JP4553287B2 - Solid-liquid separator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a membrane filtration type solid-liquid separation apparatus used for sludge concentration treatment in a sewage treatment plant or a water purification plant.
[0002]
[Prior art]
As this type of solid-liquid separator, the one shown in FIG. 6 is known (see Japanese Patent Laid-Open No. 2001-47100).
[0003]
In the solid-liquid separator 80 shown in this figure, the interior of the solid-liquid separation tank 81 filters the lower chamber (first chamber) 83 into which raw water is introduced and the solid content (sludge) by the partition wall 82 arranged horizontally. And an upper chamber (second chamber) 84 for collecting the filtered water obtained in this manner. The partition wall 82 has a large number of water passage openings 82a, and a filter 90 is attached to each opening 82a. The filter 90 is formed of a membrane tube 91 having a shape depending on the first chamber 83 side.
[0004]
The lower chamber 83 is provided with a raw water introduction port 85, and a raw water introduction pipe 86 is connected to the raw water introduction port 85. In addition, a sludge discharge port 94 is provided at the bottom of the lower chamber 83. The upper chamber 84 is provided with a filtered water discharge port 87, and a filtered water discharge pipe 88 is connected to the filtered water discharge port 87. The filtered water discharge pipe 88 is connected to a pressurized air pipe 89 for introducing pressurized air into the upper chamber 84 as necessary.
[0005]
In order to perform solid-liquid separation of raw water with this apparatus 80, raw water is introduced into the lower chamber 83 from the raw water introduction pipe 86 at a predetermined pressure. If it does so, the solid substance in raw | natural water will be capture | acquired by the filter 90, filtered water will flow into the upper chamber 84, and will be discharged | emitted from the filtered water liquid discharge port 87 outside. As the solid-liquid separation process continues, the trapped solid matter accumulates on the filter 90, and the pressure loss when the filtrate passes through the filter 90 gradually increases.
[0006]
Then, when the pressure loss reaches a predetermined magnitude, the filter 90 is backwashed. That is, first, the open / close valve (not shown) of the raw water introduction pipe 86 is closed to stop the introduction of the raw water, and then the sludge accumulated in the lower chamber 83 is discharged, and then the open / close valve of the filtered water discharge pipe 88 ( With the closed state (not shown), pressurized air is introduced from the pressurized air pipe 89 into the upper chamber 84, backwashing pressure is applied to the filter 90, and solid matter adhering to the filter 90 is dropped into the lower chamber 83. Let In this case, an air pressure can be applied to the filter 90 as a backwash pressure, or a hydraulic pressure can be applied.
[0007]
[Problems to be solved by the invention]
By the way, in the conventional solid-liquid separation device 80, since the backwashing pressure is simultaneously applied to all the many filters 90, the washing pressure for each filter 90 is lowered, and the solid matter deposited on the film surface is removed. There is a problem that the dropping efficiency (cleaning efficiency) is deteriorated, and as a result, high solid-liquid separation efficiency cannot be maintained.
[0008]
In view of the above circumstances, an object of the present invention is to provide a solid-liquid separation device that can enhance the cleaning effect during backwashing and maintain high processing efficiency at all times.
[0009]
[Means for Solving the Problems]
The solid-liquid separation device according to the first aspect of the present invention is divided into a lower chamber for introducing the raw water and an upper chamber for collecting the filtered water obtained by filtering the raw water by the partition walls arranged horizontally inside the solid-liquid separation tank. A solid-liquid separation device that captures solids contained in raw water by the filter by partitioning and attaching a filter to each of a large number of openings formed in the partition and passing water from the lower chamber toward the upper chamber in the the opening fitted with a respective filter, together with the allow the flow of water toward the upper chamber from the lower chamber, and provided with a check valve for preventing the flow of water toward the lower chamber from the upper chamber, When the filter is backwashed, the check valve is divided into a plurality of groups each including at least one check valve, and a forcible opening mechanism for forcibly opening each group in order is provided . Of the opening formed By fixing the upper end to the edge, the membrane cylinder constituting the filter or the cylinder filled with the filter medium in the cylindrical frame is suspended below the partition wall, and the check valve is closed from above. And a cover plate that can be opened and closed in the vertical direction biased in the closing direction, and as the forcible opening mechanism, a lever provided on the cover plate is moved as it passes over the cover plate in order and passes. Thus, an arm for forcibly opening the cover plate against the urging force is provided .
