活性剂流变性质的研究，为拓宽阴离子表面活性剂在工业中的应用，特别是在石油开采领域的应用，提供了重要的理论基础。从考察阴离子表面活性剂NaOA在无机电解质Na₃PO₄存在时的剪切粘度变化入手，通过冷冻蚀刻透射电镜和流变实验，证实了NaOA／Na₃PO₄体系在合适的表面活性剂和电解质浓度时可以形成蠕虫状胶束。NaOA／Na₃PO₄蠕虫状胶束体系为假塑性流体，没有屈服应力现象，基本符合Cox-Merz规则。较低的剪切速率时，体系剪切粘度变化不明显；剪切速率较高时，胶束网络结构被破坏而使剪切粘度下降。蠕虫状胶束体系的储能模量和损耗模量曲线在一定振荡频率时相交。低频时损耗模量较大，粘性较强；而高频时储能模量较大，弹性较强。体系的动态粘弹性基本符合Maxwell模型。进一步考察其它因素对体系流变性质的影响发现：随温度升高，体系剪切粘度下降，粘度越大的体系剪切流动活化能越小。低分子量的醇和正辛烷的加入都会使表面活性剂的堆积因子R_p减小，胶束由蠕虫状向球状转变，剪切粘度下降。结合在三次采油中的实际应用，考察钠盐，镁盐浓度以及油田水质矿化度对蠕虫状胶束体系的影响。结果表明，随溶液矿化度的增大，体系剪切粘度有所下降，但并不显著，说明较高的矿化度对NaOA／Na₃PO₄体系的胶束结构和流变性质影响不大。部分水解聚丙稀酰胺（HPAM）由于本身带负电荷与油酸根离子具有较强的排斥作用，所以HPAM的加入会一定程度上抑制胶束的生长及网络结构的形成，使剪切粘度降低。HPAM浓度较大时，剪切粘度又会明显上升。论文第三章针对胜利油田孤岛原油，对三次采油驱油剂的筛选和应用作了较系统全面的研究。通过油水界面张力测定实验和室内模拟驱油实验发现，美国Dow化学公司的系列驱油剂均不能使孤岛油田原油的油水界面张力达到超低，并不适合在孤岛油田的采油应用。改性天然羧酸盐表面活性剂HF-2以及双子羧酸盐表面活性剂C18与复碱形成的驱油体系，不仅能使油水界面张力降至超低，同时具有很好的驱油效果，能较有效地驱出一次水驱后的残余油。以蠕虫状胶束流变性质的研究为理论基础，我们把蠕虫状胶束体系应用于三次采油。此驱油体系中不含有聚合物，既能提高洗油效率，又能提高波及系数。室内模拟驱油实验结果表明，该体系驱油效率基本均超过20％，说明蠕虫状胶束体系用作驱油剂，在三次采油中的确具有很好的应用前景。更多还原

【Abstract】 In the first two chapters, the rheological properties of wormlike micelles formed by the anionic surfactant were examined in detail.The rheological properties of surfactant aggregates are functions of both the structural arrangement of particles and the various interaction forces which operate in the system. It is very worthy to be considered for the theory and application of surfactants. In this dissertation, the rheological properties of wormlike micelles formed by anionic surfactant sodium oleate（NaOA）/sodium phosphate（Na₃PO₄） were investigated, including the effects of the concentration of surfactants and electrolytes, temperature, alcohols with small molecular weight, octane, inorganic salts, the mineralization of oil field water and polymer on the rheological properties. Some interesting and noticeable results will enrich the rheological studies of surfactant aggregates, and their applications in industrial fields, especially in enhanced oil recovery（EOR）.It is found that the wormlike micelles will be formed in anionic surfactant NaOA/Na₃PO₄ solutions with a proper surfactant and salt concentrations by shear viscosity measurements and freeze-fracture TEM micrographs. The characteristics of a pseudo-plastic fluid and zero yield stress were acquired from the steady-shear experiments. In a lower shear rate range, the viscosity of the samples have no obvious change; if the shear rate is high, the network structures of the wormlike micelles can be broken down, which results in a decrease in viscosity. The curves describing storage and loss moduli intersect for the wormlike micelles as the frequency increasing, indicating that the materials are more viscous than elastic at low frequencies and more elastic than viscous at high frequencies. The wormlike micellar solutions are linear viscoelastic fluids in accord with Maxwell model and Cox-Merz rule.The effects of other factors on the rheological properties were investigated generally. Shear viscosity decreases under the condition of increasing temperature, a higher viscosity systems have a smaller shear activation energy. The addition of acohols with small molecular weight or octane can reduce the R_p value and viscosity of the NaOA/Na₃PO₄ system. The mineralization of oil field wate has few effects on the rheological properties of wormlike micelles. HPAM has some interactions with the micellar molecules and is able to restrain the formation of network structures of wormlike micelles.In the third chapter, the oil displacement agents for Shengli Oil Field were studied systematically by the oil-water interfacial tension measurements and core flood test in laboratory. The serial oil displacement agents from Dow Chemistry Company can not be applied in Shengli Oil Field. The reshaped surfactants of natural carboxylic salt（HF-2）, the gemini surfactants of natural carboxylic salt（C18） and the wormlike micelles systems are considered to be good oil displacement agents for their abilities of enhancing sweep efficiency and absorption oil effect.更多还原