JP2001079314A - Filter device and filtering method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance conveying performance and dehydration performance for cake without increasing the load on a driving means. SOLUTION: In the filtering device where plural filter bodies 4, 4a are arranged each of which is provided with plural filter pieces 10, 11 disposed at an interval in the axial direction on a revolving shaft 9 and the filter bodies 4, 4a adjacent to each other are arranged in parallel with their filter pieces 10, 11 inserted into the gap between the adjacent filter bodies, portions 11 of plural filtering pieces are arranged such that the outer peripheral edges are different in the distance from the center of the revolving shaft 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filtration apparatus for separating a filtrate by subjecting sewage sludge, human waste sludge, and other industrial waste sludge to a filtration treatment.

[0002]

2. Description of the Related Art Conventionally, as an apparatus for performing a filtering treatment on the above-mentioned sludge, for example, an apparatus described in Japanese Patent Publication No. 60-18443 is provided. In this apparatus, two or more filter bodies are arranged adjacent to each other in a processing chamber of a processing box to form a filter body row, and two rows are arranged at appropriate intervals. Each filter body is fixed to a rotating shaft by alternately combining an annular filter piece having an eccentric rotating shaft and a spacer that is not eccentric, and the rotating shaft is configured to be rotated by driving means. I have. Further, the filter bodies are made to protrude into gap grooves formed between two filter pieces adjacent to each other.

When the sludge stock solution flows into the processing chamber, the stock solution enters the gap groove, and the filtrate passes between the filter piece and the spacer (if the filter piece has a guide hole, this guide hole). At the same time as the liquid is discharged from the filtrate discharge port, fine particles are gradually left in the gap groove and filled. Next, the space between the fine particles serves as a filtration hole, and passes the water in the stock solution. The fine particles between the gaps
It is scraped out between the filter rows by the rotation of the adjacent filter pieces, laminated on the outer circumference of the filter body to form a cake, and discharged after being transported to the cake outlet by the rotation of the filter body.

[0004]

However, the above-mentioned conventional filtering apparatus has the following problems. Since all of the filter pieces are eccentric in the same direction with respect to the rotation axis, the timing at which the distance between the spacer and the filter piece of the adjacent filter body becomes the narrowest coincides with the length direction of the filter body. At this time, the resistance for rotating and driving the filter body increases. In other words, there is a problem that the load on the driving unit becomes large due to the large fluctuation of the driving torque.

[0005] On the other hand, cake transport depends on the frictional resistance between the outer peripheral edge of each filter piece and the solid material. However, if the cake is hardened by long-term operation, the cake is hardly deformed between the filter bodies. There was a possibility that slippage occurred between the filter and the cake, which hindered cake conveyance. In addition, since the dehydration of the cake is mainly performed by a capillary phenomenon, there is a problem that the progress of the dehydration is stagnated due to the cake being hardened. In particular, these problems were more remarkable when the cake hardly changed its shape in the direction along the rotation axis due to the fact that all the filter pieces were eccentric in the same direction.

The present invention has been made in consideration of the above points, and has as its object to provide a filtration device that improves the cake transport function and dewatering function without increasing the load on the driving means. I do.

[0007]

In order to achieve the above object, the present invention employs the following constitution. The filter device according to claim 1, comprising a plurality of filter bodies each having a plurality of filter pieces arranged with a gap in a rotation axis direction, and the filter bodies protruding into a gap between the filter bodies adjacent to each other to be arranged in parallel. In the filter device according to the present invention, a part of the plurality of filter pieces is arranged such that an outer peripheral edge thereof is different in distance from the center of the rotation axis.

[0008] Therefore, in the filtration device of the present invention, the point where the distance between the filter bodies and the filter pieces of the adjacent filter bodies becomes the narrowest occurs only in a part of the rotation axis direction. The driving load does not become large. Also, with the rotation of the filter body, the longest outer peripheral edge of some filter pieces protrudes to the outer peripheral side, so that the cake extending in the rotation axis direction is partially crushed. The cake can be bent in the direction of the rotation axis corresponding to the position. Therefore, the contact portion between the filter body and the cake is constantly updated, and the capillary phenomenon can be continued. Further, in the protruding filter piece, not only the outer peripheral edge but also the side surface frictional force is applied, so that the cake conveying function is improved. Furthermore, in order to obtain the same effect, when a filter piece having a diameter slightly larger than that of the filter piece is arranged in place of the filter piece in which the outer peripheral edge is arranged at a different distance from the center of rotation, the piercing of the cake is reduced. The continuous operation forms a groove in the cake and reduces the frictional force. However, in the filtration device of the present invention, the frictional force does not decrease because the crushing of the cake is performed intermittently. In addition, as a filter piece whose outer peripheral edge is different in distance from the center axis center, a substantially disc-shaped filter piece is eccentric with respect to the rotation axis, and an elliptical shape, an egg shape, an oval shape, etc. The effect is obtained.

