JP2861866B2 - Activated sludge magnetic separator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an activated sludge magnetic separation apparatus for separating and recovering activated sludge from activated sludge using magnetic force.

[0002]

2. Description of the Related Art Conventionally, as a method for separating an activated sludge such as sewage into activated sludge and treated water, instead of spontaneous settling, as disclosed in JP-A-48-42570, A method has been proposed in which magnetic powder is added to and mixed with activated sludge, and the mixture is passed through a magnetic field to aggregate the activated sludge and promote solid-liquid separation of the activated sludge.

However, since this method is also a solid-liquid separation method based on natural sedimentation, it requires a large sedimentation separation layer and cannot be continuously processed, and takes a long time for solid-liquid separation. have. For this reason, in Japanese Patent Publication No. 63-59759, as shown in FIG. 9, the activated sludge solution A containing the magnetic powder is drawn out of the aeration tank b into the separation tank c by a slurry pump a or the like. The activated sludge B containing the magnetic powder in the activated sludge liquid A is magnetically adsorbed by a magnetic separation roller f provided with a magnet e around a roller d, and is actively separated into solid and liquid. There has been proposed an activated sludge separating apparatus in which sludge B is returned into the aeration tank b again.

[0004]

As shown in the figure, the activated sludge separating apparatus includes a magnetic separation roller f for adsorbing and separating activated sludge B, and a magnetic separation roller f in a box-shaped separation tank c having a flat bottom. A configuration is provided in which a part of the activated sludge liquid A is soaked in the flowing activated sludge liquid A. Therefore, since there is a region where the magnetic force from the magnetic separation roller f does not act on the activated sludge B in the separation tank c, it has been difficult to efficiently adsorb and separate the activated sludge B in the separation tank c.

Accordingly, the present invention has been devised in order to effectively solve the above problems, and a purpose of the present invention is to provide a novel method capable of efficiently adsorbing, separating and recovering activated sludge in an activated sludge liquid. It is an object of the present invention to provide a magnetic separation device for activated sludge.

[0006]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 is directed to a part of a rotating drum having a magnet facing a flow path through which an activated sludge liquid to which magnetic powder is added flows. Then, in the activated sludge magnetic separation device for magnetically adsorbing the activated sludge with the magnet and separating and recovering the activated sludge and the treated water, the lower outer periphery and the side surface of the rotating drum are provided at the lower portion of the rotating drum. Forming a curved channel to cover,
On the outer periphery of the rotating drum, a flange-shaped magnetic adsorbing member that partitions the flow path into the right and left directions in the flow direction is provided. It is a thing.

According to a second aspect of the present invention, the magnetic attraction member comprises:
A plurality of magnet bodies are arranged along the circumferential direction of the flange formed on the outer periphery of the rotary drum such that the respective magnetic poles are located on the left and right flow path sides.

According to a third aspect of the present invention, the rotary drum includes a disk having the magnet body on an outer peripheral portion, and a drum plate supporting both sides of the disk.

According to a fourth aspect of the present invention, the plurality of magnets are provided on the outer peripheral portion of the disk along the circumferential direction such that the magnetic pole faces are located on the disk surface and the polarity of each magnet is Are provided so as to be the same on the disk surface.

According to a fifth aspect of the present invention, both sides of the plurality of disks are supported by the drum plate, and the magnetic attraction members on the outer periphery of the disks partition the plurality of channels and sandwich the partitioned channels. The magnetic poles of the magnetic attraction members opposed to each other are provided so as to have different polarities.

[0011]

According to the present invention having the above-described structure, a flow path defined in an arc shape along the magnetic attraction member is formed by the outer periphery of the rotary drum and the magnetic attraction member. Therefore, by flowing the activated sludge liquid to which the magnetic powder is added into the flow path, the magnetic force of the magnetic adsorption member that partitions the flow path surely acts on the activated sludge liquid, so that the activated sludge is effectively applied to the magnetic adsorption member. Can be adsorbed. The activated sludge adsorbed on the magnetic adsorption member is continuously separated and collected from the magnetic adsorption member by the scraping member provided on the upper portion of the rotary drum as the rotary drum rotates. Further, this magnetic attraction member is formed by a flange or a disk of a rotating drum, and a plurality of magnet bodies are arranged along the circumferential direction such that respective magnetic poles are located on the left and right flow path sides, The magnetic forces of the individual magnets act on the flow path all over, and all the magnetic forces of the magnets can be used effectively.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 8 shows an example of a conventional sewage treatment process. This sewage treatment process 11 mainly includes a water treatment system 12 and a sludge treatment system 13.

