Direct bubble size measurement in a mechanical flotation cell by image analysis and laser diffraction technique - A comparative study

Froth flotation is one of the most widely used methods to separate minerals. Although the bubble size of froth is a critical factor which affects the separation efficiency, accurate measurement of bubble size in a flotation cell brings its own challenges. Accordingly, in this study, the size distribution of the bubbles which were produced in a mechanical flotation was determined by both a new step-up system and the authentic laser diffraction (LD) technique. Image analysis (IA) as a typical technique for measuring bubble sizes was applied to validate the accuracy of the LD measurements and to compare the results. IA and LD outcomes in various bubble generation conditions were in a good agreement. Results revealed that LD technique is relatively faster, easier, and more accurate than IA. Therefore, measuring bubble size by LD can be considered as a reliable, alternative method to IA to determine the bubble sizes in different conditions in a mechanical flotation cell.