According to a second aspect of the present invention, there is provided the filtering device according to the first aspect, wherein the some filter pieces are disposed on both sides of a filter piece having an outer peripheral edge having the same distance from the center of the rotation axis. It is characterized by being performed.

Therefore, in the filtration device of the present invention, even when the shortest outer peripheral edge of some filter pieces is located in the gap between the adjacent filter bodies, the outer peripheral edge of the filter piece disposed between them is relatively outer. Since it protrudes to the side, the cake in the gap can be scraped out.

According to a third aspect of the present invention, there is provided the filtering device according to the first aspect, wherein the partial filter pieces and the filter pieces having an outer peripheral edge having the same distance from the center of the rotation axis are provided every predetermined number of sheets. It is characterized by being arranged alternately.

Therefore, in the filtering device of the present invention, the cake can be bent in the direction of the rotation axis into a wave shape corresponding to the position of a predetermined number of some filter pieces.

According to a fourth aspect of the present invention, in the filtering device according to any one of the first to third aspects, a distance from the center of the rotation shaft is different in the gap into which the part of the filter pieces enters. A spacer having an outer peripheral edge is provided.

Therefore, in the filtration device of the present invention, even if the distance between the outer peripheral edge of a part of the filter piece that enters the gap due to the rotation of the filter and the rotation axis of the adjacent filter is changed, a part of the filter is not removed. By varying the distance from the center of the rotation axis of the outer periphery of the spacer to the filter pieces, it is possible to prevent the gap between the outer periphery of some filter pieces and the spacer from becoming excessive.

According to a fifth aspect of the present invention, there is provided the filtration device according to any one of the first to fourth aspects, wherein the rotation speed of the filter located on the cake discharge direction side after the filtration is different from that of another filter. The rotation speed is lower than the rotation speed.

Therefore, in the filtration device of the present invention, the cake before being carried out is compressed between filter bodies having different rotation speeds, so that the dewatering efficiency can be improved.

According to a sixth aspect of the present invention, there is provided the filtration method, wherein a plurality of filter bodies each having a plurality of filter pieces arranged with a gap in a rotation axis direction are arranged by projecting the filter pieces into a gap between the filter bodies adjacent to each other.
In the filtration method of rotating the filter body and discharging the cake that has been dewatered and filtered, a part of the plurality of filter pieces is arranged such that an outer peripheral edge is different in distance from the center of the rotation axis, and the cake is placed in the filter. It is characterized in that it is transported while being pushed by some filter pieces.

Therefore, in the filtration method of the present invention, a point where the distance between the filter bodies and the filter pieces of the adjacent filter bodies becomes the smallest occurs only in a part of the rotation axis direction. The driving load does not become large. Also, with the rotation of the filter body, the longest outer peripheral edge of some filter pieces protrudes to the outer peripheral side, so that the cake extending in the rotation axis direction is partially crushed. The cake can be bent in the direction of the rotation axis corresponding to the position. Therefore, the contact portion between the filter body and the cake is constantly updated, and the capillary phenomenon can be continued. Further, in the protruding filter piece, not only the outer peripheral edge but also the side surface frictional force is applied, so that the cake conveying function is improved. Furthermore, if a piece of filter having a diameter slightly larger than one part is arranged, the crushing of the cake is continuously performed, so that a groove is formed in the cake, and the frictional force is reduced. In the filtration device of the present invention, since the crushing of the cake is performed intermittently, the frictional force does not decrease. In addition, as a filter piece whose outer peripheral edge is different in distance from the center axis center, a substantially disc-shaped filter piece is eccentric with respect to the rotation axis, and an elliptical shape, an egg shape, an oval shape, etc. The effect is obtained.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of a filtration device according to the present invention will be described with reference to FIGS. Here, a description will be given assuming that the filter piece has a disk shape.
In the filtration device 1 shown in FIG. 1, a plurality of filter bodies 4 and 4a are arranged in parallel in upper and lower two stages in a processing chamber 3 of a processing box 2, and a sludge stock solution (hereinafter, referred to as stock solution) is provided in the processing box 2. Supply port 5,
A cake discharge port 6 is provided, and as shown in FIG. 2, a filtrate chamber 7 and a drive chamber 16 are provided on both sides of the processing chamber 3 and are partitioned by opposed partitions 12a and 12b, respectively. A filtrate outlet 8 is provided below the filtrate chamber 7.

