CAJ | 학술논문

针对钻井液滤液侵入页岩储层极易导致严重的水敏损害及液相圈闭损害问题，采用两步稀释法研备出粒径极小、分散性好且长期稳定的页岩储层保护用水包油（O/W）纳米乳液。选取Gemini季铵盐型表面活性剂GTN、Tween80与正丁醇三者复配作为表面活性剂组分（记为S+A），通过室内实验研究了水相中NaCl质量分数对NaCl溶液/（S+A）/正辛烷体系微乳液特性的影响，考察了微乳液相转变温度（PIT）、制备方法及其微观构型等因素对采用两步稀释法制备的纳米乳液粒径的影响，同时对纳米乳液体系的失稳机理进行研究。结果表明，NaCl 溶液/（S+A）/正辛烷体系微乳液中 NaCl 的加入可以显著提高表面活性剂组分的乳化效率，改变微乳液微观构型，使PIT显著降低；当剂油体积比（Ros）为7：3时，通过调节双连续微乳液的PIT接近实验乳化温度，采用两步稀释法制备的O/W纳米乳液粒径最小且分布范围最窄；NaCl溶液/（S+A）/正辛烷体系纳米乳液主要失稳机理为奥氏熟化；纳米乳液具有良好的储层保护作用。
침대찬정액려액침입혈암저층겁역도치엄중적수민손해급액상권폐손해문제，채용량보희석법연비출립경겁소、분산성호차장기은정적혈암저층보호용수포유（O/W）납미유액。선취Gemini계안염형표면활성제GTN、Tween80여정정순삼자복배작위표면활성제조분（기위S+A），통과실내실험연구료수상중NaCl질량분수대NaCl용액/（S+A）/정신완체계미유액특성적영향，고찰료미유액상전변온도（PIT）、제비방법급기미관구형등인소대채용량보희석법제비적납미유액립경적영향，동시대납미유액체계적실은궤리진행연구。결과표명，NaCl 용액/（S+A）/정신완체계미유액중 NaCl 적가입가이현저제고표면활성제조분적유화효솔，개변미유액미관구형，사PIT현저강저；당제유체적비（Ros）위7：3시，통과조절쌍련속미유액적PIT접근실험유화온도，채용량보희석법제비적O/W납미유액립경최소차분포범위최착；NaCl용액/（S+A）/정신완체계납미유액주요실은궤리위오씨숙화；납미유액구유량호적저층보호작용。
There is a very prominent problem of water sensitive damage and liquid trap damage caused by drilling fluid during the exploitation process of shale gas reservoirs. A two-step dilution method for preparation of oil-in-water nanoemulsions used for the protection of shale gas reservoirs was introduced. The nanoemulsion could have small droplet sizes and fine dispersity. Selecting mixtures composed of Gemini hyamine surfactant GTN, Tween80 andn-butyl alcohol as surfactant component (referred to as S+A), the effects of mass concentration of NaCl on the properties of NaCl solution/(S+A)/n-octane systems was studied. The influence of the phase inversion temperature, emulsification methods and the structure of microemulsion on the droplet size of nanoemulsion was investigated. The instability mechanism of nanoemulsion system was researched. The results showed that increasing the concentration of NaCl could effectively change the microemulsion structure of NaCl solution/(S+A)/n-octane system, decrease the phase inversion temperature significantly and improve the emulsification efficiency. Oil-in-water nanoemulsions prepared by two-step dilution method had the smallest droplet size and the best dispersity atRos=7:3 when the emulsification temperature approached the phase inversion temperature. The mechanism of instability can be attributed to Ostwald ripening in NaCl solution/(S+A)/n-octane system. Nanoemulsion had good performance for protecting shale gas reservoirs.