[0010]
When performing solid-liquid separation with this solid-liquid separator, raw water is introduced into the first chamber at a predetermined pressure. If it does so, the reverse heart valve provided in each opening will open, and raw | natural water will be filtered through each filter. On the other hand, when performing backwashing of the filter, pressure is applied so that water (in principle, even air instead of water) flows from the second chamber side to the first chamber side. The pressure can be applied by simply opening the first chamber (opening the outflow passage valve), applying negative pressure with the suction pump to the first chamber, and positive with the pressure pump on the second chamber. There is a method of applying pressure.
[0011]
When pressure is applied in such a way, the check valve is closed in the direction of closing, so many check valves remain closed, but the check valves are forcibly opened in turn for each group by the forced release mechanism. By doing so, the backwashing pressure can be applied intensively only to the opened portion of the filter. That is, the backwash pressure can be applied only to a part of the filters instead of applying the backwash pressure to all the filters simultaneously. Accordingly, the backwash pressure for each filter can be set high, and the washing efficiency is increased. Since the forcible opening mechanism opens the check valves in order for each group, all the filters can be washed over time.
[0012]
As a means for urging the cover plate in the closing direction, the weight of the cover plate may be employed, or a spring may be employed.
[0013]
Furthermore , when raw water of a predetermined pressure is introduced into the lower chamber for solid-liquid separation, the cover plate (check valve) provided at each opening is lifted and opened by the water pressure, and the raw water passes through each filter (membrane cylinder). Filtered. On the other hand, when the arm is moved on each cover plate during backwashing, each time the arm passes over each cover plate, the lever provided on the cover plate below it is moved by interference with the arm. This forcibly releases only the lower cover plate of the arm. And a high washing | cleaning efficiency is achieved because backwashing pressure concentrates on the filter of the open part, and applies.
[0014]
The solid-liquid separation device according to a second aspect of the present invention is the solid-liquid separation device according to the first aspect , wherein the arm is configured to be drivable by a drive mechanism of a sludge scraping scraper, and a position when the lever is operated and a position when the lever is not operated It is characterized in that it can be selectively switched.
[0015]
In this solid-liquid separation device, the sludge scraper drive mechanism is used to drive the arm, so that the device can be simplified. However, if the arm is driven by the scraper drive mechanism, the arm may inadvertently interfere with the lever of the lid plate when the scraper is driven. Therefore, when it is necessary to operate the lever, the position of the arm is switched to a position where the lever can be operated, and when there is no need to operate the lever, the position of the arm cannot be operated, that is, an upper position where it does not interfere with the lever. Evacuate. This eliminates the possibility of inadvertently operating the lever when driving the scraper.
[0016]
Solid-liquid separating apparatus according to claim 3, in claim 1 or 2, the plan view shape of the solid-liquid separation tank is circular, said arms, arranged in a radial direction of the solid-liquid separation tank, and the circumferential direction The lid plate is forcibly opened in order by rotating along the axis.
[0017]
A solid-liquid separation device according to a fourth aspect of the present invention is the solid-liquid separation device according to the first or second aspect, wherein the solid-liquid separation tank has a rectangular shape in plan view, and the arms are arranged in a direction crossing between opposing sides of the solid-liquid separation tank. In addition, the lid plate is forcibly opened in order by linearly moving in a direction intersecting with itself.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1A and 1B are views showing a state of the solid-liquid separation device of the embodiment at the time of a solid-liquid separation process, where FIG. 1A is a cross-sectional view, and FIG. FIGS. 2A and 2B are views showing a state of the solid-liquid separator when the filter is backwashed, in which FIG. 2A is a top view and FIG. 2B is a cross-sectional view.
FIG. 3 is an enlarged cross-sectional view showing the state of the filter portion during solid-liquid separation, and FIG. 4 is an enlarged cross-sectional view showing the state of the filter portion during backwashing.
[0019]
As shown in FIGS. 1 (a), 2 (a), and 2 (b), this solid-liquid separation device 10 is for sludge concentration, the shape of the plan view is circular, the bottom is conical, and the bottom is centered. Is provided with a solid-liquid separation tank (sludge concentration tank) 11 in which a waste mud pit 20 is formed. The interior space of the solid-liquid separation tank 11 is collected by a horizontally-divided partition wall 12 to collect a lower chamber (first chamber) 13 into which raw water is introduced and filtered water obtained by filtering the raw water to overflow outside. It is partitioned into an upper chamber (second chamber) 14.
