Froth stability of coal flotation in saline water

The objective of this study was to identify a practical solution to mitigating over-stable froth problems in fine coal flotation in saline water. The effect of coal particle size, water quality and chemical reagents which can be manipulated in flotation plants, on the froth stability and coal flotation performance was investigated. It was found that froth stability was dependent on the coal particle size, the proportion of process water mixed with de-ionised water and the dosage of the collector or frother. Mixing coarse coal particles with fine coal, diluting process water, and reducing collector or frother dosage all significantly decreased the froth stability. However, only the reduction of reagent usage was recommended as a sound strategy since it did not negatively impact the coal flotation performance while eliminating the over-stable froth problems.