Cross-reference to Related Applications

None.

Field of the Invention

Embodiments of the invention relate to a novel fluidized bed separator (e.g., a solid-solid particle classifier) and arrangement for a fluidized bed separator. Embodiments may be especially beneficial when employed in flotation processes - in particular, coarse particle flotation processes.

Background of the Invention

Dissolved air flotation (DAF) processes utilize dissolved air to produce fine bubbles for flota tion in water treatment and oil separation processes. This occurs in open tanks where solids are allowed to settle freely through gravitational forces. Free-settling hydrophobic particles come into contact with air in the form of ultrafine bubbles generated by dissolved air flota tion pumps and associated systems. There are no fluidized beds in such DAF processes.

Coarse particle flotation achieves successful recovery of coarse particles by introducing air into a fluidized bed of particles. Operation utilizing fluidized beds allow for promoting qui escent conditions promoting recovery of coarse particles where hindered settling occurs.

An example from the prior art may be seen in Eriez's froth-free flotation Flydrofloat ^® vessel. Air is introduced into a feed pipe feeding pipe network containing fluidization water and air. and enters the vessel from one side. The air-water mixture enters the fluidized bed from the internal pipe network. Flowever, delivery of aerated solution to the fluidized bed is 'coupled' to the fluidization water rate using such systems. Accordingly, once the aerated solution is provided to the fluidized bed enters the vessel, it cannot be altered or controlled, as it comprises a "one-way" air delivery arrangement.

Turning to prior art FIG. 1, some particle separators 1 (e.g., FLSmidth ^® REFLUX ^® classifier) conventionally use a fluidized bed with no air introduction. Fluidization fluid 12 enters a fluidization fluid distribution chamber 8 located at the bottom of the fluidized bed sepa rator 1, via a fluidizing fluid inlet 4 and passes through a plurality of orifices or openings 11 extending through a fluidized bed panel 10. The fluidized bed panel 10 defines an upper portion of the fluidization fluid distribution chamber 8. Fluid from the fluidization fluid distribution chamber 8 exiting the openings enters a main separation chamber 7 of the separator device 1 and fluidizes a bed of slurry 13 and particles contained therein.

Feed slurry 13 enters the main body 3 of the separator 1 via a feed inlet 2. The slurry 13 mixes with the fluidization fluid 12 entering the main separation chamber 7, wherein some particles from the slurry 13 progress upwards past an inclined plate stack 5 (e.g., a series of diagonally-arranged and spaced lamellae) and into an upper separation chamber 6 comprising. Those particles from the slurry 13 which do not progress to the upper sep aration chamber 6 may return to the main separation chamber 7 (via gravity) or exit an underflow outlet 9 as underflow 14 (e.g., gangue, coarse particles) via gravity. The under flow 9 may be moved to downstream equipment for further processing or holding.

Some particles from the slurry 13 may eventually exit the top of the separator 1 as over flow 15, and pass over a weir 16. In some embodiments (not shown), a simple pipe outlet extending radially-outwardly from main body 3 may take the place of the illustrated weir 16 and launder 17 arrangement. Overflow 15 leaving the upper separation chamber 6 can comprise a froth, fines, or particles meeting a specific target mineralogy. The over flow 15 may be captured in a launder 17 and moved to downstream equipment for further processing or holding.

The present invention aims to improve upon the conventional separator 1 shown in FIG. 1, to enable better particle separations and process control. Objects of the Invention

According to some embodiments, it is desired to provide a particle separator capable of delivering an even, uniform distribution of fine gas bubbles (e.g., air) across the cross- sectional area of a main separation chamber of a fluidized bed separator, above the flu idized bed panel, without limitation.

According to some embodiments, it desired to provide a particle separator capable of introducing air (e.g., in the form of fine (e.g., < 0.5 mm diameter) bubbles) into the fluid ized bed, main separation chamber, and/or upper separation chamber, without disrup tion of the existing fluidized bed structures, without limitation.

These and other objects of the present invention will be apparent from the drawings and description herein. Although every object of the invention is believed to be attained by at least one embodiment of the invention, there is not necessarily any one single embod iment of the invention that achieves all of the objects of the invention.

Brief Summary of the Invention

A fluidized bed separator 100 is disclosed. The fluidized bed separator 100 may comprise a main body 103, a feed inlet 102 for receiving feed slurry 113, a fluidized bed panel 110 forming an upper portion of fluidization fluid distribution chamber 108, a fluidization fluid inlet 104 for receiving fluidization fluid 112 in the fluidization fluid distribution chamber 108, a main separation chamber 107, an upper separation chamber 106, an inclined plate stack 105, an overflow outlet 117, and an underflow outlet 109. The fluidized bed separator may further comprise a plurality of nozzles 122 provided to the fluidized bed panel 110. The nozzles 122 may be configured to deliver a uniform distribution of liquid and fine gas bub bles across the cross-sectional area of the main separation chamber 107 above the fluidized bed panel 110, without limitation.

The fluidized bed separator 100 may comprise a slipstream outlet 124 fluidly connecting the fluidization fluid distribution chamber 108 to a pump 120. The slipstream outlet 124 may be configured for removing slipstream solution 125 from the fluidization fluid distribution chamber 108. The fluidized bed separator 100 may comprise a dissolved gas solution inlet 123 for returning dissolved gas solution 121, 127 back to the fluidization fluid distribution chamber 108 from the pump 120. The fluidized bed separator 100 may comprise at least one gas inlet 119 configured for delivering gas 118 (e.g., air) to the slipstream solution 125 and/or to the dissolved gas solution 121, 127, without limitation.

