JP2007105585A - Filter apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter apparatus capable of enhancing the filtration concentration performance and the SS collection ratio. <P>SOLUTION: This filter apparatus comprises cylindrical or conical inner filter medium 1 and outer filter medium 2 disposed concentrically to each other and a spiral partition 3 installed in a filtration space 4 between the inner filter medium 1 and the outer filter medium 2. The spiral partition 3 is not rotated but only the inner filter medium 1 and/or the outer filter medium 2 is rotated around its axis. In this operation step, a treated liquid is fed into the filtration space 4 from a plurality of liquid filling ports formed on its one end, filtrated by passing it through the inner filter medium 1, and filtrate by passing it through the outer filter medium 2. The filtrate liquid is discharged to the outside, and cakes are discharged from the other end of the filtration space 4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a filtration device.

Filter materials such as metal screens, nets, and perforated plates are superior in terms of operability, maintainability, durability, etc. compared to cloth (fiber) materials. There is a pressure filtration device such as a rotary pressure dehydrator. This device has a long history and has a very simple structure, so it features low power, low noise, low cost, etc., and even when applied to a hard-to-dehydrate solid-liquid mixture with a low solid content. Since excellent dewatering performance is obtained, it is often used in the field of sewage sludge dewatering (see, for example, Patent Documents 1 and 2).
However, in a screw press comprising a cylindrical outer filter medium and a screw inserted therein, the liquid to be treated is transferred from the inlet side to the outlet side at a low speed, and at the same time, generated by the tightening force of the screw. Although it is continuously dehydrated by the pressing pressure, since the filtrate is squeezed out only from the outer filter medium, it is difficult to shorten the length of the outer filter medium, and it is difficult to downsize the equipment.
On the other hand, in the rotary pressurization type dehydrator, it is necessary to increase the diameter of the disk or to arrange a plurality of dehydrators in order to improve the throughput of dehydration filtration. It was.
Therefore, in view of such problems, the present inventors provide a concentrically arranged cylindrical or conical inner filter medium and outer filter medium, and a filtration space between these inner filter medium and outer filter medium. A spiral partition, which feeds the liquid to be treated from one end of the filtration space, discharges the cake from the other end of the filtration space, and passes through the inner and outer filter media. Is a filtration device configured to discharge the outside of the filter, and the inner filter medium and / or the outer filter medium rotate around the axis, and the spiral partition is configured not to rotate (for example, Patent Document 3). ).
JP 2001-212697 A JP 2001-113109 A Japanese Patent Application No. 2005-176901

In the above invention, the apparatus itself can be miniaturized and the dehydration performance can be improved. However, since the number of places to which the liquid to be treated is fed is one or two, the cake concentration in the transport direction in the flow path is Further, there is a possibility that the filtration differential pressure distribution is generated and the filtration concentration performance at a place away from the inlet is lowered.
Furthermore, depending on the viscosity of the solid content, an input pressure higher than the filtration differential pressure is required to ensure fluidity in the flow path, and excessive pressure causes the solid content to flow out of the filter medium and the recovery rate decreases. There was also a fear of doing.
Then, the main subject of this invention is providing the filtration apparatus which improves filtration concentration performance and SS collection | recovery rate.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
The invention according to claim 1 is a concentrically disposed cylindrical or conical inner filter medium and outer filter medium, and a spiral partition provided in a filtration space between the inner filter medium and the outer filter medium. The liquid to be treated is fed from one end of the filtration space, the cake is discharged from the other end of the filtration space, and the filtrate that has passed through the inner and outer filter media is discharged to the outside. A filtration apparatus configured to perform the above process, in which the inner filter medium and / or the outer filter medium rotate around an axial center, and the spiral partition does not rotate, and the liquid to be treated is fed into the liquid to be treated. However, it is the filtration apparatus characterized by having formed in multiple places communicating with the said filtration space.

(Function and effect)
By performing filtration and concentration with two surfaces of the inner filter medium and the outer filter medium, it is possible to reduce the size of the equipment as compared with a screw press that performs filtration only with a conventional outer filter medium. In addition, the inner filter medium and / or the outer filter medium rotate around the axis and the spiral partition does not rotate, so that the liquid to be treated fed into the filtration space is spirally installed along the partition. While moving inside, first, filtration and concentration by the two sides of the inner and outer filter media is performed, and then press dewatering is performed, but not only the inner and outer filter media but also the ribbon screw, all of which are configured to be freely rotatable compared to the screw press The filtration device according to the present invention can simplify the structure, reduce the manufacturing cost, and improve the maintainability.
Then, the treatment liquid inlets for feeding the treatment liquid are formed at a plurality of locations in communication with the filtration space, so that the concentration and pressure distribution of the treatment liquid immediately after entering the filtration space are made uniform. And the filtration concentration performance can be improved. In addition, it is not necessary to apply excessive pressure in consideration of pressure loss, compared to the case where the liquid inlets to be processed are formed at one or two locations, and the SS recovery rate is prevented by preventing the outflow of solids from the filter medium. (%) Can be improved, and an extra burden is not applied to the filtration device. Furthermore, since the length of the flow path through which the liquid to be treated is conveyed can be substantially shortened, the pressure loss is reduced, contributing to the improvement of the SS recovery rate (%).

