摘要
为了研究碱体系提高采收率机理,采用旋滴界面张力仪测定Na2CO3溶液与原油的界面张力.结果表明Na2CO3可以与原油中的石油酸在界面上反应生成表面活性剂,活性剂不断富集在油-水界面上,界面张力逐渐降低,在反应的后期,反应逐渐减弱,扩散作用导致界面张力迅速升高,同时温度较高时也会增强扩散作用导致界面张力升高.通过测定油膜的收缩速率和可视化驱替实验表明：碱与原油反应产生的表面活性物质会吸附在油-固界面上降低油-固界面张力,增强固体表面的亲油性.温度升高导致的扩散作用会降低活性物质在油-固界面上的吸附量,因此温度较低时,碱具有更强的改变润湿性的能力,有利于降低水相渗透率,提高波及系数.
The mechanism of enhanced oil recovery by the alkaline system was researched. The IFT （ interfacial tension force） between Na2CO3 solution and oil was measured by spinning drop interracial tension meter. The resuits showed that the surfactant was produced during the reaction between Na2CO3 and petroleum acid. The IFT between oil and water reduced with the continuous concentration of the surfactant. In the end of the reaction, the reaction became weak, and the IFT increased quickly due to the diffusion effect. The diffusion effect would be enhanced at higher temperature and caused the raise of the IFT. The oil film shrink velocity in Na2CO3 solution and the visual displacement experiment showed that the surface active substance produced by the reaction between the alkaline and oil would adsorb to oil-solid interface and decrease oil-solid solid IFT, and the surface of the solid would become more oil-wet. The adsorbance of the active material to oil-solid interface would be reduced at higher temperature due to the diffusion effect. So the alkaline would be more effective to change the wettability under lower temperature, and that could decrease the water permeability and increase the sweep efficiency.
出处
《大庆石油地质与开发》
CAS
CSCD
北大核心
2010年第5期146-150,共5页
Petroleum Geology & Oilfield Development in Daqing
基金
国家高技术研究发展专项 ＂稠油油藏混气表面活性剂驱＂（ 2006AA06Z227）和新世纪优秀人才支持计划及山东省自然科学基金＂稠油油藏蒸汽驱后提高采收率用表面活性剂研究＂（Y2006F50）项目资助.
关键词
碳酸钠
表面活性剂
润湿性
碱驱
Na2 CO3
surfaetant
wettability
alkaline waterflooding