In some embodiments, the fluidized bed separator 100 may comprise a gas inlet 119 which is configured for delivering gas 118 to the feed inlet 102 to aerate the feed slurry 113 before it enters the main separation chamber 107, without limitation.

In some embodiments, the fluidized bed separator 100 may comprise a gas distribution chamber 128 provided below the fluidization fluid distribution chamber 108. The gas dis tribution chamber 128 may fluidly communicate with the fluidization fluid distribution chamber 108 and may be configured to deliver gas 118 to the fluidization fluid distribution chamber 108. The gas distribution chamber 128 may receive gas 118 from a gas inlet 119, without limitation.

According to some embodiments, the fluidized bed separator 100 may comprise a mani fold 140. The manifold 140 may fluidly connect the dissolved gas solution inlet 123 to the fluidization fluid distribution chamber 108, for example, at multiple entry points 141. The multiple entry points 141 may be circumferentially-spaced around a periphery of the fluid ization fluid distribution chamber 108, without limitation. The manifold 140 may be arcu ate, annular, or C-shaped, without limitation. The manifold 140 may at least partially- (or fully) surround the fluidization fluid distribution chamber 108. The dissolved gas solution inlet 123 may comprise a high shear device or inline mixer 126, such as a static mixer, without limitation. In some embodiments, a high shear device or inline mixer 126, such as a static mixer, may be provided to the slipstream outlet 124, without limitation.

In some instances, nozzles 122 provided to the fluidized bed separator 100 may be config ured to receive gas 118 from a source outside of the fluidized bed separator 100, and flu- ids from the fluidization fluid distribution chamber 108. Such nozzles 122 may be config ured to combine the gas and fluids before delivering the same to the main separation chamber 107.

In some instances, nozzles 122 provided to the fluidized bed separator 100 may be config ured to receive gas 118, such as air, from a source outside of the fluidized bed separator 100 and deliver it (e.g., directly or indirectly) to the main separation chamber 107.

In some embodiments, at least one gas inlet 119 may be provided to the dissolved gas so lution inlet 123 and to the at least one gas inlet 119 provided to the slipstream outlet 124. The underflow outlet 109 may pass through the fluidization fluid distribution chamber 108 and through a gas distribution chamber 128, without limitation.

In some embodiments, the feed inlet 102 may comprise a restricted throat section. A gas inlet 119 may be provided to the feed inlet 102. The gas inlet 119 provided to the feed in let 102 may be configured to deliver gas 118 to the restricted throat section, without limi tation. In addition to, or alternatively to delivering gas 118 to the restricted throat sec tion, a gas inlet 119 may be provided to the feed inlet 102 which is configured to deliver gas 118 to the feed inlet 102 upstream of the restricted throat section, without limitation.

In some embodiments, the gas inlet 119 which is configured for delivering gas 118 to the feed inlet 102 may be configured to aerate the feed slurry 113 before it enters the main separation chamber 107. The configuration may in the form of a cavitation device, a ven turi, an adjustable and/or variable orifice sparging device, a high- or low-shear contacting reactor, or a nozzle 122, without limitation.

A method of operating a fluidized bed separator 100 is also disclosed. The method may comprise the steps of: conveying feed slurry 113 to a main separation chamber 107; con veying fluidization fluid 112 to a fluidization fluid distribution chamber 108; removing overflow 115 from an upper separation chamber 106 via an overflow outlet 117; and re moving underflow 114 from the main separation chamber 107 via an underflow outlet 109, without limitation. The method may further comprise the steps of: conveying slip stream fluid 125 from the fluidization fluid distribution chamber 108 to a pump 120, via a slipstream outlet 124; introducing gas 118 to the slipstream fluid 125 via a gas inlet 119; and/or returning dissolved gas solution 121, 127 to the fluidization fluid distribution cham ber 108, from the pump 120, via a dissolved gas inlet 123, without limitation.

In some embodiments, the step of returning dissolved gas solution 121, 127 to the fluidi zation fluid distribution chamber 108 from the pump 120 via the dissolved gas inlet 123 may include the step of providing the dissolved gas solution 121, 127 from the dissolved gas inlet 123 to a manifold 140. The dissolved gas solution 121, 127 may subsequently be provided from the manifold 140 to the fluidization fluid distribution chamber 108, for ex ample, at multiple entry points 141, without limitation.

In some embodiments, the method comprise the step of conveying a mixture of fluidiza tion fluid 112 and gas 118 to one or more nozzles 122 provided to a fluidized bed panel

110. The method may further include the step of conveying the mixture of fluidization fluid 112 and gas 118 through the one or more nozzles 122 and into the main separation chamber 107.

In some embodiments, the gas 118 may be provided to the fluidization fluid distribution chamber 108 via one or more nozzles 122 fluidly connecting the fluidization fluid distribu tion chamber 108 to a source of gas 118 which is located outside of the fluidized bed sepa rator 100. The gas 118 may be additionally or alternatively provided to the fluidization fluid distribution chamber 108 via one or more gas inlets 119 provided to the dissolved gas solution inlet 123 and/or to the slipstream solution outlet 124. In some embodiments, the gas 118 may be alternatively or additionally provided to the fluidization fluid distribution chamber 108 from a gas distribution chamber 128 provided adjacent to (e.g., below) the fluidization fluid distribution chamber 108, without limitation.

In some embodiments, the method may comprise the step of forming a fluid mixture by combining gas 118 with fluidization fluid 112 and/or dissolved gas solution 121, 127 lo cated within the fluidization fluid distribution chamber 108. The step of combining may be performed using one or more nozzles 122 provided to the fluidized bed panel 110. The resulting fluid mixture may then be conveyed through an upper part 129 of each of the one or more nozzles 122, and through the fluidized bed panel 110 to the main separation chamber 107, without limitation.

