EA045242B1 - FLOTATION DEVICE AND FLOTATION METHOD - Google Patents

Description

State of the art

The invention relates to a flotation device. The invention also relates to a flotation method.

There is a need to improve the efficiency of flotation in processes for liberating valuable minerals from mineral ores.

The essence of the invention

From the point of view of the first aspect, a flotation device may be provided comprising a mill configured to produce pulp, a flotation section comprising at least one flotation unit with a feed system for receiving the pulp to be processed in said flotation unit, an overflow means for removing flotation concentrate, outlet for removing the underproduct. The flotation unit contains a fluidized bed device containing devices for creating a fluidized layer, and/or a foam device containing devices for creating a foam layer, wherein to interact with the foam layer, particles are fed into the foam layer, under the foam layer in the immediate vicinity thereof, or over a foam layer, or any combination. The flotation section is followed by a first classifier, and the flotation section (12) is configured to receive pulp feed from the mill, from which particles smaller than 300 microns have not been removed. The flotation section is operatively coupled to the inlet of the first classifier to separate said underflow leaving the flotation section into a fine underflow stream (F) and a coarse underflow stream representing tailings.

Thus, the flotation device provides a wide particle size distribution, containing both smaller and larger particles. Surprisingly, it has been discovered that very efficient flotation of larger particles containing valuable minerals is achieved by combining said larger particles with smaller particles. However, some of the smaller particles containing valuable minerals enter the flotation underflow, from where they are recovered in the first classifier. In addition, the device allows you to improve the grade of small particles.

In terms of the second aspect, a flotation method may be provided comprising supplying a pulp feed to a mill, supplying from the mill a feed from which particles smaller than 300 µm have not been removed, to a flotation section comprising at least one flotation unit, wherein the flotation unit ( 1) contains a device with a fluidized bed, containing devices for creating a fluidized layer and/or a foam device containing devices for creating a foam layer, and in order to interact with the foam layer, particles are fed into the foam layer, under the foam layer in the immediate vicinity of it or above it froth bed, or in any combination, removing the flotation concentrate as an overflow from the flotation section, removing the underflow from the flotation section, feeding the underflow to a first classifier, and separating the underflow into a fine underflow stream and a coarse underflow stream in the first classifier.

Thus, a flotation process with a wide particle size distribution is provided, containing both smaller and larger particles. Surprisingly, it has been discovered that very efficient flotation of larger particles containing valuable minerals is achieved by combining said larger particles with smaller particles. However, some of the smaller particles containing valuable minerals enter the underproduct of the flotation process, from where these particles are recovered in the first classifier. In addition, the method allows you to increase the grade of small particles.

The device and method are characterized by what is stated in the independent claims of the invention. Some other embodiments are characterized by what is stated in other claims. Embodiments in accordance with the invention are also disclosed in the description and drawings of the present patent application. The content of the patent application according to the invention may also be defined differently from that defined in the following claims. The content according to the invention may also be formed from several separate inventions, especially if the invention is considered in the light of expressed or implied subobjects or in view of the advantages or groups of advantages obtained. Some of the definitions contained in the following claims may be unnecessary in view of certain teachings of the invention. Features of various embodiments of the invention may, within the scope of the main idea of the invention, be applicable to other embodiments.

In one embodiment, the flotation unit includes devices for creating a fluidized bed. The advantage is that the valuable particles float and at least most of the fine particles are recovered. This allows for immediate disposal of coarse tailings. Another advantage is that fine particles can be processed downstream in standard flotation equipment with higher separation efficiency.

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In one embodiment, the flotation unit includes devices for creating a froth layer, wherein to interact with the froth layer, particles are fed into the froth layer, under the froth layer in close proximity thereto, or above the froth layer, or any combination. The advantage is that the size of the flotation unit can be reduced, high throughput per unit flotation volume can be achieved, and direct interaction with the foam/bubbles results in potentially higher recoveries.

