WO2001026776A1

WO2001026776A1 - Rotary type compressive filtrating machine

Info

Publication number: WO2001026776A1
Application number: PCT/JP2000/007073
Authority: WO
Inventors: Takaharu Otsuka; Jun Ohashi
Original assignee: Tomoe Engineering Co., Ltd.
Priority date: 1999-10-14
Filing date: 2000-10-12
Publication date: 2001-04-19
Also published as: CN1378478A; CN1199705C; JP3739613B2; KR20020029784A; JP2001113109A; AU7684600A; KR100481628B1

Abstract

A rotary type compressive filtrating machine (1) capable of increasing a dewatering efficiency of a dewatering cake to be discharged, wherein unprocessed stock solution is led continuously into a filtration chamber (10) formed in a rectangular cross-section and extending annularly to rotatingly move a permeable donut-shaped screen (5) continuously in the end direction of the filtration chamber (10) in order to move, while compressing, the stock solution successively in the end direction by a friction between the unprocessed stock solution and the screen (5) in the filtration chamber (10), and a pressurizing plate (13) is provided in the filtration chamber (10) so that the cross-sectional area of the filtration chamber (10) is reduced gradually toward the moving direction of the unprocessed stock solution.

Description

Description: Rotary compression filter

The present invention relates to a compression filter for filtering and compressing a hydrated material (processed undiluted solution) such as a raw material of a processed food or a semi-processed product thereof, or sludge, etc., and in particular, an annular filter formed around a rotation axis. The present invention relates to a rotary compression filter that performs dehydration treatment by gradually applying pressure to a stock solution as it proceeds in a filtration chamber. Background art

There are various types of devices that separate solids and liquids, such as centrifuges, centrifugal filters, filters—presses, screw presses, rotary vacuum filters, and rotary compression filters. Of these, rotary compression filters are described, for example, in the publication of Canadian Patent Application No. 404223 (filing date: June 1, 1998). Structures shown in FIGS. 7 and 8 are known.

FIG. 7 is a partially cutaway perspective view showing the structure of a conventional typical rotary compression filter 101, and FIG. 8 is an AA line of the rotary compression filter 101 of FIG. FIG. As is clear from these figures, this rotary compression filter 101 is basically composed of a rotating shaft 102, an inner ring spacer 103, an outer ring spacer 104, and two sheets. And a donut-shaped screen 105, 105, a partition plate 106, and a back pressure device (not shown), an outer casing, a driving device, and the like.

More specifically, the rotating shaft 102 is held substantially horizontally, and is supplied with a driving force by a driving device (not shown), so that the rotating shaft 102 shown in FIG. It rotates in the direction of arrow B at a low speed (about 0.2 to 1.3 rotations Z). The inner ring spacer 103 is fixed around the rotation axis 102, and rotates in the same direction according to the rotation axis 102.

The outer ring spacer 104 is arranged outside the inner ring spacer 103 and is held by an external casing (not shown). 2 includes a circular portion extending over about 240 ° to 300 ° on the concentric circle, and a linear portion extending in the tangential direction of the concentric circle to the end portion 104b. The outer ring spacer 104 has a circular portion in which the inner peripheral surface 104c is always opposed to the outer peripheral surface 103a of the inner ring spacer 103 at a constant interval. The thickness W 1 of the outer ring spacer 104 in the axial direction of the rotating shaft 102 is equal to the thickness W 2 of the inner ring spacer 103.

The two screens 105 and 105 have inner peripheral portions 105 a and 105 a fixed on both side surfaces of the inner ring spacer 103, respectively, and outer peripheral portions 105 and 105. b, 105 b are arranged in such a position and size as to be in contact with both side surfaces of the outer ring spacer 104. Therefore, the screens 105 and 105 rotate in the same direction according to the inner ring spacer 103 when the rotation shaft 102 rotates, and at this time, the outer peripheral edge 105 b , 105 b slide on both side surfaces of the outer ring spacer 104.

Each of the screens 105 and 105 has a number of small holes of about 0.18 mm in diameter to ensure water permeability, and removes water from the processing stock solution as described later. It acts as a fill for you. The partition plate 106 is held substantially horizontally and in a direction orthogonal to the axial direction of the rotating shaft 102, and the thickness of the partition plate 106 in the axial direction of the rotating shaft 102 is maintained. The dimension W3 matches the thickness dimension W1 of the outer ring spacer 104 and the thickness dimension W2 of the inner ring spacer 103. Also, inside the partition plate 106 The end 106a is formed so as to conform to the curvature of the outer peripheral surface 103a of the inner ring spacer 103, make surface contact with the curvature, and slide.

