JP3271882B2 - Septic tank - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a purification tank provided with a sludge storage tank for storing sludge generated in the tank.

[0002]

2. Description of the Related Art Conventionally, in this type of septic tank, the sludge storage tank is simply provided with a space for storing sludge.

[0003]

Usually, the sludge stored in the sludge storage tank is configured to be able to suppress an increase in the amount of sludge in the tank by periodically pulling the sludge out of the tank. According to the conventional sludge storage tank described above, since it is configured to simply store sludge, it is difficult to increase the concentration of sludge even if it is allowed to settle and sediment even if it is allowed to stand still. When it comes to withdrawing, a large amount of sludge must be extracted to extract a predetermined amount of solid components, and frequent sludge extraction must be performed.
The disadvantage is that a great deal of labor has to be spent on maintenance.

[0004] Accordingly, an object of the present invention is to provide a septic tank capable of performing a drawing operation after concentrating sludge at a high concentration in view of the above-mentioned drawbacks.

[0005]

To achieve the above object, the present invention is characterized in that a filtration membrane device (C1) for filtering water to be treated is provided above the sludge storage tank (N2), Sludge storage tank (N2) to sludge storage tank (N2)
A filtration water transfer pipe (A6) for transferring filtered water filtered by the filtration membrane device (C1) to another tank adjacent to the filtration membrane device (C1), and connected to the filtration membrane device (C1); (N2)
Water level of the other tank is set higher than the water level of the other tank.
Transfer the treated water transfer pipe (A6) to the water in the sludge storage tank (N2).
And below the filtration membrane device (C1).
A diffuser tube (D1) is provided on the side of the filter membrane device (C1).
Screen for solid-liquid separation of water to be treated supplied below
(C3), and below the screen (C3),
A diffuser (D) for supplying air bubbles to the screen (C3)
2) . In addition, sludge storage tank (N2)
And next to membrane separation tank (E2) and sludge storage tank (N2)
A septic tank provided with another tank in contact with the tank,
The solids obtained by solid-liquid separation of the water to be treated
A screen filtration device (S) for transferring to the detention tank (N2) is installed.
And a settling sludge transfer pipe (A) for returning the settled sludge settled at the bottom of the membrane separation tank (E2) to the sludge storage tank (N2).
4), a filtration membrane device (C1) for filtering the water to be treated is installed above the sludge storage tank (N2), and another from the sludge storage tank (N2) adjacent to the sludge storage tank (N2). The tank may be provided with a filtered water transfer pipe (A6) for transferring filtered water filtered by the filtration membrane device (C1), and may be connected to the filtration membrane device (C1). N2)
And next to membrane separation tank (E2) and sludge storage tank (N2)
A septic tank provided with another tank in contact with the tank,
The solids obtained by solid-liquid separation of the water to be treated
A screen filtration device (S) for transferring to the detention tank (N2) is installed.
The sludge settling at the bottom of the membrane separation tank (E2).
Serial sludge storage tank (N2) Return sent to precipitate the sludge transfer pipe (A
4), a filtration membrane device (C1) for filtering the water to be treated is installed above the sludge storage tank (N2), and another from the sludge storage tank (N2) adjacent to the sludge storage tank (N2). The tank is provided with a filtered water transfer pipe (A6) for transferring filtered water filtered by the filtration membrane device (C1), and is connected to the filtration membrane device (C1), and a water level of the sludge storage tank (N2) is provided. To
Set the water level higher than the other tank, and transfer the water to be treated.
Install the pipe (A6) below the water level of the sludge storage tank (N2).
And a diffuser below the filtration membrane device (C1).
(D1) provided and supplied below the filtration membrane device (C1)
Screen (C3) for solid-liquid separation of treated water
Below the screen (C3).
A diffuser (D2) for supplying air bubbles to the housing (C3) may be provided . The operation and effect are as follows.

[Effects] That is, according to the above-described structure,
Since the sludge in the sludge storage tank is solid-liquid separated by the filtration membrane device, water is extracted from the sludge storage tank to another water treatment tank,
Since the solid component that can be subjected to water treatment and solid-liquid separated remains in the sludge storage tank, the sludge in the sludge storage tank can be concentrated to a high concentration. Therefore, when the septic tank is maintained, the sludge in the sludge storage tank can be extracted in a high-concentration state, and the sludge in the septic tank can be sufficiently removed with a small amount of extraction. In addition, since sludge is accumulated in a high concentration state, even a small sludge storage tank can accumulate sludge for a long time, so that the septic tank can be operated stably without much maintenance. Become,
The labor required for maintenance can be reduced, and the septic tank can be made small as a whole, so that the construction of the septic tank can be facilitated.

