JPH07241413A - Rotary drum type solid-liquid separator - Google Patents

Abstract

PURPOSE:To provide a rotary drum type solid-liquid separator in which a filter drum is prevented from being evacuated to become negative pressure. CONSTITUTION:The solid-liquid separator is provided with a filter drum 26 rotatably supported on a horizontal center axis 18 and covered with filter cloth 42 on the outer peripheral surface, a recovery hopper 78 arranged in the filter drum 26 and for recovering solid components caught by the filter cloth 42 together with a filtrate (washing water) jetted from a backup spray 76, a chamber 120 formed in the center axis 18 and for connecting the recovery hopper 78 and piping 124 outside the filter drum 26, and a vent pipe 24 extending from a portion of the center axis 18 placed outside the rotary drum 26 downwards and connected to the chamber 120.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary drum type solid-liquid separator for separating solid-liquid in raw water.

[0002]

2. Description of the Related Art A rotary-drum type solid-liquid separation device is equipped with a filter cloth mounted on a barrel and is horizontally arranged, and is configured to introduce raw water into the filter drum. The introduced raw water passes through the filter cloth of the rotating filtration drum and is discharged to the outside, and this filter cloth separates the solid liquid from the raw water. That is, the solid component in the raw water is captured on the inner surface of the filter cloth, and the raw water after the solid component is separated and removed, that is, the filtered water is discharged to the outside of the filtration drum.

Since the trapped solid components will clog the filter cloth as they are, it is necessary to remove the trapped solid components from the filter cloth in order to maintain the filtering performance of the filter cloth, that is, the filter drum. For this reason, when the filter cloth is exposed from the raw water to the outside, the filter cloth is sprayed with washing water to wash off the trapped solid components. After being collected together with the washing water in the inner collection hopper, it is discharged to the outside of the filtration drum. More specifically, the filtration drum is rotatably supported by the central shaft, and a passage that connects the recovery hopper and the pipe outside the filtration drum is formed in the central shaft.

[0004]

By the way, since the filter cloth of the filter drum has a low air permeability, the wash water collected together with the solid components in the collecting hopper is rapidly discharged from the collecting hopper through the passage and the pipe of the central shaft. Then, along with this discharge, a large amount of air in the filter drum is also discharged, and the inside of the filter drum may become negative pressure. When the pressure inside the filter drum becomes negative, the solid component captured on the filter cloth is peeled off from the filter cloth and dropped into raw water before being washed, and the recovery performance of the solid component is deteriorated.

The present invention has been made based on the above-mentioned circumstances, and an object thereof is to prevent negative pressure in the filtration drum and to stably maintain solid component recovery performance. It is to provide a rotary drum type solid-liquid separation device that can be used.

[0006]

In the rotary drum type solid-liquid separation device of the present invention, a filter drum having a filter medium mounted on a cylinder is rotatably supported by a hollow central shaft and is introduced inside the filter drum. The raw water is passed through the filter medium while rotating the filtration drum to separate the solid liquid in the raw water, and the solid components captured in the filter medium are washed off with the wash water and collected in the collection hopper.
The collected solid components are discharged together with the wash water from the recovery hopper to the outside of the filtration drum through the inside of the central shaft, and the ventilation means is provided for communicating the inside of the central shaft to the atmosphere.

[0007] Preferably, the ventilation means comprises a ventilation pipe extending upward from a portion of the central shaft located outside the filtration drum.

[0008]

According to the rotary drum type solid-liquid separation device described above,
When the collected solid components are discharged together with the washing water from the collection hopper to the outside of the filtration drum through the inside of the central shaft, outside air is introduced into the central shaft by the ventilation means.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a rotary drum type solid-liquid separator is schematically shown. This solid-liquid separation device is equipped with a processing tank 2, and inside this processing tank 2, a partition wall 4 and a discharge weir 6 are provided.
It is divided by. That is, the treatment tank 2 is the raw water tank 8,
It has a drainage tank 10 and a discharge tank 12.

