Properties of Carbon Dioxide Foam Stabilized by Hydrophilic Nanoparticles and Hexadecyltrimethylammonium Bromide

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• 作者：Songyan LiChenyu Qiao ; Zhaomin Li ; Silagi Wanambwa
• 刊名：Energy & Fuels
• 出版年：2017
• 出版时间：February 16, 2017
• 年：2017
• 卷：31
• 期：2
• 页码：1478-1488
• 全文大小：740K
• ISSN：1520-5029

文摘

Nanoparticles can improve the stability of CO₂ foam and increase oil recovery during CO₂ flooding in reservoirs. The synergistic effect of hydrophilic SiO₂ nanoparticles and hexadecyltrimethylammonium bromide (CTAB) on CO₂ foam stability was examined in this study. Experimental results show that the synergistic effect requires a CTAB/SiO₂ concentration ratio of 0.02–0.07, with 0.033 representing the best concentration ratio. With the increase in the concentration ratio, the synergistic stabilization effect of CTAB/SiO₂ dispersion first increases and then decreases. In the monolayer adsorption stage (concentration ratio from 0.02 to 0.033), when the hydrophobicity of SiO₂ nanoparticles increases with the concentration ratio, the nanoparticles tend to adsorb on the gas–liquid interface and the stability of CO₂ foam increases. In the double-layer adsorption stage (concentration from 0.033 to 0.07), when the hydrophobicity of SiO₂ nanoparticles decreases with an increase in the concentration ratio, the nanoparticles tend to exist in the bulk phase and the stability of CO₂ foam decreases. The CTAB/SiO₂ dispersion stabilizes CO₂ foam via three mechanisms: decreasing the coarsening of CO₂ bubbles, improving interfacial properties, and reducing liquid discharge. CTAB/SiO₂ foam can greatly improve oil recovery efficiency compared to water flooding. Experimental results provide theoretical support for improving CO₂ foam flooding under reservoir conditions.