低渗透油藏复配表面活性剂微乳液驱配方优选

Formula optimization of mixture surfactant system of microemulsion flooding in low permeability reservoir

阴-非离子型Gemini表面活性剂耐温、耐盐性能优越,且有较强的抗钙镁离子能力,不发生色谱分离,所以该类表面活性剂在三次采油中具有巨大的应用潜力。本文研究了阴-非离子型Gemini表面活性剂与烷基苯磺酸盐复配体系界面性能和乳化性能,并进行了微乳含量测定,确定最佳复配比为4∶1,在此基础上根据形成微乳含量确定最佳助剂为正丁醇,进而根据界面张力优选出最佳微乳液配方:0.4%ANG7-Ⅳ-7与烷基苯磺酸盐4∶1复配体系溶液/2%正丁醇溶液/原油。最后我们在低渗透油田岩心中进行不同类型微乳液驱油效果分析实验,该体系采收率达到47.3%,提高幅度最大,效果最好。

The anionic - nonionic Gemini surfactant has good temperature resistance, salt resistance and calcium and magnesium ion resistance. And it almost never occur chromatographic separation, so the surfactant has great potential applications in the tertiary oil recovery. In this paper, the interracial properties and emulsifying properties of anionic-nonionic Gemini surfactants and alkylbenzene sulfonate complex systems were studied. The optimum microemulsion concentration was determined to be 4：1. The optimal additive was n-butanol according to the microemulsion content, and the best microemulsion formula was selected according to the interracial tension： 0.4% ANG7-Ⅳ-7 mixed with alkyl benzene sulfonate 4：1 solution / 2% n-butanol solution / crude oil. Finally, the oil recovery efficiency of different types of mieroemulsions was tested in the core of low permeable oilfield. The recovery rate of the system was 47.3%, come to the biggest increase and the best effect.