JP3301299B2 - Screen device for carrier separation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to organic matter in wastewater,
The present invention relates to a screen device for separating a microorganism-immobilized carrier used for biologically purifying an inorganic substance, and more particularly to a screen device for separating a carrier when the carrier is charged into a swirling type aeration tank including deep aeration. .

[0002]

2. Description of the Related Art A treatment method using an aeration tank charged with a microorganism-immobilized carrier can maintain a high concentration of microorganisms and a high concentration of useful microorganisms such as nitrifying bacteria as compared with the standard activated sludge method. This has the advantage that the processing efficiency can be increased.

[0003] On the other hand, in the treatment method using an aeration tank into which the microorganism-immobilized carrier is charged, it is necessary to prevent the microorganism-immobilized carrier from flowing out of the aeration tank. Outflow side of the aeration tank into which
Alternatively, screens for carrier separation are installed on both the outflow side and the inflow side.

FIG. 3 is a schematic cross-sectional side view of a conventional aeration flow type deep aeration tank in which a carrier separating screen is installed. In the aeration tank 1, a carrier 2 is charged. Aeration is performed by the aeration mechanism 3 provided in the middle stage to raise the water flow, and a swirling flow indicated by an arrow 5 is generated through the middle wall 4. In addition, a carrier separation screen 6 is provided on the outflow side or the outflow side and the inflow side of the treated water in the aeration tank 1, and an air diffusion mechanism 7 is provided below the carrier separation screen 6.
Is provided. In addition, 8 is the surface of the treated water.

However, the following invention is disclosed since the carrier separation screen 6 is liable to be clogged by contaminants.

In the "fluidized bed wastewater treatment apparatus" disclosed in Japanese Patent Application Laid-Open No. 3-38298, a bubble generator is installed near a screen, and a carrier adheres to the screen by bubbles generated by the bubble generator. Is to prevent this.

The "screen device" disclosed in Japanese Patent Application Laid-Open No. Hei 6-238290 is a device for mechanically extruding contaminants clogged in a carrier separating screen by using a brush or the like to clean the material.

[0008]

The wastewater to be treated, such as sewage, is inevitably contaminated with impurities such as hair, and in order to prevent the carrier separation screen from being clogged, it is necessary to physically remove the clogging substance. Removal means is required.

Further, it is necessary to peel the carrier from the screen surface in order to prevent the carrier from adhering to the screen surface and hindering the permeation of water.

However, Japanese Patent Laid-Open Publication No.
JP-A No. 2000-205, a "fluidized bed wastewater treatment apparatus" which installs a bubble generator near the screen and prevents the carrier from adhering to the screen due to bubbles generated by the bubble generator, When applied to the aeration tank 1 of the swirling flow type shown in FIG. 3, the flow velocity near the screen 6 surface is sufficient for peeling off the blocking substance as shown in the enlarged front view of FIG. In the vicinity of the screen 6 on the downward flow side of the swirl flow, the downward flow velocity of the swirl flow and the upward flow velocity of air diffused by the diffusion mechanism 7 below the screen 6 cancel each other. There is a problem that the flow velocity becomes slow and a sufficient flow velocity for peeling off impurities cannot be obtained.

Further, the "screen device" disclosed in Japanese Patent Application Laid-Open No. Hei 6-238290, which mechanically extrudes and cleans foreign substances clogged in the carrier separating screen by using a brush or the like, requires high equipment cost. At the same time, there is a problem that the maintenance is complicated and the carrier is likely to be destroyed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and has as its object to effectively and inexpensively prevent a blockage of a carrier separating screen.

[0013]

A first means for solving the above-mentioned problems is to provide a screen separation device for a carrier in an aeration tank having an aeration mechanism and a diffusion mechanism and performing biological treatment using a carrier. A carrier separation screen device characterized in that a baffle mechanism for reducing the effect of a swirling flow from an aeration mechanism on the mechanism is provided above a front surface of a screen on an intermediate wall.

According to the first means described above, since the downward flow of the swirling flow does not occur on the front surface of the screen where the downward flow of the swirling flow occurs due to the baffle mechanism, the screen contaminants by the air diffusing mechanism are removed. Promotes peeling action.

A second means for solving the above-mentioned problem is to provide a screen device for separating a carrier in an aeration tank which has an aeration mechanism and an aeration mechanism and performs biological treatment using a carrier. The baffle mechanism to reduce the influence of the swirling flow is provided at the upper part of the front surface of the screen on the middle wall, and further, the air diffusion mechanism is provided on the screen surface so that the air diffusion amount of each part of the screen surface can be adjusted Is a screen device for separating carriers.

According to the above-mentioned second means, in addition to the operation of the baffle mechanism, the air diffusion mechanism is an air diffusion mechanism capable of adjusting the amount of air diffusion at each portion of the screen surface, so that the screen contamination is reduced. It further promotes the peeling action of the object and forms a flow rate for uniform peeling over the entire screen.

According to a third means for solving the above-mentioned problem, a screen for separating carriers according to claim 2, wherein a plurality of air diffusing mechanisms for each portion of the screen surface are provided in the height direction. Device.

According to the third means, the air diffusion mechanism is provided in a plurality of stages on the screen surface, so that the air bubble winding phenomenon of the air diffusion mechanism can be prevented, and the flow rate for uniform peeling over the entire screen is reduced. Form.

