二氧化碳驱后剩余油重组分胶束增溶技术

Recovery of Heavy Oil Remaining after CO₂-EOR by Micellar Solubilization

杨立安 李建山 吕 伟 屈 肖 李沫儀 方译苇 赵学之 冯玉军

YANG Li’an LI Jianshan LYU Wei QU Xiao LI Moyi FANG Yiwei ZHAO Xuezhi FENG Yujun

CO2驱油过程中，超临界CO2会萃取原油中的轻质组分，使得重质组分残留，不仅导致采收率难以大幅度提升，沉积的重组分还会堵塞孔喉，给储层带来不可逆损害。针对这一问题，本工作提出表面活性剂胶束增溶CO2驱后剩余油重组分的新思路，优选表面活性剂十二烷基苯磺酸钠（SDBS）和脂肪醇聚氧丙烯醚硫酸盐（APS）构建增溶胶束体系，利用吸光度法量化表面活性剂胶束对CO2驱后重质油的增溶能力，利用冷冻透射电镜、动态光散射等技术考察了增溶过程中胶束尺寸和形貌的变化。结果表明，表面活性剂胶束可有效增溶CO2驱后重质组分，0.2%的表面活性剂溶液对重质烷烃和重质芳烃的最大增溶量分别为 2.5、3.2 g/L。重质烷烃增溶于胶束内核，重质芳烃增溶于栅栏层。

During CO2-EOR，supercritical CO2 will extract the light components in the crude oil，resulting in the heavy components residue，which not only makes it difficult to greatly enhance the oil recovery，but also causes blockage of the pore throat and irreversible damage to the reservoir. To solve this problem，a new idea of surfactant micelle solubilizing heavy components after CO2 flooding was proposed in this work. Sodium dodecylbenzene sulfonate and aliphatic alcohol polyoxypropylene ether sulfate were selected to investigate their micellar solubilization behavior for heavy components. The changes of micelle size and morphology during solubilization were investigated by dynamic light scattering and transmission electron microscopy. The results showed that the surfactant micelles could solubilize effectively the heavy components after CO2 flooding. The maximum solubilization capacity of 0.2% surfactant solution to heavy alkanes and heavy aromatics was 2.5 g/L and 3.2 g/L，respectively. Heavy alkanes were more soluble in micelle core while heavy aromatics in palisade layer.

10.19346/j.cnki.1000-4092.2025.01.018