Flotation separation device and method

A method of flotation separation for partitioning a slurry in a flotation separation system, the flotation separation system including a flotation separation cell, the flotation separation cell including a sparger unit and a separation tank, the sparger unit including a sparging mechanism that a substantially vertically oriented sparging mechanism housing having a separate inlet for a slurry inlet and a gas inlet at a first portion of said sparger mechanism housing and a slurry-gas mixture outlet at a second portion of said sparger mechanism housing, said sparger mechanism further comprises a rotating high-shear element within said sparging mechanism housing between said first portion and said second portion element, the effective open area in the sparging mechanism is substantially the same as the effective open area in the sparger unit upstream and downstream of the sparging mechanism, the sparging mechanism is configured such that slurry flow through it is substantially unrestricted, the rotating high-shear element for breaking up gas bubbles to increase the cumulative surface area of the gas bubbles, the slurry including a hydrophobic species which can adhere to gas bubbles formed in the slurry, said flotation separation method comprising:

• introducing a slurry into the sparging unit;
• introducing gas into the slurry in the sparging unit with at least enough pressure to form bubbles in the slurry;
• sparging the gas in the slurry into a bubble dispersion with the sparging mechanism at a pressure in the sparging mechanism of about 10 psig or less, and subjecting said slurry and introduced gas to said rotating high-shear element to break up said introduced gas into finer gas bubbles;
• and
• discharging the slurry and the bubble dispersion from the sparger unit to the separation tank and allowing the bubble dispersion to form a froth at the top of the slurry contained in said separation tank.