JP2020185552A - Filter cloth cleaning method of filter press - Google Patents

Abstract

To provide a filter cloth cleaning method of a filter press which can clean an entire surface of a filter cloth with high detergency even if a filter press cleans the filter cloth in a filter chamber.SOLUTION: A filter cloth cleaning method of a filter press which cleans a filter cloth 21 disposed in a filter chamber formed between filter plates 19 includes: a step in which the filter plates 19 are closed to form the filter chamber between the filter plates 19; a step in which a cleaning fluid and an impact body 8 are supplied from an undiluted solution supply hole 24 to the filter chamber; a step in which air is introduced from a communication port 26c to stir the filter chamber; a step in which the filter plates 19 are opened to discharge the cleaning fluid and the impact body 8 from the filter chamber; and a step in which the cleaning fluid and the impact body 8 are separated to recover the impact body 8.SELECTED DRAWING: Figure 7

Description

The present invention is a filter press cleaning method for a filter press that cleans a filter cloth arranged in a filter chamber formed between filter plates. Regarding the filter cloth cleaning method.

Conventionally, the filter cloth cleaning method of the filter press is to open the filter plate in order to discharge the dehydrated cake, then maintain the open plate state and spray cleaning water on the filtration surface of the filter cloth to eject the dehydrated cake attached to the filter cloth. A cleaning method is used to peel off the cake.
In addition, as in Patent Document 1, after discharging the dehydrated cake, the filter plate is closed, the filtration chamber in which the filter cloth is arranged is filled with a cleaning liquid, and compressed air is injected to dewater the dehydrated cake from the filter cloth. A cleaning method is used to peel off the air.

Jikken 04-54802 Gazette

A cleaning method in which cleaning water is sprayed onto the filter cloth with the filter plate open, as in a conventional filter press, requires a cleaning device for spraying the cleaning water. To clean the entire surface of the filter cloth, the filter cloth or cleaning is required. The equipment had to be moved, which was complicated and expensive.
Further, as in Patent Document 1, after the filtration chamber is filled with washing water, the washing power is insufficient to wash the filter cloth only with compressed air, and sludge clogged in the filter cloth can be peeled off. There wasn't. Further, in Patent Document 1, since compressed air is injected from the back of the filtration surface, there is a problem that the detergency to the filtration surface side is low, and since compressed air is injected from the upper part of the filtration chamber, the detergency of compressed air is injected from the lower part of the filtration chamber. There was also the problem that it was low.
The present invention provides a filter cloth cleaning method for a filter press capable of cleaning the entire surface of a filter cloth in a filtration chamber with high detergency.

In the filter cloth cleaning method of the filter press for cleaning the filter cloth arranged in the filtration chamber formed between the plurality of filter plates, a step of closing the plurality of filter plates to form a filtration chamber between the filter plates and a filtration chamber It includes a step of supplying the cleaning liquid and the impact body to the filter chamber, a step of stirring the filtration chamber, a step of discharging the cleaning liquid and the impact body from the filtration chamber, and a step of separating the cleaning liquid and the impact body and collecting the impact body. Therefore, a high filter cloth cleaning ability can be obtained.

In the step of stirring the filtration chamber, running water can be generated and stirred in the filtration chamber by supplying the cleaning liquid to the filtration chamber and discharging the cleaning liquid from the filtration chamber.

In the step of stirring the filtration chamber, air can be agitated by supplying air to the filtration chamber and discharging air from the filtration chamber.

In the present invention, when cleaning the filter cloth of the filter press, the impact body is supplied to the filtration chamber together with the cleaning liquid, and the impact body floats by injecting air, and the impact body collides with the filter cloth to obtain high cleaning power. Be done. By this filter cloth cleaning, clogging of the filter cloth can be eliminated, deterioration of filtration performance can be prevented, and the life of the filter cloth can be extended.
In addition, complicated cleaning equipment is not required, and equipment costs and maintenance costs can be reduced.

It is a schematic block diagram of the filter press which concerns on this invention. Similarly, it is a side view of the filter press. Similarly, it is a front view of the filter plate of the filter press. Similarly, it is a rear view of the filter plate of the filter press. Similarly, it is sectional drawing of the filtration chamber during the dehydration operation of a filter press. Similarly, it is sectional drawing of the filtration chamber which supplies an impact body. Similarly, it is a cross-sectional view of a filtration chamber during filter cloth cleaning of a filter press.

FIG. 1 is a schematic configuration diagram of a filter press according to the present invention.
The present invention is a filter press that supplies a cleaning liquid to a filtration chamber to clean a filter cloth, and supplies an impact body that floats in the filtration chamber together with the cleaning liquid, and causes the impact body to collide with the filter cloth for cleaning. This is a cloth cleaning method.

