An Experimental Study on the Application of Ultrasonic Technology for Demulsifying Crude Oil and Water Emulsions

Abstract

An emulsion is the mixture of two immiscible fluids, where one fluid appears as droplets within another. In the oil and gas industry, produced crude oil generally comes with an appreciable amount of water within it in an emulsified form. Before produced crude oil can be prepared for purchase, the water associated with it must be removed. A process known as demulsification is required in order to separate an emulsion into its two phases. In the industry, a number of demulsification techniques are already present; these include thermal, mechanical, chemical, and electrical techniques.Crude oil and gas produced from wells originally come with water, salts, and volatile gases such as oxygen, carbon dioxide, and sometimes hydrogen sulfide, etc. Hence, the petroleum mixture needs to be refined-water, salt, and non-hydrocarbon gases to be separated from the mixture, in order to meet certain oil and gas specifications (which state the maximum concentrations of such contaminants) and make it ready for purchase and transportation.Sonication provides a cheap, simple, and harmless (as it involves mainly the propagation of sound waves) way of separating crude oils from water droplets via demulsification. In addition, if needed, it can be used for emulsification processes as well. Hence, a study of sonification as a way for crude refinement or chemical mixing has important implications for the oil and gas. This investigation proposes the use of ultrasonication as a new and cost-effective technique to aid in the demulsification of crude oil emulsion. The effectiveness of this technique was gauged through its comparison to the already present methods in the industry. Based on the investigation it was found that centrifuge served as the best demulsification method for it reduced the turbidity by 86%. In addition, the reduced turbidity achieved with proposed ultrasonication method ranges from 20%-60%.

Water-in-Oil Emulsions Separation Using a Controlled Multi-Frequency Acoustic Field at an Operating Facility

“…There are a large number of methods for separating stable water-in-oil emulsions, however, the most promising by most researchers are physical methods and, in particular, the use of electromagnetic effects of high (HF) and ultrahigh frequency (microwave) waves. Ultrasonic exposure should also be attributed to effective methods in terms of minimizing power consumption [5,6]. This fact was confirmed as a result of the authors' field tests.…”

“…Recently, the application of physical methods for the separation of stable water-in-oil emulsions has been studied very actively [2][3][4]. Considering peculiarities of applications of electromagnetic influence of waves of high (HF) and ultrahigh frequencies (UHF), the most common, in terms of low values of power consumption, has been determined as ultrasonic influence [5,6]. The materials presented in this article have the following structure.…”

Magnetically recoverable magnetite-reduced graphene oxide as a demulsifier for surfactant stabilized crude oil-in-water emulsion

“…In demulsification test, the proper dosage of demulsifier for the demulsification of crude O/ W emulsion should be determined. This is due to a very low dosage of demulsifier leaves the emulsion unchanged, but an excessive amount of demulsifier may produce a stable emulsion [51]. Thus, the effect of demulsifier dosage on demulsification efficiency (E D ) or oil removal rate was investigated in this study.…”

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.…”