An Experimental Study of Foam Trapping and Foam Mobility in a Model Fracture

By trapping gas, foam can improve the sweep efficiency in enhanced oil recovery. In this study, to understand gas trapping in fractures, we have conducted experiments in a model fracture with a hydraulic aperture of 80 μm. One wall of the fracture is rough, and the other wall is smooth. The fracture is made of two glass plates and the direct...

Gravity segregation with CO2 foam in heterogeneous reservoirs

Foam injection is one efficient way to mitigate gravity segregation during CO2 injection into porous media. The effect of gravity segregation on foam propagation in heterogeneous porous media is not yet fully resolved. To assess CO2 foam transport for enhanced oil recovery (EOR) and for CO2 storage processes in heterogeneous reservoirs, an...

Simulation of foam-assisted co2 storage in saline aquifers

Geological storage of CO2 is a crucial emerging technology to reduce anthropogenic greenhouse gas emissions. Due to the buoyant characteristic of injected gas and the complex geology of subsurface reservoirs, most injected CO2 either rapidly migrates to the top of the reservoir or fingers through high-permeability layers due to instability in...

An Experimental Study of the Effect of Gravity on Foam in Fractures

In this study, to investigate how gravity affects foam in fractures, we carry out seven sets of foam-scan experiments on three glass model fractures (model A, model B and model C) with a hydraulic aperture of 78, 98 and 128 microns respectively. We compare the behaviour of foam in the models placed horizontally and vertically. We find that...

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...

Coreflood Study of Non-Monotonic Fractional-Flow Behavior with Foam: Implications for Surfactant-Alternating-Gas Foam EOR

Foam is able to increase gas’s sweep efficiency in Enhanced-Oil-Recovery applications. A surfactant-alternating-gas, or SAG, process is usually preferred for placing foam in the reservoir. During a SAG process, foam is generated away from the wellbore, offering both good injectivity and good mobility control at the leading edge of the foam bank....

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...

Foam Generation by Snap-off in Flow Across a Sharp Permeability Transition

Foam reduces gas mobility and can help improve sweep efficiency in an enhanced oil recovery process. For the latter, long-distance foam propagation is crucial. In steady gas-liquid flow, foam is generated in homogeneous porous media by exceeding a critical pressure gradient, which normally only happens near the wellbore. Away from wells, these...

Discerning in situ performance of an eor agent in the midst of geological uncertainty

An enhanced-oil-recovery pilot test has multiple goals, among them to verify the properties of the EOR agent in situ. Given the complexity of EOR processes and the inherent uncertainty in the reservoir description, it is a challenge to discern the properties of the EOR agent in situ. We present a simple case study to illustrate this challenge: a...

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...

Effect of Permeability on Foam-model Parameters and the Limiting Capillary Pressure

Accurate modelling of foam rheology on the field scale requires detailed understanding of the correlation between the fundamental properties of foam and the scalable parameters of the porous medium. It has been experimentally observed that foam experiences an abrupt coalescence when the capillary pressure in the porous medium approaches a...

Interfacial Interactions of CO2-Water-Bentheimer Sandstone System - Dissolution and Contact Angle

CO2 storage in deep saline aquifers and depleted gas reservoirs is largely controlled by interfacial phenomena among fluid phases and rock pore spaces. Reduction of the interfacial tension may result in the mobilization of connate water (capillary trapping). In addition, dissolving CO2 in formation water is one of the most important mechanisms...

Effect of Pressure on Wetting Properties of Crude Oil, Sandstone Rock, Water, CO2 and (or) Flue Gas System

Carbon dioxide injection, either miscible or immiscible, has been known as an efficient strategy to enhance oil recovery as well as reduce CO2 emission. Wettability has a significant effect on the performance of enhanced oil recovery techniques because of its effect on fluid saturation distribution and flow behavior in porous media. For oil-wet...

Fitting foam simulation model parameters to data

Interfacial Tension and Contact Angle Determination in Water-sandstone Systems with Injection of Flue Gas and CO2

Carbon capture and storage (CCS) has the potential for reducing CO2 emissions to the atmosphere. This option includes storage strategies such as CO2 injection into deep saline aquifers, depleted oil and gas reservoirs, and unmineable coal seams. This process is largely controlled by the interactions between CO2, the reservoir fluid and reservoir...

Injectivity Errors in Simulation of Foam EOR

Injectivity is a key factor in the economics of foam EOR processes. Poor injectivity of lowmobility foam slows the production of oil and allows more time for gravity segregation of injected gas. The conventional Peaceman equation, when applied in a large grid block, makes two substantial errors in estimating injectivity: it ignores the rapidly...