关键词:

纳米微乳液, 驱油剂, 三元相图, 助表面活性剂, 表面活性剂

Abstract:

Microemulsion flooding is an effective technology to improve oil recovery. Microemulsions were prepared using dodecyl betaine，isopropanol and 90 ~ 120 petroleum ether. The impact of Km，the ratio of cosurfactant to surfactant，on microemulsion was studied using the pseudo-ternary phase diagram method. The results show that with the increase of Km，the area of microemulsion formed increased first and then decreased，and reached the maximum when Km = 2. The nano-microemulsion oil displacement agent was prepared using the microemulsion dilution method. The particle size distribution and interfacial tension were measured by laser scattering system and spinning drop interface tensiometer，respectively. The results show that the average particle size is 149.0 nm when the concentration is 0.25 %，and the minimum interfacial tension is 1.780 44 mN/m when the concentration is 0.3 %. The properties of the nano microemulsion oil displacement agent were evaluated in the laboratory. The results show that it had good dispersion stability at different temperatures. The maximum foam height is 140 mm when the concentration is 0.5%；the maximum emulsification efficiency is 55.0% when the concentration is 0.3%；the maximum oil displacement efficiency is 88.39% when the concentration is 0.2%；when the concentration is 0.3%，the total oil recovery factor is 86.78%.

Key words:

"> nano microemulsion, oil displacement agent, ternary phase diagram, cosurfactant, surfactant