A part of the partition wall 4 is formed by a seal plate 14, and this seal plate 14 has a communication port 16 at the center thereof. Inside the drainage tank 10, a hollow central shaft 1
8 are horizontally arranged, and the central shaft 18 extends from the filtered water tank 10 into the raw water tank 8 through the communication port 16 and is projected to the outside of the raw water tank 8 while maintaining liquid tightness. That is, a part of the outer wall of the raw water tank 8 is formed by the closing plate 20, and the central shaft 18 penetrates the closing plate 20 in a liquid-tight manner and is supported by the closing plate 20.

One end of the central shaft 18 is open, and this opening is closed by a seal disk 22 so that it can be opened and closed. The central shaft 18 located in the raw water tank 8 is provided with ventilation means, and the ventilation means has a ventilation pipe 24 extending upward from the central shaft 18. The ventilation pipe 24 has a lower end communicating with the center shaft 18 and an upper end opened.

Inside the drainage tank 10, a hollow filter drum 26 is provided.
The filter drum 26 is rotatably supported by the central shaft 18 via bearings 28 and 30 at both end surfaces thereof. As is apparent from FIG. 1, one bearing 28 projects toward the raw water tank 8 and the other bearing 30
Project toward the discharge weir 6. The other end of the central shaft 18 is a closed end and is positioned inside the bearing 30.

The bearing 30 is supported by a support frame 32,
The support frame 32 extends in a direction traversing the drainage tank 10 as viewed in FIG. 1, and both ends thereof are fixed to the inner wall of the drainage tank 10. A ring gear 34 is attached to the outer periphery of one end of the filtration drum 26, and a drive gear 36 rotated by a motor (not shown) is meshed with the ring gear 34. Therefore, the filter drum 26 is rotated in one direction by driving the motor.

Here, normally, the filtration drum 26 rotates integrally with the pair of bearings 28 and 30.
However, the bearings 28 and 30 can be moved in the axial direction of the central shaft 18 as needed. Filtration drum 26
Is provided with a grid-shaped frame, and this frame has a plurality of ring frames 38 arranged at predetermined intervals in the axial direction of the central shaft 18, and a plurality of reinforcing ribs 40 connecting the ring frames 38. It consists of Each reinforcing rib 40
Are arranged at equal intervals in the circumferential direction of the ring frame 38.

A filter cloth 42 as a filter medium is attached to the outside of the ring frame 38 and the reinforcing ribs 40, and the filter cloth 42 forms the peripheral surface of the filter drum 26. Here, as described in JP-A-58-207917 and JP-A-59-115720, the filter cloth 42 has a weft yarn in the width direction (axial direction of the central axis 18) and a single yarn. Woven or knitted base materials that use synthetic fibers having a diameter of 0.1 μm to 10 μm are used, and the weft threads of these base materials are directly raised in the longitudinal direction (rotational direction of the filtration drum 26) to have a thickness on the surface. A napped filter layer (not shown) made of ultrafine fibers of 0.1 μm to 10 μm is formed.

Since such a filter cloth 42 is raised in the longitudinal direction, the naps lie in that direction, but in use, the napped filter layer is inside the filter drum 26 and the naps are filtered. The drum 26 is mounted so as to be opposite to the rotating direction of the drum 26. The mounting of the filter cloth 42 will be specifically described. The filter cloth 42 is attached to the reinforcing ribs 40 as shown in FIGS. 2 and 3. FIG. 2 shows a connection structure between the intermediate region of the filter cloth 42 and the reinforcing ribs 40.
0s are connected to each other via hook-and-loop fasteners 44.
Here, one fastener sheet 44a of the hook-and-loop fastener 44
Is directly fixed to the reinforcing ribs 40, and the other fastener sheet 44b is fixed to the filter cloth 42 via the band 46 made of urethane resin.

FIG. 3 shows both ends of the filter cloth 42 and the reinforcing ribs 40.
The connection structure between and is shown. First, both ends of the filter cloth 42 are connected to each other via the band 48 made of urethane resin, and the pressing band 5 is pressed against the reinforcing rib 40.
It is fixed via 0 and a mounting bolt 52. Here, the width of the band 48 is wider than the width of the pressing band 50 and the reinforcing rib 40, as is clear from FIG.