[0020]
A raw water introduction port 15 is provided in a side portion of the lower chamber 13 (or the mud pit 20 is acceptable), and a raw water introduction pipe 17 is connected to the raw water introduction port 15 via an opening / closing valve 16. Further, a sludge discharge port 21 is provided in the sludge pit 20 at the bottom of the lower chamber 13 , and a suction pump 23 is connected to the sludge discharge port 21 via a sludge discharge pipe 22. The upper chamber 14 is provided with a filtered water discharge port 18 for overflowing the filtered water, and a filtered water discharge pipe 19 is connected to the filtered water discharge port 18.
[0021]
A rotary sludge scraping scraper 25 is provided at the conical bottom of the lower chamber 13. The sludge scraping scraper 25 is connected to the lower end of a drive shaft 26 disposed perpendicularly to the center of the solid-liquid separation tank 11, and is viewed from above by driving a motor 27 connected to the upper end of the drive shaft 26. Then, the sludge accumulated in the bottom surface of the lower chamber 13 can be collected in the central waste mud pit 20 by rotating clockwise (in the direction of arrow C in FIG. 2A ).
[0022]
In the partition wall 12 that divides the lower chamber 13 and the upper chamber 14, a large number of water passage openings 12a are arranged along the circumferential direction of the solid-liquid separation tank 11, and a filter 30 is provided in each opening 12a. It is attached. Each filter 30 is provided with a membrane cylinder 31 that hangs down to the lower chamber 13 side with its upper end fixed to the peripheral edge of the opening 12a, as shown in an enlarged view in FIGS. ing.
[0023]
Each opening 12a to which the filter 30 is attached is provided with a cover plate 32 as a check valve. Each cover plate 32 closes the opening 12a from the upper side and can be opened and closed in the up-down direction biased downward, which is the closing direction, so that water flows from the lower chamber 13 to the upper chamber 14 [FIG. 1 (a), and a function as a check valve that prevents the flow of water from the upper chamber 14 toward the lower chamber 13. In this case, as a means for urging the cover plate 32 in the closing direction, the weight of the cover plate 32 is employed, but a spring may be employed.
[0024]
Each cover plate 32 is rotatably connected to the partition wall 12 by a hinge 34 at an end portion on the same side along the circumferential direction of the solid-liquid separation tank 11 (end portion in the rotation direction of the sludge scraping scraper 25). A lever 33 protruding upward is integrally provided at an end portion of the side supported by the hinge 34. The lid plate 32 can be forcibly opened by tilting the lever 33. In addition, if the cover plate 32 is excessively rotated to the open side, there is a possibility that the cover plate 32 may not return to the original closed position due to its own weight. Therefore, a stopper 35 that defines a rotation limit is provided at an appropriate position.
[0025]
Thus, as shown in FIG. 2A, a large number of cover plates 32 are arranged on the upper surface of the partition wall 12 with the levers 33 facing in a constant circumferential direction. On the upper side, an arm 42 is provided as a forced opening mechanism for forcibly opening a part of the cover plates 32 for each group when the filter 30 is backwashed. The number of the cover plates 32 opened at one time may be one or more. In this case, since the arms 42 are provided along the radius of the solid-liquid separation tank 11, the cover plates 32 arranged on the same radius are Belong to a group that is released at once.
[0026]
The arm 42 is connected to the drive shaft 26 of the sludge scraping scraper 25, and is driven to rotate in a certain direction (the same direction as the scraper 25) by the rotation of the drive shaft 26, and sequentially passes over the lid plate 32. When passing, as shown in FIG. 4, the lever 33 provided on the cover plate 32 interferes with the lever 33 so that the cover plate 32 can be forcibly opened against the urging force. It has become. In this case, after the arm 42 passes the lever 33, the cover plate 32 returns to the closed position by its own weight.