The filter press 1 connects the stock solution storage tank 2 with the stock solution supply pipe 3, and supplies the sludge from the stock solution storage tank 2 to the filter press 1 by the mud supply pump 4 provided in the stock solution supply pipe 3.
The cleaning liquid storage tank 5 for storing the cleaning liquid and the stock solution supply pipe 3 are connected by a cleaning liquid supply pipe 6, and the cleaning liquid supply pipe 6 is provided with a cleaning liquid pump 7.
The impact body tank 9 for storing the impact body 8 and the cleaning liquid supply pipe 6 are connected by the impact body supply pipe 10, and the impact body supply pipe 10 is provided with an on-off valve 11.
The impact body supply pipe 10 is connected to the cleaning liquid supply pipe 6 in front of the cleaning liquid pump 7, and when the on-off valve 11 is opened, the cleaning liquid and the impact body 8 are supplied to the filter press 1.

The drain pipe 12, the air supply pipe 13, and the exhaust pipe 14 are connected to the filter press 1. The drain pipe 12 discharges the filtrate filtered by the filter press 1. When cleaning the filter cloth, the cleaning liquid is returned from the drain pipe 12 to the cleaning liquid storage tank 5 for reuse. The air supply pipe 13 connects the blower 15 to supply air to the filter press 1, and the exhaust pipe 14 discharges the air supplied by the blower 15 to the outside of the machine.
A recovery tank 16 for storing the cleaning liquid discharged from the filter press 1 and the colliding body 8 after cleaning the filter cloth is provided below the filter press 1, and the colliding body 8 is collected from the collecting tank 16 and returned to the impact body tank 9. ..

FIG. 2 is a side view of the filter press according to the present invention.
The filter press 1 of the present invention includes a frame 17 arranged on the left and right sides, a pair of guide rails 18 and 18 supported between the frames 17 and 17, and a plurality of filter plates 19 movably arranged side by side on the guide rail 18. It also has an opening / closing device 20 that opens / closes the filter plate 19.
A filter cloth 21 is stretched on both sides of the filter plate 19. When the plurality of filter plates 19 are closed, a filtration chamber 22 in which a filter cloth 21 is stretched is formed, and a stock solution is supplied between the filter cloths 21 and 21 of the filtration chamber 22 for dehydration.
Further, a stock solution supply pipe 3 for supplying the stock solution and the cleaning liquid and the impact body 8 and an exhaust pipe 14 for discharging air from the filtration chamber 22 are connected to the upper part of the filtration chamber 22. Further, a drain pipe 12 for discharging the filtrate and the cleaning liquid and an air supply pipe 13 for supplying air to the filtration chamber 22 are connected to the lower part of the filtration chamber 22.

FIG. 3 is a front view of the filter plate of the filter press according to the present invention.
A concave filter bed 23 is formed in the central portion of the filter plate 19, and a filter cloth 21 is stretched on the filter bed 23.
An undiluted solution supply hole 24 communicating with the undiluted solution supply pipe 3 and an exhaust hole 25 for discharging the air used for cleaning the filter cloth 21 are opened in the upper part of the filtration bed 23, and the exhaust hole 25 is one side surface of the filter plate 19 (FIG. 3). It penetrates through the communication port 26a provided in (right).
A water passage hole 27 for the filtrate and the cleaning liquid is opened in the lower part of the filtration floor 23, and the water passage hole 27 penetrates through the communication port 26b provided on the other side surface (left in FIG. 3) of the filter plate 19.

FIG. 4 is a rear view of the filter plate of the filter press according to the present invention.
Similar to the front surface of the filter plate 19, the filter bed 23 is formed in the central portion, and the filter cloth 21 is stretched on the filter bed 23. A stock solution supply hole 24 opens in the upper part of the filtration bed 23.
An air supply hole 28 for supplying air used for cleaning the filter cloth 21 is opened in the lower part of the filtration floor 23, and the air supply hole 28 penetrates through a communication port 26c provided on one side surface (left in FIG. 4) of the filter plate 19.

As shown in FIGS. 3 and 4, a stock solution supply hole 24 opens in the upper part of the filter plate 19. The stock solution supply hole 24 is connected to the stock solution supply pipe 3, and when the plate is closed, the stock solution supply holes 24 of the plurality of filter plates 19 communicate with each other to serve as a passage for supplying the stock solution to the filtration chamber 22.
Further, the plurality of filter plates 19 are provided with communication ports 26a, 26b and 26c, respectively, and when the plates are closed, the communication ports 26a, 26b and 26c of the filter plates 19 communicate with each other.
During the filter cloth cleaning, the cleaning liquid is supplied from the stock solution supply hole 24, the cleaning liquid is drained from the water passage hole 27, air is supplied from the air supply hole 28, and air is discharged from the exhaust hole 14.
The water passage hole 27, the air supply hole 28, and the communication ports 26b and 26c are used as pipes for discharging the filtrate that has passed through the filter cloth 21 during the dehydration operation of the filter press 1.

