WO2011128154A1

WO2011128154A1 - Gassing device for a flotation cell

Info

Publication number: WO2011128154A1
Application number: PCT/EP2011/053264
Authority: WO
Inventors: Stefan Blendinger; Robert Fleck; Gerold Franke; Lilla Grossmann; Werner Hartmann; Wolfgang Krieglstein
Original assignee: Siemens Aktiengesellschaft
Priority date: 2010-04-12
Filing date: 2011-03-04
Publication date: 2011-10-20
Also published as: EP2377620A1

Abstract

The invention relates to a gassing device (1, 1', 1'', 1''') for a flotation cell (100), comprising a vessel (2) having at least one gas inlet opening (2a) and a number of gas outlet openings (2b) for a gas (7), and a baffle plate (4), which is associated with the vessel (2) and is arranged in such a way that the gas (7), after leaving the vessel, strikes the baffle plate (4), and further comprising at least one gas-permeable, screen-like or lattice-like component (5, 5', 5a, 5b) arranged parallel to the plane of the baffle plate (4) between the gas outlet openings (2) and the baffle plate (4), wherein the screen-like or lattice-like component (5, 5', 5a, 5b) comprises at least one screen element in the form of a mesh, woven or knitted fabric. The invention further relates to a flotation cell (100) having such a gassing device (1, 1', 1'', 1''') and to a flotation process.

Description

description

BEGINNING DEVICE FOR A FLOTATION CELL

The invention relates to a gassing device for a flotation cell, one with at least one such

Fumigation equipped flotation cell, as well as a method for flotation of recyclable particles from a suspension.

Flotation is a physical separation process for

Separation of fine-grained solid mixtures, such as ores and gangue, in an aqueous suspension or suspension with the aid of air bubbles due to a

different surface wettability in the

Suspension contained particles. It is used for the treatment of mineral resources and in the processing of preferably mineral substances with a low to medium

Content of a useful component or a valuable substance

used, for example in the form of non-ferrous metals, iron, metals of the rare earths and / or precious metals and non-metallic mineral resources. WO 2006/069995 Al describes a pneumatic

Flotation cell with a housing comprising a flotation chamber, with at least one nozzle arrangement, here as

Ejectors, further with at least one

Fumigation device when using air

Called aeration devices or aerators, as well as a collecting container for a formed during the flotation

Foam product.

In the pneumatic flotation is generally a with

Reagents mixed suspension of water and fine-grained solid via at least one nozzle assembly in a

Flotationskammer introduced. The reagents should cause, in particular, the valuable, preferably to be separated Particles or recyclable particles are formed hydrophobic in the suspension. In most cases, xanthates are used as reagents, in particular to hydrophobize sulfidic ore particles selectively. At the same time as the suspension, at least one nozzle arrangement is supplied with gas, in particular air, which is mixed with the hydrophobic particles in the air

Suspension comes into contact. The hydrophobic particles adhere to forming gas bubbles, so that the

Gas bubble structures, also called aeroflakes, float and form the foam product on the surface of the suspension. The foam product is discharged into a collecting container and usually thickened.

The quality of the foam product or the separation success of the process of flotation is among others of the

Collision probability between a hydrophobic

Particles and a gas bubbles dependent. The higher the

Collision probability, the greater the number of hydrophobic particles that adhere to a gas bubbles, rise to the surface and together with the particles form the foam product.

A preferred diameter of the gas bubbles is less than about 5 mm and is in particular in the range between 1 and 5 mm. Such small gas bubbles have a high

specific surface and are therefore able to bind significantly more valuable material particles, in particular ore particles, per amount of gas used and take with it, as it are larger gas bubbles in the situation.

In general, gas bubbles of larger diameter increase

faster than gas bubbles of smaller diameter. The smaller gas bubbles are collected by larger gas bubbles and combine with them to even larger gas bubbles. This reduces the available specific surface of the gas bubbles in the suspension, can be bound to the valuable particles. In the case of columnar flotation cells, in which a diameter of the flotation chamber is many times smaller than its height, the path is one

Gas bubbles must travel in the suspension or the flotation to get to the surface of the suspension, particularly large. Due to the particularly long way, particularly large gas bubbles are formed in the suspension.

As a result, the specific discharge of recyclable particles from the suspension and thus also the efficiency of the

Flotation cell.

