Effect of froth stability on dewatering of coal flotation concentrates

This study was conducted to investigate the effect of froth stability on coal filtration and dewatering characteristics by comparing the filtration and dewatering responses of flotation concentrates and unfloated coal slurries. The results show that high froth stability originating from a flotation process has a negative impact on the filtration and dewatering of flotation concentrates. In this study, the flotation of fine coal using saline water produced a highly stable froth with a high air recovery resulting in a short cake formation time and a high final cake moisture content when the flotation concentrate was dewatered. The air bubbles entrained in the flotation concentrate blocked and resisted the flow of water during filtration and dewatering. The moderately and weakly stable froths produced from the flotation of fine coal using deionised water and coarse coal using saline water respectively did not affect the filtration and dewatering process