JPH11104673A - Septic tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a septic tank wherein water in the tank can be circulated without performing unnecessary pumpage by using an air lift pump. SOLUTION: A septic tank has a constitution wherein the inside of the tank is divided by partition walls and an anaerobic filter bed tank, an aerobic filter bed tank, a treating water tank or a precipitation tank and a disinfection tank are arranged in this order. In this case, a transferring device for circulating water in the aerobic filter bed tank, the treating water tank or the precipitation tank to the anaerobic tank is an air lift pump type and a throttling part 24 with an opening movable in a pipe is provided in a suction hole of the air lift pump and the air lift pump 11 is worked to transfer pumped water in the tank to the anaerobic filter bed tank.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewage treatment tank for treating night soil and domestic wastewater, and more particularly to a device for transferring water in the tank.

[0002]

2. Description of the Related Art A conventional sewage purifying tank will be described with reference to FIG. 3. A sewage purifying tank 1 is divided by partition walls 2, 3, 4, and 5, and an anaerobic filter bed tank is provided from an upstream side. One chamber 6, anaerobic filter bed second chamber 7, aerobic filter bed tank 8, treated water tank 9 (sometimes a sedimentation tank), and disinfection tank 10 are arranged in this order. Then, in order to stabilize the quality of the treated water and remove nitrogen, the water in the treated water tank 9 is pumped up by the air lift pump 11 and circulated (returned) to the first chamber 6 of the anaerobic filter bed tank. Circulation is not limited to the water in the treatment water tank 9 as shown in FIG. 3, but may be the water in the aerobic filter bed tank 8 or the sedimentation tank.

Since the amount of water circulated from the treatment water tank 9 to the first chamber 6 of the anaerobic filter bed tank is extremely small (several liters / minute), a commercially available submersible pump cannot be used, and an air lift pump 11 using air as a driving force is used. Use pumping and circulating.

[0004] As shown in FIG. 4, a distribution metering device 12 for adjusting the amount of circulating water is provided above the air lift pump 11.
Is installed. The pumping mechanism of the air lift pump 11 is such that air 14 blown from the inner pipe 13 is discharged from the bottom and rises between the outer pipe 15 and the inner pipe 13, and at that time, the inside of the tank outside the outer pipe 15 The water 16 is also sucked and pumped to the distribution and metering device 12.

[0005] The distribution metering device 12 comprises a triangular weir 17 for measuring circulating water 18 and a return weir 19 for adjusting the amount of circulating water. The water 16 in the tank is pumped excessively by the air lift pump 11, and only the necessary amount of circulating water flows from the triangular weir 17. The circulating water amount is adjusted by changing the height of the return weir 19, and the excess water 20
It is to return to the original tank that was overflowed and pumped.

[0006]

In the prior art, the purpose of excessively pumping the water 16 in the tank is to change the gap width between the outer pipe 15 and the inner pipe 13 when pumping only the required amount of water.
That is, it is necessary to adjust the amount of pumped water by changing the resistance. At a low level such as several liters / minute, the gap width becomes extremely small, so that the gap is partially closed by sludge or the like. This is to avoid the phenomenon that pumping is not possible.

[0007] Therefore, the dispensing and weighing device 1 as described above.
2 is installed in the air lift pump 11 to cope with it. However, since the setting of the circulating water amount is performed while finely adjusting the height of the return weir 19 and measuring the circulating water 18 flowing from the triangular weir 17 using a container, the operation is extremely complicated. Also, even if the height of the return weir 19 can be finely adjusted, sludge easily adheres to the triangular weir 17 and the return weir 19, and the height of each weir changes depending on the amount of sludge attached. As a result, there is a problem that the circulating water amount is different from the initial setting, and a stable shift cannot be performed.

In view of the above problems, the present invention eliminates the need for the conventional dispensing and metering device 12 and enables the transfer of a small amount of circulating water of several liters / minute to be performed stably. An object of the present invention is to provide a sewage septic tank incorporating a sewage treatment tank.

