JPS625642B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for discharging cake on a filter plate in a filter having a horizontal filter plate.

Horizontal disk-type filters are suitable for filtering stock solutions containing a large amount of solids, but there is a problem in discharging a large amount of cake that accumulates on the filter disk.

Conventionally, there is a device in which a filter plate is rotated at high speed by an electric motor to shake off the cake on the filter plate by centrifugal force when discharging the cake. However, with this conventional device, if the cake has strong adhesion and low specific gravity, it is difficult to discharge the cake, and in general, it is difficult to discharge the cake from the center of the filter where the centrifugal force is small. It is. Additionally, a large electric motor is required to rotate the filter plate at high speed.

Also, JP-A No. 57-94316 and Utility Model Application No. 57-94316
As disclosed in Publication No. 181320, a cake discharge path and a collecting groove are provided at the outer circumference of the filter disk, and four scraping plates curved in an arch shape are protruded in a cross shape above the filter disk. An electric motor is connected to the impeller, and as the impeller rotates, the cake accumulated on the filter disk is scraped off to the outer circumference of the filter disk using a scraping plate, and a cake discharge path is created. There is a device that allows it to be discharged into the sump groove. However, in this conventional device, the cake discharge path and retention groove are provided at the outer circumference of the filter plate.
Becomes large. Moreover, each scraping plate of the impeller is only curved in an arc shape, so the cake scraping movement distance per unit rotation angle of the impeller is long, and therefore the power to rotate the impeller is is large,
Requires a large electric motor.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the conventional devices as described above, and to provide a cake discharging device for a filter plate that is easy to discharge the cake and is compact.

The present invention provides a filter in which filter plates are installed horizontally, in which a plurality of annular filter plates are arranged concentrically in multiple stages to form a cake falling path that passes through the center of each filter plate, A spirally curved scraping plate is placed on top of each filter plate, and each filter plate and each scraping plate are relatively rotatable. This cake discharging device is characterized in that the cake deposited on the cake is scraped off to the inner circumferential side of each filter plate by each scraping plate so that the cake can fall into a cake falling path.

The cake discharging device of the present invention scrapes the cake on the filter plate with the scraping plate and drops it from the filter plate by relative rotation of the filter plate and the scraping plate on the filter plate, so the cake has a strong adhesive force and has a low specific gravity. Even if it is a small cake or a cake accumulated on the inner peripheral side of the filter plate, it is easy to discharge. Moreover, the power required to rotate the filter disk and the scraping plate relative to each other is smaller than the power required to rotate the filter disk at high speed to shake off the cake.

Moreover, since the cake discharging device of the present invention has the cake falling path provided in the center of the circular disk-shaped filter plate,
It is more compact than the conventional device in which the cake discharge path and trap groove are provided at the outer circumference of the filter disk. in addition,
Since the scraping plate is spirally curved, compared to the conventional device in which the scraping plate that protrudes in a criss-cross shape of the impeller is curved in an arch shape, the scraping plate is curved in a spiral manner. The scraping movement distance of is short, therefore,
The power required to relatively rotate the scraping plate can be small.

Next, examples of the present invention will be described.

The horizontal filter plate type filter equipped with the cake discharging device of this example shown in Figs. The lower filter disk 2 is suspended by a plurality of hanging bolts 7 from the mounting flange 6 which is sandwiched between the container body 1 and the lid 5 placed over the upper end opening. The middle filter plate 3 and the upper filter plate 4 are sandwiched between the lower filter plate 2, and a passage cylinder 9 is connected to the bottom plate of the vessel body 1 by a connecting cylinder 8 vertically installed on the inner periphery of the lower filter plate 2. The undiluted liquid passage 10 is connected to the circumferential surface of the passage tube 9, and the inside of the filter disks 2, 3, 4 stacked in three stages and the inside of the lid 5 communicating therewith are formed into an undiluted liquid passage. On the upper surface of the annular filtrate chamber 11 formed in each stage of the filter plates 2, 3, and 4, a circular plate-shaped filter plate 12 is provided with a large number of small holes.
and a filter cloth 13 or filter paper, and connect the filtrate chamber 11 of each stage to the stock solution passage through the filter plate 12 covered with the filter cloth 13, and also connect the filtrate chamber 11 of each stage to the Through holes 14 penetrating the peripheral walls of the filter disks 2, 3, 4 communicate with the outer circumferential sides of the filter disks, and a filtrate passage is established between the three-stage laminated filter disks 2, 3, 4 and the vessel body 1. A filtrate passage 15 is connected to the peripheral wall of the container body 1. Further, an overflow path 16 for the stock solution is connected to the lid body 5, a backwash path 17 is branched and connected to the filtrate path 15, and a filter cloth 18 for residual liquid is placed over the lower end opening of the passage cylinder 9. Filter plate 1
9 is attached via a saucer 20, a filtrate passage 21 for the residual liquid is connected to the saucer 20, and an air passage 22 for pushing out the residual liquid is branched and connected to the overflow passage 16 for the stock solution.

