Low IFT drainage and imbibition

Schechter, David S.; Zhou, Dengen; Orr, Franklin M.

doi:10.1016/0920-4105(94)90047-7

Cited by 295 publications

(231 citation statements)

References 10 publications

Supporting

Mentioning

213

Contrasting

Order By: Relevance

“…Marangoni forces that arise because of interfacial tension gradients may also contribute to the recovery mechanism. Increase in the ratio of gravity to capillary forces and the role of connate water saturation will also come into play [82].…”

Section: Imbibition Of Surfactant Solutionsmentioning

confidence: 99%

Wettability and Imbibition: Microscopic Distribution of Wetting and Its Consequences at the Core and Field Scales

Buckley¹,

Morrow²,

Palmer³

et al. 2003

View full text Add to dashboard Cite

The main objectives of this project are:(1) to quantify the microscopic distribution of altered wetting that occurs in oil reservoirs as crude oil components adsorb on rock surfaces, and (2) to apply quantitative descriptions of wetting at the microscopic level to interpretation of imbibition in mixed-wet porous media. AbstractThe questions of reservoir wettability have been approached in this project from three directions. First, we have studied the properties of crude oils that contribute to wetting alteration in a reservoir. A database of more than 150 different crude oil samples has been established to facilitate examination of the relationships between crude oil chemical and physical properties and their influence on reservoir wetting. In the course of this work an improved SARA analysis technique was developed and major advances were made in understanding asphaltene stability including development of a thermodynamic Asphaltene Solubility Model (ASM) and empirical methods for predicting the onset of instability. The CO-Wet database is a resource that will be used to guide wettability research in the future.The second approach is to study crude oil/brine/rock interactions on smooth surfaces. Contact angle measurements were made under controlled conditions on mica surfaces that had been exposed to many of the oils in the CO-Wet database. With this wealth of data, statistical tests can now be used to examine the relationships between crude oil properties and the tendencies of those oils to alter wetting. Traditionally, contact angles have been used as the primary wetting assessment tool on smooth surfaces. A new technique has been developed using an atomic forces microscope that adds a new dimension to our ability to characterize oil-treated surfaces.Ultimately we aim to understand wetting in porous media, the focus of the third approach taken in this project. Using oils from the CO-Wet database, experimental advances have been made in scaling the rate of imbibition, a sensitive measure of core wetting. Application of the scaling group to mixed-wet systems has been demonstrated for a range of core conditions. Investigations of imbibition in gas/liquid systems provided the motivation for theoretical advances as well.As a result of this project we have many new tools for studying wetting at microscopic and macroscopic scales and a library of well-characterized fluids for use in studies of crude oil/brine/rock interactions.iv Table of , where v p is precipitant molar volume. Fits to these linear trends are summarized in Table I relationship used is that for A-93+ α-MN (Fig. I-3.5) with a temperature adjustment of -0.0008 RI units/°C. Solution gas is estimated to be xiii composed of methane, ethane, and propane with mole fractions of 0.5, 0.4, and 0. Figure I-3.27. Measured and predicted onset conditions for flocculation from crude oils induced by precipitants from n-pentane to n-pentadecane. Asphaltene molar volume = 2500 ml/mol. Other model parameters are given in Figure II-2.8. Example of the "memo...

show abstract

Section: Imbibition Of Surfactant Solutionsmentioning

confidence: 99%

Wettability and Imbibition: Microscopic Distribution of Wetting and Its Consequences at the Core and Field Scales

Buckley¹,

Morrow²,

Palmer³

et al. 2003

View full text Add to dashboard Cite

show abstract

“…If the interfacial tension is very low, capillarity becomes less important compared to buoyancy 4 . However, for systems that are preferentially oil-wet, spontaneous imbibition of brine usually does not occur and capillarity is the mechanism that retains oil in the matrix, as illustrated in Fig.…”

Section: Spontaneous Imbibitionmentioning

confidence: 99%

“…Reduction of interfacial tension reduces the contribution of capillary imbibition. Buoyancy, as measured by the product of density difference and the acceleration of gravity then becomes the dominant parameter governing the displacement, even if oil is the wetting phase 4 .…”

Section: Introductionmentioning

confidence: 99%

Surfactant Based Enhanced Oil Recovery and Foam Mobility Control

Hirasaki¹,

Miller²,

Pope³

et al. 2004

View full text Add to dashboard Cite

“…The numerator of is a measure of the capillary entry pressure. Schechter et al 28 found that for < 1, gravity segregation dominates the flow and that for high values of >1, capillary forces are dominant. Hagoort 36 has analyzed the 1-D gravity driven oil drainage by a gas, and the expressions for dimensionless time and recovery are:…”

Section: Introductionmentioning

confidence: 99%

Dilute Surfactant Methods for Carbonate Formations

Mohanty¹

2006

View full text Add to dashboard Cite

There are many fractured carbonate reservoirs in US (and the world) with light oil.Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). The process of using dilute anionic surfactants in alkaline solutions has been investigated in this work for oil recovery from fractured oil-wet carbonate reservoirs both experimentally and numerically. This process is a surfactant-aided gravity drainage where surfactant diffuses into the matrix, lowers IFT and contact angle, which decrease capillary pressure and increase oil relative permeability enabling gravity to drain the oil up.Anionic surfactants have been identified which at dilute concentration of 0.05 wt% and optimal salinity can lower the interfacial tension and change the wettability of the calcite surface to intermediate/water-wet condition as well or better than the cationic surfactant DTAB with a West Texas crude oil. The force of adhesion in AFM of oil-wet regions changes after anionic surfactant treatment to values similar to those of water-wet regions. The AFM topography images showed that the oil-wetting material was removed from the surface by the anionic surfactant treatment. Adsorption studies indicate that the extent of adsorption for anionic surfactants on calcite minerals decreases with increase in pH and with decrease in salinity.Surfactant adsorption can be minimized in the presence of Na 2 CO 3 .Laboratory-scale surfactant brine imbibition experiments give high oil recovery (20-42% OOIP in 50 days; up to 60% in 200 days) for initially oil-wet cores through wettability alteration and IFT reduction. Small (<10%) initial gas saturation does not affect significantly the rate of oil recovery in the imbibition process, but larger gas saturation decreases the oil recovery rate. As 3 the core permeability decreases, the rate of oil recovery reduces, and this reduction can be scaled by the gravitational dimensionless time.Mechanistic simulation of core-scale surfactant brine imbibition matches the experimentally observed imbibition data. In-situ distributions observed through simulation indicate that surfactant diffusion (which depends on temperature and molecular weight) is the rate limiting step. Most of the oil is recovered through gravitational forces. Oil left behind at the end of this process is at its residual oil saturation. The capillary and Bond numbers are not large enough to affect the residual oil saturation.At the field-scale, 50% of the recoverable oil is produced in about 3 years if the fracture spacing is 1 m and 25% if 10 m, in the example simulated. Decreasing fracture spacing and height, increasing permeability, and increasing the extent of wettability alteration increase the rate of oil recovery from surfactant-aided gravity drainage. This dilute surfactant aided gravitydrainage process is relatively cheap. The chemical cost for a barrel of oil produced is expected to be less th...

show abstract

Low IFT drainage and imbibition

Cited by 295 publications

References 10 publications

Wettability and Imbibition: Microscopic Distribution of Wetting and Its Consequences at the Core and Field Scales

Wettability and Imbibition: Microscopic Distribution of Wetting and Its Consequences at the Core and Field Scales

Surfactant Based Enhanced Oil Recovery and Foam Mobility Control

Dilute Surfactant Methods for Carbonate Formations

Contact Info

Product

Resources

About