<Invention of Claim 2>
The invention according to claim 2 is a concentrically arranged cylindrical or conical inner filter medium and outer filter medium, and a spiral partition provided in a filtration space between the inner filter medium and the outer filter medium. The liquid to be treated is fed from one end of the filtration space, the cake is discharged from the other end of the filtration space, and the filtrate that has passed through the inner and outer filter media is discharged to the outside. The inner filter medium and / or the outer filter medium rotate around an axis, and the spiral partition does not rotate, and the partition is a filter that feeds a liquid to be treated. The filtration apparatus is provided with a space away from one end side of the space, and a storage space for storing the liquid to be treated is formed between one end side of the partition and one end side of the filtration space.

(Function and effect)
The partition is provided separately from one end side of the filtration space into which the liquid to be processed is fed, and a storage space for storing the liquid to be processed is formed between one end side of the partition and one end side of the filtration space. Accordingly, it is possible to further promote the uniformization of the concentration and pressure distribution of the liquid to be treated.

<Invention of Claim 3>
A cylindrical or conical inner and outer filter media arranged concentrically;
A spiral partition provided in a filtration space between the inner filter medium and the outer filter medium,
Filtration configured to send the liquid to be treated from one end of the filtration space, discharge the cake from the other end of the filtration space, and discharge the filtrate that has passed through the inner and outer filter media to the outside. A device,
The inner filter medium and / or the outer filter medium rotate around an axis, and the spiral partition is configured not to rotate,
A liquid inlet for receiving liquid to be processed is formed on a side surface of the inner filter medium and / or the outer filter medium.
A filtration device characterized by that.

(Function and effect)
Since the liquid inlet for processing is formed on the side surface of the inner filter medium and / or the outer filter medium, the liquid inlet is also rotated if the inner filter medium and / or the outer filter medium is rotated in the circumferential direction, Since the liquid to be processed is fed while the liquid to be processed is stirred in the filtration space, the concentration and pressure distribution of the liquid to be processed can be made more uniform.

<Invention of Claim 4>
Invention of Claim 4 is a filtration apparatus of Claim 2 or 3 with which the to-be-processed liquid inlet port which sends in a to-be-processed liquid was formed in multiple places communicating with the said filtration space.

(Function and effect)
By forming a plurality of treatment liquid inlets through which the liquid to be treated is communicated with the filtration space, it is possible to further promote the uniformization of the concentration and pressure distribution of the liquid to be treated. In addition, it is not necessary to apply excessive pressure in consideration of pressure loss, compared to the case where the liquid inlets to be processed are formed at one or two locations, and the SS recovery rate is prevented by preventing the outflow of solids from the filter medium. (%) Can be improved, and an extra burden is not applied to the filtration device. Furthermore, since the length of the flow path through which the liquid to be treated is conveyed can be substantially shortened, the pressure loss is reduced, contributing to the improvement of the SS recovery rate (%).

<Invention of Claim 5>
According to a fifth aspect of the present invention, at least the inner peripheral edge and the outer peripheral edge of the spiral partition on the inlet side of the liquid to be processed are close to or in contact with the inner filter medium and the outer filter medium, respectively. It is a filtration device given in any 1 paragraph.

(Function and effect)
Since the liquid to be processed sent into the filtration space has a low cake concentration and fluidity, filtration and concentration are caused by the inner and outer filter media in the vicinity of the inlet side of the liquid to be processed. Therefore, in the vicinity of the inlet side of the liquid to be processed, filtration and concentration by solid-liquid separation is an important function, but at least the inner peripheral edge and the outer peripheral edge on the inlet side of the liquid to be processed are respectively connected to the inner side of the spiral partition. By setting it as the structure which adjoins or contacts a filter medium and an outer side filter medium, the cake adhering to the filtration surface of a filter medium is scraped off, and the efficiency of filtration concentration can be maintained. In addition, the fed liquid to be processed can be spirally moved along the partition.

