Effect of Temperature And Aging Time Factor On Wettability Alteration During Surfactant Flooding Process

About half of world’s known oil reserves are in carbonate reservoirs (Roehl 1985). However, many carbonate reservoirs (about 80%) are mixed-wet or oil-wet (Downs, 1989). Hence the efficiency of water flooding is very low as the rock surface is oil wet. In such cases using surfactant flooding has been suggested many times as an advantageous replacement for secondary recovery (Seethepalli et al 2004, Lu et al 2014). Surfactant flooding is an efficient approach for oil recovery from the carbonate reservoirs by a recovery of up to 70% Oil in Place or OOIP (Austad et al 1997, Standnes, et al 2003, Lu et al 2014). As the rock surface prefers oil, spontaneous imbibition does not occur in the reservoir, so break through time decreases and water cut approaches sooner, increasing water production while decreasing the beneficial oil production. In this study Dodecyl Trimethyl Ammonium Bromide or in abbreviation form DTAB is used as the surfactant element for wettability alteration from hydrophobic to hydrophilic in the limestone cores, to find the impact of temperature and aging time. It is observed that DTAB surfactant’s optimum workability is at T=80°C and for surfactant concentration 1.5 W%. The results show that in lower temperatures also the best result is gained for a higher concentration