JPH01151960A - Centrifugal separator - Google Patents

Abstract

PURPOSE:To mechanically dislodge residual solid matters from a filter to recover them, by providing a filter press member at the end of a push rod mounted on a basket and a rod driving means which comes into contact with the push rod to force it toward the inner side of the basket. CONSTITUTION:After a scraping process is completed, a driving means 32 is moved forward from a retreated position to be brought into contact with a push rod 30, causing the rod 30 to be forced into a basket 8 so that a filter press member 31 at the end of the push rod 30 pushes a part of a filter 25 inwardly in a radial direction of a basket 8. In this manner, a crack is caused in a layer of a solid matters S (cakes or crystals) around the part of the filter 26 which has been pushed out, whereby the solid matters S are broken and dislodged from the filter 25. Consequently, by dislodging and recovering the residual solid matters in a basket 8, the waste quantity of solid matters can be decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a centrifugal separator that removes liquid through permeation holes provided in the peripheral wall of a basket.

[Prior Art] In a centrifugal separator that removes liquid through permeation holes provided in the peripheral wall of a basket, the basket is rotated at high speed to remove the liquid, and then the inside of the basket is rotated at low speed while the liquid is removed. The step of scraping off the solids is carried out by inserting a scraping blade into the solids (cake or crystals) formed around the periphery.

In this case, a filter (>T
If the scraping blade comes into contact with the surface of the cloth (cloth or net), the filter will be damaged.
It is possible to enter only up to this position. Therefore,
5 to 10 am on the inner circumference of the basket (inner circumference of the filter)
A solid layer with a thickness of 100 mL will remain, and if the next step is to remove liquid from the raw solution as it is, it will not be possible to remove the liquid successfully because the filter function has deteriorated.

Conventionally, the remaining solids were removed by spraying high-pressure water toward the solids layer remaining on the inner periphery of the basket to wash away the solids after performing a scraping process using a scraping blade.

[Problems to be Solved by the Invention] In conventional centrifuges, solids remaining on the inner periphery of the basket are washed away with high-pressure water after the solids are scraped off. The solid matter (product) formed through the treatment has to be re-slurried and discarded, which is wasteful and uneconomical.

In addition, instead of using high-pressure water, it is possible to remove the residual solids from the filter by blowing compressed air onto the residual solids, but in this case, the effect of removing the solids is low, and the solids are There was a problem in that there was a lot of loss due to scattering.

An object of the present invention is to provide a centrifugal separator equipped with a rotatably supported basket having a large number of permeation holes in its peripheral wall, and a filter disposed on the inner surface of the basket, without using high pressure water or compressed air. The purpose is to enable solid matter to be peeled off from the inner surface of the filter.

[Means for Solving the Problems] Therefore, in the present invention, a plurality of push rods are arranged at intervals in the circumferential direction of the basket so that each push rod can penetrate the peripheral wall of the basket and be displaced in the radial direction. A filter pressing member interposed between the filter and the peripheral wall of the basket is provided at the tip of each push rod supported and positioned within the basket. A rod driving means is provided that contacts the push rod and drives the push rod toward the inside of the basket, so that the drive means can displace the push rod toward the inside of the basket. The rod driving means is provided so that it can be retracted to a position where it does not come into contact with the push rod, so that the driving means does not interfere with the rotation of the basket during the liquid removal process.

[Operation of the invention] As described above, when a push rod is attached to the basket and a filter pressing member is provided at the tip of the push rod, the push rod can be driven toward the inside of the basket rack 1- by the rod driving means. After the scraping process is completed, the push rod is driven to displace the filter pressing member toward the inner diameter of the basket, thereby pushing a part of the filter toward the inner diameter of the basket at the portion where the filter pressing member is provided. I can put it out. When the filter is extruded in this manner, the remaining solid layer around the extruded portion of the filter is cracked and loses its shape, and the distorted solids peel off and fall off the filter. Therefore, by appropriately setting the number of push rods and pressing members, the solids remaining in the basket can be dropped off and collected, and the amount of wasted solids can be reduced.

Since the rod driving means is provided so as to be retracted to a position where it does not come into contact with the push rod, the basket can be rotated without any problem during normal liquid removal processing.