<Invention of Claim 6>
A sixth aspect of the present invention is the filtration device according to any one of the first to fifth aspects, wherein the rotation speed of the inner filter medium and the rotation speed of the outer filter medium are rotatable with a speed difference.

(Function and effect)
When the rotation speed of the inner filter medium and the rotation speed of the outer filter medium rotate with a speed difference, a shearing force is generated in the cake moving in the filtration space. Therefore, for example, for a liquid to be treated containing raw sludge having a high fiber content or mixed raw sludge, the dewatering efficiency can be improved by this shearing force. In addition, when the relative speed of each of the inner and outer filter media is large, the cake in the vicinity of the rapidly rotating filtration surface (for example, the filtration surface of the inner filter media) moves to the other filtration surface (for example, the filtration surface of the outer filter media). The effect appears and the mixing action in the cake occurs, so that the moisture content distribution in the filtration device can be made uniform.

<Invention of Claim 7>
According to a seventh aspect of the present invention, the inner filter medium is provided with a first rotation drive means, and the outer filter medium is provided with a second rotation drive means. The first rotation drive means and the second rotation drive means. The filtration device according to any one of claims 1 to 6, wherein the filtration device is a rotation driving means different from the means.

(Function and effect)
It is possible to improve the dewatering efficiency by applying shear force to the cake due to the difference in rotation speed between the inner and outer filter media, but this effect depends on the properties of the target cake. It is necessary to set the speed difference between the inside and outside. In the present invention, the difference in speed between the inside and outside can be easily adjusted in accordance with the cake properties by using a rotation driving means different from the first rotation driving means and the second rotation driving means.

<Invention of Claim 8>
The invention according to claim 8 is configured so that the pitch interval of the spiral partition is shortened from the one end side to the other end side. The filtration device according to item.

(Function and effect)
The spiral partition is configured so that the pitch interval becomes shorter as it goes from one end side to the other end side of the filtration space, thereby narrowing the discharge path of the cake and enhancing the squeezing effect, thereby discharging the cake It is possible to eliminate the unevenness (distribution) of the moisture content of the water and make it uniform.

<Invention of Claim 9>
The invention according to claim 9 is configured such that the axial center is vertically oriented, the entire apparatus is vertically oriented, and the liquid to be treated is fed in a pressurized state from below to above. The filtration device according to any one of 1 to 8.

(Function and effect)
Depending on the properties of the cake, the degree of progress of dehydration and the design of the filter chamber volume may not be balanced, and the cake filling rate may decrease. In this case, in the configuration in which the filtration device is arranged sideways (horizontal type), the filtrate is affected by gravity and leaches into a cake having a low filling rate, so that the moisture content of the discharged cake is increased. is there. Accordingly, the axial center is vertically oriented, the entire apparatus is vertically oriented, and the liquid to be treated is fed upward using gravity by being configured so that the liquid to be treated is fed in a pressurized state from below to above. It is possible to prevent the cake from being leached to the cake discharge side, and therefore, it is possible to eliminate unevenness (distribution) of the moisture content of the discharged cake and make it more uniform.

<Invention of Claim 10>
A tenth aspect of the present invention is the filtration device according to any one of the first to ninth aspects, wherein the axial center is laterally oriented and the entire device is laterally disposed.

  According to the present invention, advantages such as the ability to improve filtration concentration performance and SS recovery rate are brought about.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
<Configuration of filtration device according to the present invention>
As shown in FIG. 1 and FIG. 2, an inner cylinder rotating shaft to which a driving force is transmitted by a first rotation driving means (not shown) such as a motor is disposed inside the casing 7 in the filtration device according to the present invention. 5, a rotatable cylindrical inner filter medium 1 having an upper plate 1A connected thereto, a rotatable cylindrical outer filter medium 2 disposed concentrically with the inner filter medium 1, an upper plate 7A of the casing 7 and Both ends are fixed to the bottom plate 7B, and a spiral (ribbon screw) partition 3 disposed in a filtration space 4 formed between the inner filter medium 1 and the outer filter medium 2 is provided. In addition, although the casing 7 is a cylindrical shape in this Embodiment, it is not restricted to this, Shapes, such as a polyhedron, may be sufficient.

