JP3521069B2 - Carrier separation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] TECHNICAL FIELD The present invention relates to a carrier separation device.
In particular, contact between wastewater and microbial carriers under aerobic conditions
The wastewater into a biological treatment tank.
Transfer means for transferring the microorganism carrier, and treating the microorganism carrier.
The present invention relates to a carrier separation device equipped with a separation means for separating water from water.
You. [0002] 2. Description of the Related Art The process of a modified activated sludge circulation method is shown in FIG.
As shown, the denitrification tank 1, the nitrification tank 2, and the solid-liquid separation tank 3
The liquid level of each tank is the same as that of denitrification tank 1, nitrification tank 2, and solid-liquid separation tank 3.
It is configured so that the liquid level becomes lower in order, and flows into each tank sequentially
Configured. And the wastewater flowing into the denitrification tank 1
Is mixed with the activated sludge and sent to the nitrification tank 2 where the nitrification tank 2
Ammonia nitrogen in wastewater in aerobic conditions
Is processed. Nitrification liquid nitrified in the nitrification tank 2 circulates
Circulated through the pipe 4 to the denitrification tank 1,
The nitrification liquid is denitrified under anaerobic conditions. This allows
Ammoniacal nitrogen in wastewater is removed as nitrogen gas
You. The liquid circulation between the nitrification tank 2 and the denitrification tank 1
A part of the liquid from the nitrification tank 2 as treated water
And the activated sludge is settled and separated in the solid-liquid separation tank 3.
Release the supernatant. [0003] By the way, for nitrification in the nitrification tank 2,
Nitrifying bacteria, which are microorganisms, are used for denitrification treatment in the denitrification tank 1.
Because the growth ability is smaller than the denitrifying bacteria that are microorganisms,
Nitrification performance decreases in winter or the like when the water temperature decreases.
As a countermeasure for this, in recent years, carriers supporting nitrifying bacteria at high concentration
Into the nitrification tank 2 to improve the nitrification performance.
Has been done. In addition, waste that flows into the nitrification tank 2 from the denitrification tank 1
Water flows into the upstream position of the nitrification tank 2 and flows out from the downstream position
I do. Therefore, when the carrier is used, the nitric acid in the nitrification tank 2
In order to maintain good gasification performance,
To prevent the carrier from shifting to the downstream side.
Must be prevented from flowing out of the nitrification tank 2
You. For this reason, the carrier is placed in the nitrification tank 2 at an upstream position in the nitrification tank 2.
The transfer means and the carrier for transferring to the
Separation means are provided to prevent outflow of the body. FIG. 5 shows a conventional transfer means in a nitrification tank 2.
Wastewater treatment apparatus 5 provided with a carrier separation device comprising separation means
FIG. As shown in FIG. 5, the transfer means 6 comprises a nitrification tank.
A carrier transfer pump 6A is provided at the bottom on the downstream side of 2 to transfer the carrier.
The mixed solution of the carrier and the treated water sucked by the pump 6A is supplied to the pipe 6
It was to be transported upstream through B. Also a minute
The separating means 7 is provided at the overflow port of the trough 7B where the treated water overflows.
By installing Clean 7A, the carrier can be separated from the treated water.
Was separated. In addition, overflow water from trough 7B is supplied to pit 8
Collected by the circulating pump 8A provided in the pit 8
Part of the running water is circulated to the denitrification tank 1 through the circulation pipe 4.
Was. The remaining overflow water collected in the pit 8 is settled.
Spills into Seki Pond. [0006] SUMMARY OF THE INVENTION However, the conventional
The carrier separation device including the transfer means and the separation means is provided with a transfer mechanism.
Because the stage 6 and the separating means 7 are independent as separate devices
However, there is a disadvantage that the installation space is large. Also, since the device is independent, the carrier
Transfer pump 6A for transfer and a part of treated water
Running circulation pump 8A
There is a disadvantage that the strike becomes high. [0008] Further, the conventional separation means 7 is such that the treated water overflows.
Screen 7A at the overflow of the trough 7B
By using the flow of the treated water overflowing to the trough 7B
The carrier is separated by the screen 7A.
