Understanding copper flotation in the JKHFmini: A small-scale fluidised bed cell

• JKHFmini demonstrates reproducible overall copper recovery with gangue rejection. • Copper recovery increases with airflow but plateaus at elevated air rates. • Excessive water flow promotes gangue elutriation. • JKHFmini reasonably predicts true flotation in coarse sizes compared to full-scale. • JKHFmini shows higher mass recovery than full-scale due to high gangue elutriation. Laboratory batch flotation testing on small samples in conventional cells, such as the Denver flotation cell, is well-established and standardised. On the other hand, the JKHFmini, a newly developed small-scale fluidised bed flotation cell, requires testing to validate and understand the factors affecting its operation. This work aims to elucidate how the operating variables of the JKHFmini affect flotation performance and compare the flotation outcomes to those obtained in a full-scale HydroFloat® unit. Flotation tests were performed using a factorial experimental design and conducted in parallel with surveys of a full-scale HydroFloat® circuit. The results show that increasing the water flow rate during operation improved copper recovery, but excessive water flow caused unselective gangue recovery. Recovery also increased with airflow but plateaued beyond an optimal point. The JKHFmini demonstrated good repeatability with preferential recovery of copper over gangue, particularly in the coarser size fractions. The JKHFmini produced copper recoveries of similar magnitude compared to the full-scale HydroFloat®, although the mass recoveries obtained in the JKHFmini were significantly higher due to enhanced elutriation of fine particles. These findings suggest the JKHFmini may be a useful tool for assessing true flotation performance in coarse particle flotation systems, although differences in elutriation must be considered when scaling to the performance in full-scale systems.