JPH022406Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a continuous filtration device, and particularly to a filtration device suitable for preventing deterioration of treated water quality.

As shown in FIG. 1, a conventional device of this type includes a vertical water-permeable inner cylinder 12 formed of inclined plates 11A arranged in a multi-stage manner and having a water sprinkling section 3 inside.
and a vertical water-permeable external cylindrical body 1 formed by multi-stage inclined plates 11B and having a water collecting section 4 on the outside.
3, and an air lift pipe 7 for transporting the suspended solids trapping material, which extends from the bottom of the filter tower 1 through the internal cylinder 12 and reaches upward. In such a device, the space between the inner cylinder 12 and the outer cylinder 13 is filled with a material (layer) 2 such as sand (this material layer is held between the inclined plates 11A and 11B),
Overtreatment of the water to be treated is performed through this material layer.

At this time, the water to be treated is led to the water spraying section 3 after passing through the supply pipe 5, and then sent into the material layer 2 through the mutual gap between the inclined plates 11A. The treated water sent in this way flows horizontally within the material layer, during which suspended solids are removed, and is then collected in the water collection section 4 through the mutual gap between the inclined plates 11B. Then, it is discharged to the outside of the system through the drain pipe 6.

On the other hand, the material layer 2 that has captured the suspended solids moves continuously in the direction of gravity under the suction action of the air lift tube 7, which will be described below. The suspended solids trapping material layer that has finally reached the inlet of the air lift pipe 7 is stirred by the air introduced through the air supply pipe 8 and rises inside the air lift pipe 7, and is placed in the upper part of the overcoat 1. The washed material is discharged into the cleaning tank 9, where it is reused after cleaning. Note that the waste liquid after the cleaning is discharged to the outside of the system through the discharge pipe 10.

In this way, in conventional equipment, the water flow surfaces of each cylinder have a vertical structure, so even if it is desired to increase the amount of water to be treated, it is only necessary to increase the height of the tower, and therefore the site It has the advantage of not requiring an increase in area. However, because the material layer continuously moves in the direction of gravity, the amount of suspended solids attached to the lower material layer is greater than that of the upper material layer, and as a result, the quality of treated water deteriorates as the tower height increases. This causes the problem of deterioration.

The purpose of this invention is to eliminate the drawbacks of the prior art described above, and even when increasing the amount of treated water,
An object of the present invention is to provide a continuous filtration device that can prevent deterioration of treated water quality without increasing the site area.

In order to achieve the above object, this invention consists of a water-permeable cylindrical body formed by arranging inclined plates in multiple stages, which are arranged in double form along the vertical direction, and between the cylindrical bodies is a material-filled section. The inner and outer parts are a water sprinkling part to horizontally supply water to be treated to the material filling part and a water sprinkling part to receive excess water, and also enable continuous movement of the material in the direction of gravity and regeneration associated with this. In a continuous filtration device, the angle formed by the horizontal plane and the line connecting the upper and lower ends of the adjacent inclined plates is arranged such that the multi-stage inclined plates constituting the cylinder corresponding to the water spraying section are used to deposit material. It is characterized by being arranged so that the angle of inclination is larger than the maximum angle at which the surface is stable without collapsing when the surface is tilted.

With this configuration, it is possible to flow the material that has captured suspended solids into the water spraying section from the gap between the inclined plates, and to collect this through the air lift pipe, thereby increasing the height of the cylindrical body. Even when the amount of water to be treated is increased, the disadvantage that the quality of the treated water deteriorates due to an increase in the amount of attached turbidity is eliminated. The angle between the line segment between the inclined plates and the horizontal plane must be varied along the vertical direction of the watering area, as long as it is greater than the maximum angle of inclination that will ensure that the surface is stable without collapsing when the material is deposited. However, since prevention of deterioration of treated water quality is achieved more effectively as the lower material with a larger amount of trapped suspended solids is recovered, it is desirable to increase the size of the lower inclined plate.

This invention will be explained in more detail below with reference to embodiments shown in the drawings.

FIG. 2 shows a partially enlarged side cross section of an inclined plate that can be applied in place of the inclined plate 11A of FIG. In this inclined plate 11C, the mutual spacing is set to gradually increase as it goes downward, but such setting can be done as follows.

That is, first, the minimum length L ₀ of the inclined plate necessary to prevent the material from flowing into the sprinkler section 3 is:
As is clear from FIG. 2, it is given by the following equation (1).

L ₀ =p・cosα／(sinα・cosθ＋cosα・sinθ)
...(1) (where p, θ, and α are the values obtained when the lower ends of the inclined plates are aligned along the same vertical line, and are the pitch of the inclined plate, the inclination angle of the inclined plate, and the material deposited, respectively. (This indicates the maximum angle of inclination at which the surface remains stable without collapsing when the surface is tilted.) This L ₀ has the following meaning in comparison with the length L of the inclined plate actually used.

When L ₀ -L≦0: The material does not flow into the water sprinkling section.

