Observation of Water Flow around Trapped Oil Blobs

摘要

Injection of sweeping agent (surfactant, steam, etc) in tertiary recovery will only extract some additional oil; usually 70% of total oil. To produce it, sweeping agent has to make a contact with trapped oil. The existence of oil blobs may cause such a disturbance in injected flow field so that preventing contact between sweeping agent and trapped oil, but there is no strong evidence of it. Advanced micro-focused X-ray CT scanner technology enables us to directly observe water flow phenomena around trapped oil blobs. We injected water upward into packed glass beads, scanned it, and constructed 3-D images from it. Injection of additional miscible fluid representing sweeping agent in actual tertiary recovery process was able to invade pores located just next to trapped oil. There is very thin stagnant water comes from previous water flooding process preventing the contact between trapped oil and additional miscible fluid.