Effects of particle wettability and water moisture on separation efficiency and drop size distribution of particle-laden droplets in oil

Abstract

Solid/oil separation is widely used in various industrial fields. Conventional methods can effectively separate solids with large particle sizes from oil media; however, removing fine solids using these methods remains challenging. Researchers have attempted to remove fine particles by applying wettability modification, interface capture, and sedimentation, but these methods have several disadvantages and exhibit low efficiency. The relationship between wettability, solid removal rate, and drop size distribution variation of particle-laden droplets remains unclear. Herein, we propose the application of a centrifugal field to enhance the water-based “forth flotation” and investigate its separation characteristics experimentally. Separation experiments under gravity and centrifugal conditions were performed, and the sedimentation of particle-laden droplets dispersed in oil was conducted. The effects of wettability and initial water moisture on separation efficiency were explored, and the solid/oil separation mechanism was analyzed. The variation in the drop size distribution under different conditions was evaluated, and a mathematical relation for predicting the initial average drop size of particle-laden droplets was fitted. In addition, the fitted mathematical expression can be utilized to predict the initial average drop size of particle-laden droplets.