JP2011056369A - Magnetic separator, and magnetic separation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic separator having improved capability of capturing particles. <P>SOLUTION: The magnetic separator 1 separates particles present in a fluid by magnetic force, and includes a tubular member 2 comprising an inner wall 11 comprising a coaxial hollow part 11a formed therein, an outer wall 12 comprising a coaxial hollow part 12a formed therein wherein the inner wall 11 is disposed, and a flow path 5 formed between the inner wall 11 and the outer wall 12 for a fluid to flow therethrough; a magnetic-field generator 3 disposed in the hollow part 11a and comprising a plurality of permanent magnets 16, 17; and a filter member 4 that is disposed outside of the magnetic-field generator 3, extends from the center part of the flow path 5 toward the outer circumference thereof, and includes a magnetic body. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a magnetic separation device and a magnetic separation system for capturing and separating particles in a fluid.

  2. Description of the Related Art Magnetic separation devices that capture and separate particles by magnetic force are known. Such a magnetic separation device is often used to separate solid particles in a liquid.

  The magnetic separation methods are roughly classified into open gradient magnetic separation (OGMS) and high gradient magnetic separation (HGMS).

  The open gradient type magnetic separation method is a method in which the magnetic force of a magnet is directly used for separation. The open gradient magnetic separation method is often used for separating iron particles of 1 mm or more.

  On the other hand, the high gradient magnetic separation method is a method in which a wire net made of a thin wire or the like is magnetized by an external magnetic field, and a substance is attracted by a very large magnetic force generated on the surface of the wire. High gradient magnetic separation is often used to separate micron-sized particles.

  In recent years, with the development of superconducting magnet technology, a magnetic field of several T or more can be easily used. For this reason, a magnetic separation apparatus combining a high gradient magnetic separation method and a high magnetic field has been developed. Such a magnetic separation device can separate a ferromagnetic material or a paramagnetic material of 1 μm or less. In addition, the high gradient magnetic separation method has a feature that a wire or the like needs to be put in a flow path, but unlike a magnetic separation device such as a membrane, it is not clogged and cannot be used. That is, the capture performance can be turned on / off by turning the magnetic field on / off. For this reason, when collected matter accumulates in the filter, the magnetic field is turned off to lose the capture performance, and the captured substance can be washed away. This function is effective for recovering valuable materials because the captured material can be easily recovered.

  A permanent magnet is used in a magnetic separation apparatus using an open gradient magnetic separation method. This is because the open-gradient magnetic separation method targets relatively large particles, and does not require a large magnetic force, so that even a permanent magnet having a weak magnetic field can be used. Another reason is that it is inexpensive and requires a strong structure because the magnet and particles directly exert forces.

  On the other hand, an electromagnet is used in a magnetic separation apparatus using a high gradient magnetic separation method. The high gradient magnetic separation method requires on / off of the magnetic field for cleaning the wire mesh, and an electromagnet is used for that purpose. However, in order to process a large amount of water containing fine particles, a large magnetic separation apparatus using a high-gradient magnetic separation method is necessary. However, a large electromagnet is very heavy, and is used for a large amount of power and cooling. Need water. In recent years, superconducting magnets with low running costs have been used, but there is a problem that the equipment becomes very expensive.

  Therefore, Patent Document 1 discloses an aggregating device including a cylindrical body having an annular passage formed therein and a permanent magnet disposed in the annular passage. In this aggregating apparatus, particles are aggregated by a permanent magnet, and the aggregated particles are removed by a filtration device.

Japanese Patent No. 2738522

  However, in the technique of Patent Document 1, it is difficult to spread the magnetic field of the permanent magnet over the entire flow path, and thus particles flowing through the outer periphery of the flow path cannot be aggregated. For this reason, there exists a subject that the particle | grains which flow away from the area | region away from a permanent magnet cannot fully be captured.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a magnetic separation device and a magnetic separation system that can improve the trapping performance of particles.