The rotating shafts 9 of the filter bodies 4 and 4a are arranged in parallel with each other, and one end thereof (the left side in FIG. 2) has a partition wall 12a.
The disk 20 which is rotatable and supported in a watertight manner is fixed. In the disk 20, through holes 20a that open into the processing chamber 3 and the filtrate chamber 7 are formed annularly at intervals around the rotation axis 9. The other end of the rotating shaft 9 (the right side in FIG. 2)
The partition wall 12b is rotatably and water-tightly supported by the partition wall 12b. A transmission gear 17 is fixed to an end of the rotating shaft 9 protruding into the drive chamber 16, and a transmission gear 19 supported by a shaft 18 meshes with the transmission gear 17. A sprocket (not shown) is provided on the shaft 18, and a chain for transmitting the rotational drive of driving means (not shown) such as a motor is engaged with the sprocket. This chain consists of two filter bodies 4 lined up and down,
4a, and these two filter bodies 4, 4
a is rotated clockwise in the upper part and counterclockwise in the lower part at the same speed. The filter bodies 4 and 4a rotate at the same speed, respectively. However, the upper and lower filter bodies 4a located on the cake discharge port 6 side (the cake discharge direction side) are:
By interposing an idler gear (not shown) between the transmission gear 17 and the transmission gear 19, the filter body 4 rotates at a lower speed. Note that two driving machines having different rotation speeds may be used without using the idler gear.

As shown in FIGS. 3 and 4, each filter body 4, 4a has a disk disposed concentrically with the rotating shaft 9 so that the outer peripheral edge is at the same distance from the center of the rotating shaft 9. Shaped filter 1
0 and an eccentric filter piece 11 eccentrically arranged with respect to the rotating shaft 9 so that the outer peripheral edge is different from the center of the rotating shaft 9 in a disk shape. Installed. The width of the gap 13 is
The thickness is set slightly larger than the thickness of the eccentric filter 11. The eccentric filter pieces 11 are arranged eccentrically in opposite directions (180 degrees) on both sides of the filter piece 10 and constitute a set including the filter piece 10 sandwiched therebetween. Then, a plurality of such sets are provided at a predetermined pitch in the axial direction of the rotating shaft 9 (four sets in FIG. 2).
Is provided. The total number of the filter pieces 10 and 11 constituting the set is 10 to 60% of the total number of filter pieces of one filter body 4 (or 4a) (determined according to the properties of the sludge to be treated).
Is preferred.

The filter bodies 4 and 4a arranged in parallel are arranged so that the filter piece 10 and the eccentric filter piece 11 protrude into the gap 13 between the adjacent filter bodies 4 and 4a. In the gap 13, the gap into which the filter pieces 10 that do not constitute the above set are inserted is:
A gap formed by a spacer 14 having an outer diameter set so as to form a slight gap with the outer peripheral edge of the filter piece 10, and into which the filter piece 10 and the eccentric filter piece 11, which constitute the above set, are inserted. Is formed by a small diameter spacer 15 having a smaller diameter than the spacer 14. As shown in FIG. 4, the filter piece 10 and the eccentric filter piece 11 are provided with filtrate guide ports 10 a and 11 a, respectively, and the spacer 14 and the small-diameter spacer 15 are provided with concave portions 14 a and 15 a, respectively. At the locations where they are continuous, and guides the filtrate between adjacent gaps 13. The eccentric directions of the filter bodies 4 and 4a do not have a correlation with each other, so that the workability at the time of assembling the filter bodies 4 and 4a is configured to be easy.

The operation of the filtration device having the above configuration will be described. First, the stock solution supply port 5 is rotated while rotating the filter bodies 4 and 4a.
Add the stock solution from. Moisture in the undiluted solution falls below the processing chamber 3 through the gap 13 or the filtrate guide port 1
The liquid is sent to the filtrate chamber 7 through the through-holes 20a from the recesses 14a and 15a, and is discharged from the filtrate discharge port 8. At the same time, fine particles in the stock solution gradually remain in the gap 13. Thereafter, the space between the fine particles becomes a filtration hole, through which the water in the stock solution passes.