  As shown in FIG. 2, to-be-processed liquid inlets 10, 10,... Are formed on the bottom plate 7 </ b> B of the casing 7 where the filtration space 4 is projected. To be treated is fed. By forming a plurality of liquid inlets to be processed, the concentration and pressure distribution of the liquid to be processed immediately after being introduced into the filtration space 4 can be made uniform, and the filtration space is mainly subjected to filtration and concentration by solid-liquid separation. 4 The filtration concentration performance at the bottom is improved. In addition, by forming a plurality of liquid inlets to be processed, it is not necessary to apply excessive pressure in consideration of pressure loss, compared to the case where liquid inlets to be processed are formed at one or two places. The SS recovery rate (%) can be improved by preventing the solids from flowing out of the filter, and an extra burden is not applied to the filtration device. Furthermore, since the length of the flow path through which the liquid to be treated is conveyed can be substantially shortened, the pressure loss is reduced, contributing to the improvement of the SS recovery rate (%).

  The liquid to be treated is pumped by a pump (not shown), and rises from the bottom to the top of the casing 7 together with this pressure by friction caused by the rotation of the inner filter medium 1 and the outer filter medium 2. When the entire center of the apparatus is placed sideways with the axis of the apparatus itself in the horizontal direction, the liquid to be treated moves within the apparatus only by the frictional force generated by the rotation of the inner filter medium 1 and the outer filter medium 2 without pumping. You may let them. Moreover, although the to-be-processed liquid inlet 10,10, ... is four places in this Embodiment, it should just be formed in multiple places (preferably 3 places or more, more preferably 4 places or more) without being restricted to this. .

  Here, the form shown in FIG. 10 can also be proposed as another form of the liquid inlet to be treated. In this embodiment, a liquid supply pipe 11 to be processed is connected to the central portion of the casing 7, and a tip portion thereof penetrates the side surface of the inner filter medium 1 to form a liquid supply inlet 11 </ b> A. The liquid feed pipe 11 to be treated is configured to rotate in accordance with the rotation of the inner filter medium 1, and the liquid feed inlet 11 </ b> A formed on the side surface of the inner filter medium 1 also rotates while being filtered. The liquid to be treated is fed into the tank. Since the liquid to be treated 11A formed on the side surface of the inner filter medium 1 feeds the liquid to be treated while rotating in the circumferential direction, the liquid to be treated is easily stirred in the filtration space 4, and the liquid to be treated The concentration / pressure distribution can be made more uniform. Although this process liquid inlet 11A is one place in FIG. 10, it is not restricted to this but can be attached in multiple places. In addition, a part of filtrate which solid-liquid separation was made | formed among process liquids is discharged | emitted from the filtrate discharge port 12 formed in the baseplate 7B of the casing 7, as FIG. 10 shows.

  Further, the liquid inlet 11 </ b> A to be treated is not limited to the side surface of the inner filter medium 1, and although not shown, it may be formed on the side surface of the outer filter medium 2, or formed on each side surface of the inner filter medium 1 and the outer filter medium 2. May be.

  On the side surface (outer peripheral surface) of the inner filter medium 1, a wedge wire is stretched as a filter medium, and the slits of the wedge wire are arranged along the rotation axis. Of the liquid to be treated that is fed into the filtration space 4 formed between the inner filter medium 1 and the outer filter medium 2, a part of the filtrate that has undergone solid-liquid separation is transferred to the bottom plate 7 </ b> B of the casing 7 in the inner filter medium 1. It is accumulated and finally discharged from the filtrate outlet 12.

  The outer filter medium 2 has a structure in which the upper end of the outer periphery is suspended from the upper plate 7A of the casing 7 by a rail and a roller guided by the rail, and the side surface of the upper end is not shown. The outer filter medium 2 itself is connected to an outer rotation shaft (not shown) to which a driving force is transmitted by a second rotation driving means (not shown) such as a motor via a pinion gear (not shown). It is designed to rotate. Further, similarly to the inner filter medium 1, a wedge wire is stretched as a filter medium on the inner peripheral surface of the outer filter medium 2. The slits of this wedge wire are arranged along the rotational axis, and of the liquid to be treated that is fed into the filtration space 4, a part of the filtrate that has undergone solid-liquid separation is formed between the casing 7 and the outer filter medium 2. It is stored in the bottom plate 7B in the middle portion and finally discharged from the filtrate discharge port 13.

  Here, even when the inner filter medium 1 and the outer filter medium 2 are rotated at the same angular velocity (° / sec), the peripheral speed (mm / sec) of each radial difference is generated, so that shear force is generated in the cake. Thus, dewatering efficiency is improved. For example, for the liquid to be treated containing raw sludge having a high fiber content or mixed raw sludge, since this shear force is more effective, a slight speed difference is given to the inner filter medium 1 and the outer filter medium 2, By rotating it, it is possible to further improve the dehydration efficiency. Moreover, when the relative speed of the inner side filter medium 1 and the outer side filter medium 2 is large, the cake in the vicinity of the filtration surface (for example, the filtration surface of the inner filter medium 1) that rotates rapidly is the other filtration surface (for example, filtration of the outer filter medium 2). The effect of migrating to the surface) side appears, and the mixing action in the cake occurs, so that the moisture content distribution in the filtration device can be made uniform.