  In order to achieve the above object, the invention according to claim 1 is a magnetic separation device for separating particles in a fluid by magnetic force, and an inner wall portion in which a first hollow portion is formed, and the inner wall portion is disposed. A tubular member in which a flow path for flowing a fluid is formed between the inner wall portion and the outer wall portion, and a plurality of permanent magnets. The magnetic field generating means provided in the first hollow part, and a filter part disposed outside the magnetic field generating means and from the inner peripheral part to the outer peripheral part of the flow path and including a magnetic substance. .

  According to a second aspect of the present invention, the plurality of permanent magnets include a first permanent magnet and a second permanent magnet arranged so that the first permanent magnet and the magnetic pole face each other. A magnetic member arranged between a permanent magnet and the second permanent magnet is provided.

  According to a third aspect of the present invention, the plurality of permanent magnets include a first permanent magnet and a second permanent magnet arranged so that the first permanent magnet and the magnetic pole face each other. An auxiliary permanent magnet is arranged between the permanent magnet and the second permanent magnet and is magnetized in a direction crossing the arrangement direction.

  According to a fourth aspect of the present invention, the filter unit has a wire mesh including a ferromagnetic material.

  According to a fifth aspect of the present invention, the filter unit includes a plurality of wire meshes including laminated ferromagnetic materials, and the wire mesh is attached so that a surface of the wire mesh intersects a fluid flow. Yes.

  In the invention according to claim 6, the magnetic field generating means or the filter part is removable.

  Further, the invention according to claim 7 is a cleaning in which the magnetic separation device according to any one of claims 1 to 6 and a cleaning liquid for cleaning particles captured by the filter unit are supplied to the flow path. And a mechanism.

  According to the present invention, the magnetic field extending from the permanent magnet is spread to the outer peripheral portion of the flow path by the filter portion including the magnetic material. Thereby, since the particles can be captured also in the outer peripheral portion of the flow path, the particle capturing performance can be improved.

1 is an overall schematic diagram of a magnetic separation system according to a first embodiment. 1 is an overall perspective view of a magnetic separation device according to a first embodiment. It is an internal block diagram of a magnetic separation apparatus. It is a figure explaining the direction of a magnetic field. It is the graph which compared the capture rate of 1st Example with the capture rate of a comparative example. It is a graph of the capture rate by the wire mesh which washed and used repeatedly. FIG. 5 is a view corresponding to FIG. 4 of a magnetic field generation unit according to a second embodiment. It is a top view of the auxiliary permanent magnet of the magnetic force generation part by a 2nd embodiment.

(First embodiment)
Hereinafter, a magnetic separation device and a magnetic separation system according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an overall schematic diagram of a magnetic separation system according to a first embodiment. FIG. 2 is an overall perspective view of the magnetic separation device according to the first embodiment. FIG. 3 is an internal configuration diagram of the magnetic separation device. FIG. 4 is a diagram for explaining the direction of the magnetic field. In the following description, the vertical direction indicated by the arrows in FIG. The direction perpendicular to the vertical direction is defined as the horizontal direction.

  As shown in FIG. 1, the magnetic separation system according to the first embodiment includes a magnetic separation device 1 and a cleaning mechanism 6.

  The magnetic separation device 1 according to the first embodiment separates magnetic particles in a fluid by magnetic force. As shown in FIGS. 2 to 4, the magnetic separation device 1 includes a tubular member 2, a magnetic field generation unit 3, and a filter unit 4.

  The tubular member 2 includes an inner wall portion 11 and an outer wall portion 12. The inner wall portion 11 is formed in a cylindrical shape. A hollow portion 11 a into which the magnetic field generating unit 3 is inserted is formed inside the inner wall portion 11. The outer wall portion 12 is formed in a cylindrical shape. A hollow portion 12 a for arranging the inner wall portion 11 is formed inside the outer wall portion 12. The inner diameter of the outer wall portion 12 is larger than the outer diameter of the inner wall portion 11. And the center of the outer wall part 12 and the center of the inner wall part 11 are arrange | positioned in the substantially the same position. As a result, a flow path 5 is formed between the inner surface of the outer wall portion 12 and the outer surface of the inner wall portion 11 to allow fluid to flow.