In one embodiment, the flotation unit includes devices for creating a fluidized bed and devices for creating a foam layer, wherein to interact with the foam layer, particles are fed into the foam layer, under the foam layer in close proximity thereto, or above the foam layer, or in any combination . The advantage is that the recovery of large valuable minerals into the concentrate can be maximized.

In one embodiment, the classifier comprises a classifier cyclone. The advantage is that a simple design without moving parts can be achieved.

In one embodiment, the fine underflow stream from the first classifier is provided to be supplied to a flotation system comprising at least one flotation cell. The advantage is that valuable minerals can be extracted.

In one embodiment, the flotation cell is a fluidized bed device comprising devices for creating a fluidized bed. The advantage is that recovery of near-floating particles can be improved by adding additional buoyancy to the fluidized bed.

In one embodiment, the flotation cell is a device containing devices for creating a foam layer, wherein to interact with the foam layer, particles are introduced into the foam layer, under the foam layer in close proximity thereto, or above the foam layer, or in any combination. The advantage is that particle recovery can be improved by direct addition to the foam layer.

In one embodiment, the flotation system includes at least three flotation cells arranged in series such that the underflow outlet of the preceding flotation cell is connected to the inlet of the subsequent flotation cell. The advantage of this is that valuable minerals can be extracted from the bottom product.

In one embodiment, the flotation cell includes a device comprising an inlet connected to receive feed to be processed in said flotation cell and located at the bottom of the flotation cell, an overflow means for removing flotation concentrate located at the top of the flotation cell, and an outlet for removing underflow, located at the bottom of the flotation chamber. The advantage is that due to the high energy input and good mixing properties, high recoveries can be achieved.

In one embodiment, the flotation cell includes a mechanical stirrer for mixing the pulp in the cell. The advantage is that the separation of particles containing valuable minerals from other particles can be enhanced.

In one embodiment, the flotation cell includes a mechanical stirrer to create bubbles in the cell. The advantage is that the separation of particles containing valuable minerals from other particles can be enhanced.

In one embodiment, the flotation cell is a closed pressurized flotation cell wherein flotation concentrate is removed from the cell under pressure. The advantage is that high recovery can be achieved since there is no foam loss.

In one embodiment, the flotation cell contains devices for pneumatic gas supply. The advantage is that higher product grade and/or improved fines recovery can be achieved.

In one embodiment, at least one of the flotation cells is a device for separating foam, containing devices for creating a layer of foam, containing an inlet connected to receive feed to be processed in the specified flotation cell, and located in the upper part of the flotation vessel, an overflow a means for removing flotation concentrate located at the top of the flotation cell; and an outlet for removing underflow located at the bottom of the flotation cell. The advantage is that a high grade of product can be achieved.

In one embodiment, the flotation cell includes a standpipe for feeding the slurry, the standpipe having a nozzle for supplying pressurized flotation gas to the slurry. The advantage is that high recovery can be achieved as a result of localized high energy input. Another advantage is that the re-extraction of fine particles can be improved.

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In one embodiment, the standpipe includes an outlet nozzle configured to create a supersonic shock wave in the slurry as it exits the standpipe. The advantage is that the flotation of fine and ultra-fine particles containing, for example, mineral ore or coal can be improved.

In one embodiment, the device includes a second separator configured to prevent large particles from entering the first classifier. The advantage is that particles that contain valuable minerals but are too large to be released into the fine underflow can be recovered.

In one embodiment, a second separator is located upstream of the flotation unit to prevent large particles from entering the flotation unit and the first classifier. The advantage is that it is possible to avoid introducing particles into the flotation unit that contain valuable minerals but are too large to enter the fine underflow stream.

In one embodiment, the second separator is located between the flotation unit and the first classifier. The advantage is that particles that contain valuable minerals but are too large to enter the fine underflow can be recovered.

In one embodiment, the second separator includes a grate or grate. The advantage is that a simple separator design can be achieved.