[0009]

The present invention has been described with reference to FIGS.
As shown in, the inside of the tank is partitioned by partition walls 2, 3, 4, and 5,
In the purification tank arranged in the order of anaerobic filter bed tank, aerobic filter bed tank 8, treated water tank 9 or settling tank, and disinfection tank 10 from the upstream side,
The transfer device that circulates the water in the aerobic filter bed tank 8, the treatment water tank 9 or the sedimentation tank to the anaerobic filter bed tank is an air lift pump system, and can be moved in the pipe to the suction port of the air lift pump 11. It is characterized in that a diaphragm 24 having an opening is provided.

That is, a throttle 24 which can move in the pipe and has an opening is provided at the suction port of the air lift pump 11, and the pumping capacity of the air lift pump 11 is determined by the size of the opening of the throttle 24, and The sludge adhering to the inside of the pipe is removed by moving the squeezing section 24 to perform stable water pumping, and the pumped water is transferred to the anaerobic filter bed tank.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The amount of water pumped by an air lift pump 11 is determined by the immersion depth between the water surface and its lower end, the pipe diameter, the head, and the amount of air. It is an extremely small level of several liters / minute.

[0012] Usually, the air lift pump is used in a region where the amount of pumped water is large. Therefore, when the amount of pumped water is small, its adjustment is not easy. Therefore, the air lift pump 11 itself is provided with a throttle portion 24 (resistance portion) at the suction port while having an excessive water pumping capacity, thereby obtaining a target water pumping amount.

The opening diameter φD of the throttle unit 24 can be arbitrarily determined, and is individually changed in accordance with the target pumping amount. The throttle portion 24 is provided at a suction port of the air lift pump 11, and the inner pipe 13 of the air lift pump 11 is provided.
Suspended by a support member 25 connected to the Here, the support member 25 has a passage having an area larger than the opening diameter φD of the throttle unit 24 so that the discharge of the air 14 to be inserted and the pumping of the water 16 rising through the throttle unit 24 are not limited. Shape.

Further, an air lift pump 1 used in the present invention
In the structure of FIG. 1, when it is desired to reduce the pumping capacity while keeping the opening diameter φD of the throttle unit 24 constant, the air
This can be achieved by setting the opening where the air 14 is discharged from the inner pipe 13 toward the outer pipe 15, that is, the opening where the air 14 is discharged from the inner pipe 13 at a shallower position relative to the water depth.

The inner pipe 13 and the outer pipe 1 of the air lift pump 11
5 or the passage of the support material 25,
When sludge adheres to 4 and hinders the pumping of water in the tank, the sludge can be separated and removed by moving the inner pipe 13 up and down. Further, when the inner tube 13 is pulled up, the support member 25 and the throttle portion 24 connected thereto are also pulled up, so that each part can be easily cleaned. By these operations, stable pumping can be performed for a long time.

The entire amount of the pumped water in the tank is transferred to the anaerobic filter bed tank. However, as shown in FIG. 2, when a plurality of anaerobic filter bed tanks are provided, the inflow port 29 is provided to increase the treatment time. Is preferably transferred to the first anaerobic filter tank 1 chamber 6 which is closest to the anaerobic filter tank.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. The sewage purification tank 1 shown in FIG. 2 is partitioned by partition walls 2, 3, 4, and 5 from the upstream side, and the anaerobic filter tank first chamber 6, the anaerobic filter tank second chamber 7, the aerobic filter from the upstream side. The floor tank 8, the treatment water tank 9, and the disinfection tank 10 are arranged in this order. The anaerobic filter tank first chamber 6 and the anaerobic filter tank second chamber 7 are provided with filter media 21 and 22, and the aerobic filter tank 8 is provided with a microorganism adhering body 23.