Further, if the filtration membrane device is disposed above the sludge storage tank, the supernatant of the sludge precipitated and concentrated in the sludge storage tank can be separated into solid and liquid, and the sludge concentration can be efficiently performed. Can be performed. Further, if the water level of the sludge storage tank is set higher than the water level of the other tank, and the treated water transfer pipe is provided at a level lower than the water level of the sludge storage tank, suction is particularly performed to the filtration membrane device. Without providing a filtration membrane device, the sludge in the sludge storage tank can be constantly concentrated. In this configuration, if an air diffuser is provided below the filtration membrane device, even if dirt adheres to the filtration membrane device, the bubbles generated by the air diffusion device collide with the filtration membrane device. Since the dirt is prevented from being fixed to the filtration membrane device while the dirt is being stripped from the filtration membrane device, the function of concentrating the water to be treated can be maintained for a long time. In the sludge storage tank, odor is likely to be generated, but the air bubbles due to diffused air also help to remove odor. In addition, if a screen for solid-liquid separation is provided below the filtration membrane device, it is possible to prevent relatively large solid components from adhering to the filtration membrane device and to prevent inconvenience such as clogging of the filtration membrane device. It's easy to do. In addition, the script
Diffuser for supplying air bubbles to the screen below the screen
If an upflow is established in the sludge supernatant in the sludge storage tank,
Formed on the filter and the screen.
Odor components in the sludge storage tank
Can be relaxed by oxidative removal. The sludge storage tank and
And other tanks adjacent to the membrane separation tank and sludge storage tank
In a certain septic tank, the water to be treated from the other tank is fixed.
Transfer the solid obtained by liquid separation to the sludge storage tank
By providing a screen filtration device, the other tank
From which the solid matter is preferentially transferred to the sludge storage tank and stored,
The solid component can be stored at a higher concentration. The membrane
Settled sludge settling at the bottom of the separation tank is returned to the sludge storage tank
Solids as the main component
The sedimentation sludge to be deposited and concentrated in the sludge storage tank,
Components that may adversely affect water treatment in the membrane separation tank
Can be stored and concentrated by precipitation.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the septic tank of the present invention is provided with mirror sections X1 and X2 at both ends of a cylindrical septic tank main body X to form an enclosed space inside, and is provided with a partition wall in the enclosed space. Then, from the upstream side, a flow control tank N1, a denitrification tank E1, a sludge storage tank N2, a membrane separation tank E2, and a discharge pump tank T are formed, and a manhole used for maintenance and the like is provided above each of the tanks. H is provided.

The flow control tank N1 is provided with the purifying tank main body X.
An anaerobic bacterium that grows inside receives the raw water to be treated that has flowed into the septic tank from the inflow port I provided in one of the mirror parts X1 and precipitates and removes impurities in the treated water. A first pump P1 for transferring the water to be treated to the denitrification tank E1 is provided in the water treatment chamber for temporarily storing the water to be treated while performing the anaerobic treatment of the water to be treated, Even when there is no inflow of the water to be treated for a long period of time, the water to be treated is constantly transferred to the denitrification tank E1 so as not to hinder the water treatment in each of the subsequent water treatment chambers.

The denitrification tank E1 is provided with the flow control tank N1.
An inflow pipe A1 for inflowing the water to be treated from the flow rate adjusting tank N1 into the water treatment chamber adjacent to the first pump P1 is provided to form an inflow passage of the water to be treated. Further, a second pump P2 is provided inside, and a transfer pipe A2 is provided in the second pump P2 to transfer the water to be treated to the membrane separation tank E2. In addition, a stirring pump P3 for stirring and circulating the water to be treated in the tank is provided to mix the water to be treated in the tank and mix the water to be treated with a high BOD load with the nitrified water to be treated. In addition, it is configured to perform advanced denitrification processing.