In some embodiments, the method may comprise one or more of the following steps: con veying gas 118 to a gas distribution chamber 128; conveying gas 118 from the gas distribu tion chamber 128 to the fluidization fluid distribution chamber 108; allowing the gas 118 introduced to the fluidization fluid distribution chamber 108 from the gas distribution chamber 128 to mix with the fluidization fluid 112 and/or dissolved gas solution 121, 127 within the fluid distribution chamber 108 to form a fluid mixture; delivering the fluid mix ture through the fluidized bed panel 110 and to the main separation chamber 107.

In some embodiments, the step of conveying gas 118 from the gas distribution chamber 128 to the fluidization fluid distribution chamber 108 may involve conveying the gas 118 through one or more nozzles 122 provided to a fluidized bed panel 110 which the gas dis tribution chamber 128 from the fluidization fluid distribution chamber 108.

In some embodiments, the step of delivering the combination of gas 118 and fluidization fluid 112 from the fluid distribution chamber 108 to the main separation chamber 107 may comprise conveying the combination of gas 118 and fluidization fluid 112 through one or more nozzles 122 provided to a fluidized bed panel 110 which separates the fluidi zation fluid distribution chamber 108 from the main separation chamber 107.

In some embodiments, the method may comprise the step of forming a uniform distribu tion of liquid and fine gas bubbles across the cross-sectional area of the main separation chamber 107 above the fluidized bed panel 110, without limitation. The method may also comprise the step of introducing gas 118 to the feed slurry 113 prior to conveying feed slurry 113 to the main separation chamber 107.

In some embodiments, the method may comprise the step of changing a pressure drop of the feed slurry 113 across a restricted throat section of a feed inlet 102 to the fluidized bed separator 100. In some embodiments, the method may comprise the step of increas ing or decreasing shear rate (of the feed slurry 113 or of combined feed slurry 113 and gas 118) to affect bubble sizing of gas 118 introduced to the feed slurry 113. For example, this could be done by adjusting flowrates of feed slurry 113 or gas 118 introduction, or by ma nipulating an adjustable or variable orifice sparger provided to the feed inlet 112, without limitation.

The method may further comprise the step of changing a mixture ratio of gas 118 and fluid 112, 121, 127 entering a nozzle 122 provided to the fluidized bed separator 100, by adjusting a separation distance between an upper part 129 and a lower part 130 of the nozzle 122. Such a nozzle 112 may be provided to the fluidization fluid distribution cham ber 108, or attached to the fluidized bed panel 110, main body 103, without limitation.

The method may, in some embodiments, comprise the step of changing relative flow rates between gas 118 and fluid 112, 121, 127 entering a nozzle 122 provided to the fluidized bed separator 100, for example, by adjusting the pressure of the gas 118 entering the noz zle 122 and/or by adjusting the pressure of the fluid 112, 121, 127 housed within the fluid ization fluid distribution chamber 108.

Description of the Drawings

To complement the description which is being made, and for the purpose of aiding to bet ter understand the features of the invention, a set of drawings illustrating a preferred, non-limiting embodiment of a fluidized bed separator 100 is attached to the present speci fication as an integral part thereof, in which the following has been depicted with an illus trative and non-limiting character. It should be understood that like reference numbers used in the drawings may identify like components.

FIG. 1 shows one example of a conventional fluidized bed separator 1 found within the prior art. FIG. 2 shows an example of a fluidized bed separator 100 according to some non-limiting embodiments of the invention.

FIG. 3 shows a top plan view of a fluidized bed panel 110 and nozzles 122 of a fluidized bed separator 100 according to the view line shown in FIG. 2.

FIG. 4 shows another example of a fluidized bed separator 100 according to some non limiting embodiments of the invention.

FIG. 5 shows yet another example of a fluidized bed separator 100 according to some non limiting embodiments of the invention.

FIG. 6 shows an example in which a manifold 140 may be used to evenly introduce dis solved air solution 121 into a fluidization fluid distribution chamber 108 via multiple entry points 141. As shown, the manifold 140 may surround the body 130 of the fluidized bed separator 100 and may be configured as an annular manifold having multiple entry points 141 without limitation.

FIG. 7 shows yet another example of a fluidized bed separator 100 according to some non limiting embodiments of the invention, wherein a separate air distribution chamber 128 is provided below the fluidization fluid distribution chamber 108 and configured to pro vide air or gas 118 to the fluidization fluid distribution chamber 108.

FIG. 8 shows another exemplary, non-limiting embodiment of a fluidized bed separator 100 having a separate air distribution chamber 128 provided below the fluidization fluid distribution chamber 108.

FIG. 9 shows yet another example of a fluidized bed separator 100 according to some non limiting embodiments of the invention, wherein nozzles 122 of various types may be used in any number, configuration, combination, or permutation, to deliver gas, or a combina tion of gas and fluidization fluid, to the main separation chamber 107. FIG. 10 shows a non-limiting example of a fluidization fluid distribution chamber 108 wherein nozzles 122 may be configured as mixing devices, wherein the nozzles 122 may function by sparging a combination of air (or gas) 118 and fluids received from within the fluidization fluid distribution chamber 108, into the main separation chamber 107. The fluid in the fluidization fluid distribution chamber 108 which is combined with the air or gas 118 may comprise a mixture of fluidization fluid 112, bubbles formed from air or gas 118, and/or dissolved air solution 121, 127 according to some non-limiting embodiments of the invention.