The end (outside end 106b) of the partition plate 106 opposite to the inside end 106a is the base end 104a and the end 104 of the outer ring spacer 104. It is held at a position with a predetermined interval between b and. The space secured between the outer end portion 106 b and the base end portion 104 a of the outer ring spacer 104 is provided as a stock solution supply port 108, and the untreated solution to be introduced into the apparatus. The space secured between the outer end 106 b and the outer end 104 b of the outer race spacer 104 is used to serve as the cake outlet 109. Has become.

The bottom surface 106 c of the partition plate 106 coincides with the tangential direction of the outer peripheral surface 103 a of the inner ring spacer 103, and the linear portion of the outer ring spacer 104. It extends parallel to the top surface 104d. The rotary compression filter 101 has a structure that is closed by an outer casing, except for a stock solution supply port 108, a cake outlet 109, and a liquid discharge port (not shown).

A back pressure device having a movable valve 107 as shown in FIG. 12 is provided on the side of the cake outlet 109. The movable valve 107 of the back pressure device is formed of a flexible material, and is bent so that the end 107 a on the cake outlet 109 side contacts the inner wall of the outer casing 113 on the opposite side. The opening area of the cake outlet 109 can be freely adjusted from the fully open state shown in (1) of FIG. 12 to the fully closed state shown in (2) of FIG.

Here, the operation method and operating principle of the conventional rotary compression filter 101 having the above-mentioned structure are shown in FIG. 9 (a cross-sectional view of the rotary compression filter 101 of FIG. 7 taken along the line CC). This will be briefly described with reference to FIG. First, at the start of operation, as shown in (2) of Fig. 12, the back pressure With the valve 107 fully closed, the filtration chamber 110 (the inner ring spacers 103 and the partition plate 106, and the outer ring spacers) were fed through the undiluted solution supply port 108 shown in Fig. 9. It is a space with a rectangular cross section (see Fig. 8) formed between it and 104, and it extends linearly with the part (annular part) that extends in an annular shape (C shape). The process solution is introduced into the space from the stock solution supply port 108 to the cake outlet 109 via the annular portion and the straight portion. At this time, since the movable valve 107 of the back pressure device is in the fully closed state as described above, the introduced undiluted solution is not discharged to the outside from the cake outlet 109, and the filtration chamber 110 Of the filtration chamber 110, the entire annular part and part of the straight part are closed on both sides by two opposing screens 105, 105. (Hereinafter, the part of the filtration chamber 110 whose side is blocked by these screens 105, 105 is referred to as “screen part.”) As described above, since a large number of small holes for ensuring water permeability are provided, the water in the processing stock solution is screened during the process of storing the processing stock solution in the filtration chamber 110. Through the small holes, the water is gradually discharged out of the filtration chamber 110. As a result, the processing stock solution becomes a slurry by increasing the solid content concentration, and a part thereof adheres to the screen surface. The water discharged to the outside of the filtration chamber 110 flows down the gap between the inner wall of the outer casing and the screen 105, and is discharged to the outside of the device from the liquid discharge port.

In this state, a driving device (not shown) is driven to supply a driving force to the rotating shaft 102, and the rotating shaft 102 is driven at a low speed (0.2 to 1.3 rotations) in the direction of arrow B shown in FIG. (About Z minutes). Then, the inner ring spacer 103 fixed around the rotation axis 102 and both sides of the inner ring spacer 103 The screen 105 fixed to is rotated in the same direction.

When the screen 105 rotates, the undiluted solution introduced into the filtration chamber 110 is separated from the undiluted solution by the frictional force generated between the rotating screen 105 and the slurry-like undiluted solution. From the supply port 108 to the cake outlet 109, the inside of the filtration chamber 110 is sequentially advanced. As described above, when the slurry-like undiluted solution proceeds in the filtration chamber 110, dehydration further proceeds in the process, and the slurry-like undiluted solution gradually becomes a cake (dehydrated cake). . Then, the frictional force with the screen 105 also increases, and the increased frictional force causes the dehydrated cake to be transported further to the front. However, it is not conveyed at the same speed as the screen 105, and conversely, the preceding dewatered cake is compressed. For this reason, the dehydration of the preceding dehydration cake will further progress.

In this manner, the undiluted solution introduced into the filtration chamber 110 undergoes dehydration as it approaches the cake outlet 109, and becomes near the cake outlet 109 in the filtration chamber 110. The dehydrated cake will stay. Then, after a lapse of a predetermined time from the start of the operation, when the movable valve 107 of the back pressure device is opened, the first dewatered cake that has stayed near the cake outlet 109 is pushed out by the subsequent dewatered cake. However, it is discharged outside from the cake outlet 109. When the first dewatered cake is discharged, the start operation is completed and the operation shifts to steady operation.

