JPS5855802B2 - Moving bed filtration equipment - Google Patents

Description

[Detailed description of the invention] This invention relates to a moving bed type filtration device.

Conventional devices of this type are configured such that a filtration tank is installed diagonally at the bottom of the raw water tank, and the raw water is passed downward from the top of the filtration tank to a water collection device installed at the bottom of the tank. A filter media discharge device is provided at the lower end of the filtration tank, and by operating this device, the entire filter media is pushed up and the contaminated filter media in the upper layer is discharged into the raw water tank.

However, since it is necessary to push up the entire filter medium when discharging the contaminated filter medium, the conventional apparatus described above requires a large thrust force in the discharge device.

Furthermore, since the filtration tank is provided diagonally, the filter medium in the upper layer is likely to collapse, resulting in uneven thickness of the filter medium layer, which reduces filtration efficiency.

On the other hand, there is also a device in which the filtration tank is installed vertically below the raw water tank.

Although this device eliminates the disadvantage of the above device in that the upper layer of the filter media tends to collapse, it has the same problem as the above device in that the entire filter media must be pushed up to discharge contaminated filter media. It was something.

A first object of the present invention is to provide a moving bed type filtration device that can move and discharge only contaminated filter media without moving the entire filter media.

A second object of the present invention is to provide the above-mentioned device in which the remaining filter media can easily move to fill the voids left after the contaminated filter media is discharged.

A third object of the present invention is to provide the above-mentioned device, which can clean the perforated plate provided on the raw water inflow side of the filtration tank at the same time as discharging the contaminated filter medium, thereby preventing clogging of the perforated plate.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in Fig. 1, the device of the present invention has a filtration tank 2 installed on the earthen wall of a sealed raw water tank 1, a perforated plate 3 provided at the lower end of the filtration tank 2, and a perforated plate 3 on the upper side wall. A water collection device 4 is provided.

The lower part of the filtration tank 2 provided with the perforated plate 3 is located inside the raw water tank 1, and the upper part provided with the water collection device 4 is located outside the raw water tank 1.

As shown by the arrow in the figure, the raw water flows from the raw water flow pipe 19 into the raw water tank 1, passes through the perforated plate 3, flows into the filtration tank 2, passes through the filter medium A from bottom to top, and is collected. water device 4
It is designed to reach.

Discharge ports 5 and 5' for highly contaminated filter media (hereinafter simply referred to as contaminated filter media A') are provided at opposing positions on the lower side wall of the filtration tank 2, and the discharge ports 5 and 5' are flexible. It is closed with opening/closing lids 6, 6' made of a suitable material.

However, the filter medium A filled in the filtration tank 2.

Since A1 has a certain degree of bonding force, it will not naturally fall from the tank 2 into the raw water tank 1 even if the opening/closing lids 6, 6' are not provided.

The device 7 for discharging contaminated filter media A' consists of a cylinder 8 attached to the side wall of the raw water tank 1 and a push-out plate 10 attached to the tip of the piston rod 9.

The piston rod 9 freely passes through the side wall of the raw water tank 1 in a liquid-tight state, and further passes through the lid 6'.

A push-out plate 10 is attached to the tip of the piston rod 9.

The extrusion plate 10 moves forward and backward between the discharge ports 5 and 5' while sliding on the perforated plate 3.

An ejector 11 is provided at the lower end opening of the raw water tank 1, and the ejector 11 and the upper part of the filtration tank 2 are connected by a filter medium transfer pipe 12. A device 13 is provided.

A water collection device 4 of the filtration tank 2 is connected to a discharge pipe 14 for treated water, and this pipe 14 reaches a treated water tank 16 via a control valve 15.

The treated water stored in this water tank 16 is transferred to the ejector 11.
In this case, a pipe 18 with a pressure water pump 17 interposed therebetween is provided between the water tank 16 and the ejector 11.

Note that 20 in FIG. 1 is a discharge pipe for discharging cleaning wastewater out of the system out of the filter medium and cleaning wastewater washed by the filter medium cleaning device 13.

Since the device shown in Fig. 1 is constructed as described above, raw water is pressurized and passes through the filtration tank 2 in an upward flow, so that the filter medium A in the lower layer in the filtration tank 2 is most likely to be contaminated. That will happen.

Therefore, when the above-mentioned discharge device 7 is activated to discharge the contaminated filter medium A', the lid 5 is pushed open and the contaminated filter medium A9J'' is pushed out by the extrusion plate 10, as shown in FIG. , falls into the raw water tank 1.

The discharge device 7 stops with the contaminated filter medium A' pushed out.