In one embodiment, a second classifier is connected to the mill to return large particles back to the mill for further grinding. The advantage is that large particles containing valuable minerals can be crushed to a size that can be released into the fine underflow stream.

In one embodiment, the flotation unit is located in an open loop configuration. The advantage is that the simple configuration reduces energy consumption and reduces capital and operating costs.

In one embodiment, the flotation unit is located in a closed loop configuration. The advantage is that particle recycling can increase the recovery of valuable minerals.

Brief description of drawings

Certain embodiments illustrating the present invention are shown in more detail in the accompanying drawings, in which

Fig. 1 schematically illustrates the device and method.

Fig. 2 schematically illustrates another apparatus and method.

Fig. 3 schematically illustrates the flotation system and method.

Fig. 4 schematically illustrates another flotation system and method.

Fig. 5 schematically illustrates a third flotation system.

In the drawings, some embodiments are shown in a simplified manner for the sake of clarity. Similar parts are designated in the drawings by the same reference numbers.

Detailed description

Fig. 1 schematically illustrates a flotation device 100 and method.

The device 100 includes a mill 2 configured to produce pulp, and a flotation section 12 containing at least one flotation unit 1.

The mill 2 may be, for example, an autogenous mill or a semi-autogenous mill, or a high pressure mill.

In the embodiment shown in FIG. 1, the flotation section 12 contains one flotation unit 1. In other embodiments, the flotation section may have two, three or even more flotation units. If there are several flotation units, they may all be of the same type or, alternatively, at least two types of flotation units may be provided.

Flotation unit 1 contains a feed system 3 configured to receive pulp to be processed in said flotation unit 1, from which pulp particles smaller than 300 μm have not been removed. The location of the feed system 3 depends on the type of flotation unit 1. Thus, the feed system 3 can be located in the lower part, in the upper part or in the middle part of the flotation unit 1.

Flotation unit 1 further comprises an overflow means 4 for removing flotation concentrate from said flotation unit and an outlet 5 for removing underflow from said flotation unit.

In embodiments containing multiple flotation units, these units are arranged in series such that the first of the flotation units 1 is configured to receive pulp to be processed in the flotation section 12, and the outlet 5 of the preceding flotation unit 1 is connected to the feed system 3 of the subsequent flotation unit. 1. The last of said plurality of flotation units 1 is configured to remove the underflow from the flotation section 12.

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The device 100 further includes a first classifier 6 comprising an inlet 7. The inlet 7 is configured to receive underflow from the flotation section 12. The first classifier 6 is configured to separate the underflow into a fine underflow stream F and a coarse underflow stream consisting of tailings.

In one embodiment, the flotation unit 1 includes a fluidized bed device having devices for creating a fluidized bed in the flotation unit 1. In another embodiment, the flotation unit 1 includes a froth device having devices for creating a froth layer in the flotation unit 1. The froth layer can interact with particles of the product flow. In one embodiment, the product flow is arranged such that it is supplied into the foam layer, under the foam layer in close proximity thereto, or above the foam layer, or any combination. The term "close proximity" as used herein means a distance of 20 cm or less from the foam layer.

In one embodiment, the product flow is directed into the foam layer, under the foam layer at a distance of no more than 2 cm from it, or above the foam layer, or any combination.

In one embodiment, the flotation unit 1 contains both devices for creating a fluidized bed and devices for creating a foam layer.

In one embodiment, the first classifier 6 includes a cyclone. In other embodiments, the first classifier 6 contains, in addition to or as an alternative to the cyclone, one or more non-mechanical sedimentation classifiers, for example, a settling cone; a mechanical sedimentation classifier, such as a rake classifier or a spiral classifier; stepless classifier; and a difficult-to-settle classifier, such as a hydraulic valve.

In one embodiment, a fines underflow stream F is supplied from the first classifier 6 to a flotation system 20 comprising at least one flotation cell 21. The flotation system 20 is discussed in more detail with reference to FIG. 3 and 4.

