Ultrasonic based methods to characterize stability of water-in-crude oil emulsions

The potential of ultrasonic techniques to characterize water-in-oil emulsions is investigated for possible indus trial applications. The emulsions for testing were prepared in mineral and crude oil samples of different types to study effects of selected variables and these were characterized for their stability and variations in droplet size distribution. Emulsions droplet structure was observed with optical microscopy and stability was examined by separation of water phase with time and changes were tracked by an ultrasonic probe. The ultrasonic parameters recorded were changes in acoustic velocity, signal attenuation and frequency spectrum of the propagating wave. The applicability of the technique to characterize emulsions of crude oils with different asphaltene content has been clearly demonstrated based on extensive testing and data analysis. The technique has been applied for the first time to determine acceptable levels of asphaltene content in crude oil to avoid formation of very stable emulsions. Attenuation measurements provided better illustration of water separation process from different emulsions compared to measurements of volume of water separated. Observed attenuation effects in ultrasonic wave have been linked to emulsion system rheology.

Automated summary

The potential of ultrasonic techniques in characterizing water-in-oil emulsions was investigated for industrial applications by studying stability and droplet size distribution in different mineral and crude oil samples. The technique was successfully applied to characterize emulsions with varying asphaltene content in crude oils, demonstrating its applicability in determining acceptable levels to avoid formation of stable emulsions. Attenuation measurements provided a clearer illustration of water separation process in various emulsions compared to volume measurements, with observed attenuation effects linked to emulsion system rheology.