[0027]
Further, in this embodiment, the arm 42 is connected to the drive shaft 26 by the pin 41 so as to be rotatable in the vertical direction, and the lever 33 is moved from the horizontal position (position of FIG. 2B) when the lever 33 is operated. Is supported so that the position can be changed over to a slightly lifted position (the position shown in FIG. 1A) when not operated. This is to prevent the arm 42 from inadvertently hitting the lever 33 when the scraper 25 is rotated at a time other than backwashing.
[0028]
Next, the operation will be described.
When the solid-liquid separation process is performed by the solid-liquid separator 10, raw water having a predetermined pressure is introduced into the lower chamber 13 through the raw water introduction pipe 17. Then, as shown in FIGS. 1B and 3, the lid plate 32 provided in each opening 12 a of the partition wall 12 is lifted by water pressure and opened, and passes through the filter 30 (membrane cylinder 31) as indicated by an arrow A. The raw water is filtered, and the filtered water is sent to the next process through the filtered water discharge pipe 19. At that time, the sludge scraping scraper 25 is rotated while the arm 42 is retracted upward, so that the sludge accumulated at the bottom of the lower chamber 13 is collected in the drainage pit 20.
[0029]
When the solid-liquid separation process is completed, the on / off valve 16 of the raw water introduction pipe 17 is closed and the suction pump 23 is driven to discharge the sludge collected in the waste mud pit 20 to the outside. At this time, by applying a negative pressure (suction pressure) to the lower chamber 13, all the cover plates 32 try to close. However, if all the cover plates 32 are closed, the sludge cannot be discharged, so the arm 42. Is lowered to a horizontal position, and the cover plate 32 of one of the filters 30 is opened.
[0030]
And by continuing said suction operation | movement, the sludge which sank in the bottom part of the solid-liquid separation tank 11 is discharged | emitted with residual water outside. At this time, while continuing the suction, the forcible release arm 42 is rotated and applied to the levers 33 of the lid plates 32 in order. Then, as shown in FIG. 4, only the cover plate 32 where the lever 33 hits the arm 42 is opened, and the permeated water on the upper chamber 14 side is subjected to the solid-liquid separation step as shown by the arrow B by the action of the suction pump. Passes through the membrane cylinder 31 in the opposite direction, and the solid content N adhering to the outer surface of the membrane cylinder 31 is washed.
[0031]
Thus, by rotating the arm 42, only the cover plate 32 of the portion through which the arm 42 passes can be opened, so that the backwash pressure can be concentrated only on the filter 30 of the opened portion. it can. That is, the backwash pressure can be applied only to a part of the filters 30 instead of applying the backwash pressure to all the filters 30 simultaneously. Therefore, the backwashing pressure for each filter 30 can be set high, and the washing efficiency is increased. When the arm 42 is rotated once, all the cover plates 32 can be opened in order, so that all the filters 30 can be washed over time. Further, in this solid-liquid separation device 10, since the drive mechanism (motor 27) of the sludge scraping scraper 25 is used as the rotation drive mechanism of the arm 42, the apparatus can be simplified.
[0032]
In the embodiment described above, the solid-liquid separation tank 11 is circular. However, a rectangular (rectangular) solid-liquid separation tank 51 may be used as in the solid-liquid separation apparatus 50 shown in FIG.
In that case, the arm 62 forcibly opening the cover plate 32 is arranged in a direction crossing between the opposing long sides of the solid-liquid separation tank 51, and the arm 62 is linearly moved in a direction (longitudinal direction) intersecting itself. By setting so as to do, it is possible to forcibly open the cover plate 32 in order.
[0033]
Moreover, in the above-mentioned embodiment, although the example which employ | adopted the film cylinder as a filter was hung up, the other form is also considered. For example, this filter may be one in which a filter medium (sand, granular filter medium such as anthracite, or floating filter medium) is filled inside a cylindrical frame body. Moreover, in the above-mentioned embodiment, the example provided with the pump which attracts | sucks and transfers sludge was given. According to this, although the backwash pressure can be increased by the action of the suction pump, this suction pump is not always necessary. That is, when the structure is such that the sludge is discharged by opening and closing the valve, it is possible to generate the backwash pressure by opening the valve even if there is no suction pump. Furthermore, although the said embodiment is an example which applied this invention to the sludge concentration tank, this invention is applied to other various sedimentation basins (first sedimentation basin, final sedimentation basin, rainwater sedimentation basin, coagulation sedimentation basin). Application as an alternative to filtration equipment is also possible.