In the membrane separation tank E2, the inflow path is provided in a partition separating the denitrification tank E1, and the water to be treated excessively flowing from the denitrification tank E1 is supplied to the denitrification tank E1. A return pipe A3 for returning is provided to constitute a return path of the water to be treated. Further, a membrane separation device M in which a large number of flat filtration membrane plates are arranged in parallel in an upright state is installed, and the membrane separation device M is a filtration device that aligns and holds a large number of filtration membrane plates. A membrane plate holding frame is provided, and a leg for supporting the filtration membrane plate holding frame is provided at a lower portion, and air bubbles are supplied to the filtration membrane plate between the legs, so that sludge or the like adheres excessively to the membrane surface. And a diffuser D for supplying oxygen to the water to be treated while forming a circulating flow in the membrane separation tank E2. In addition, an intake pipe M1 is connected to each filtration membrane plate of the membrane separation device M, and a water collection pipe M2 that joins filtered water from the intake pipe M1 and guides the filtered water to the outside of the membrane separation tank E2 is connected. In addition, it is connected to a discharge pump tank T adjacent to the membrane separation tank E2 below the water surface of the membrane separation tank E2. Further, the membrane separation tank E2 is provided with a settling sludge transfer pipe A4 for transferring the settled sludge to the sludge storage tank N2 by an air lift action.

The sludge storage tank N2 is provided with the denitrification tank E1.
And the membrane separation tank E2, a water treatment space is provided separately. Above the sludge storage tank N2, a transfer pipe A2 for transferring the water to be treated from the denitrification tank E1 to the membrane separation tank E2 is disposed in a horizontal posture. A screen filtration device S for solid-liquid separation is provided above the sludge storage tank N2 of the transfer pipe A2. As shown in FIGS. 2 and 3, the screen filtering device S includes a comb-shaped screen S1 including a plurality of comb teeth S1a for solid-liquid separation;
A roller S2 that scrapes solid matter caught on the comb-shaped screen S1 by inserting a large number of protrusions S2a between 1a.
Among the water to be treated transferred through the transfer pipe A2, a relatively large solid component is filtered by the comb screen S1, and the water to be treated that has passed through the comb teeth S1a is The solid matter transferred to the membrane separation tank E2 and caught on the comb teeth S1a is transferred to the roller S2.
, And finally dropped into the sludge storage tank N2, and the solid matter is accumulated in the sludge storage tank. Further, the settling sludge transfer pipe A4 is provided between the membrane separation tank E2 and the sludge storage tank N2, and the relatively high concentration of settled sludge settled at the bottom of the membrane separation tank E2 is transferred to the settling sludge. Tube A4
Thus, the sludge is returned to and stored in the sludge storage tank N2. Further, as shown in FIG. 1, a filtration membrane device C for filtering the water to be treated is provided above the sludge storage tank N2.
1 and a filtered water transfer pipe A6 for transferring filtered water filtered by the filtration membrane device C1 from the sludge storage tank N2 to the denitrification tank E1. The filtration water transfer tube A6 is connected to the filtration membrane device C1. is there. The filtration membrane device C1 is covered with a casing C2 whose upper and lower ends are open, and a screen C3 made of punched metal is provided at a lower opening of the casing C2 so that coarse solid components can be removed by the filtration membrane. The device is configured to prevent it from adhering to the device C1. An air diffuser D that supplies air bubbles to the filtration membrane device C1 below the filtration membrane device C1 in the casing C2.
1 is provided below the screen C3, and an air diffuser D2 for supplying air bubbles to the screen C3 is provided to form an upward flow in the sludge supernatant and adhere to the filtration membrane device C1 and the screen C3. While removing the dirt
The configuration is such that the odor components in the sludge storage tank N2 can be mitigated by oxidative removal. Incidentally, the water level of the sludge storage tank N2 is set to be higher than the water level of the normal denitrification tank E1, and a check valve A7 is connected to the filtrate water transfer pipe A6.
Is provided to prevent the water to be treated in the denitrification tank E1 from flowing backward.

With such a configuration, the sludge storage tank N2
Inside, the solid components from the screen filtration device S,
The sludge from the membrane separation tank E2 and the like (hereinafter simply referred to as sludge and the like) and components that may adversely affect water treatment are stored, sedimented and concentrated, and the sludge storage is performed by the filtration membrane device C1. By returning the filtered water solid-liquid separated from the supernatant of the sludge storage tank N2 to the denitrification tank E2 due to the head difference between the tank N2 and the denitrification tank E1, it becomes possible to further concentrate the solid component. It can be stored at a high concentration, and can be efficiently performed when pulling out sludge or the like.

The discharge pump tank T comprises a disinfecting tank Q1 and a storage tank Q2. The disinfecting tank Q1 has a treated water receiving container on a partition separating the membrane separation tank E2 and the discharge pump tank T. It is configured by providing a small hole in the wall surface,
The filtered water that has flowed into the disinfection tank Q1 flows into the storage tank Q2 after being disinfected. The storage tank Q2 is provided with a third pump P
After storing the treated water, the treated water is pumped up by the discharge pump P1 and discharged from the discharge port Z to the outside of the purification tank via the discharge pipe A5. Thereby, the disinfected treated water is almost quantitatively discharged from the storage tank T to the outside of the purification tank.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a vertical side view of a septic tank.

