Effect of vibration mode on detachment of low-rank coal particle from oscillating bubble

Abstract

As a sub-process of flotation, the bubble-particle detachment plays a critical role in final flotation recovery. In this short communication, the effect of vibration mode, i.e., sine wave, triangle wave and square wave, on the detachment of low-rank coal particle from oscillating bubble was investigated using a home-made bubble-particle detachment measurement system. The critical detachment amplitude was used to evaluate the stability of bubble-particle aggregate. Three coal size fractions, i.e., 0.25–0.5, 0.5–1, and 1–1.5 mm, were used as the experimental samples, respectively. The results show that the critical amplitude decreased as particle size increased under different vibration modes due to the increased inertia. The critical amplitude at three different size fractions always decreased in the following order: sine wave, triangle wave and square wave, indicating the bubble-particle aggregate was the most stable under sine wave vibration. Square wave vibration has the most dramatic movement path changes, causing a highest instantaneous impulse and detachment force.