In the water treatment system 12, the sewage pumped by the pump 14 passes through a sand basin 15, a sedimentation basin 16, an aeration tank (aeration tank) 17 and a magnetic separation device 18.
It is recycled through the tertiary treatment equipment 19 or discharged through the sterilization layer 21. In the aeration tank 17, sludge liquid reacts with microorganisms to be organically decomposed, and aeration air is sent from an aeration blower 22 to further promote the decomposition. Magnetic powder is added and mixed into the aeration tank 17 in order to facilitate solid-liquid separation of the activated sludge liquid. Excess sludge discharged from the sedimentation basin 16 and the magnetic separation device 18 via the pump 23 is supplied to the sludge treatment system 13.
The sludge treatment system 13 includes a sludge concentrator 24, a sludge centrifugal concentrator 25, and a sludge digestion tank 2 for sludge treatment.
6. A gas holder 27, a belt press 28, a centrifugal dehydrator 29, a sludge incinerator 31, and the like are installed.

The magnetic separator 18 of the present invention will be described in detail with reference to FIGS.

FIG. 1 is a side view showing the magnetic separation device 18, FIG. 2 is a plan view thereof, and FIG. 3 is a view taken along the line DD in FIG.

As shown in FIG.
A rotating drum body 3 is rotatably supported on a frame body 2 in which a flow path 1 through which the activated sludge solution A flows is formed,
A drive motor 6 is connected to the rotating shaft 4 via a coupling 5.
Is connected, and the rotary drum body 3 is driven to rotate clockwise in FIG. The flow path 1 is formed in a gutter shape and a U-shaped cross section. Further, a curved flow curved concentrically along the outer periphery of the rotary drum body 3 is provided at a portion where the rotary drum body 3 faces. A road 1a is formed. Further, a flange-shaped magnetic attraction member 7 is formed at the center of the outer periphery of the rotary drum body 3 and protrudes outward in the radial direction of the rotary drum body 3. As shown in FIG. The activated sludge B in the activated sludge liquid A flowing through the curved flow path 1a is adsorbed on both sides thereof.

The magnetic attracting member 7 has a flange 7b formed integrally with the rotary drum 3 by injection molding using a thermoplastic resin or the like.
As shown in FIG. 1, for example, a columnar magnet body 7a is formed in the circumferential direction of the rotating drum body 3 and, as shown in FIG. The magnetic poles are arranged continuously so as to be located on the curved flow paths 1a and 1a sides, and the magnetic pole portion having the strongest magnetic force faces the respective curved flow paths 1a and 1a, thereby effectively applying the magnetic force. It has become.

A pair of scraping members 8, 8 are provided above the rotary drum 3 so as to sandwich the magnetic attraction member 7 from the left and right. As shown in the drawing, the scraping members 8 and 8 are formed by fixing a gutter-shaped member having a U-shaped cross section to the frame body 2 by inclining the sludge B. It is scraped and returned to the aeration tank 17 side.

Next, the operation of this embodiment will be described.

As shown in FIGS. 1 and 2, the activated sludge liquid A sent from the aeration tank 17 flows horizontally through the flow path 1 formed in the frame body 2 and then flows into the curved flow path 1a. Flows to In the curved flow path 1a, the magnetic attraction member 7 protruding from the outer periphery of the rotary drum 3 faces along the curved flow path 1a and is divided into left and right in the flow direction. The activated sludge liquid A flowing to the side 1a acts uniformly. As a result, the activated sludge B in the activated sludge liquid A attracts the magnetic powder contained therein to the magnet 7a of the magnetic adsorption member 7, and FIG. 3 and FIG.
As shown in (2), it is separated from the activated sludge liquid A and is adsorbed in a lump on the surface of the magnetic adsorption member 7. At this time, since the rotating drum 3 is driven to rotate clockwise in the figure, the activated sludge B adsorbed by the magnetic attraction member 7 is transported above the rotating drum 3 with the rotation of the rotating drum 3, and the activated sludge liquid is activated. Separated from A. The magnetic poles of the respective magnet bodies 7a constituting the magnetic attraction member 7 have respective curved flow paths 1a,
Since the magnets are arranged so as to face the side 1a, the magnetic force of each magnet body 7a effectively acts on the side of the curved flow path 1a, and efficient adsorption is performed. On the other hand, the activated sludge liquid A from which the activated sludge B has been separated becomes treated water C and is discharged from the end of the flow channel 1 and then subjected to a sterilization treatment or the like downstream thereof as necessary. .

