稠油乳化降黏体系提高采收率

Enhanced Oil Recovery by Heavy Oil Emulsified Viscosity System

为了解决胜利油田陈家庄稠油黏度大、开采难的问题,考察了阴离子烯烃类磺酸盐乳化降黏剂SS、阴离子烷烃类磺酸盐乳化降黏剂SD、非离子乳化降黏剂SF以及SS+SF(质量比1∶1)和SD+SF(质量比1∶1)复配体系降低油水界面张力的能力和乳化稠油的能力,并采用SS、SF、SS+SF溶液进行了微观可视化驱油实验。研究结果表明,在质量分数0.4%,温度25℃下,SD、SS阴离子乳化降黏剂体系与模拟油的界面张力分别为1.87×10-2mN/m和1.21×10-2mN/m,与稠油模拟油(黏度187 m Pa·s)形成乳状液(质量比3∶7)的黏度分别为42 mPa·s和46 mPa·s;在微观驱油过程中,阴离子乳化降黏剂SD、SS的提高采收率分别为56.75%、61.93%。同样条件下,SS+SF体系具有优于单组分乳化降黏剂的界面活性和提高采收率能力,界面张力降至1×10-4mN/m以下,与稠油模拟油形成的乳状液黏度为30 mPa·s,相对于SF乳化降黏剂提高采收率14.93%。SS+SF乳化降黏剂有望用作普通稠油油田的驱油处理剂。

Aiming at the problem of large viscosity and mining difficulty in Chenjiazhuang heavy oil production in Shengli oilfield,the ability of emulsified viscosity reducer to reduce the interfacial tension between oil and water and the ability to emulsify heavy oil were investigated,including emulsified viscosity reducer SS(anionic olefin sulfonates),SD(Anionic alkane sulfonates),nonionic emulsification viscosity reducer SF,SS + SF(mass ratio 1∶1)and SD + SF(mass ratio 1∶1)compound system. The microscopic experiments were conducted using SS,SD,SF and SS + SF systems. the experimental results showed that under the condition of mass concentration of 0.4% and temperature of 25℃,the interfacial tension between the simulated heavy oil and the emulsification viscosity reducer SD or SS system was 1.87×10^-2mN/m and 1.21×10^-2mN/m,respectively,the viscosity of the emulsion formed with heavy oil,whose viscosity was 187 m Pa·s,in mass ratio of 3∶7 was 42 mPa·s and 46 mPa·s,respectively. In the microscopic oil displacement process,the enhanced oil recovery rates of SD and SS anionic emulsification viscosity reducers system were56.75% and 61.93%,respectively. Under the same conditions,the interfacial activity and ability to enhance oil recovery of SS+SF system was superior to that of the single component,the interfacial tension was reduced to 1×10^-4m N/m or less,the viscosity of the emulsion with heavy oil was 30 mPa·s,and compared with the SF emulsifying viscosity reducing agent system,the recovery rate was enhanced by 14.9%. The emulsion viscosity reducing agent SS + SF was expected to be used as oil displacement agent in ordinary heavy oil field.