[Example] The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows the overall configuration of an embodiment of the present invention.
In the figure, reference numeral 1 denotes a casing supported by at least three supporting devices 2 equipped with shock absorbers. The casing 1 is formed into a cylindrical shape with a bottom, and its upper end opening is closed by a removable lid plate 3. A bearing 4 is disposed at the center of the bottom of the casing 1, and a rotating shaft 5 that extends vertically inside the casing 1 is supported by the bearing 4. A pulley 6 is attached to the lower end of the rotating shaft 5,
The pulley is connected via a belt 7 to a rotary drive device (not shown), such as a hydraulic motor, supported on the underside of the casing 1.

Reference numeral 8 denotes a basket housed in the casing 1, and the basket 8 includes a cylindrical peripheral wall (mesh plate) 9, an annular end wall 10 protruding radially inward from the upper end of the peripheral wall 9, and a bottom wall 11. and a boss portion 12 provided at the center of the bottom wall 11, and the boss portion 12 is fitted onto and supported by the rotating shaft 5. An annular recess 13 concentrically surrounding the boss 12 is formed near the center of the bottom wall 11 of the basket 8.

This recess consists of a flat bottom 14 and an inclined wall 15 rising obliquely upward from the outer peripheral edge of the bottom 14, and the upper end of the inclined wall 15 is continuous with the inner peripheral edge of the horizontal part of the bottom wall 11. . A large number of permeation holes 16 are formed in the peripheral wall 9, and the liquid separated by rotation of the basket is diffused to the outside through the permeation holes 16.

An annular liquid guiding member 17 having an angular cross section is welded to the lower inner surface of the peripheral wall of the casing 1, and a drain 018 is provided near the lower end of the peripheral wall of the casing 1.

The liquid guide member 17 is inclined so as to be lowest near the liquid drain port 18, so that the liquid discharged from the basket 8 is guided to the liquid drain port 18 by the liquid guide member 17.

A liquid supply pipe 20 is inserted into the basket by penetrating the lid plate 3 of the casing 1, and the stock solution to be treated is supplied into the basket 8 from the jet hole 20a of this liquid supply pipe.

The scraping device 21 rotatably and slidably penetrates the cover plate 3.
A drive shaft 22 is provided, and a scraping blade 23 is attached to the lower end of the drive shaft 22 inserted into the basket. The drive shaft 22 is connected to a drive device (not shown), and the drive device performs an operation of advancing the scraping blade 23 into the peripheral wall 9 side of the basket 8 and an operation of lowering the scraping blade 23 to the bottom side of the basket 8. It is now possible to

Also, a solid matter discharge pipe 24 passes through the lid plate 3 and enters the basket.
is inserted, and the lower end opening of the solid matter discharge pipe 24 is in the recess 1.
3. Solid matter discharge pipe 24
is connected to a suction pump (not shown), and the solid matter discharge pipe 2
4 allows the solid matter accumulated in the recess 13 to be sucked and discharged.

A filter 25 is arranged inside the basket 8. This filter 25 consists of an endless cylindrical part 26 along the inner surface of the peripheral wall 9 of the basket, and annular parts 27 and 28 joined to both ends of the cylindrical part 26.
28 are arranged respectively along the inner surface of the end wall 10 and the inner surface of the bottom wall 11 of the basket. A ring-shaped filter fixing member is attached to the inner periphery of the annular parts 27 and 28, and the fixing member is attached to the inner periphery of the end wall 10 of the basket 8 and the inner periphery of the horizontal part of the bottom wall 11. It is bolted.

The filter 25 used in the present invention may be made of a deformable material, but it is preferable to use a cloth (so-called oven cloth) as the filter.

The configuration of each part described above is already known. The present invention
In this type of centrifugal separator, a push rod 30;
It is characterized in that it includes a filter suppressing member 31 attached to the tip of the push rod 30 and interposed between the peripheral wall 9 of the basket and the filter 25, and a rond driving means 32 for driving the push rod 30.

A plurality of push rods 30 are provided and arranged at intervals in the circumferential direction of the basket, and each push rod passes through the peripheral wall 9 of the basket and is supported so as to be displaceable in the radial direction.

In this embodiment, eight push rods 30 are provided as shown in FIG. 2, and these push rods are arranged at equal intervals in the circumferential direction of the basket. As shown in FIG. 3, each push rod 30 has its tip inserted into the basket through a hole 33 provided through the peripheral wall of the basket, and is supported by a bearing 34 attached to the outer surface of the peripheral wall 9 of the basket 8. Supported in a slidable manner. The filter pressing member 31 is made of a disc-shaped member, and each push rod 3 located inside the basket 8
It is attached to the tip of the basket with its plate surface perpendicular to the radial direction of the basket.

