An Experimental Study of Smart Water and Cedar Leaf Flooding as a Natural Surfactant for Enhanced Oil Recovery from Carbonate Reservoirs

Fractured carbonate reservoirs have low oil recovery efficiency due to wettability and tightness of rock matrix. One of the most applicable methods for enhanced oil recovery of carbonate reservoirs is to use smart water flooding. In addition using surfactants which have been obtained from Cedar leaf extract as a rich and cheap source leads enhanced oil recovery by improving the wettability properties. In this research, the effect of Ca2, Mg2 and SO42- concentrations in the smart water and also Cedar leaves extract concentration as a biosurfactant on wettability of carbonate rocks have been investigated. The analysis which is including contact angle measurments and cre flooding eperiments have been examined. Results showed the effect of Mg2 and Ca2 concentrations from 0.01 mol/L to 1 mol/L, SO42- concentration from 0.007 mol/L to 1 mol/L and biosurfactant concentration from 0.05 %(w/v) to 0.3 %(w/v) changes the carbonate wettability to water-wet, and oil recovery has increased from 35% to 57%. The contact angle has changed from 161 degrees to 41 degrees investigated in the 0.3 % (w/v) of biosurfactant concentration, which reflects the effect of the solution on the wettability of carbonate rocks.