A novel method for measuring film thickness of oily bubbles and its effect on attachment time in oily-bubble flotation

Abstract Oily-bubble flotation technology has been proven to be an effective separation method for low rank/oxidized coals, and difficult-to-float minerals, in which oily bubbles as a carrier replacing air bubbles are the key. This study proposed a novel method for measuring the film thickness of oily bubbles, which is based on the light interference combining with an ultraviolet light spectrophotometer. Moreover, the effect of oil film thickness on the mineralization was investigated with an induction time instrument. The results indicated that the increase in oil film thickness caused the decrease in attachment time, and was thereby conducive to the attachment of the coal particles on oily bubbles. This work may enrich the knowledge in the branch of coal flotation.