JPH054094A - Batch type activated sludge treatment equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a batch type activated sludge device capable of performing efficient treatment by performing intermittent aeration by reducing the number of times of starting and stopping operations of an air blower and a sewage inflow pump. [Structure] In a batch type activated sludge treatment device in which a sewage inflow / agitation process, aeration / agitation process, and discharge process are sequentially performed in a single treatment tank by time control, the treatment tank uses a partition wall 6 having an opening. It is divided into two tanks 1A and 1B, the main pipe of the air blower is branched and connected to each tank, and the opening / closing valves 8A and 8 are provided above the branch pipes 5A and 5B.
B, a submersible batch system characterized in that submersible stirrers 4A and 4B are provided in the lower part, the lower part of the on-off valve is connected to a sewage inflow pipe, and check valves 9A and 9B are provided in the sewage inflow pipe. It is an activated sludge treatment device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a batch type treatment apparatus using an activated sludge method for organic sewage, and more particularly to discharging treated water after biologically treating the sewage in a single tank. It relates to a batch type activated sludge treatment device.

[0002]

2. Description of the Related Art A batch type activated sludge treatment method is a method in which an inflow / agitation step of stirring while inflowing sewage into a single tank and an aeration step of intermittent aeration are repeated at preset times,
It is composed of a treatment step in which a precipitation step and a step of discharging treated water which is supernatant water are one cycle. In addition, each process
It is a method of removing BOD, nitrogen and phosphorus in wastewater by intermittent aeration, which is operated at a preset time.

However, the operation of the sewage inflow pump in the stirring process and the intermittent aeration operation in the aeration process are started and started by the air blower.
When the stop operation is performed, the overcurrent protection circuit is frequently activated and mechanical wear and damage are likely to occur. Also, in order to reduce the number of times of operation, when an electromagnetic valve or an air operated valve is provided, at least four valves are required, which is complicated and there is a problem in management.

[0004]

The present invention reduces the load on the air blower and the sewage inflow pump by using the open / close valve having a simple structure even when the number of times of intermittent aeration is large, and the waste water can be treated in An object of the present invention is to provide a batch type activated sludge treatment device capable of efficiently removing BOD, nitrogen and phosphorus.

[0005]

According to the present invention, a main pipe of an air blower is branched, and a sewage inflow pump and an underwater agitator are connected to the branch pipe, and aeration and sewage inflow are alternately performed by a valve. When the aeration is performed in the tank, the other tank is configured to allow the inflow of sewage to achieve the above object.

That is, according to the present invention, in the batch type activated sludge treatment device in which the inflow / agitation step of a wastewater, the aeration / agitation step and the discharge step are sequentially performed in a single treatment tank by time control, the treatment tank has an opening. It is divided into two tanks by a partition wall having an air blower, and the main pipe of the air blower is branched and connected to each tank. An opening / closing valve is provided at the upper part of each branch pipe and an underwater agitator is provided at the lower part of the opening / closing valve. The present invention provides a batch type activated sludge treatment device, characterized in that it is connected to a sewage inflow pipe in the lower part of the above and a check valve is provided in the sewage inflow pipe.

In the treatment apparatus of the present invention, the treated water discharge apparatus is not particularly limited and various kinds can be applied. However, the treated water discharge apparatus with a float is used, and the float and the main pipe of the air blower are used. Is connected via an open / close valve, the air from the air blower can be effectively used to efficiently discharge the supernatant water.

[0008]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a treatment apparatus showing an embodiment of the present invention, FIG. 2 is an illustration of steps, and FIG. 3 is an illustration of a treated water discharge apparatus used in the treatment apparatus shown in FIG. .

In FIG. 1, the treatment apparatus is composed of a single tank, but is divided into a first tank 1A and a second tank 1B by a partition wall 6 and a baffle wall 7, and a sewage inflow pump 2 and an air blower 3 are provided.
Is connected to each tank by branch pipes 5A and 5B, and submersible stirrers 4A and 4B are installed below the branch pipes 5A and 5B. In the partition wall 6 and the baffle wall 7,
Openings 6A and 7A are provided respectively, and these tanks communicate with each other. Further, a surplus sludge extraction pump 10 is connected to the first tank, and a treated water discharge device 11 is installed in the second tank. The sewage inflow pipe discharged from the sewage inflow pump is branched in order to inject the sewage into the first tanks 1A and 1B, respectively, and is connected to the branch pipes 5A and 5B via the check valves 9A and 9B, respectively. On-off valves 8A and 8B are provided above the pipe. Further, the treated water discharger 11 is connected to the main pipe of the air blower 3 via the open / close valve 8C. Each device is operated by time control.

When sewage treatment is performed using the apparatus of the present invention, as shown in FIG. 2, first, the aeration step, the stirring step and the sewage inflow step are started, and the sewage inflow pump 2 and the air blower 3 are started. In addition, by driving the submersible stirrers 4A and 4B, electrically opening and closing the on-off valve 8A, and electrically closing the on-off valve 8B, sewage is automatically checked by a check valve 9B having a small wind pressure.
Through the underwater agitator 4B. Also, the air is
It flows into the submersible stirrer 4A via the on-off valve 8A. In addition,
In FIG. 2, the chain line indicates intermittent operation, and actual battle means continuous operation.