  The magnetic field generator 3 generates a magnetic field. The magnetic field generator 3 is detachably provided in the hollow portion 11 a of the inner wall portion 11 of the tubular member 2. As shown in FIG. 3, the magnetic field generation unit 3 includes a housing 15, a plurality of permanent magnets 16 and 17, and a plurality of ferromagnetic members 18.

  The housing 15 is inserted into the hollow portion 11 a of the inner wall portion 11 of the tubular member 2. The housing 15 is formed in a cylindrical shape. A hollow portion 15 a into which the permanent magnets 16 and 17 and the ferromagnetic member 18 are inserted is formed inside the housing 15.

  The permanent magnets 16 and 17 are disposed in the hollow portion 15 a of the housing 15. The permanent magnets 16 and the permanent magnets 17 are alternately arranged. The permanent magnet 16 and the permanent magnet 17 are made of the same cylindrical permanent magnet. However, as shown in FIG. 3, the permanent magnet 16 and the permanent magnet 17 are arranged in opposite directions so that the same magnetic poles face each other. Specifically, the permanent magnet 16 is arranged so that the north pole is on the top. On the other hand, the permanent magnet 17 is arranged so that the south pole is on the top.

  The ferromagnetic member 18 is made of a cylindrical ferromagnetic material. The ferromagnetic member 18 is disposed in the hollow portion 15 a of the housing 15. The ferromagnetic member 18 is arranged between the permanent magnet 16 and the permanent magnet 17. As a result, as shown in FIG. 4, the magnetic field 20 of the permanent magnets 16, 17 extending in the vertical direction is bent in the horizontal direction by the ferromagnetic member 18 and concentrated on the outer periphery of the ferromagnetic member 18. . As a result, the magnetic field 20 is directed to the flow path 5 by the ferromagnetic member 18.

  The filter unit 4 allows the magnetic field 20 extending in the horizontal direction from the magnetic field generation unit 3 to reach far away. The filter unit 4 has a structure in which a plurality of (for example, 200) wire meshes 21 are stacked.

  The metal mesh 21 is formed in a planar ring shape. The inner diameter of the wire mesh 21 is substantially the same as the outer diameter of the inner wall portion 11 of the tubular member 2. The outer diameter of the wire mesh 21 is substantially the same as the inner diameter of the outer wall portion 12 of the tubular member 2. The wire mesh 21 functions as a magnetic circuit that expands the magnetic field 20. The wire mesh 21 is disposed outside the magnetic field generator 3. The wire mesh 21 is disposed from the inner periphery to the outer periphery of the flow path 5. The wire mesh 21 is attached so that the surface of the wire mesh 21 is substantially orthogonal to the direction of fluid flow in the flow path 5. The wire mesh 21 is made of a wire knitted so that the number of meshes is 10 mesh to 100 mesh. The wire constituting the wire mesh 21 is made of stainless steel (for example, SUS430) and has a diameter of 1 mm to 100 μm.

  The cleaning mechanism 6 supplies cleaning water for cleaning the magnetic particles captured by the wire mesh 21 of the filter unit 4 to the flow path 5. The cleaning mechanism 6 is connected to the flow path 5 via the valve 22. The valve 22 switches between a path through which a fluid containing magnetic particles to be captured flows and a path connected to the cleaning mechanism 6.

  Next, the operation of the magnetic separation device 1 described above will be described.