  As described above, the shearing force is applied to the cake due to the difference in angular velocity between the filtration surfaces of the inner and outer filter media 1 and 2, and the dewatering efficiency is improved. However, this effect depends on the properties of the target cake, so that it operates in an optimum state. In this case, it is desirable to set the speed difference between the inside and outside according to the cake properties. For this reason, in this embodiment, the inner and outer filter media 1, 2 are provided with rotational drive means such as individual motors so that the speed difference can be easily adjusted.

  On the other hand, depending on the cake properties, when a shearing force is applied, the cake may be fluidized, and conversely, the dewaterability may be impaired. In such a case, it is preferable to rotate the cake at a constant speed difference. In addition, for cakes that have a dehydration effect due to shearing force and the cake properties hardly change throughout the year, they may be rotated at a constant speed difference. May be rotated at the same speed by a single motor.

  The inner filter medium 1 and the outer filter medium 2 do not necessarily need to be rotated, and only one of them may be rotated.

  The filter medium used for the inner and outer filter media 1 and 2 is not limited to the wedge wire, and a punched plate (not shown), a wire mesh (not shown), a filter cloth (not shown), or the like can be used. . In addition, a wedge wire with a high opening ratio of the filtration surface at the lower part of the filtration space 4 where solid-liquid separation is main, and a contact area with the cake is high at the upper part of the filtration space 4 where compression dehydration is main (low opening ratio). A punched plate may be arranged.

  As shown in FIGS. 1 and 4, the partition 3 has a spiral shape (ribbon screw shape), and is disposed in an annular filtration space 4 formed between the inner filter medium 1 and the outer filter medium 2. . Since the partition 3 is fixed to the upper plate 7A and the bottom plate 7B of the casing 7, the partition 3 does not rotate around the axis. As a result, the filtration device according to the present invention can simplify the structure, reduce the manufacturing cost, and improve the maintainability, compared to a screw press that can rotate not only the inner and outer filter media but also the ribbon screw. Can be achieved.

  The inner peripheral edge and the outer peripheral edge of the partition 3 are configured to be close to or in contact with the filtration surfaces of the inner filter medium 1 and the outer filter medium 2, respectively. With this configuration, cake attached to the filtration surfaces of the inner and outer filter media 1 and 2 can be easily scraped, and the efficiency of filtration and concentration can be maintained. The liquid to be processed can be spirally raised along the partition 3. The lower part of the filtration space 4, that is, the vicinity of the treated liquid inlets 10, 10,..., Is mainly concentrated by filtration through solid-liquid separation, so that the inner edge and the outer edge of the partition 3 are at least treated. It suffices if the vicinity of the liquid inlets 10, 10,... Is close to or in contact with the inner and outer filter media 1, 2, respectively.

  Further, as shown in FIG. 4, by attaching a scraper 16 formed of rubber or the like to the inner and outer peripheral edges of the partition 3, the inner filter medium 1 and the outer filter medium 2 rotate around the axis, and the partition 3 rotates. Due to the non-configuration, the cake captured on the filtration surface can be scraped off by the scraper 16. Note that, as described above, the lower part of the filtration space 4, that is, the vicinity of the processing liquid inlets 10, 10,... It is sufficient that a scraper is attached in the vicinity of the 10, 10,.

  The partition 3 may have a uniform spiral pitch throughout the filtration space 4, but in order to eliminate the unevenness (distribution) of the moisture content of the cake discharged, as shown in FIG. 1 and FIG. It is preferable to configure the partition 3 so that the pitch interval becomes shorter as it goes from the bottom plate 7B side of the casing 7 to the upper plate 7A side. Specifically, in the upper portion of the filtration space 4, the spiral pitch It is preferable to shorten the discharge path of the cake and shorten the cake discharge path to enhance the squeezing effect. On the other hand, as shown in FIGS. 5 to 8 to be described later, when the radius difference between the inner and outer filter media 1 and 2 is narrowed in order to improve the dewatering efficiency in the upper part of the filtration space 4, the spiral partition 3 is connected to the casing. 7 may be configured such that the pitch interval increases from the bottom plate 7B side to the upper plate 7A side.

