Research Of Enhancing CO₂ Desorption From Crude Oil Of CO₂ Flooding By Ultrasound

After gas channeling during CO₂ flooding,CO₂ gas content in the produced liquid will gradually increase.In the design of gas-liquid separator,in order to achieve the effective desorption of CO₂ gas,the retention time of produced liquid in gas-liquid separator has to be prolonged appropriately just based on the experience,which is not often effective,subsequently leading to serious corrosion of the equipment.In this paper,the study key point is the desorption law of CO₂ in crude oil under the conditions of ultrasonic enhancement.The ultrasonic-enhanced CO₂ desorption from CO₂ flooding crude oil experimental equipment is designed and built,and the method of step-down desorption is adopted.In the condition of gathering temperature and pressure,gas desorption process of the crude oil in gas liquid separator is simulated,and then the relation of CO₂ desorption rate and desorption percentage with time is determined.Finally,the desorption rule of CO₂ in crude oil is obtained under the conditions of ultrasonic enhancement.Experiments are conducted to study how ultrasound enhances desorption of CO₂from crude oil.It is found clearly that only relying on the conventional step-down desorption and prolonging stay of crude oil in the separator cannot solve the practical problem of effective desorption of CO₂,and using ultrasound can enhance CO₂desorption from crude oil.An analysis of ultrasonic influence on the desorption rate and the percentage of CO₂ desorbed reveals the phenomena and variation rules of desorption peaks,second peaks,oil bubbling and power threshold.