Geochemical Interpretation of Low-Salinity-Water Injection in Carbonate Oil Reservoirs

The advantages of using the low-salinity-water-injection (LSWI) technique to improve oil recovery in carbonates are reported in the literature; however, the mechanism behind it is still uncertain. This paper represents a comparison between two geochemical simulators [ UTCHEM (UTCHEM manual, 2000) and PHREEQC (Parkhurst and Appelo 2013)] through modeling fluidand solid-species concentrations of a recently published LSWI coreflood. Moreover, an attempt to interpret the mechanism controlling the LSWI effect on oil recovery from carbonates is presented on the basis of the findings of this work. The LSWI technique is case-dependent, and hence, the findings cannot be generalized.