Intensification of ultrasonic-assisted crude oil demulsification based on acoustic field distribution data

Abstract

Water removal is an essential step during crude oil production due to several problems such as increased transportation costs and high corrosion rate due to dissolved salts. Indirect low frequency ultrasonic energy (US), using baths, has been recently proposed as an effective alternative for crude oil demulsification. However, the reactor position during sonication and its influence on the demulsification efficiency for crude oil has not been evaluated. In this sense, the aim of this study was to develop an automated system based on an open source hardware for mapping the acoustic field distribution in an US bath operating at 35kHz using a hydrophone. Data acquired with this system provided information to evaluate the demulsification efficiency in the different positions of the US bath and correlate it with the acoustic intensity distribution. The automated 3D-mapping system revealed a higher acoustic intensity in the regions immediately above the transducers (ca. 0.6Wcm), while the other regions presented a relatively lower intensity (ca. 0.1Wcm). Experimental data demonstrated that reactors positioned in the most intense acoustic regions provided a much higher efficiency of demulsification in comparison with the ones positioned in the less intense acoustic field regions. Demulsification efficiency up to 93% was obtained with 15min of sonication (100% amplitude) using few amount of chemical demulsifier. Hence, this work demonstrated that the information acquired with the developed mapping system could be used for inducing a higher efficiency of demulsification only by finding the more suitable position of reactor in the US bath, which certainly will help development of appropriate reactors design when looking for such approach.

An ultrasound‐assisted sample preparation method of carbonatite rock for determination of rare earth elements by inductively coupled plasma mass spectrometry

“…Experiments for USAE were performed with an ultrasound bath, an ultrasound probe or a cup horn system coupled to an ultrasonic processor. Each system was set to allow better incidence of ultrasound, following previous work . The operational parameters of the ultrasound systems are shown in Table .…”

An Overview of Recent Advances in State-of-the-Art Techniques in the Demulsification of Crude Oil Emulsions

“…At a frequency of >45 kHz, there was no evidence of crude oil demulsification. In the work of Pedrotti et al [150], a demulsification efficiency of up to 93% was attained at 15 min of sonication (100% amplitude). Pedrotti et al [150] proposed the use of indirect low-frequency ultrasonic energy for the demulsification of crude oil.…”

“…In the work of Pedrotti et al [150], a demulsification efficiency of up to 93% was attained at 15 min of sonication (100% amplitude). Pedrotti et al [150] proposed the use of indirect low-frequency ultrasonic energy for the demulsification of crude oil. The results showed that a higher demulsification efficiency (up to 93%) was attained in the most intense acoustic regions compared with that positioned in the less intense acoustic field regions.…”

Research status and analysis of stabilization mechanisms and demulsification methods of heavy oil emulsions

“…Therefore, it is generally believed that the ultrasonic treatment time is controlled within 30 minutes; the longer the sedimentation time, the more dehydration effect, but as time goes on, the trend of increasing dehydration rate is gradually decreasing. [77][78][79][80] Antes et al 81 carried out a demulsification test on heavy oil emulsions with water content of 12%, 35%, and 50% at frequencies of 25,35,45,130,582,862, and 1146 kHz, respectively. When the frequency is lower than 45 kHz, indirect application of ultrasonic waves can cause instability of the W/O emulsion, and demulsification is observed in a short time (15 minutes) and a relatively low temperature (45°C), which is attributed to ultrasonic cavitation caused by ultrasonic cavitation, leading to an increase in mechanical effects and destroying the stress balance at the interface film.…”

“…However, as the ultrasonic treatment time increases, the dehydration rate is almost unchanged. Therefore, it is generally believed that the ultrasonic treatment time is controlled within 30 minutes; the longer the sedimentation time, the more dehydration effect, but as time goes on, the trend of increasing dehydration rate is gradually decreasing 77–80 . Antes et al 81 carried out a demulsification test on heavy oil emulsions with water content of 12%, 35%, and 50% at frequencies of 25, 35, 45, 130, 582, 862, and 1146 kHz, respectively.…”