The sewage 28 flowing from the inlet 29 into the first anaerobic filter tank 6 is processed through the second anaerobic filter tank 7 and the aerobic filter tank 8, and further through the treated water tank 9 to the disinfection tank. It is sterilized at 10 and discharged out of the system as treated water 31 from an outlet 30. Part of the water in the tank from the bottom of the aerobic filter tank 8 is pumped up by the air lift pump 11 for stabilization of the treated water quality and denitrification, and is circulated to the first anaerobic filter tank 6 by the transfer pipe 27. (Returned).

The air lift pump 11 is shown in FIG.
More specifically, using (a), the air lift pump 11 is installed in a treated water tank 9, and the bottom of the air lift pump 11 communicates with the bottom of the aerobic filter bed tank 8 through the partition wall 4. The air 14 inserted from the outside is discharged from the discharge portion 26 at the lower end of the inner tube 13 and passes through the passage of the support member 25, so that the outer tube 15 and the inner tube 13
Rise between. The propulsive force by which the air 14 rises raises water in the tank 16 from the bottom of the aerobic filter bed tank 8 through the squeezing section 24 and the passage of the supporting material 25 to rise between the outer pipe 15 and the inner pipe 13. . The pumped water is transferred from the transfer pipe 27 to the circulating water 1.
The process moves to the first anaerobic filter tank 6 as 8.

The air lift pump 11 has a property of pumping water in a stable state with no pulsation when air of a predetermined amount or more is inserted. In the present invention, too, the excess air 14 is fed so as to obtain a pumping capacity more than necessary. In. But,
The suction portion of the air lift pump 11, that is, the outer tube 1
At the lower end of 5, a throttle portion 24 having an opening of φD is previously suspended from the inner tube 13, so that a required amount of pumping water can be obtained stably.

FIG. 1B shows an air lift pump 11 according to another embodiment of the present invention, in which a discharge portion 26 of the air 14 inserted into the inner pipe 13 is provided above the lower end of the inner pipe 13. Show. That is, the air 14 to be inserted is discharged from the discharge portion 26 above the lower end of the inner tube 13. Note that the throttle portion 24 suspended from the inner tube 13 via the support member 25 is provided at the same position as when discharging from the lower end of the inner tube 13.

[0022]

As described above, according to the present invention,
Conventionally, the use of a dispensing and weighing device had a problem in adjusting and stabilizing the amount of transferred water, but by arranging the squeezing section having an opening so that it could be moved, it was possible to reduce It has become possible to make a stable transition even with the amount of pumped water.

[Brief description of the drawings]

FIG. 1 is an air lift pump which is a main part of the present invention;
(A) shows a cross-sectional view, and (b) shows a cross-sectional view of another embodiment.

FIG. 2 is a sewage purification tank showing an embodiment of the present invention,
(A) shows a horizontal sectional view, (b) shows A-
FIG.

FIG. 3 is a sectional view showing a conventional sewage purification tank.

FIG. 4 is a perspective view of a conventionally used dispensing and weighing device.

[Explanation of symbols]

1. Sewage septic tank 2. Partition wall 3. Partition wall 4. Partition wall 5. Partition wall 6. Anaerobic filter tank 1st room 7. 7. Anaerobic filter tank 2nd room Aerobic filter bed tank 9. Treatment water tank 10. Disinfection tank 11. Air lift pump 12. Dispensing and weighing device 1
3. Inner pipe 14. Air 15. Outer tube 16. Water in tank 1
7. Triangular weir 18. Circulating water 19. Return weir 20. Surplus water 21. Filter medium 22. Filter medium 23. Microbial adherent 24. Restrictor 25. Support material 26. Discharge unit 27. Transition tube 28. Sewage 29. Inlet 30. Outlet 31. Treated water

Claims (1)

[Claims] 1. A purification tank in which a tank is partitioned by a partition wall and an anaerobic filter bed tank, an aerobic filter bed tank, a treatment water tank or a sedimentation tank, and a disinfection tank are arranged in this order from an upstream side. The transfer device for circulating the water in the sedimentation tank or the treatment water tank to the anaerobic filter bed tank is an air lift pump system, and the suction port of the air lift pump is provided with a throttle unit having an opening movable in the pipe. Characterized sewage septic tank.