Fig. 2 schematically illustrates another apparatus and method.

In one embodiment, the device includes a second separator 13 that is configured to prevent large particles from entering the first classifier 6. The large particles may contain valuable minerals, but they are too large to enter the fine underflow stream F.

In one embodiment, such as shown in FIG. 2, the second separator 13 is located between the flotation chamber 1 and the first classifier 6. In another embodiment, the second separator 13 is located in front of the flotation chamber 1 to prevent large particles from also entering the flotation unit 1.

In one embodiment, the second classifier 13 includes a grate or grate.

In one embodiment, such as shown in FIG. 2, the second classifier 13 is connected to the mill 2 so that large particles can be returned to the mill 2 for further grinding.

Fig. 3 schematically illustrates a flotation system and method, and FIG. 4 schematically illustrates another flotation system and method. The flotation system 20 is configured to be in fluid communication with the first classifier 6 described herein such that the fines stream F created in the first classifier 6 is supplied to the flotation system 20, which includes at least one flotation cell 21.

In one embodiment, the first classifier 6 operates in an open loop configuration, that is, without recycling material back to the first classifier 6.

In one embodiment, the flotation cell 21 is one of the following: a fluidized bed device containing devices for creating a fluidized bed, or a device containing devices for creating a foam layer, and to interact with the foam layer, particles are fed into the foam layer, under the foam layer in the immediate vicinity thereof, or above the froth bed, or any combination thereof, or a device containing devices for pneumatic gas supply, or a closed pressurized flotation cell, the flotation concentrate being removed from the cell under pressure, or a device (such as shown in Fig. 3), comprising an inlet 22 connected to receive feed to be processed in said flotation cell, and located at the bottom of the flotation cell 21, an overflow means 15 for removing flotation concentrate located at the top of the flotation cell (21) , and an underflow outlet 25 located at the bottom of the flotation cell 21. The term close proximity as used herein means a distance of 20 cm or less from the froth layer.

In one embodiment, the flotation system 20 includes at least three flotation cells 21 arranged in series such that the underflow outlet 25 of the preceding flotation cell 21 is connected to the inlet of the subsequent flotation cell 21. In one embodiment, All flotation cells 21 in the flotation unit 20 are of the same type. In another embodiment, the flotation unit 20 has at least two types of flotation cells 21.

In one embodiment, the flotation cell 21 includes a mechanical stirrer for mixing the pulp in the said cell. Additionally or alternatively, a mechanical stirrer can be used to create bubbles in the chamber.

In one embodiment (eg, shown in FIG. 4), the flotation cell 21 is a froth separating device comprising devices for creating a foam layer, wherein an inlet 22 connected to receive feed to be processed in said flotation cell is located in the top of the flotation cell 21, an overflow means 15 for removing flotation concentrate is located at the top of the flotation cell 21, and an outlet 19 for removing underflow is located at the bottom of the flotation cell 21.

In one embodiment, the flotation cell 21 includes at least one standpipe that feeds slurry into the cell. The downpipe has a nozzle for supplying flotation gas under pressure into the pulp. In addition, the standpipe includes an outlet nozzle that is configured to induce a supersonic shock wave in the gas-slurry mixture as it exits the standpipe.

Fig. 5 schematically illustrates a third flotation system. As has already been described, in one embodiment, the flotation cell 21 is a closed pressurized cell in which pressure flotation can take place and from which the flotation concentrate is removed under pressure. In one embodiment, no foam is formed in the chamber, but loaded bubbles are collected before foam is formed.

An inlet 22 may be located at the bottom of the flotation cell 21, an overflow 15 may be located to discharge flotation concentrate at the top of the flotation cell 21, and an underflow outlet 19 may be located at the bottom of the flotation cell 21. Flotation Cells 21 can be installed at the same level (as shown), since the flow from one chamber to the next occurs due to the pressure created in the chamber.