Has the drawback that there is a limit in increasing
You. That is, even if the depth direction of the screen 7A is increased,
Since the effective area of Lean 7A is almost the same,
The amount of liquid flowing over the nozzle 7B hardly changes. Also,
The rough 7 </ b> B and the screen 7 </ b> A are located at the downstream position of the nitrification tank 2.
If provided along the side wall of the nitrification tank 2,
It is only possible to increase the discharge of treated water. Only
However, in this case, an upstream position of the nitrification tank 2 into which the wastewater flows.
Flows into the nitrification tank 2 because the position of the trough 7B approaches
Danger of wastewater overflowing into the trough 7B without treatment
Is not a fundamental countermeasure.
And the trough 7B and the screen 7A are provided along the side wall.
The equipment cost for this increases. The present invention has been made in view of such circumstances.
The carrier transfer means and the separation means are integrated
Impact and also remove some of the treated water.
Since the driving force circulating in the nitrification tank is also used, equipment costs are reduced.
And running costs can be reduced, and the amount of treated water discharged
Can be easily handled even when the amount of
It is an object to provide a separation device. [0010] The present invention achieves the above object.
Wastewater into biological treatment tanks.
Transfer means for transferring the introduced microorganism carrier in the treatment tank; and
And the microorganism carrier from the treated water discharged from the treatment tank.
In a carrier separation device provided with separation means for separating,
It is arranged vertically in the processing tank and has an inlet at the lower end.
A cylindrical body having an outlet at the endThe inner cylinder and outer cylinder with double cylinder
And a structure between the inner cylinder and the inner cylinder and the outer cylinder.
One of them is a carrier feed channel and the other is a treated water channel.
From two channelsThe formed tubular structure and the two streams
A carrier feed passage provided in the carrier feed passage in the passage;
By aerating air into the flow path and using the air lift effect of air,
An upward flow is generated in the carrier feed channel and the flow channel
Aeration means for increasing the liquid level inside the processing tank to be higher than the liquid level inside the processing tank
And provided at the lower end of the tubular structure, inside the tubular structure
Of the mixture of the treated water and the microorganism carrier flowing into
That is, from the mixed liquid that is going to flow into the treated water flow path side,
A screen that separates the microbial carrier and passes only the treated water
And a carrier outlet channel side, and the
The mixed solution that has flowed into the carrier feed channel is
Transfer channel to transfer to desired position in treatment tank by action
And an outlet of the treated water flow path, wherein the treated water flow
The treated water that has flowed into the channel is subjected to a difference in water level before and after the treatment tank.
Forming an upward flow in the treated water flow path by the pushing force
A discharge channel for discharging outside the processing tank, wherein the transfer means
And the separating means are combined. According to the present invention, the processing is performed by flowing into the processing tank.
The mixed liquid of the treated water and the carrier flows at the lower end of the cylindrical structure.
It flows in from the entrance. Of the inflowing mixture, the treated water flow path
The mixture flowing to the side is microbial-borne by the screen.
The body is separated and only the treated water passes. Meanwhile, carrier feed
Mixed liquid flowing on the roadside and microbes separated by the screen
The material carrier is transported by the air lift,
Return to a desired position in the treatment tank,
Is done. Thereby, the microorganism carrier is transferred in the treatment tank.
At the same time, microbial carriers are separated from the treated water discharged from the treatment tank.
Can be separated. Further, the carrier feed passage passing through the screen is provided.
Water flowing from the side to the treated water flow path side
Along with the water,
Can be washed. Furthermore, this treated water rises
Removes carriers that are clogged on the screen.
Can be. In the present invention, the carrier transferring means and the carrier are separated.
Since the structure is integrated with the separation means, the transfer of the carrier and
The apparatus for separation can be made compact. This
As a result, installation space can be reduced and equipment cost can be reduced.
The strike can be reduced. Further, the present invention relates to a screen having a cylindrical structure.
Liquid mixture that is provided at the lower end of the
With a structure that separates the microorganism carrier from the
In the treated water that has flowed into the treated water flow path,
The water in the treated water flow path
It is discharged outside the device. In this case, aerated water is also used in the treated water flow path.
A step is provided and the air lift of the step causes the liquid level of the treated water flow path.
Is higher than the liquid level in the denitrification tank
For example, it is not only necessary to discharge treated water outside the equipment,
Part of the treated water can be returned to the denitrification tank via a pipe.
