JPS6134007Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a filtration device in which a filtrate collecting portion is covered with a filter net.

The present inventor previously developed a filtration device of this type, which includes a filtration water collection section located in a filter layer made of granular filter media, a filter net covering the water collection section main body, and a water collection section main body. We proposed a filtration device consisting of a spiral wire member interposed between a filter mesh and a spiral wire member. In this filtration device, the filter layer is cleaned by the agitation of the granular filter media, but when the granular filter media is agitated, the inner surface of the filter network and the wires are washed away by the accompanying agitation of the filter net itself. The members are rubbed together, and at the same time, the outer surface of the filter net and the granular filter medium are rubbed together, so that deposits on the inner and outer surfaces of the filter net are dissociated and removed.

However, since this filtration device uses a spiral wire member, the filtrate collecting portion lacks robustness and durability. In addition, as shown in FIG. 1, the filter net a sometimes becomes entangled with the wire member b, which hinders the movement of the filter net a during cleaning of the filter layer.

Therefore, this invention proposes a filtration device aimed at eliminating the drawbacks of the filtrate water collecting section of the previous filtration device.

Hereinafter, the filtration device according to this invention will be explained based on an optimal embodiment.

In the figure, reference numeral 1 denotes a filter tank, and in this filter tank 1, granular filter media for filtering raw water are deposited to form a filter media layer 2.

As the granular filter medium, for example, filter sand made of fine and coarse mixed sand is used.

In the figure, 3 is the first raw water chamber, 4 is the second raw water chamber formed by the raw water chamber forming plate 5, and 6 is the first raw water supply branching upward from the raw water supply pipe 7 and communicating with the first raw water chamber 3. A pipe 8 is a second raw water supply pipe that branches downward from the raw water supply pipe 7 and communicates with the second raw water chamber 4 .

Raw water is supplied to the first raw water chamber 3 and the second raw water chamber 4 through the first raw water supply pipe 6 and the second raw water supply pipe 8, respectively.

9 in the figure is a raw water pipe provided on one side of the filter medium layer 2.

The lower end of this raw water pipe 9 is closed, and the upper end is open within the first raw water chamber 3.

Further, a small number of raw water distribution ports 10 are formed in the middle thereof, and each raw water distribution port 10 is provided with a check valve 11 for preventing the inflow of granular filter media.

The raw water flow path forming plate 12 shown by the reference numeral 12, that is, the raw water flow path forming plate 12 extending spirally along the inner wall of the filtration tank 1 has check valves 11 in the middle thereof.
passing through the part. Raw water flows into a series of raw water channels 13 formed by the raw water channel forming plate 12 through the check valves 11 of the series.

In addition, the upper and lower ends of the raw water flow path forming plate 12 are the first
Openings are made into the raw water chamber 3 and the second raw water chamber 4, respectively, and raw water also flows into the raw water channel 13 from the openings at the upper and lower ends thereof.

Note that, for convenience, the raw water flow path forming plate 12 in the illustrated example is vertically spirally arranged at equal intervals. However, in reality, the raw water flow path forming plate 12 may have different spacing due to its deformation, or if it were spirally regular, a part of the raw water flow path forming plate 12 that should be located at the upper level may be located at the lower position. There are cases where it does.

In addition, the raw water flow path forming plate 12 in the illustrated example has a semicircular cross-sectional shape and a circular spiral;
The cross-sectional shape may be arbitrary, such as a mountain shape, a planar shape, or an angular spiral shape.

In addition, the series of raw water channels 13 may be formed by connecting one ends of two or more raw water channel forming plates 12, instead of using a series of one raw water channel forming plate 12.

Returning to FIG. 2, explanation will be given.

In the figure, reference numeral 14 denotes a drainage water collection section provided approximately at the center of the raw water flow path forming plate 12.

The drainage water collection section 14 includes a water collection section main body 18 having a groove 16 provided on the outer circumferential surface 15 and a water collection port 17 bored in the groove 16;
It is comprised of a filter net 19 that covers the water collection section main body 18 and whose inner surface slides into contact with the outer peripheral surface 15 of the water collection section main body 18 when cleaning the filter medium layer 2. The water collecting portion main body 18 is connected to a drainage pipe 20 extending outside the filtration tank 1. The filter net 19 is designed to loosely cover the groove portion 16 during raw water filtration, that is, the filter net 19 covers the entire surface of the groove portion 16 due to the negative pressure suction action of the water collection port 17 of the water collection portion main body 18. It is coated so that it does not stick tightly and is configured to have a larger passage area for filtrate. In addition, the slack covering of the filter net 19 functions appropriately to shake the filter net 19 itself during cleaning of the filter medium.