Furthermore, a bearing cylinder 23 provided at the center of the upper end of the lid body 5
A rotary shaft 25 is inserted into the bearing tube 24 provided at the center of the connecting tube 8 of the lower filter disk, and a rotating shaft 25 is inserted through the center of the filter disk 2, 3, 4 of each step. The cross-shaped mounting arms 26 are mounted in three stages via keys 27 so as to be slidable only in the axial direction, and the mounting arms 2 at each stage are
Scraping plate 28 with a spirally curved elongated plate on the lower surface of 6
, and place the scraping plates 28 of each stage on top of the filter plates 2, 3, and 4 of each stage, and the position between the mounting arms 26 of each stage, the upper position of the mounting arm 26 of the upper stage, and the position of the lower stage. Snap springs 29 are fitted into the rotating shafts 25 at the lower positions of the mounting arms 26, and the mounting arms 26 of each stage are fitted.
A spiral spring 30 is fitted between the snap spring 29 and the snap spring 29 located above the mounting arm 26 of each stage.
is pressed toward the snap spring 29 at the lower position of each stage, the scraping plate 28 of each stage is brought into contact with the filter cloth 13 of the filter disc of each stage, and the bearing tube 23 of the lid body 5 is pressed.
The rotary cylinder 32 is rotatably attached to the bearing ring 31 provided at the upper position, and the bearing cylinder 2 of the lid body is installed inside the rotary cylinder 32.
The upper end of the rotary shaft 25 protruding from the rotary shaft 25 is fitted via a key 33 so that it can slide only in the axial direction, and a huddle 34 is attached to the rotary tube 32. The shaft 25 and the mounting arms 26 and scraping plates 28 of each stage are arranged to rotate, and are rotatably attached to the upper end plate of the rotating cylinder 32 through the screw shaft 35, and suspended inside the rotating cylinder 32. Spiral shaft 3
5 is screwed into the screw hole 36 drilled in the upper end surface of the rotating shaft 25, a handle 37 is attached to the upper end of the screw shaft 35, and the screw shaft 35 is rotated by the rotation of the handle 37. 25, and accordingly, the mounting arms 26 and scraping plates 28 of each stage are raised and lowered.

When using the filter of this example, a stock solution containing a large amount of solids is supplied to the stock solution path 10. Then,
The stock solution flows from the stock solution path 10 into the filter disks 2, 3, 4 and the lid body 5.
The filtrate from which the solid content has been removed flows into the filtrate chamber 11 of each stage through the filter cloth 13 and filter plate 12 of each stage's filter plate, and flows into the filtrate chamber 11 of each stage. The solid content is deposited as a cake on the filter cloth 13,
The filtrate in the filtrate chamber 11 of each stage flows through each through hole 14 into the filtrate passage between the filter disks 2, 3, 4 and the vessel body 1, and is taken out of the vessel body 1 through the filtrate passage 15. Ru.

When a large amount of cake is deposited on the filter disk, first, high pressure air is supplied to the air passage 22 in order to drain out the raw solution, that is, the residual liquid remaining in the filter.
Then, the high-pressure air flows from the air passage 22 into the liquid passages in the lid body 5 and the filter plates 2, 3, and 4, presses the remaining liquid in the liquid passage into the lower passage cylinder 9, and presses the remaining liquid in the liquid passage into the passage cylinder 9. The residual liquid passes through the residual liquid filter cloth 18 and the filter plate 19,
As the filtrate flows into the tray 20, a cake is deposited on the filter cloth 18, and the filtrate in the tray 20 is taken out via the residual filtrate path 21. After draining the residual liquid, in order to discharge the cake, remove the saucer 20 and remove the filter cloth 18 and filter plate 19 for the residual liquid.
A bucket (not shown) is placed below the open lower end opening of the passage cylinder 9, and the handle 34 for rotating the scraping plate is
The spiral scraping plate 28 of each stage is rotated clockwise in FIG. 2 by rotating. Then, the cake accumulated on the filter cloth 13 of each stage is scraped off by the spiral scraping plate 28 of each stage that rotates while sliding on the filter cloth 13 of the filter disc of each stage. and moves at a slow speed over the filter disks 2, 3, and 4 of each stage toward the inner circumference,
The cake falls from the inner periphery of the filter discs 2, 3, and 4 of each stage, passes through the center of the filter disc of each stage, reaches the passage tube 9, falls through the passage tube 9, and falls into the bucket. Fall. After discharging the cake, in order to backwash the filter cloth 13, the scraping plate lifting handle 37 is rotated to lower the rotating shaft 25, and each stage of the scraping plate 28 is moved to the respective stage of the filter. After strongly contacting the filter cloth 13 of the disk to prevent the filter cloth 13 from floating due to backwashing, water is supplied to the backwash path 17. Then, the backwash water flows from the backwash path 17 into the filtration chamber 11 of each stage through the filtrate passage between the vessel body 1 and the filter plates 2, 3, and 4 and the through holes 14, and the filtrate of each stage flows into the filtration chamber 11 of each stage. After passing through the filter plate 12 and filter cloth 13 in the chamber and washing the filter cloth 13, the filter plate 2 of each stage,
The backwashing water falls from the inner circumferential edge of Nos. 3 and 4 into a fall path that passes through the center of the filter disks of each stage and reaches the passage cylinder 9, and then passes through the passage cylinder 9 and is discharged.

In the filter of the above illustrated embodiment, the filter plate is fixed and the scraping plate is rotated, but conversely, the scraping plate may be fixed and the filter plate is rotated. Further, the filter disk and the scraping plate may be rotated in opposite directions, and in short, the filter disk and the scraping plate may be rotated relative to each other.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional front view of a horizontal filter plate type filter equipped with a cake discharge device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional plan view of the same filter. 2, 3, 4: Filter disk, 28: Scraping plate.

Claims (1)

[Claims] 1 In a filter with horizontally installed filter disks, a plurality of disk-shaped filter disks are arranged concentrically in multiple stages to form a cake fall path that passes through the center of each filter disk, and each filter disk is A spirally curved scraping plate is placed on top of each filter plate, and each filter plate and each scraping plate are relatively rotatable, and the relative rotation causes the deposition on each filter plate. A cake discharging device characterized in that the cake is scraped onto the inner circumferential side of each filter plate using each scraping plate, and is allowed to fall into a cake falling path.