In steady-state operation, with the movable valve 107 of the back-pressure device shown in Fig. 12 open, treatment is performed from the stock solution supply port 108 into the filtration chamber 110 as in the start operation. The undiluted solution is successively introduced and the screen 105 is rotated at a predetermined speed to continuously filter and dehydrate the treated undiluted solution so that the dehydrated cake is discharged from the cake outlet 109. For such steady operation Regarding the filtration and dewatering operations from the introduction of the undiluted solution to the discharge of the dehydrated cake, there is basically no difference from the above-mentioned start operation, but the supply amount of the undiluted solution and the screen 105 The dehydration cake can be discharged at a desired degree of dehydration by appropriately adjusting the rotation speed of and the degree of opening of the movable valve 107 of the back pressure device.

As described above, the rotary compression filter 101 can rotate the inner ring spacer 103 and the screen 105 at a low speed, and can convert the undiluted solution into a liquid (water) and a solid (a dewatered cake). In addition, energy consumption and noise are low, and the outer casing is hermetically closed. It has the advantage of being easy to control, and that in the case of waste disposal, odor generation can be minimized.

However, the rotary compression filter 101 has the following problems. That is, the dehydrated cake 111 is discharged to the outside from the cake outlet 109 in a state as shown in FIG. 10, and among them, a relatively lower part close to the outer ring spacer 104 is shown. (For example, the dewatered cake at the position indicated by L in this figure) is discharged from a relatively high position near the partition plate 106 (for example, H in this figure). There is a problem that the degree of dehydration is low (that is, the water content is high) as compared with the dehydrated cake at the site shown.

Such a problem is peculiar to this kind of rotary compression filter 101, and its cause is considered to be roughly as follows. First, as shown in FIG. 11, since the screen 105 rotates in the direction of arrow B, the frictional force between the dehydrated cake and the screen 105 is determined by the rotation direction of the screen 105. That is, it acts in the direction of arrow F (F1 to F5) shown in FIG. Of these, just below the rotation axis 102, the directions F1 and F2 in which the frictional force acts coincide with the traveling direction D4 of the dewatered cake. When the force further proceeds from the positions of Fl and F2 to the cake exit 109 side, the frictional force is directed to the direction of F3 to F5, that is, to the bottom surface 106c of the partition plate 106. It will work once.

For this reason, the dewatered cake located at F1 proceeds in the direction of F3 according to the frictional force with the screen 105, but at the position of F3, the frictional force is reduced by the partition plate 106. The dewatered cake that has progressed from the position of F1 because it is acting toward the bottom surface 106c, is pressed against the bottom surface 106c of the partition plate 106, and along the bottom surface 106c. It will advance to the position of P1. While the dewatered cake located at F 1 reaches the position of P 1 along the bottom surface 106 c of the partition plate 106 from the position of F 1 to the position of P 1, the outer side of F 1 (outer ring spacer 10 0 The dehydrated cake located on the (4) side constantly moves toward the bottom surface 106c of the partition plate 106 according to the frictional force acting in the direction of F3 and F4, so-called force Therefore, near the bottom surface 106 c of the partition plate 106, particularly near P 1, the dewatered cake is compressed by high pressure, and the compression is caused by the particles of the dewatered cake being mutually separated. Is performed while changing the relative position.

On the other hand, the dewatered cake located at F2 proceeds in the direction of F5 according to the frictional force with the screen 105, and is pushed out in the direction of P2 by the subsequent dewatered cake, but at the position of F5, Since the frictional force acts toward the bottom surface 106 c of the partition plate 106, a part of the dewatered cake located at F 2 becomes part of the partition plate while traveling to the position P 2. It will flow to 106 side. Accordingly, the density and pressure of the dewatered cake at the position of P 2 are lower than those of the dewatered cake at the position of P 1, and the collision of force as occurs at a portion near the partition plate 106 is as follows. Since it does not occur near P2, the relative position of the fine particles in the dehydrated cake is unlikely to change.

Due to such an action, the dewatered cake in the filtration chamber 110 is separated from the dewatered cake. At a portion near the wall plate 106, dehydration proceeds to some extent, and conversely, at a portion near the outer ring spacer 104, the cake outlet 1 is not so strongly compressed and has a low degree of water removal. It is discharged outside from 09.

In addition, in the conventional rotary compression filter 101 shown in FIG. 7, the number of rotations of the rotating shaft 102, the amount of undiluted solution supplied, and the back pressure device at the cake outlet 109 are set. The operation is performed by controlling the movable valve 107, and even when the rotation speed of the rotating shaft 102 and the supply amount of the undiluted solution are constant, the discharge is achieved by adjusting the back pressure in the back pressure device. The degree of water removal in the dewatered cake can be controlled to some extent.

