一种稠油热/化学驱用表面活性剂性能研究

Performance Study on One Surfactant for Heavy Oil Thermal/Chemical Flooding

关键词:  稠油  热/化学驱  表面活性剂  耐温性能  驱油试验

Key words:  heavy oil  thermal/chemical flooding  surfactant  temperature resistance  oil flooding tests

摘要:

对一种热采用表面活性剂LC进行了性能评价,LC与孤岛三区原油动态界面张力在10-1mN/m数量级,与NaOH复配时则可达到超低界面张力。70℃下,LC在石英砂上的静态吸附量为3.618 5 mg/g。LC在150℃下具有很好的耐温性能,200℃下半衰期也在15天以上。LC溶液与原油质量比3∶7和2∶8混合,降粘率都在85%以上。150℃下动态驱替试验表明,采收率随着加入表面活性剂浓度的增大而增大,但是,活性剂浓度不宜太高;LC与0.5%的NaOH复配能显著提高采收率,当LC商品浓度为0.5%时,热水/碱/表面活性剂驱采收率比热水/碱驱提高10.85%,说明碱与表面活性剂具有很好的协同效应。试验表明LC可以作为稠油热采添加剂。

Abstract:

The Performance of one surfactant for thermal recovery was evaluated by experiment. The interiacial tension (IFT) of crude oil from Gudao third block in LC solution is 10-1mN/m,ultra—low IFT can be further achieved when NaOH was added.Static adsorption result showed that the maximum adsorption of LC on quartz sand at 70°C is 3. 6185mg/g, Besides, LC has good temperature resistance at 150°C ; even at 200°C, its half—time is longer than 15 days. When LC solution and crude oil were mixed in mass ratio of 3/7 and 2/8 at 70°C, oil viscosity can be dramatically decreased by more than 85%. Heavy oil dynamic flooding tests at 150°C indicated that oil recovery raises with the increase of LC concentration, but the concentration of surfactant should not be too high in consideration of its cost. When 0. 5wt% NaOH was compounded with 0.5wt% LC, oil recovery of hot water/alkali/surfactant flooding is 10.85% higher than that of hot water/alkali flooding, exhibiting good synergistic effect between NaOH and LC. It can be concluded that LC is a promising thermal additive in thermalrecovery of heavy oil.