As described above, if the intermediate region of the filter cloth 42 can be fixed to the reinforcing ribs 40 via the hook-and-loop fasteners 44, the filter cloth 42 can be easily attached to the frame. Further, the fixing of the filter cloth 42 to the reinforcing ribs 40 is not limited to the one using the hook-and-loop fastener 44, and the filter cloth 42 is fixed to the pair of rubber sheets 5 as shown in FIG.
4 and then these may be fixed to the reinforcing rib 40 via the pressing band 56 and the mounting bolt 58. The width of the rubber sheet 54 is wider than the width of the reinforcing ribs 40 and the pressing band 56, and both side edges thereof are bent in a direction of separating from the filter cloth 42.

When such a pressing band 56 is used, since the filter cloth 42 is sandwiched by the pair of rubber sheets 54, the edges of the pressing band 56 and the reinforcing ribs 40 are filtered while the filtration drum 26 is rotating. It does not bite into 42, and the life of the filter cloth 42 can be extended. Figure 4
The pair of rubber sheets 54 shown in FIG. 3 can be applied to the case of FIG.

On the other hand, for fixing the filter cloth 42 to the ring frame 38, a split type holding bar 60 is used as shown in FIG. These presser bars 60 are attached to the ring frame 38.
The filter cloth 42 is sandwiched between and and is fixed to the ring frame 38 via a mounting bolt (not shown). Filtration drum 26
One end surface, that is, the end surface 62 located on the partition wall 4 side
As is clear from FIG. 5, the central part has an open structure, and the other end surface 64 has a closed structure.

A ring seal 66 is arranged between one end surface of the filtration drum 26 and the seal plate 14 of the partition wall 4. The ring seal 66 connects the raw water tank 8 and the inside of the filtration drum 26. Thus, a raw water introduction passage for guiding raw water from the raw water tank 8 into the filtration drum 26 is formed. As shown in detail in FIG. 6, the ring seal 66 includes a mounting ring 68 protruding from the end surface 62 of the filtration drum 26, and the mounting ring 68 includes an annular lip seal 70. The base end of is fixed by a plurality of mounting bolts 72 and nuts 74. The tip side of the lip seal 70 is curved inward, and the tip portion thereof is in liquid-tight contact with the seal plate 14 of the partition wall 4. The lip seal 70 may be fixed by a band stopper (not shown).

Filter drum 26 as shown in FIG.
A backup spray 76 and a recovery hopper 78 that covers the backup spray 76 from below are arranged therein. Further, a backwash spray 80 is arranged outside the filtration drum 26, and the backwash spray 80 is
It is arranged so as to sandwich the filter cloth 42 and face the backup spray 76.

The backup spray 76 and the backwash spray 80 consist of a pipe member extending in the axial direction of the filtration drum 26 and a large number of nozzles attached to the pipe member at intervals in the longitudinal direction thereof. Nozzles for the backup spray 76 and the backwash spray 80 are designated by reference numerals 82 and 84. Here, as shown in FIG. 8, the injection axis of the nozzle 82 in the backup spray 76 is a predetermined distance from the injection axis of the nozzle 84 of the backwash spray 80 on the downstream side when viewed in the rotation direction of the filtration drum 26. It is preferably offset by a distance (eg about 5 mm).

The backup spray 76 is connected to the central shaft 18 via a pipe 86, and the pipe 86 is connected to one end of a pipe 90 via an internal passage 88 of the central shaft 18. The other end of this pipe 90 opens into filtered water in the filtered water tank 10 described later, and a supply pump 94 is provided in the middle thereof.
Has been inserted. This supply pump 94 is a drainage tank 10,
That is, it is arranged outside the processing tank 2.

On the other hand, the backwash spray 80 is connected to one end of a pipe 96, and the other end of the pipe 96 also opens below the surface of the filtered water in the filtered water tank 10, and a supply pump 98 is provided in the middle thereof. Has been inserted. Further, another cleaning spray 100 is arranged in the filtration drum 26, and the cleaning spray 100 is located downstream of the recovery hopper 78 when viewed in the rotation direction of the filtration drum 26 shown by the arrow A in FIG. 7. It is located in. Like the backup spray 76 and the backwash spray 80 described above, the cleaning spray 100 has a large number of nozzles 102 attached to its pipe member, and is connected to a pipe 86 extending from the backup spray 76 via a branch pipe 104. ing.