  First, the magnetic fields 20 extending in the vertical direction from the permanent magnets 16 and 17 of the magnetic field generator 3 are repelled and bent as shown in FIG. Further, the bent magnetic field 20 is bent in a substantially horizontal direction by the ferromagnetic member 18, concentrated on the outside of the ferromagnetic member 18, and emitted to the outside of the housing 15 and the inner wall portion 11. Is done. Thereby, the magnetic field 20 extends to the flow path 5 outside the inner wall portion 11. Further, the magnetic field 20 is expanded to the outer wall portion 12 by the wire mesh 21 of the filter portion 4. Thereby, the magnetic field 20 is spread over the entire horizontal plane of the flow path 5, and a large magnetic field gradient is generated. Furthermore, since the magnetic field 20 leaks from the end of the wire constituting the wire mesh 21 at the outer peripheral portion of the wire mesh 21, a large magnetic field gradient is generated. As a result, a large magnetic force is generated in the outer peripheral portion of the flow path 5 where the wire mesh 21 becomes sparse and the pressure loss is lower than that in the central portion.

  In this state, when a fluid containing magnetic particles is caused to flow through the flow path 5 of the tubular member 2, the magnetic particles are captured by the wire mesh 21 by magnetic force. Here, as described above, the magnetic force is large not only in the central part of the flow path 5 in the vicinity of the magnetic field generating unit 3 but also in the outer peripheral part of the flow path 5. Magnetic particles are captured by the wire mesh 21.

  Thereafter, when a predetermined amount of magnetic particles are captured by the wire mesh 21 and the capture performance of the wire mesh 21 is lowered, the magnetic field generator 3 is taken out from the hollow portion 11a and the magnetic field of the wire mesh 21 is lost. In this state, the path is switched by the valve 22. As a result, the cleaning mechanism 6 causes the cleaning water to flow into the flow path 5, and the magnetic particles are detached from the wire mesh 21. When the metal mesh 21 is sufficiently cleaned, the magnetic field generation unit 3 is attached to the hollow portion 11a again. Next, when a fluid containing magnetic particles is passed through the flow path 5, the magnetic particles 21 are captured by the washed wire mesh 21. Thereafter, this capture process is repeated.

  As described above, in the magnetic separation device 1 according to the first embodiment, the wire mesh 21 including a ferromagnetic material is provided from the inside to the outside of the flow path 5. Thereby, since the magnetic field generated from the permanent magnets 16 and 17 of the magnetic field generating unit 3 can be spread to the outer peripheral part of the flow path 5, a magnetic force can be generated in the outer peripheral part of the flow path 5. As a result, the magnetic separation device 1 can capture the magnetic particles in the fluid even in the outer periphery of the flow path 5 where the pressure loss is low and the fluid easily flows. Uniformity can be improved.

  In the magnetic separation device 1, the permanent magnet 16 and the permanent magnet 17 are arranged so that the directions of the magnetic fields are opposite to each other so that the directions of the magnetic fields are opposite to each other. A ferromagnetic member 18 is disposed between the two. Thereby, since the magnetic field generated from the permanent magnets 16 and 17 can be directed in the horizontal direction, the magnetic field can be further spread farther in the flow path 5. As a result, a stronger magnetic force can be generated even in the outer peripheral portion of the flow path 5, so that the capturing performance of the magnetic particles can be improved.

  Furthermore, in the magnetic separation apparatus 1, the magnetic field generation unit 3 is configured to be removable. Thereby, the magnetic field generation part 3 can be removed and the magnetic field extended to the flow path 5 can be lost. In this state, the cleaning mechanism 6 allows cleaning water to flow through the flow path 5, whereby a predetermined amount of magnetic particles can be captured, and the magnetic particles can be separated from the wire mesh 21 whose capture performance has been lowered and cleaned. As a result, the capture performance of the wire mesh 21 of the filter unit 4 can be recovered.

(First experiment)
Next, a first experiment conducted for demonstrating the capture performance of the magnetic particles described above will be described with reference to the drawings. FIG. 5 is a graph comparing the capture rate of the first embodiment and the capture rate of the comparative example.