[0034]
【The invention's effect】
As described above, according to the first aspect of the present invention, a check valve is provided for each filter, and the backwash pressure is concentrated only on a part of the filters forcibly opening the check valve at the time of filter backwashing. In this way, since the check valves to be opened are sequentially moved, the backwash pressure for each filter can be set high, and the washing effect can be enhanced. Therefore, high solid-liquid separation efficiency can always be maintained.
[0035]
Since the check valve is formed of a cover plate and an arm is provided as a mechanism for forcibly opening the cover plate during backwashing, the above-described effects can be obtained with only a mechanical structure. According to the invention of claim 2 , since the arm is driven by the drive mechanism of the sludge scraping scraper, the apparatus can be simplified. In addition, since the position of the arm can be switched, the arm does not interfere with the operation when the scraper is driven.
[0036]
According to the invention of claim 3 , the above-mentioned effect can be obtained in a circular solid-liquid separation tank. According to the invention of claim 4 , the above-described effect can be obtained in a rectangular solid-liquid separation tank. Can do.
[Brief description of the drawings]
1A and 1B are views showing a state of a solid-liquid separation process of a solid-liquid separation apparatus according to an embodiment of the present invention, in which FIG. 1A is a cross-sectional view, and FIG.
FIGS. 2A and 2B are diagrams showing a state of the solid-liquid separation apparatus during backwashing of the filter, wherein FIG. 2A is a top view and FIG. 2B is a cross-sectional view.
FIG. 3 is an enlarged cross-sectional view showing a state of a filter portion during solid-liquid separation.
FIG. 4 is an enlarged cross-sectional view showing a state in which the filter portion is backwashed.
FIG. 5 is a top view showing a schematic configuration of another embodiment of the present invention.
FIG. 6 is a cross-sectional view showing an example of a conventional solid-liquid separator.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Solid-liquid separator 11 Solid-liquid separation tank 12 Partition 12a Opening 13 Lower chamber (1st chamber)
14 Upper room (second room)
25 Sludge scraping scraper 26 Drive shaft 27 Motor (drive mechanism)
23 Suction pump 30 Filter 31 Membrane cylinder 32 Cover plate (check valve)
33 Lever 42 Arm

Claims (4)

A partition wall horizontally arranged inside the solid-liquid separation tank is divided into a lower chamber for introducing the raw water and an upper chamber for collecting the filtered water obtained by filtering the raw water, and a plurality of openings formed in the partition wall. In the solid-liquid separation device that captures the solid content contained in the raw water by the filter by attaching each filter and passing water from the lower chamber toward the upper chamber ,
Provided with a check valve that allows the flow of water from the lower chamber to the upper chamber and prevents the flow of water from the upper chamber to the lower chamber in the opening to which each filter is attached,
Dividing all the check valves at the time of backwashing the filter into a plurality of groups including at least one check valve, and providing a forced opening mechanism for forcibly opening in order for each group ;
By fixing the upper end to the peripheral edge of the opening formed in the partition wall, the membrane cylinder constituting the filter, or the cylinder body filled with the filter medium in the cylindrical frame, is suspended below the partition wall, and the check valve is In addition, the lid is configured to be a vertically openable and closable lid that closes the opening from above and is urged in the closing direction, and as the forcible opening mechanism, a lid is passed when passing over and sequentially passing over the lid. A solid-liquid separator comprising an arm for forcibly opening a cover plate against an urging force by moving a lever provided on the plate . Said arm, while drivable constituted by sludge scraper scraper drive mechanism, to claim 1, characterized in that arranged to be selectively switched between a position at which the position and no operation is performed at the time of operating the lever The solid-liquid separator described. The solid-liquid separation tank has a circular shape in plan view, the arm is arranged in the radial direction of the solid-liquid separation tank, and the lid plate is forcibly opened in turn by rotating along the circumferential direction. The solid-liquid separation device according to claim 1 or 2 , wherein the solid-liquid separation device is configured to be made to be allowed to operate. The solid-liquid separation tank has a rectangular shape in plan view, and the arms are arranged in a direction crossing between opposite sides of the solid-liquid separation tank, and are moved in a straight line in a direction intersecting with the arm in order. solid-liquid separating apparatus according to claim 1 or 2, characterized by being configured as to forcibly open the plate.

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