The activated sludge B adsorbed by the magnetic adsorption member 7 is scraped off by the scraping members 8, 8 abutting on both sides of the magnetic adsorption member 7 above the rotary drum 3 transferred upward together with the rotary drum 3. After being continuously scraped off from the magnetic attraction member 7 by this, it flows down along this inclination, and again the aeration tank 1
It is returned to the side 7 and used for organic treatment such as waste water.

As described above, according to the present invention, by forming a curved flow path along the rotating drum for magnetically adsorbing activated sludge, it is possible to uniformly apply a magnetic force to the activated sludge flowing therethrough. Therefore, the separation efficiency of activated sludge by magnetic adsorption can be greatly improved.

Next, another embodiment of the present invention will be described.

FIG. 5 shows an example in which the rotary drum 3 of FIG. 4 is modified. .

In FIG. 4, the magnet body 7a is arranged in the circumferential direction of the flange 7b of the rotating drum 3 and at the respective magnetic poles (NS
Pole) is the side surface of the magnetic attraction member 7, that is, the curved flow path 1
a, the magnetic attraction members 7 are arranged continuously so as to be positioned on the side of 1a, but in this example, the magnetic attraction members 7 of the rotary drum 3 are formed of thin disks as shown in FIG. The rotating drum 3 and the magnetic attraction member 7 are formed independently by arranging a drum plate 50 also formed of a thin disk on both sides so as to sandwich the disk 40. .

As described above, since the magnetic attraction members 7 of the rotating drum 3 are formed independently, the structure of the apparatus is simplified, and when a plurality of disks 40 are arranged in parallel in the flow direction of the flow path 1 on the left and right. The device can be easily formed.

FIG. 7 is a diagram showing an example of the disk 40 described in FIG.

The disk 40 shown in FIG. 7A uses a rubber-like sheet magnet (for example, a ferrite magnet which is alternately magnetized in a belt shape at intervals of 5 mm). By arranging the sheet magnets in parallel, the size of the disk 40 is not limited. However, as shown in FIG. 7B, N and S magnetic poles are alternately arranged on the same plane. For,
The magnetic field lines M return near the surface of the magnet, and there is a disadvantage that the range over which the magnetic field reaches is narrow.

FIG. 7 (C) shows a case where the entire disk 40 is a magnet, and a disc-shaped magnet such as ferrite is used for the magnet, and N and S magnetic poles are unified on the front and back surfaces of the magnet. It is arranged.

FIG. 7 (D) shows an arrangement in which a large number of small cylindrical magnet bodies 7a are arranged at intervals on the outer periphery of a disk 40 made of synthetic resin or Al. For example, an Nd-Fe-B magnet or the like is used, and N and S magnetic poles are unified on the front and back surfaces of the magnet.

As shown in FIG. 7 (E), since the magnetic poles of N and S are unified on the front and back surfaces of the disk 40 as shown in FIG. Does not return near the surface of the magnet, and the range of the magnetic field is widened.

Further, the disk 40 shown in FIG.
It is particularly preferable to use a sintered magnet typified by a Nd-Fe-B magnet having the highest coercive force at present, as the magnet bodies 7a arranged along the circumferential direction of FIG.

When the size of the rotary drum 3 is increased, it is needless to say that the magnets 7a are appropriately disposed on the disk 40 in accordance with the size of the magnets 7a which can be formed.

FIG. 6 shows a further modified example of FIG.
An example is shown in which the rotating drum 3 is configured by providing the disk 40 and the drum plate 50 in multiple stages.

In this embodiment, if the number of the magnetic adsorption members 7 formed by the disks 40 is plural and arranged in parallel to the left and right in the flow direction of the flow path 1, the activated sludge liquid per unit area of the magnetic adsorption members 7 Since the volume of A is reduced, the efficiency of removing activated sludge B is improved, and the cross-sectional area of the flow channel can be increased, so that the throughput of activated sludge can be increased.

When a plurality of magnetic attraction members 7 are arranged parallel to the flow direction of the flow path 1 in the left and right direction, if the magnetic attraction members 7 of the rotating drum 3 are formed independently, as shown in FIG. The relationship with the plate 50 is that the disk 40 is sandwiched between the drum plates 50, that is, a sandwich-like structure.
The structure of the apparatus is simpler than the case where the rotating drum 3 and the magnetic attraction member 7 are integrally formed, and the plural magnetic attraction members 7 can be easily provided.