Therefore, a pump for circulating part of the treated water to the denitrification tank
Is no longer necessary. In addition, the upward flow generated in the treated water flow path
The treated water flows into the treated water flow path through the entire screen.
The screen area is smaller than before.
Also increases the amount of treated water passing through the screen.
In addition, the entire screen can contribute to carrier separation.
Wear. [0016] BRIEF DESCRIPTION OF THE DRAWINGS FIG.
A preferred embodiment of the body separating device will be described in detail. FIG. 1 shows a carrier separation device 16 of the present invention.
For explaining the first embodiment of the wastewater treatment apparatus 10
It is a front view, and untreated waste from the denitrification tank (see FIG. 4) in the previous stage.
The water flows into the wastewater treatment device 10 and the treated water is
An example will be described in which the liquid flows into a solid-liquid separation tank (see FIG. 4) at a later stage.
You. In the first embodiment, the wastewater treatment device 10
Of a deep tank type nitrification tank with a depth of about 10m
An example will be described. As shown in FIG. 1, the wastewater treatment apparatus 10 comprises:
Mainly, many microbial carriers 14, 1 carrying nitrifying bacteria
4... (Hereinafter referred to as “carrier”)
And the carrier flowing from the upstream side to the downstream side in the nitrification tank 12
Transfer means for transferring 14 to the upstream position A and the nitrification tank 12
Separation means for separating the carrier 14 from the treated water discharged from
And a carrier separation device 16 which is integrated into an integrated structure.
You. The nitrification tank 12 is located at a position A upstream from the denitrification tank to the nitrification tank 12.
Wastewater flowing into the tank and the carrier 14 and the
And activated sludge (not shown) under aerobic conditions
Wastewater is biologically treated, and the treated water is nitrified.
Part of the treated water is circulated from the downstream position B of the tank 12 to the denitrification tank
And the remainder is discharged to a solid-liquid separation tank. As nitrification tank 12
Is a deep tank type nitrification tank, and the downstream of the nitrification tank 12 is used.
At position B, a carrier separation device 16 is provided. Incidentally, in FIG.
Represents the nitrification tank 1 because of the large size of the carrier separation device 16.
2, the distance between the upstream position A and the downstream position B is drawn short.
But they are actually farther apart. The carrier separation device 16 mainly includes the nitrification tank 1
2, a tubular structure 18 provided in a vertical direction, and a tubular structure
An upward flow is generated in the carrier feed channel 20 formed in the object 18.
Aerating means 24 to be insulated, and a tubular structure at the lower end of the tubular structure 18.
Provided treated water and carrier 1 that flow into cylindrical structure 18
4 (hereinafter referred to as “carrier mixture”) to carrier 1
4 to separate the treated water into the treated water flow path 22 side
Lean 26 and mixing of carrier flowing into carrier feed channel 20
The liquid and the carrier 14 separated by the screen 26 are mixed with the nitrification tank 1
A transfer water passage 28 for transferring to an upstream position A, and a treated water flow passage
Wastewater that feeds treated water flowing through 22 to the denitrification tank and the solid-liquid separation tank
And a flood channel 30. The cylindrical structure 18 includes an inner cylinder 32 and an outer cylinder 34.
And has a double pipe structure.
0, and the space between the inner cylinder 32 and the outer cylinder 34 is the treated water flow path 2.
2 and two flow paths 20 and 22 are formed.
The screen 26 is provided at the lower end of the tube 32. Ma
In addition, the lower end of the cylindrical structure 18 is provided with a carrier feed passage 20.
One inflow port 36 for inflow is formed, and two
The two outlets 38, 40 corresponding to the channels 20, 22 are shaped.
Is done. This tubular structure 18 has a double pipe structure.
The inside of the cylinder is not limited to
The two flow paths 20 and 22 may be formed by partitioning. The aeration means 24 has a plurality of nozzles.
A squeeze tube 42 is disposed at a substantially middle height position of the carrier feed passage 20.
Is done. The reason for arranging at approximately the middle height is that the aeration means 2
4 is generally between 6000 and 700
0 mmAq. The nozzle pipe 42 is
Blower 48 via pipe 44 and air flow control valve 46
Connected to. As a result, air rises from the nozzle pipe 42.
