JPH09206774A - Carrier separation screen device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce to be affected by a descending flow of a rotary stream and to accelerate a stripping work of impurities on a screen surface of a diffusing mechanism by providing a baffle mechanism for reducing the affect by the rotary flow from the diffusing mechanism, in a carrier separation screen device of an aerobic tank for performing a biological treatment by using a carrier. SOLUTION: The aeration tank 1 is provided with the aeration mechanism 3 and an intermediate wall 4 in the inside, and the diffusion mechanism 7 at the lower part of a screen 6. An ascending flow of the rotary stream is formed with air blowing from the aeration mechanism 3, and the impurities of the screen 6 is stripped with air blowing from the diffusion mechanism 7. In this case, the baffle mechanism 9 for preventing the rotary stream from becoming a descending flow on the screen 6 surface, is provided on the upper part near the screen 6 of the intermediate wall 4 by protruding to the upper part than a water level 8. An air blowing volume is increased at the middle stage, in the opposite side of the intermediate wall 4, of the screen surface 6 and an additional diffusing mechanism 10 for more accelerating the ascending stream, is provided. Thus, clogging of the screen 6 is prevented effectively and inexpensively.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art A treatment method using an aeration tank containing 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. Therefore, there is an advantage that the processing efficiency is increased.

On the other hand, in the treatment method using the aeration tank containing the microorganism-immobilized carrier, it is necessary to prevent the outflow of the microorganism-immobilized carrier to the outside of the aeration tank. The outflow side of the aeration tank,
Alternatively, screens for carrier separation are installed on both the outflow side and the inflow side.

FIG. 3 is a schematic side sectional view of a swirl flow type deep layer aeration tank in the prior art in which a carrier separation screen is installed. A carrier 2 is placed in the aeration tank 1 and the aeration tank 1 Aeration is performed by the aeration mechanism 3 provided in the middle stage to raise the water flow, and the swirling flow indicated by the arrow 5 is generated via the inner wall 4. Further, a carrier separation screen 6 is installed on the outflow side or the outflow side and the inflow side of the treated water of 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 water surface of the treated water.

However, since the carrier separating screen 6 is apt to be clogged with contaminants, the following invention is disclosed.

In the "fluidized bed type wastewater treatment device" disclosed in Japanese Patent Laid-Open No. 3-38298, a bubble generator is installed near the screen, and the carrier is attached to the screen by the bubbles generated by the bubble generator. It is intended to prevent this.

Further, the "screen device" disclosed in Japanese Patent Laid-Open No. 6-238290 is a device for mechanically pushing out contaminants blocked on the carrier separating screen by using a brush or the like for cleaning.

[0008]

The wastewater to be treated such as sewage is inevitably contaminated with contaminants such as hair, and in order to prevent clogging of the carrier separation screen, physical blocking substances are used. Removal means is required.

In order to prevent the carrier from adhering to the screen surface and impeding the permeation of water, it is necessary to peel the carrier from the screen surface.

However, the above-mentioned Japanese Patent Laid-Open No. 3-38298.
The "fluidized bed type waste water treatment device" disclosed in Japanese Patent Laid-Open Publication No. 2003-121242 is provided with a bubble generator near the screen to prevent carriers from adhering to the screen due to bubbles generated by the bubble generator. When applied to the swirling aeration tank 1 shown in Fig. 3, the flow velocity near the screen 6 surface is sufficient for the separation of the clogging substance near the screen on the swirling upward flow side, as shown in the enlarged front view of Fig. 4. However, in the vicinity of the screen 6 surface on the downflow side of the swirl flow, the downflow speed of the swirl flow and the upflow speed of the air diffused by the air diffusing mechanism 7 below the surface of the screen 6 cancel each other. There is a problem that the flow velocity becomes slow and a sufficient flow velocity for removing foreign matters cannot be obtained.

Further, the "screen device" disclosed in Japanese Patent Laid-Open No. 6-238290 for mechanically pushing out contaminants blocked on the carrier separating screen by using a brush or the like to make the equipment expensive. In addition, there is a problem that maintenance is complicated and the carrier is likely to be destroyed.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to effectively and inexpensively prevent clogging of a carrier separating screen.

[0013]

The first means for solving the above-mentioned problems is to diffuse air in a carrier separation screen device of an aeration tank that has an aeration mechanism and an air diffusion mechanism and performs biological treatment using a carrier. A screen device for carrier separation, characterized in that a baffle mechanism for reducing the influence of the swirling flow from the aeration mechanism on the mechanism is provided on the upper part of the front surface of the screen on the inner wall.

According to the first means, the baffle mechanism prevents the downward flow of the swirling flow from occurring on the front surface of the screen on the side where the downward flow of the swirling flow is generated. Promotes peeling action.

A second means for solving the above-mentioned problems is a carrier separation screen device for an aeration tank which has an aeration mechanism and an air diffusion mechanism and performs biological treatment using a carrier. The baffle mechanism for reducing the influence of the swirling flow of the above is provided on the upper part of the front surface of the screen on the inner wall, and the screen surface is provided with an air diffusion mechanism that can adjust the air diffusion amount of each part of the screen surface. It is a screen device for carrier separation.

