JPH04225809A - Wet strong magnetic separator - Google Patents

Abstract

PURPOSE: To aim at reducing weight, volume, price and energy consumption which is the factors of detects in a prior art by using permanent magnets instead of electromagnets utilized in a magnetic separator operating in wet environment. CONSTITUTION: A separating chamber 10 is arranged between two bipolar magnets 12. The separating chamber 10 is made of nonmagnetic material, having a sectional area of rectangular and a casing with openings at both ends, wherein weak magnetic elements of a bar shape or the like is housed. The magnets 12 have a jack 34, which makes the magnetic to be contactable and detachable to an external wall of the separating chamber 10. Tubes 16, 20 to supply with article from which magnetic powders are removed and with water, are connected to the upper part of the separating chamber 10. A collector 24 is connected with a bottom of the separating chamber 10, downstream therefrom with a product takeout and magnetic powder discharge pipe 26, 28.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention comprises at least one separation chamber through which a liquid or pulp product to be treated, in which particles to be separated are suspended, passes from above to below; a magnet or a coil that generates a magnetic field with lines of force perpendicular to the flow direction in the chamber, and the separation chamber is made of a grooved plate, a ball, expanded metal, stale wool, etc., and the product to be treated The present invention relates to a wet ferromagnetic separation device that is capable of containing a circulating matrix.

0002

BACKGROUND OF THE INVENTION Discontinuously operating separators of this type are operated in a cyclic manner as follows. First, in the first phase, the product to be treated is circulated in a separation chamber in which a magnetic field is present, and in this phase, the magnetic particles of the product are fixed to the walls of the chamber and/or the elements of the matrix, and the non-magnetic particles are moved by the liquid phase of the product. and collect it in the first collector. In the second phase, the supply of product to be treated is stopped, the magnetic field is removed, and the magnetic product is evacuated from the separation chamber by flushing with a pressurized liquid, typically water.

[0003] In this device, it is customary to use a coil to generate a magnetic field that makes it possible to cancel the magnetic field during the cleaning phase. However, proposals have been made to use permanent magnets in filters of the type that are cleaned with liquids that have little magnetic particles and do not require frequent cleaning. In such filters, the separation chamber is constituted by a cassette which, in case of blockage, can be replaced with another cassette, possibly after removal of the magnet. Filters of this type are unsuitable for processing products containing magnetic particles.

In continuously operating separation devices, a plurality of separation chambers are assembled to form an endless chain or ring and are continuously moved relative to fixed pole members perpendicular to the magnetic field lines. During the movement, the chamber passes sequentially through a separation zone, a washing zone and a magnetic component evacuation zone. The feeding of the chamber takes place in the separation zone, in fact over the entire length of said zone. At the outlet of the zone, where the magnetic field is still strong, a cleaning liquid is circulated into the chamber to evacuate the non-magnetic component grains held by magnetic agglomeration. Following the washing zone, in a discharge zone where the magnetic field is virtually zero, the magnetic product is discharged by washing with pressurized water.

[0005]

Such devices are heavy, bulky and expensive, and because the magnetic field is generated by an electromagnet, they consume a lot of power. The use of permanent magnets instead of electromagnets in this type of device has been proposed, but the strength of the magnetic field that can be produced with permanent magnets is limited, and the relative movement of the walls of the separation chamber and the magnet or pole members is limited. The use of permanent magnets in devices of this kind has not been realized because of the need for a gap between them to allow for.

An object of the present invention is to provide a wet ferromagnetic separator using permanent magnets instead of electromagnets, thereby making it possible to reduce weight, volume, cost, and energy consumption, which are disadvantages of conventional devices. It is something to do.

[0007]

SUMMARY OF THE INVENTION The magnetic separation device which is the object of the invention comprises at least one separation chamber, in which the product to be treated circulates from above to below, and a permanent magnet, optionally connected to a pole member. and a first position in which the magnet and pole member are pressed tightly against the wall of the separation chamber, and a first position in which the magnet and pole member are separated from the wall and the magnetic field in the chamber is so weak that the magnetic product can be ejected from the chamber by the flow of cleaning liquid. and a device for moving the magnet and pole member across the flow direction of the product to be processed between a second position and a second position.