FIG. 5 is a cross-sectional view of the filtration chamber during the dehydration operation of the filter press according to the present invention.
The dehydration operation of the filter press 1 is performed by closing the plurality of filter plates 19. By closing the plurality of filter plates 19, the filtration chamber 22 is formed between the filter plates 19 and 19. A pair of filter cloths 21 and 21 are stretched in the filtration chamber 22.
During the dehydration operation, by opening the communication ports 26b and 26c with a valve (not shown) and closing the communication ports 26a, sludge is supplied between the pair of filter cloths 21 and 21 from the stock solution supply hole 24, and the filter cloth 21 is permeated. The liquid is discharged from the water passage hole 27 and the air supply hole 28 through the communication ports 26b and 26c. When the water is discharged, solid content remains in the filtration chamber 22, and a dehydrated cake is produced.

FIG. 6 is a cross-sectional view of a filtration chamber supplying the impact body according to the present invention.
The communication ports 26a, 26b, and 26c are closed, and the cleaning liquid and the impact body 8 are supplied to the filtration chamber 22 through the stock solution supply hole 24.

FIG. 7 is a cross-sectional view of a filter chamber during cleaning of the filter cloth of the filter press according to the present invention.
In the filter press 1 of the present invention, after the dehydrated cake is discharged, the filter chamber 22 is filled with a cleaning liquid and an impact body 8 (balls, spheres, etc.) to clean the filter cloth 21. By supplying the cleaning liquid from the cleaning liquid storage tank 5 to the filtration chamber 22 through the cleaning liquid supply pipe 6 and injecting air from the air supply hole 28, the impact body 8 becomes the filter cloth 21 by the running water of the cleaning water and the stirring by the air. The dehydrated cake that collides and adheres to the filter cloth 21 is peeled off. The supplied washing water is discharged from the water passage hole 27, and the air is discharged from the exhaust hole 25.

Here, the impact body 8 will be described in detail. The impact body 8 has a shape and a size such as a spherical shape, a cylindrical shape, a box shape, and the like that can flow into the filtration chamber 22 from the impact body supply pipe 10 together with the cleaning liquid. Not limited.
By setting the specific gravity of the impact body 8 to 0.8 to 1.3, when it is supplied to the filtration chamber 22, it can float in the cleaning liquid and give an impact to the filter cloth 21.
The material of the impact body 8 can be freely selected from plastics such as polyamide, acrylic, polypropylene, polyethylene, polystyrene, polycarbonate and ABS, rubber such as NBR, EPM, EPDM, polyurethane and silicon, and other materials within the above specific gravity range. A gap may be provided in the impact body 8 to adjust the specific gravity.
A known pump can be used as the cleaning liquid pump 7 that conveys the impact body 8 together with the cleaning liquid, but a positive displacement rotary pump is preferable in consideration of damage to the pump.

In the filter press 1 of the present invention, the undiluted solution is dehydrated in the filtration chamber 22 in the filter plate 19 closed in parallel, the filter plate 19 is opened, and the dehydrated cake is discharged from the filtration chamber 22. The dehydrated cake is peeled off from the filter cloth 21 due to its own weight or vibration of the filter cloth 21. Since the dewatered cake that could not be completely peeled off due to its own weight or vibration or the clogged sludge adheres to the filter cloth 21, the filter cloth 21 is washed.

The cleaning of the filter cloth 21 includes a step S1 in which a plurality of filter plates 19 are first closed to form a filtration chamber 22 between the filter plates 19. The communication ports 26a, 26b, and 26c are provided with valves (not shown), all of which are closed. The on-off valve 11 of the impact body supply pipe 10 is also closed.
Since the dehydrated cake is discharged by opening the plate, an empty filtration chamber 22 is formed.

When the filtration chamber 22 is formed, the process proceeds to step S2 of supplying the cleaning liquid and the impact body 8 to the filtration chamber 22.
The on-off valve 11 is opened and the cleaning liquid pump 7 is started to supply the cleaning liquid and the impact body 8 to the filtration chamber 22. When the cleaning liquid and the impact body 8 are filled in the filtration chamber 22, the cleaning liquid pump 7 is stopped.

