In general, as the fluidization wash water flux increased, the
product ash decreased. This is observed in Fig. 4. However, at the
lower wash fluxes of between 0.1 and 0.5 cm/s, which are more
typical of values used in conventional flotation, there was little,
or no significant reduction in product ash, with values persisting
around 20%. Increasing the fluidization to a moderate flux of 0.8–
1.1 cm/s resulted in a significant drop in product ash to about
12% ash, with the combustible recovery preserved in the range of
27–37%. Using an extreme level of wash water, of 2.1 cm/s, both
the product ash and combustible recovery reduced to levels
matching the Tree Flotation Curve. This demonstrates the effective
desliming and selective stripping of particles achieved by the
downwards flow of fluidization water (Galvin and Dickinson,
2014). Increasing the dose of reagent is observed in Fig. 5 to have
shifted the combustible recoveries significantly higher.