Ultrasound wave stimulation at the hot separation stage has been considered as a promising method to improve hydrogen sulfide removal from crude oil. Application of ultrasound waves has proved effective in various industries and has been used for an appreciable length of time now to achieve different goals, in that number, to improve dispersion, dissolving, impregnation, cutting, bonding, and welding of different materials and media. Numerous experiments have shown that ultrasound waves improve the process of desorbing of water-dissolved gases, however literature about ultrasound waves used for gas removal, in particular, hydrogen sulfide removal from crude oil, is scarce. The efficiency of ultrasound wave stimulation of the hydrogen sulfide stripping process is controlled by physicochemical properties of the treated medium, pressure and temperature conditions, exposure time, sound wave power, ultrasound intensity and frequency. The experiments demonstrated that in oils with viscosities over 400 mPa·s, specific sound wave power increase has little, if any, effect on effectiveness of hydrogen sulfide stripping, while in oils with viscosities below 150 mPa·s, increase of the sound wave power from 100 to 200 W/dm3 enhances hydrogen sulfide removal twofold. The same tendency was observed for the ultrasound wave frequency. Increase of sound wave power and exposure time improves the hydrogen sulfide stripping process. This is especially true for lower-viscosity oils. Albeit considerable reduction of hydrogen sulfide in crude oil, increase of the sound wave power is not entirely worthwhile. A relationship between exposure time and oil viscosities in the range between 40 and 415 mPa·s has been offered. The ultrasound technology can be used to full advantage at oil treatment facilities reducing consumption of hydrogen sulfide chemical scavenger.
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