驱油用表面活性剂AF性能评价及驱油效果研究

评价了脂肪酸烷醇酰胺表面活性剂AF的界面张力和乳化性能,利用岩心驱替实验对其提高采收率效果进行了研究。结果表明,在模拟地层水的矿化度为5 119.63 mg/L时,AF浓度为0.2%～1.2%,其界面张力均能达到超低值;NaCl浓度为0.4%～2%,AF有效浓度为0.3%～0.6%时,体系的界面张力均能达到10-3mN/m数量级。AF具有较好的乳化原油的能力,在浓度为0.5%时,形成的O/W乳状液的稳定性最强,液滴粒径最小。岩心驱替实验表明,AF表面活性剂可在水驱基础上提高原油采收率20%以上,提高采收率效果明显,具有良好的应用前景。

Study on properties and displacement efficiency of AF surfactant flooding

Interfacial tension(IFT) and emulsification property of fatty acid alkanolamide surfactant(AF) were investigated,and oil displacing efficiency of AF was evaluated by core flooding experiments.The results showed that AF could maintain IFTs of 10-3 mN/m at the concentration of 0.2%～1.2% in formation water salinity of 5 119.63 mg/L.It was indicated that AF surfactant kept its ultralow IFT of magnitude 10-3 mN/m when NaCl 0.4%～2% and AF concentration of 0.3%～0.6%.AF surfactant had good ability of emulsifying crude oil,the stability of oil-in-water emulsion was the strongest and the droplet size was minimum at the AF concentration of 0.5%.Experiments of oil displacement by AF surfactant presented that AF could enhance oil recovery factor on the basis of water-flooding,and the average oil recovery increment was more than 20%.