When aerated, bubbles rise due to aerated air
As a result, when the upward flow is generated in the carrier feed passage 20,
Then, a suction force is generated at the inflow port 36 of the tubular structure 18. Ma
In addition, carrier rises due to the rise of bubbles caused by aerated air.
An air lift action occurs in the flow path 20, which causes the liquid level to rise.
To rise. In this case, the liquid level of the carrier feed passage 20 is set in the nitrification tank.
Twelve liquid levels 54. The transfer water passage 28 has a base end 28A at the carrier feed.
The outlet 28 is connected to the outlet 38 at the upper end of the
B extends horizontally to near the upstream position A in the nitrification tank 12
Is done. As a result, the carrier flowing into the carrier feed passage 20
The mixed liquid flows through the carrier feed passage 20 by an air lift action.
Ascending, passing through the transfer channel 28 and located upstream in the nitrification tank 12
Flow to A. As a result, the carrier 14 in the carrier mixture is also nitrified.
It is transferred to an upstream position in the tank 12. The discharge channel 30 is opened at the upper end of the treated water channel 22.
Trough for receiving treated water overflowing from the released outlet 40
Part 50, the treated water overflowing to the trough part 50
A water channel 52 for flowing into the solid-liquid separation tank;
0 so that the upper end is higher than the liquid level 54 of the nitrification tank 12.
It is formed. Then, the treatment flowing into the treated water passage 22
Water depends on the difference in water level flowing into the nitrification tank 12 from the denitrification tank.
It is discharged into the solid-liquid separation tank through the discharge water channel 30 by the indentation force.
It is. When this pushing force is used, the treated water is
It cannot be circulated to a denitrification tank with a liquid level higher than 12.
No. Therefore, when it is necessary to circulate the treated water to the denitrification tank
A pit is provided between the discharge channel 30 and the solid-liquid separation tank.
To circulate the treated water in this pit to the denitrification tank.
A circulation pump (not shown) may be provided. An opening / closing bar is provided at the top of the carrier feed passage 20.
An air vent pipe 56 with a lube 55 is provided to feed the carrier.
Evacuate the air accumulated in the top space by rising inside the flow path 20
You. This prevents the pressure in the top space from rising.
As it is possible, the liquid level is effectively raised by the air lift function
Can be done. The upper end is open around the lower part of the cylindrical structure 18.
A released guide cylinder 58 is provided. This guide cylinder 58
The carrier mixed liquid flowing from the upstream side of the nitrification tank 12
It serves to guide up to the inlet 36 of the structure 18. The cleaning of the screen 26 is performed by the treatment water flow.
Processed water that rises in channel 22 and rises in carrier feed channel 20
With the carrier 14 to be used. That is, the screen 26
And flows from the carrier feed channel 20 side to the treated water channel 22 side.
The treated water is applied to the outer surface of the screen 26 by the screen 2.
As it rises along the six faces,
The screen can be washed. Furthermore, this treated water
Of the carrier 14 clogged with the screen 26
Can also be removed. On the other hand, the carrier feed passage 20
The ascending carrier 14 screens the inner surface of the screen 26.
Rises along the -26 and rubs the inner surface of the screen 26
Therefore, the screen 26 can be cleaned. to this
It is possible to suppress the increase in the flow resistance of treated water.
it can. In this case, a number of nozzles are provided below the screen 26.
It is possible to dispose a screen washing tube 60 having a swarf.
Wear. The screen washing pipe 60 is provided with an air pipe 62 and
Connected to a blower 66 via an air flow control valve 64
From the screen washing tube 60 along the screen 26 surface
Air is aerated. This allows the aerated air to
As bubbles rise along the surface of the screen 26 and rise
Activated soil adhering to the screen 26 due to the shearing force of air bubbles
Removes deposits such as mud. Therefore, the screen 26 is
Layer clogging is difficult. Furthermore, this screen washing tube
The rising of the bubbles generated from 60 and the carrier 14
Washing of the screen 26 by the synergistic effect of the action of rubbing the six surfaces
The purification effect can be made more effective. Furthermore,
If the screen 26 is a vertical screen, bubbles and carriers
14 rises along the vertical line of the screen 26,
The cleaning effect can be further improved. Next, the carrier separating apparatus constructed as described above
The operation of No. 16 will be described. Flow from the denitrification tank to the upstream position A in the nitrification tank 12
The wastewater that has entered contacts the carrier 14 and the activated sludge in the nitrification tank 12.
