阴阳离子双子表面活性剂在清洁压裂液中的应用

Application of anionic-cationic Gemini surfactants in clean fracturing fluid

采用阳离子双子表面活性剂GC-18与阴离子双子表面活性剂GA-12复配,并引入有机阴离子,得到新型清洁压裂液VES-GCA。通过测定不同质量浓度的GA-12与有机阴离子添加剂X对压裂液体系黏度的影响,得到压裂液最优配方为0.10 g/L GC-18+0.10 g/L GA-12+0.03 g/L X。研究表明,该压裂液体系在70℃,170 s-1条件下,表观黏度在30 mPa.s以上,能够满足清洁压裂液的携砂要求;抗剪切能力良好,破胶能力强,破胶后无残渣,对地层伤害小,且具有添加量低的优点,在中低温、低渗储层的压裂改造中具有良好的应用前景。

New clean fracturing fluid VES-GCA is prepared by mixing the cationic Gemini surfactant GC-18 with anionic Gemini surfactant GA-12 and introducing the balancing organic anions into the mixed system.By measuring the influence of different dosage of GA-12 and organic anion additive X on the viscosity of fracturing fluid,the optimized formulation is obtained,which is 0.10 g/L GC-18 ＋ 0.10 g/L GA-12 ＋ 0.03 g/L X.The study shows that the apparent viscosity of fracturing fluid system at the shear rate of 170 s-1 and 70 ℃ stabilizes at over 30 mPa·s,which meets the viscosity demand of sand-carrying.This clean fracturing fluid has characteristics of good shear capacity,strong gel breaking ability,gel-free residue and less damage to the formation.For the property of low surfactant concentration,it has a broad application prospects in the fracturing operation of medium-low temperature and low permeability reservoir.