In so-called hybrid flotation cells, which represent a combination of a pneumatic flotation cell with a columnar flotation cell, larger particulate matter having particle diameters in the range of 50 .mu.m and larger are not completely bound to the gas bubbles present and thus can only be partially separated from the suspension. Fines with

Particle diameters in the range of 20 ym and less, however, are particularly well deposited.

Gas bubbles having a diameter in the range from 1 to 5 mm are continuously present in a column-like flotation cell over the height of the flotation chamber, a reduction of the diameter in the lower region of the flotation chamber or by a

Fumigation device in the flotation chamber generated gas bubbles required. So far, in the flotation gassing with gas outlet openings are used, whose diameter is in the range of 3 to 5 mm and in columnar flotation cells to a

Gas bubble formation with significantly too large gas bubbles,

especially greater than 5 mm in diameter, lead. Another reduction in the diameter of the

Gas outlet openings of gassing is hardly possible in practice. For example, gas outlet openings with diameters of up to 1 mm clog gassing facilities easy, provided that usually to be processed suspensions are used with solids contents in the range of 30 to 40%. Even with short downtimes of

Flotation cell penetrate particles from the suspension into the gas outlet openings and close them. When restarting the cell, the gas pressure of the gas to be introduced into the suspension is often insufficient to flush such small gas outlet openings of a gassing device freely again.

US 2008/0001312 AI describes a device for

Production of microbubbles less than 100 ym in one

Liquid. The device comprises a horizontal

Baffle plate with a series of openings through which the gas bubbles flow and are further divided.

US 4,287,054 A describes a hydraulic-pneumatic flotation device for the separation of minerals in a suspension. In the flotation cell plates are provided with openings through which the suspension is supplied with air permeated water. The plates are not used here to control the size of the air bubbles.

US 4,152,409 A describes a method for carrying out an oxidation process by means of air and adding fine air bubbles to a liquid. The air is injected into the liquid by means of a nozzle and the mixture of air and liquid is forced through openings in a plate.

US 4,374,030 A discloses a method and a

Apparatus for separating a finely divided phase from a continuous phase by means of counter-rotating turbines. It is an object of the invention to provide an improved

To provide a gassing device which is able to produce gas bubbles with a particularly small diameter, and further a flotation cell with such a Gassing device and specify a method for their operation.

The object is achieved by a gassing device for a flotation cell, comprising a vessel with at least one gas inlet opening and a number

Gas outlet openings for a gas, as well as a, the vessel downstream impact plate, which is arranged such that the gas bounces after leaving the vessel against the baffle plate, and at least one between the

Gas outlet openings and the baffle plate parallel to

Plate-level of the baffle plate arranged, gas-permeable screen or lattice-shaped component, wherein the screen or lattice-shaped member comprises at least one screen element in the form of a braid, fabric, knitted fabric or knitted fabric.

The screen or lattice-shaped component is arranged in the transport direction of the gas bubbles generated at the gas outlet openings. The gas bubbles pass the sieve or

grid-shaped component, wherein the gas bubbles are divided. As a result, the diameter of the gas bubbles, regardless of the diameter of the gas outlet openings, reduced. The

Diameter of the gas outlet openings of the gassing device according to the invention can therefore be chosen so large that a clogging by particles from the suspension is always reliably avoided, for example in the range of at least 3 mm, in particular in the range of 3 to 5mm. Depending on which sieve-like or grid-shaped component or which mesh size is selected for the component, are in the suspension over the entire height of the flotation chamber

Only gas bubbles with a diameter in the range of 1 to 5 mm available, which allow optimal separation of the valuable particles and a high yield. According to the invention, the sieve-like or lattice-shaped component comprises at least one sieve element in the form of a mesh, fabric, knitted fabric or knitted fabric in order to cut the gas bubbles particularly finely. In particular, to form the mesh, Woven, knitted or knitted metal wires and / or

Plastic fibers with diameters up to 1 mm are used to form the sharpest and thus most effective separating edge for the impinging gas bubbles.

The baffle plate of the at least one gassing device is preferably above the vessel of the at least one in the flotation chamber of the flotation cell

Gassing arranged. The Andes

Gas bubbles formed gas outlet openings move due to the buoyancy in a suspension up in

Direction baffle plate.

In particular, a center of the baffle plate and a center of the at least one screen or lattice-shaped component are arranged on a longitudinal axis LA of the vessel.