While being touched and being subjected to nitrification treatment, it flows downstream in the nitrification tank 12.
It is. The carrier is also moved from upstream to downstream with the flow of this wastewater.
Flowing to the side. Nitrified with the carrier 14 flowing downstream
The carrier mixture of the treated water is generated by the upward flow in the cylindrical structure 18.
Is guided by the guide cylinder 58 due to the suction force generated.
Flows into the carrier feed passage 20 from the inlet 36 of the plate-shaped structure 18
I do. Of the flowed carrier mixture, the treated water flow path 22 side
The carrier mixture to be flown is carried by the screen 26.
The body 14 is separated and only the treated water passes. This
Thus, separation of the treated water and the carrier 14 is performed. Meanwhile, carrier
The carrier mixture flowing on the side of the feed channel 20 is screened.
Along with the carrier 14 separated by the
In the nitrification tank 12 through the transfer channel 28 by the lift action
To the upstream position A. Thereby, the carrier 14 is transferred.
Is performed. The treated water that has passed through the screen 26
Is driven by the pushing force of wastewater from the denitrification tank to the nitrification tank 12.
After overflowing to the dewatering section 50, it passes through the waterway section 52 and is fixed
Flow into the liquid separation tank. [0029] Thereby, the charge flowing from the upstream side to the downstream side is changed.
Since the body 14 is returned to the upstream position A, the carrier concentration in the nitrification tank is reduced.
The cloth can be made uniform and the carrier 14
Can be prevented from flowing out of the nitrification tank 12
it can. In the present invention, the carrier separation device 16
Is an integrated structure combining the transfer means and the separation means for the carrier 14.
The conventional transfer means and separation means are provided separately.
Can be made much more compact than in the case of
Therefore, the installation space can be reduced, and
Can be easily installed in a small space at the downstream position B
In both cases, equipment costs can be reduced. Further, according to the present invention, the treated water
The carrier is separated on the screen using the flow over the trough.
Instead of separating, the screen 26 is
It is provided at the lower end and uses the upward flow on the treated water flow path 22 side to process.
The screen 2 is formed from the mixed liquid that is going to flow into the water passage 22.
6, the carrier 14 was separated. That is, the treated water channel
Due to the upward flow generated at 22, the treated water is turned into screen 26.
The water flowed into the treated water flow path 22 through the entire surface. Subordinate
Therefore, even if the screen area is smaller than
In addition to increasing the amount of water passing through the lean 26,
The entire surface of the clean 26 can contribute to the separation of the carrier 14
it can. In addition, the carrier feed passage 20 and the treated water passage 22
By adjusting the upward flow velocity balance,
Emission of water can be increased or decreased. Subordinate
Thus, the carrier separation device 16 is moved to the downstream position B of the nitrification tank 12.
If installed and used, the discharged amount of treated water can be easily increased.
Therefore, it is possible to improve the nitrification performance of the carrier 14.
From the nitrification tank 12 with untreated wastewater
No spills. As described above, the carrier separation device 16 of the present invention
According to the transfer, separation of the carrier 14 and the treatment water to the denitrification tank,
The three functions of circulation can be performed by one carrier separation device 16.
Can be. FIG. 2 shows a carrier separation device 16 of the present invention.
For explaining a second embodiment of the wastewater treatment apparatus 10
FIG. 4 is a front view of the wastewater treatment apparatus 10 according to the second embodiment.
Of a shallow tank type nitrification tank with a depth of about 5m
An example in which the carrier separation device 16 is provided substantially at the center will be described.
Note that the same members and devices as described in the first embodiment are used.
Are denoted by the same reference numerals, and detailed description is omitted.
You. In the second embodiment, a cylindrical screen 2
6 is provided at the lower end of the outer cylinder 34 of the tubular structure 18.
