JPH02102706A - Dehydrator - Google Patents

Abstract

PURPOSE:To dehydrate mud with high efficiency by agitating the mud in a tank, dehydrating the mud by the compressed air injected from the inside of a screw shaft during transfer of the mud, and discharging the filtrate from a filter cloth to the outside of the tank. CONSTITUTION:The filter cloth 10 is fixed over the inner surface of the almost lower half side plate of a tank with a clearance in between in the longitudinal direction of the mud dehydrating tank 2. A hopper 1 for supplying mud into the tank 2, a mud intake valve 15 which is opened to supply the mud from the hopper 1 to the mud supply opening of the tank 2 when the mud is supplied, and a mud discharge valve 16a which is opened to discharge the dehydrated mud to the outside of the tank from a discharge opening when the dehydrated mud is discharged are provided. Compressed air is injected into the tank 2 from many nozzles 12b through the inside of the shaft 12 when mud is dehydrated, the screw shaft 12 for agitating and transferring the mud in the tank is horizontally provided, and the water removed from the mud by the compressed air from the shaft 12 is discharged through the filter cloth 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dewatering device for dewatering dredged mud in, for example, ports, rivers, lakes, and the like.

[Conventional technology] In recent years, during dredging work for rivers, lakes, etc., when dredged mud is dumped on land or reclaimed land, the dredged mud contains water, so if it is directly dumped, it will dry out in the sun. If it takes a considerable number of days, or if a vehicle such as a dump truck is used to get to the dumping site, a considerable amount of water that is not originally needed will be transported, which will not only be wasted, but also waste water during the transportation. This can cause secondary pollution such as mud splashing out.

Therefore, before dumping or transporting dredged mud,
In recent years, dehydration using a dehydrator has been practiced.

[Problem to be solved by the invention] Conventional dewatering equipment of this type employs a mud compression method, a vacuum adsorption method, and a specific gravity separation method, but these methods require the addition of polymer flocculants, etc. Not only does running cost become high because of the need for additives, but depending on the type of additive, it may become industrial waste with limited locations for disposal.

Additionally, methods that compress mud, use vacuum, or utilize differences in specific gravity have limitations in their dewatering performance.
The drawback was that highly efficient dehydration was difficult.

The purpose of the present invention is to
The present invention provides a dewatering device that can highly efficiently dewater water in mud.

[Means for Solving the Problems] An example of the means for achieving the object of the present invention has an opening for supplying mud and a discharge opening for discharging dewatered mud, and has an opening approximately at the lower end in the longitudinal direction. at least one mud dewatering tank having a filter cloth fixed to the inner surface of the tank side plate with a gap therebetween, a hopper for supplying mud to the mud dewatering tank, and a valve that opens when mud is supplied to drain the mud from the hopper. A mud intake valve that enables mud to be supplied to the mud supply opening of the tank, and a mud discharge valve that opens when dewatering mud is discharged to enable the mud to be discharged from the discharge opening to the outside of the tank, Inside the mud dewatering tank, compressed air passes through the shaft and blows out from a number of nozzles during the dewatering process, and a screw shaft is installed in the horizontal direction to agitate and transfer the stored mud while rotating, and the pressurized air jets out from the screw shaft. This dewatering device is characterized in that the water released from the mud is drained out of the tank through the filter cloth.

[Function] The dewatering device configured as described above performs pressure dewatering using pressurized air ejected from the inside of the screw shaft while agitating and transferring the mud housed in the tank, and drains the filtrate from the filter cloth outside the tank. The dewatered mud is transferred by a screw shaft and discharged from the tank through the mud discharge opening.

[Example] The present invention will be described in detail below based on an example shown in the drawings.

Embodiment 1 FIG. 1 is a partially cutaway side view of Embodiment 1 of the dewatering device according to the present invention, FIG. 2 is a sectional view taken along the line A-A, FIG. Figure 4 is a diagram showing the distribution of water in mud.