FIG. 2 is an overall perspective view of a screen filtration device.

FIG. 3 is a plan view of a main part of the screen filtration device.

[Explanation of symbols]

 A6 Treated water transfer pipe C1 Filtration membrane device C3 Screen D1 Aeration pipe N2 Sludge storage tank

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazuyuki Honda 1 at 2, Takamatsu, Kosai-cho, Koga-gun, Koka-gun, Shiga Prefecture Inside the Kubota Shiga Plant (72) Katsumi Hamada 2, Takamatsu, Kosai-cho, Koga-gun, Shiga (1) Inside Kubota Shiga Plant, Ltd. (72) Inventor Shinichi Furuse Inside Kubota Shiga Plant, 2 at Takamatsu, Kosai-cho, Koga-gun, Shiga Prefecture (56) References JP-A-7-256294 (JP, A) JP-A-6-179000 (JP, A) JP-A-4-341394 (JP, A) JP-A-3-114585 (JP, A) JP-A-7-290075 (JP, A) JP-A-4-57202 ( JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) C02F 3/00

Claims (3)

(57) [Claims] 1. A purification tank provided with a sludge storage tank (N2), wherein a filtration membrane device (C1) for filtering water to be treated is installed above the sludge storage tank (N2), and the sludge storage tank (N2) is provided. A filtration water transfer pipe (A6) for transferring filtered water filtered by the filtration membrane device (C1) is provided from N2) to another tank adjacent to the sludge storage tank (N2), and the filtration membrane device (C1) is provided. continuously provided in, the water level of the sludge storage tank (N2), the water level of the other tank
And the treated water transfer pipe (A6) is connected to the sludge storage tank (N
A water diffuser (D1) is installed below the filtration membrane device (C1) while being provided below the water level of 2).
The processing target supplied below the filtration membrane device (C1)
A screen (C3) for solid-liquid separation of water is provided, and the screen (C3) is provided below the screen (C3).
A septic tank provided with a diffuser (D2) for supplying air bubbles to (C3) . 2. A sludge storage tank (N2) and a membrane separation tank (E).
2) and a purification tank provided with another tank adjacent to the sludge storage tank (N2) , wherein a solid obtained by solid-liquid separation of the water to be treated from the other tank is provided.
Screen filtration for transferring material to the sludge storage tank (N2)
An apparatus (S) is provided, and the settled sludge settled at the bottom of the membrane separation tank (E2) is treated with the sludge.
Settling sludge transfer pipe (A4) returned to mud storage tank (N2)
And a filtration membrane device (C1) for filtering the water to be treated is provided above the sludge storage tank (N2), and the sludge storage tank (N2) is provided in another tank adjacent to the sludge storage tank (N2). A purification tank provided with a filtered water transfer pipe (A6) for transferring filtered water filtered by the filtration membrane device (C1), and connected to the filtration membrane device (C1). 3. A sludge storage tank (N2) and a membrane separation tank (E).
2) and a purification tank provided with another tank adjacent to the sludge storage tank (N2) , wherein a solid obtained by solid-liquid separation of the water to be treated from the other tank is provided.
Screen filtration for transferring material to the sludge storage tank (N2)
An apparatus (S) is provided, and the settled sludge settled at the bottom of the membrane separation tank (E2) is treated with the sludge.
Settling sludge transfer pipe (A4) returned to mud storage tank (N2)
And a filtration membrane device (C1) for filtering the water to be treated is provided above the sludge storage tank (N2), and the sludge storage tank (N2) is provided in another tank adjacent to the sludge storage tank (N2). A filtration water transfer pipe (A6) for transferring filtered water filtered by the filtration membrane device (C1) is provided, connected to the filtration membrane device (C1), and the water level of the sludge storage tank (N2) is set to the level. The water level of the other tanks
And the treated water transfer pipe (A6) is connected to the sludge storage tank (N
A water diffuser (D1) is installed below the filtration membrane device (C1) while being provided below the water level of 2).
The processing target supplied below the filtration membrane device (C1)
A screen (C3) for solid-liquid separation of water is provided, and the screen (C3) is provided below the screen (C3).
A septic tank provided with a diffuser (D2) for supplying air bubbles to (C3) .