In addition, a guide cylinder 58 is provided outside the screen 26. This
As a result, the carrier mixture flowing into the guide cylinder 58 is
After flowing down in the id cylinder 58 as a downward flow, the cylindrical structure 1
8 forms a return channel that reverses at the inlet of 8 and becomes upward flow
You. The screen 26 is installed at a location
Install at the inlet of the cylinder where the suction force can be used rather than in the middle of the flow
Preferably. Therefore, as described above, the guide cylinder 58
And the screen 26 to form a folded flow path.
Separation performance of the carrier even in a shallow tank type nitrification tank with a shallow water depth.
Can be increased. As a result, the flow
The carrier 14 in the mixed carrier mixture is separated by the screen 26
As a result, only the treated water flows into the treated water channel 22. Also,
The separated carrier 14 and the carrier mixture are mixed in a carrier feed channel 20.
Flows into. Also, in the case of the second embodiment, the first
As in the embodiment, the nozzle is provided only in the carrier feed passage 20.
A tube 42 was provided. And the upward flow of the treated water flow path 22
Due to the difference in water level of wastewater flowing into the nitrification tank 12 from the denitrification tank
The pushing force is used. Thereby, the treated water flow path
The treated water that has flowed into the tank 22 passes through the discharge channel 30 and is separated into solid and liquid components.
It is discharged to the separation tank. If this pushing force is used,
Circulate water for denitrification with higher liquid level than nitrification tank 12
It is not possible. Therefore, it is necessary to circulate the treated water to the denitrification tank.
If necessary, as described in the first embodiment
A pit is provided between the discharge channel and the solid-liquid separation tank
Circulation pons for circulating treated water in the pit to the denitrification tank
May be provided. In the case of the second embodiment, the screen 26
Is washed downward between the screen 26 and the guide cylinder 58.
Up the wastewater and carrier 14 flowing as
It is carried out with treated water flowing as countercurrent. In other words, wastewater and
The body 14 mainly cleans the outer surface of the screen 26,
The treated water mainly cleans the inner surface of the screen 26.
In this case, the first embodiment is provided below the screen 26.
Similarly, a screen cleaning tube 60 can be provided. I
The wastewater flowing between the screen 26 and the guide cylinder 58
Since the direction of the flow is downward,
A where the rise does not hinder the downward flow of wastewater.
is necessary. In the second embodiment, the cylindrical structure 1
8, four transfer water passages 28 are provided on all sides of the nitrification tank 12,
The carrier 14 flowing in the carrier feed channel 20 is located on all sides of the processing tank.
It was distributed. The second embodiment of the present invention configured as described above
In the case of the embodiment, the same effect as in the first embodiment can be obtained.
Can be. FIG. 3 shows a carrier separation device 16 of the present invention.
Longitudinal section for explaining a third embodiment of the wastewater treatment apparatus 10
FIG. The third embodiment is different from the first embodiment.
Similarly, a screen 2 is provided at the lower end of the inner cylinder 32 of the tubular structure 18.
6 and both the carrier feed passage 20 and the treated water passage 22
On the other hand, the nozzle pipes 42, 42 are provided. The third embodiment of the present invention constructed as described above
In the case of the embodiment, the same effect as in the second embodiment can be obtained.
Can be. Further, in the third embodiment, the treated water flow path
A nozzle tube 42 is also provided on the nozzle 22 so that the air
The liquid level of the treated water channel 22 can be higher than the liquid level of the denitrification tank.
So that the treated water is not only nitrified
It can be circulated to a denitrification tank with a higher liquid level than tank 12.
Wear. Therefore, circulation for circulating the treated water to the denitrification tank
Running cost can be reduced because no pump is required
Wear. In this embodiment, the processing tank is made of nitric acid.
The case of the nitrification tank 12 in which the carrier 14 supporting the
As described above, the carrier 14 is not limited to this.
Transfer means for transferring in the processing tank and processing for discharging from the processing tank
All that requires separation means to separate the carrier 14 from the water
Of wastewater treatment equipment. The carrier 14 and the activated sludge are placed in the nitrification tank 12.
Has been described, but the carrier 14 alone may be used. [0045] As described above, the carrier separation according to the present invention is carried out.
According to the device, the transfer means and the separation means for the microorganism carrier are combined.
The conventional transfer means and separation means
Can be made much more compact than if the
Can be. Therefore, the installation space can be reduced.
