CA-3221478-C - MEMBRANE SPARGERS FOR GRAVITY SEPARATORS AND FLOTATION MACHINES

CA3221478CCA 3221478 CCA3221478 CCA 3221478CCA-3221478-C

Abstract

A separator device (100) includes a separation chamber (107) defined at its lower end by a fluidization fluid panel (111). The separation chamber (107) receives incoming slurry (113) via a slurry inlet (102). The separator device may be characterised in that means (122) for supplying pre-sheared aerated fluidization fluid is provided above the fluidization fluid panel (111). The means (122) for supplying pre-sheared aerated fluidization fluid includes a novel sparger (119) comprising a flexible perforated membrane which is configured to supplementally shear the pre-sheared aerated fluidization fluid and uniformly distribute microbubbles (129) throughout the separation chamber (107).

Inventors

Jacob Parrott
Thien Sok
Lance Christodoulou
Joon Won LEE

Assignees

FLSMIDTH A/S

Dates

Publication Date: 20260505
Application Date: 20220527
Priority Date: 20210527

Claims (4)

90812600 CLAIMS: 1. A separator device comprising: 33 a separation chamber defined at a lower end by a fluidization fluid panel, and being defined on sides by a tank wall; a lower outlet provided at a lower end of the separator device and extending downwardly through a central region of the lower fluidization fluid panel; a launder provided at an upper end of the separator device; a slurry inlet for receiving incoming slurry into the separation chamber; wherein the separator device further comprises means for supplying pre-sheared aerated fluidization fluid to the separation chamber above the fluidization fluid panel, said means including: i.) a sparger provided above the fluidization fluid panel and comprising a flexible perforated membrane, and, ii.) a shearing device selected from the group consisting of: a static inline mixer, a cavitation tube, a cavitation nozzle, and a chaos mixer; wherein the shearing device is configured for producing the pre- sheared aerated fluidization fluid by passing a mixture of combined fluidization fluid and gas through the shearing device.
2. The separator device according to claim 1, wherein the sparger is configured as one of the group consisting of: a straight tube, a curved tube, a coil, a disc, a puck, a panel, and a plate.
3. The separator device according to claim 1 or 2, wherein the sparger has ends, and the sparger is fed at one of the ends with the pre-sheared aerated fluidization fluid.
4. The separator device according to any one of claims 1-2, wherein the sparger has ends, and the sparger is fed at both of the ends with the pre-sheared aerated fluidization fluid. 90812600 5. 34 The separator device according to any one of claims 1-4, further comprising a plurality of said sparger . 6. The separator device according to claim 5, wherein each of the plurality of said sparger are at least one of nested and packed together. 7. The separator device according to claim 5 or 6, wherein each of the plurality of said sparger are of different sizes or shapes. 8. The separator device according to any one of claims 5-7, wherein each of the plurality of said sparger are oriented differently in space with respect to components of the separator device. 9. The separator device according to any one of claims 1-8, wherein the sparger is horizontally-arranged. 10. The separator device according to any one of claims 1-9, wherein the sparger is inclined so as to follow an angle of the fluidization fluid panel. 11. A method for separating particles within an incoming slurry using the separator device according to any one of claims 1-10, comprising the steps of: providing the separator device according to any one of claims 1-10; combining a gas with a fluidization fluid using the shearing device; shearing the combined gas and fluidization fluid a first time using the shearing device to produce a first sheared aerated fluid; passing the first sheared aerated fluid through the sparger; shearing the first sheared aerated fluid a second time through openings or perforations extending through the flexible perforated membrane of the sparger to produce a twice-sheared aerated fluid; 90812600 35 uniformly distributing fine bubbles within the twice-sheared aerated fluid throughout the separation chamber of the separator device; segregating particles within the separation chamber based on their size, density, hydrophobicity, or mineral composition; and, removing the segregated particles via the launder and lower outlet. 12. The method according to claim 11, further comprising the step of: intermittently or periodically boosting the pressure or flow of the first sheared aerated fluid provided to the sparger; expanding or flexing the flexible perforated membrane by virtue of boosting the pressure; allowing the openings or perforations extending through the flexible perforated membrane of the sparger to expand, and thus allow the first sheared aerated fluid provided to the sparger to pass therethrough at least one of an elevated velocity and energy; and clearing obstructions or dislodging one or more particles from the openings or perforations extending through the flexible perforated membrane of the sparger by virtue of at least one of the elevated velocity, energy and by virtue of expansion of the openings or perforations extending through the flexible perforated membrane of the sparger. 13. The separator device according to any one of claims 1-10 further comprising an upper segment, a middle segment, and a lower segment collectively forming a tank wall of the separator device; wherein the middle segment comprises an aeration insert having one or more of the sparger provided thereto.