The first example has the same configuration as the first embodiment described above. The set values and conditions of the first embodiment are as follows.
Diameter of magnetic field generator 3: about 2 cm
Height of magnetic field generation unit 3: about 20 cm
Magnetic field intensity on the surface of the magnetic field generator 3: about 1.4T
Number of meshes of wire mesh 21: 14 mesh Number of layers of wire mesh 21 of filter unit 4: 200 Flow rate of fluid flowing through channel 5: about 7.6 L / min (linear flow velocity: about 30 cm / s)
Width of flow path 5: about 1.2 cm
Particle size of magnetic particles contained in fluid: 1 μm to 10 μm
Magnetic particles in flow channel: magnetite particles The comparative example has the same configuration and the same conditions except that the wire mesh is removed from the first embodiment.

The capture rates of the first example and the comparative example were measured using the set values and conditions described above. The capture rate here is
Capture rate = 1- (magnetic particle concentration after passing through the filter portion / magnetic particle concentration before entering the filter portion)
It is.

  As shown in FIG. 5, in the comparative example, it can be seen that the capture rate is low from the beginning of fluid flow. This is because the comparative example does not provide the wire mesh 21, and in the vicinity of the magnetic field generation unit 3 (that is, the inner peripheral portion of the flow path 5), the magnetic force is strong, so that the magnetic particles can be captured. This is probably because the magnetic force is weak at a distance (that is, the outer peripheral portion of the flow path 5), and it becomes difficult to capture the magnetic particles. Furthermore, in the comparative example, it can be seen that the capture rate decreases rapidly. This is because the magnetic particles are captured by the outer surface of the inner wall portion 11 having a small surface area, so that the occupation ratio of the outer surface of the inner wall portion 11 due to the deposition of the magnetic particles tends to be high, and the inner wall portion 11 quickly becomes saturated. It is done.

  On the other hand, as shown in FIG. 5, in the first embodiment according to the present application, it can be seen that the capture rate is high from the beginning of the fluid flow and is substantially “1”. This is because the magnetic force is strong not only in the vicinity of the magnetic field generating unit 3 but also in the distance since the first embodiment has the wire mesh 21 in the flow path 5. Thereby, since magnetic particles can be captured also in the outer peripheral portion of the wire net 21 (that is, the outer periphery of the flow path 5), it is considered that the first embodiment can realize a high capture rate.

  Furthermore, it turns out that the fall of a capture rate is slow in 1st Example. In the first embodiment, since the magnetic particles are captured by the metal mesh 21 having a large surface area, the occupation ratio of the surface of the metal mesh 21 due to the deposition of the magnetic particles is not easily increased, and it takes time until the metal mesh 21 is saturated. This is probably because of this.

(Second experiment)
Next, a second experiment conducted to verify the recovery performance of the capture performance of the first embodiment described above will be described with reference to the drawings. FIG. 6 is a graph of the capture rate by a wire mesh that has been washed and used repeatedly.

  In the second experiment, the wire mesh 21 was washed three times and the capture rate was measured each time. The cleaning here is performed by removing the magnetic field generation unit 3 from the hollow portion 11 a of the inner wall portion 11 and flowing cleaning water through the flow path 5 as described above.

  As shown in FIG. 6, in the first example, it can be seen that the capture rate after the first cleaning, the capture rate after the second cleaning, and the capture rate after the third cleaning are not substantially changed. Thereby, it turns out that the cleaning performed by removing the magnetic field generation unit 3 is effective in recovering the capture rate.

(Second Embodiment)
Next, a second embodiment in which a part of the above-described embodiment is changed will be described with reference to the drawings. FIG. 7 is a diagram corresponding to FIG. 4 of the magnetic field generator according to the second embodiment. FIG. 8 is a plan view of the auxiliary permanent magnet of the magnetic force generation unit according to the second embodiment. In addition, the same code | symbol is provided to the structure similar to embodiment mentioned above, and description is abbreviate | omitted.