In this embodiment, a recess 36 into which the filter pressing member 31 fits is provided on the inner surface of the peripheral wall 9 of the basket 8, and the filter pressing member 31 is inserted into the basket when the push rod 30 is fully retracted toward the outer diameter side of the basket. It is housed in the recess 36 and does not protrude from the inner surface of the peripheral wall 9. A disc-shaped bushing plate 37 is fixed to the rear end of the push rod 30 located outside the basket.

The rod driving means 32 consists of a piston rod attached to a piston 39 of an air cylinder 38 attached to the peripheral wall of the casing 1. In the example shown in FIG. 2, four cylinders 38 are attached to the peripheral wall of the casing 1 at angular intervals of 90 degrees, and a disc-shaped contact plate 40 is attached to the tip of each piston rond (zero-rad drive means 32). is installed. Each piston rod (rod driving means 32) is provided at the same height position so as to be aligned with the push rod 30, and when each rod driving means 32 is aligned with any push rod 30, the rod drive When air is supplied from the boat 38a of the air cylinder 38 provided with the means, the abutting plate 40 comes into contact with the bushing plate 37 to displace the push rod toward the inner diameter side of the basket 8.

As shown in FIG. 3, the rod driving means 32 is provided so that it can be retracted to a position where it does not come into contact with the bushing plate 37 of the push rod 30. 8 can be rotated without any trouble.

An encoder rotor 41 is attached to the lower end of the rotating shaft 5 adjacent to the pulley 6, and a stator 42 of the encoder is attached to the bottom of the casing 1. This encoder rotates the stator 42 every time the basket rotates a predetermined angle.
is a well-known device that generates a pulse signal, and in this example,
The stator 42 generates a pulse signal at a position a certain angle (the angle required to stop the basket) before the position where each rod driving means 32 is aligned with each push rod 30.

In this embodiment, a basket rotation control device is provided which controls the rotation of the basket using the output pulses of this encoder as input. This control device rotates the basket at a low speed when a drive command is given, and gives a stop command to the rotational drive source of the basket when the stator 42 of the encoder generates a pulse. This stops the basket and causes the four rod drive means 32 to move every other (
(see FIG. 2).

In this embodiment, a cylinder control device for controlling the air cylinder 38 is also provided. This control device controls the boat 3 of the air cylinder 38 when it is confirmed that the basket has stopped.
8b is opened to supply compressed air to the boat 38a, and the piston 39 is displaced toward the basket 8 side. This brings the rod driving means 32 into contact with the push rod 30, causing the push rod to enter the basket. After a certain period of time has elapsed, the boat 38a of the air cylinder 38 is opened to supply compressed air to the boat 38b, the piston 39 is moved back, and the rod driving means 32 is retracted. After that, a drive command is given to the basket rotation control device to rotate the basket at a low speed.

Next, the operation of this embodiment will be explained. First, the basket 8 is rotated at high speed to supply the stock solution into the basket from the liquid supply vibrator 20, and then a liquid removal process is performed for a certain period of time. Through this liquid removal step, the solids and liquid in the raw solution are separated, and a solid layer is formed on the inner periphery of the basket 8.

After the liquid removal process is completed, a cleaning liquid is supplied into the basket from the liquid supply pipe 20 to wash the solid matter.

After the basket is rotated at high speed for a certain period of time to perform dehydration, the basket is decelerated and a solid matter scraping process is performed.

In this scraping step, the scraping blade 23 is moved into the solid matter layer and is displaced downward to scrape off the solid matter and drop it into the recess 13 at the bottom of the basket. Then, the inside of the solid matter discharge pipe 24 is evacuated by a suction pump, and the solid matter in the recess 13 is discharged through the solid matter discharge pipe 24.

After the scraping process is completed, the basket is stopped.

At this time, the inner circumference of the filter 25 in the basket has 5 to 10
A solid layer with a thickness of approximately mm+ remains. Therefore, in the present invention, the basket is stopped at a position where each rod driving means 32 is aligned with the push rod 30, and the push rod 30 is pushed into the basket by the rod driving means 32, and the filter pressing member 31 is moved toward the inner diameter side of the basket. extrude At this time, the filter 25 is pushed out toward the inner diameter side of the basket 8 as shown in FIG. 4, so that the shape of the residual solid matter S attached to the inner periphery of the filter is broken and the solid matter is peeled off from the filter. and fall to the bottom side of the basket.