Description

WO 2022/249144 PCT /IB2022/055014 1 MEMBRANE SPARGERS FOR GRAVITY SEPARATORS AND FLOTATION MACHINES FIELD OF THE INVENTION Embodiments of the present invention pertain to improvements to gravity separation and flotation machines, in particular, "rotorless" gravity- and fluidized 1 o bed-assisted flotation apparatus. In particular, embodiments of the present invention relate to a unique flexible perforated membrane sparger for optimizing bubble size distributions within a fluidized bed and/or facilitating periodic sparger purging. Embodiments may further include a method involving the dual-shearing of aerated fluidization fluids. BACKGROUND OF THE INVENTION Reference to background art herein is not to be construed as an admission that 2 o such art constitutes common general knowledge in the arts. In many industrial processes, fluidized beds are used to suspend solids and perform various separations within equipment. An example of such device can be found in US Pat. No. 6,814,241 B1. Another example can be found in the 25 FLSmidth® REFLUX® classifier, a specialized gravity-assisted separation device. Turning now to FIGS. 1-3, such conventional separator devices 1 may incorporate a vertically-oriented separation chamber 7 defined by a tank wall 3. The separation chamber 7 may be fed with incoming slurry 13 at its upper region via a slurry inlet 3 o 2. The separation chamber 7 may be defined at its lower end by a fluidization fluid panel 11 which may be provided with openings 10 (e.g., perforations, slots, orifices, or nozzles). Incoming fluidization fluid 12 may be received by a fluidization fluid inlet 4 and subsequently delivered to a lower fluidization fluid distribution chamber 8 defined at its upper end, by the fluidization fluid panel 11. The fluidization fluid 35 panel 11 separates the fluidization fluid distribution chamber 8 from the separation WO 2022/249144 PCT /IB2022/055014 2 chamber such that the openings 10 therein allow fluidization fluid to pass from the fluidization fluid distribution chamber 8 upwardly through the panel 11 and into the separation chamber 7. Thus, the two chambers 7, 8 fluidly communicate with one another, wherein contents within the separation chamber 7 are prevented or 5 discouraged from backflowing into the lower fluidization fluid distribution chamber 8. Solids within the incoming slurry 13 are separated by gravity, wherein finer or lessdense particles are discharged at an upper portion of the device 1 by passing over 1 o a weir 16 (as overflow 15), and entering into a collection launder 17. Coarser or denser particles fail to move upward within the separation chamber 7 and end up being discharged through a lower outlet 9 passing through a central opening in the fluidization fluid panel 11. The coarser or denser particles pass through/by the fluidization fluid distribution chamber 8 and exit the bottom of the device 1 (as 15 underflow 14). An upper separation chamber 6 may be provided between the weir 16 and the separation chamber 7, and this upper separation chamber 6 may comprise a number of lamellae or spaced (e.g., parallel) inclined plates 5 to improve 2 o separations. By adjusting flows of incoming slurry 13 and fluidization fluid 12, separations can be optimized for a particular process. Similar units may be designed for use for flotation, in addition to, or in lieu of classification. An example can be seen in WO 2020152651 A1, where the 2 s incoming fluidization fluid 12 is aerated within the fluidization fluid distribution chamber 8 prior to passing through the fluidization fluid panel 11 and into the separation chamber 7. Bubbles within the separation chamber 7 combine with hydrophobic particles and move upwardly where they eventually make their way to the collection launder 17 as froth overflow 15. Hydrophilic particles fail to bind 3 o with the bubbles within the separation chamber 7 and eventually make their way to the lower outlet 9 as underflow 14. WO 2022/249144 PCT /IB2022/055014 3 A problem with such devices, is that the openings 10 in the fluidization fluid panel 11 (e.g., orifices extending through panel 11 ), can clog and/or may not adequately provide controlled bubble size distributions, uniform bubbly zones, or fine bubble size adjustments within the separation chamber 7. Openings 10 comprising a large 5 number of nozzles or spargers provided to the fluidization fluid panel 11 can significantly increase manufacturing costs and total time to fabricate and service. Nozzles and spargers provided to fluidization fluid panel 11 can also clog over time and may be difficult to purge without removal. 1 o Embodiments of the present invention aim to improve upon existing gravity separation apparatus and fluidized bed-assisted (i.e., "rotorless") flotation machines by incorporating low-cost flexible perforated membrane structures which synergistically work together to provide a more homogeneous bubble size distribution, more uniform introductions of aerated fl