In the voids created after the contaminated filter media No. A is discharged, the entire filter media with a relatively low degree of contamination in the upper layer descends to fill the voids.

If filtration continues in this state and the filter medium in the lower layer becomes contaminated, the extrusion plate 10 of the discharge device 7 is moved back and the contaminated filter medium is discharged from the discharge port 5' on the opposite side.

Note that the ejecting device 7 may be immediately retreated to its original state after extruding the contaminated filter medium A' with its extrusion plate 10, but this may result in scraping out a portion of the filter medium that has fallen from the upper layer when retreating. , which is not very desirable.

While the contaminated filter medium A' is discharged as described above, the contaminated filter medium A' is sent from the ejector 11 to the cleaning device 13, where the cleaned filter medium is supplied from the upper part of the filtration tank 2, thereby stopping the device. The filter medium can be discharged and supplied without any trouble.

Next, in the embodiment shown in FIG. 3, the filtration tank 2 has a tapered shape that widens at the bottom, so that the upper layer filter material can easily fall into the gap created after the contaminated filter material A' is discharged. It has become.

Since the other configurations are the same as those described above, the same parts are given the same reference numerals, and the explanation thereof will be omitted.

FIG. 4 shows another embodiment of the discharge device T, in which the lower surface of the extrusion plate 10 is a brush surface.

By bringing this brush 10a into contact with the upper surface of the perforated plate 3, the perforated plate 3 is cleaned when the extrusion plate 10 is moved, and clogging thereof is prevented.

The embodiment shown in FIGS. 5 and 6 uses a discharge device 7' having a horizontally swinging pusher plate 10'.

In this case, the discharge port 5a is provided over the entire circumference of the lower part of the filtration tank 2, and the extrusion plate 10 is moved horizontally so as to slice the lower end of the filtration tank 2, and removes the contaminated filter medium A'.
will be pushed out.

In the case of this embodiment, the filter media A and A are exposed at the discharge port 5a, but as described above, the filter media have a certain degree of cohesive strength, so they will not fall.

The lower surface of this extruded plate 10' may be a brush surface as described above, or the filtration tank 2 may be tapered as described above.

As described above, in order to discharge contaminated filter media using the device of the present invention, it is only necessary to discharge only the contaminated filter media in the lower layer of the filtration tank without moving the entire filter media, and the remaining filter media falls at a scale.

Therefore, the thrust required to eject contaminated filter media may be significantly lower than in conventional devices.

In addition, when the filtration tank is tapered to widen downward, the remaining filter media can reliably fall under its own weight into the voids created after the contaminated filter media is discharged, thereby filling the voids.

Furthermore, if the lower surface of the extruded plate is a brush surface, the perforated plate can be cleaned at the same time as the filter medium is extruded, so that clogging thereof can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of the device of the present invention, Fig. 2 is a sectional view of the above device in a state where contaminated filter media is discharged, Fig. 3 is a sectional view showing another example of the device, and Fig. 4 is an extrusion FIG. 5 is an enlarged sectional view showing an example of the use of the plate, FIG. 5 is a sectional view showing another example of the device, and FIG. 6 is a cross-sectional plan view of the device shown in FIG. 1... Raw water tank, 2... Filtration tank, 3... Perforated plate, 4... Water collection device, 5
, 5', 5 a...Exhaust port, γ...
・Discharge device, 10, 10'... Extrusion plate, 10
a...Brush.

Claims (1)

[Claims] 1. A filtration tank is provided above the raw water tank, and
A water collection device is installed at the top of the filtration tank to achieve upward flow filtration, and the filter media outlet provided outside the bottom of the filtration tank is located inside the raw water tank, and the extrusion plate for the filter media is installed at the bottom end of the filtration tank. A moving bed type filtration device, characterized in that the moving bed type filtration device is provided on the upper surface of a raised perforated plate so as to be slidably in contact with the filter medium outlet toward the filter medium outlet, and a filter medium transfer pipe after cleaning is connected to the upper part of the filtration tank. 2. The moving bed type filtration device according to claim 1, wherein the filtration tank is formed in a tapered shape with a bottom end. 3. The moving bed type filtration device according to claim 1 or 2, wherein the discharge ports are provided at two locations at the bottom of the filtration tank, and a push-out plate is provided between the two discharge ports. 4. The moving bed type filtration device according to claim 1 or 2, wherein the discharge port is provided all around the lower part of the filtration tank, and the extrusion plate swings relative to the discharge port. 5. Claims 1, 2, 3, or 4, wherein the lower surface of the extruded plate has a brush surface that slides into contact with the perforated plate.
The moving bed type filtration device described in Section.