The magnets are movable by jacks controlled by programmable automatic devices and valves in the supply and discharge parts of the separation chamber, and are pressed against the walls of the chamber during the separation phase, and the magnetic component during the evacuation phase, the duration of each phase being determined, for example, depending on the degree of clogging of the chamber.

The separation chamber of the present invention can be conventionally constructed of a tubular casing of non-magnetic material containing a matrix formed of grooved plates, balls, expanded metal, etc., occupying the entire cross section of the chamber.

Similarly, the separation chamber normally has a circular or medium-height cross section, and is made of an elastically deformable material such as rubber or plastic material so that it is pressed between magnets and becomes a flat tube during the separation phase. It can be constructed from a cylindrical tube.

[0011] The magnet can be constructed by an assembly of elementary magnets with a direction of magnetization perpendicular to the flow direction of the product to be processed in the separation chamber.

It is likewise possible to use a polymer of magnet and flat pole element, the magnetization direction of the magnet being parallel to the flow direction of the product to be treated. The pole members on both sides of the separation chamber may be of the same or opposite polarity in the same plane perpendicular to the direction of flow of the product to be processed, or they may be vertically offset by half a pitch.

[0013] If the separation device is equipped with only a single separation chamber, the operation is necessarily intermittent. For continuous operation, several identical basic devices are coupled together, each device having a separate chamber, a permanent magnet or, if necessary, a pole member, and a permanent magnet separated from the chamber or pressed against the chamber wall. A plurality of devices are connected so as to be able to operate continuously by supplying products to be treated and cleaning liquid in a circulating manner.

A plurality of fixable devices can first be connected to a supply of product to be treated and a collector of washed product and then programmed to open and close to ensure cyclical operation of the separation device. A source of cleaning fluid and a collector of the magnetic component can be connected through the gap in the valve.

The separation device is likewise movable and moves between a separation zone with a supply of the product to be treated and a collector of the washed product and a washing zone with a wash liquid distribution device and a collector of the magnetic component. In installations with only two devices, the movements are alternated.

Generally, the separating devices are interconnected to form an endless chain or ring, or are always moving progressively in the same direction. Naturally, a plurality of separation and cleaning zones can be provided along the endless chain or ring. According to the invention, when the device transitions from one zone to another, the magnet moves laterally with the longitudinal movement of the device.

Alternatively, two or more chambers of each device are introduced successively between magnets in a separation zone, which further comprises a feed for the product to be treated and a collector for the cleaning product, and then separated from the zone. The magnets, which are normally pressed against the chamber walls, are introduced into the separation zone with periodic movement away to enable movement of the chamber.

Since the magnets and/or pole members on either side of the separation chamber have opposite polarities, the device used to separate the magnets from the separation chamber must be able to overcome the magnetic attraction. During the approaching movement of the magnets or pole pieces, part of the starting energy can be recovered, especially when using several devices operating in succession.

[0019]

BRIEF DESCRIPTION OF THE DRAWINGS Other features and advantages of the invention will be explained in more detail below with reference to the accompanying drawings, which illustrate, by way of non-limiting example, embodiments of the invention.

The separation device shown in FIGS. 1 and 2 mainly consists of a separation chamber 10 located between two magnets 12, 12 of bipolar nature. Each magnet is connected to an armature 14 of L-shaped cross section, the two armatures being arranged so that the magnets are connected to the chamber 10 as shown in Figure 2a.
When pressed against the opposing wall of the chamber 10, it forms a magnetic closed circuit with the magnet and the chamber 10.

The separation chamber is constituted by a casing made of non-magnetic material and having a rectangular cross section and open at both ends. The chamber is equipped with a number of grooved vertical plates or other elements, such as rods of weakly magnetic material or hammer scales, which generate a magnetic field with a gradient that allows the magnetic particles of the product to be treated to stick to the elements, in the gap between the magnetic poles. cause to occur.

The upper end of the chamber 10 is connected via a solenoid valve 18 to a pipe supplying the product to be treated, and via a solenoid valve 22 to a pressurized water pipe 20 . Collector 24 is located below chamber 10 and is connected to two pipes 2 via solenoid valves 30 and 32, respectively.
6 and 28 to direct the collected product in two different directions.