As can more clearly be seen in FIGS. 11-15, during operation, fluid in the fluidization fluid distribution chamber 108 may be drawn through fluid ports 131 in a nozzle 122 and com bined with incoming air or gas 118 passing through tube or port 142. The resulting com bination may be delivered through openings 111 through fluidized bed panel 110 and re ceived by the main separation chamber 107. In some embodiments, air 118 may be drawn into nozzles 122 and through openings 111, facilitated by a pressure differential between fluidization fluid distribution chamber 108 and main separation chamber 107. In some embodiments, air 118 may be drawn into nozzles 122 and through openings 111, facilitated by a pressure differential between air distribution chamber 128 and fluidization fluid distribution chamber 108.

In some embodiments, the fluidization fluid distribution chamber 108 may be maintained at a higher pressure than the main separation chamber 107, without limitation. Air or gas 118 entering nozzles 122 (through feature 142) may be maintained at a higher pressure than the main separation chamber 107. Air or gas 118 entering nozzles 122 (through fea ture 142) may be maintained at a higher pressure than the fluidization fluid distribution chamber 108, without limitation.

FIGS. 11 and 12 show one possible non-limiting exemplary embodiment of a nozzle 122 which might be used in conjunction with a fluidization fluid distribution chamber 108.

FIG. 13 shows another possible non-limiting exemplary embodiment of a nozzle 122 which might be used in conjunction with a fluidization fluid distribution chamber 108. FIGS. 14 and 15 show additional non-limiting exemplary embodiments of a nozzle 122 comprising sealing means 134 at an interface with a fluidized bed panel 110.

FIGS. 16 and 17 show an additional non-limiting exemplary embodiment of a nozzle 122 comprising means 136 for applying torque as well as means 138 for connecting nozzle 122 to an air (or gas) source adjacent a lower part 130 thereof.

FIGS. 18-24 schematically illustrate various methods of optionally pre-contacting incom ing feed slurry 113 with air (or gas) 118 according to embodiments, without limitation.

In the following, the invention will be described in more detail with reference to drawings in conjunction with exemplary embodiments.

Detailed Description

A fluidized bed separator 100 according to preferred embodiments of the invention is shown in FIG. 2.

The separator 100 may comprise a main body 103. The main body 103 is preferably con figured as a substantially vertically-oriented tubular body as shown, such that a central axis (not shown for clarity) of the body 103 extends generally vertically up and down. It is contemplated that the body 103 may be oriented at a slight angle from true vertical, without limitation. The separator 100 may, in some preferred embodiments, be taller in profile than it is wide - and such embodiments may be preferable for reducing footprint area and required floorspace.

The body 103 may comprise a feed inlet 102 near its central or upper area for receiving a feed slurry 113 comprised of particles to be separated. The feed slurry 113 may contain crushed ore, process water, and/or reagent(s), without limitation. As will be described hereinafter, air or gas 118 may be combined with the feed slurry 113 in the feed inlet 102. The feed inlet 102 may be positioned adjacent to a main separation chamber 107, adja cent to an upper separation chamber 106, or somewhere in-between the main 107 and upper 106 separation chambers, as shown, without limitation. The feed inlet 102 prefer ably extends from an outer portion of the main body 103, for example, the feed inlet 102 may extend radially outwardly from the separator 100 at a periphery of the main body 103, and may be configured as a tube with a connection flange at its distal end, without limitation. The feed inlet 102 may extend radially outwardly from a tubular wall portion of the separator 100 body 103 as shown. The separator 100 may take on various cross- sectional shapes - including those having polygonal and circular profiles, without limita tion. In the particular embodiment shown, the main body 103 of the separator is cylin drical.

At the bottom of the separator 100, and adjacent a lower portion of the body 103, a flu idization fluid distribution chamber 108 is provided. Feeding the fluidization fluid distri bution chamber 108 is a fluidizing fluid inlet 104 which is configured to receive fluidizing fluid 112 at a predetermined flowrate and/or pressure. Fluidizing fluid 112 may be pe ripherally received through the inlet 104 as shown, wherein the fluidizing fluid inlet 104 extends radially outwardly from body 103 and away from fluidization fluid distribution chamber 108, without limitation. While not shown, the fluidizing fluid inlet 104 may al ternatively enter the fluidization fluid distribution chamber tangentially, rather than radi ally, or with a combination of tangential and radial vector components. Though not illus trated, it should be understood that multiple inlets 104 can exist in some embodiments, without limitation. FIG. 10 suggests an embodiment wherein fluidizing fluid inlet 104 may enter the fluidization fluid distribution chamber 108 from below, rather than from the side of the main body 103.

A fluidized bed panel 110 extending across the transverse cross-section of the body 103 of the separator 100 may form an upper portion of fluidization fluid distribution chamber 108. The fluidized bed panel 110 may have a number of nozzles 122 provided thereto which enable fluid communication between the fluidization fluid distribution chamber 108 and the main separation chamber 107. As shown, the nozzles 122 may be fitted to existing orifices or openings 111 extending through the fluidized bed panel 110, or, they may be integrated with openings 111 in the fluidized bed panel 110, without limitation. Nozzles 122 may be attached to the panel in any conceivable fashion, and nozzles 122 may be provided within openings 111 prior to securement to the panel 110. Nozzles 122 may be attached to panel 110 to form a sub- assembly, prior to assembling the fluidized bed panel 110 within the separator 100. In some embodiments, the nozzles 122 may only be provided to one side of the fluidized bed panel 110 adjacent each opening 111.