However, if the back pressure is increased in order to obtain a higher degree of dehydration, the cake passage 1 12 in FIG. 9 (the part of the filtration chamber 1 110 other than the screen section, and the cake exit from the end of the screen section) The pressure inside the space up to 109 increases, and the friction between the inner wall of the cake passage 1 1 2 and the dewatered cake increases, which hinders the movement of the dewatered cake and causes clogging. However, the internal pressure may damage the device.

The present invention can solve the above-mentioned problems by slightly improving the conventional rotary compression filter, and can dramatically improve the average degree of dewatering of the discharged dewatered cake. It is an object of the present invention to provide a rotary compression filter that can be expected, and that can also improve the dewatering efficiency and can smoothly discharge a dewatered cake. Disclosure of the invention

According to the present invention, a processing stock solution is continuously introduced into a filtration chamber having a rectangular cross section and extending in an annular shape, and at least one wall surface constituting the filtration chamber is continuously rotated in a direction toward the end of the filtration chamber. By moving it, An apparatus for sequentially moving and compressing the undiluted solution in the terminal direction by friction with the rotating wall, wherein at least one wall constituting the filtration chamber is formed of a material having water permeability. Thus, in the rotary compression filter configured to remove water from the processing stock solution during the compression of the processing stock solution and discharge the remaining dehydrated cake to the outside from the cake outlet through the cake passage, In order to solve such a problem, a pressurizing means is provided in the filtration chamber, so that the cross-sectional area of the filtration chamber gradually decreases in accordance with the moving direction of the untreated solution or the dewatered cake.

With such a configuration, it is possible to compress the dewatered cake in a direction perpendicular to the moving direction of the dewatered cake, and as a result, it is possible to improve the average degree of dewatering of the discharged dewatered cake.

The filtration chamber is fixed around a rotation axis and rotates along the rotation axis. An inner peripheral surface of the inner ring spacer and an outer ring spacer disposed outside the inner ring spacer and held by an outer casing. The inner peripheral surface of the spacer and the inner peripheral edge are respectively fixed on both side surfaces of the inner ring spacer, and the outer peripheral edge portion is arranged in a position and size such that the outer peripheral edge is in contact with both side surfaces of the outer ring spacer. And the inner surfaces of the two screens thus formed. By rotating the rotation shaft, each inner surface of the screen is continuously rotated and moved toward the terminal end of the filtration chamber. Preferably, in this case, the pressurizing means in the filtration chamber can be provided on either the inner ring spacer side or the outer ring spacer side. When the pressurizing means is provided on the inner ring spacer side, the screen has a large number of at least two types of small holes with different diameters, and the small diameter holes are arranged on the outside with the large diameter small holes. If the pressurizing means is formed so as to close small holes with a large diameter from the inside at locations where the pressure in the filtration chamber becomes higher, it is expected that the dehydration efficiency of the entire device will improve. Can be.

Further, if a pressure plate is provided in the filtration chamber as the pressure means and the pressure plate is configured to be vertically displaceable, it is possible to set the position of the pressure plate suitable for steady operation. Further, it is possible to prevent the dewatering cake from being clogged in the cake passage. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a sectional view showing a basic structure of a first embodiment of a rotary compression filter 1 according to the present invention.

FIG. 2 is a cross-sectional view showing a basic structure of a second embodiment of the rotary compression filter 1 according to the present invention.

FIG. 3 is a sectional view showing a basic structure of a third embodiment of the rotary compression filter 1 according to the present invention.

FIG. 4 is a sectional view showing a basic structure of a rotary compression filter 1 according to a fourth embodiment of the present invention.

FIG. 5 is a front view of a screen 5 used in the rotary compression filter 1 of FIG.

FIG. 6 is a sectional view showing a basic structure of a fifth embodiment of the rotary compression filter 1 according to the present invention.

FIG. 7 is a partially cutaway perspective view showing the basic structure of a conventional rotary compression filter 101. As shown in FIG.

FIG. 8 is a cross-sectional view of the rotary compression filter 101 of FIG. 7 taken along line AA.

FIG. 9 is a cross-sectional view of the rotary compression filter 101 of FIG. 7 taken along line CC.

Fig. 10 shows the rotary compression filter 101 of Fig. 7 with cake outlet 109 It is an enlarged sectional view nearby.

FIG. 11 is a cross-sectional view for explaining the operation of the rotary compression filter 101 of FIG.

