Froth Flotation Cells
Froth Flotation Cells are effective for the beneficiating of fine coal <0.5mm.
Operation
Fine coal can be separated from shale and other waste by using a process including froth flotation cells.
The coal is made water repellent by the addition of a reagent such as oil, so that when a suspension of coal is agitated with air it sticks to the air bubbles and floats to the surface, collecting as froth.
Shale and other waste are not wetted by the reagent due to the different nature of their surface and hence do not stick to the bubbles and remain in the suspension to be drawn off the froth flotation cells at a controlled rate, the froth is removed from the upper cell weir by the assistance of rotary paddles.