Waterflood Oil Recovery from Mixed-Wet Limestone: Dependence upon the Contact Angle

Imaging of oil layers, curvature and contact angle in a mixed- wet and a water-wet carbonate rock

We have investigated the effect of wettability of carbonate rocks on the morphologies of remaining oil after sequential oil and brine injection in a capillary-dominated flow regime at elevated pressure. The wettability of Ketton limestone was altered in situ using an oil phase doped with fatty acid which produced mixed-wet conditions (the contact angle where oil contacted the solid surface, mea...

Pore-scale modeling: Effects of wettability on waterflood oil recovery

Oil Recovery by Spontaneous Imbibition from Weakly Water-Wet Rocks

Spontaneous imbibition is of special importance to oil recovery from fractured reservoirs. Laboratory measurements of volume of liquid imbibed versus time are often used in the prediction of oil recovery. Imbibition measurements also provide a useful approach to the complex problem of characterizing the wetting properties of porous media. Correlation of a large body of data for imbibition of br...

Surface Chemistry of Oil Recovery From Fractured, Oil-Wet, Carbonate Formations

Oil recovery by waterflooding in fractured formations is often dependent on spontaneous imbibition. However, spontaneous imbibition is often insignificant in oil-wet, carbonate rocks. Sodium carbonate and anionic surfactant solutions are evaluated for enhancing oil recovery by spontaneous imbibition from oil-wet carbonate rocks. Crude-oil samples must be free of surface-active contaminants to b...

Recovery of Oil in Limestone with Cationic Surfactant: Investigation of the Adsorption, Wettability, and Spontaneous Imbibition

The performance of petroleum recovery methods is dependent on the characteristics of the reservoir rock, oil quality, and formation water. One fundamental feature for considering petroleum recovery methods is the wettability of the rock reservoir. Also, this feature impacts the displacement of fluids in the rock reservior. In the case of the limestone, which normally features oil wettability, e...