JPH0144085B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a solid-liquid separator, and more particularly to a solid-liquid separator called a filter cloth running type dehydrator or a filter cloth running type filtration machine.

PRIOR TECHNOLOGY In so-called filter cloth running type dehydrators and filters, solid and liquid are supplied to the surface of an endless filter cloth that can run and rotate in one direction to separate solid and liquid components. In order to perform liquid separation efficiently, a vacuum suction tank is provided on the back side of the filter cloth and opposite the solid-liquid supply section, and the liquid component in the solid-liquid supplied onto the filter cloth is sucked out and the liquid component is prevented from passing through. I'm trying to promote it. However, such a vacuum suction tank is maintained at a fairly high vacuum state, such as more than 500 mm in the water column, so
The filter cloth is sucked and bends greatly. Therefore, for example, in the device described in JP-A-50-83862, a large number of filter cloth guide rolls are arranged side by side at the vacuum suction port of the vacuum suction tank, which has a constant width in the running direction of the filter cloth. It guides the cloth and prevents it from bending. However, such conventional devices have drawbacks as explained below.

In other words, the filter cloth falls down greatly at the end of the filter cloth guide roll, but if the filter cloth guide rolls are arranged side by side at a vacuum suction port with a constant width, the ends of all filter cloth guide rolls will be in a line with the same part of the filter cloth. comes into contact with. Further, the side wall of the vacuum suction port also rubs the same portion of the filter cloth in a linear manner. Therefore, the filter cloth is subjected to a strong force due to suction, and the two areas mentioned above, namely the area where the end of the filter cloth guide roll comes into contact and the area where the side wall of the vacuum suction port rubs, are lined up. It wears out and starts to wear out. In severe cases, the filter cloth may tear. Therefore, in the conventional device described above, the life of the filter cloth is short.

On the other hand, the inventors of this invention previously filed a patent application in 1983.
- In the specification of No. 151615, a device is provided in which a vacuum suction port is widened toward the running direction of the filter cloth, and a plurality of filter cloth guide rolls are arranged at the vacuum suction port in accordance with the shape of the vacuum suction port that widens toward the bottom. Proposed. In this way, when the vacuum suction port is flared at the end and the filter cloth guide roll is arranged according to the shape of the vacuum suction port, the filter cloth guide roll as a whole comes into contact with the filter cloth with a width that corresponds to the extent of the width at the end. Therefore, like the conventional device mentioned above,
There is no linear contact at just one location. Further, it is also possible to prevent the side wall of the vacuum suction port from rubbing the filter cloth in a linear manner. In other words, the areas of contact or friction are dispersed. Therefore, damage to the filter cloth can be suppressed to some extent. However, even if this is done, the filter cloth still comes into contact with the end of the filter cloth guide roll and the side wall of the suction port at the depressed portion, and does not fundamentally solve the problem of damage to the filter cloth.

Problems to be Solved by the Invention The present invention solves the above-mentioned drawbacks of the conventional device, and
It is an object of the present invention to provide a solid-liquid separator that can prevent the filter cloth from being damaged by the edges of the filter cloth guide roll or the side walls of the suction port, and can dramatically extend the life of the filter cloth.

Means for Solving the Problems This invention for achieving the above object consists of an endless filter cloth provided so as to run in one direction on a fixed trajectory and freely rotate, and a solid liquid supply provided on the surface side of the filter cloth. and a reduced pressure suction tank provided on the back side of the filter cloth facing the solid liquid supply part, the reduced pressure suction tank is equipped with a reduced pressure suction port, and a plurality of filters are connected to the reduced pressure suction port. A cloth guide roll is arranged so that its center of rotation is in the width direction of the filter cloth, and the upper surfaces of the left and right side walls of the vacuum suction port and the upper surfaces of the right side walls facing each side wall are arranged so that the center of rotation is in the width direction of the filter cloth. The solid-liquid separator is characterized in that the ends of the filter cloth guide roll are covered with synthetic resin filter cloth guide sheets, and the inner edges of the left and right filter cloth guide sheets are flared toward the end. .

