微乳助排剂的研制及性能评价

Preparation and performance evaluation of the microemulsion cleanup additive

采用两性表面活性剂、双子表面活性剂和非离子表面活性剂作为主剂、添加助剂及油相,复配得到了具有低表面张力和低界面张力的微乳液,并对其粒径、热稳定性、改善水润湿性能力、与压裂液配伍性及返排提高率进行评价,得到了具有优异助排效果的微乳液体系。结果表明:该体系粒径分布约80nm,其表面张力平衡值约26.0mN/m,与煤油间界面张力最低可降至<0.1mN/m,可改善云母表面润湿性,与其接触角最高改善约70°,返排提高率最高达到了29.72%;微乳液具有一定的耐温性,且与压裂液、添加剂和破胶液配伍性良好。

Using amphoteric surfactant, gemini surfactant and non-ionic surfactant as the main agents, compounding different types of surfactants, additives and oil phases, microemulsion with low surface tension and interfacial tension has been synthesized . And the particle size,thermal stability, capacity of improving wettability, compatibility with fracturing fluid and the flowback rate wereevaluated, finally the microemulsion system with excellent cleanup effect was obtained. Tndicate that the range of particle size is about 80 nm, its equilibrium value of surface te26. 0 mN/m, the interfacial tension between microemulsion and kerosene is below 0. 1 mN/m, which could improve the wettability of mica surface and the contact angle is improved by about 7.0 °,so the lowback rate can be up to 29. 72%. The microemulsion has thermal resistance, and the compatibility with the fracturing iluid, additives and gel breaking liquid is good.