In a preferred embodiment of the invention, the gassing device has a tube section adjoining the vessel for receiving gas exiting via the gas outlet openings, wherein the baffle plate is assigned to an end of the tube section facing away from the vessel and its plate plane is perpendicular to a tube longitudinal axis of the tube

Pipe section is aligned, wherein a center of the baffle plate and a center of the at least one screen or lattice-shaped component lie on the tube longitudinal axis. In a flotation cell, the suspension penetrates into the

Pipe section of the gassing on and off the

Gas outlet openings escaping gas is mixed in the pipe section with the suspension.

It has proven useful if the gassing device has at least two screen or lattice-shaped components. These are preferably connected in series such that the gas bubbles successively all existing sieve or lattice-shaped

Have to pass components and at least part of each of the components are divided into smaller gas bubbles. It is advantageous if with increasing distance of a sieve or lattice-shaped component of the

Gas outlet openings the mesh sizes of the components

lose weight . Furthermore, it is advantageous if viewed in the direction of ascent of the gas bubbles, the meshes of the at least two screen or lattice-shaped component not arranged congruent to each other, but rather offset or rotated

are arranged to each other. This will be the

Probability that a gas bubbles already divided at a first screen or lattice-shaped component is divided a further time at a subsequent screen or lattice-shaped component, significantly increased. In this case, a screen or lattice-shaped component is advantageously in the optionally present pipe section and / or at the end of the optional pipe section facing away from the vessel

arranged and covered in the direction of the pipe longitudinal axis seen a pipe cross-section of the pipe section.

In a preferred embodiment, at least one modified baffle plate with an opening is present between the vessel and the baffle plate, optionally between the tube section and the baffle plate, wherein a screen or lattice-shaped component is inserted into the opening. Preferably, the

Opening centered to the pipe axis of the optionally existing pipe section arranged.

In this case, at least one modified baffle plate comprising a screen or lattice-shaped component and at least one further screen or lattice-shaped component, optionally in the region of the pipe section of

Gassing device, be present. It has proven useful if a diameter of the opening of the at least one modified baffle plate corresponds to at least one pipe diameter of the optionally present pipe section. As a result, a large part of the gas bubbles, the rising from the pipe section, through the screen or lattice-shaped component of the modified baffle plate (s).

According to the invention, the sieve-like or grid-shaped component comprises at least one sieve element in the form of a braid, woven fabric, knitted fabric or knitted fabric. In combination, the screen or lattice-shaped component may comprise at least one grid element, which is formed from connected tubes, rods or plates.

In particular, the screen or lattice-shaped component is formed from metal or plastic.

Particularly preferably, the sieve or lattice-shaped

Component sieve or grid openings with a diameter in the range of 1 to 10 mm. Impact gas bubbles of larger diameter are reliably cut.

In a particularly preferred embodiment of the invention, the vessel of the gassing device comprises a closed on one side outer tube, which at least one

Has gas inlet opening, and at least one closed on one side inner tube, which has the gas outlet openings, wherein the at least one inner tube in the

Outer tube is arranged, and wherein an open end of the

Outer tube is gas-tight connected to an open end of the at least one inner tube. Such an arrangement allows a particularly intensive fumigation of a suspension in a flotation cell.

The at least one gas inlet opening is included

in particular so arranged on the outer tube, that a radial feed of the gas takes place. This causes the gas along the circumference of the annular gap between the outer tube and inner tube is injected into this and does not bounce directly at right angles to the inner tube. In addition, the

Gas inlet opening preferably arranged near the region in which the open ends of the outer tube and the inner tube connected to each other. This measure (s) lead to a good distribution of the gas in the annular gap and an intensive mixing with suspension in a flotation cell. In a further preferred embodiment, the vessel comprises at least one vane, which in the region between the at least one gas inlet opening and the

Gas outlet openings are arranged and steer the injected gas in a desired direction. For example, a vessel comprising an inner tube and an outer tube may be formed with a vane such that the vane on the inside of the outer tube helically extends from one to the other end of the outer tube. But others too

Arrangements of one or more vanes are possible depending on the configuration of the vessel.

Preferably, only an inner tube is present, which is arranged concentrically to the outer tube. This simplifies the design and lowers the manufacturing cost of the gassing device. Preferably, an optional

existing pipe section and the inner tube on an identical outer and inner diameter and are arranged in alignment with each other. The inner tube has in a particularly preferred

Embodiment of the invention at least one

Gas outlet per square centimeter on. Of the

Diameter of a gas outlet opening is preferably in the range of 1 to 5 mm.

