Emulsification of Indian heavy crude oil in water for its efficient transportation through offshore pipelines

The emulsification of heavy crude oil is the most economical way to transport it through offshore pipelines. In this research article, distinct oil-in-water (o/w) emulsions were developed from an Indian heavy crude oil using 4-(1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol. Ultrasonic waves of 26 kHz frequency, produced from Hielscher UP200Ht ultrasonic homogenizer, were used to disperse crude oil in water phase. The physicochemical characteristics of heavy crude oil were determined using standard methods adopted by the petroleum industries. The functional groups of the crude oil were analyzed using FTIR. Rheological behavior of crude oil and o/w emulsions were studied using Physica rheometer MC-1 model. Interfacial tension between crude oil and aqueous phase in developed emulsions were studied using a Texas-500 spinning drop tensiometer (Data-Physics, Model No: SVT 15 N). Droplet size distribution and surface tension of emulsions were analyzed using Zetasizer Nano S90 particle size analyzer and Kruss Easy Dyne tensiometer respectively. It was experimentally observed that the viscosity of developed emulsion were lower than the viscosity of neat crude, and at 60% of oil content and 2 wt% of surfactant, viscosity reduction is around 83%. A tremendous decrease in pour point was also observed after emulsification, making most of the emulsions to flow even at 1 °C. Moreover, most of the prepared emulsions were found to be highly stable even after 56 days of storage in ambient conditions. Hence, the prepared emulsions may be transported through the offshore pipelines efficiently.