The jack 34 is capable of moving the magnet and armature perpendicularly to the wide surface of the chamber 10, and can hold the magnet in contact with the surface (FIG. 2a) or away from the surface (FIG. 2b). .

The separation apparatus of the present invention operates as follows. In the first phase, when the magnet 12 is brought into contact with the broad surface of the chamber 10 (FIG. 2a), the valves 18, 30 open and the valves 22, 32 close. The product in pulp form to be processed is circulated in the chamber 10 between vertical plates from top to bottom. The magnetic particles move toward the plate under attractive force and are held there. The purified product is collected in collector 24 and discharged via tube 26.

In the second phase, when the magnet leaves the chamber (FIG. 2b), valves 18, 30 are closed and valves 22, 32 are open. The magnetic particles, which are no longer under the influence of the magnetic field, are therefore swept away by the pressurized water circulating in the chamber 10 and are discharged via the tube 28.

The duration of the first phase can be predetermined, especially if the magnetic particle content of the product to be treated changes little over time. Alternatively, the transition from the first phase to the second phase may occur when the degree of clogging of the chamber, estimated for example by the degree of flow rate or head loss, reaches a predetermined value.

The magnets must be separated by a sufficient distance so that the magnetic field in chamber 10 is practically zero, so that the field lines of each magnet are such that they create a magnetic field gradient between the magnet and the inner surface of the tube. Good too. Figure 3a corresponds to the separation phase, the magnets are close together and the tube 110 is crushed. In the cleaning phase (FIG. 3b), the magnets separate from each other and the tube becomes circular.

[0028] In order to enable continuous processing of products, it is necessary to cooperate with a plurality of separation devices. In the normal case where the cleaning phase is shorter than the separation phase, 2
one device is sufficient.

A schematic diagram of such equipment is shown in FIG. The supply pipe for the product to be treated and the pressurized water supply pipe 20 are each connected to a valve 1.
8' and 18'' and 22' and 22'' with the chambers 10' and 10''. Collector 24' and 24'' below the chambers 10' and 10'' collect the product leaving the chamber for cleaning. It can be directed along the position of the selector shown schematically by the pivoting flaps 50', 50'' towards the finished product outlet or the magnetic product outlet.

Jacks (not shown) for moving the valves 18', 18'', 22', 22'', selectors 50', 50'' and magnets 12', 12'' are preset so that at least one device is always in the separated phase. It will be reclosed through the magnetic pole gap between the automatic device or microcomputer room 10 and the cooperating armature according to a set and changeable program.

The magnet 12 is constructed by assembling magnets whose constituent elements are samarium-cobalt or neodymium-iron-boron by adhesive, and the direction of magnetization is perpendicular to the wide surface of the chamber 10. Alternatively, as shown in FIG. 4, a stack of a magnet 40 and a magnetic member 42 may be used instead of each magnet 12-armature 14 assembly, in which case the magnetization direction of the magnet is It is parallel to the flow direction of the product to be processed in the chamber 10 (arrow F).

FIGS. 3a and 3b show an alternative embodiment of the separation chamber of the invention. Here, the chamber is constituted by an elastically deformable tube 110 made of rubber or plastic material, usually of circular cross-section (FIG. 3b) and flattened when compressed between the magnets 12 (FIG. 3a). The tube may be deformed or
A material such as hammer scale is filled in such a way that it can be elastically compressed without much force to restore the deformed object to its original state. It is controlled by longitudinally arranged or braided wires of weakly magnetic material embedded in the thickness of the tube wall to form a tubular duct.

The number of devices used in a facility depends on the amount of product to be processed. Economical using standard equipment;
It is also easy to maintain, and inconvenient equipment can be quickly replaced.

An intermediate water washing phase may be provided while the magnetic field is maintained in order to remove particles of non-magnetic components retained by magnetic coagulation. Although the embodiments of the present invention have been described above, it goes without saying that the device and parts of the present invention can be replaced with other suitable devices that are technically equivalent without departing from the scope of the present invention. Please note.