To explain one embodiment of the solid-liquid separator of the present invention, a so-called filter cloth traveling type transfer type dehydrator, in FIG. In this case, the endless filter cloth 1 is connected to the drive roll 2 and the guide roll 3,
It is set up so that it can run and rotate freely in the direction of the arrow on a certain track regulated by numbers 4, 5, etc. Above filter cloth 1
is stretched slightly upward with respect to the horizontal plane toward the guide rolls 3 to 4, and the upward angle is such that the liquid depth of the solid-liquid supply tank, which will be described later, is made as shallow as possible, and the supplied solid-liquid is The angle is preferably 5 to 20 degrees so that the contact area with the filter cloth can be increased and leakage of solid and liquid can be prevented.

The above-mentioned filter cloth is as described in Japanese Patent Application Laid-Open No. 59-115720. In other words, at least the weft yarns arranged in the width direction of the filter cloth have a single yarn diameter of 0.1~
Using a textile base material using 10 μm synthetic fiber thread,
The base material is mainly made of weft threads that are raised in the longitudinal direction (travelling and circumferential direction) to form a raised filter layer of ultrafine fibers with a thickness of 0.1 to 10 μm on the surface. Further, a knitted raised filter cloth as described in JP-A-58-207917 may also be used. In such a filter cloth, the naps lie uniformly in the longitudinal direction, but during use, as shown in FIG. Stretch it so that it faces.

A solid-liquid supply tank (solid-liquid supply section) 6 is installed on the surface side of the filter cloth 1 and between the guide rolls 3 and 4. However, in the present invention, the so-called solid-liquid supply part does not necessarily need to be configured as a tank, and may be a pipe or a gutter that can directly discharge the solid-liquid.

The back side of the filter cloth 1 is connected to an intake means (not shown) via an intake pipe 7 at a position facing the solid-liquid supply section 6, and the back side is reduced in pressure to a water column of 500 m or more. Decompression suction tank 8 that can maintain
is installed. This reduced pressure suction tank 8 is equipped with a liquid component discharge pipe 9. In addition, a plurality of filter cloth guide rolls 11 are arranged in the vacuum suction port 10 facing the back surface of the filter cloth 1 in the running and circumferential direction of the filter cloth 1 . The filter cloth guide roll 11 may be a roll with a smooth surface, but it may also be a so-called perforated roll in which a large number of holes are bored in a cylindrical roll, or a cylindrical roll or a solid roll with grooves in the circumferential direction on the surface. It is preferable to use so-called grooved rolls having spiral grooves cut therein, since the actual opening area of the vacuum suction ports 10 does not decrease significantly even if they are arranged closely, and a large degree of vacuum can be obtained with a small amount of power.

Referring to FIG. 2, the vacuum suction port 10 widens toward the end in the direction of travel and circulation of the filter cloth (in the direction of the arrow). And the vacuum suction port 10
An erection frame 12, which similarly widens at the end, is removably attached. Therefore, in this embodiment, the construction frame 12 effectively forms the vacuum suction port 10.

The filter cloth guide roll 11, as shown in FIG.
The filter cloth is divided into three groups and supported by the construction frame 12 in the width direction of the filter cloth. Further, the filter cloth guide rolls 11 divided into three groups are each three in a row in the width direction of the filter cloth and are supported by a common shaft 13 at intervals, The two outermost pieces in the row are both oriented slightly outward in the filter cloth running direction, forming a V-shape in the filter cloth running and circumferential direction. In addition, the construction frame 12
The upper surface of the left frame 20 located on the left side and the upper surface 21 of the right frame 21 located on the right side with respect to the traveling and circumferential direction of the filter cloth, and the filter cloth guide roll 11 facing the left frame 20 and the right frame 21, respectively. The ends are covered with filter cloth guide sheets 14 and 15. These filter cloth guide sheets 14 and 15 are made of a synthetic resin such as fluororesin, polyamide resin, polyester resin, vinyl chloride resin, etc., with a thickness of about 0.3 to 2 mm, which does not easily damage the filter cloth or filter cloth guide roll 11 and is resistant to wear. It is made up of The distance between the inner edges 16 and 17 of the filter cloth guide sheets 14 and 15 gradually decreases toward the traveling and circumferential direction of the filter cloth, and increases toward the downstream side.