FIG. 12 is an explanatory view of the movable valve 107 of the back pressure device provided near the cake outlet 109 of the rotary compression filter 101 of FIG. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view showing a structure of a first embodiment of a rotary compression filter 1 according to the present invention. This rotary compression filter 1 is basically composed of a rotating shaft 2, an inner ring spacer 3, an outer ring spacer 4, two donut-shaped screens 5, and a partition plate, as in the conventional one. 6, and an outer casing (not shown), a driving device, etc., and a filtration chamber 10 (formed between the inner ring spacer 3 and the partition plate 6 and the outer ring spacer 4). It is a rectangular space with a cross section, and has a portion (annular portion) extending in a ring (C-shape) and a portion (straight portion) extending in a straight line. This is one of the walls constituting the filtration chamber 10 into which the processing stock solution is continuously introduced through the stock solution supply port 8 through the space and the cake outlet 9 through the portion and the straight portion. By continuously rotating the screen 5 toward the end of the filtration chamber 10, the filtration chamber 1 is rotated. In 0, the processing stock solution is sequentially moved in the direction of arrow D by friction with the screen 5 and compressed, and at this time, water is removed from the processing stock solution through the screen 5 formed of a material having water permeability, and the remaining The dewatered cake is discharged from the cake outlet 9 to the outside.

As is apparent from FIG. 1, the rotary compression filter 1 is provided with a pressure plate 13 in a filtration chamber 10 as a pressure means. The cross-sectional area of the chamber 10 is configured to gradually decrease in accordance with the moving direction of the processing stock solution or the dewatered cake. For this reason, as the undiluted solution or dehydrated cake proceeds in the filtration chamber 10, the cross-sectional area of the filtration chamber 10 is gradually reduced, and the undiluted solution or dehydrated cake is orthogonal to the direction of travel as it proceeds. Pressure will be generated in the direction of movement.

As described above, the rotary compression filter 1 in the present embodiment can compress the undiluted solution or the dewatered cake not only in the traveling direction of the filtration chamber 10 but also in the direction perpendicular to the traveling direction. In the dewatered cake discharged from the cake outlet 9, a higher degree of dehydration can be obtained. In the present embodiment, the pressing plate 13 is provided along the outer peripheral surface 3 a of the inner ring spacer 3 and the bottom surface 6 c of the partition plate 6, and the pressing plate 13 is mainly formed of a screen. While the cross section of the filtration chamber 10 is gradually reduced at the part (the part of the filtration chamber 10 whose side is closed by the screen 5), the cake passage 12 (of the filtration chamber 10) In the part other than the screen part and in the space from the end of the screen part to the cake outlet 9, the bottom surface of the pressure plate 13 and the upper surface 4d of the outer ring spacer 4 are almost parallel. Since the cross-sectional area of the filtration chamber 10 is hardly reduced in the cake passage 12, the efficiency in the filtration chamber 10 is higher than that of the conventional rotary compression filter. Well-filtered and dewatered, the dewatered cake is discharged Thus, a higher degree of dehydration can be obtained.

This point will be described in more detail. The cake passage 12 is vertically formed by the bottom surface of the pressure plate 13 and the upper surface 4 d of the outer race spacer 4, and the side surface is formed by an inner wall of an external casing (not shown). It is not structured so that the water in the cake passage 12 is immediately discharged to the outside.Therefore, in the cake passage 12, the dewatered cake is compressed in a direction orthogonal to the traveling direction. Can effectively separate only water from the dehydrated cake It is not possible to promote the filtration and dehydration of the dewatered cake, but if the dewatered cake is compressed in the screen at right angles to the direction of travel, the water squeezed out of the screen 5 quickly Since the water is discharged to the outside, the filtration and dewatering are performed efficiently, and the dewatered cake with a higher degree of dewatering can be discharged.

In the present embodiment, the screen 5 is formed of a smooth metal plate having a large number of small holes. However, if the screen 5 is made of a porous material having water permeability, for example, a plastic material may be used. Alternatively, it may be formed of a sintered body of metal or ceramic.

FIG. 2 is a sectional view showing a structure of a second embodiment of the rotary compression filter 1 according to the present invention. As shown in this figure, the rotary compression filter 1 according to the present embodiment has a pressure plate 13 provided along the upper surface 4 d of the outer ring spacer 4, and a filter at the screen. The structure is such that the sectional area of the chamber 10 is gradually reduced. Therefore, similarly to the rotary compression filter 1 in the first embodiment, the processing stock solution or the dewatered cake traveling in the filtration chamber 10 can be compressed in a direction orthogonal to the traveling direction. However, the compression is performed in the screen portion where the squeezed water is quickly discharged to the outside from the screen 5, so that the filtration and dewatering can be performed efficiently as compared with the conventional rotary compression filter 1. In addition, the dewatered cake can be discharged at a higher dehydration degree.

In addition, in the conventional rotary compression filter, the dewatered cake near the outer ring spacer did not easily change the relative position of the fine particles, and the degree of dehydration was low due to low compression. In the rotary compression filter 1 of the embodiment, the filtration and dehydration of the dewatered cake at a portion close to the outer ring spacer 4 (for example, a portion indicated by P in FIG. 2) is promoted, and a higher dehydration degree is obtained. can get. This is due to the pressurization provided along the outer ring This is because the action of the plates 13 deforms the fine part (collection of fine particles) in the dewatered cake near the outer ring spacer 4 and increases the chance of extruding the water surrounded by the collective particles. .