In one embodiment, the underflow outlet 19 may be located at the top of the flotation cell 21.

In one embodiment, the pressure chamber includes a mechanical stirrer. One example of this type of chamber is known as a Direct Flotation Reactor (DFR).

It should be noted here that all flotation cells 21 located in the flotation system 20 may be of one type or, alternatively, may be at least two types of flotation cells.

The invention is not limited to only the embodiments described above, but instead many embodiments are possible within the scope of the inventive concept defined by the following claims. Within the scope of the inventive concept, features of various embodiments and applications can be used in combination with or replace features of another embodiment or application.

The drawings and related description are provided solely to illustrate the idea of the invention. The invention may vary in detail within the scope of the inventive idea as defined in the following claims.

Item numbers:

- flotation unit;

- mill;

- feeding system;

- overflow agent;

- outlet;

- classifier;

- classifier inlet;

- flotation section;

- second separator;

- overflow agent;

- flotation system;

- flotation chamber;

- flotation chamber inlet;

- outlet for the lower product;

100 - device;

F - flow of fine underproduct.

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Claims (27)

CLAIM 1. Flotation device (100) containing a mill (2) configured to produce pulp, a flotation section (12) containing at least one flotation unit (1) having: a supply system (3) for receiving pulp intended for processing in said flotation unit (1), an overflow means (4) for removing the flotation concentrate, an outlet (5) for removing the underproduct, wherein the flotation unit (1) contains a device with a fluidized bed containing devices for creating a fluidized layer, and/or a foam device containing devices for creating a foam layer, and to interact with the foam layer, particles are fed into the foam layer, under the foam layer in close proximity thereto, or above the foam layer, or in any combination, and behind the flotation section (12) there is a first classifier (6), while the flotation section (12) also contains a separator (13), designed to prevent large particles from entering the first classifier (6), and is configured to receiving pulp feed from the mill (2), from which particles smaller than 300 microns have not been removed, while the flotation section (12) is functionally connected to the inlet (7) of the first classifier to separate the underproduct leaving the flotation section (12) into a fine underflow stream (F) and a coarse underflow stream representing tailings. 2. Device according to claim 1, in which the flotation unit (1) contains said devices for creating a fluidized bed. 3. The device according to claim 1, in which the flotation unit (1) contains the specified devices for creating a foam layer, wherein to interact with the foam layer, particles are fed into the foam layer, under the foam layer in the immediate vicinity of it or above the foam layer, or in any combination. 4. The device according to claim 1, in which the flotation unit (1) contains the specified devices for creating a fluidized layer and the specified devices for creating a foam layer, while in order to interact with the foam layer, particles are fed into the foam layer, under the foam layer in the immediate vicinity of it, or above the first layer, or in any combination. 5. Device according to any of the preceding claims, wherein the first classifier (6) is a cyclone. 6. Apparatus as claimed in any one of the preceding claims, wherein the fine underflow stream (F) from the first classifier (6) is provided to be supplied to a flotation system (20) comprising at least one flotation cell (21). 7. The device according to claim 6, in which the flotation cell (21) is a fluidized bed device containing devices for creating a fluidized bed, or a device containing devices for creating a foam layer, and to interact with the foam layer, particles are fed into the foam layer , under the foam layer in close proximity thereto, or above the foam layer, or in any combination, or a device containing devices for pneumatic gas supply, or a device containing a closed chamber for flotation under pressure, the flotation concentrate being removed from the chamber under pressure, or a device comprising an inlet (22) connected to receive power to be processed in said flotation cell, and located at the bottom of the flotation cell (21), an overflow means (15) for removing flotation concentrate located at the top of the flotation cell ( 21), and an outlet (25) for removing underflow, located at the bottom of the flotation cell (21). 