Low salinity waterflooding for a carbonate reservoir: Experimental evaluation and numerical interpretation

The main conclusions of the study are: 1- The spontaneous imbibition and qualitative USS experiments showed extra oil production when switching from formation brine to seawater or diluted seawater subsequently, 2- Oil recovery by LSF can be maximized by injection of brine at a certain salinity threshold, at which lowering the brines salinity further did not lead to additional recovery improvement, 3- The LSF effect and optimal brine salinity varied in different layers of the reservoir which indicates that within the same reservoir the LSF effect is quite dependent on the rock type/property and mineralogy, 4- The quantitative USS showed that LSF can improve the oil recovery factor by up to 7% at core scale compared to formation brine injection.