JPH07275620A - Filter - Google Patents

Abstract

PURPOSE:To wash a filter medium efficiently in a short time when it is clogged. CONSTITUTION:An assembly of long crimped filaments 3 as a filter medium 2 is placed in a filter cylinder main body 1. The medium 2 is bonded with a vertically movable filter medium-pressing plate 4 and a fixed supporting plate 5, both plates are arranged to face each other so that the medium 2 is vertically supported, the medium 2 is constituted to be pressed and stretched by the vertical movement of the filter medium pressing plate 4, and the filaments 3 can be maintained in a stretched state during washing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter device for removing solid particles (colloidal particles) suspended in a liquid such as water, and an aggregate of crimped long fiber yarns. The present invention relates to a filtering device used for a filter material (filter).

[0002]

2. Description of the Related Art Conventionally, as a filtering device for filtering solid particles in a liquid such as water,
For example, there is known a filtration device using a sheet material, which is a so-called filter cloth made of a knitted fabric, a non-woven fabric made of fibers formed by binding innumerable fibers, as a filter material.

In the filtering process by such a filtering device,
Gradually, solid particles and the like adhere to the fibers that are the filter medium, and the gaps between the fibers that form the filter medium become clogged (poor porosity), and the filtration efficiency decreases. for that reason,
Generally, when the pressure on the supply side of a liquid to be filtered (hereinafter, referred to as a liquid to be treated) exceeds a certain level, or after a certain period of time, cleaning is performed by a backflow process of the cleaning liquid and reused. Is being done.

In recent years, as a filtering device equipped with a fiber filter material, it is possible to efficiently wash the fiber filter material.
Using a non-twisted yarn aggregate of long fiber crimped yarn as a filter medium,
It has been proposed that this filter medium is arranged in a filter cylinder body so that it can be compressed, and that it is maintained in a compressed state during a filtration process and released during a cleaning process (for example, Japanese Patent Publication No.
42048).

In the proposed filtering device, a filter material made of long fiber yarn is connected to a mounting plate arranged in the upper part of the filter cylinder main body, and during the filtering process, the mounting plate is lowered to the lower part thereof. The filter medium is compressed between it and the supporting plate arranged to form a filter layer, and during the cleaning process, the compression of the filter medium is released by raising the mounting plate, and the filter medium is suspended and washed by backwash of the cleaning liquid. Is to do. In the above, it is possible to move the lower support plate up and down to compress the filter medium.

However, since the filter medium made of the long fiber yarn is only connected to the upper mounting plate,
Even when the compression is released by the lifting of the mounting plate in the cleaning process, the long fiber threads constituting the filter medium have a tendency to compress,
In addition, the fibers are entangled with each other, and the fibers are hung without being sufficiently stretched.

Therefore, even if the cleaning liquid is backwashed, the adhered substances such as solid particles adhering to the filter medium are less likely to be removed than those inside the filter medium, and the pasty substance is not removed and remains. Since it is easy, a large amount of cleaning liquid is required to completely remove the adhered particles, and there is a problem that the cleaning processing time is long.

Further, in the filtration treatment by the above-mentioned filtration device, the filtration gap between the fibers is closed due to the adhesion of solid particles and the like, and the porosity of the filtration medium is gradually reduced. The load increases, the filtration effect at a constant pressure set at the beginning of the filtration process cannot be maintained, and the treatment efficiency also decreases.

Conventionally, when the supply pressure of the liquid to be treated reaches a constant pressure or every fixed time, the cleaning treatment is carried out as described above, and the treatment is performed while keeping the filtering effect substantially constant. The efficiency was not maintained, and the time from one cleaning to the next was shortened accordingly, resulting in a low operating rate.

The present invention has been made in view of the problems in the filtering device using the long fiber yarn as a filter material as described above. The first object of the present invention is to obtain solid particles filtered and the like. It is intended to provide a filtering device capable of efficiently and surely cleaning a small amount of cleaning liquid in a short time when the filter material adheres to cause clogging.

A second object of the present invention is to keep the pressure substantially constant when the load on the filter medium by the liquid to be treated increases due to a decrease in the porosity of the filter medium due to the adhesion of solid particles during the filtration process. An object of the present invention is to provide a filtering device which is controlled so as to be maintained within a range of effective filtration pressure so that the filtering effect can be maintained substantially constant and filtration can be continued and the time from one cleaning to the next cleaning can be lengthened. Is.