In addition, the grooves 16 in the embodiment are grooves, and several grooves are provided around the outer peripheral surface 15 of the water collecting section main body 18 at predetermined intervals. It may be formed by a continuous groove 16 by spirally surrounding the water collecting part body 15, or as shown in FIG.
A required number of depressions 16' having an arbitrary shape may be formed on the outer circumferential surface 15 of the groove 16, and the depressions may be used as the groove portions 16.

In the figure, 21 is an air supply pipe used when cleaning the filter medium layer.

This air supply pipe 21 is connected to an air jet pipe 22 arranged in an annular manner below the filter medium layer 2 .

The air ejection pipe 22 blows the air supplied from the air supply pipe 21 onto the filter medium layer 2 to clean the filter medium layer.

Similarly, 23 in the figure is a separator chamber used when cleaning the filter medium layer.

This separator chamber 23 is provided in the first raw water chamber 3 and has the following configuration, and prevents granular filter media mixed in the wastewater washing water from flowing out. An inlet 24 through which the sewage washing water in the first raw water chamber 3 flows in so as to generate a spiral flow that gradually descends along the inner circumferential wall when cleaning the filter medium layer, and a sewage washing water discharge pipe 25 corresponding to the inlet 24. An outflow port 26 that communicates with the outside of the filtration tank 1 through an outlet 26 is provided vertically at approximately the center and has a required thickness to allow the reversed flow of the descending swirling flow to rotate upward along the peripheral wall and be discharged from the outflow port 26. A rod-shaped body 27, a granular filter media outlet 2 provided at the bottom of the hopper and opened and closed by a valve 28.
Consists of 9.

The valve 28 in the separator chamber is formed of a spherical float valve that is biased in the valve closing direction by buoyancy, and is provided with a mesh basket 30 for preventing the valve 28 from escaping.

In addition, 31 in the figure is the first valve of the raw water supply pipe 7;
32 is the second valve of the first raw water supply pipe 6, 33 is the third valve of the second raw water supply pipe 8, and 34 is the drainage pipe 20.
, 35 is the fifth valve of the waste water washing water discharge pipe 25 , and 36 is the sixth valve of the air supply pipe 21 .

Next, the action will be explained.

First, we will discuss the filtration effect of raw water.

Open the first valve 31, the second valve 32, the third valve 33, and the fourth valve 34, and open the fifth valve 35,
The sixth valve 36 is closed, and the raw water is caused to flow from the raw water supply pipe 7 into the first raw water chamber 3 and the second raw water chamber 4 via the first raw water supply pipe 6 and the second raw water supply pipe 8.

At this time, the granular filter media in the vicinity of the second raw water chamber 4 is pushed away by the water pressure flowing into the filter media layer 2 from the lower opening of the second raw water supply pipe 8, and an amorphous cavity is formed in the lower part of the raw water chamber forming plate 5. Formed by arising.
The raw water that has flowed into the first raw water chamber 3 and the second raw water chamber 4 enters the filter layer 2 from above and below, is filtered by the upper and lower portions of the filter layer 2, and heads toward the filtrate collection section 14. In addition, the raw water that has flowed into the first raw water chamber 3 and the second raw water chamber 4 flows into the raw water flow path 13 from the upper and lower end openings of the raw water flow path forming plate 12, and from this raw water flow path 13, the filtrate is collected. Water floods towards the water portion 14 and is filtered on the circumferential side of the filter medium layer 2.

Similarly, the raw water that has flowed into the first raw water chamber 3 flows into the raw water pipe 9 from the upper end opening of the raw water pipe 9, and then passes through the raw water distribution port 10 of the raw water pipe 9 to the raw water flow path forming plate 12. The raw water flows into the raw water flow path 13,
Water flows from this raw water flow path 13 toward the filtered water collection section 14 and is filtered on the circumferential side of the filter medium layer 2.

Then, the filtrate filtered on the upper, lower, and peripheral sides of the filter medium layer 2 reaches the filtrate collecting section 14 . At this time, the filtered water is collected into the water collecting section main body 18 through the filter net 19, thereby preventing the granular filter medium from flowing out and clogging the water collecting port 17.

Further, as described above, the filter net 19 of the sewage collection section 14 is configured to cover the entire surface of the groove section 16 so as not to come into close contact with it, so that the area through which the sewage passes through the section of the sewage collection section 14 becomes large. Therefore, it is possible to improve the filtration speed. Furthermore, the water collection section main body 18
Since it consists of a groove 16 and a water collection port 17 formed in the groove 16, there is no risk that the filter net a will become entangled, unlike in the case where the conventional wire member b is used.

Under such an effect, the water collection body 18
The filtered water flows out through the drainage pipe 20 to the outside.

Next, the cleaning action of the filter medium layer will be described.

Open the first valve 31, third valve 33, fifth valve 35, and sixth valve 36, and open the second valve 32,
The fourth valve 34 is closed, raw water is supplied as cleaning water to the bottom of the filter layer 2 from the second raw water supply pipe 8, and at the same time air is supplied to the bottom of the filter layer 2 from the air jet pipe 22.

