泡沫复合驱微观驱油特性分析

利用微观仿真光刻玻璃模型进行了驱油实验 ,对于亲水及亲油性不同的介质 ,利用图像采集系统将驱替过程的图像转化为计算机的数值信号 ,然后采用图像分析技术对碱表面活性剂聚合物泡沫复合驱的微观驱油特性进行了分析。特别对泡沫的挤压与占据作用、乳化油滴渗流、泡沫的选择性堵塞作用的分析结果表明 ,多元泡沫复合驱油过程中形成 3个条带 :前沿条带是混气复合体系及乳状液渗流 ;中间条带既有前沿条带中的两种渗流 ,也有泡沫渗流 ;后沿条带无油 ,以泡沫渗流为主。泡沫对驱扫盲端残余油有很大的优势 ,大泡将小泡挤入盲端 ,小泡将盲端中的油挤出。泡沫也具有明显的选择性堵塞作用 ,被驱出的油相及乳化的油滴可沿着泡沫之间的液膜绕过泡沫向前运移 ,这对于开发非均质性油藏极为有利。

Micro-visual analysis on oil displacement in alkaline-surfactant-polymer foam flooding

The hydrophilic and hydrophobic media with different pores were experimented with a micro imitated glass model to analyze the oil displacement process of alkaline-surfactant-polymer (ASP) foam flooding using the image analysis technology. The images of oil displacement process were collected and translated into numerical signals on computer by the image collecting system. The pressing, occupying and selective plugging actions of foam on pores of media as well as the percolation of emulsified oil drops were analyzed. The results show that the process of ASP foam flooding includes three areas, namely the front percolation area of ASP with gas and emulsified liquid; the middle area of ASP with gas, emulsified liquid and foam of ASP; the latter area of foam of ASP. The ASP foam plays an important role in displacing the residual oil in dead-end pores. The bigger bubbles press the smaller ones into dead-end pores, and the residue oil is displaced out. Meanwhile, the emulsified oil bypasses the foam in pores and flows along with the film of foam. The distinctly selective plugging action of foam is very advantageous to the development of heterogeneous reservoir.