When L ₀ −L>0: the material flows into the water spraying section.

When L ₀ −Ln>0 and Ln=L ₁ >L ₂ >L ₃ ...:
As the material becomes L ₁ , L ₂ , L _{3 . .} . , the amount of material flowing into the water sprinkling section increases sequentially.

Therefore, in the above embodiment, it is understood that the length L of the inclined plate may be gradually shortened as it goes downward.

With the inclined plate 11C having such a configuration, the lower the material with a larger amount of trapped suspended solids, the more the material will flow into the water sprinkling section 3. The material after flowing in then falls downward inside the water sprinkling section,
Finally, it is mixed with the material moving downward outside the water spraying section, and then ascends in the air lift pipe 7 in the same manner as in the case of FIG. 1, and is reused after being cleaned in the material cleaning tank 9.

As a result of the above, a reduction in the amount of trapped suspended solids attached to the lower material layer has been achieved, and as a result, even when the tower height is increased to increase the amount of treated water, deterioration of the quality of treated water can be prevented. It becomes possible.

The effects of this invention will be explained in more detail below using specific examples.

Specific example: Under the following conditions, water to be treated with a turbidity concentration of 20 mg/was overtreated.

Slanted plate Water collection part: Incline angle 80°, pitch 100mm, length is _1.5 of the required minimum length L 0 calculated using the formula (1) mentioned above.
Sprinkling section: Incline angle 80°, length 1.0 to 0.8 times the required minimum length L ₀ calculated using formula (1) above,
The height of the cylinder (bed height): 4 m for both the inner cylinder and the outer cylinder Material: Sand with an effective diameter of 1.0 mm (angle of repose is approximately 35°) As a result of treatment, the water collection area The concentration of suspended solids in the collected overwater was less than 2 mg/, and it is clear that this value is significantly improved from the suspended solid concentration of 5 mg/ when the same procedure was carried out except that no material was allowed to flow into the watering section for comparison. It was a long time ago.

Although the above explanation has been made regarding a typical embodiment of this invention, this invention is not limited to this. For example, in the above embodiment, L is calculated based on constant values of p and θ. Find ₀ , this L ₀
Although the procedure for calculating L from the above is used, instead of this, p can be set to an appropriate value from constant values L and θ (the mutual spacing between the inclined plates is constant), and the same effect can be obtained. The key is to set each slope so that the angle formed by the horizontal plane and the line connecting the top and bottom ends of adjacent sloped plates is greater than the maximum slope angle α that will ensure that the surface is stable without collapsing when the material is piled up. By providing inclined plates, material can flow into the water spraying section from between the inclined plates. Furthermore, the cross section of the tower is not limited to a circular shape, and may have any shape including a square or a rectangle. Furthermore, the functions of the inner cylindrical body and the outer cylindrical body can be reversed, and the former can be used as a water collection part and the latter as a water sprinkling part.

As described above, according to this invention, the angle between the horizontal plane and the line connecting the upper and lower ends of the adjacent inclined plates of the multi-stage inclined plates constituting the cylindrical body corresponding to the water sprinkling section allows the material to be deposited. By arranging it so that the angle of inclination is greater than the maximum angle at which the surface remains stable without collapsing when the water is exposed to water, the material that has captured suspended solids, especially the lower material with a large amount of adhesion, flows into the water spraying section, and It becomes possible to recycle and reuse this material well, and it is also possible to reduce the amount of trapped suspended solids attached to the lower material layer. As a result, even when the tower height is increased to increase the amount of treated water, it is possible to prevent the quality of the treated water from deteriorating.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a conventional continuous filtration device, and FIG. 2 is a partially enlarged side sectional view of an inclined plate of a water spraying section according to an embodiment of this invention applicable to the device of FIG. 1... Passing tower, 2... Material layer, 3... Watering part,
4... Water collection section, 7... Air lift pipe, 9... Material cleaning tank, 11A, 11B, 11C... Inclined plate, 1
2...Inner cylinder, 13...Outer cylinder.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) Water-permeable cylinders formed by arranging inclined plates in multiple stages are provided in a double form along the vertical direction, and between the cylinders there is a material filling part, The inner and outer parts are a water sprinkling part to horizontally supply water to be treated to the material filling part, and a water collection part to receive excess water, and also enable continuous movement of the material in the direction of gravity and regeneration associated with this. In a continuous filtration device, the angle formed by the horizontal plane and the line connecting the upper and lower ends of the adjacent inclined plates is arranged such that the multi-stage inclined plates constituting the cylinder corresponding to the water spraying section are used to deposit material. A continuous filtration device characterized in that the continuous filtration device is arranged so that the angle of inclination is larger than the maximum angle at which the surface is stable without collapsing when the surface is tilted. (2) Utility model registration Claim 1 is characterized in that the angle formed by the horizontal plane and the line segment connecting the upper and lower ends of the adjacent inclined plates is made larger as the lower inclined plates become closer to each other. Continuous passing device.