SURFACTANT SELECTION FOR ENHANCING EMULSION MOBILITY USING INTERFACIAL TENSION MEASUREMENT

Abstract

Emulsion mobility is the crucial characteristic of fluid to increase oil production. In this study, surfactants are considered as chemical agents used in Northern oilfield, Thailand. The important role of surfactant is to reduce the interfacial tension (IFT) of two fluids and to make emulsion flow easier in the reservoir. The aim of this work is to investigate and measure the IFT based on the conditions of subsurface at the oilfield in Thailand. These parameters such as temperature, pressure, salinity, types of surfactant as well as the concentration of surfactant are adjusted to investigate the effects on IFT reduction. The results show that the pressure ranging from 1,000 psi to 2,000 psi at constant temperature has less significant effect on IFT reduction. For the effect of types of surfactant solution, monoethanolamine (MEA) is the best type of surfactant samples which has higher performance to reduce interfacial tension at the same concentration. Because of its amine group, MEA has a strong base that can dissociate in the solution and create more in-situ surfactant to lower IFT. Surfactant concentration is the main parameters that impact on the IFT reduction. It can greatly decrease IFT up to 87.13% for surfactant concentration. Temperature varied from 70C to 90C can insignificantly reduce the IFT. In addition, the increase of salinity can reduce interfacial tension, but it is relatively stable at high salinity. Lastly, the effect of divalent ions has less impact on the interfacial tension. These investigated effects of each parameter will be useful to understand the mechanism of IFT reduction, and they will be used as fundamental data to apply for oil recovery with reservoir conditions.