According to a fourth means for solving the above-mentioned problem, a mechanism for diffusing air to each part of the screen surface is constituted by a tube having an ejection hole having a large ejection capacity. Screen device for carrier separation.

According to the fourth means described above, the influence of the downward flow of the swirling flow is reduced by increasing the amount of diffused air, and a uniform flow velocity is formed over the entire screen.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view schematically showing a screen device for separating carriers according to the present invention, wherein an aeration mechanism 3 is provided in an aeration tank 1.
And an intermediate wall 4.

Reference numeral 6 denotes a screen, and an air diffusion mechanism 7 is provided below the screen 6. An upward flow of the swirling flow is formed by blowing air from the aeration mechanism 3, and the air is blown from the air diffusion mechanism 7. The impurities on the screen 6 are peeled off.

Reference numeral 9 denotes a baffle mechanism provided above the middle wall 4 near the screen 6.
In order to prevent a downward flow on the surface, it is provided so as to protrude above the water surface 8.

Further, in the middle stage on the opposite side of the middle wall 4 of the screen 6, in addition to the conventional air diffusing mechanism 7, in addition to the conventional air diffusing mechanism 7, in order to increase the air blowing capacity to the screen 6 and further promote the upward flow. An additional air diffusing mechanism 10 is provided.

FIG. 2 is a front sectional view of the screen 6. 9 is a baffle mechanism provided on the middle wall 4. The baffle mechanism 9 turns the swirling flow downward on the screen 6. Further, among the air diffusion mechanisms provided below the front surface of the screen 6, the air diffusion mechanism 10 having a large outlet is installed on the downward flow side (left side in the drawing) of the swirling flow to increase the upward flow. Is to peel off foreign substances on the screen 6 surface.

Although the present invention has the above-described configuration, the shape of the baffle mechanism 9 is not limited to a plate shape, but a curved shape, a semi-cylindrical shape,
The shape may be any of a square shape and an irregular shape. In short, the flow on the surface of the screen 6 is not required to cause a downward flow. Also,
The material of the baffle mechanism 9 may be any of concrete, metal, and plastic.

Further, the height of the baffle mechanism 9 is
Or about 1/100 to 1/5 with respect to the length of the aeration tank 1, preferably about 1/20 to 1/10. The value from the front of the screen 6 to the inside of the aeration tank 1 is preferably a value that does not hinder the swirling flow of the aeration tank 1.

As for the intensity of air diffusing on the screen 6, it is desirable to install independent air diffusing mechanisms on the downward flow side and the upward flow side of the swirling flow so as to obtain a uniform flow velocity over the entire surface of the screen 6. . As shown in FIG. 2, the installation position of the air diffusing mechanism is to increase the ejection amount at the bottom of the screen 6,
Alternatively, in the case where the air bubbles rise as the diffused air bubbles rise, several stages may be provided for each height as shown in FIG. 1 or provided not only on the front surface of the screen 6 but also on the rear surface. Good.

The air diffusion method may be a method in which a plurality of holes are formed in a tube, or a shape such as a diffuser.

[0031]

As described above, according to the present invention, the effect of the downward flow of the swirling flow is reduced by the baffle mechanism, so that the function of separating the foreign matter on the screen surface of the air diffusion mechanism on the downward flow side is promoted.

Also, since no foreign matter is mechanically removed,
No damage to screen and carrier.

Further, a uniform flow velocity can be given to the entire screen by the baffle mechanism and the air diffusion mechanism capable of adjusting the air diffusion, so that the screen clogging can be stably prevented over the entire screen. .

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of the present invention.

FIG. 2 is a schematic front sectional view of the present invention.

FIG. 3 is a front sectional view of a conventional aeration tank.

FIG. 4 is an enlarged front sectional view of a conventional aeration tank.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aeration tank 2 Carrier 3 Aeration mechanism 4 Middle wall 5 Swirling upward flow 6 Screen 7 Air diffusion mechanism 8 Water surface 9 Baffle mechanism 10 Air diffusion mechanism (the present invention) 11 Air diffusion mechanism (the present invention)

──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Masato Fujino 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (72) Inventor Seiichi Kanamori 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Japan (56) References JP-A-7-284793 (JP, A) JP-A-8-24896 (JP, A) JP-A 63-63196 (JP, U) (58) Fields investigated (Int) .Cl. ⁷ , DB name) C02F 3/08 ZAB B01D 39/12

Claims (4)

(57) [Claims] In a screen device for separating a carrier in an aeration tank which has aeration mechanism and a diffusion mechanism and performs biological treatment using a carrier, the effect of a swirling flow from the aeration mechanism on the diffusion mechanism is reduced. A screen device for separating carriers, wherein a baffle mechanism is provided above a front surface of a screen on a middle wall. 2. A screen device for separating a carrier in an aeration tank which has aeration mechanism and a diffusion mechanism and performs biological treatment using a carrier, for reducing an influence of a swirling flow from the aeration mechanism on the diffusion mechanism. A screen device for separating a carrier, comprising: a baffle mechanism provided on an upper portion of a front surface of a screen on an intermediate wall; and a diffusing mechanism capable of adjusting a diffusing amount of each part of the screen surface on the screen surface. 3. The screen device for separating carriers according to claim 2, wherein a plurality of air diffusing mechanisms are provided in the height direction in each part of the screen surface. 4. The screen device for separating carriers according to claim 2, wherein the mechanism for diffusing air to each part of the screen surface comprises a tube having an ejection hole having a large ejection volume.