表面活性剂SⅡ与稠油油田C原油相互作用研究

Interaction Between Surfactant SⅡ and Crude Oil From Bohai C Heavy Oilfield

为了研究表面活性剂SⅡ在渤海C稠油油田的适应性,利用超低界面张力仪、界面流变仪、体式显微镜、驱替装置等仪器从微观和宏观两种尺度研究了表面活性剂SⅡ与渤海C油田原油的相互作用及提高采收率性能。微观研究结果表明:随着SⅡ质量浓度的增加,油水界面张力不断下降,界面扩张模量不断增大。当SⅡ从0增加为2000 mg·L-1时,油水界面张力从1.53 mN·m-1下降至0.047 mN·m-1。显微镜观察结果显示在模拟水-SⅡ-原油体系中形成了水包油乳状液,油滴以球状或类球状分散于SⅡ溶液中。宏观研究结果表明当SⅡ质量浓度为2000mg·L-1、稠油与表面活性剂体积比例为3∶7时,形成的乳状液黏度相对原油黏度降幅高达96.1%。在水驱达到含水98%的填砂模型上注入0.4 PV、2000 mg·L-1的SⅡ溶液后,提高采收率幅度高达10.33%。研究表明对于渤海C稠油油田,SⅡ乳化驱替是一种可行的提高采收率方法。

In order to study the adaptability of surfactant SⅡin Bohai C heavy oil field,the interaction between surfactant SⅡsolution and the crude oil from C oil field was studied by the measurement of the interfacial tension(IFT)and the interfacial dilational modulus(IDM),the observing of microscopic dispersion of the oil-SⅡ-water system(OSWS).The results indicated that the IFT decreased with the concentration increasing of SⅡ.The IFT decreased from 1.53 m N·m-1 to 0.047 m N·m-1 as the concentration of SⅡchanged from 0 to 2000 mg·L-1.The IDM increased with the concentration increasing of SⅡ;O/W emulsion was formed in the OSWS,the oil was dispersed as spherical or elliptical droplets in SⅡsolution.On the basis of microcosmic study,the viscosity reduction and EOR performance were studied by macroscopic experiment.The results showed that the viscosity reduction rate was up to 96.1%when crude oil-SⅡsolution volume proportion was 3∶7 under the SⅡconcentration of 2000 mg·L-1.EOR by emulsion flooding reached 13.0%at the slug size of 0.4 PV under the SⅡconcentration of 2000 mg·L-1.The results of these studies shows that SⅡemulsion is a promising EOR technology in waterflooded heavy oil reservoirs.