JP4284586B2 - Carrier separation device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a carrier separation apparatus, and more particularly to a carrier separation apparatus employed in a carrier addition type wastewater treatment apparatus.
[0002]
[Prior art]
In the wastewater treatment apparatus of the carrier addition method, the wastewater is biologically treated by bringing the carrier on which microorganisms are immobilized in a treatment tank into contact with the wastewater. In this wastewater treatment apparatus, as shown in FIG. 4, a screen 3 is disposed in the vicinity of the discharge port 2 of the treatment tank 1, and the screen 3 prevents the carrier from flowing out of the treatment tank. (See Patent Document 1).
[0003]
[Patent Document 1]
JP-A-9-117785
[Problems to be solved by the invention]
By the way, the screen 3 is configured by stretching a plurality of wires 3a in parallel, and the wires 3a are disposed so as to be inclined. And the wire 3a is mutually connected by the stay 4 in multiple places, in order to ensure a space | interval and intensity | strength.
[0005]
Therefore, fibrous materials such as human hair are easily entangled with the stay 4 on the screen 3, which may cause clogging. For this reason, the operator must periodically clean the screen.
[0006]
The present invention has been made in view of such circumstances, and provides a carrier separation device that can reduce the frequency of cleaning of workers by using a screen that is less likely to be entangled with fibrous materials such as human hair. With the goal.
[0007]
[Means for Solving the Problems]
The carrier separation device according to claim 1 of the present invention is provided in a wastewater treatment device for biologically treating the wastewater by bringing the carrier on which microorganisms are immobilized in a treatment tank into contact with wastewater, A screen configured by extending wires in parallel is arranged near the discharge port of the processing tank so that the wires are inclined with respect to the vertical line, and the carrier flows out of the processing tank by the screen. In the apparatus for separating the carrier, the base end is passed to each wire at a plurality of positions in the height direction of the wire, and the trough is arranged with the tip positioned on the discharge port side of the treatment tank. while setting the respective eave, with its tip is placed to be inclined so as to face downward, respectively is arranged so as to cover the proximal end of the overhang eaves positioned above is positioned below, each Characterized by being arranged air jet pipe immediately below the bottom of the eaves of the.
[0008]
According to the carrier separating apparatus of the present invention, the wires are firmly supported by the wrinkles, and the distance between them is reliably maintained, and since it is not a rod like the conventional stay, the fibrous material such as human hair is There is no risk of getting tangled.
[0009]
Further, in the carrier separating apparatus according to claim 1 of the present invention, each of the scissors is installed so as to be inclined so that the tip thereof is directed downward, and the scissor located above is disposed on the base of the scissors located below. It is characterized by being arranged so as to cover the ends.
[0010]
According to the carrier separating apparatus of the present invention, clean air repeatedly flows from the back surface to the front surface of the screen along the ridges, so that the entire surface of the screen can be washed.
[0011]
The carrier separating apparatus according to claim 1 of the present invention is characterized in that an air ejection pipe is disposed immediately below the lowermost ridge.
[0012]
According to the carrier separating apparatus of the present invention, the bubbles formed by the air ejected from the air jet pipe are reliably captured by the lowermost ridge, and they are sequentially raised along the screen using the upper ridge as a guide. Therefore, the water flow on the screen surface is not obstructed.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of a carrier separation device according to the present invention will be described in detail with reference to the accompanying drawings.
[0014]
FIG. 1 is a block diagram conceptually showing a nitrification apparatus as an example of a wastewater treatment apparatus to which the carrier separation apparatus of the present invention is applied, FIG. 2 shows the structure of the screen, and FIG. 3 shows the screen. It shows the cleaning action.
[0015]
The nitrification apparatus 10 is mainly provided with a nitrification tank 11 into which waste water such as sewage containing organic matter and ammonia nitrogen components flows, and at the bottom of the nitrification tank 11, and for microorganisms carried on a large number of carriers 12. An aeration apparatus 13 for supplying air, an inflow pipe 14 for wastewater, and a screen 16 provided in the vicinity of a discharge port 15 for the treated water treated in the nitrification tank 11 and a surface of the screen 16 for separating the carrier from the treated water. The carrier separation device 30 is provided with an air ejection pipe 17 that generates air bubbles along the carrier.
[0016]
The aeration apparatus 13 includes a plurality of diffuser plates 18 disposed so as to cover the entire area near the bottom of the nitrification tank 11, and a blower 20 that supplies compressed air to the diffuser plates 18 via an air pipe 19. It is configured.
