Injectivity of Multiple Gas and Liquid Slugs in SAG Foam EOR: A CT Scan Study

Surfactant-alternating-gas (SAG) is often the injection method for foam enhanced oil recovery (EOR) in order to improve injectivity. However, liquid injectivity can be very poor once foam is created in the near-wellbore region. In a previous study, we reported core-flood experiments on liquid injectivity after foam flooding and liquid...

Impact of Crude Oil on Pre-generated Foam in Porous Media

As foam is injected into an oil reservoir, the region near an injector can become oil-free due to the relatively high capillary number. Foam created in this region encounters oil further out in the reservoir. The impact of oil on foam in porous media is usually investigated by co-injecting surfactant, gas and oil, or by injecting pre-generated...

Foam Propagation at Low Superficial Velocity: Implications for Long-Distance Foam Propagation

Since the 1980s experimental and field studies have found anomalously slow propagation of foam that cannot be explained by surfactant adsorption. Friedmann et al. (1994) conducted foam-propagation experiments in a coneshaped sandpack and concluded that foam, once formed in the narrow inlet, was unable to propagate at all at lower superficial...

Fall-off test analysis and transient pressure behavior in foam flooding

Gas injection projects often suffer from poor volumetric sweep because under reservoir conditions the density and viscosity differences between the gas and the in-situ oil leads to override and bypassing of much of the oil in place. Foam has been suggested as a potential solution to this shortcoming and has shown success in some of the field...

Nanoparticle Stabilized Foam in Carbonate and Sandstone Reservoirs

Foam flooding as a mechanism to enhance oil recovery has been intensively studied and is the subject of multiple research groups. However, limited stability of surfactant-generated foam in presence of oil and low chemical stability of surfactants in the high temperature and high salinity of an oil reservoir are among the reasons for foam EOR not...

Small core flood experiments for foam EOR: Screening surfactant applications

Aqueous foams are a means of increasing the sweep efficiency of enhanced oil recovery processes. An understanding of how a foam behaves in the presence of oil is therefore of great importance when selecting suitable surfactants for EOR processes. The consensus is currently that the most reliable method for determining the foam behavior in the...