By supplying this washing water and air, the granular filter medium is agitated and the adhered substances are dissociated.

When cleaning the granular filter medium, the granular filter medium and the filter net 19 are rubbed together due to the agitation of the granular filter medium in the filtrate water collection section 14 and the accompanying agitation of the filter net 19, and the outer surface of the filter net 19 is rubbed together. Adherents such as turbidity are dissociated and removed. In addition, as the filter net 19 moves, the filter net 19 also rubs against the outer circumferential surface 15 of the water collection section main body 18, and the deposits on the inner surface of the filter net 19 are also dissociated and removed.

Even in this case, there is no risk that the filter net 19 will become entangled with the grooves 16 or the like of the water collection section main body 18.

By introducing such washing water, the filtration tank 1
When the water level rises and reaches the inlet 29 of the separator chamber 23, the dirty water washing water partially mixed with granular filter medium flows into the separator chamber 23. The inflowing sewage cleaning water turns into a swirling flow 37 along the inner circumferential wall of the separator chamber 23 and descends while swirling.

At this time, the granular filter medium mixed in the wastewater washing water is separated by centrifugal force and is deposited at the bottom of the separator chamber 23 while rotating along the inner circumferential wall.

During this washing, the valve 28 closes the granular filter medium outlet 29 by its buoyancy.

Then, the descending sewage washing water is reversed at the bottom, turns into an upward rotating flow 38 along the peripheral wall of the rod-shaped body 27, and is discharged to the outside from the sewage washing water discharge pipe 25 through the outlet 26.

Incidentally, since the rod-shaped body 27 of the upward rotational flow 38 is formed to have a required thickness, the rotational diameter of the upward rotational flow 38 is larger than the thickness of the rod-shaped body 27.

Therefore, even if a part of the granular filter media that has settled and accumulated at the bottom of the separator chamber 23 rolls up together with the ascending rotational flow 38, the centrifugal force corresponding to the rotational diameter is acting on the ascending rotational flow 38, so that the part of the granular filter media that has settled and accumulated at the bottom of the separator chamber 23 is not lifted up. It is shaken out, moves to the swirling flow 37 side, is further separated, and settles and accumulates at the bottom.

Therefore, the granular filter medium mixed in the wastewater washing water does not flow out from the outlet 26.

After these combined cleanings with water and air, a cleaning finish is performed using only cleaning water.

On the other hand, when the granular filter material that has settled and accumulated at the bottom of the separator chamber 23 reaches a certain weight, its own weight causes the valve 28 to open against the valve closing force due to buoyancy, and the granular filter material is transferred to the granular filter material outlet 28. It is further reduced to the filter medium layer 2.

Further, air during combined cleaning is exhausted from the wastewater washing water discharge pipe 25 through the outlet 26 together with the wastewater washing water.

In the filtration device according to the invention constructed as described above, the water collection main body 18 is constituted by the groove 16 and the water collection port 17 bored in the groove 16, so it is different from the conventional spiral wire member. It has the advantage that the drainage water collection part 14 is more robust and has excellent durability than the one using a water filter. In particular, this advantage is most important because the filtrate water collecting section 14 is located in the filter layer 2, so it is under heavy pressure from the filter layer, and the filter net 19 is shaken when cleaning the filter layer. This is extremely meaningful as it requires robustness and durability.

In addition, since the water collection body 18 does not use a member spaced apart from the outer circumferential surface of the water collection body, that is, a wire member, unlike conventional ones, the filter net 19 may become entangled with the grooves 16, etc. There is no risk of that happening. Therefore, there is an advantage that the filter net 19 can be properly moved and cleaned without causing any trouble in the movement of the filter net 19 when cleaning the filter medium layer.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the main part of a conventional filtration device, Fig. 2 is a cross-sectional view of the filtration device according to this invention, Fig. 3 is an enlarged perspective view of the main part of Fig. 2, and Fig. 4 is the main body of the water collection section. It is a partial perspective view which shows the other example of a structure. Main symbols in the figure: 2...filter layer, 14...filter water collection section, 15...outer peripheral surface, 16...groove, 17...
... Water collection port, 18 ... Water collection section body, 19 ... Filter net.

Claims (1)

[Claims for Utility Model Registration] A filtrate collecting section 14 in the filter layer 2 made of granular filter media.
In the filtration device, the filtration water collection section 14 includes a groove 16 provided on the outer circumferential surface 15 and a groove 16 provided on the outer circumferential surface 15. a water collection part main body 18 having a water collection port 17 bored in the water collection part 16;
A filtration device comprising a filter net 19 that covers the water collection body 18 and whose inner surface slides into contact with the outer peripheral surface 15 of the water collection body 18 during cleaning of the filter layer 2.