JP2594870B2 - Sewage septic tank - Google Patents

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, and more particularly to a method for dispersing suspended matters such as toilet paper to improve backwashing efficiency in an anaerobic sedimentation separation tank having improved sedimentation separation characteristics and a contact aeration tank. In addition, the present invention relates to a sewage treatment tank for controlling the concentration of activated sludge suspended matter to an appropriate amount for treatment.

[0002]

2. Description of the Related Art When a flush toilet is used on a site where a sewer for discharging sewage is not completely provided, sewage from the toilet is temporarily stored in a septic tank and then discharged to a general sewer. This septic tank is generally a sedimentation separation tank (anaerobic filter tank =
Decay tank), contact aeration tank (oxidation tank), settling tank,
It usually consists of a disinfection tank. In the case of a small number of people, an anaerobic filter bed tank using anaerobic bacteria may be provided instead of the sedimentation separation tank. The inflow water from the flush toilet first flows into a sedimentation separation tank (anaerobic filter bed tank), where suspended matter and solid matter are separated and separated, and decomposed by anaerobic bacteria. Next, it flows into the contact aeration tank, and organic matter in the sewage is ingested and oxidized by the aerobic bacteria in the biofilm and the suspended sludge formed on the surface of the filter medium. Therefore, a configuration is adopted in which outside air is directly sent from the inside of the tank.
Then, after the sedimentation in the sedimentation tank, the upper sewage is disinfected in the disinfection tank and discharged to the general sewer. In normal operation, air is continuously supplied to the contact aeration tank to supply dissolved enzymes and secure an appropriate water flow. In addition, since a biofilm is formed on the filter medium, backwashing is performed during maintenance and inspection to prevent the filter medium from being clogged, and the resulting sludge and the sediment sludge in the sedimentation tank are finally separated into a sedimentation separation tank (anaerobic filter bed). Tank). Note that this maintenance inspection is usually set at least once every three months and is performed by manual operation.

[0003]

In the conventional sedimentation separation tank (anaerobic filter bed tank), the components of the inflowing sewage are settled and separated according to the weight ratio, so that the heavy solids settle down. Light weight, such as toilet paper, floats upward and becomes scum (SCUM). The effluent flows out, but the scum accumulates at the top, which forms a layer and hardens. For example, when cleaning is performed about once every six months, the thickness of the scum becomes 50 cm or more.
It can reach as much as 2m. Therefore, unless the scum layer is crushed, the scum layer cannot be sucked out with the hose of the vacuum car, leading to an increase in the number of times of pumping and a deterioration in the purification function due to the scum content flowing out to the next tank. Also, in backwashing in a contact aeration tank and returning the sediment after backwashing, simply backwashing with air and returning it is inefficient, and even if returned, a considerable amount of excess sludge is still returned. There was a disadvantage that the concentration of the activated sludge suspended matter that adhered to the filter medium and had the most adverse effect on the purification function could not be maintained properly. In view of such circumstances, the present invention has been developed with the object of providing a septic tank that prevents stratification and outflow of scum and improves backwashing efficiency, and a purification system that controls the concentration of activated sludge suspended matter to an appropriate amount. It was done.

[0004]

Means for Solving the Problems The present invention has taken the following technical means in order to solve the above problems and achieve the object.

A. Automatic control in anaerobic sedimentation separation tank
An air supply pipe having an open / close valve is vertically provided, and the lower end of the air supply pipe is provided at the lower end of the air supply pipe.
An agitation mechanism provided with a plurality of nozzles is provided.
From the anaerobic sedimentation separation tank
A water purification tank that intermittently stirs the water surface and separates and sediments scum .

B. Automatic control in anaerobic sedimentation separation tank
An air supply pipe having an open / close valve is vertically provided, and the lower end of the air supply pipe is provided at the lower end of the air supply pipe.
The nozzle support tube is connected to the air supply tube and is rotatably mounted.
The nozzle support tube has multiple parts on both sides of the center of rotation.
A number of nozzles are arranged in the direction after the rotation, and
When the air is ejected intermittently, the nozzle
Rotates and intermittently agitates the wastewater in the anaerobic sedimentation separation tank.
Septic tank that.