Y-type strainers 170 and 171 are provided on the discharge sides of the supply pumps 94 and 98, respectively.
These strainers 170 and 171 have nozzles 82 and 8 respectively.
Prevents clogging of 4,102. The strainers 170 and 171 may be arranged on the suction side of the supply pumps 94 and 98. Further, a chemical washing spray 106 is arranged outside the filtration drum 26, and the chemical washing spray 106 also has a large number of nozzles 108 on its pipe member.
Is attached. The chemical washing spray 106 is connected to a chemical liquid tank 112 via a pipe 110, and a supply pump 114 is inserted in the middle thereof. A chemical solution suitable for sterilizing the filter cloth 42 is stored in the chemical solution tank 112. The chemical washing spray 106 is positioned on the downstream side of the back washing spray 80 and in the area covered by the recovery hopper 78 as viewed in the rotation direction of the filtration drum 26. It should be noted that the ejection of the chemical solution from each nozzle 108 of the chemical washing spray 106 is performed at a desired time or periodically.

The recovery hopper 78 is fixed to the central shaft 18 and is also connected to the central shaft 18 via a pipe 116. More specifically, the inside of the central shaft 18 is divided into two chambers 120 and 122 by a partition wall 118.
16 is connected to one chamber 120. In addition, the above-mentioned internal passage 88 is provided from the inside of the partition wall 118 to the other chamber 122.
And is formed independently of the chamber 122.

A pipe 124 is connected to the chamber 120 of the central shaft 18, and the pipe 124 is connected to one end of the central shaft 18.
That is, as shown in FIG. 1, the raw water tank 8 extends downward from an end portion protruding to the outside and is connected to a recovery tank (not shown). On the other hand, the other chamber 12 of the central shaft 18
2, a discharge pipe 126 is connected, and this discharge pipe 126 extends downward from the central shaft 18 as is apparent from FIGS. 1 and 7, and the lower end thereof is the filtration drum 2
6 is open near the inner surface.

Further, an exhaust pipe 128 is connected to the other chamber 122 of the central shaft 18. This pipe 128 extends to the outside of the drainage tank 10 and has a structure for draining it to the outside of the solid-liquid separation device. A discharge pump 130 is inserted in the discharge pipe 128 outside the drainage tank 10. The discharge pipe 126, the chamber 122, the discharge pipe 128, and the discharge pump 130 described above constitute a means for discharging the solid component accumulated in the filtration drum 26, and therefore the chamber 122.
Is a discharge passage in the central shaft 18.

Next, the operation of the solid-liquid separation device described above will be described. First, the filtration drum 26 is in a state of being rotated at a constant speed through the meshing of the gears 34 and 36 by driving a motor (not shown). In this state, as is clear from FIG. 1, the raw water supplied to the raw water tank 8 of the treatment tank 2 passes through the raw water introducing passage formed by the annular lip seal 66 and the opening of the one end face 62 of the filtration drum 26.
It is introduced into the filtration drum 26. Here, the filtration drum 2
Since the one end surface 62 of 6 and the partition wall 4 are sealed by the lip seal 66, and the other end surface of the filtration drum 26 has a closed structure, the introduced raw water is filtered into the filtration drum 26.
It will be stored inside.

However, the filter cloth 42 of the filter drum 26
Has a water permeability, the raw water introduced therein passes through the filter cloth 42 and flows out into the drainage tank 10.
More specifically, the raw water in the filtration drum 26 receives potential energy based on the water level difference H (see FIG. 7) between the water level and the water level of the filtration tank 10 determined by the discharge weir 6, and the raw water is received. Only the liquid component passes through the filter cloth 42 and flows into the filtered water tank 10, and the solid component in the raw water is captured by the filter cloth 42. When the liquid level of the raw water component stored in the filtered water tank 10, that is, filtered water exceeds the discharge weir 6, the discharged water tank 12
To the outside of the solid-liquid separation device.