The task is solved for the flotation cell by providing a housing with a flotation chamber, at least one

Nozzle arrangement for supplying gas and a suspension into the flotation chamber and at least one gasification device according to the invention for further supply of gas into the flotation chamber, which in the flotation below the at least one nozzle arrangement such

is arranged that a longitudinal axis of the Fumigation device, which through the center of the

Baffle plate runs vertically aligned.

The flotation cell according to the invention ensures a high separation efficiency and thus yield of valuable material particles, since by means of the at least one gassing device the

Setting appropriate diameter of the gas bubbles in the entire flotation chamber can be achieved. In the

Flotation cell is preferably a

columnar flotation cell, wherein a diameter of the flotation chamber is many times less than its height. In particular, it is a

Hybrid flotation cell, which by a columnar

Flotation cell combined with a pneumatic

Flotation cell is formed. The effect of formation of

Gas bubbles of excessive diameter, which is given here reinforced due to the columnar construction of these flotation cells, by means of the invention

Gassing reliably counteracted. Already existing flotation cells can be equipped in a simple manner with at least one gassing device according to the invention and thereby their performance can be increased. The housing of the flotation cell has, in a preferred embodiment, a cylindrical housing section whose axis of symmetry is arranged vertically.

Gas supply lines, which at least one

Supply gas to gasification device, are preferably passed through the housing.

As gas, which is introduced into a flotation chamber in a pneumatic flotation cell by means of the gassing device and / or the nozzle arrangement, air or nitrogen is preferably used. The object is further achieved for the process for flotation of valuable particles, in particular ore minerals, from a suspension having a solids content in the range of 30 to 40% to form a foam product by means of a flotation cell according to the invention. Such a high one

Solid contents do not lead to clogging of the

Gas outlet openings of the gassing device, since the gas outlet openings in the presence of a sieve or lattice-shaped component can be dimensioned according large.

In particular, a suspension comprising particles having a maximum particle diameter is floated, in which a ratio of the maximum particle diameter of the

Particles to a mesh size of the screen or grid openings of the at least one screen or lattice-shaped component in the range of 1: 5 to 1:10. This ensures that the at least one sieve or lattice-shaped component can not be clogged by particles of the suspension.

Figures 1 to 12 are exemplary gassing according to the invention, a flotation cell and their

Explain how it works. 1 shows a first gassing device in front view; 2 shows the first gassing device according to FIG. 1 in partial longitudinal section;

3 shows the first gassing device according to FIG. 1 and FIG. 2 in section III-III;

4 shows the first gassing device according to FIG. 1 and FIG. 2 in section IV - IV;

5 shows a second gassing device in the longitudinal section ^{¬ section} ;

FIG. 6 shows the second gassing device according to FIG. 5 in FIG

Section VI - VI;

7 shows a third gassing device in the partial longitudinal ^{¬ section} ; 8 shows a part of the pipe section in which a screen or lattice-shaped component is used;

9 shows a view of the two screen or lattice-shaped

Components according to FIG 7 in plan view;

10 shows a fourth gassing device in the partial longitudinal section ^¬;

11 schematically shows a pneumatic flotation cell in

Partial longitudinal section; and

12 shows a plan view of the pneumatic flotation cell according to FIG. 11.

1 shows a first gassing device 1 in the

Front view. FIG. 2 shows the first gassing device according to FIG. 1 in a partial longitudinal section. The first

Fumigation device 1 comprises a vessel 2 with a

Outer tube 2 c, which is an eccentrically arranged

Gas inlet opening 2a for a gas 7 and on one side a closed end 2c 'has. The vessel 2 comprises

Furthermore, an inner tube 2d, which inside and

is arranged concentrically with the outer tube 2c. The inner tube 2d has a closed end 2d 'on one side. The position of the inner tube 2d in the outer tube 2c is shown in FIG 1 by

Dashed lines indicated and in the sectional view of FIG 2 in detail recognizable. The one shown in front view

Inner tube 2d has a number of gas outlet openings 2b, see FIG. 2, and is also shown at its open end via a likewise shown in front view

Connecting element 2e gas-tight with the outer tube 2c

connected. The connecting element 2e has a central opening whose diameter corresponds to the inner diameter of the

Inner tube 2d corresponds. To the connecting element 2e of the vessel 2 here includes a pipe section 3, which is connected via a flange 3b shown in front view gas-tight with the connecting element 2e. The flange 3b also has a central opening, which is arranged in alignment with the opening of the connecting element 2e.