C. Connected anaerobic sedimentation separation tank and contact aeration tank
In the sewage clarification tank, the anaerobic sedimentation separation tank,
An air supply pipe having an on-off valve that can be automatically controlled
A plurality of nozzles are arranged at the lower end of the pipe, and intermittent
To intermittently sewage anaerobic precipitation lees separation vessel by ejecting air
A stirring mechanism configured to stir the water
In the contact aeration tank, separate a plurality of backwash air pipes.
The nozzle support pipe is rotated at the lower end of each air supply pipe.
And the nozzle support tube has a plurality of
Nozzles are juxtaposed, and compressed air is alternately sent to each air supply pipe.
Control means, so that when each nozzle ejects
And a sewage purification tank that rotates the nozzle support tube .

[0008]

The present invention configured as described above has the following functions.

A. The inside of the anaerobic sedimentation separation tank is dark and calm in the conventional septic tank, and rot decomposition proceeds by anaerobic bacteria. The same applies to the present invention, however, since anaerobic bacteria dislike air oxidation, when air is sent from below for a certain period of time at regular intervals so as to minimize the effect on the oxidation, toilet paper is agitated. Because suspended matter such as is settled or cut by stirring,
Scum (SCUM) is prevented from agglomerating at the top of the tank.

B. When a plurality of air supply pipes in the contact aeration tank are arranged far apart, if the air supply is alternately controlled, for example, a compressed air flow is jetted from the right nozzle to reversely flow the sewage counterclockwise to filter. Since the biofilm (the layered clumps of aerobic bacteria) attached to the material is washed, clogging of the filter material by the biofilm is eliminated. When the airflow is ejected from the nozzle on the left side in turn, the sewage flows backward and hits the filter medium from the left side, so that the filter medium can be washed relatively appropriately. Separated sludge and excess sludge generated by backwashing are automatically returned to the sedimentation layer after settling for a certain period of time, so that the concentration of activated sludge suspended matter can be controlled to an appropriate amount and the purification function is always in the optimum state. Can be maintained.

C. When the backwash nozzle support pipe in the contact aeration tank is made rotatable and compressed air is sent from the air supply pipe, an air stream is blown out from the backwash nozzle, so the nozzle support pipe rotates by the reaction of the blow and the sewage is stirred. Therefore, a backflow is generated, and the washing of the filter medium can be made uniform.

[0012]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view of a sewage purification tank. In FIG. 1, a sewage purification layer 1 is composed of an anaerobic sedimentation separation tank (sedimentation separation, decay by anaerobic bacteria) 2, a sedimentation separation tank 3, a contact aeration tank (oxidation and filtration of various bacteria by aerobic bacteria) from the left side of the figure. 4) Second contact aeration tank 5, sedimentation tank 6, and disinfection tank 7. In the figure, reference numeral 1A denotes an inflow port into which sewage from a flush toilet flows, 1B denotes an outflow port through which purified sterile purified water flows out, and 1C denotes a lid on each tank. The anaerobic sedimentation separation tank 2
Inside, a stirring mechanism 8 is provided. The stirring mechanism 8
Is an air supply pipe 8A vertically extending from the air guide pipe 9 and a nozzle support pipe 8B mounted horizontally at the lower end of the air supply pipe 8A.
And a plurality of nozzles 8C mounted on the nozzle support tube 8B,
8C.. And an on-off valve 8D arranged at the base end of the air supply pipe 8A. The on-off valve 8D is composed of a solenoid valve,
It is electrically connected to an automatic controller outside the tank (not shown), and opens the valve every fixed time, and closes the valve as the fixed time elapses. The proximal end of the air guide tube 9 is connected to an air supply pump (not shown). The anaerobic sedimentation separation tank 2 configured as described above receives sewage discharged from the toilet directly, sediments and separates, is rotted by anaerobic bacteria, liquefies solids, and the liquid is transferred to the second sedimentation separation tank 3. The heavy solids settle down and the non-perishable scum floats upwards. Therefore, when the automatic controller controls the opening and closing of the on-off valve 8D intermittently, for example, once a day for one hour at night, the gas is sent through the air supply pipe 8A of the stirring mechanism 8. The compressed air blows out from the nozzles 8C and oscillates and stirs the sewage, so that the suspended matter is separated or the sediment settles. Therefore, problems such as coagulation, stratification and hardening of the scum do not occur. Since the stirring time is short and every long time,
It does not significantly affect the decay action of the anaerobic bacteria, but rather has the effect of mixing the newly flowing sewage on average to stir the sewage up and down so that the decay action is performed on average.