When the cleaning liquid and the impact body 8 are filled in the filtration chamber 22, the step S3 of stirring the filtration chamber 22 is started.
The cleaning liquid pump 7 is started with the on-off valve 11 closed and the valve of the communication port 26b open. The cleaning liquid supplied by the cleaning liquid pump 7 is supplied to the filtration chamber 22 through the stock solution supply hole 24. By supplying the cleaning liquid to the filtration chamber 22 and discharging the cleaning liquid from the water passage hole 27, a water flow of the cleaning liquid is generated in the filtration chamber 22. The cleaning liquid supplied to the filtration chamber 22 gives an impact to the filter cloth 21 by stirring the impact body 8 to peel off the dehydrated cake and the clogged sludge. The discharged cleaning liquid is returned to the cleaning liquid storage tank 5. After stirring by the cleaning liquid pump 7 for a predetermined time, the cleaning liquid pump 7 is stopped.

Next, in order to start the blower 15, the valves of the communication ports 26a and 26c are opened, and the valves of the communication ports 26b are closed. By activating the blower 15, the air sent from the blower 15 is supplied to the filtration chamber 22 from the air supply hole 28 to perform bubbling. In the filtration chamber 22, the filter cloth 21 is cleaned by air, and the air agitates the impact body 8 to further enhance the cleaning effect.
The air supplied to the filtration chamber 22 is discharged to the outside through the exhaust hole 25. After stirring with the blower 15 for a predetermined time, the blower 15 is stopped.

Next, the valve of the communication port 26b is opened, and the cleaning liquid pump 7 and the blower 15 are started at the same time to stir the filtration chamber 22.
By supplying cleaning water to the filtration chamber 22 by the cleaning liquid pump 7 and supplying air to the filtration chamber 22 by the blower 15, the impact body 8 largely idles in the filtration chamber 22. The filter cloth 21 is effectively washed by washing with a stream of water and bubbling.
After cleaning the filter cloth 21 for a predetermined time, the cleaning liquid pump 7 and the blower 15 are stopped to complete the cleaning.

The stirring by the cleaning liquid pump 7, the stirring by the blower 15, and the stirring by starting the cleaning liquid pump 7 and the blower 15 at the same time may be performed by selecting one of them according to the degree of clogging of the filter cloth 21. If selected, the order of execution may be changed as appropriate.

After the stirring of the filtration chamber 22 is completed, the process proceeds to step S4 in which the cleaning liquid and the impact body 8 are discharged from the filtration chamber 22.
The valves of the communication ports 26a, 26b and 26c are closed, the filter plate 19 is opened, and the sludge peeled off from the cleaning liquid, the impact body 8 and the filter cloth 21 remaining in the filtration chamber 22 is discharged.

Finally, step S5 is performed in which the discharged cleaning liquid and the impact body 8 are separated and the impact body 8 is recovered.
The discharged cleaning liquid, impact body 8, and sludge are collected in a collection tank 16 arranged below the filter press 1 and separated from each other.
If the impact body 8 has a specific gravity lighter than that of the cleaning liquid, the impact body 8 collects the impact body 8 floating in the recovery tank 16 and returns it to the impact body tank 9. If the specific gravity is heavier than the cleaning liquid, it is separated by a mesh or the like, and the impact body 8 is returned to the impact body tank 9.
The cleaning liquid and sludge are separated by sedimentation separation, the sludge settled in the recovery tank 16 is returned to the stock solution storage tank 2, and the supernatant liquid is returned to the cleaning liquid storage tank 5.

After discharging the cleaning liquid, the impact body 8 and the sludge from the filtration chamber 22, the filter plate 19 is closed to form the filtration chamber 22 again, and the sludge is supplied from the stock solution storage tank 2 to perform dehydration.

1 Filter press 8 Impact body 19 Filter plate 21 Filter cloth 22 Filter chamber

Claims (3)

In the filter cloth cleaning method of the filter press (1) for cleaning the filter cloth (21) arranged in the filtration chamber (22) formed between the plurality of filter plates (19).
A step (S1) of closing a plurality of filter plates (19) to form a filtration chamber (22) between the filter plates (19, 19), and
The step (S2) of supplying the cleaning liquid and the impact body (8) to the filtration chamber (22), and
The step (S3) of stirring the filtration chamber (22) and
The step (S4) of discharging the cleaning liquid and the impact body (8) from the filtration chamber (22), and
The step (S5) of separating the cleaning liquid and the impact body (8) and recovering the impact body (8),
A filter cloth cleaning method for a filter press, which comprises. The step (S3) of stirring the filtration chamber (22) is
The filter cloth cleaning method for a filter press according to claim 1, wherein the cleaning liquid is supplied to the filtration chamber (22) and the cleaning liquid is discharged from the filtration chamber (22). The step (S3) of stirring the filtration chamber (22) is
The filter cloth cleaning method for a filter press according to claim 1 or 2, wherein air is supplied to the filtration chamber (22) and air is discharged from the filtration chamber (22).

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