The solid component trapped on the filter cloth 42 reaches above the recovery hopper 78 as the filter drum 26 rotates.
Then, it is washed off by the filtered water ejected from each nozzle 84 of the backwash spray 80 and is collected by the recovery hopper 78. That is, while the filtration drum 26 is rotating, the supply pump 98 is driven, and the supply pump 98 uses the filtered water sucked from the filtering tank 10 as cleaning water and filters it from each nozzle 84 of the backwash spray 80. It is ejected toward the cloth 42.

On the other hand, at this time, the supply pump 94 is also driven, and the supply pump 94 uses the filtered water in the filtered water tank 10 as washing water through the pipe 90, the internal passage 88 of the central shaft 18 and the pipe 86. , Backup spray 7
6 to each of the nozzles 82, and ejected toward the filter cloth 42 from these nozzles 82. Further, the pipe 86 is the pipe 1
Since it is also connected to the cleaning spray 100 through 04, the filtered water is also jetted toward the filter cloth 42 from each nozzle 102 of this cleaning spray 100.

When the filtered water is jetted from each nozzle 84 of the backwash spray 80, the jetting pressure of the filtered water, together with the self-weight of the filter cloth 42, causes slack in the portion of the filter cloth 42 between the reinforcing ribs 40. I will let you. However, since the backup spray 76 faces the backwash spray 80 with the filter cloth 42 interposed therebetween, the nozzle 8 of the backup spray 76 is located.
The filtered water jetted from 2 prevents the filter cloth 42 from loosening as shown in FIG.

Therefore, the distances between the nozzles 84 of the backwash spray 80 and the filter cloth 42 passing therebelow are kept uniform, and the filtered water sprayed from the backwash spray 80 is applied to the outer surface of the filter cloth 42. To the inner surface of the filter cloth 42, the filtered water sprayed from the backup spray 76 can also be applied to the inner surface of the filter cloth 42. Here, the nozzle 82 of the backup spray 76 and the nozzle 84 of the backwash spray 80.
As described above, since the filter water is offset from each other in the rotation direction of the filter drum 26, the filtered water sprayed from the backup spray 76 onto the filter cloth 42 is the filtered water sprayed from the backwash spray 80 into the filter cloth 42. It does not cancel the impact force.

As described above, since the filter cloth 42 receives the jet of filtered water simultaneously on both the outer surface and the inner surface thereof, the filter cloth 42
Backwashing and surface washing are performed simultaneously, and the filter cloth 4
A slight vibration is caused in 2 to cause a so-called hand rubbing effect, and the solid component captured on the filter cloth 42 can be efficiently washed off to prevent the clogging. As a result,
Not only can the jet pressure and the jet amount of the filtered water required for the backwash spray 80 and the backup spray 76 be reduced, but the impact force that the filter cloth 42 receives due to the jet of filtered water is also reduced, and the durability of the filter cloth 42 is improved. Can be greatly improved.

Moreover, as described above, the filtered water is jetted toward the filter cloth 42 from each nozzle 102 of the cleaning spray 100 located on the downstream side of the recovery hopper 78 as viewed in the rotating direction of the filter drum 26. The filter cloth 42 is also washed with this filtered water. The solid component washed off from the filter cloth 42 is collected by the collection hopper 78, and the solid component is collected together with the filtered water from the collection hopper 78 through the pipe 116, the chamber 120 of the central shaft 18 and the pipe 124 into the collection tank. It is discharged toward.

From the recovery hopper 76 to the chamber 120 of the central shaft 18.
When the solid component is discharged together with the filtered water through the pipe, if the portion of the central shaft 18 on the chamber 120 side is a pipe whose both ends are closed, the inside of the filtering drum 26 becomes negative pressure as described above. There are cases. Further, when the solid component is clogged in the pipe 124 extending from the chamber 120 of the central shaft 18, the filtered water sprayed from the backup spray 76 cannot be discharged, and the inside of the chamber 120 is pressurized. .