[0017]
The screen 16 is provided to be inclined toward the bottom side of the nitrification tank 11, and defines the nitrification tank 11 into a tank main part 11 a for accommodating the carrier 12 and a trough part 11 b having a discharge port 15. In this screen 16, a large number of wedge wires 22 are arranged in a vertical direction on a rectangular support frame 21 with an interval (about 1.5 mm) through which the carrier 12 does not pass. And between those wires 22, as shown in FIG. 2 and FIG. 3, a rib (plate) 23 is provided to maintain and reinforce the distance between the wires 22. The flanges 23 are arranged at appropriate intervals over the entire length of the wire 22, and a flange 23 a bent downward is formed on the other side except the side on the wire 22 side.
[0018]
The air ejection pipe 17 is disposed on the trough portion 11b side of the screen 16 immediately below the lowermost flange 23, and extends over almost the entire width of the flange 23. And it has the some air jet 17a in the appropriate position.
[0019]
At the upper end of the screen 16, a rectangular upper plate 24 is provided along the width direction of the screen 16, so that the treated water treated in the tank main part 11 a of the nitrification tank 11 is not discharged beyond the screen 16. ing. A support frame 21 is fixed to a horizontal support plate 25 on the side wall of the nitrification tank 11 at the lower end of the screen 16. As a result, part of the treated water and activated sludge treated in the tank main part 11a of the nitrification tank 11 passes through the screen 16 and flows out to the trough part 11b, while the carrier 12 introduced into the nitrification tank 11 is screened. 16 prevents outflow to the trough portion 11b.
[0020]
Further, in the nitrification apparatus 10, a guide plate 26 is provided on the surface side (tank main portion 11 a side) of the screen 16 in the nitrification tank 11 in parallel to the surface of the screen 16, and between the screen 16 and the guide plate 26. A flow path 27 is formed in the channel. The upper end portion of the guide plate 26 is bent obliquely upward, and the upper opening of the flow path 27 has a trumpet shape and is formed near the liquid surface.
[0021]
In addition, a foam collecting plate 28 that forms a cross-sectional shape with the upper plate 24 is provided in the tank main part 11 a of the nitrification tank 11. Thereby, it becomes easy to collect the bubbles by the air aerated from the diffuser plate 18 into the tank main portion 11 a between the upper plate 24 and the foam collecting plate 28.
[0022]
Next, the operation of the nitrification apparatus 10 to which the carrier separation apparatus 30 of the present invention is applied will be described.
[0023]
Waste water such as sewage flows into the tank main part 11 a of the nitrification tank 11 from the inflow pipe 14. In the tank main part 11a, the support | carrier 12 which carry | supported activated sludge and nitrifying bacteria, and wastewater are contacted in the aerobic state with the aeration air from the diffuser board 18. FIG.
[0024]
Thereby, nitrification treatment of waste water is performed. The treated water that has been nitrified in the tank main section 11a passes through the screen 16 and is discharged to the trough section 11b, and is sent from the discharge port 15 to the next step.
[0025]
On the other hand, air bubbles aerated from the diffuser plate 18 into the nitrification tank 11 gather between the upper plate 24 and the foam collecting plate 28, and the liquid between the upper plate 24 and the foam collecting plate 28 is caused by the air lift action by the air. The surface rises from the other liquid level in the tank main part 11a. The rising liquid level flows into the flow path 27 from the upper opening of the flow path 27, and forms a water flow that descends in the flow path 27 and flows out from the lower opening. In this way, by generating a water flow parallel to the surface of the screen 16, it becomes difficult for fibrous materials such as human hair in the wastewater to adhere to the wire 22 of the screen 16. Moreover, since the deposit | attachment adhering to the wire 22 of the screen 16 is scraped off by a water flow, the screen 16 is wash | cleaned.
[0026]
In this case, the flow rate of the water flow for cleaning the screen 16 is at least five times the flow rate at which treated water in the tank main part 11a of the nitrification tank 11 passes through the screen 16 and flows out to the trough part 11b. If so, the clogging of the screen 16 can be more effectively prevented. In order to obtain a water flow that meets the set conditions, it is preferable that the liquid level between the upper plate 24 and the foam collecting plate 28 be higher than the other liquid level by 5 cm or more by the air lift action.
[0027]
Further, the bubble 17b formed by the air ejected from the ejection port 17a of the air ejection pipe 17 rises and is captured by the lowermost flange 23. Then, the bubbles 17b rise along the ridges 23 and exit to the front surface side (tank main portion 11a side) of the screen 16, as shown in FIG. 3, and then pass through the screen 16 again to the back side (trough portion 11b side). Return to. The bubble hits the upper ridge 23 and rises along the ridge 23.