In this embodiment, four air cylinders are provided,
A rod driving means 32 is driven by each cylinder. In this case, the four air cylinders may be driven at the same time, but the four air cylinders may also be driven individually in a determined order to make it easier to drop solid matter attached to the inner periphery of the filter. .

Alternatively, only one air cylinder 38 and one O-rad drive means 32 may be provided, and the rotation of the basket may be controlled so as to sequentially align each push rod with the rod drive means.

After the solid matter remaining on the inner periphery of the filter is dropped into the recess 13 as described above, the solid matter is discharged through the solid matter discharge pipe 24. After that, when the basket is rotated at medium or high speed with the metal rod driving means 32 retracted, the push rod 30 is pushed out by centrifugal force and returns to its original position, and the filter 25 is also rotated around the inner circumference of the basket by centrifugal force. Return to normal position along with. After that, the inside of the basket is washed, and the process moves on to the next undiluted solution.

In the above embodiment, the piston rod of the air cylinder 38 was used as the rod driving means 32, but as shown in FIG. It can also be used as In this case, the cam follower 46 is attached to the rear end of the push rod 30, and the cam follower 46 is attached to the cam 45 by rotating the basket 8 at a low speed while the piston rod of the air cylinder is extended. Push the push rod 30 into the basket. In the illustrated example, a return spring 47 is provided that returns the push rod 30 to the position where it protrudes outside the basket.
This spring can also be omitted. After the solids are removed from the filter, the piston rod of the air cylinder is moved back to a position where the cam 45 does not come into contact with the cam follower 46.

In the above explanation, an air cylinder is used as the drive source for driving the rod drive means, but this cylinder may also be a hydraulic cylinder, or an electric drive source such as a plunger type electromagnet may be used as the drive source for the rod drive means. Good too.

In some cases, the rod driving means may be operated manually.

In the above embodiment, the rotating shaft of the basket is supported on the bottom side of the casing, but the present invention can also be applied to a centrifugal separator having a structure in which the rotating shaft is supported on the lid side (ceiling side) of the casing. Can be done.

Further, in the above embodiment, the solids in the basket are discharged through the solids discharge pipe, but in the present invention, the means for discharging the solids from the basket is arbitrary.
For example, the present invention can be applied to a centrifugal separator that has an opening for discharging solid matter at the bottom side of a basket and discharges the solid matter from the opening.

In the above embodiment, eight push rods were provided, but the number of push rods is arbitrary. Appropriate modifications can be made to the arrangement of the push rods, the support structure, and the shape of the filter pressing member provided at the tip of each push rod, but in this case care must be taken not to upset the weight balance of the basket. Of course.

[Effects of the Invention] As described above, according to the present invention, a push rod is attached to a basket, a filter pressing member is provided at the tip of the push rod, and the push rod is driven toward the inside of the basket by the rod driving means. I tried to get it, so
After the scraping process is completed, the push rod is driven to displace the filter pressing member toward the inner diameter of the basket, thereby pushing out a part of the filter toward the inner diameter of the basket at the portion where the filter pressing member is provided. It is possible,
This allows the residual solid layer around the extruded portion of the filter to lose its shape and be peeled off from the filter. Therefore, the solid matter remaining in the basket can be dropped off and recovered, and there is an advantage that the width of the solid matter that is wasted can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of an embodiment of the present invention, Fig. 2 is a sectional view taken along the l-1f line in Fig. 1, Fig. 3 is an enlarged sectional view showing main parts of the embodiment, and Fig. 4 is the same FIG. 5 is a cross-sectional view of the main part showing a state in which the push rod is pushed into the basket in the embodiment, and FIG. 5 is a cross-sectional view of the main part showing a modification of the mechanism for driving the push rod. DESCRIPTION OF SYMBOLS 1... Casing, 8... Basket, 9... Peripheral wall part, 25... Filter, 30... Push rod, 31... Filter pressing member, 32... Rod driving means, 38... ··Air cylinder. Figure 1

Claims (1)

[Scope of Claims] A centrifugal separator comprising a rotatably supported basket having a large number of permeation holes in a peripheral wall, and a filter disposed on the inner surface of the basket, the filter being arranged at intervals in the circumferential direction of the basket. a plurality of push rods disposed and supported so as to be radially displaceable through the peripheral wall of the basket; and a plurality of push rods provided at the tips of each push rod located within the basket between the filter and the peripheral wall of the basket. and a rod driving means that contacts the push rod and drives the push rod toward the inside of the basket, and the rod drive means is retracted to a position where it does not contact the push rod. A centrifugal separator characterized in that it is provided so as to be able to