However, as described above, the central axis 18
Since the ventilation pipe 24 extends upward from one end of the chamber, the inside of the chamber 120 of the central shaft 18 can be always communicated with the atmosphere. Therefore, even if the filtered water is discharged from the recovery hopper 78 through the chamber 120 of the central shaft 18 due to the communication with the atmosphere, the inside of the filtering drum 26 is not exhausted, and the inside of the filtering drum 26 becomes a negative pressure. It can be surely prevented. As a result, the solid component captured on the filter cloth 42 is not peeled off from the filter cloth 42 by the negative pressure action, and the solid component can be efficiently collected by the collection hopper 78 by washing the filter cloth 42, and the collection performance is stabilized. Can be maintained. Further, since the chamber 120 communicates with the atmosphere, the inside of the chamber 120 is not pressurized.

One end of the central shaft 18 is provided with a seal disk 22.
Since it can be opened and closed by means of the above, even if a solid component is clogged in the chamber 120 of the central shaft 18, if the seal disk 22 is removed, the cleaning brush can be removed from the one end opening of the central shaft 18 to the chamber 120. The inside of the chamber 120 can be easily removed by inserting the inside thereof, and the inside of the chamber 120 can be cleaned at the same time.

The filtration treatment of the raw water described above is similarly repeated in a plurality of solid-liquid separation devices, whereby the solid-liquid in the raw water is separated to a desired level. When the solid-liquid separation device is used for a long time, solid components in the raw water may gradually accumulate on the bottom of the filtration drum 26. The accumulation of such fixed components accelerates the clogging of the filter cloth 42, greatly lowers the filtering performance, and at the same time increases the rotational resistance of the filtering drum 26.

In such a situation, the drainage pump 13
0 is driven, and this drainage pump 130
The solid components accumulated on the bottom of the filtration drum 26 are sucked up from the lower end opening of the filter 26 together with the raw water, and the solid components are collected by the central shaft 18
It is discharged to the outside of the solid-liquid separation device through the chamber 122 and the discharge pipe 128. In this way, if the solid components deposited on the bottom of the filtration drum 26 are regularly discharged together with the raw water,
The filter cloth 42 can be prevented from being clogged, and its filtering performance can be stably maintained, and the rotation resistance of the filtering drum 26 does not increase.

The present invention is not limited to the above-described embodiment, but various modifications can be made. For example,
Referring to FIG. 9, a modification of the central shaft 18 is shown. The central shaft 18 of this modified example is provided with a screw conveyor 164 in its chamber 120, and this screw conveyor 164 extends from the lower end opening of the recovery hopper 78 to the pipe 1
It extends beyond 24 openings. The shaft of the screw conveyor 164 projects from one end of the central shaft 18 and is connected to the electric motor 166.

When the screw conveyor 164 is rotated by the electric motor 166, the central shaft 1 moves from the recovery hopper 78.
The solid component flowing into the chamber 120 of No. 8 together with the filtered water is forcibly carried to the opening of the pipe 124 by the screw conveyor 164, and then discharged through the pipe 124. When the screw conveyor 164 is used, the concentration of the solid component in the raw water is high and the solid component introduced into the chamber 120 of the central shaft 18 cannot be flowed only by the filtered water, or the fixed component becomes a slurry with the filtered water. Even in the case of the above, these can be reliably guided from the central axis 18 toward the pipe 124.

The screw conveyor 164 can be used together with the above-mentioned ventilation pipe 24, and instead of the screw conveyor 164, the partition wall 11 of the central shaft 18 is used.
8 may be provided with an air nozzle projecting toward the chamber 120, compressed air may be ejected from the air nozzle into the chamber 120, and the solid component or the slurry may be discharged by the flow of the compressed air.

Further, in the case of the above-mentioned filtration drum 26, the raw water introduction passage has the seal ring 66, that is,
Although the lip seal 70 is formed by the lip seal 70, the lip seal 70 is always in sliding contact with the seal plate 14 of the partition wall 4 during the rotation of the filtration drum 26, so that the wear cannot be avoided. For this reason, when using the solid-liquid separation device, it is necessary to replace the lip seal 70.

