Enhanced Bauxite Recovery Using a Flotation Column Packed with Multilayers of Medium

An innovative self-designed medium was packed in a bench-scale flotation column to study its influence on the flotation recovery of bauxite. Computational fluid dynamics (CFD) simulation was conducted to reveal the impact of the packing medium on the turbulent characteristics of collection zone in the column. Simulation results show that multilayer packing of the medium divides the collection zone into small units having different turbulent intensities, which is more suitable for flotation separation. The packing medium decreases the turbulence kinetic energy (from 1.08 × 10⁻² m²/s² to 2.1 × 10⁻³ m²/s²), turbulence eddy dissipation (from 3.71 × 10⁻² m²/s³ to 9.8 × 10⁻³ m²/s³) and axial fluid velocity of fluid in the column. With three layers of packing, the recovery of Al₂O₃ increased by 2.11% and the aluminum to silicon content ratio of the concentrate improved from 5.16 to 9.72.