Easy installation in small space downstream of processing tank
In addition, equipment costs can be reduced. Further, according to the present invention, the treated water
The carrier is separated on the screen using the flow over the trough.
Instead of separating, place the screen on the lower end of the tubular structure.
Installed on the treated water flow path side using the upward flow of the treated water flow path side.
Microbial carriers are screened from the mixture to be flowed.
And the upward flow generated in the treated water flow path.
The treated water flows into the treated water flow path through the entire screen.
To enter. Therefore, the screen area is smaller than before.
Even if they are all small, increase the amount of treated water passing through the screen.
And the entire screen contributes to carrier separation.
Can be made. In addition, the carrier feed channel and the treated water channel
By adjusting the upward flow velocity balance,
Discharge of treated water can be increased or decreased. Also, the carrier feed passage passing through the screen
Water flowing from the side to the treated water flow path side
Along with the water,
Can be washed. Furthermore, this treated water rises
Removes carriers that are clogged on the screen.
Can be. This increases the flow resistance of the treated water
Can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view for explaining a first embodiment of a wastewater treatment apparatus provided with a carrier separation device of the present invention. FIG. 2 is a wastewater provided with a carrier separation device of the present invention. FIG. 3 is a longitudinal sectional view for explaining a second embodiment of the treatment apparatus. FIG. 3 is a longitudinal sectional view for explaining a third embodiment of the wastewater treatment apparatus provided with the carrier separation device of the present invention. FIG. 5 is a diagram illustrating a process of a modified circulation method. FIG. 5 is a configuration diagram of a nitrification tank provided with a conventional carrier separation device including a transfer unit and a separation unit. 14 ... Carrier, 16
... Carrier separation device, 18 ... Cylinder structure, 20 ... Carrier feed channel, 22 ... Treatment water channel, 24 ... Aeration means, 26 ... Screen, 28 ... Transfer channel, 30 ... Discharge channel, 32 ... Inner cylinder,
34: outer cylinder, 36: inlet of cylindrical structure, 38: outlet of carrier feed channel, 40: outlet of treated water channel, 42: nozzle tube, 50: trough portion of discharge channel, 52: discharge Aqueduct part of a waterway, 54 ... Liquid level of nitrification tank, 58 ... Guide cylinder, 60 ...
Screen washing tube

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shigeki Kobayashi 1-1-1-14 Uchikanda, Chiyoda-ku, Tokyo Hitachi Plant Construction Co., Ltd. (56) References JP-A-10-5778 (JP, A) JP-A-10-146596 (JP, A) JP-A-7-284793 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C02F 3/02-3/10

Claims (1)

(57) [Claims 1] A transfer means for transferring microbial carriers in a treatment tank for biologically treating wastewater in the treatment tank and treated water discharged from the treatment tank. In a carrier separation device provided with separation means for separating the microorganism carrier, a cylindrical body vertically disposed in the treatment tank, having an inlet at a lower end and an outlet at an upper end, and an inner cylinder and an outer cylinder. Two depending on the tube
A heavy cylinder structure, the inside of the inner cylinder, and the inner cylinder and the outer cylinder
One of the spaces is a carrier feed channel and the other is a treated water channel.
And a cylindrical structure formed from the two flow paths, provided in the carrier feed flow path of the two flow paths, and aerating the air into the carrier feed flow path by an air lift action of the air. Aeration means for generating an upward flow in the carrier feed flow path and making the liquid level in the flow path higher than the liquid level in the treatment tank, provided at the lower end of the tubular structure, Among the mixed liquid of the treated water and the microorganism carrier flowing into the tubular structure, a screen that separates the microorganism carrier from the mixed solution that is going to flow into the treated water channel side and allows only the treated water to pass therethrough, A transfer channel that is communicated with the outlet on the carrier feed channel side and that transfers the mixed liquid that has flowed into the carrier feed channel to a desired position in the processing tank by the air lift function, and an outlet of the process water channel. Before being flowed into the treated water flow path A discharge channel for forming the upward flow in the treated water flow path by the indentation force due to the difference in water level between the front and rear of the treatment tank and discharging the treated water out of the treatment tank; and the transfer means and the separation means. And a carrier separation device.