However, regarding this replacement work,
As described above, the filtration drum 26 itself can move on the bearings 28 and 30 in the axial direction thereof. Therefore, if the filtration drum 26 is moved within the range indicated by L in FIG. A space can be secured between the above and the lip seal 70, and the replacement work of the lip seal 70 can be performed using this space. Therefore, it is not necessary to take out the entire filtration drum 26 to the outside of the processing tank 2 to replace the lip seal 70, and the lip seal 70 can be easily replaced.

The solid-liquid separation device of the present invention can be used for various purposes. For example, it can be used for a solid-liquid separation device for lake water or river water. In addition, so-called suspended sludge, such as surplus sludge produced as a by-product in the activated sludge treatment device, and so-called fixed sludge discharged from the biofilm treatment device, such as sludge, scum, and flocs produced by wastewater treatment. It can be used when filtering, concentrating washing water, sludge, etc. Furthermore, it can be used for solid-liquid separation in the manufacturing process of paper pulp, food, liquor, miso, etc., and recovery of valuables in chemical processes.

[0049]

As described above, in the rotary drum type solid-liquid separation device of the present invention, the hollow central shaft of the filtration drum is communicated with the outside air by the aeration means, so that it is recovered in the recovery hopper. Even if the wash water is discharged through the central shaft, the inside of the filter drum is not discharged and the negative pressure is not generated.
Therefore, the solid component captured on the filter material of the filtration drum can be reliably collected in the collection hopper, and the collection performance can be stably maintained.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing a rotary drum type solid-liquid separation device according to an embodiment.

2 is a cross-sectional view showing the connection of the center portion of the filter cloth to the reinforcing ribs of the filter drum of FIG.

FIG. 3 is a cross-sectional view showing the connection of both ends of the filter cloth to the reinforcing ribs.

FIG. 4 is a cross-sectional view showing another method of connecting the center portion of the filter cloth to the reinforcing ribs.

FIG. 5 is a schematic perspective view showing a filtration drum.

FIG. 6 is a sectional view showing a part of a ring seal between a filtration drum and a partition wall.

FIG. 7 is a diagram showing a supply system of filtered water to a backwash spray and a backup spray.

FIG. 8 is a diagram showing an action of filtered water sprayed from a backup spray.

FIG. 9 is a cross-sectional view showing a screw conveyor housed in a chamber of a central shaft.

[Explanation of symbols]

 2 treatment tank 4 partition wall 6 discharge weir 8 raw water tank 10 filtered water tank 12 discharge tank 14 seal plate 16 communication port 18 central shaft 20 blocking plate 22 seal disk 24 ventilation pipe 26 filtration drum 28, 30 bearing 32 support frame 34 ring gear 36 drive gear 38 Ring frame 40 Reinforcement rib 42 Filter cloth (filter material) 44 Face fastener 46,48 Band 50,56 Holding band 52,58 Mounting bolt 54 Rubber sheet 60 Holding bar 62,64 End surface 66 Ring seal 68 Mounting ring 70 Lip seal 72 Mounting Bolt 74 Nut 76 Backup spray 78 Recovery hopper 80 Backwash spray 82, 84, 102, 108 Nozzle 86, 90, 96, 110, 116, 124 Piping 88 Internal passage 94, 98, 114 Supply pump 100 Wash spray 104岐配 pipe 112 liquid tank 118 partition walls 120, 122 chamber 126 discharging pipe 128 discharging pipe 130 discharging pump 170 and 171 Y-type strainer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B01D 33/58

Claims (2)

[Claims] 1. A filter drum having a filter medium mounted on a barrel is rotatably supported on a hollow central shaft, and raw water introduced into the filter drum is passed through the filter drum while rotating the filter drum. To separate the solid-liquid in the raw water, the solid components captured in the filter medium are washed off with washing water and collected in a collection hopper, and the collected solid components are passed through the central shaft from the collection hopper together with the washing water. In the solid-liquid separation device for discharging to the outside of the filtration drum, a rotating drum type solid-liquid separation device is provided, which is provided with ventilation means for communicating the inside of the central shaft with the atmosphere. 2. The rotating drum type solid-liquid separation device according to claim 1, wherein the ventilation means includes a ventilation pipe extending upward from a central axis portion located outside the filtration drum. apparatus.