Interfacial tension measurement on light oil from Fang oilfield with alkaline solution

Abstract

Alkaline flooding is one of the chemical process which help to improve the oil recovery by reducing the interfacial tension between oil and aqueous alkaline solution. In this research, the interfacial tension measurement of oil from Fang oilfield would be studied with various parameters such as pressure, temperature, alkaline types, alkaline concentration, salinity concentration and divalent ion. From the results, the effects of each parameter are different on the interfacial tension. When the pressure changes, the interfacial tension tend to be constant due to the experimental system are liquid phase. The effects of alkaline types on the interfacial tension are presented that the strong base alkaline solution can reduce the interfacial tension greater than the weak base alkaline solution at the same concentration because the dissociation of the strong base can completely occur compared to weak base. Therefore, the strong base alkaline can from the in-situ surfactant higher than the weak base alkaline. The strong base alkaline can reduce the interfacial tension down to 0.2 dynes/cm while the weak base alkaline can reduce the interfacial tension down to 0.6 dynes/cm. Temperature is also one of the parameters that affect the interfacial tension in the opposite direction. The increment of temperature would reduce the interfacial tension. Alkaline concentration and salinity affect the interfacial tension in the same direction. The increment of these two parameters would reduce the interfacial tension. The divalent ion has small effect on the interfacial tension.