The fine particles remaining in the gap 13 are scraped out between the filter rows by the filter pieces 10 and the eccentric filter pieces 11 of the adjacent filter bodies 4 and 4a, and the moisture is gradually removed. The cake is laminated on the outer periphery of the filter bodies 4 and 4a. The cake is discharged from the cake outlet 6 by rotating the filter bodies 4 and 4a.
Transported to

Here, the cake to be transported is
Since the outer peripheral edge of the eccentric filter piece 11 provided at a is partially crushed and bent (see C in FIG. 2), the contact portions with the filter bodies 4 and 4a are constantly updated, and the capillary phenomenon continues. Is done. In addition, since the eccentric filter 11 is intermittently generated with the rotation of the piercing filter bodies 4 and 4a with respect to the cake and the groove which the eccentric filter 11 scrapes off does not remain, the eccentric filter 11 does not remain.
Of the frictional force against the cake can be prevented. In addition, since the eccentric filter 11 rushes into the cake every round, the frictional force with the cake acts not only on the outer peripheral edge but also on the side surface,
Convey the cake with stronger force.

The cake reaching the space between the filter bodies 4 and 4a is compressed by the difference between the rotation speeds of the filter bodies 4 and 4a and the interval between the upper and lower filter rows is reduced.
From the device.

In the filtration device of the present embodiment, the filter bodies 4, 4
Since only a part of the filter piece provided in a is the eccentric filter piece 11, the portion where the distance between the outer peripheral edge of the eccentric filter piece 11 and the small-diameter spacer 15 becomes the narrowest is a part in the direction of the rotating shaft 9. It can be prevented that the load on the driving means for rotating the filter bodies 4 and 4a becomes excessively large. Further, since the conveyed cake can be bent or the capillary phenomenon can be maintained, the dewatering function can be improved. Furthermore, the eccentric filter 11 is intermittently crushing the cake, and the contact area between the eccentric filter 11 and the cake is increased, so that the frictional force of the filter bodies 4, 4a on the cake is increased. The transport function is also improved.

In this embodiment, the filtration efficiency is also improved by compressing the cake before discharging. Further, in the present embodiment, the recesses 14a and 15a are provided in the spacer 14 and the small diameter spacer 15, respectively, so that the filtrate guide ports 10a and 11a can be closer to the center. Accordingly, the area where the filter piece 10 and the eccentric filter piece 11 protruding into the gap 13 cross the filtrate guide ports 10a, 11a is reduced, so that the efficiency of filtrate discharge is also improved.

In the above embodiment, a pair of eccentric filter pieces 11 constituting a set are configured to be eccentrically arranged in opposite directions. However, the present invention is not limited to this.
It may be eccentrically arranged in the same direction across 0, in this case,
It is conceivable that the longest outer peripheral edge of the eccentric filter 11 is separated from the gap 13 and the scraping amount of the gap 13 is reduced. However, the filter 10 between the eccentric filters 11 is pulled by the scraping cake. It does not cause any trouble. As shown in FIG. 5, a set having eccentric filter pieces 11 eccentrically arranged in the same direction is arranged in series in pairs such that the eccentric directions are opposite to each other across the filter piece 10. Is also good. In this case, since the bending of the cake is performed at a smaller pitch, the dewatering function can be further improved.

The arrangement of this set is not limited to the above-described embodiment, but can be variously adopted. For example, as shown in FIG. 6A, a set in which the eccentric filter pieces 11 are arranged in opposite directions to each other is arranged in line symmetry without the filter piece 10 being interposed therebetween.
As shown in (b), the filter pieces 10 are arranged in parallel without sandwiching them, and as shown in (c), the eccentric filter pieces 11
Are arranged in the same direction with the same eccentric direction and without the filter piece 10 interposed therebetween. As shown in (d), the group in which the eccentric filter pieces 11 are arranged in the same direction is Conversely, a filter in which the filter pieces 10 are arranged without being interposed therebetween can also be adopted.