[0012]

The present invention is to solve the above-mentioned problems, and the invention of claim 1 is a filtering device for filtering solid particles and the like suspended in a liquid, In the main body of the filter cylinder, the aggregate of long fiber yarns is used as a filter medium and is connected to a vertically movable filter medium pressing plate and a fixed support plate which are vertically supported, and the filter medium is appropriately driven by a driving means. It is characterized in that it can be compressed and expanded by the lifting action of the pressing plate.

According to the filtering apparatus of the present invention, during the filtering process, the filter medium pressing plate which can be moved up and down by the driving means is moved to the side of the fixed supporting plate which faces the filtering medium pressing plate, and the long fibers connected and supported by both plates are supported. A filter material made of thread is compressed with a predetermined pressing force, and thus the liquid to be treated is supplied into the main body of the filter cylinder, and the solid particles suspended in the liquid are filtered by passing through the layer of the compressed filter material. However, the filtered liquid passes through the layer of the filter medium and is discharged from the opposite side.

In the cleaning process of the filter medium, the filter medium pressing plate is moved away from the fixed support plate by the driving means to release the compression of the filter medium in the opposite manner to the above, and the cleaning process is performed, for example, by the reverse flow of the cleaning liquid. At this time, since the filter material made of long fiber threads is connected to the fixed support plate and the filter material pressing plate and is supported vertically, even if the long fiber thread has a compression tendency or the fibers are entangled with each other, By the movement of the filter medium pressing plate, it is forcibly pulled up and down to be held in a sufficiently stretched state.

Therefore, the adhered substances such as the solid particles adhered to the filter medium are easily removed by the backflow of the cleaning liquid,
Paste-like adherent substances can be easily removed, and a small amount of cleaning liquid can be used for efficient cleaning in a short time.

A second aspect of the present invention is a filtration device for filtering solid particles or the like suspended in a liquid, wherein a long fiber yarn aggregate is used as a filter medium in a filter cylinder main body and is vertically opposed to each other. In a filtering device configured to be supported by being connected to at least an upper plate body of the vertically movable filter material pressing plate and the fixed support plate, and the filter material can be compressed by a filter material pressing plate that is vertically moved by appropriate driving means, A pressure sensor for detecting the supply pressure of the liquid to be treated that reaches the filter medium is provided, and the drive means of the filter medium pressing plate is provided so that an arbitrary pressing force can be applied to the filter medium, and the pressure value detected by the pressure sensor is preset. When the set value of the set effective filtration pressure range is reached, the pressure sensor is configured to operate in the direction of relieving the pressure on the filter medium until the detected pressure value decreases to the initial supply pressure. Characterized in that it comprises.

In the filtration device of the present invention, as the filtration progresses, solid particles and the like adhere to the filter medium to close the filter gaps between the fibers and gradually reduce the porosity of the filter layer. The load on the filter medium due to the liquid to be treated increases,
The supply pressure of the liquid to be treated rises.

The increase in the supply pressure of the liquid to be treated is detected by the pressure sensor, and when the detected pressure value reaches the preset value of the effective filtration pressure range set in advance, the driving means of the filter medium pressing plate causes the filter medium to be pressed. It acts in a direction to relieve the pressure on the filter medium to slightly loosen the compression of the filter medium to restore the flowability of the liquid to be treated, whereby the load by the liquid to be treated is reduced and the supply pressure is lowered. The operation of the drive means is continued until the pressure value detected by the pressure sensor drops to the initial supply pressure.

Therefore, the supply pressure of the liquid to be treated is controlled so as to be maintained within the preset effective filtration pressure range, and the filtration treatment is continued within this pressure range, during which time it is substantially constant. The filtration treatment can be performed while maintaining the filtration effect of, and the time from one washing to the next can be lengthened.

When the filtering process further progresses to reach the limit of the filtering action of the filter medium, the cleaning process is performed by the backflow of the cleaning solution as described above.

[0021]

Embodiments of the present invention will now be described with reference to the drawings.

FIGS. 1 and 2 show the outline of one embodiment of the filtration device of the present invention. In the drawings, (1) shows the main body of a filtration cylinder having a circular or polygonal cross section, such as a cylinder or a prism. Is.