As described above, the sewage flows into the check valve side tank where the wind pressure is not applied, while the air flows into the check valve side tank where the wind pressure is applied. Therefore, when the opening and closing valves are alternately opened at preset times, intermittent aeration is performed in both tanks, and it is not necessary to frequently shut off the air blower and the dirty water inflow pump. Moreover, since the wastewater always flows into the tank side with less oxygen, the BOD source of the wastewater can be used,
The denitrification reaction is easily performed. Efficient contact and mixing can be performed by constantly rotating the submerged agitator during the intermittent aeration process and the sewage inflow process. In this way, BOD, nitrogen and phosphorus in the wastewater are biologically removed by alternately opening and closing the open / close valves 8A and 8B at preset times.

After a certain period of time has passed, the sewage inflow pump 2, the air blower 3, and the submersible stirrers 4A and 4B are stopped to start the precipitation step. Next, in the discharge step, the treated water discharge device 1 is opened by opening the electrically operated on-off valve 8D.
Treated water is discharged from 1. As shown in FIG. 3, the treated water discharger 11 has a structure in which a bellows portion 14 and a float 15 are coupled to a water intake portion 13 having an opening 12 portion, and the float 15 includes a tube 16 and an on-off valve 8C. It is connected to the main pipe of the air blower 3 via. Therefore, when the opening / closing valves 8C and 8D are opened as described above, the air in the float 15 is discharged through the tube 16 and the opening / closing valves 8C and 8D, the float 15 sinks, and the intake part also sinks at the same time, and the treated water opens. It flows in from the portion 12, enters the bellows portion 14, and is discharged through the pipe.

After a predetermined time, when air is introduced into the float 15 by operating the air blower 3 and opening the open / close valve 8C and closing the open / close valve 8D, the float 15 and the water intake part 13 are above the liquid level. And the inflow of treated water from the opening 12 is stopped. Next, the on-off valve 8
When C is closed, one cycle ends and the process returns to the first step. The surplus sludge is regularly withdrawn by the surplus sludge pump 10.

In the above embodiment, the branch pipes are provided with the on-off valves 8A and 8B and the waste water inflow pipes are provided with the check valves 9A and 9B. Instead of these, the connection between the waste water inflow pipe and the branch pipes is shown. It is also possible to adopt a structure in which a three-way on-off valve is provided in the section.

Example 1 Using the apparatus shown in FIG. 1, sewage having the water quality shown in Table 1 was treated as sewage under the operating conditions shown in Table 1, and the water quality of the obtained treated water is shown in Table 1. Aeration was performed by continuous aeration in the conventional method, and in the method of the present invention, the on-off valve 8A and the on-off valve 8B were electrically opened and closed alternately at intervals of 10 minutes.

[0016]

[Table 1]

[0017]

When the apparatus of the present invention is used for aeration in one tank, stirring and inflow of sewage are performed in the other tank without performing aeration, so a combination of anaerobic treatment and aerobic treatment is performed. It is possible to perform not only BOD removal but also nitrification and denitrification, and further dephosphorization efficiently, and it is possible to expect bulking prevention and scum generation prevention. Furthermore, since the number of times the sewage inflow pump and the air blower are started and stopped is small and all the work can be performed electrically with time control together with opening and closing of the on-off valve, the management of the device is easy. Therefore, it can be effectively used as a device that can be easily managed especially in a depopulated area or a small-scale sewer.

[Brief description of drawings]

FIG. 1 is a sectional view of an activated sludge treatment device for wastewater showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an activated sludge treatment process of wastewater using the device of the present invention.

FIG. 3 is an explanatory view of the treated water discharge device shown in FIG. 1.

[Explanation of symbols]

1A first tank 1B second tank 2 Sewage inflow pump 3 air blower 4A and 4B underwater stirrer 5A and 5B branch piping 6 partition walls 7 Barrier wall 8A, 8B, 8C and 8D open / close valve 9A and 9B check valve 11 Treated water discharge device

Claims (3)

[Claims] 1. A partition wall in which a treatment tank has an opening in a batch type activated sludge treatment device in which the inflow / agitation step of a wastewater, the aeration / agitation step and the discharge step are sequentially performed in a single treatment tank by time control. It is divided into two tanks, and the main pipe of the air blower is branched and connected to each tank. An on-off valve is provided at the upper part of each branch pipe and an underwater stirrer is provided at the lower part of the branch pipe. A batch type activated sludge treatment device for sewage, which is connected to a sewage inflow pipe and is provided with a check valve in the sewage inflow pipe. 2. The batch type of sewage according to claim 1, wherein a three-way on-off valve is provided at the connection between the sewage inflow pipe and the branch pipe, instead of the check valve of the sewage inflow pipe and the opening / closing valve on the upper part of the branch pipe. Activated sludge treatment equipment. 3. The batch type activated sludge treatment device of sewage according to claim 1 or 2, wherein the main pipe of the air blower and the float of the treated water discharge device with float are connected via an on-off valve.