The stirring mechanism 8 is not limited to this embodiment, and the design can be changed as appropriate.
For example, the on-off valve 8D can be a manual type or a combination of manual and automatic. Also, a nozzle support tube 12 described later.
Can be made rotatable.

Next, sewage discharged from the discharge port 3A of the second settling / separation tank 3 flows into the contact aeration tank 4 in FIG. 1 onto a lower filter medium (not shown). As a result, a biofilm (also referred to as a filter membrane) formed by aerobic bacteria is formed on the surface of the filter medium, and various bacteria and organic substances in the wastewater are taken up and decomposed by the aerobic bacteria. Therefore tank 4
An air diffuser 4B for sending fresh air to the biofilm is provided from the lower part of the air supply pipe, and an air supply pipe 4A connected to the air guide pipe 9 penetrates the inside thereof. Reference numeral 4C is an on-off valve. The Figure 1, reference numeral 10 denotes a return pipe, the distal end is open at anaerobic precipitated fraction Hanareso 2, in contact aeration tank 5 and settling tank 6, the suction pipe 11, 11 to return pipe 10 It is hanging. Thus, in each of the suction pipes 11, there are air supply pipes 11 </ b> A,
A are penetrated to the lower part, and when the compressed air which is pressure-fed through the air guide pipe 9 is blown out from the lower end of the air feed pipe 11A, the bubbles rise up the suction pipe 11 vigorously. , 6 can be sucked up and returned to the anaerobic sedimentation separation tank 2 via the return pipe 10.

In FIG. 1, a plurality of (two in the figure) air supply pipes 12 are vertically provided at intervals from the air guide pipe 9 in the contact aeration tank 4. Horizontally long nozzle support tubes 12A, 12A are attached to lower ends of the air supply tubes 12, 12, respectively.
A plurality of backwash nozzles 1 are provided in the nozzle support tubes 12A, 12A.
12B are disposed so as to be opposed to each other between the two support tubes 12A. In addition, each air pipe 12,1
Opening / closing valves 12C, 12C, which are electromagnetic valves, are disposed at the base end of 2 and are set so as to be alternately opened and closed at regular intervals by the automatic controller outside the tank. That is, for the first 15 minutes, the left open / close valve 12C opens, then the left open / close valve and the right open / close valve 12C open for 15 minutes, and the cycle is repeated. Since the biofilm is generated from the lower right to the upper left, the purification function can be improved by appropriately and uniformly adjusting the adhesion of the biofilm on the surface of the filter medium. The same applies to the second contact aeration tank 5.

FIG. 2 is an automatic maintenance system flow relating to the opening and closing operation of each on-off valve of each tank in FIG. First, steady operation is performed by opening and closing valves 4C and 4C of a contact aeration tank (in FIG. 2, simply abbreviated as 4 tanks and 5 tanks).
Open for hours and automatically close for 1 hour. The on-off valve 8D of the sedimentation agitation tank (referred to as two tanks) is opened once an day for one hour when the on-off valves 4C, 4C are closed during the night, and is automatically closed. Next, automatic maintenance should be performed at least once a month or two months.
Is opened for 15 minutes to reverse the flow of sewage, and after automatic valve opening,
The open / close valve 12C at the right of the four tanks is opened to reverse the wastewater, and the biofilm washing of the tank 4 is completed. Next, also in the five tanks, the left and right on-off valves 12C, 12C are similarly opened and closed every 15 minutes. After this, the open / close valves 11A of the four tanks are opened for 15 minutes,
The sediment is returned to the anaerobic sedimentation / separation tank 2, and then the on-off valves 11A of the five tanks are opened for 15 minutes to return the sediment to the anaerobic sedimentation / separation tank 2. Next, when the on-off valves 11A of the six tanks are opened for 15 minutes to return the sediment of the sedimentary layer 6 to the anaerobic sedimentation separation tank 2, the automatic maintenance system ends. The automatic control of each of these on-off valves is performed by storing and setting in an automatic controller.

FIG. 3 is a plan view showing a second embodiment in which the nozzle support pipes 12A of the backwash nozzles 12B are rotatable. That is, the nozzle support pipe 12A is rotatably connected to the lower end of the air supply pipe 12 via the seal coupling 12D. On the side surface of the nozzle support tube 12A, backwash nozzles 12B are disposed on the left and right sides of the air supply tube 12 in opposite directions. Accordingly, when air is ejected from the backwash nozzles 12B, the nozzle support tube 12A rotates about the coupling 12D as shown by the arrow in FIG. The membrane can be washed. If the nozzle support tube 12A is in the form of a propeller, water can flow well upward, and can be formed in a plurality of stages or only on one side.