In each of the first and second embodiments, an example is shown in which a single pressure plate 13 is attached to one device, but the number of pressure plates 13 is not necessarily limited to one. The pressure plate 13 as shown in Fig. 1 and the pressure plate 13 as shown in Fig. 2 are combined, the dimensions are adjusted appropriately, and both are You may comprise so that it may be provided in the compression filtration machine 1.

As for the pressurizing means, as in the first and second embodiments (FIGS. 1 and 2), in addition to the partition plate 6 or the outer ring spacer 4, the pressurizing means is not necessarily separate from them. It is not necessary to provide the pressure plate 13 as an independent member, and by forming the partition plate 6 or the outer ring spacer 4 itself in a shape and dimensions that gradually reduce the cross-sectional area of the filtration chamber 10, It is also possible to adopt a configuration in which the undiluted solution or dewatered cake is compressed in a direction perpendicular to the traveling direction.

FIG. 3 is a cross-sectional view showing the structure of a rotary compression filter 1 according to a third embodiment of the present invention. In the present embodiment, the pressurizing portion 6e at the lower portion inside the partition plate 6 has a function as a pressurizing means, and the displacement pressurizing plate 13a pivots at an arbitrary point as shown in FIG. As 16, it is configured such that the cake outlet 9 side can be displaced upward and downward, or that it can be displaced (i.e., oscillates) at a constant cycle. A description of a mechanism for displacing the pressing plate 13 is omitted, but a cam mechanism, a crank mechanism, or the like can be used as appropriate.

By configuring the pressure plate 13 to be displaceable in this way, it is possible to set the position of the pressure plate 13 suitable for a steady operation. During the start-up operation, a sufficient amount of undiluted solution or dewatered cake is accumulated in the machine, and a dewatered cake that has not yet been sufficiently filtered and dewatered is discharged from the cake outlet 9 until the internal pressure sufficient for filtration and dehydration is generated. It can also be used to make the cake passage 12 extremely narrow so that it is not discharged to the outside. Therefore, the back pressure device having the movable valve 107 as shown in FIG. 12 used in the conventional rotary compression filter is omitted in the rotary compression filter 1 in the present embodiment. You can also.

In addition, when the pressure plate 13 is configured to be swingable, the dewatered cake is prevented from clogging in the cake passage 12 and stable operation is possible even when the maximum pressure is set high. .

FIG. 3 shows an example in which the pressure plate 13 that can be displaced or oscillated is provided on the partition plate 6 side. However, as shown in FIG. It is possible to make it swingable even if it is provided along the support 4, and in this case, the same effect as described above can be expected. Further, the pressing plate 13 may be configured so as to be entirely displaced, or may be configured so that only a part thereof is displaced.

Further, the displacement of the pressure plate 13 as shown in FIG. 3 can be applied to automatic control. For example, if the solid concentration or solid component of the undiluted solution has a temporal or seasonal fluctuation, if the operating conditions such as the rotating shaft, the amount of undiluted solution supply, and the displacement of the pressure plate 13 are fixed, Due to the difference in the properties of the undiluted solution, the degree of dehydration of the discharged dehydrated cake will also change. However, a pressure sensor is attached to the surface of the pressurizing plate 13 in the filtration chamber 10, and various parts in the filtration chamber 10 are installed. If the pressure of the filtration plate 10 is detected and the pressure plate 13 is displaced accordingly, the pressure inside the filtration chamber 10 can be easily controlled, and the degree of dewatering of the discharged dewatered cake can be controlled as desired. Can be controlled within the range.

In the case of a conventional rotary compression filter, the back pressure is measured using the same detection device. When the movable valve 107 (see Fig. 12) of the device is displaced, the integrated value of the frictional force of the dehydrated cake from the inner wall of the cake passageway 112 and the filtration chamber 110 to the cake outlet 109 is obtained. Was an error factor, and satisfactory control was not possible. FIG. 4 is a sectional view showing a structure of a rotary compression filter 1 according to a fourth embodiment of the present invention. As is clear from this figure, in the present embodiment, the partition plate 6 has a shape such that the cross-sectional area of the filtration chamber 10 is gradually reduced, and the partition plate 6 itself functions as a pressurizing means. It has become . More specifically, in the conventional rotary compression filter 101 (see FIG. 9), the bottom surface 106 c of the partition plate 106 is located on the upper surface 1 of the straight portion of the outer ring spacer 104. However, the bottom surface 6 c of the partition plate 6 in the present embodiment is not provided with the inner ring spacer 3. From the inner end 6a, which makes surface contact with the outer peripheral surface 3a, to the outer end 6b, first in a direction substantially perpendicular to the upper surface 4d of the linear portion of the outer race spacer 4, and then gradually It extends to the cake exit 9 side while drawing a curve, and finally, in the cake passage 12, it extends almost parallel to the outer ring spacer 4 and reaches the outer end 6 b, and is filtered. The cross-sectional area of the chamber 10 is gradually reduced at the screen.

