本研究利用文献中已有的纳米颗粒稳定的超临界CO2泡沫（NP CO2泡沫）实验，进行两项任务：（i）展示如何使用机理泡沫模型拟合实验数据并确定所需模型参数；（ii）通过CMG STARS模拟，对比纳米颗粒稳定的泡沫和表面活性剂泡沫在干法和湿法泡沫注入方法中的表现，研究在哥伦比亚Lisama油田类似条件下的驱油效率。结果表明，模型能成功复现实验数据，创建出三种不同的泡沫状态（弱泡沫、强泡沫和中间状态）以及两种稳态强泡沫状态（高质量和低质量状态）。当将模型拟合得到的气体流动性降低因子（高达10）应用于油田规模模拟时，使用纳米颗粒的方法比气水同注提高了石油采收率，但不如表面活性剂泡沫注入效率高。这意味着尽管纳米颗粒稳定的泡沫确实提供了一些好处，但仍有改进泡沫稳定性和强度的空间。
CMG软件应用情况
CMG STARS模拟软件用于矿场规模的模拟，以评估不同注入策略下的累积原油采收率、剩余油饱和度和扫油效率。模拟结果表明，纳米颗粒稳定的CO2泡沫虽然优于传统的气液同注（无泡沫），但驱油效率低于表面活性剂CO2泡沫。
ABSTRACT
Previous experimental studies show that nanoparticle-stabilized supercritical CO2 foams (or, NP CO2 foams) can be applied as an alternative to surfactant foams, in order to reduce CO2 mobility in gas injection enhanced oil recovery (EOR). These nanoparticles, if chosen correctly, can be an effective foam stabilizer attached at the fluid interface in a wide range of physicochemical conditions.
By using NP CO2 foam experiments available in the literature, this study performs two tasks: (i) presenting how a mechanistic foam model can be used to fit experimental data and determine required model parameters, and (ii) investigating the sweep efficiency in a condition similar to Lisama Field, in Colombia, by using relevant gas mobility reduction data in CMG STARS simulations, contrasting NP CO2 foams to surfactant foams in both dry and wet foam injection methods.
The results show how the model can successfully reproduce coreflood experimental data, creating three different foam states (weak-foam, strong-foam and intermediate states) and two steady-state strong-foam regimes (high-quality and low-quality regimes). When the gas mobility reduction factors ranging up to 10 from the model fit are applied in the field-scale simulations, the use of nanoparticles improves oil recovery compared to gas-water co-injection, but not as efficient as successful surfactant foam injection does. This implies that although nanoparticle-stabilized foams do provide some benefits, there still seems some room to improve stability and strength of resulting foams.
作者单位
Doris Patricia Ortiz Maestre 路易斯安那州立大学（Louisiana State University）石油工程系
