Critical review of low-salinity waterflooding

The low-salinity effect (LSE) in carbonate rock has been less explored in comparison to sandstone rock. Laboratory experiments have shown that brine composition and (somewhat reduced) salinity can have a positive impact on oil recovery in carbonates. However, the mechanism leading to improved oil recovery in carbonate rock is not well understood. Several studies showed that a positive low-salinity flooding (LSF) effect might be associated with dissolution of rock; however, because of equilibration, dissolution may not contribute at reservoir scale, which would make LSF for carbonate rock less attractive for field applications. This raises now the question whether calcite dissolution is the primary mechanism of the LSF effect. In this paper, we aim to first demonstrate the positive response of carbonate rock to low salinity and then to gain insight into the underlying mechanism(s) specific to carbonate rock. We followed a similar methodology as in sandstone rock [Mahani, H.; Berg, S.; Ilic, D.; Bartels, W....

Insights into the Mechanism of Wettability Alteration by Low-Salinity Flooding (LSF) in Carbonates

Review of the litterature available outside the petroleum industry concerning wettability. This litterature discusses surface forces and their effects on wettability, including van der Waal and electrostatic forces. Hydrogen bonding and ion/water interactions, are also discussed. Advancing and receding contact angles for oil/water/mineral systems in terms of these surface forces are described.

Wettability : fundamentals and surface forces

Electrokinetics of Carbonate/Brine Interface in Low-Salinity Waterflooding: Effect of Brine Salinity, Composition, Rock Type, and pH on ζ-Potential and a Surface-Complexation Model

Ramez A. Nasralla

Papers

Insights into the Mechanism of Wettability Alteration by Low-Salinity Flooding (LSF) in Carbonates

Electrokinetics of Carbonate/Brine Interface in Low-Salinity Waterflooding: Effect of Brine Salinity, Composition, Rock Type, and pH on ζ-Potential and a Surface-Complexation Model

Double-Layer Expansion: Is It A Primary Mechanism of Improved Oil Recovery by Low-Salinity Waterflooding?

Investigation of Wettability Alteration and Oil-Recovery Improvement by Low-Salinity Water in Sandstone Rock

Wettability Studies Using Low-Salinity Water in Sandstone Reservoirs