High aerating open flow type flotation for effective aeration
- Open flow tank with intermediate and discharge boxes
- Near bottom located impeller/diffuser
- Separate source of low pressure air
- Level control by weir or dart valves (automatic as option)
- Recirculation well
- Reversible impeller direction of rotation
- Max cell size 14 m3
- Increases effective aeration through supercharging
- Maintains solids in suspension by vertical recirculation of pulp
- Pulp-air mixture ejected by impeller over entire bottom of cell, lifts and suspends solids
- Draws large volumes of pulp from upper zone to break up any concentration of sands at the bottom of the cell
DR Flotation machines overview
The Metso DR flotation machine is the first mechanical open type machine to incorporate a vertical circulation of pulp, made possible by combining a “recirculation well” with the distinctive top feed impeller.
This arrangement provides positive vertical circulation of pulp similar to the action in a propeller agitator. Pulp from an intermediate zone of the cell is circulated down into the eye of the impeller, mixed with air, and diffused out over the entire bottom of the cell,
creating a uniform upward current.
This principle varies from most other mechanical open type cells which circulate pulp by lifting it up from the bottom of the cell into the centre of a rotating element.
DR flotation machines process description
- It incorporates vertical circulation of pulp by combining a "recirculation well" with distinctive Metso top feed impeller. This arrangement provides positive vertical circulation of pulp.
- In a cell-to-cell type flotation machine the sanding problem is minimised, as the pulp is 100% mixed in every cell as it passes through the feed pipe and impeller.
- The DR principle of vertical recirculation of pulp effectively minimises stratification and sanding.
- Metso Minerals DR Flotation machines are now available in capacities up to 42.5 m3 (1500 cubic feet) per single mechanism.