The fluidized bed panel 110 may be flat (e.g., planar) or provided in other preferred ge ometries. For example, in some embodiments (not shown), the fluidized bed panel 110 may be provided in a dished shape (e.g., with concave portion facing upwards into the main separation chamber 107). In some embodiments (as shown in FIG. 2), the fluidized bed panel 110 may be provided in a generally frustoconical shape (e.g., with its center narrowing as it approaches the bottom of the separator 100). At the center of the fluid ized bed panel 110, an orifice or opening may be provided therethrough, and this orifice or opening may fluidly communicate with a central underflow outlet 109 configured for removing underflow 114 (e.g., gangue) from the main separation chamber 107, such that the underflow 114 may be able to find egress out of the central bottom of the separator 100, without limitation. In some embodiments, the fluidized bed panel 110 may be pa raboloidal in shape, without limitation.

The fluidization fluid distribution chamber 108 may further comprise a slipstream outlet 124 and a dissolved air solution inlet 123. In some embodiments of a separator 100, there may be a plurality of one or both of these features 123, 124, without limitation. The slip stream outlet 124 may be configured to receive fluid from the fluidization fluid distribu tion chamber 108 and deliver it to a pump 120, such as a water pump or dissolved air pump, without limitation. The dissolved air solution inlet 123 may be configured to re ceive dissolved air solution from the pump 120 and deliver it to back to the fluidization fluid distribution chamber 108, without limitation. Although a single pump 120 is shown, it is envisaged that multiple pumps 120 may be provided to the separator 100, without limitation. Slipstream fluid 125 leaving the fluidization fluid distribution chamber 108 through the slipstream outlet 124 may be aerated with air 118 (or other gas or gaseous compound) prior to or during entry of the slipstream fluid 125 into the pump 120. For example, air 118 may be introduced via an air inlet 119 as shown in FIG. 2. The air inlet 119 may, in some non-limiting embodiments, be configured as an air sparger, a nozzle, or a valve which is configured to introduce air or gas into the slipstream fluid 125. The air inlet 119 may be specially configured to mix air with the slipstream fluid 125, without limitation. The pump 120 may further entrain air within the slipstream fluid 125 leaving the fluidiza tion fluid distribution chamber 108.

A combination of dissolved air solution 121 leaving the pump 120 and fluidization fluid 112 entering the fluidization fluid distribution chamber 108 may progress through nozzles 122 of the fluidized bed panel 110 and into the main separation chamber 107, thereby forming an evenly-distributed, uniform, layer of bubbles across the fluidized bed panel 110 along the bottom of the main separation chamber 107, due to a prescribed drop in pressure facilitated by the nozzle 122 design. It should be understood that while not shown, some embodiments of the invention may include an air inlet 119 which feeds air into the fluidization fluid inlet 104 so that the fluidization fluid 112 may be pre-aerated with air, without limitation.

Particles in feed slurry 113 may attach to the bubbles exiting nozzles 122 and may rise to an upper separation chamber 106. The upper separation chamber 106 may employ one or more plates, or plate stacks 105, without limitation. A plate stack 105 may be an in clined plate stack, without limitation. As shown, the plate stack 105 may be provided in the upper separation chamber 106 and may comprise a number of diagonally-arranged or inclined plates. The plates in the inclined plate stack 105 may comprise lamella plates, without limitation. The lamellae may be substantially parallel to each other and/or spaced from each other by approximately the same distance, without limitation. Some embodi ments may optionally omit plate stack 105, without limitation. At the top of the upper separation chamber 106 may be provided a weir 116 that allows overflow 115 to pass over it. Overflow 115 may be collected in an overflow outlet 117, for example, a launder which circumferentially surrounds the main body 103, without lim itation. The overflow 115 may be moved to downstream equipment for further pro cessing or holding. Overflow 115 may comprise froth or targeted particles having a par ticular size, density, and/or specific mineralogy, without limitation.

Turning now to the embodiment shown in FIG. 4, a plurality of air inlets 119 may be pro vided to a fluidized bed separator 100 according to the invention. For example, an air inlet 119 may be provided upstream of the pump 120 and/or an air inlet 119 may be provided downstream from the pump 120 for purposes of supplemental aeration of slip stream solution 125. In this regard, dissolved air solution 121 leaving the pump 120 may be twice-aerated with air 118 forming a twice-aerated dissolved air solution 127.

As shown in FIG. 4, an inline mixer or other high shear device 126 may be provided to the dissolved air solution inlet 123 of the fluidized bed separator 100 to further entrain air 118 in the dissolved air solution 121 or twice-aerated dissolved air solution 127 be fore it re-enters the fluidization fluid distribution chamber 108. The inline mixer 126 may, as shown, be positioned between the fluidization fluid distribution chamber 108 and the pump 120, without limitation. The inline mixer 126 may also, as shown, be posi tioned between the fluidization fluid distribution chamber 108 and the secondary air in let 119, without limitation.

Though not shown, a plurality of air inlets 119 may be provided to the slipstream solu tion outlet 124, and/or a plurality of air inlets 119 may be provided to the dissolved air solution inlet 123, without limitation.

Turning now to the embodiment shown in FIG. 5, the air inlet 119 upstream of the pump 120 shown in FIGS. 2 and 4 may be eliminated altogether, wherein a single air inlet 119 may be positioned downstream of the pump 120, and provided to the dissolved air solu tion inlet 123, in order to provide primary air 118 to the slipstream fluid 125, without limitation. In some preferred embodiments, the rate at which slipstream fluid 125 is extracted from the fluidization fluid distribution chamber 108 through the slipstream solution outlet 124 may be independent from (i.e., independently controllable with respect to) the rate at which fluidization fluid 112 is added to or provided to the fluidization fluid distribu tion chamber 108, without limitation. In some preferred embodiments, the slipstream fluid 125 extraction rate may also be controllable and adjustable. Moreover, the rate at which air 118 is added to slipstream solution 125 and/or dissolved air solution 121 is preferably independent from (i.e., separately controllable) the rate at which fluidization fluid 112 is added or introduced. Accordingly, embodiments of a fluidized bed separator 100 may comprise inlets 102, 104, 119, 123 and/or outlets 124 that can be inde pendently adjusted and/or controlled (e.g., using control valves or manual adjustment valves) to suit process needs. In this regard a fluidized bed separator 100 may be ade quately reconfigured as process conditions change and/or as feed slurry 113 properties change over time.