Furthermore, a vessel 2 facing away from the end of

Pipe section 3 associated with a baffle plate 4, whose Plate plane perpendicular to a tube longitudinal axis 3a of the

Tube section 3 is aligned. The baffle plate 4 is dimensioned such that the opening 3e of the tube section 3 is covered as seen in the direction of the tube longitudinal axis 3a. The baffle plate 4 may be attached to the pipe section 3, the vessel 2 or on the inner wall of a flotation cell. However, this is not shown in detail here. Finally, the first gassing device 1, the gas outlet openings 2b downstream and arranged parallel to the plate plane of the baffle plate 4, gas-permeable screen or lattice-shaped component 5, for example in the form of a metal mesh, plastic mesh or the like, see FIG 2. A center of the baffle plate 4 and a center of the at least one screen or lattice-shaped component 5 lie on the tube longitudinal axis 3a of the

Pipe section 3.

If the first gassing device 1 is used in a flotation cell (compare also FIG. 11), suspension to be floated enters the pipe section 3 via the opening 3e and fills it as well as the interior of the inner pipe 2d. Via the gas inlet opening 2a, a gas 7, in particular in the form of air, is introduced with pressure into the outer pipe 2c. The gap between the outer tube 2c and the inner tube 2d fills with the gas 7. Subsequently, the gas 7 flows through the gas outlet openings 2b in the interior of the inner tube 2d and is in the form of gas bubbles in the suspension

introduced, wherein the size of the gas bubbles formed depends on the diameter of the gas outlet openings 2b. The gas outlet openings 2b illustrated in FIG. 2 have a diameter in the range of 3 to 5 mm in order to prevent clogging by particles from the suspension. The im

Inner tube 2 d and the subsequent pipe section 3 ascending gas bubbles pass through the sieve or

grid-shaped component 5 in the pipe section 3, wherein

in particular gas bubbles with a diameter corresponding to the

Mesh size of the screen or grid openings of the screen or grid-shaped component 5 exceeds, be divided. Then enter the gas bubbles whose maximum

Diameter is dependent on the mesh size of the screen or lattice-shaped component, via the opening 3e from the pipe section and are against the baffle plate 4th

hurled and ideally further divided due to the impact and / or intimately mixed with the suspension. On their way through the suspension, the gas bubbles bind

hydrophobized recyclable material per se, rise up to the surface of the suspension and form there

Foamed product comprising the desired valuable particles.

3 shows the first gassing device 1 according to FIGS. 1 and 2 in section III-III. Here is the staggered

Arrangement of the gas inlet opening 2a especially good

detect.

FIG. 4 shows the first gassing device 1 according to FIGS. 1 and 2 in section IV-IV. The screen-like or grid-shaped component 5 completely covers the tube cross-section of the tube section 3.

5 shows a second gassing device 1 'in partial longitudinal section, in which the inner tube 2c, the

Connecting element 2e and the flange 3b in the front view and the remaining components of the second

Begasungseinrichtung 1 'are shown in section. The same reference numerals as in FIGS. 1 to 4 designate the same elements. The second gassing device 1 'has three modified baffle plates 4 a, 4 b, 4 c, which are arranged between the baffle plate 4 and the opening 3 e of the pipe section 3.

The baffle plate 4 and the modified baffles 4 c, 4 b may be on the modified baffle plate 4 a, the pipe section 3, the vessel 2 or on the inner wall of a

Flotation cell be attached. The baffle plate 4, for example, with the modified baffle plate 4c

be bolted, which in turn with the modified Baffle plate 4b can be screwed. The modified one

Baffle plate 4b may be bolted to the modified baffle plate 4a attached to the pipe section 3. The

However, existing options are not available here

Detail shown.

In the pipe section 3, unlike the first gassing device 1, there is no screen or lattice-shaped component. The modified baffle plates 4a, 4b, 4c each have a central opening 6, which are arranged in alignment with the opening 3e of the pipe section and in which a screen or lattice-shaped component 5a is arranged.

Gas bubbles that emerge from the opening 3 e of the pipe section 3, passing through the three screen or lattice-shaped components 5 a through, in particular gas bubbles with a diameter corresponding to the mesh size of the screen or

Grid openings of the respective screen or grid-shaped component 5a exceeds, be divided. Preferably, the sieve or grid openings of the three screen or grid-shaped components 5a are selected smaller with increasing distance from the opening 3e of the tube section 3, so that the smallest possible gas bubbles in the direction of

Get baffle plate 4.

