JPS6249088B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cake peeling device for a filtration/concentration device, and in particular to supplying pressurized air containing water, that is, pressurized air containing fine water droplets, into the filtration chamber of a filter suspended within the sludge chamber. The present invention relates to a cake peeling device for a filtration and concentration device that removes cake attached to a filter cloth net.

Water sludge discharged from water supply plants generally contains 90%
Before sludge treatment, water sludge is introduced into a filtration tank and water is filtered out using a filter to reduce the water content of water sludge and remove the sludge. It is concentrated and then discharged. In the above-mentioned filter, the whole or a part of the filtration chamber is covered with a filter cloth net, and the filtered water is discharged through the filter cloth net through the filtrate discharge pipe, and the dehydrated thickened sludge is sent to the filtration tank. It is designed to be discharged from the bottom.

However, there is a problem in that cake adheres to the filter cloth net during use, resulting in a decrease in filtration performance.

In order to remove this cake on the filter cloth, conventionally, compressed air was blown into the filtration chamber of the filter, but if the cake adhering to the filter cloth was extremely thin, it could not be removed. If compressed air is blown into the sludge when it is incomplete or the filter is immersed in the sludge, the sludge will be agitated and the peeled cake will be crushed, resulting in a decrease in the concentration and amount of cake to be recovered. I had a problem with it.

Therefore, the object of the present invention is to provide a filtration concentration method that uses water-containing pressurized air to reliably peel off the cake attached to a filter cloth immersed in sludge, restore filtration performance, and maintain filtration. An object of the present invention is to provide a cake peeling device.

In order to achieve the above object, the present invention provides a filter in which a filter having a filter cloth surrounding the filtration chamber is disposed in a sludge chamber of a filtration tank, and water in the sludge is filtered and removed into the filtration chamber. A water-containing pressurized air supply pipe is connected to the filtration chamber of the filter, and a water-containing pressurized air generator is connected to the supply pipe.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a cake peeling device of a filtration and concentration device according to the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 indicates a filtration tank, and in this filtration tank 1, a sludge chamber 6 is surrounded by a front plate 2, a rear plate 3, and a pair of side plates 4, 5, which are arranged in parallel in a vertical plane. It is formed. The front plate 2 and the rear plate 3 are each bent inward in a dogleg shape so that their lower parts are symmetrical with respect to the center, forming a tapered lower sludge chamber, the end of which is closed by the bottom plate 7. has been done. Note that the upper part of the sludge chamber 6 has an opening 8 through which sludge can be charged.

A cake discharge pipe 10 is provided on the bottom plate 7 of the filtration tank 1.
One end is connected to this cake discharge pipe 10.
A discharge pump 11 is installed on the pipe, and a discharge valve 12 is further installed on the suction side.

A rectangular plate-shaped filter 14 is suspended in the sludge chamber 6, and as shown in FIG. 2, this filter 14 has a convex cross section and a frame-like shape. From both sides of the spacer frame 15, the filter cloth nets 16, 1
7 and then frame plates 18 and 1 from the outside.
A filter chamber 20 is formed between the filter cloth nets 16 and 17. It is preferable that the filter cloth net is stretched over both sides of the spacer frame 15 as shown in the figure, but it may also be stretched across the opening of a box-shaped frame that is open on only one side.

Further, one end of a filtrate discharge pipe 21 is connected to the lower central portion of the filter cloth net 16 or 17, and a drain valve 22 is incorporated in the middle of this filtrate discharge pipe 21.

According to the present invention, the filter cloth net 16 of the filter 14
One end of a water-containing pressurized air supply pipe 23 is connected to the upper center of the front plate 2.
A supply source of compressed air, such as a compressor 24, is connected to the tip of the pipe, and an air valve 25 is connected to the supply pipe 23.
is incorporated.

Further, a water suction pipe 26 branches off from the middle of the supply pipe 23, and this water suction pipe 26 is immersed in water stored in a water storage tank 27. A water supply pipe 28 is connected below this water tank 27, and a water supply valve 29 is installed on this pipe. The water storage tank 27 and the supply pipe line 23 are connected by a communication pipe 31 having a valve 30 disposed on the pipe line, so that a part of the compressed air can be supplied above the water surface of the stored water. .