Reference numeral 1 denotes a hopper with an open top, and a screen (not shown) formed in a lattice pattern is attached to the top opening surface of the hopper, which is filled with mud excavated by a civil engineering machine such as a backhoe (hereinafter, undehydrated mud is referred to as the source). is injected through the screen. The screen is used to remove bulky debris from the source water that is fed into the hopper 1, and the screen is moved through a vibrator (not shown) to remove large chunks of the source material that are caught in the grid. Crush it into a size suitable for dehydration and drop it. Reference numeral 2 is a horizontally elongated cylindrical tank with both ends closed.A porous casing (to be described later) for passing moisture is attached to the lower tank part 4, which has an approximately semicircular cross-section, and is attached to the outer periphery of this lower tank part 4°. The filtrate is stored in the filtrate receiving tank 3. The filtrate receiving tank 3 is connected to the upper tank portion 4 via the joint member 5.
By driving the filtrate tank opening/closing cylinder 21, the filtrate receiving tank 3 is opened and closed relative to the upper tank portion 4 as shown in FIG. 2, and is locked in the closed position by the joint bin 6. It has become.

The other end of the upper tank section 4 extends to an extension of the filtrate receiving tank 3, and a mud discharge pipe 16 for discharging dehydrated mud is attached to the lower part of the other end, and the mud is discharged by an air or hydraulic cylinder 16b. Mud is discharged from the mud discharge pipe 16 by opening the valve 16.

Further, the upper tank part 4 has a level sensor 22 at the top that detects the level of mud contained in the tank 2, and an atmosphere release valve 17a that opens and closes under drive control of an air or hydraulic cylinder 17b.
An atmosphere opening pipe 17 is provided.

The lower tank portion 4° is provided with a porous casing 9 on the inner peripheral surface, a filter cloth 10 is attached to the outer peripheral surface of the porous casing 9, and the filter cloth 10 is connected to the porous casing 9 through a porous filter cloth cover 11. It is removably fixed to.

The filtrate receiving tank 3 also has a filtrate discharge pipe 1 at the bottom of one end.
8 is attached, and the filtrate accumulated inside the filtrate receiving tank 3 is discharged to the outside of the tank through the filtrate discharge pipe 18, and the filtrate discharge valve 18a is opened and closed by driving the air or hydraulic cylinder 18b. The filtrate discharge pipe 18 is opened and closed. A filter cloth cleaning pipe 19 is attached to one end wall of the filtrate receiving tank 3 between the inner peripheral surface and the porous filter cloth cover 11, and a filter cloth cleaning valve 19a is controlled to open and close by an air or hydraulic cylinder L9b. By opening it, cleaning air is supplied into the tank 2 through the filter cloth cleaning pipe 19,
The filter cloth 10 is washed.

Further, the lower part of the hopper 1 is attached to the upper part of one longitudinal end of the tank 2 via a mud intake valve 15, and by opening this mud intake valve 15 via air or a hydraulic cylinder 15a, the inside of the hopper 1 can be opened. The source of the water is supplied by falling water.

Inside this tank 2, a hollow screw shaft 12, which also serves to supply compressed air for stirring, transporting and dehydrating the source water, is provided rotatably along the length direction, and one penetrating end is connected to a rotary seal 13. A screw shaft chain wheel 8 connected to the screw shaft drive motor 7 via a chain 8a is fixed to the other penetrating end, and is rotated by the driving force of the motor 7. Note that the shaft may be rotated by a hydraulic motor or the like.

This screw shaft 12 has a rotary seal 13 in the hollow part.
(the other end is closed), and a large number of air nozzles 1 are provided in the peripheral wall L2a and communicated with the hollow part.
2b is formed, and when the pressurizing valve 20 is opened, compressed air from a compressed air source (not shown) flows into the rotary seal 13,
The air is ejected from the air nozzle 12b into the tank 2 through the hollow part. Further, screw blades 14 are formed in a spiral shape on the outer periphery of the screw shaft 12.
According to the rotation of the tank 2, the mud in the tank 2 is transferred from one end to the other end while being stirred.

The structure of the first embodiment has been described above, and its operation will be explained below.

When feeding into the source tank 2 in the hopper 1, the intake valve 15, the atmosphere release valve 17a, and the filtrate discharge valve 18a are kept open, and the other valves are kept closed. The screw shaft 12 is always driven to rotate, and is appropriately rotated clockwise and counterclockwise during the dewatering process to prevent mud from accumulating in a part of the tank 2, and when the dewatering process is finished, the mud is discharged. It rotates to transfer mud toward the pipe 16.