[0028]
That is, as shown in FIG. 3, the bubbles 17 b formed by the air ejected from the air ejection pipe 17 rises following the screen 16 and cleans fibrous materials such as human hair entangled with the screen 16. .
[0029]
Moreover, since the role of the stay which maintains the space | interval of the wire 22 and hold | maintains them in the tank 11 is performed with the collar 23, ie, a plate, there is no possibility that fibrous materials, such as human hair, may get entangled.
[0030]
Note that the protrusion amount (horizontal length), inclination (angle with respect to the horizontal), etc. of the ridge 23 reliably captures the rising bubbles 17b in consideration of the distance between the upper and lower ridges 23, 23, It is preferable to set the bubbles 17b appropriately so that the bubbles 17b can be quickly guided to the screen 16 side. For example, when the distance between the ridges 23 and 23 is small, if the inclination of the ridge 23 is too large and the distance between the ridges 23 is too large, the flow of waste liquid from the tank main part 11a to the trough part 11b may be hindered. .
[0031]
In this embodiment, the example in which the carrier separation device 30 is applied to the nitrification device 10 as a wastewater treatment device has been described. However, the present invention is not limited to this, and the carrier on which microorganisms are immobilized flows out of the treatment tank. Applies to all wastewater treatment equipment with a screen to prevent it.
[0032]
【The invention's effect】
As described above, according to the carrier separating apparatus of the first aspect of the present invention, the distance between the wires is reliably maintained by the scissors, the strength of the screen is increased, and the rod-like shape as in the conventional stay is provided. Therefore, there is no possibility of entanglement of fibrous materials such as human hair, the number of screen cleanings by workers can be reduced, and the operating cost can be reduced.
[0033]
Further, in the carrier separating apparatus according to claim 2 according to the present invention, in claim 1, each of the scissors is installed so as to be inclined so that the tip thereof is directed downward, and the scissors positioned above are disposed below it. They are arranged so as to cover the base ends of the ridges located.
[0034]
Therefore, the clean air repeatedly flows from the back surface of the screen to the front surface along the ridge and rises along the screen, so that the entire surface of the screen can be cleaned.
[0035]
Moreover, in the carrier separation device according to claim 3 of the present invention, in claim 1 or 2, an air ejection pipe is disposed immediately below the lowermost ridge.
[0036]
Therefore, the bubbles formed by the air ejected from the air injection pipe are reliably captured by the lowermost ridge, and they are sequentially raised along the screen using the upper ridge as a guide. There is no hindrance and the screen cleaning effect of the water flow is not disturbed.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an embodiment in which a wastewater treatment apparatus to which a carrier separation apparatus according to the present invention is applied is a nitrification apparatus.
FIG. 2 is an enlarged cross-sectional view showing in detail the carrier separating apparatus shown in FIG. 1;
FIG. 3 is an operation diagram for explaining the operation of the carrier separation device shown in FIG. 2;
FIG. 4 is a perspective view conceptually showing a conventional carrier separating apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Nitrification apparatus, 11 ... Nitrification tank, 11a ... Tank main part, 11b ... Trough part, 12 ... Carrier, 13 ... Aeration apparatus, 14 ... Inflow pipe, 15 ... Discharge port, 16 ... Screen, 17 ... Air ejection pipe, 17a ... Air jet port, 17b ... Bubble, 18 ... Air diffuser, 19 ... Air piping, 20 ... Blower, 21 ... Support frame, 22 ... Wedge wire, 23 ... Bridge (plate), 23a ... Flange, 24 ... Upper plate , 25 ... support plate, 26 ... guide plate, 27 ... flow path, 28 ... foam collecting plate, 30 ... carrier separation device

Claims (1)

A screen that is provided in a wastewater treatment apparatus that biologically treats the wastewater by bringing the carrier on which microorganisms are immobilized in the treatment tank into contact with the wastewater, and is configured by stretching a plurality of wires in parallel. In the apparatus for separating a carrier, the wire is disposed near the discharge port of the treatment tank so as to be inclined with respect to a vertical line, and the carrier is prevented from flowing out of the treatment tank by the screen.
While placing the base end in each of the plurality of locations in the height direction of the wire, and placing the tip on the discharge port side of the treatment tank, respectively, and arranging the ridges ,
The scissors are installed so that their tips are inclined downwards, and the scissors located above cover the base end of the scissors located below, respectively. An apparatus for separating a carrier, characterized in that an air ejection pipe is disposed immediately below a lower ridge .

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