  Although not shown, a hole through which the cake can pass can be formed in a part of the spiral blade to promote stirring and mixing of the cake. Further, as shown in FIG. 9, the lower part of the partition 3 is provided apart from the bottom plate 7B of the casing 7 in the lower part of the filtration space 4, that is, in the vicinity of the liquid inlets 10, 10,. An annular space (storage space 17) surrounded by the inner filter medium 1 and the outer filter medium 2 can be formed by cutting the lower part. The storage space 17 functions as a space for storing the liquid to be processed. It is possible to promote the homogenization of the concentration and pressure distribution of the liquid to be processed by the configuration in which the liquid to be processed is fed from the processing liquid inlets 10, 10,. In particular, by adopting it together with the liquid inlet 10A having the form shown in FIG. 10, it is possible to further promote the homogenization of the concentration / pressure distribution. In this case, the partition 3 and the bottom plate 7B of the casing 7 may be fixed via, for example, an arbitrary connecting member (supporting member) such as the pillars 18 and 18.

  As shown in FIGS. 1 and 4, the scraper 16 is provided in the axial direction of the inner filter medium 1 and the outer filter medium 2 in the casing 7 and on the inner and outer peripheral edges of the partition 3 so as to be close to or in contact with the filtration surface. Along each of them, both end portions are attached and fixed to the upper plate 7A and the bottom plate 7B of the casing 7. In FIG. 4, one scraper 16 is attached to each of the inner peripheral edge and the outer peripheral edge, but the scraper 16 may be attached to a plurality of locations. Moreover, as a modification, the scraper 16 may be attached only to the lower part of the filtration space 4 where solid-liquid separation is main. As a mounting method in this case, although not shown, it may be installed only on the bottom plate 7B of the casing 7, or may be installed so as to connect the bottom plate 7B of the casing 7 and the partition 3, or in the axial direction. You may install so that the periphery of the adjacent partition 3 may be bridged and connected. In addition, the scraper 16 is not attached in parallel to the axial direction but is not shown, but the scraper 16 may be attached to the respective leading ends along the inner and outer peripheral edges of the partition 3.

  As described above, the scraper itself may be made of rubber, resin, or the like that can be pressed against the filtration surface by elastic force. However, as a modification, a spring is attached to the tip of the scraper. A blade having a function of making the blade movable in the radial direction of the inner filter medium 1 and the outer filter medium 2 by using a spring or the like can be used.

  Here, the relationship with the inner side filter medium 1, the outer side filter medium 2, and the partition 3 is demonstrated. The liquid to be processed fed from the liquid inlets 10, 10,... Formed on the bottom plate 7 </ b> B of the casing 7, which will be described later, has a low cake concentration and fluidity. Filtration concentration occurs through the openings of the cylindrical filter media in the inner filter media 1 and the outer filter media 2. In the lower part of the filtration space 4, filtration concentration by solid-liquid separation action is an important function. However, when the filtration concentration progresses to some extent, the concentrated cake adheres to the filtration surface and the filtration efficiency decreases. Therefore, in order to maintain the concentration efficiency, the scraper 16 is attached to the partition 3, and the surface of the filter medium in the inner filter medium 1 and the outer filter medium 2 is scraped frequently, thereby scraping the cake adhered to the surface.

  Moreover, since the cake which lost fluidity | liquidity by the concentration effect | action produces a frictional force with a filter medium, it is conveyed by the rotating filter medium in the circumferential direction of the inner and outer filter media 1,2. However, a spiral (ribbon screw-shaped) partition 3 is arranged in the filtration space 4, and the cake rotating along the inner and outer filter media 1 and 2 interferes with the partition 3, thereby centering the axis. And move in the axial direction. By this movement, the cake is finally discharged from the cake discharge port 14 formed in the upper part of the filtration space 4 while being filtered and concentrated. In addition, although mentioned later, the back pressure plate 15 which suppresses discharge | emission of a cake is attached to the cake discharge port 14, and a cake is consolidated in the filtration space 4 by forcibly suppressing discharge | emission amount, The moisture content can be reduced.

  Although the filtration space 4 which concerns on embodiment has shown the cyclic | annular thing which has the same cross-sectional area from the top to the bottom, the lower part of the filtration space 4 has a large-capacity filtration chamber volume in order to ensure a processing amount. On the other hand, in order to improve the dewatering efficiency in the upper part of the filtration space 4, it is preferable to narrow the radius difference between the inner and outer filter media 1,2. Specifically, as shown in FIG. 5, the shape of the outer filter medium 2 remains the same, and the radial direction of the inner filter medium 1 from the liquid feed inlets 10, 10,... It is possible to propose a shape that expands continuously (substantially conical shape) or a shape that expands stepwise as shown in FIG. 6 (multi-stage cylindrical shape). Further, as shown in FIG. 7, the shape of the inner filter medium 1 remains the same, and the radial direction of the outer filter medium 2 is continuously directed from the liquid feed inlets 10, 10... To the cake outlet 14 side. It is also possible to propose a shape that shrinks in a step-like manner, or a shape that shrinks in a staircase shape as shown in FIG.