Turning now to FIG. 6, a manifold 140 peripherally encircling or surrounding the body 103 may be provided to a separator 100 according to some embodiments. The manifold 140 may be configured to deliver dissolved air solution 121, 127 to the fluidization fluid distribution chamber 108 in an evenly-distributed manner, via a plurality of entry points 141. In this regard, flow within the fluidization fluid distribution chamber 108 can be made more uniform and without velocity hot spots. It should be understood that the manifold 140 may not necessarily completely encircle or surround the body 103 as illus trated, and that there may fewer or more entry points 141 than what is shown. For ex ample, in some non-limiting embodiments, two diametrically opposed entry points 141 may be employed, wherein the manifold 140 may be "C"-shaped, rather than annular.

As another non-limiting example, three circumferentially-spaced entry points 141 may be provided between manifold 140 and fluidization fluid distribution chamber 108.

More than three circumferentially-spaced entry points 141 may be provided to fluidly connect manifold 140 and fluidization fluid distribution chamber 108 as shown, without limitation. Entry points 141 are preferably equidistantly-spaced, although non-equal spacings are anticipated. Turning now to FIGS. 7 and 8, in some non-limiting embodiments, a separator 100 may comprise an air distribution chamber 128 provided below the fluidization fluid distribu tion chamber 108 as shown. A second fluidized bed panel 110 may separate the two chambers 108, 128, without limitation. The two chambers 108, 128 may fluidly com municate via openings 111 through the second fluidized bed panel 110 - and some or all of these openings 111 may or may not comprise nozzles 122. Air (or gas) 118 may enter the air distribution chamber 128, via an inlet 119. As suggested in FIG. 7, the separator 100 may utilize air 118 entering the air distribution chamber 128 via inlet 119 to aerate fluidization fluid 112 in the fluidization fluid distribution chamber 108. As suggested in FIG. 8, a pump 120 may provide supplemental dissolved air solution 121 to the fluidiza tion fluid distribution chamber 108 in addition to the air (or gas) being introduced via the air distribution chamber 128.

While not shown in FIG. 8, one or more additional air inlets 119 and/or one or more op tional inline mixers or high shear devices (e.g., static mixer) 126 may be provided to dis solved air solution inlet 123 as suggested in FIGS. 5 and 9, without limitation.

As shown in FIG. 9, nozzles 122 of various types may be provided to fluidized bed panel 110, and lower portions of body 103, without limitation. For example, in some embodi ments, one or more nozzles 122 may deliver aerated fluidization fluid 112 from the fluid ization fluid distribution chamber 108 to the main separation chamber 107. In some embodiments, one or more nozzles 122 may provide air (or gas) 118 from outside of the separator 100 to the fluidization fluid distribution chamber 108. In some embodiments, one or more nozzles 122 may provide air (or gas) 118 from outside of the separator 100 directly to the main separation chamber 107. In some embodiments, one or more noz zles 122 may be configured to combine fluidization fluid 112 and/or dissolved air solu tion 121, 127 with air (or gas) 118 from outside of the separator 100, and deliver the same to the main separation chamber 107 (e.g., by virtue of energy transfer between liquid and gas phases), without limitation. Mixing of liquid and gas phases may be facili tated, for example, by operating chambers 128 and 108 (FIGS. 7 and 8) under positive pressures or relative pressure differentials with respect to main separation chamber 107, without limitation. For example, the air distribution chamber 128 may be main tained at a higher pressure than the fluidization fluid distribution chamber 108.

Turning now to FIGS. 11 and 12, by virtue of its configuration, a nozzle 122 described herein may be adapted for mixing fluids including liquid, gas, and combinations thereof (e.g., dissolved air solution 121, 127). For example, a nozzle 122 may comprise features which enable fluids (which may be aerated liquids) within the fluidization fluid distribu tion chamber 108 to combine with air (or gas) 118 entering the separator 100 via the nozzle 122. The separator 100 may comprise pressure differentials between different chambers 107, 108, 128, to assist nozzle 122 function, without limitation.

As shown, such nozzles 122 may be configured with one or more fluid ports 131 for re ceiving fluids (e.g., aerated and/or non-aerated liquids) from the fluidization fluid distri bution chamber 108 so that they may be combined with air (or gas) 118 within the noz zles 122. Nozzles 122 may each comprise means 137 for attaching to the separator 100. For example, a nozzle 122 may be threaded into a component of the separator 100, such as to a fluidized bed panel 110, to a portion of body 103, to an outlet 124, or to an inlet 102, 104, 123, using a torque application surface 136, without limitation. Torque appli cation surfaces 136 may include holes for spanner wrenches, or slots or hex recesses for engaging a hex wrench or screwdriver, without limitation. As suggested in FIG. 13, torque application surfaces 136 may comprise an external nut structure which may be engageable with an open end wrench, box wrench, or socket wrench, without limitation.