When the level sensor 22 detects that the tank 2 is full of mud, the intake valve 15 and the atmosphere release valve 17
a is closed to bring the inside of the tank 2 into a sealed state, and the pressurizing valve 20 is opened to supply compressed air into the tank 2 from the air nozzle 12a of the rotating screw shaft 12. here,
As shown in Figure 4, the source water housed in the tank 2 contains surface-adhered water around solid mud, cracked megalithic capillary-bound water in cracks, wedge-shaped capillary-bound water, pore water, and free water. There is also internal water inside. And screw shaft 1
When compressed air is pressurized into the tank 2 from the air nozzle 12a of No. 2, as shown in FIG. As the water passes through the filter cloth 10, water at the source passes through the filter cloth 10, becomes a dew-like filtrate, and accumulates in the filtrate receiving tank 3. At that time, as shown in Figure 3, the compressed air penetrates the solid container and even the internal water in the solid container is removed, and the source is uniformly stirred by the screw shaft. It will be dehydrated.

The time for supplying compressed air into the tank 2, that is, the dewatering time, is set by a timer (not shown) according to the target water content based on the amount of source water to be accommodated, the water content of the source water, the compressed air pressure, etc. When the time is reached, the pressurizing valve 20 is closed to stop the supply of pressurized air into the tank 2, and the atmosphere release valve 17a is opened to release the inside of the tank 2 to the atmosphere. The opening time of the atmosphere release valve 17a is controlled by an atmosphere release valve open timer, and when the time of the atmosphere release valve open timer expires, the discharge valve lea is opened, and the dehydrated treated mud in the tank 2 is discharged to the outside of the tank. .

At the same time as the discharge valve 16a is opened, the filtrate discharge valve 18a is closed, the filter cloth cleaning valve 19a is opened, and the porous casing 9, filter cloth 10. The porous filter cloth cover 11 is cleaned with air. Discharge valve l
The valve opening time of ea is controlled by a discharge valve timer, and when the discharge valve timer times up, the discharge valve 16a, filter cloth cleaning valve 19a, and atmosphere release valve 17a are closed, and the intake valve 15 and filtrate discharge valve 18a are opened. The source water is taken into tank 2 again.

In addition, in this first embodiment, one tank 2 is attached to one hopper 1, but if two or more tanks 2 are attached, for example, to perform dehydration processing continuously,
- Improved membrane water treatment ability.

Example 2 FIG. 5 is a schematic sectional view of the second embodiment.

In this embodiment, two lower openings are formed in the hopper 1, and the hopper 1 is connected to two vertically arranged tanks 33 and 34 having the same structure through intake valves 31 and 32 provided in each opening.

The tanks 33 and 34 have a filter cloth 36 attached to the outer peripheral surface of a cylindrical porous casing 35 in a tank side plate (not shown) with an open bottom, and a porous filter cloth cover 37 that connects the filter cloth 36 from the outside. It has a structure that is removably fixed to a porous casing 35, and a discharge valve 38, 39 for discharging dehydrated mud is attached to the lower end, and a large number of air nozzles 4. , O are formed in the pressure air pipes 41, 42 in the vertical direction, and by opening the respective pressure valves 43, 44, compressed air from a compressed air source (not shown) is supplied into the tank. ing.

On the other hand, in the tanks 33 and 34, the lower end of the tank side plate is located above the lower end of the porous casing 35, and a filtrate tray 45 for receiving filtrate is provided at the lower end, and the filtrate in the filtrate tray 45 is passed through a filtrate pipe (not shown). It is discharged.

43° and 44° are atmospheric release valves provided in tanks 33 and 34, respectively.

Note that the opening and closing of the answer valves are controlled by air cylinders and the like.

The structure of this embodiment has been described above, and its operation will be explained below.

In the dewatering device of this embodiment, the source in the hopper 1 is connected to the tank 3.
For example, when the intake valve 31 is opened and the source water is taken into the tank 33, the intake valve 32 is closed and the pressurizing valve 44 is opened. Then, compressed air is supplied into the tank 34 to dehydrate the contained source water. In the dehydration process, as in the previous embodiment, when compressed air passes through the source and passes through the porous casing 35 - filter cloth 36 - porous filter cloth cover 37, it is dehydrated as a dew-like filtrate and collected in the filtrate tray 45. When the dehydration process of the tank 34 is completed, the pressurizing valve 44 is closed, the atmosphere release valve 44° is opened, and the discharge valve 39 is opened to allow the waste inside the tank 34 to fall and be discharged by its own weight. The intake valve 31 is closed to stop supplying the source water to the tank 33, and the tank 33 is closed.
The dehydration process of the source water supplied to the water source is ready to start.