FIGS. 7 and 8 are views showing a second embodiment of the filtration device of the present invention. In these figures,
The same components as those of the first embodiment shown in FIGS. 1 to 6 are denoted by the same reference numerals, and description thereof will be omitted. The difference between the second embodiment and the first embodiment is the arrangement of the eccentric filter 11.

As shown in FIG. 7, in this embodiment, three sets of eccentric filter pieces 11 eccentrically arranged in the same direction constitute a set, and as shown in FIG. In FIG. 7, six filter pieces 10 are alternately arranged. Other configurations are the same as those of the first embodiment.

In the filtration device of the present embodiment, the filter bodies 4, 4
When the cake is transported by the rotation of a, the eccentric filter pieces 11 forming a set bend the cake in a large curved shape, so that the same operation and effect as those of the first embodiment can be obtained.

In this embodiment, the eccentric filter 1 is also used.
Various arrangements can be adopted for the arrangement configuration 1 in addition to the above embodiment.
For example, as shown in FIG.
Eccentrically arranged in the same direction so that they are adjacent to each other, (b)
As shown in the figure, eccentric arrangement in the opposite direction to each other,
Further, as shown in (c), four eccentric filter pieces 11 are arranged so that their eccentric directions are alternately arranged. As shown in (d), a pair of eccentric filter pieces 11 eccentrically arranged in the same direction are sandwiched. One in which eccentric filter pieces 11 eccentric in the opposite direction are arranged on both sides, and two pairs of eccentric filter pieces 11 eccentrically arranged in the same direction are arranged so as to be eccentric in the opposite direction, as shown in (e). , And as shown in FIG.
And the like may be employed in which the eccentricity is arranged adjacent to each other in the same direction.

FIGS. 10 and 11 are views showing a third embodiment of the filtration device of the present invention. In these drawings, the same elements as those of the second embodiment shown in FIGS. 7 to 9 are denoted by the same reference numerals, and description thereof will be omitted. The difference between the third embodiment and the second embodiment is the configuration of the small diameter spacer.

That is, as shown in these figures, the correlation between the filter bodies 4 and 4a is adjusted so that the eccentric directions of the eccentric filter pieces 11 are the same, and the small-diameter spacer 15 has an outer peripheral edge. The eccentric filter piece 11 is eccentrically arranged in the same direction as the eccentric direction of the eccentric filter piece 11 so that the distance from the center of the rotating shaft 9 is different. Other configurations are the same as those of the second embodiment.

In the filtering device of this embodiment, the same operation and effect as those of the second embodiment can be obtained, and in addition to the longest outer peripheral edge of the eccentric filter piece 11 due to the rotation of the filter bodies 4 and 4a. Even if the distance between the center of the rotating shaft 9 of the adjacent filter body changes, the small diameter spacer 15 facing the longest outer peripheral edge is eccentric in the same direction as the eccentric filter piece 11, so that the filter body 4, The gap between the longest outer peripheral edge and the small-diameter spacer 15 between 4 and 4a, 4a can be prevented from becoming excessive, and the efficiency of filtration and dehydration of the undiluted solution can be prevented from lowering.

In the above embodiment, the eccentric filter has a disk shape. However, the present invention is not limited to this. For example, the filter may have an elliptical shape, an egg shape, or an oval shape. In this case, the distance between the center of the rotating shaft 9 and the outer peripheral edge becomes different irrespective of the positional relationship between the filter and the rotating shaft 9.・ Effect is obtained. Furthermore, without using the concentrically arranged filter pieces 10, the above-mentioned elliptical shape, egg shape,
The same operation and effect can be obtained by arranging the filter pieces having an oval shape so that the protruding directions of the longest outer peripheral edges are different.

[0039]

As described above, the filtering device according to the first aspect has a configuration in which a part of the plurality of filter pieces has an outer peripheral edge having a different distance from the center of the rotation axis. This allows
With this filtration device, the effect of improving the dewatering function and the cake transport function can be achieved without an excessive load on the driving means for rotating the filter body.

The filter device according to claim 2 has a structure in which some filter pieces are arranged on both sides of a filter piece having an outer peripheral edge having the same distance from the center of the rotation axis. This allows
In this filtration device, even when the longest outer peripheral portion of some of the filter pieces is separated from the gap, the filter piece placed between them is pulled by the cake to be scraped, so that the cake can be scraped without trouble. Play.

