Experimental Studies On Demulsification Of Produced Liquid Containing Heavy Oil By Sonochemical Treatment

It is difficult for the demusification of produced liquids containing heavy oil by conventional methods because of its higher viscosity and density. Sonochemical treatment is a new method for the demulsification of produced heavy crude oil. However, it is very urgent to explore the mechanisms of sonochemical treatment.On the basis of demulsification of produced liquids by free setting and chemical treatment, the effect of ultrasonic treatment on produced liquids demusification was evaluated and the influencing factors including ultrasonic power, treating time and temperature on the dewatering rates were analyzed. Experimental studies of the demusification by sonochemical method were conducted and compared with that of free setting, chemical treatment and ultrasonic demusification.Experiments show that more and more water can be separated from the heavy oil produced liquids during the time of ultrasonic treatment and the dewatering rate increases. The final dewatering rate increases with the increase of ultrasonic power, treating time and dewatering temperature. The factors influencing the dewatering rate of ultrasonic treatment are in the order of treating time, dewatering temperature and ultrasonic power according to orthogonal tests. The optimum experimental conditions for ultrasonic dewatering are ultrasonic power in 150W, treating time in 30min, dewatering temperature at 70℃. The dewatering rate increase greatly by sonochemical treatment compared with free setting, chemical demusification and ultrasonic dewatering, especially at lower dewatering temperature. The final dewatering rate increases with the increase of ultrasonic power, treating time, dewatering temperature and the concentration of demulsifiers. The dewatering temperature and the concentration of demulsifiers can be decreased by sonochemical treatment to achieve the same final dewatering rate, compared with ultrasonic treatment and chemical demusification. The factors of ultrasonic power, treating time, dewatering temperature and the concentration of demulsifiers can be combined to achieve the same final dewatering rate. The water-cut in the dewatered heavy oil is less than 1% after sonochemical treatment. After all, sonochemical treatment can decrease the dewatering temperature and the concentration of demulsifiers to achieve the goal of energy saving and environmental protecting.