6 shows the second gassing device 1 'in section VI - VI and a plan view of one of the modified

Baffle plates 4a, in the opening 6 a sieve or

grid-shaped component 5a is inserted in the form of a metal wire mesh. The mesh size MW of the metal wire mesh corresponds to the distance between adjacent wires of the fabric.

7 shows a third gassing device 1 "in partial longitudinal section, as already shown in FIGS. 2 and 5.

Like reference numerals denote like elements. In this embodiment, in the pipe section 3 spaced from each other two screen or lattice-shaped components 5, 5 ' arranged, which must pass the ascending gas bubbles. The two screen or grid-shaped components 5, 5 'are formed here, for example, either from the same plastic fabric, wherein the tissue openings of the two

Plastic fabric in particular offset or around the

Pipe longitudinal axis 3a twisted to each other.

Compare here FIG 9, in which an arrangement of the two screen or grid-shaped components 5, 5 'in plan view, in which a rotation of 45 ° to each other is present.

Alternatively, the two screen or lattice-shaped components 5, 5 'made of plastic fabrics formed in their

Different mesh sizes. In this case, the screen or lattice-shaped component 5, which is arranged first in the transport direction of the gas bubbles, preferably has a larger mesh width than the screen or mesh following in the flow direction

grid-shaped component 5 '. In both cases, a

causes particularly effective fragmentation of the gas bubbles.

Furthermore, between the opening 3e of the pipe section 3 and the baffle plate 4 two modified baffles 4b, 4c, each with an integrated sieve or lattice-shaped component 5a present, through which the emerging from the opening 3e gas bubbles are further divided. The

Baffle plate 4 and the modified baffles 4c, 4b can on the pipe section 3, the vessel 2 or at the

Inner wall of a flotation cell, etc. be attached. However, this is not shown in detail here.

8 shows a part of the pipe section 3, for example according to the Figures 2 and 7, in which a sieve or

grid-shaped component 5 is used. If, as shown in Figures 2 and 7, a screen or lattice-shaped member 5 is to be used at some distance from the opening 3e in the pipe section 3e, the pipe section for ease of handling preferably with an insertion opening 3c for

provided lateral insertion of the screen or lattice-shaped component 5, as shown in FIG 8. Furthermore, a fastening device 3d is provided to the sieve or grid-shaped component 5 in the insertion opening 3e to

fix.

9 shows a view of the two screen-like or grid-shaped components 5, 5 'according to FIG. 7 in plan view and has already been described in more detail with reference to FIG.

10 shows a fourth gassing device '' 'in partial longitudinal section, which has no pipe section adjoining the vessel 2 (compare FIGS. 1 to 8). Same

Reference numerals as in FIG. 1 designate the same elements. The fourth gassing device '' 'comprises a vessel 2 with an outer tube 2c, which has a gas inlet opening 2a for a gas 7 and on one side a closed end 2c'. The vessel 2 further comprises an inner tube 2d, which is arranged inside and concentric with the outer tube 2c. The

Inner tube 2d has a closed end 2d 'on one side. The inner tube 2d has a number of gas outlet openings 2b, wherein here at least one gas outlet opening is present per square centimeter. The connecting element 2e has a central opening whose diameter corresponds to the inner diameter of the inner tube 2d. In the opening of the connecting element 2e here is a sieve or

grid-shaped component 5b used. Alternatively, the screen or lattice-shaped component 5b and the

Gas outlet openings 2b to be inserted downstream in the inner tube 2d. Furthermore, here are two modified

Baffle plates 4c, 4b with openings 6 present, in which screen or lattice-shaped components 5a are used.

Furthermore, the vessel 2 is associated with a baffle plate 4, the plate plane perpendicular to a longitudinal axis LA of the

Vessel 2 is aligned. The baffle plate 4 is dimensioned such that the opening in the connecting element 2e is covered. The baffle plate 4 and the modified

Baffle plates 4c, 4d may be on the connecting element 2e, on the vessel 2 or on the inner wall of a flotation cell be attached. However, this is not shown in detail here.

If the fourth gassing device 1 'in a

Flotation cell (see also FIG 11) is used, floats to be floated on the opening in the connecting element 2e and fills the interior of the inner tube 2d. Via the gas inlet opening 2a, a gas 7, in particular in the form of air, is introduced with pressure into the outer pipe 2c. The gap between the outer tube 2c and the inner tube 2d fills with the gas 7. Subsequently, the gas 7 flows through the gas outlet openings 2b in the interior of the inner tube 2d and is in the form of gas bubbles in the suspension

introduced, wherein the size of the gas bubbles formed depends on the diameter of the gas outlet openings 2b.