  As shown in FIGS. 1 and 2, the inner cleaning pipe 8 is provided along the inner peripheral surface of the inner filter medium 1, and a plurality of cleaning nozzles 8 </ b> A, 8 </ b> A,. The inner cleaning tube 8 is attached so as to face the peripheral surface. Similarly, the outer cleaning pipe 9 is provided along the outer peripheral surface of the outer filter medium 2, and the outer cleaning pipe 9A, 9A,... It is attached to the tube 9. Then, while rotating the inner filter medium 1 and the outer filter medium 2 around the axis, the cleaning water is jetted from the plurality of cleaning nozzles 8A, 8A,..., 9A, 9A,. 2 filtration surface is washed. The washing water sprayed at the time of washing is stored as washing wastewater on the bottom plate 7B of the casing 7 in the inner filter medium 1 and the bottom plate 7B between the casing 7 and the outer filter medium 2 together with the filtrate. The filtrate is discharged from the filtrate outlets 12 and 13.

  Here, the inner and outer filter media 1 and 2 are sprayed with a high-pressure cleaning liquid, but it is preferable that the cleaning is performed by spraying an alkaline chemical as the cleaning liquid. In addition, it is more preferable to install an ultrasonic transmitter on the filtration surfaces of the inner and outer filter media 1 and 2 to vibrate and clean the filter media themselves, since the cleaning power is improved.

  In addition, the installation positions of the inner and outer cleaning pipes 8 and 9 and the cleaning nozzles 8A and 9A are not limited to the above, and are installed in the filtration space 4, and a cleaning nozzle (not shown) is attached to the partition 3 and the like, so that the filtration space The cleaning liquid may be sprayed from within 4. Further, a plurality of inner and outer cleaning tubes 8 and 9 may be installed. Moreover, in the form shown in FIG. 10, although the inner side washing | cleaning pipe | tube 8 is abbreviate | omitted for convenience, it cannot be overemphasized that you may attach.

  As shown in FIG. 3, the cake discharge port 14 is formed in the part which projected the filtration space 4 in the upper plate 7A of the casing 7, From this, the dehydrated cake is discharged | emitted. A back pressure plate 15 is attached to the cake discharge port 14. The back pressure plate 15 generates discharge resistance, and the amount of sludge discharged is adjusted to further squeeze the cake and lower the moisture content. Thus, the volume can be reduced.

<The filtration method according to the present invention>
The filtration method using the filtration apparatus according to the present invention will be described below.
First, the liquid to be processed is pumped to the liquid inlets 10, 10,..., And the liquid to be processed is fed into the filtration space 4. The liquid to be treated sent into the filtration space 4 is subjected to two-side filtration by the inner filter medium 1 and the outer filter medium 2 while spirally rising along the partition 3. The inner filter medium 1 and the outer filter medium 2 are respectively rotated by first and second rotation driving means (not shown) such as a motor. At this time, if necessary, the inner filter medium 1 and the outer filter medium 2 are rotated in the same direction with a speed difference. The inner filter medium 1 and the outer filter medium 2 do not necessarily need to be rotated, and only one of them may be rotated.

  The liquid to be treated rises along the partition 3 due to the pumping pressure and rotational frictional force, but solid-liquid separation is performed in the lower part of the filtration space 4 between the inner filter medium 1 and the outer filter medium 2, In the upper part, dewatering is performed and finally a cake discharge port 14 is formed, from which the dehydrated cake is discharged.

  By rotating the inner filter medium 1 and the outer filter medium 2 and preventing the partition 3 from rotating, the scraper 16 scrapes off the cake accumulated on the respective filtration surfaces. At this time, as described above, the cleaning surfaces of the clogged inner filter medium 1 and outer filter medium 2 are cleaned by spraying cleaning water from the plurality of cleaning nozzles 8A, 8A,..., 9A, 9A,. The sprayed wash water is stored as wash wastewater on the bottom plate 7B of the casing 7 in the inner filter medium 1 and the bottom plate 7B between the casing 7 and the outer filter medium 2 together with the filtrate. It is discharged from the outlets 12 and 13.

  In the upper part of the filtration space 4, a cake having a high water content after the solid-liquid separation is raised rises. This cake is caused by rotational friction between the inner filter medium 1 and the outer filter medium 2 and discharged by the back pressure plate 15. Squeezing is promoted by the resistance, the moisture content is reduced, the volume is reduced, and the cake is discharged from the cake outlet 14.

