STABILITY AND RHEOLOGY OF HEAVY CRUDE OIL-IN-WATER EMULSION STABILIZED BY AN ANIONIC- NONIONIC SURFACTANT MIXTURE

The stability and rheology of an Egyptian Heavy crude oil-in-water emulsions stabilized by an anionic (TDS) and a nonionic (NPE) surfactants individually or in a mixture have been studied. The study reveals that, the viscosity of the crude oil decreases when it is emulsified with water in the form of an oil-in-water type of emulsion. The stability of the oil-in-water emulsion increases as the surfactant concentration and speed of mixing of the emulsion increases. Fresh water and synthetic formation water have been used to study the effect of aqueous phase salinity on the stability and viscosity of the emulsion. Surfactant dissolved in synthetic formation water has been utilized to find out the possibility of injecting the surfactant into a well bore to effect emulsification in the pump or tubing for enhancing the production of heavy crude oils as oil-in-water emulsion. The study revealed that, the viscosity of the emulsion containing fresh water is always less than that containing formation water, these findings have been correlated with the crude oil/water interracial tension (IFT) measurements The decreased IFT value results in a decrease in the average particle size of the dispersed crude oil leading