The gas outlet openings 2b illustrated in FIG. 10 have a diameter in the range of 1 to 5 mm in order to prevent clogging by particles from the suspension. The gas bubbles ascending in the inner tube 2d pass through the sieve-like or grid-shaped component 5b in the connecting element 2e, with gas bubbles in particular having a diameter exceeding the mesh width of the sieve or grid openings of the sieve-like or grid-shaped component 5b being divided.

Then enter the gas bubbles whose maximum

Diameter is dependent on the mesh size of the screen or lattice-shaped component 5b, from the vessel 2 and are guided by the screen and grid-shaped components 5a in the modified baffles 4c, 4b, further divided and finally thrown against the baffle plate 4 and ideally further divided due to the impact and / or intimately mixed with the suspension. On their way through the suspension, the gas bubbles bind hydrophobicized

Recyclable material per se, rise up to the surface of the suspension and form there foam product comprising the desired valuable particles. 11 shows a columnar flotation cell 100, here a hybrid flotation cell, with a housing 110 which has a

Flotationskammer 120 includes. The diameter of the

Flotation chamber 120 is greater than their height. The left side of the flotation cell 100 is shown in front view, the right side in section. Within the

Flotationskammer 120 is a foam channel 130 with nozzle 131 for discharging the foam product formed. The flotation chamber 120 is equipped with at least one nozzle arrangement 140 for supplying gas 8, in particular air, and a suspension into the flotation chamber 120. The suspension here has a high solids content in the range of 30 to 40%. The housing 110 has a

cylindrical housing portion 110a, at the lower end of four gassing assemblies 1 are arranged (only three of them visible). The housing 110 further has a bottom discharge opening 150. The upper edge of the outer wall of the housing 110 is located above the upper edge of the foam channel 130, whereby an overflow of the formed

Foam product over the top edge of the housing 110th

is excluded. Particles of the suspension, the

For example, provided with an insufficiently hydrophobized surface or are not collided with a gas bubbles and hydrophilic particles sink in the direction of Bodenaustragsöffnung 150 and are on this

discharged. By means of the gassing devices 1, additional gas 7, in particular air, is blown into the cylindrical housing section 110a, so that further hydrophobic particles are bound thereto and rise. Ideally, especially the hydrophilic particles continue to sink and are discharged via the bottom discharge opening 150. The foam product containing the valuable material particles passes from the flotation chamber 120 into the foam channel 130 and is discharged via the nozzles 131 and optionally thickened.

FIG. 12 shows the flotation cell 100 in plan view, wherein the position of the gassing devices 1 in the flotation chamber 120 can be seen. In the flotation cell 100, a suspension having a solids content in the range of 30 to 40% comprising particles having a maximum particle diameter is floated, wherein a ratio of the maximum particle diameter of the particles to a mesh MW of the screen or grid openings of the at least one screen or lattice-shaped component 5 in the respective gassing device 1 in the range of 1: 5 to 1:10. This ensures that the at least one screen or lattice-shaped component 5 can not be clogged by particles of the suspension.

The illustrated in Figures 1 to 12

Gassing devices and flotation cells are merely examples of a large number of further possible embodiments of gassing devices according to the invention and flotation cells provided with them. A person skilled in the art can also use other flotation cells with one or a suitable number of gassing devices according to the invention

equip. So can for the use of a

Fumigation device according to the invention suitable

Flotation cells with regard to the design and arrangement of the flotation chamber, the foam collector, the number of

Nozzle arrangements for injecting suspension and gas

without departing from the spirit of the invention. Furthermore, the gassing a different number of gas inlet openings, on sieve or

lattice-shaped components and / or a different number of modified baffles, another arrangement of

Gas inlet (s), other combinations of

Mesh sizes or materials for the sieve or

have lattice-shaped components, various vanes in the vessel of the gassing and the like.