(2) is a filter medium composed of a tow-shaped aggregate of long fiber threads (3) provided inside the filter cylinder body (1). As shown in the figure, the filter medium (2) comprises a filter medium pressing plate (4) and a fixed support plate (5) which are vertically arranged to face each other in a filter cylinder main body (1), and a long fiber which is a filter medium. An assembly of threads (3) is connected and supported vertically, and is compressed between the lower fixed support plate (5) as shown in FIG. 2 by the lowering of the upper filter medium pressing plate (4), It is provided so as to form a filtration layer.

The filter medium pressing plate (4) arranged on the upper side in the filter cylinder body (1) is connected to the ascending / descending driving means (7) by an ascending / descending support shaft (6). By the operation of the drive means (7), the filter medium (2) is provided so as to be able to move up and down in a compression direction and an expansion direction.

The elevating and lowering drive means (7) can utilize a cylinder mechanism such as a hydraulic cylinder for hydraulic pressure or a pneumatic cylinder, or screw drive by a motor. In either case, the filter medium at the time of compressing the filter medium can be used. The compression rate of the filter medium (2) can be arbitrarily set by adjusting the pressing force applied to (2).

The filter medium pressing plate (4) and the fixed support plate (5) are perforated plates or grid plates having liquid flow holes (4a) and (5a), and other liquid flowable plate members. Consists of.

The aggregate of long fiber threads (3) constituting the filter medium (2) may be supported by directly connecting the upper and lower ends thereof to the filter medium pressing plate (4) and the fixed support plate (5). I can, but
In the case of the illustrated embodiment, cylindrical mounting seats (8) and (9) are attached to the central portions of the facing surfaces of the both plates (4) and (5) by means of bolt fastening means or the like, and the mounting seats (8) are attached. The cross-shaped or lattice-shaped locking portion inside the opening end of (9) is connected by a binding means such as a rope. And this cylindrical mounting seat (8)
Liquid circulation holes (4a) and (5a) are provided in the inner part of (9).

With this structure, when the filter medium (2) is compressed by the filter medium pressing plate (4) during the filtration process,
As shown in FIG. 2, the filter medium (2) is compressed outside the mounting seats (8) and (9), and the liquid to be treated is filtered by the mounting seats (8) and (9). Since it is possible to reliably flow through the layer of the filter medium (2) from the central part of (1), a good filtration effect can be maintained.

That is, the aggregate of the long fiber threads (3) constituting the filter medium (2) is directly connected to the filter medium pressing plate (4) and the fixed support plate (5), and the liquid flow hole portion (4a) ( 5a)
When the plate is also provided on the periphery of the plate, the liquid circulation hole (4
The liquid to be treated which has passed through a) (5a) may flow around the periphery of the filter medium (2) and may not be sufficiently filtered. However, when it is formed as described above, the liquid to be treated is a filter medium. It is possible to reliably flow between the fibers of (2) to ensure the filtering action. Either one of the filter medium pressing plate (4) and the fixed support plate (5), especially the side of the plate (fixed support plate in the case of the illustrated embodiment) located on the supply side of the liquid to be treated is configured as described above. In this case, the same effect as described above can be exerted.

As the long fiber threads (3) constituting the above-mentioned filter medium (2), polyester fiber, polypropylene,
A multi-filament yarn of synthetic fibers such as polyamide, which is a non-twisted yarn (several tens to several hundreds of single filaments) obtained by crimping single filament fibers to 50 denier or less, preferably 20 denier or less. It is preferably used.

In addition to the above, it is also possible to use a twisted yarn of an ultrafine long fiber yarn having a tens of denier or less obtained by twisting a single yarn fiber of a few denier or less, or a non-crimped long fiber yarn. However, from the viewpoint of the cleaning effect by the backflow treatment, the untwisted yarn of the long fiber yarn is preferable, and in the untwisted yarn of the non-crimped yarn, the filtration gap between the fibers is linear, and the expected filtering effect is obtained. The long-fiber yarn that has been crimped as described above is suitable because it cannot be crimped.