Therefore, also in the present embodiment, the dewatered cake traveling in the filtration chamber 10 can be compressed in the screen section in a direction orthogonal to the traveling direction, and the filtration can be performed more efficiently than in the conventional rotary compression filter. · Dehydration can be performed, and a dehydrated cake with a higher degree of dehydration can be obtained.

Also in the present embodiment, the screen 5 is formed of a smooth metal plate having a large number of small holes and having water permeability. And, as shown in FIG. 5, those small holes have different diameters in the zone G1 on the inner peripheral edge 5a side and the zone G2 on the outer peripheral edge 5b side. Is established . More specifically, a small hole 14 having a diameter of about 0.16 to 0.20 mm (preferably 0.18 mm) and a diameter similar to the conventional one is provided in the zone G1. Zone G2 has pores 1 having a diameter of about 0.11 to 0.15 mm (preferably 0.13 mm) and smaller in diameter than pores 14 of Zone G1. 5 are arranged. That is, on the screen 5, the small holes 15 having a small diameter are arranged on the outer side (on the outer peripheral edge 5b side) of the small holes 14 having a large diameter. The line 5c shown in FIGS. 4 and 5 is a boundary between the zone G1 and the zone G2.

As described above, in the present embodiment, the small holes 15 having a smaller diameter than the conventional one are arranged on the outer peripheral edge 5 b side of the screen 5, so that the processing can be performed more than the conventional rotary compression filter. The trapping efficiency of the suspended solids (fine particles) in the stock solution by screen 5 has been improved. To explain this point in more detail, first, the undiluted solution introduced into the machine is filtered by the filtration zone K (Fig. 4) within a range of about 200 ° from the upper surface 6d of the partition plate 6 in the filtration chamber 10. ), Most of the water (free water) passes through the small holes 14, 15 of the screen 5 and is discharged out of the filtration chamber 10.

The dewatering action in the filtration zone K is based on the fact that the supply pressure of the undiluted solution is relatively low (less than or equal to 0.1 MPa). There is no danger of being discharged out of the filtration chamber 10 through the large (small diameter) pores 14, but in the compression zone J (see Fig. 4), the pressure in the filtration chamber 10 is low. However, due to the partition plate 6 functioning as a pressurizing means, the pressure in the filtration chamber 10 gradually increases (up to about 0.6 MPa) as the undiluted solution or dewatered cake progresses. Fine particles in the cake may be discharged through the small holes 14 of the screen 5 to the outside of the filtration chamber 10 due to the increased internal pressure (note that the zone G on the outer peripheral edge 5 b side). The small holes 1 5 arranged in 2 However, since the diameter is smaller than in the past, even if the internal pressure of the filtration chamber 10 increases, the possibility that the fine particles will escape is not so large. However, in this case, the efficiency of capturing fine particles is reduced.

However, in the present embodiment, since the partition plate 6 is formed so as to gradually reduce the cross-sectional area of the filtration chamber 10, the processing solution which is located on the inner ring spacer 3 side in the filtration chamber 10 is not used. Alternatively, the dewatered cake is gradually moved away from the inner ring spacer 3 as it progresses through the filtration chamber 10 by the partition plate 6, and is moved to the outer ring spacer 4 side. Then, at the position in the filtration chamber 10 where the internal pressure is increased by the partition plate 6 (the position indicated by M in FIG. 4), the processing stock solution or the dewatered cake is removed from the outer peripheral edge of the screen 5. 5b, which passes through the area corresponding to the zone G2 (the zone in which the small holes 15 having a smaller diameter than the conventional one are arranged), and the zone on the inner peripheral edge 5a side of the screen 5. The small hole 14 having the same diameter as the conventional one disposed in G 1 is closed from the inside by the partition plate 6. Therefore, the fine particles of the undiluted solution or dehydrated cake are not discharged out of the filtration chamber 10 from the small holes 14, and the problem of a decrease in the efficiency of capturing the fine particles in the undiluted solution can be suitably avoided. ing.

In the present embodiment, two types of small holes 14 and 15 having different diameters are provided on the screen 5, and the small diameter holes 15 are arranged outside the large diameter small holes 14. However, for example, 10 types (or more) of small holes with different diameters are provided on the screen 5, and the diameter of the provided small holes is gradually reduced from the inside to the outside. You may.