[0018]

The present invention configured as described above has the following excellent effects.

A. Anaerobic decay by anaerobic bacteria
The precipitation separation tank, by disposing the stirring mechanism, only constantly first constant time, because especially to be able to stir the upper portion, prior to solve the difficulties scum had leaked to the stratified cured or next tank Also, scum can be putrefactive.

B. Always Automatic control the stirring mechanism 1
In a system that can be operated for only one fixed time at regular intervals, no manual labor is required, and the original performance of the septic tank can be fully utilized.

C. In the case where two backwash nozzles are installed in the contact aeration tank, one backwash nozzle is always used.
Backwashing fumes can be emitted alternately and in different directions for a fixed period of time , so that a uniform backwashing water flow can be given to the entire area of the filter medium to achieve desired biofilm adjustment. In addition, since it is returned after backwashing and sedimentation by automatic control, the concentration of the activated sludge suspended matter in the contact aeration tank can be controlled to an appropriate amount.

D. When the backwash nozzle support pipe in the contact aeration tank is made rotatable horizontally in the lower part of the air supply pipe, the sewage is agitated because the nozzle support pipe and the nozzle rotate with the force of blowing air from the nozzle. As a result, a good backwash effect and uniform air feeding can be achieved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a sewage purification tank.

FIG. 2 is an automatic maintenance system flow.

FIG. 3 is a plan view showing an embodiment in which a support pipe of a backwash nozzle is rotatable.

[Explanation of symbols]

Reference Signs List 1 sewage purification tank 2 anaerobic sedimentation separation tank 3 sedimentation separation tank 4, 5 contact aeration tank 4A air supply pipe 4B diffuser pipe 4C open / close valve 6 sedimentation tank 7 disinfection tank 8 stirring mechanism 8A air supply pipe 8B nozzle support pipe 8C nozzle 8D open / close valve 9 Air guide pipe 10 Return pipe 11 Suction pipe 11A Air supply pipe 11B, 12C Open / close valve 12 Air supply pipe 12A Nozzle support pipe 12B Backwash nozzle 12C Open / close valve

Claims (3)

(57) [Claims] An anaerobic sedimentation separation tank and a contact aeration tank are connected in series.
In the septic tank, stirring mechanism into the anaerobic sedimentation separation tank
And the stirring mechanism can be automatically controlled by a vertically installed air supply pipe.
On-off valve is provided, and a plurality of nozzles are arranged at the lower end of the air supply pipe.
And pressurizedly eject compressed air from the nozzle at all times.
Intermittently blowing up sewage in the anaerobic sedimentation separation tank from below
A sewage purification tank characterized in that a skull is separated and settled by agitating a surface layer portion of the sewage. 2. An anaerobic sedimentation separation tank and a contact aeration tank are connected.
And the septic tank, in contact aeration tank, automatic control
A plurality of air supply pipes having on-off valves capable of
The nozzle support pipe communicates with the air supply pipe at the lower end of the
Mounted on the nozzle support tube on both sides of the center of rotation
Arrange multiple nozzles in the direction after the rotation, and
The air supply pipe is provided with control means for alternately sending compressed air, and
When the air is intermittently ejected from the squid
The nozzle support tube rotates due to the reaction, and the wastewater in the contact aeration tank
A sewage treatment tank characterized by intermittently generating a vortex bubble flow and stirring and treating the mixture . 3. consecutively provided a contact aeration tank and anaerobic sedimentation separation tank
In the wastewater purification tank, the anaerobic sedimentation separation tank was stirred.
A stirring mechanism is provided, and the stirring mechanism automatically controls the vertically installed air pipe.
A controllable on-off valve is provided, and a plurality of
Air from the nozzle constantly and intermittently.
So that the wastewater in the anaerobic sedimentation separation tank is intermittently stirred.
And a backwashing air supply pipe is provided in the contact aeration tank.
A plurality of nozzles are vertically separated and nozzle support is provided at the lower end of each air supply pipe.
The tube is rotatably mounted, and the nozzle support tube
Multiple nozzles are arranged side by side, and compressed air is
A control means for sending air alternately is provided,
A sewage treatment tank characterized in that a nozzle support pipe is rotated by a fume to perform treatment .