According to a third aspect of the present invention, a filter having an outer peripheral edge having the same distance from the center of the rotating shaft and the above-mentioned part of the filters are alternately arranged for every predetermined number of sheets.
Thereby, in this filtration device, since the cake is bent in a larger curved shape, the effect of improving the dewatering function and the function of transporting the cake can be obtained.

According to a fourth aspect of the present invention, the spacer into which a part of the filter pieces protrudes is provided with a spacer having an outer peripheral edge having a different distance from the center of the rotating shaft. Thereby, in this filtration device, even if the distance between the longest outer peripheral edge of some filter pieces and the center of the rotating shaft of the adjacent filter body fluctuates, the outer peripheral edge of the filter pieces and the outer peripheral edge of the spacer come into contact with each other. Can be suppressed from becoming excessively large, and the effect of preventing the efficiency of filtration and dehydration of the undiluted solution from being lowered can be obtained.

According to a fifth aspect of the present invention, the rotation speed of the filter located on the cake discharge direction side is lower than the rotation speed of the other filter. Thereby, in this filtration device, since the cake can be compressed between these filter bodies, the effect that the filtration efficiency can be improved is obtained.

According to a sixth aspect of the present invention, a part of the plurality of filter pieces is arranged so that an outer peripheral edge thereof has a different distance from the center of the rotating shaft, and the cake is conveyed while being pushed by the filter pieces. It has a configuration. Thereby, in this filtration method, the load of the driving means for rotating the filter body does not become excessive,
The effect that the dehydration function and the cake transfer function can be improved can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention, and is a front cross-sectional view in which a plurality of filter bodies are arranged in two upper and lower stages in a processing chamber.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a view showing the first embodiment of the present invention, and is a detailed view of a main part of filter bodies arranged in parallel with filter pieces protruding into a gap.

FIG. 4 is a sectional view taken along line BB in FIG.

FIG. 5 is a cross-sectional view showing another form of the filter according to the first embodiment of the present invention.

FIG. 6 is a plan view showing various arrangement examples of the eccentric filter in the embodiment of the present invention.

FIG. 7 is a view showing a second embodiment of the present invention, and is a detailed view of a main part of filter bodies arranged in parallel with filter pieces protruding into a gap.

8 is a cross-sectional view in which the filter shown in FIG. 7 is disposed in a processing chamber.

FIG. 9 is a plan view showing various arrangement examples of the eccentric filter in the embodiment of the present invention.

FIG. 10 is a view showing a third embodiment of the present invention, and is a detailed view of a main part of filter bodies arranged in parallel with filter pieces protruding into a gap.

FIG. 11 is a sectional view taken along line DD in FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Filtration device 4, 4a Filter body 9 Rotating shaft 10 Filter piece 11 Eccentric filter piece 13 Gap 15 Small diameter spacer (Spacer)

Claims (6)

[Claims] 1. A filter device comprising a plurality of filter bodies each having a plurality of filter pieces arranged with a gap in the direction of the rotation axis, wherein the filter bodies are arranged in parallel with the filter pieces protruding into a gap between the filter bodies adjacent to each other. The filtering device according to claim 1, wherein a part of the plurality of filter pieces is arranged such that an outer peripheral edge thereof has a different distance from the center of the rotation axis. 2. The filter device according to claim 1, wherein the some filter pieces are arranged on both sides of a filter piece having an outer peripheral edge having an equal distance from the center of the rotation axis. Filtration equipment. 3. The filter according to claim 1, wherein the filter pieces and the filter pieces having an outer peripheral edge having the same distance from the center of the rotation axis are alternately arranged every predetermined number of sheets. Characteristic filtration device. 4. The filtering device according to claim 1, wherein a spacer having an outer peripheral edge having a different distance from the center of the rotation shaft is provided in the gap into which the part of the filter pieces enters. A filtration device, which is provided. 5. The filtering device according to claim 1, wherein the rotation speed of the filter located on the cake discharge direction side after the filtration is lower than the rotation speed of the other filter. Characteristic filtration device. 6. A filter in which a plurality of filter pieces are arranged with a gap in the direction of the rotation axis, a plurality of the filter pieces are arranged by projecting the filter pieces into a gap between the filter bodies adjacent to each other, and the filter body is rotated to dehydrate the filter. In the filtering method of discharging the filtered cake, a part of the plurality of filter pieces is arranged such that an outer peripheral edge is at a different distance from the center of the rotation axis, and the cake is pushed with the some filter pieces. A filtration method characterized by being transported.