Finally, a fifth embodiment of the rotary compression filter 1 in which the cake passage 12 is not horizontal will be described with reference to FIG. The explanation so far is Although an example in which the key passages 12 are arranged substantially horizontally has been shown, this is for convenience of explanation, and in the present invention, the angle of the cake passages 12 is not limited at all. If the cake passage 12 is located at the bottom of the machine and there is no mechanism to close the cake passage 12 and the cake outlet 9, at the start of operation, a part of the undiluted solution will flow through the small holes 14 and 1 in the screen 5. A device for temporarily closing the cake passage 12 because it flows from the cake outlet 9 through the cake passage 12 without passing through the device 5 (for example, as shown in FIG. 12). Back pressure device with movable valve 107). On the other hand, as shown in Fig. 6, if the cake passage 12 faces upward, it is possible to wait for the stock solution or dewatered cake to accumulate without any special measures at the start of operation. it can.

As described above, the embodiments of the present invention have been described, but the present invention is not limited to these embodiments. Further, in the present specification, the term "water" is used such as "water permeability", "dehydration", and "moisture", but these are used for convenience of explanation, and "oil" and the like are used. It should be noted that this does not mean to exclude but broadly means "liquid". Industrial applicability

The rotary compression filter according to the present invention can be expected to dramatically improve the average degree of dewatering of the discharged dewatered cake, and can expect improvement in dewatering efficiency. In addition, the pressure of the screen portion in the compression zone can be increased by the action of the pressurizing means, and the pressure of the final dewatering portion of the filtration chamber can be increased, and as a result, the degree of dewatering of the entire dewatered cake can be improved. Can be.

Further, when a pressure plate is provided in the filtration chamber as a pressure means, and the pressure plate is configured to be swingable up and down, the width for selecting a stable operation condition is limited. Since it is possible to spread and perform the dehydration treatment with a higher pressure, the degree of dehydration of the dehydrated cake is improved. Furthermore, by automatically controlling the displacement of the pressurizing plate in combination with a signal from a pressure sensor or the like, it is possible to cope with a change in the properties of the stock solution and to keep the dehydration degree of the dewatered cake within a certain range. However, the rotary compression filter of the present invention can be used for the separation of all solid-liquid mixed treatment liquids, but compared with other solid-liquid separators when the solids contained in the undiluted treatment liquid have compaction properties. It offers a particularly significant advantage. For example, fruits and vegetables can be used to separate juice from shredded and crushed material, to separate soy milk, and to treat liquids containing fine fibers such as papermaking wastewater. In addition, in the case of sludge dewatering at a sewage treatment plant, as described above, since the part other than the cake outlet can be made a closed structure, environmental pollution due to bad smell and deterioration of the working environment can be minimized. When dewatered cake is incinerated, fuel can be saved and energy can be saved.

Claims

The scope of the claims

1. The treatment stock solution is continuously introduced into the filtration chamber having a rectangular cross section and extending annularly, and at least one wall surface constituting the filtration chamber is continuously rotated and moved toward the end of the filtration chamber. This is a device for sequentially moving and compressing the undiluted solution in the filtration chamber in the terminal direction by friction with the rotating wall surface, wherein at least one wall surface constituting the filtration chamber has water permeability. The rotary compression is formed by removing the water from the processing stock solution when the processing stock solution is compressed by being formed of the material, and discharging the remaining dehydrated cake to the outside from the cake outlet through the cake passage. In the filter, by providing a pressurizing means in the filtration chamber, the cross-sectional area of the filtration chamber gradually increases in accordance with the moving direction of the processing stock solution or the dewatered cake. A rotary compression filter characterized by being configured to reduce.

2. The filtration chamber is fixed around a rotation axis, and has an outer peripheral surface of an inner ring spacer that rotates according to the rotation axis; an inner peripheral surface of an outer ring spacer disposed outside the inner ring spacer; The inner surface of each of the two screens whose peripheral edges are fixed on both sides of the inner ring spacer and whose outer peripheral edges are in contact with the dimensions of the outer ring spacer. Wherein the inner surface of the screen is continuously rotated and moved in the direction toward the end of the filtration chamber by rotating the rotating shaft. The rotary compression filter according to the above item.

3. The rotary compression filter according to claim 2, wherein the pressurizing means is provided on an inner ring spacer side in the filtration chamber.

4. The rotary compression filter according to claim 2, wherein the pressurizing unit is provided on an outer ring spacer side in the filtration chamber.

5. The screen has a large number of at least two types of small holes having different diameters, and the small diameter small holes are arranged outside the large diameter small holes on the screen. 4. The rotary compression filter according to claim 3.

6. A pressure plate is provided in the filtration chamber as the pressure means, and the pressure plate is configured to be vertically displaceable. Item 6. The rotary compression filter according to any one of items 5.