[0035]

[Effects of the Invention] As explained above, according to the present invention,
Since a permanent magnet is used instead of an electromagnet in the magnetic force generator of the wet ferromagnetic separator, the weight, volume, cost, and energy consumption can be reduced compared to conventional devices.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view schematically showing a separation device according to the invention.

2a and 2b are top views of the apparatus of FIG. 1 during a separation phase and a washing phase, respectively; FIG.

3 is a top view similar to FIGS. 2a and 2b, showing another type of separation device according to the invention with a separation chamber according to a different concept; FIG.

4 shows a possible embodiment of the magnetic circuit of the separation device; FIG.

FIG. 5 shows a possible connection of two separation devices to ensure continuous operation;

[Explanation of symbols]

10,110 Separation chamber 12
magnet 14
Pole members 16, 20
, 26, 28 Pipe 18, 22, 30, 32 Valve

Claims (9)

[Claims] 1. At least one separation consisting of a chamber in which the product to be treated circulates from above to below and a device for generating a magnetic field perpendicular to the direction of flow of the product to be treated. A wet ferromagnetic separation device including the device,
The device for generating a magnetic field may optionally include a pole member (1
a first position in which the magnet or pole member is pressed tightly against the wall of the chamber (10) and a first position in which the magnet or pole member is separated from the wall and in contact with the chamber (10);
10) Providing a device (34) for moving the magnet and possibly the pole piece between a second position in which the magnetic field within is so weak that the magnetic particles can be evacuated from the chamber by the flow of cleaning liquid; The magnetic separation device is characterized by: 2. The device for moving the magnet (12) and optionally the pole pieces is provided in a valve provided in the pipe (16, 20, 26, 28) connecting the inlet and outlet of the chamber (10). (18, 22, 30, 32) together with a jack (34) controlled by a programmable automatic device or a microcomputer so that the magnet, or possibly the pole member, is in the chamber during the separation phase. 2. A magnetic separation device as claimed in claim 1, characterized in that it is pressed against a wall and moves away from said wall during the washing phase. 3. Magnetic separation device according to claim 1, wherein the chamber (10) is constituted by a tubular case made of non-magnetic material containing a ferromagnetic matrix through which the product to be treated is transparent. 4. The chamber (110) is made of an elastically deformable material, usually having a circular or medium-height cross section, by means of a cylindrical tube containing a ferromagnetic matrix that is elastically compressible and passes through the product to be treated. 3. A magnetic separation device as claimed in claim 1 or claim 2, characterized in that during the separation phase the tube is pressed between the magnets or pole members into a flat tube shape. 5. The apparatus for generating the magnetic field is characterized in that the device for generating the magnetic field is constituted by an assembly of elementary magnets having a direction of magnetization perpendicular to the direction of flow of the product to be treated in the chamber (10). 4. The magnetic separation device according to any one of 4. 6. The device for creating a magnetic field is constituted by a stack of magnets and pole pieces, the magnetization direction of the magnet being parallel to the flow direction of the product to be treated in the chamber (10). A magnetic separation device according to any one of claims 1 to 4, characterized in that: 7. The or each separation device comprises two or more chambers, a first zone comprising the magnet and a device for supplying the product to be treated and collecting the cleaned product, and a first zone for distributing the cleaning liquid and for distributing the magnetic particles. The chamber is placed between the first zone and the second zone, which is provided with a device for collecting the
Magnetic separation device according to any of the preceding claims, characterized in that it includes means for moving one zone after another into a second zone, and means for adjusting the movement of said chamber and said magnet and/or pole member. 8. A plurality of separation devices, each separation device comprising a supply device (16) for products to be processed, a collector (26) for washed products, a source of cleaning liquid (20), and a collector (28) for magnetic particles. (18', 18
7. A magnetic separation device according to any one of claims 1 to 6, comprising: 9. A separation zone comprising a plurality of separation devices and a device for supplying the product to be treated and collecting the washed product, and then a washing zone comprising a device for distributing the washing liquid and collecting magnetic particles. 7. A magnetic separation device according to claim 1, further comprising a device for introducing said separation devices one after another.