The long fiber threads (3) are used as a tow-shaped aggregate of a large number and are used in an amount necessary for a filtering action. The amount, the number, the length, etc. of the long fiber threads (3) are the filter medium (2) at the time of compression. So that the thickness of the filter can be at least 50 mm, preferably 100 mm or more, the diameter of the filter cylinder body (1) and the filter medium pressing plate (4)
It may be set in accordance with the maximum distance between the fixed support plate (5) and the like.

For example, the diameter of the filter cylinder body (1) is 300 m.
In the case of m, untwisted long filament yarn of 700 denier / 60 filament is wound in a ring shape into a tow-shaped aggregate, and both ends of the rope (3a) (3b) made of a synthetic resin such as polypropylene. ) And tie it to the mounting seats (4a) and (5a).

Reference numeral (10) is a supply pipe for the liquid to be treated which is opened in the filtration cylinder body (1), (11) is a valve provided in the supply pipe (10), and (12) is for taking out the filtered liquid. The pipe (13) is a valve provided in the take-out pipe (12). A cleaning liquid supply pipe (14) is provided in the take-out pipe (12).
Are connected via a valve (15), and a cleaning liquid discharge pipe (16) is connected to the treatment liquid supply pipe (10) by the valve (1).
It is connected through 7). (18) is a drainage pipe.

Therefore, the valve (11) of the supply pipe (10) for the liquid to be treated and the valve (13) of the filtered liquid take-out pipe (12) are closed, and the supply pipe (14) and the discharge pipe (16) for the cleaning liquid are provided. By opening the valves (15) (17) of
The cleaning liquid is configured to flow in the main body of the filter cylinder (1) against the flow of the liquid to be treated at the time of filtration for cleaning.
Each of these valves is usually configured to open and close by a signal from the control unit, for example.

The supply pipe (10) for the liquid to be treated is provided with a pressure sensor (20) for detecting the supply pressure of the liquid to be treated reaching the filter medium (2). The pressure value detected by is input to the control unit (30) and the operation of the drive means (7) of the filter medium pressing plate (4) is controlled, so that the supply pressure of the liquid to be treated can be controlled. There is.

That is, the control unit (30) compares the pressure value detected by the pressure sensor (20) with a preset value of the effective filtration pressure range, and the detected pressure value reaches the preset value. At this time, in response to a signal from the control unit (30), the driving means (7) operates in such a direction as to alleviate the pressure on the filter medium (2) and loosen the compression of the filter medium (2), and the pressure sensor (20). The operation is continued until the detected pressure value falls to the initial supply pressure of the liquid to be treated (when the supply pressure is reached, the operation is stopped).

Further, the operation by the driving means (7) is repeated, and the distance of the filter medium pressing plate (4) from the fixed supporting plate (5) becomes a certain value or more, and the compression relaxation limit of the filter medium (2) is reached. When the range, that is, the limit range of the filtering action is reached, the valves (11) and (13) are closed and the valves (15) and (17) are opened by a signal from the control unit (30) to perform the cleaning process by the backflow of the cleaning liquid. Is configured to take place.

The filtering process and the cleaning process by the above filtering device will be described.

During the filtration process, the driving means (7) for raising and lowering
The filter press plate (4) is lowered to the side of the lower fixed support plate (5) which is arranged opposite to the filter press plate (4), and is composed of long fiber yarns (3) connected between both plates and supported in the vertical direction. The filter medium (2) is compressed with a predetermined pressing force according to the purpose of filtration.

Thus, the valve (11) of the supply pipe (10) for the liquid to be treated and the valve (13) of the pipe for taking out the filtrate (13) are opened to supply the liquid to be treated into the main body (1) of the filtration cylinder. Then, a filtering process is carried out by passing through the filter material (2).
The liquid to be treated supplied to the main body of the filter cylinder (1) surely flows between the fibers of the filter medium (2) through the liquid flow hole (5a) of the fixed support plate (5) and the cylindrical mounting seat (9). During that time, solid particles and the like in the liquid to be treated are filtered, and the filtered liquid is discharged from the take-out pipe (12) on the opposite side.

When the filter medium (2) is washed, the filter medium pressing plate (4) is moved upward by the driving means (7) in the opposite direction to release the compression of the filter medium (2). Washing is performed by back-flowing a washing liquid such as water. At this time, in particular, the long fiber yarn (3) which is the filter medium (2) vertically supported by being connected to the filter medium pressing plate (4) and the fixed support plate (5). ), Even if there is a compression habit or the fibers are entangled with each other, it is positively stretched in the vertical direction against it.