  As shown in FIG. 7, the magnetic field generator 3 </ b> A according to the second embodiment includes an auxiliary permanent magnet 25 between the permanent magnet 16 and the permanent magnet 17. Here, the direction of the magnetic field of the auxiliary permanent magnet 25 is configured in the radial direction as shown in FIG. The direction of the magnetic field of the auxiliary permanent magnet 25, that is, either from the center to the outer periphery or from the outer periphery to the center, is set by the direction of the magnetic field of the permanent magnets 16 and 17 arranged on both sides of the auxiliary permanent magnet 25. . Thereby, a magnetic field can be concentrated on the outer peripheral part of the auxiliary | assistant permanent magnet 25, and a magnetic field intensity | strength can be improved more.

  Since the second embodiment has the same configuration except that the ferromagnetic member 18 of the first embodiment is changed to the auxiliary permanent magnet 25, the same effect as that of the first embodiment can be obtained.

  As mentioned above, although this invention was demonstrated in detail using embodiment, this invention is not limited to embodiment described in this specification. The scope of the present invention is determined by the description of the scope of claims and the scope equivalent to the description of the scope of claims. Hereinafter, modified embodiments in which the above-described embodiment is partially modified will be described.

  For example, the configuration, shape, numerical value, material, and the like of the above-described embodiment can be changed as appropriate.

  In the above-described embodiment, the filter unit is configured by a wire mesh, but the filter unit may be configured by a bundle of wires.

  In the embodiment described above, the magnetic field generation unit is configured to be removable, but the filter unit may be configured to be removable.

DESCRIPTION OF SYMBOLS 1 Magnetic separation apparatus 2 Tubular member 3, 3A Magnetic field generation part 4 Filter part 5 Flow path 6 Washing mechanism 10 Magnetic separation system 11 Inner wall part 11a Hollow part 12 Outer wall part 12a Hollow part 15 Case 15a Hollow part 16, 17 Permanent magnet 18 Ferromagnetic material 20 Magnetic field 21 Wire mesh 25 Auxiliary permanent magnet

Claims (7)

In a magnetic separation device for separating particles in a fluid by magnetic force,
An inner wall portion formed with a first hollow portion, and an outer wall portion formed with a second hollow portion where the inner wall portion is disposed, for flowing a fluid between the inner wall portion and the outer wall portion. A tubular member in which a flow path is formed;
A magnetic field generating means having a plurality of permanent magnets and provided in the first hollow portion;
A magnetic separation device comprising: a filter unit disposed outside the magnetic field generation unit and extending from an inner periphery to an outer periphery of the flow path and including a magnetic substance. The plurality of permanent magnets are:
A first permanent magnet;
A first permanent magnet and a second permanent magnet arranged so that the magnetic poles face each other;
The magnetic separation apparatus according to claim 1, further comprising a magnetic member arranged between the first permanent magnet and the second permanent magnet. The plurality of permanent magnets are:
A first permanent magnet;
A first permanent magnet and a second permanent magnet arranged so that the magnetic poles face each other;
2. The magnetic separation device according to claim 1, further comprising an auxiliary permanent magnet arranged between the first permanent magnet and the second permanent magnet and magnetized in a direction crossing the arrangement direction. The filter section is
The magnetic separation device according to claim 1, further comprising a wire mesh including a ferromagnetic material. The filter section is
A plurality of wire meshes including laminated ferromagnetic materials are provided,
5. The magnetic separation device according to claim 1, wherein the wire mesh is attached so that a surface of the wire mesh intersects with a fluid flow.   The magnetic separation apparatus according to claim 1, wherein the magnetic field generation unit or the filter unit is detachable. The magnetic separator according to any one of claims 1 to 6,
A magnetic separation system comprising: a cleaning mechanism that supplies a cleaning liquid for cleaning particles captured by the filter unit to the flow path.