Removal of oil from synthetic heavy crude oil-in-water emulsions by the association of glass raschig rings and ultrasound

Numerical assessment of ultrasound supported coalescence of water droplets in crude oil

In this study, a numerical assessment of the coalescence of binary water droplets in water-in-oil emulsion was conducted. The investigation addressed the effect of various parameters on the acoustic pressure and coalescence time of water droplets in oil phase. These include transducer material, initial droplet diameter (0.05-0.2 in), interfacial tension (0.012-0.082 N/m), dynamic viscosity (10.6-530 mPas), temperature (20-100 °C), US (ultra sound) frequency (26.04-43.53 kHz) and transducer power (2.5-40 W). The materials assessed are lead zirconate titanate (PZT), lithium niobate (LiNbO₃), zinc oxide (ZnO), aluminum nitride (AlN), polyvinylidene fluoride (PVDF), and barium titanate (BaTiO₃). The numerical simulation of the binary droplet coalescence showed good agreement with experimental data in the literature. The US implementation at a fixed frequency produced enhanced coalescence (t = 5.9-8.5 ms) as compared to gravitational settling (t = 9.8 ms). At different ultrasound (US) frequencies and transducer materials, variation in the acoustic pressure distribution was observed. Possible attenuation of the US waves, and the subsequent inhibitive coalescence effect under various US frequencies and viscosities, were discussed. Moreover, the results showed that the coalescence time reduced across the range of interfacial tensions which was considered. This reduction can be attributed to the fact that lower interfacial tension produces emulsions which are relatively more stable. Hence, at lower interface tension between the water and crude oil, there was more resistance to the coalescence of the water droplets due to their improved emulsion stability. The increment of the Weber number at higher droplet sizes leads to a delay in the recovery of the droplet to spherical forms after their starting deformation. These findings provide significant insights that could aid further developments in demulsification of crude oil emulsions under varying US and emulsion properties.

The Utilization of Ultrasound for Improving Oil Recovery and Formation Damage Remediation in Petroleum Reservoirs: Review of Most Recent Researches

The ultrasound method is a low-cost, environmentally safe technology that may be utilized in the petroleum industry to boost oil recovery from the underground reservoir via enhanced oil recovery or well stimulation campaigns. The method uses a downhole instrument to propagate waves into the formation, enhancing oil recovery and/or removing formation damage around the wellbore that has caused oil flow constraints. Ultrasonic technology has piqued the interest of the petroleum industry, and as a result, research efforts are ongoing to fill up the gaps in its application. This paper discusses the most recent research on the investigation of ultrasound’s applicability in underground petroleum reservoirs for improved oil recovery and formation damage remediation. New study areas and scopes were identified, and future investigations were proposed.

Base oil recovery from waste lubricant oil by polar solvent extraction intensified by ultrasound

This paper proposes a greener approach to the intensification of base oil recovery for truck engines (32,500 km of use) using ethanol, propan-2-ol, 2-methylpropan-1-ol, and butan-1-ol as solvents for the extraction of base oil, combining mechanical stirring (220 rpm) and ultrasound (25 °C, 24 kHz, and 400 W). The results indicated that the recovery yields of the base oil, using the mechanical stirring and ultrasound (MS-US) system, for ethanol, propan-2-ol, 2-methylpropan-1-ol, and butan-1-ol were approximately 3.1, 25.6, 71.6, and 85.5%, respectively. By contrast, the recovery yields using only mechanical stirring were 8.8, 28.9, 58.9, and 76.1%, respectively. The system with pre-extraction could effectively remove Ca (85.3-93.0%), Mg (67.2-82.9%), Na (31.7-62.5%), and Zn (0.0-71.7%). Finally, the results showed a reduction of almost 100% for the concentrations of Al, Cr, Fe, and Mo in the pre-extraction system. The mechanical stirring (5 min) and ultrasound (5 min) system were able to intensify the extraction process using environmentally friendly solvents.

Application of Cavitation in Oil Processing: An Overview of Mechanisms and Results of Treatment

The integrated effect on homogeneous and heterophase liquids that can be used for technological purposes has drawn the attention of researchers in various sciences. Cavitation impact on oil is among the efficient methods of intensifying chemical-technological, hydromechanical, and mass-exchange processes and the destruction of substances. This work reviews in detail and analyzes the mechanisms of impact and application of cavitation in various processes in the petroleum industry, including the refining processes, that are associated with crude oil and petroleum waste, such as reduction of viscosity, demulsification, desulfurization, and improvement of quality of heavy oil and petroleum refinery products, including oil sludge and waste oil-containing water.