8. Device according to claim 7, in which the flotation chamber (21) is: a device comprising devices for pneumatically supplying gas, or a device containing a closed chamber for flotation under pressure, wherein flotation concentrate is removed from the chamber under pressure, or a device comprising an inlet (22) connected to receive power to be processed in said flotation cell , and located at the bottom of the flotation cell (21), an overflow means (15) for removing flotation concentrate located at the top of the flotation cell (21), and - 6 045242 outlet (25) for removing underflow, located at the bottom of the flotation chamber (21). 9. Device according to claim 8, in which the flotation chamber (21) is: a device comprising a closed pressurized flotation chamber, wherein flotation concentrate is removed from the chamber under pressure, or a device comprising an inlet (22) connected to receive power to be processed in said flotation chamber and located at the bottom of the flotation chamber (21 ), an overflow means (15) for removing flotation concentrate located at the top of the flotation cell (21), and an outlet (25) for removing underflow located at the bottom of the flotation cell (21). 10. Apparatus according to claim 9, wherein the flotation system (20) comprises at least three flotation cells (21) arranged in series such that the underflow outlet (25) of the preceding flotation cell (21) is connected to the inlet hole (22) of the subsequent flotation chamber (21). 11. The device according to claim 9, in which the flotation chamber (21) contains a device containing: an inlet (22) connected to receive feed to be processed in said flotation cell and located at the bottom of the flotation cell (21), an overflow means (15) for removing flotation concentrate located at the top of the flotation cell (21), and an outlet (25) for removing underflow, located at the bottom of the flotation cell (21). 12. Device according to claim 11, in which the flotation chamber (21) contains devices for creating a foam layer. 13. Apparatus according to claim 9, wherein the flotation cell (21) comprises a closed pressurized flotation chamber, wherein the flotation concentrate is removed from the chamber under pressure. 14. Device according to any one of claims 11 to 13, in which the flotation chamber (21) contains a mechanical stirrer for mixing the pulp in said chamber. 15. Apparatus according to any one of claims 11 to 14, wherein the flotation chamber (21) contains a mechanical stirrer for creating bubbles in said chamber. 16. The device according to claim 7, in which the flotation chamber (21) contains devices for pneumatic gas supply. 17. The apparatus of claim 16, wherein the flotation cell (21) is a foam separating device comprising devices for creating a foam layer, comprising an inlet (22) connected to receive feed to be processed in said flotation cell, and located at the top of the flotation cell (21), and an overflow means (15) for removing flotation concentrate located at the top of the flotation cell (21). 18. Apparatus according to claim 16 or 17, wherein the flotation cell (21) includes an underflow outlet (19) located at the bottom of the flotation cell (21). 19. The apparatus of claim 17, wherein the flotation chamber (21) includes a downpipe for supplying slurry, the downpipe having a nozzle for supplying pressurized flotation gas into the slurry. 20. The apparatus of claim 19, wherein the downcomer includes an outlet nozzle configured to excite a supersonic shock wave in the slurry as it exits the downcomer. 21. Device according to any one of claims 1 to 20, in which the separator (13) is located in front of the flotation unit (1) and is designed to prevent large particles from entering the specified flotation unit (1) and the first classifier (6). 22. Device according to any one of claims 1 to 20, in which the separator (13) is located between the flotation chamber (1) and the first classifier (6). 23. Device according to any of the preceding paragraphs, in which the separator (13) contains a grate or grate. 24. Apparatus as claimed in any one of the preceding claims, wherein a separator (13) is connected to a mill (2) to return large particles back to the mill (2) for further grinding. 25. An apparatus as claimed in any one of the preceding claims, wherein the flotation cell (1) is arranged in an open circuit configuration. 26. Apparatus according to any one of claims 1 to 24, wherein the flotation chamber (1) is arranged in a closed loop configuration. 27. A flotation method, including creating a power supply to the mill (2), supplying power from which particles smaller than 300 microns have not been removed from the mill (2) to a flotation section (12) containing a separator (13) configured to prevent butt -