It is a longitudinal cross-sectional view of the filtration apparatus which concerns on this invention. It is the II sectional drawing (transverse sectional view). FIG. It is the schematic for demonstrating the relationship between a partition and a scraper. It is a longitudinal cross-sectional view which shows the outline of the other Example of a filtration apparatus. It is a longitudinal cross-sectional view which shows the outline of the other Example of a filtration apparatus. It is a longitudinal cross-sectional view which shows the outline of the other Example of a filtration apparatus. It is a longitudinal cross-sectional view which shows the outline of the other Example of a filtration apparatus. It is the schematic for demonstrating the storage space. It is an Example of another to-be-processed liquid inlet tube.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Inner filter medium, 1A ... Upper plate, 2 ... Outer filter medium, 3 ... Partition, 4 ... Filtration space, 5 ... Inner cylinder rotating shaft, 7 ... Casing, 7A ... Upper plate, 7B ... Bottom plate, 8 ... Inner washing pipe, DESCRIPTION OF SYMBOLS 9 ... Outer washing | cleaning pipe | tube, 10 ... To-be-processed liquid inlet port, 11 ... To-be-processed liquid inlet pipe | tube, 11A ... To-be-processed liquid inlet port, 12 ... Filtrate discharge port, 13 ... Filtrate discharge port, 14 ... Cake discharge port , 15 ... back pressure plate, 16 ... scraper, 17 ... storage space, 18 ... pillar.

Claims (10)

A cylindrical or conical inner and outer filter media arranged concentrically;
A spiral partition provided in a filtration space between the inner filter medium and the outer filter medium,
Filtration configured to send the liquid to be treated from one end of the filtration space, discharge the cake from the other end of the filtration space, and discharge the filtrate that has passed through the inner and outer filter media to the outside. A device,
The inner filter medium and / or the outer filter medium rotate around an axis, and the spiral partition is configured not to rotate,
A liquid inlet for supplying liquid to be processed is formed at a plurality of locations in communication with the filtration space.
A filtration device characterized by that. A cylindrical or conical inner and outer filter media arranged concentrically;
A spiral partition provided in a filtration space between the inner filter medium and the outer filter medium,
Filtration configured to send the liquid to be treated from one end of the filtration space, discharge the cake from the other end of the filtration space, and discharge the filtrate that has passed through the inner and outer filter media to the outside. A device,
The inner filter medium and / or the outer filter medium rotate around an axis, and the spiral partition is configured not to rotate,
The partition is provided apart from one end side of the filtration space for feeding the liquid to be treated,
Between the one end side of this partition and the one end side of the filtration space, a storage space for storing the liquid to be treated was formed.
A filtration device characterized by that. A cylindrical or conical inner and outer filter media arranged concentrically;
A spiral partition provided in a filtration space between the inner filter medium and the outer filter medium,
Filtration configured to send the liquid to be treated from one end of the filtration space, discharge the cake from the other end of the filtration space, and discharge the filtrate that has passed through the inner and outer filter media to the outside. A device,
The inner filter medium and / or the outer filter medium rotate around an axis, and the spiral partition is configured not to rotate,
A liquid inlet for receiving liquid to be processed is formed on a side surface of the inner filter medium and / or the outer filter medium.
A filtration device characterized by that.   The filtration apparatus of Claim 2 or 3 with which the to-be-processed liquid inlet which delivers a to-be-processed liquid was formed in multiple places in communication with the said filtration space.   The filtration device according to any one of claims 1 to 4, wherein at least an inner peripheral edge and an outer peripheral edge of the spiral partition on the inlet side of the liquid to be processed are close to or in contact with the inner filter medium and the outer filter medium, respectively. .   The filtration device according to any one of claims 1 to 5, wherein a rotation speed of the inner filter medium and a rotation speed of the outer filter medium are rotatable with a speed difference.   The inner filter medium is provided with a first rotation drive means, the outer filter medium is provided with a second rotation drive means, and the first rotation drive means and the second rotation drive means are separate from the rotation drive means. The filtration device according to any one of claims 1 to 6, wherein   The filtration device according to any one of claims 1 to 7, wherein the spiral partition is configured such that a pitch interval is shortened from the one end side to the other end side.   9. The apparatus according to claim 1, wherein the shaft center is vertically oriented, the entire apparatus is vertically oriented, and the liquid to be treated is sent in a pressurized state from below to above. The filtration device described.   The filtration device according to any one of claims 1 to 8, wherein the shaft center is horizontally oriented and the entire device is horizontally oriented.

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