Therefore, in combination with the backflow action of the cleaning liquid, the entanglement of the fibers can be prevented, and even if the long fiber yarn (3) is a crimped yarn, the solid particle adhering substance can be reliably washed off to the inside, and particularly The paste-like adherent substance is also easily peeled off, and it can be efficiently removed and washed, and a sufficient washing effect can be obtained with a small amount of washing liquid and in a short time.

Further, in the above-mentioned filtration treatment, solid particles and the like adhere to the filter medium (2) composed of the long fiber threads (3), and the porosity of the filter medium (2) gradually decreases with the degree of the adherence.
The load due to the flow of the liquid to be treated on the filter material (2) increases, and the filtration effect cannot be maintained constant.

Then, as the load on the filter medium (2) increases, the supply pressure of the liquid to be treated in the filter cylinder body (1) gradually rises, and this pressure is used as the pressure sensor (20).
To control the compression density of the filter medium (2).

This control operation will be described with reference to FIGS. 3 and 4.

In the initial stage of the filtration process, the filter medium (2)
Is in the state of FIG. 3 (a) as it is pressed by the lowering of the filter medium pressing plate (4) by the driving means (7). At this time, the drive means (7) applies a constant pressing force (F0) set according to the liquid to be filtered, the purpose of filtration, etc., and the filter medium (2) obtains a predetermined filtering effect. The compression density (D0) is such that

In this way, the liquid to be treated is supplied to the filter cylinder body (1) at a predetermined supply pressure (P0) and passes through the filter medium (2) to perform filtration, and the supply pressure of the liquid to be treated is measured by the pressure sensor. Detected by (20), the following control is performed as shown in FIG.

That is, first, in step 1, the pressure value (Px) detected by the pressure sensor (20) is set to the control unit (3).
0) is compared with the set value (P1) set as the limit pressure of the effective filtration pressure range in advance, and when the detected pressure value (Px) is smaller than the set value (P1), the detected pressure value (Px) is maintained while continuing the filtration. ) And the set value (P1) are repeated, and when the detected pressure value (Px) is larger than the set value (P1), the process proceeds to the next step 2.

In step 2, the drive means (7) is actuated to raise the filter medium pressing plate (4) in a direction to alleviate the compression of the filter medium (2). Along with this, the volume of the filter medium (2) becomes large and the compression density (D1) becomes small, so that the flowability of the liquid is restored and the load by the liquid to be treated is reduced, and the detected pressure value (Px) on the supply side. Gradually decreases.

Then, in the next step 3, it is judged whether or not the pressure (F1) by the relaxed driving means (7) is within the control limit region of the compression relaxation of the filter medium (2), that is, the limit region of the filtering action. If it has not reached the range (Fmax), the process proceeds to step 4.

In step 4, the drive means (7) continues to operate until the pressure value (Px) detected by the pressure sensor (20) becomes the same as the initial supply pressure (P0) until the same. If so, the operation of the driving means (7) is stopped, the process returns to step 1, and the same operation as above is repeated to continue the filtering process.

If the pressure applied by the driving means (7) reaches the limit region (Pmax) of the filtration action ((b) of FIG. 3), the supply of the liquid to be treated is stopped and the driving means (7) is stopped. ) To release the compression of the long fiber threads (3) constituting the filter medium (2), and a washing liquid such as water is caused to flow backward from the filtrate extraction pipe (12) side for washing.

As described above, by changing the compression density of the filter medium (2) in accordance with the supply pressure of the liquid to be treated, the filtration effective pressure initially set is reached until the above-mentioned filtering action limit range is reached. The filtration can be continued within the range, and the filtration treatment can be continuously performed while keeping the filtration effect substantially constant, and moreover, the time from one washing to the next washing becomes longer,
The operating rate and processing efficiency of the filtration device can be improved.

