Use of a Novel Surfactant to Prepare Oil-in-Water Emulsion of an Indian Heavy Crude Oil for Pipeline Transportation

Abstract

This article thoroughly evaluates the performance of a synthesized surfactant as an emulsifier for the preparation of an Indian heavy crude oil-in-water (o/w) emulsion to enhance its ability to flow through offshore pipelines. The physico-chemical characteristics, wax content, wax appearance temperature, FT-IR spectrum, and high-temperature gas chromatogram of the heavy crude oil were analyzed first. High-frequency (26 kHz) ultrasonic waves were utilized to disperse heavy crude oil in water. Further evaluation included studies of the pour point, rheology, stability, droplet size distribution, and zeta potential of the prepared emulsions. The pour point and viscosity of the crude oil decreased drastically after preparation of the emulsion with water. Most of the prepared emulsions had a pour point of less than 3 °C. In order to minimize the amount of surfactant required, the effects of aqueous-phase salinity and pH on the emulsion properties were also studied. Although an increase in water salinity showed no significant positive effect on emulsion properties, an increase in water pH helped in achieving better flow ability as well as stability of the emulsions. These results suggest that a synthesized surfactant may be used to prepare stable o/w emulsions and transport them through offshore pipelines efficiently.