When a plurality of disks 40 are arranged in parallel to the flow direction of the flow path 1 in the right and left direction, as shown in FIG. 6, by arranging the same magnetic poles of the magnet body 7a to face each other, the lines of magnetic force M are curved. Since the magnetic field reaches the entire flow path 1a to every corner and the entire curved flow path 1a, the magnetic adsorption of the activated sludge B can be performed effectively.

Although the above embodiment has been described with reference to the example of the rotary drum 3 having one or two magnetic attraction members 7, as shown in FIG. 8, the rotary drums including the flow paths are coaxially arranged in parallel. By arranging many or two or more in one flow path along the flow direction, the sludge separation treatment capacity can be greatly increased in a short time.

Further, in the above-described embodiment, the columnar magnet body is embedded in the magnetic attraction member and arranged. However, the shape of the magnet body may be any shape, and the whole magnetic attraction member may be a magnet body. Of course.

[0041]

In summary, according to the present invention, the outer periphery of the rotary drum and the magnetic attraction member form a flow path partitioned in an arc shape along the magnetic attraction member. Therefore,
Activated sludge is effectively adsorbed on the magnetic adsorption member because the magnetic force of the magnetic adsorption member that separates the flow passage reliably acts on the activated sludge liquid by flowing the activated sludge liquid containing magnetic powder into the flow channel. can do. The activated sludge adsorbed on the magnetic adsorption member is continuously separated and collected from the magnetic adsorption member by the scraping member provided on the upper portion of the rotary drum as the rotary drum rotates. Further, this magnetic attraction member is formed by a flange or a disk of a rotating drum, and a plurality of magnet bodies are arranged along the circumferential direction such that respective magnetic poles are located on the left and right flow path sides, The magnetic forces of the individual magnets act on the flow path all over, and all the magnetic forces of the magnets can be used effectively.

[Brief description of the drawings]

FIG. 1 is a partially broken side view showing one embodiment of the present invention.

FIG. 2 is a plan view showing one embodiment of the present invention.

FIG. 3 is a view as seen in the direction of arrows DD in FIG. 1;

FIG. 4 is a partially enlarged view of FIG.

FIG. 5 is a diagram showing an example in which the rotary drum of FIG. 4 is modified.

FIG. 6 is a diagram showing an example in which the embodiment of FIG. 5 is modified.

FIG. 7 is a diagram showing an example of the disc in FIG. 5;

FIG. 8 is a bird's-eye view showing an example of a sewage treatment process.

FIG. 9 is an explanatory view showing a conventional magnetic separation device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flow path 1a Curved flow path 3 Rotating drum 7 Magnetic attraction member 7a Magnet 7b Flange 8 Scrape member 40 Disk 50 Drum plate A Activated sludge liquid B Activated sludge C Treated water

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C02F 3/12 C02F 11/12 C02F 1/48 B03C 1/00

Claims (5)

(57) [Claims] 1. A part of a rotary drum having a magnet is made to face and rotates in a flow path in which an activated sludge liquid to which magnetic powder is added flows, and the activated sludge is magnetically adsorbed by the magnet to cause activated sludge and treated water to flow. In the magnetic separation apparatus for activated sludge for separation and recovery, a curved flow path is formed below the rotary drum to cover a lower outer circumference and side surfaces of the rotary drum, and the flow path is formed on an outer circumference of the rotary drum. Characterized in that a flange-shaped magnetic adsorbing member for partitioning the activated sludge is provided on the rotating drum, and a scraping member for removing the activated sludge adsorbed on the magnetic adsorbing member is provided on the rotating drum. Separation device. 2. The magnetic attraction member according to claim 1, wherein a plurality of magnets are arranged along a circumferential direction of a flange formed on an outer periphery of the rotary drum such that respective magnetic poles are located on the left and right flow path sides. 2. The activated sludge magnetic separation apparatus according to claim 1, wherein: 3. The activated sludge magnetic separation apparatus according to claim 1, wherein the rotary drum comprises a disk having the magnet body on an outer peripheral portion, and a drum plate supporting both sides of the disk. 4. A plurality of magnets are provided along an outer peripheral portion of the disk along a circumferential direction so that the magnetic pole faces are located on the disk surface, and the polarity of each magnet body is the same on the disk surface. The magnetic separation apparatus for activated sludge according to claim 3, wherein the apparatus is provided so as to provide: 5. A plurality of disks, both sides of which are supported by the drum plate, the flow path is divided into a plurality of parts by the magnetic suction members on the outer periphery of the disks, and the magnetic suction members opposing each other with the separated flow paths interposed therebetween. 4. The activated sludge magnetic separation apparatus according to claim 3, wherein the magnetic poles of the members are provided so as to have different polarities.