When the discharge of the treatable material in the tank 34 is completed, the discharge valve 39
, the intake valve 32 is opened to supply the source water into the tank 34, the atmosphere release valve 43° is closed, the pressurizing valve 43 is opened, and the dehydration process of the source water in the tank 33 is started.

And by repeating this action, you can achieve almost continuous dehydration!
This means that A-burying can be done.

The present embodiment configured for this purpose can perform high-rate dehydration treatment like the first embodiment described above, and also has the effect of simplifying the structure because there is no rotating part like the first embodiment.

In addition, in this embodiment, the dewatered mud is allowed to fall from the tank by its own weight, so if the internal shape of the tank (the internal shape of the porous casing 35) is made into a truncated conical shape that widens at the bottom, the treatment efficiency will be improved. Improves self-weight falling properties.

In addition, two tanks are used for alternate operation,
As in Example 1, the number of units may be one, or three or more units may be provided and operated continuously.

[Effects of the Invention] As explained above, according to the present invention, since the water contained in the mud is blown out using compressed air, highly efficient dewatering can be performed, and when the dewatering process is performed while stirring the mud, It has the effect of uniformly dewatering muddy soil.

Furthermore, the present invention requires the addition of a polymer flocculant, and there are no limitations on where the dewatered mud can be disposed of.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway side view showing Embodiment 1 of the dewatering device according to the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG. Figure 4 is a diagram explaining the behavior of water in mud, Figure 5 is Example 2.
FIG. 1...Hopper 2.33.34-...Tank 3...Lower tank part 4...Upper tank part 5
...Joint member 6...Joint bin 7.
...Screw shaft drive motor 8...Screw shaft chain wheel 9.35...
Porous casing 10.36...Filter cloth 11, 37...Porous filter cloth cover 12...Screw shaft air nozzle 13...Rotary seal 14...Screw blade 15.31.32...Intake valve 16...Discharge pipe 17...Atmospheric release pipe 1
8...Filtrate discharge pipe 19...Filter cloth cleaning pipe 20
．． 43.44... Pressure valve 21... Filtrate tank opening/closing cylinder and 4 others Figure 3 37-1

Claims (1)

[Claims] 1. It has an opening for supplying mud and a discharge opening for discharging dehydrated mud, and a filter cloth is fixed to the inner surface of the side plate of the tank at approximately the lower half in the longitudinal direction with a gap between them. At least one mud dewatering tank, a hopper that supplies mud to the mud dewatering tank, and a mud intake valve that opens when mud is supplied to enable the mud from the hopper to be supplied to the mud supply opening of the tank. and a mud discharge valve that opens when dewatering mud is discharged and allows the mud to be discharged from the discharge opening to the outside of the tank. A screw shaft is installed in the horizontal direction that agitates and transfers the mud that is spouted from a number of nozzles through the tank while rotating, and the water released from the mud is drained through the filter cloth to the outside of the tank by the pressurized air jetted from the screw shaft. A dehydration device characterized by: 2. Claim 1, wherein the tank side plate of substantially the lower half of the tank is configured to be openable and closable with respect to the tank body.
The dehydration device described in . 3. A hopper for supplying mud, at least one vertically arranged mud dewatering tank provided at the bottom of the hopper and having a filter cloth on the circumference, and a valve that opens when mud is supplied to drain water from the hopper to the tank. A mud intake valve that allows mud to be supplied; a mud discharge valve that opens when dewatered mud is discharged to allow the mud to be discharged outside the tank; and a filtrate tray that receives the filtrate that has passed through the filter cloth of the tank. and a pneumatic pipe through which compressed air passes through the pipe and is ejected from a large number of nozzles during dehydration processing, and the water released from the mud is drained into the filtrate pan through the filter cloth by the pressure air ejected from the pneumatic pipe. Dehydration equipment.