According to the above-mentioned second means, in addition to the action of the above-mentioned baffle mechanism, the air diffusion mechanism is an air diffusion mechanism capable of adjusting the air diffusion amount of each part of the screen surface on the screen surface. The peeling action of the object is further promoted, and a flow rate for uniform peeling is formed over the entire surface of the screen.

A third means for solving the above-mentioned problems is that a diffusing mechanism for each part of the screen surface is provided in a plurality of stages in the height direction, and the carrier separating screen according to claim 2 It is a device.

According to the above-mentioned third means, by providing a plurality of diffusing mechanisms on the screen surface, it is possible to prevent the bubble curling phenomenon of the diffusing mechanism, and to provide a uniform flow velocity for peeling over the entire screen. Form.

A fourth means for solving the above-mentioned problems is that the diffusing mechanism for each part of the screen surface is composed of a tube having ejection holes with a large ejection capacity. Screen device for carrier separation.

According to the above-mentioned fourth means, the influence of the downward flow of the swirling flow is reduced by increasing the diffused jet amount, and a uniform flow velocity for separation is formed over the entire screen.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view schematically showing a carrier separating screen device of the present invention, in which an aeration mechanism 3 is provided in an aeration tank 1.
And an inner wall 4 is provided.

Reference numeral 6 denotes a screen, and an air diffuser 7 is provided below the screen 6, and an upward flow of a swirl flow is formed by the air blown from the aeration mechanism 3, and the air blown by the air diffuser 7 The contaminants on the screen 6 are removed.

Reference numeral 9 is a baffle mechanism provided on the upper portion of the inner wall 4 near the screen 6, and the swirling flow is generated by the screen 6
In order to prevent downward flow on the surface, it is provided so as to project above the water surface 8.

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

FIG. 2 is a front cross-sectional view of the screen 6, and 9 is a baffle mechanism provided on the inner wall 4, in which the swirling flow becomes a downward flow on the screen 6 surface. In addition, the swirling flow downward flow side (left side in the drawing) of the air diffusing mechanism provided below the front surface of the screen 6 is provided with the air diffusing mechanism 10 having a large blowout port to increase the upward flow. As a result, the impurities on the screen 6 are removed.

Although the present invention has the above-mentioned structure, the baffle mechanism 9 has a curved shape, a semi-cylindrical shape, as well as a plate shape.
The shape may be angular or irregular, and the point is that the flow on the surface of the screen 6 does not have to be a downward flow. Also,
The baffle mechanism 9 may be made of concrete, metal, or plastic.

Further, the height of the baffle mechanism 9 is equal to that of the water surface 8.
Or a value protruding from the water surface 8, which is about 1/100 to 1/5, preferably about 1/20 to 1/10, of the length of the aeration tank 1. Further, the value from the front surface 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 air diffusion strength on the surface of the screen 6, it is desirable to install independent air diffusion mechanisms on the downward flow side and the upward flow side of the swirling flow so that a uniform flow velocity can be obtained over the entire surface of the screen 6. . As for the installation position of the air diffusing mechanism, as shown in FIG.
Alternatively, when the diffused bubbles rise up as they rise, as shown in FIG. 1, several steps may be provided for each height, and the screen 6 may be provided not only on the front side but also on the rear side. Good.

The aeration method may be a tube having a plurality of holes or a diffuser or the like.

[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 action of separating the impurities on the screen surface of the diffusing mechanism on the downward flow side is promoted.

Further, since impurities are not mechanically removed,
Does not damage the screen or carrier.

Further, since the baffle mechanism and the air diffusing mechanism capable of adjusting the air diffusing can give a uniform flow velocity to the entire surface of the screen, it is possible to prevent the screen from clogging stably over the entire surface of the screen. .

[Brief description of 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 cross-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 diffuser 8 Water surface 9 Baffle mechanism 10 Air diffuser (present invention) 11 Air diffuser (present invention)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masato Fujino, 1-2 Marunouchi, Chiyoda-ku, Tokyo Nihon Kokan Co., Ltd. (72) Seiichi Kanamori 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nippon Steel Tube Co., Ltd.

Claims (4)

[Claims] 1. A screen device for separating a carrier of an aeration tank, which has an aeration mechanism and an aeration mechanism and performs biological treatment using a carrier, for reducing the influence of a swirling flow from the aeration mechanism on the aeration mechanism. A screen device for separating carriers, characterized in that a baffle mechanism is provided on an upper part of the front surface of the screen on the inner wall. 2. A carrier separation screen device for an aeration tank, which has an aeration mechanism and an aeration mechanism and performs biological treatment using a carrier, for reducing the influence of a swirling flow from the aeration mechanism on the aeration mechanism. A carrier separation screen device, wherein a baffle mechanism is provided on an upper part of the front surface of the screen on the inner wall, and further an air diffusion mechanism capable of adjusting an air diffusion amount of each part of the screen surface is provided on the screen surface. 3. The carrier separating screen device according to claim 2, wherein a plurality of diffusing mechanisms for each part of the screen surface are provided in the height direction. 4. The carrier separating screen device according to claim 2, wherein the air diffusing mechanism to each part of the screen surface is composed of a tube having an ejection hole having a large ejection capacity.