Study on Breakage Mechanism in the Swirl Generating Stage of an Oil-Water Separator for Marine Oil Extraction and Its Verification

High-efficient oil-water separator is badly-needed in marine oil extraction. Droplet breakage is common during the conversion from pipe to swirl flow in separators. Avoiding oil droplets break into small ones in the swirl generating stage is beneficial to improve the separator's separation efficiency. Information regarding the breakage mechanism and dispersed droplet distribution is critical for optimum design of the conversion structure, such as guiding vanes and prediction of the oil-water separation performance. However, little work has been related to the study of droplet sizes in a swirl flow produced by guiding vanes. The present work focuses on the oil droplet sizes generated by the passage of oil-water mixture goes through guiding vanes in a vane-type separator and the different breakage mechanism. Experiments were performed under different flow rates and maximum droplet sizes were measured in situ downstream from the guiding vanes. The maximum droplet size was found to fit a modified-T model. Besides, Modified-T model was found to fit different studies data the best in the noncoalescence system. The studies shows that reducing the energy loss also reduces the probability of droplet breakage which put forward a new method to improve the separator's design