Separation characteristics and structure optimization of double-field coupling demulsifier with composite curing cone

Abstract In the fields of oilfield exploitation and petrochemical industry, demulsification and dewatering is one of the key processes in the resource utilization of emulsion. The device embedded with high-voltage electric field can achieve efficient demulsification and dewatering treatment, but the cone structure of the device has a great influence on the flow field. Therefore, a new double-field coupling dewatering and purification device with a composite curve–cone structure is proposed through the design and optimization of the device's cone structure. The mixture model was used to simulate the multiphase flow, the computation fluid dynamics (CFD) and population balance model (PBM) were used for numerical calculation in Fluent, and the optimal structure is obtained by combining the Box–Behnken factor design and the response surface method. Furthermore, the flow field and separation characteristics of the new structure and traditional structure are compared. Results show that when the structural parameters a, b and Ro are 110, 4, and 9 mm, respectively, the new coupling device has a high separation efficiency, which is approximately 97.03%. The separation efficiency of the new structure is 6.68% higher than that of the traditional structure. The composite curve-cone coupling device is more beneficial to the oil-water separation.