Referring to FIGS. 2 and 3, the three filter cloth guide rolls 11 arranged in a row in the width direction of the filter cloth have sliding bearings 18 fitted to both ends of each filter cloth guide roll 11, It is supported by the shaft 13 via 19. Both ends of the shaft 13 are connected to U-shaped open holes 22 (2) provided in the left and right frames 20, 21.
3), and the portion between each filter cloth guide roll 11 is provided on the construction frame 12 with left and right auxiliary frames 24,
It fits into U-shaped open grooves 26 and 27 provided in 25. Therefore, the filter cloth guide sheets 14, 15
By lifting the filter cloth guide roll 11, it can be removed together with the shaft 13 from the construction frame 12. In addition, the filter cloth guide sheets 14, 15
is attached to the tank wall of the vacuum suction tank 8.

Referring again to FIG. 1, the guide roll 4
A transfer drum 28 and a press roll 29 are disposed facing each other between the drive roll 2 and the drive roll 2 with the filter cloth 1 in between. Further, a wedge-shaped scraper 30 made of a relatively soft material such as rubber or synthetic resin is brought into contact with the surface of the transfer drum 28 . Furthermore, a shooter 31 for discharging cake is installed directly below the scraper 30 and at a position higher than the drive roll 2. This shooter 31 is made of a plate made of metal or synthetic resin,
It is inclined at an angle of 30 to 60 degrees with respect to the horizontal plane, and is installed at a position approximately 0.5 to 20 mm away from the surface of the transfer drum 28.

A draining roll 32 is installed between the guide rolls 5 and 3 so as to contact the surface of the filter cloth 1 and push the filter cloth 1 upward.

A filter cloth cleaning nozzle 33 is provided on the surface side of the filter cloth 1 and between the guide roll 5 and the draining roll 32.
is installed. This filter cloth cleaning nozzle 33 is
It is like a plurality of nozzles installed in a row in the longitudinal direction of a corrosion-resistant pipe such as a stainless steel pipe, an aluminum pipe, or a vinyl chloride pipe, and the nozzles are installed so that the longitudinal direction is in the width direction of the filter cloth 1. ing. Further, on the back side of the filter cloth 1, a filter cloth pressing plate 34 is installed at a position facing the filter cloth cleaning nozzle 33. The filter cloth holding plate 34 is made of a corrosion-resistant and rigid material such as stainless steel, vinyl chloride, and aluminum, and is processed into a flat plate or perforated plate as a whole. The filter cloth 1 is bent slightly upward as shown in FIG. 1 so that it will not be damaged even if the filter cloth 1 comes into contact with it. Note that the filter cloth pressing plate 34 is
It is installed at a position of about 0.5 to 50 mm from the back surface of the filter cloth 1. However, such a filter cloth pressing plate is not necessarily necessary.

Between the draining roll 32 and the guide roll 3 and on the back side of the filter cloth 1, the filter cloth cleaning nozzle 33 is installed.
Another filter cloth cleaning nozzle 35 similar to the above is installed.

Between the guide roll 3 and the solid liquid supply tank 6,
A brush-like comb 36 is fixedly installed so that its bristles come into contact with the surface of the filter cloth 1. The comb 36 is, for example, a rod-shaped base made of plastic or the like and synthetic fibers such as polyester fibers or polyamide fibers are flocked thereto.

In the above embodiment, a construction frame having the same shape as the vacuum suction port is attached, and the filter cloth guide roll is supported on the construction frame. The filter cloth guide roll may be supported using the filter cloth guide roll.

