长短碳链甜菜碱型起泡剂的协同增效作用研究

Synergistic effect of long and short carbon chain betaine type foaming agent

关键词:  高温高盐  表面活性剂  甜菜碱  泡沫性能  封堵性能

Key words:  high temperature and high salt  surfactant  betaine  foam performance  plugging performance

摘要:

目的 在高温高盐(90 ℃、25×10⁴ mg/L)条件下对短碳链甜菜碱LHSB和长碳链甜菜碱OHSB按不同比例复配得到的起泡剂进行优选并得到具有良好封堵性能的泡沫体系。方法 使用Waring搅拌法评价了不同起泡剂的泡沫性能,并利用流变仪对其协同增效作用进行探讨,通过岩心实验考查了不同泡沫体系在多孔介质中的封堵效果。结果 由0.2% (w)LHSB和0.2% (w) OHSB构建的复合起泡剂S11具有较好的泡沫性能,起泡体积为345 mL,消泡半衰期为132 min,较LHSB起泡剂提高了3倍；岩心实验显示,S11泡沫的阻力系数和残余阻力系数分别为91.6和14.9。结论 将OHSB作为稳泡剂加入LHSB中,可使复合起泡剂表现出黏弹性表面活性剂的特征,从而降低排液速度,提高液膜强度,在泡沫稳定性方面表现出协同作用。 

Abstract:

Objective The foaming agents were prepared by the combination of betaine LHSB with short carbon chain length and betaine OHSB with long carbon chain length in different proportions at high temperature and high salt (90 ℃, 25×10⁴ mg/L) conditions, which were optimized to obtain a foam system with good plugging performance. Methods The foam properties of different foaming agents were evaluated by Waring stirring method, and the synergistic mechanism of the foam was discussed by rheometer. The plugging effect of different foaming systems in porous media was investigated through core experiment. Results The composite foaming agent S11 made from 0.2% LHSB and 0.2% OHSB has good foam properties, the foaming volume is 345 mL, the half life of defoaming is 132 min, and the performance of this foaming agent is 3 times higher than that of LHSB foaming agent. The core test shows that the drag coefficient and residual drag coefficient of S11 foam are 91.6 and 14.9, respectively. Conclusion sWhen OHSB is added in LHSB as stabilizer, the composite foaming agent can exhibit the characteristics of viscoelastic surfactant, which can reduce the drainage speed, improve the liquid film strength, and show synergistic effect in foam stability.