As suggested in FIGS. 11 and 12, a nozzle 122 described herein may be a one-piece noz zle design assembled by combining an upper part 129 with a lower part 130. Alterna tively, as suggested in FIG. 13, a nozzle 122 described herein may comprise a two-piece nozzle design, wherein the upper part 129 may be removably or permanently fixed to a component of the separator 100 (such as the fluidized bed panel 110), and the lower part 130 may be removably or permanently fixed to another component of the separa tor 100 (e.g., such as a lower portion of body 103). A nozzle 122 may comprise a single (e.g., annular) fluid port 131 (as suggested in FIG.

13), or, it may have a plurality of fluid ports 131 for receiving fluid containing liquid within the fluidization fluid distribution chamber 108 (as suggested in FIGS. 11 and 12). For example, a fluid port 131 may comprise window-like openings through a portion of the upper part 129, without limitation.

Sealing means 135 may be provided between a nozzle 122 and a component of the sep arator 100, such as the fluidized bed panel 110, as shown in FIG. 11. The upper part 129 of a nozzle 122 may comprise a tube or port 133 for delivering aerated fluid to the main separation chamber 107. The lower part 130 of a nozzle 122 may comprise a tube or port 142 for receiving air (or gas) 118 from a source external to the separator 100. The source of air or gas 118 may be pressurized and/or regulated using control means such as a control valve, without limitation.

The lower part 130 of a nozzle 122 may comprise a tapered outer surface 139, which may comprise a frustoconical or paraboloidic shape, without limitation. The upper part 129 of a nozzle 122 may comprise a corresponding tapered inner surface 134 having a complimentary frustoconical or paraboloidic shape, without limitation. The combined upper 129 and lower 130 parts of the nozzle 122 may collectively form a nozzle struc ture 132. The nozzle structure 132 may be fixed, or, it may be adjustable by controlling the distance between tapered inner 134 and outer 139 surfaces, without limitation. For example, in some embodiments, by engaging torque application surface 136 and rotat ing the lower part 130 a select or predetermined amount (e.g., via threads 137), a sepa ration distance existing between upper 129 and lower 130 parts may be infinitely-ad- justed and controlled thereby affecting nozzle structure 132 and overall performance of nozzle 122.

Nozzles 122 described herein may incorporate features or means 138 for coupling to an air (or gas) 118 source. For example, as shown in FIGS. 11 and 12, a thread (e.g., internal or external NPT thread) for receiving a pneumatic fitting or pipe section may be pro vided to a portion of nozzle (e.g., to the lower part 130 as shown). As another example, a barb or fitting (FIG. 13) configured for receiving an air hose or other air source attach ment may be provided to a portion of the nozzle 122, without limitation.

As shown in the figures, in any proposed embodiment discussed herein, it is envisaged that incoming feed slurry 113 entering the main separation chamber 107 of the separa tor 100 may be optionally pre-contacted with air or gas 118. This may be accomplished in a number of ways.

For example, as suggested in FIGS. 18-24, a number of different technologies may be used to pre-aerate the feed slurry 113, without limitation. Pre-aeration devices may in clude any which are known in the art, including that which is described in Applicant's co pending US provisional application serial no. 62/807,925, which is hereby incorporated herein by reference, in its entirety, for any and all purposes as if fully set forth herein.

For example, in some embodiments, the feed slurry 113 may be entrained with air using cavitation devices (as suggested in FIG. 20) in the feed inlet 102. In some embodiments, the feed slurry 113 may be entrained with air by employing a venturi provided down stream of an air inlet 119 in the feed inlet 102 (as suggested in FIG. 21). In some embod iments, the feed slurry 113 may be entrained with air via an adjustable and/or variable orifice air sparging device provided within the feed inlet 102 (as suggested in FIG. 24). In some embodiments, the feed slurry 113 may be entrained with air using a restricted throat device having a restricted throat section with air introduction means at the throat within the feed inlet 102 (as suggested in FIGS. 18 and 22). In some embodiments, the feed slurry 113 may be entrained with air by virtue of the provision of a high- or low- shear contacting reactor (as suggested in FIG. 19). As suggested in FIG. 23, an air inlet 119 may comprise a nozzle 122 structure or other suitable sparging feature in order to optimize optional pre-contacting of the feed slurry 113 with air or gas 118, prior to entry into the main separation chamber 107, without limitation.

In such described slurry pre-aeration devices, pressurized air 118 may be utilized, and/or these devices may be self-asperating, without limitation. It should be understood that in any of the embodiments, the rate at which air (or gas) 118 is introduced to feed inlet 102 may be independent from (i.e., independently con trollable with respect to) the rate at which feed slurry 113 is introduced to the feed inlet 102, without limitation.

Example

Provide a separator 100 (e.g., an FLSmidth ^® Reflux ^® Classifier) comprising a pressurized fluidization fluid distribution chamber 108. Provide a dissolved air pump 120 and modify the fluidization fluid distribution chamber 108 to accommodate an additional fluidization fluid distribution chamber inlet 123 and a slipstream outlet 124. Convey fluidization fluid 112 to the fluidization fluid distribution chamber 108 via a fluidization fluid inlet 104. Con vey slipstream fluid 125 contents of fluidization fluid distribution chamber 108 to the dis solved air pump 120 via the slipstream outlet 124. Before, adjacent, at, and/or after an interface with the pump 120, provide air 118 to the slipstream fluid 125 leaving the fluid ization fluid distribution chamber 108, such that the slipstream fluid 125 may be aerated.

Optionally, aerate the slipstream fluid 125 twice, for example, aerate the slipstream fluid 125 a first time before it enters the pump 120 and a second time after leaving the pump 120. Convey the dissolved air solution 121 leaving the dissolved air pump 120 (and/or the twice-aerated dissolved air solution 127) back to the fluidization fluid distribution cham ber 108 via the dissolved air solution inlet 123 as shown in FIG. 2. Optionally provide an inline mixer or high shear device 126 to the dissolved air solution inlet 123 upstream of the fluidization fluid distribution chamber 108 for supplemental air entrainment and/or for moderating or homogenizing bubble size distribution.

