Laboratory Investigation of Enhanced Heavy Oil Recovery by Foam Flooding with Low Gas–Liquid Ratio

Abstract

This article presents the results of a laboratory study of foam flooding with low gas–liquid ratio for heavy oil in Shengli oilfield. Foam flooding tests were performed in cores, sandpacks, and using a 3D physical model to study the factors affecting displacement efficiency such as gas–liquid ratio, injection slug size, and the viscosity of crude oil. The results showed that the tertiary oil recovery of polymer-enhanced foam flooding with a gas–liquid ratio of 0.2:1 could reach 39% for heavy oil with a viscosity of 325 mPa · s at 55°C, which was 11% higher than alkali/surfactant/polymer flooding by injecting 0.3 pore volume of the same chemical slug. However, the tertiary oil recovery decreased with increasing viscosity of the crude oil.

Keywords:

• ASP flooding
• enhanced oil recovery
• foam flooding
• heavy oil
• low gas–liquid ratio

Notes

*The viscosities are measured at 55°C and the speed is 6 r/min.