Since the present invention is configured as described above, clean water sludge is charged into the sludge chamber 6 from above the opening 8,
When the drain valve 22 is open, the solid particles are blocked by the filter screen, and only water seeps into the filtration chamber 20 through the filter screens 16 and 17 and is discharged through the filtrate drain pipe 21. As filtration progresses over a long period of time, cake adheres to the surface of the filter cloth nets 16 and 17.
When the filtration performance decreases, open the discharge valve 12,
After driving the discharge pump 11 to discharge the unconcentrated sludge in the sludge chamber 6, the discharge valve 12 and the drain valve 22 are fully closed. Next, open the air valve 25,
The compressor 24 is driven to supply compressed air into the supply pipe line 23. Then, due to the increase in the flow velocity of the air, the inside of the water suction pipe 26 becomes negative pressure, and the water in the water tank 27 is sucked out and atomized to become water-containing pressurized air, which is ejected into the filtration chamber 20 of the filter 14. When the water-containing pressurized air is blown into the filtration chamber 20 in this way,
Since the filter cloth nets 16 and 17 expand and open their meshes, they blow out water-containing pressurized air into the sludge chamber, so that the cake adhering to the filter cloth nets 16 and 17 is transferred to the surface where the air is blown out and the filter cloth is attached. It is easily peeled off from the filter cloth by the penetration of water.

FIG. 3 shows another embodiment of the present invention, in which the same parts as in FIG. 1 are denoted by the same reference numerals. This embodiment is an embodiment in which a pump is used in place of the water tank 27 and water suction pipe 26 in the previous embodiment to supply water directly into the compressed air. That is, there is a water supply pipe 3 in the middle of the supply pipe line 23.
2 and connect the other end of this water supply pipe 32 to the water tank 33.
This is an example in which a pump 34 and a water supply valve 35 are installed in the middle of the water supply pipe 32. In such an embodiment, the compressor 24 is driven to open the air shield valve 25, and at the same time, the pump 34 is driven to open the air shield valve 35 to mix and supply compressed air and water. Hydrous pressurized air is supplied into the filtration chamber 20 through the pipe line 23, and the same effects as in the embodiment described above can be expected. In this embodiment, it is possible to adjust the humidity of the water-containing pressurized air by appropriately adjusting the opening degree of the air shield valve 25 and the opening degree of the water supply valve 35.

As described above, according to the present invention, when cake adheres to the filter cloth of the filter and the filtration performance deteriorates, pressurized air containing water is blown into the filtration chamber of the filter. Moisture-containing pressurized air is uniformly blown out from the inside of the filter cloth toward the sludge chamber, causing the filter cloth to swell, allowing water to permeate between the surfaces that adhere to the filter cloth and ensuring that the cake is removed from the filter cloth. It becomes possible to peel it off. Therefore, by repeating this intermittently, the filtration performance of the filter can be maintained over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing one embodiment of a cake peeling device of a filtration and concentration device according to the present invention, FIG. 2 is a perspective view showing a partially cut away filter, and FIG. FIG. 1 is a perspective view showing a cake peeling device according to an embodiment. 1... Filter tank, 6... Sludge chamber, 10... Cake discharge pipe, 11... Discharge pump, 14... Filter,
16, 17...filter cloth net, 20...filtration chamber, 23...
... Supply pipe line, 24 ... Compressor, 25 ... Air shield valve, 26 ... Water suction pipe, 27 ... Water tank,
28... Water supply pipe, 29... Water supply valve.

Claims (1)

[Scope of Claims] 1. A filter in which a filtration chamber is surrounded by a filter cloth net is disposed in a sludge chamber of a filtration tank, and water in the sludge is filtered and removed into the filtration chamber,
A cake peeling device for a filtration/concentration device, characterized in that a water-containing pressurized air supply pipe is connected to the filtration chamber of the filter, and a water-containing pressurized air generator is connected to the supply pipe. 2. In the cake peeling device according to claim 1, the water-containing pressurized air generator feeds the compressed air flow from the compressor into the supply pipe, and connects the compressed air flow with the compressed air flow in the middle of the pipe. A cake peeling device characterized in that a water suction pipe that generates negative pressure is connected, and the tip of the water suction pipe is immersed in water in a water tank. 3. The cake peeling device according to claim 1, characterized in that the compressed air flow from the compressor and the water supplied from the water storage tank are mixed and supplied into the supply pipe line. Cake peeling equipment.