中文摘要：

为了高效清除井壁及套管壁上残留的油基钻井液、提高水泥环与环空界面胶结强度,根据表面活性剂盐水溶液与油接触后表面活性剂组装形成油水界面膜包裹油相而原位形成微乳液的原理,以琥珀酸二（2-乙基己酯）磺酸钠（AOT）、异构十三醇聚氧乙烯醚（AEO5-13）的复配体系为主表面活性剂,以柴油或白油为油相制备微乳液,通过考察微乳液增溶参数、界面张力等主要性能指标,确定了微乳液型冲洗液配方：KCl盐水（清洗柴油基钻井液时质量分数为7%,清洗白油基钻井液时质量分数为10%）＋4%AOT＋3%AEO5-13＋6%正丁醇,并评价了该冲洗液的润湿反转能力、冲洗效率及与钻井液和水泥浆的相容性。研究结果表明,随盐度增加,微乳液相态经历Winsor Ⅰ型到Winsor Ⅲ型再到Winsor Ⅱ型的转变,Winsor Ⅲ型微乳液具有最佳的增溶参数和界面活性,形成Winsor Ⅲ型柴油微乳液及白油微乳液的最佳盐度分别为7%和10%。微乳液型冲洗液的润湿反转能力强、冲洗性能优越,7 min对油基钻井液冲洗效率达95%以上,且与钻井液及水泥浆的相容性好。

英文摘要：

Removing oil-based mud adhered to borehole and casing walls efficiently is crucial to develop an excellent cement bond of the interface and cementing quality. When the surfactant and salty solution contacts with the oil, the surfactant can form interracial film and wraps the oil, resulting in that the microemulsion is formed in situ. According to that, the microemulsions were prepared with sodium 2-ethylhexyl sulfosuccinate （AOT） and iso-tridecanol polyoxyethylene ether （ AE05 - 13 ） as surfactants, diesel or white oil as oil phase. Solubilization parameter and interface tension of the microemulsions were investigated and a formula of microemulsion flushing fluid was prepared： KCl salty water ＋ 4% AOT＋ 3% AEO5-13 ＋ 6% n-butanol. The wettability alteration ability, flushing efficiency and the compatibility of microemulsion flushing fluid was evaluated. The experiment results showed that the microemulsion phase varied from Winsor Ⅰ to Winsor Ⅲ and then to Winsor Ⅱ with the increase of salt mass concentrations. The Winsor Ⅲ microemulsion possessed the optimum solubilization parameter and interracial activity, and the optimal salinity of Winsor Ⅲ dieesel microemulsion and white oil microemulsion was 7% and 10%, respectively. The density and theological property of microemulsion flushing fluid could be adjusted and its flushing ability was good. Performances evaluation showed that the wettability alteration ability of the flushing fluid was excellent, and the flushing efficiency for oil-based drilling fluid was higher than 95% in 7 min. The compatibility of microemulsion flushing fluid with oil-based drilling fluid and cementing slurry was excellent.