Further provide suitably designed ejection nozzles 122 to a plurality of openings 111 in the fluidized bed panel 110 so as to generate a homogenous dissolved air solution 121 into the fluidization fluid distribution chamber 108 at a prescribed or required pressure or within a prescribed or required pressure range. Allow an adequate pressure drop to occur across the ejection nozzles 122 between the fluidization fluid distribution chamber 108 and main separation chamber 107, to allow air 118 to come out of solution as fine gas bubbles above the ejection nozzles 122. Configure the nozzles 122 and/or pump 120, along with fluidization fluid 112 feed rate, to ensure that fine gas bubbles leaving the noz zles 122 and entering the main separation chamber 107 are evenly distributed across the full transverse cross-sectional area (e.g., width, diameter, and/or circumference) of the fluidized bed panel 110 and/or of the body 103 of the separator 100. Maintain an ade quate fluidized bed within the main separation chamber 107.

Optionally pre-aerate the feed slurry 113 by combining it with air or gas 118 in the feed inlet 102.

Where it is used herein in the description and in the appending claims, the word "air" may be substituted in its entirety with the word "gas", and vice versa. Accordingly, where used herein, the term "air" can be interchanged with the broader word "gas". Those features (e.g., "air distribution chamber 128") which contain the word "air" may be broadly interpreted as if the term "air" is substituted with the term "gas" (e.g., a "gas distribution chamber" 128), without limitation. The term "air" where used herein and in the claims, may comprise any gas or gas mixture, including gaseous mixtures with air, and may include pure gaseous fluids such as carbon dioxide, nitrogen, or the like, with out limitation. Accordingly, while the word "air" is used ubiquitously and consistently throughout this description and claims, the inventors anticipate that gaseous com pounds (other than air) may be equally employed without departing from the spirit and scope of the invention.

Moreover, where it is used herein in the description and in the appending claims, the term "dissolved air solution" or "dissolved gas solution" 121, 127 may broadly comprise liquids having dissolved air or gas therein and may also comprise liquids having air or gas bubbles entrained therein, without limitation. Accordingly, the term "dissolved air solu tion" or "dissolved gas solution" 121, 127 should be interpreted as inclusive of bubbly fluids, and liquid-gas mixtures, without limitation.

In embodiments where two air inlets 119 might be employed to the fluidized bed sepa rator 100, different amounts or flow rates of air 118 may be provided to each air inlet 119. Different types of gas may be provided to each air inlet 119. Moreover, each air inlet 119 may comprise different geometries - e.g., one air inlet 119 may comprise a valve and another air inlet 119 may comprise a sparger, without limitation.

It should be known that the specific features, function, process steps, and possible bene fits shown and described herein in detail are purely exemplary in nature and should not limit the spirit and/or scope of the invention.

Moreover, although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of these teachings, can generate additional embodiments and modifications without departing from the spirit of the claimed invention. For example, while the inline mixer 126 is shown being provided to the dissolved air solution inlet 123, it should be understood that an inline mixer 126 could al ternatively, or in combination, be provided to the slipstream solution outlet 124, without limitation.

Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be con strued to limit the scope thereof.

Listing of Reference Numerals

1 - Prior art separator

2 - Feed inlet

3 - Main body

4 - Fluidizing fluid inlet

5 - Inclined (lamellae) plate stack

6 - Upper separation chamber

7 - Main separation chamber

8 - Fluidized bed chamber

9 - Underflow outlet

10 - Fluidized bed panel

11 - Opening (through fluidized bed panel)

12 - Fluidizing fluid

13 - Feed slurry

14 - Underflow (e.g., gangue)

15 - Overflow (e.g., froth)

16 - Weir

17 - Launder

100 - Separator according to preferred embodiments of the invention

102 - Feed inlet

103 - Main body

104 - Fluidizing fluid inlet

105 - Inclined (lamellae) plate stack

106 - Upper separation chamber

107 - Main separation chamber

108 - Fluidization fluid distribution chamber

109 - Underflow outlet

110 - Fluidized bed panel

111 - Opening (through fluidized bed panel)

112 - Fluidizing fluid (e.g., water)

113 - Feed slurry (e.g., crushed ore, process water, reagent) 114 - Underflow (e.g., gangue)

115 - Overflow (e.g., froth, selected mineral value)

116 - Weir

117 - Overflow outlet (e.g., launder)

118 - Air (or other gas)

119 - Air (gas) inlet

120 - Pump

121 - Dissolved air solution

122 - Nozzle

123 - Dissolved air solution inlet

124 - Slipstream outlet

125 - Slipstream fluid

126 - Inline mixer or high shear device (e.g., static mixer)

127 - Twice-aerated dissolved air solution

128 - Air (gas) distribution chamber

129 - Upper part

130 - Lower part

131 - Fluid port

132 - Nozzle structure

133 - Tube or port

134 - Tapered inner surface (e.g., frustoconical, paraboloidic)

135 - Sealing means

136 - Torque application surface or means for applying torque (e.g., hex recess or nut surface)

137 - Nozzle attachment means (e.g., external thread)

138 - Air coupling attachment means (e.g., internal thread for receiving air coupling)

139 - Tapered outer surface (e.g., frustoconical, paraboloidic)

140 - Manifold (e.g., with multiple peripheral entry points to fluidization fluid distribution chamber 108)

141 - Multiple entry points

142 - Tube or port (for conveying air or gas)