Angular particle - Bubble attachment mechanism in flotation

Mineral processing must go through several stages of processing, before entering the separation process (flotation). Flotation is a separation particle process by utilizing hydrophobic and hydrophilic properties of the particles. In the flotation process, the bubbles move to the surface of water to collide with the particles, which move from the surface to the bottom so that the bubble-particle interaction will occur. Hydrophobic particles will be attached to the bubbles and brought up separately from hydrophilic particles or tailings that also fall to the bottom. The bubble-particle interaction mechanism is not well understood so far. Thus, it becomes an important field for research. This study aims to understand the interaction mechanism between bubbles and non-sphere-shaped particlescoming from mining, in contrast with the previous studies that used sphere-shaped particles. The experimental setup consists of a flotation tank, a bubble generator, a high-speed video camera, a particle feeder, and an image processing software. Results of the study were achieved, namely the time for particles sliding on the surface of the bubbles. The particle size affects the bubble particle interaction. The particle size of 38μm moves quickly to follow the streamlines at the surface of the bubbles and form a stable aggregate. While big particles with a size of 300 μm are predominantly influenced by the gravity force, when they collide with the surface of the bubbles, they will slide along the surface of the bubbles and then bounce off the surface leaving the bubbles, and they fail to form a stable aggregate.