Claims

claims

1. gassing device (1, 1 ', 1' ', 1' '') for a

Flotation cell (100), comprising a vessel (2) with at least one gas inlet opening (2a) and a number of

Gas outlet openings (2b) for a gas (7), and a, the vessel (2) associated baffle plate (4), which in such a way

is arranged so that the gas (7) after leaving the vessel against the baffle plate (4) bounces, and at least one between the gas outlet openings (2) and the baffle plate (4) parallel to the plane of the baffle plate (4)

arranged, gas-permeable screen or lattice-shaped component (5, 5 ^' , 5a, 5b), wherein the screen or lattice-shaped component (5, 5 ^' , 5a, 5b) comprises at least one screen element in the form of a braid, fabric, knitted fabric or knitted fabric ,

2. fumigation device according to claim 1, wherein a to the vessel (2) adjoining pipe section (3) for receiving via the gas outlet openings (2b) exiting gas (7) is present, wherein the baffle plate (4) a the vessel (2) is assigned to the opposite end of the pipe section (3) and a plate plane of the baffle plate (4) is aligned perpendicular to a pipe longitudinal axis (3a) of the pipe section (3), wherein a center of the baffle plate (4) and a center of the at least one screen or lattice-shaped Component (5, 5 ^' , 5a) lie on the tube longitudinal axis (3a).

3. Fumigation device according to claim 1 or claim 2, wherein at least two screen or lattice-shaped components (5, 5 ^' , 5a, 5b) are present.

4. gassing device according to claim 2 or claim 3 in combination with claim 2, wherein a sieve or

lattice-shaped component (5, 5 ^' , 5a) in the tube section (3) and / or at the, the vessel (2) facing away from the end of

Pipe section (3) is arranged and in the direction of

Pipe longitudinal axis (3a) seen a pipe cross-section of the

Covered pipe section (3).

5. Fumigation device according to one of claims 1 to 4, wherein between the vessel (2) and the baffle plate (4)

at least one modified baffle plate (4a, 4b, 4c) having an opening (6) is provided, wherein a screen or lattice-shaped member (5a) is inserted into the opening (6).

6. gassing device according to claim 5, wherein a

Diameter of the opening (6) of the at least one

modified baffle plate (4a, 4b, 4c) at least one

Pipe diameter of the pipe section (3) corresponds.

7. Fumigation device according to one of claims 1 to 6, wherein the braid, fabric, knitted or knit by

Metal wires and / or plastic fibers with diameters up to 1 mm is formed.

8. Fumigation device according to one of claims 1 to 7, wherein the screen or lattice-shaped member (5, 5 ', 5a, 5b) further comprises at least one grid element, which is formed from connected pipes, rods or plates.

9. Fumigation device according to one of claims 1 to 8, wherein the screen or grid-shaped component (5, 5 ', 5a, 5b) screen or grid openings having a diameter in the range of 1 to 10 mm.

10. Fumigation device according to one of claims 1 to 9, wherein the vessel (2) comprises a closed on one side outer tube (2c) having the at least one gas inlet opening (2a), and at least one unilaterally closed inner tube (2d), which comprises the gas outlet openings (2b), wherein the at least one inner tube (2d) in the outer tube (2c) is arranged, and wherein an open end of the outer tube (2c) is connected in a gastight manner with an open end of the at least one inner tube (2d).

11. Fumigation device according to claim 10, wherein only an inner tube (2d) is present, concentric with the

Outer tube (2c) is arranged.

12. Fumigation device according to claim 11, wherein the

Pipe section (3) and the inner tube (2d) have an identical outer and inner diameter and aligned

are arranged to each other.

13. flotation cell (100), in particular columnar

Flotation cell or hybrid flotation cell, comprising a housing (110) with a flotation chamber (120), at least one nozzle arrangement (140) for supplying gas and a suspension into the flotation chamber (120) and at least one fumigation device (1, 1 ', 1' ', 1 '' ') according to one of claims 1 to 12 for the further supply of gas (7) into the flotation chamber (120), which in the flotation chamber (120) below the at least one nozzle assembly (140) is arranged such that a longitudinal axis LA of the

Fumigation device (1, 1 ', 1' ', 1' '') which passes through the center of the baffle plate (4), vertically

is aligned.

14. Flotation cell according to claim 13, wherein the baffle plate (4) of the at least one gassing device (1, 1 ', 1' ',

1 ^''' ) in the flotation chamber (120) above the vessel (2) of the at least one gassing device (1, 1', 1 '', 1 ''') is arranged.

15. Process for flotation of recyclable particles,

in particular ore minerals, from a suspension having a solids content in the range of 30 to 40% to form a foam product by means of a flotation cell (100) according to one of claims 13 or 14.

16. The method of claim 15, wherein a suspension comprising particles having a maximum particle diameter is floated, wherein a ratio of the maximum Particle diameter of the particles to a mesh size MW of the screen or grid openings of the at least one screen or lattice-shaped component (5, 5 ', 5a, 5b) in the range of 1: 5 to 1:10.