Further, the shape of the vacuum suction port may be either widened towards the running direction of the filter cloth as shown in the embodiment, or rectangular.

Furthermore, it is not necessarily necessary to divide the filter cloth guide rolls into three groups. The so-called three-group arrangement as shown in the embodiment is advantageous when the width of the filter cloth is wide, but the middle filter cloth guide roll group may not be provided, and only two groups on the left and right may be provided. Further, in the case of a two-group arrangement, as described in the above-mentioned Japanese Patent Application Laid-Open No. 50-83862, a configuration may be adopted in which the filter cloth guide rolls are arranged in a V-shape in a rectangular construction frame. Furthermore, only one group of filter cloth guide rolls may be arranged so that the center of rotation thereof is in the width direction of the filter cloth and in the running and circumferential direction of the filter cloth.

Furthermore, the so-called V-shaped arrangement of the filter cloth guide rolls is not necessarily required. however,
A V-shaped arrangement is preferred because it allows the filter cloth to be spread out in the width direction.

In the above, a so-called filter cloth traveling type transfer type dehydrator has been described, but the solid-liquid separator of the present invention is a so-called filter cloth traveling twin type that compresses a solid liquid sandwiched between two filter cloths with a squeeze roll. It may be a cloth-type dehydrator, or it may be a so-called filter cloth running type filtration machine that does not have a squeezing mechanism or a transfer mechanism.

Function To explain the function of the above-mentioned dewatering machine, it is driven by the drive roll 2, travels in the direction of the arrow, and a solid liquid containing a solid component and a liquid component is delivered from the solid liquid supply tank 6 onto the filter cloth 1 that is circulating. supply. The liquid component in the supplied solid liquid passes through the filter cloth 1 by gravity and by the reduced pressure suction effect provided by the reduced pressure suction tank 8 and is collected in the reduced pressure suction tank 8 . At this time, the filter cloth 1 is subjected to a large force due to suction, but it runs stably due to the action of the filter cloth guide roll 11 and the filter cloth guide sheets 14 and 15.

The liquid components collected in the vacuum suction tank 8 are discharged to the outside of the dehydrator via a discharge pipe 9. On the other hand, filter cloth 1
The components that have not passed are carried between the transfer drum 28 and the squeeze roll 29 as the filter cloth 1 travels and rotates, and are squeezed to squeeze out the liquid components, forming a so-called cake. The cake is then transferred from the filter cloth 1 to the surface of the transfer drum 28, scraped off by the scraper 30, and discharged to the outside of the dehydrator. Since the scraped cake is guided by the shooter 31, it will not fall or adhere to the filter cloth 1.

The filter cloth 1 then reaches the position of the filter cloth cleaning nozzle 33, and is washed from its surface side by the cleaning water jetted from the filter cloth cleaning nozzle 33. At this time, the filter cloth pressing plate 34 prevents the filter cloth 1 from bending, twisting, or vibrating due to the pressure of the washing water, and ensures stable running of the filter cloth 1. Further, it acts to restrict the travel path of the filter cloth 1 so that the distance between the filter cloth 1 and the filter cloth cleaning nozzle 33 does not change significantly and the cleaning effect does not deteriorate.

The filter cloth 1 is then cleaned from the back side by a filter cloth cleaning nozzle 35 after liquid components from washing are removed by a drain roll 32, and so-called clogging substances taken inside are removed. Then, after the direction of the nap is aligned by the combing device 36, it reaches the solid-liquid supply tank 6 again and is subjected to the next dehydration.