Regarding the above-mentioned control mechanism, the filter medium (2) made of long fiber yarns (3) is connected to both the filter medium pressing plate (4) and the fixed support plate (5) arranged above and below. The filter device is not limited to a vertically supported structure, and, for example, a filter material pressing plate (4), which is an attachment plate disposed on the upper side, is connected to the filter material to support it in a suspended state, and a lower fixed support plate ( Also in the case of a filter device that is provided between the filter element and the filter element 5), the supply pressure of the liquid to be treated is detected by the pressure sensor as described above, and the drive means operates according to the detected pressure value to operate the filter medium. It can be implemented in the same manner by being configured to adjust and control the compression density.

Further, in the above-mentioned embodiment, the case where the liquid to be treated is circulated from the lower part to the upper part of the filter cylinder main body (1) has been shown. On the contrary, the filter cylinder main body (1) is circulated. It is also possible to arrange a supply pipe for the liquid to be treated in the upper part of the pipe and a pipe for taking out the liquid to be filtrated in the lower part so that the liquid to be treated is circulated from the top to the bottom to pass the filter medium. Also, the same filtering treatment and washing treatment as those in the above-described examples can be performed.

Further, as for the filter medium pressing plate (4) and the fixed support plate (5) for supporting the filter medium (2), contrary to the above-described embodiment, the fixed support plate is provided on the upper side of the filter tube main body (1). It is also possible to dispose a filter medium pressing plate that can be moved up and down by a driving means on the lower side, and to provide a filter medium that is supported by being connected between both plates so that it can be compressed and expanded.
The same filtering and washing processes as described above can be carried out, and the same operational effects are obtained.

[0058]

As described above, according to the filtering device of the present invention, the filter material made of long fiber yarn is connected to the vertically movable filter material pressing plate and the fixed supporting plate and supported vertically. Since the filter material is provided so as to be compressible and expandable by raising and lowering the filter material pressing plate, the long-fiber yarns constituting the filter material are stretched against the compression habit or the like during the cleaning process, so Since it can be washed by backflow etc., it can relatively easily and reliably remove adherent substances with a sticky stickiness, and it also makes it possible to reduce the amount of washing liquid and wash in a short time. Can be greatly improved.

When the pressure of the liquid to be treated is detected by the pressure sensor and the compression density of the filter medium can be automatically controlled by the detected pressure value as in the second aspect of the present invention, a predetermined value is obtained. The filtration can be continued within the effective filtration range of
Therefore, the filtration effect can be continuously maintained for a long time while keeping the filtration effect substantially constant, and thus the time from one cleaning to the next can be extended, the number of times of cleaning is small, the operating rate of the filtering device, and the efficiency of the filtering process. Can be increased.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention before compression of a filter medium.

FIG. 2 is a vertical cross-sectional view of part of the above filter medium when compressed.

FIG. 3 is a schematic explanatory diagram showing the control state of the compression density correction of the filter medium at the initial stage (a) of the filtration process and after the compression density correction (b).

FIG. 4 is a flowchart of the control mechanism of the above.

[Explanation of symbols]

 (1) Filter cylinder body (2) Filter medium (3) Long fiber yarn (4) Filter medium pressing plate (5) Fixed support plate (6) Shaft (7) Elevating drive means (8) (9) Mounting seat (20) ) Pressure sensor (30) Control unit

Claims (2)

[Claims] 1. A filter device for filtering solid particles or the like suspended in a liquid, wherein a filter material is an assembly of long fiber threads in a filter cylinder body, which is vertically movable and is capable of moving up and down. A filter device, comprising: a plate and a fixed support plate, which are vertically supported so that the filter medium can be compressed and expanded by an elevating action of a filter medium pressing plate by an appropriate driving means. 2. A filter device for filtering solid particles or the like suspended in a liquid, wherein a filter material is an aggregate of long fiber threads as a filter material, and a vertically movable filter material pressing member is disposed inside the filter cylinder body. In a filtering device configured to be supported by being connected to at least an upper plate member of a plate and a fixed support plate, and the filter medium can be compressed by a filter medium pressing plate that is appropriately moved up and down by driving means, a liquid to be treated reaching a filter medium layer A pressure sensor for detecting the supply pressure of the filter medium, the driving means of the filter medium pressing plate is provided so that an arbitrary pressure can be applied to the filter medium, and the pressure detected by the pressure sensor has a preset effective filtration pressure. When the set value of the range is reached, the pressure sensor detects the pressure value and reduces the pressure to the initial supply pressure. Filtration device.