The device of this invention can be used in a variety of applications. For example, it can be used to separate solid components from lake or river water. In addition, sludge, scum, etc. generated by sewage treatment, such as so-called suspended sludge, such as surplus sludge produced as a by-product from activated sludge treatment equipment, and so-called fixed sludge, discharged from biofilm treatment equipment, Frodsk,
It can be used for filtering, concentrating, and dehydrating wash water, sludge, etc. in particular,
For example, sludge generated from water and sewage treatment, surplus sludge generated from septic tanks, sludge generated from human waste treatment plants, scum generated from pressurized flotation operations, flocs generated from industrial wastewater treatment, flocs of flocs, and sand. It can be used for solid-liquid separation such as backwash water of various filters such as filters. Also,
For example, paper pulp manufacturing, food manufacturing, alcoholic beverage manufacturing,
It can be used for solid-liquid separation in various manufacturing industries, such as the brewing industry for miso, and for recovering valuable materials in chemical processes.

Effects of the Invention In the solid-liquid separator of the present invention, the vacuum suction tank is equipped with a vacuum suction port, and a plurality of filter cloth guide rolls are arranged in the vacuum suction port so that the center of rotation is in the width direction of the filter cloth. At the same time, the filter cloth running at the vacuum suction port,
Since the upper surfaces of the left and right side walls in the circumferential direction and the ends of the filter cloth guide rolls facing these side walls are covered with synthetic resin filter cloth guide sheets, the fall of the filter cloth at the ends of the filter cloth guide rolls is prevented. In addition to preventing wear and damage to the filter cloth caused by the edges, the inner edges of the left and right filter cloth guide sheets are flared toward the end, so the filter cloth The filter cloth guide sheet is made of a synthetic resin that does not easily damage the filter cloth, and the guide sheet contacts the filter cloth not in a linear manner but with a width corresponding to the degree of spread at the end, so that the contact portions are dispersed. At the same time, wear and damage to the filter cloth can be prevented, and the life of the filter cloth can be greatly extended.

[Brief explanation of drawings]

Fig. 1 is a schematic partial cross-sectional side view showing an embodiment of the solid-liquid separation device of the present invention for a filter cloth traveling transfer type dehydrator, Fig. 2 is a schematic plan view of a vacuum suction tank, and Fig. 3 is a schematic plan view of a vacuum suction tank. FIG. 2 is a schematic vertical cross-sectional view showing the main parts of the reduced pressure suction tank. 1: Filter cloth, 2: Drive roll, 3, 4, 5: Guide roll, 6: Solid-liquid supply tank (solid-liquid supply section), 7:
Intake pipe, 8: Decompression suction tank, 9: Discharge pipe, 10: Decompression suction port, 11: Filter cloth guide roll, 12: Erection frame, 13: Shaft, 14: Left side filter cloth guide sheet, 1
5: Right side filter cloth guide sheet, 16: Inner edge of left side filter cloth guide sheet, 17: Inner edge of right side filter cloth guide sheet,
18, 19: Thrust bearing, 20: Left side frame, 2
1: Right side frame, 22, 23, 26, 27: Open groove,
24: Left auxiliary frame, 25: Right auxiliary frame, 28: Transfer drum, 29: Squeezing roll, 30: Scraper,
31: Shooter, 32: Drainer roll, 33,
35: Filter cloth cleaning nozzle, 34: Filter cloth press plate, 3
6: Combing machine.

Claims (1)

[Claims] 1. An endless filter cloth that runs in one direction on a constant trajectory and is freely rotatable, a solid-liquid supply section provided on the front side of this filter cloth, and a back side of the filter cloth opposite to this solid-liquid supply section. and a reduced pressure suction tank provided in the vacuum suction tank, the reduced pressure suction tank is provided with a reduced pressure suction port, and a plurality of filter cloth guide rolls are arranged at the reduced pressure suction port so that the center of rotation is in the width direction of the filter cloth. The upper surfaces of the left and right side walls of the reduced pressure suction port with respect to the traveling and circulating direction of the filter cloth, and the ends of the filter cloth guide roll facing each of the side walls are covered with a synthetic resin filter cloth guide sheet. A solid-liquid separator characterized in that the inner edges of the left and right filter cloth guide sheets have a shape that widens toward the end.