JPH04367793A - Flow adjustment of purification tank - Google Patents

Abstract

PURPOSE:To prevent a large amount of inflow water from inflicting an impact to a contact aeration tank due to the displacement of a water current by arranging a quantitative discharge pump in a current transfer pipe from the second chamber of an aerophobic filtration bed to the contact aerophobic tank, then isolating a filtration medium from the current transfer pipe and causing a treated water to flow downward from the filtration medium to adjust the flow between the second chamber of the aerophobic filtration bed tank and the contact aeration tank. CONSTITUTION:An aerophobic filtration bed tank or a sedimentation segregation tank, an aeration tank 40, a sedimentation tank 50 and a sterilization tank 60 are arranged sequentially. Then the aerophobic filtration bed chamber or the sedimentation segregation tank is divided into the first chamber 20 and the second chamber 30. Further, a flow adjustment pump 36 for transferring a treated water from the second chamber 30 to the aeration tank 40 is provided in a current transfer pipe 3 from the second chamber 30 to the contact aeration tank 40. The treated water entering the current transfer pipe 34 after passing through a filtration medium 32 in a state of downward current from the second chamber 30, is transferred to the aeration tank 40 by operation of the pump 36. Subsequently, the possible adverse effects of a large amount of inflow water upon the aeration tank in a purification tank is absorbed by the water level variation of the aerophobic filtration bed tank. Thus the purification is free from the turbulence of the treated water flowing out of the aerophobic filtration bed tank by a large amount of inflow water.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a septic tank without a flow rate adjustment function, and particularly to a small combined septic tank for domestic use.

0002

BACKGROUND OF THE INVENTION Conventional septic tanks without a flow rate adjustment function are often adversely affected by a large amount of inflow water. In particular, in an anaerobic filter bed tank, sludge flows into the next contact aeration tank. That is, as shown in FIG. 3, an anaerobic filter bed tank first chamber (or sedimentation separation tank) 20, an anaerobic filter bed tank second chamber 30, a contact aeration tank 40, a sedimentation tank 50, and a disinfection tank 60 are arranged in series. In a septic tank configured by ), the sludge from the second chamber of the anaerobic filter bed tank may enter the flow to the contact aeration tank 40 (arrow A). The sludge that has entered the contact aeration tank 40 affects the aeration process by the aeration device 44, and deteriorates the quality of the outflow water (arrow B) coming out of the disinfection tank 60.

[0003] Therefore, in conventional septic tanks, it has been considered to use a part of the sedimentation separation tank or contact aeration tank as a flow rate adjustment section to adjust the flow rate (for example, see Japanese Patent Publication No. 58-39836). ).

0004

[Problems to be Solved by the Invention] Furthermore, as a method for adjusting the flow rate of a septic tank without a flow rate adjustment function, there is a method that utilizes water level fluctuations in an anaerobic filter bed tank.

[0005] As an adjustment method based on water level fluctuations, without providing an advection pipe from the second chamber 30 of the anaerobic filter bed tank to the contact aeration tank 40, a fixed amount is sent to the contact aeration tank 40 in small amounts as shown in FIG. Attach the pump 36 to the anaerobic filter bed tank second chamber 30
There is a method of varying the water level. In this case, the treated water leaving the anaerobic filter bed tank first chamber 20 descends through the advection pipe 30a,
It passes through the filter medium 32 in an upward flow. And metering pump 3
6, the treated water in the second chamber 30 of the anaerobic filter bed tank is
Inflow water (arrow C) and flow rate to contact aeration tank 40 (arrow A)
Therefore, the water level fluctuates between the highest water level HWL and the lowest water level LWL. However, in this system, the metering pump 36 is disposed above the filter medium 32, and the flow of water in the second chamber 30 of the anaerobic filter bed tank is an upward flow. Water level fluctuation in the second tank chamber 30, that is, the lowest water level LWL
The function of the second chamber 30 of the anaerobic filter bed tank is not stable as it is directly affected by the amount of water from HWL to the highest water level HWL.

[0006] The present invention absorbs the adverse effects that a large amount of inflow water to the septic tank may have on the contact aeration tank by changing the water level of the anaerobic filter bed tank, and uses the large amount of inflow water to absorb the treated water coming out of the anaerobic filter bed tank. The purpose is to provide an undisturbed septic tank.

[0007]

[Means for Solving the Problems] In order to achieve the above object, in the septic tank of the present invention, a metering pump is provided in the advection pipe to the contact aeration tank in the second chamber of the anaerobic filter bed tank, and the anaerobic filter bed tank The flow of water in the filter medium of the second chamber was made downward.

That is, in the method of the present invention, an anaerobic filter bed tank first chamber (or sedimentation separation tank), an anaerobic filter bed tank second chamber, a contact aeration tank, a settling tank, and a disinfection tank are arranged in sequence. In an operating method in which the flow rate of a small domestic combined septic tank is adjusted by changing the water level of the anaerobic filter bed tank, the flow rate adjustment pump that transfers treated water from the second chamber of the anaerobic filter bed tank to the contact aeration tank is connected to the anaerobic filter bed tank. Provided in the advection pipe from the second chamber to the contact aeration tank,
The flow rate adjustment pump is operated according to the inflow water.

In the present invention, the water level in the anaerobic filter tank is varied by sending the treated water in small amounts to the contact aeration tank using a metering pump installed inside the advection pipe in the second chamber of the anaerobic filter tank. is isolated from the filter medium, and the flow of water in the filter medium in the second chamber of the anaerobic filter bed tank is made downward. This results in
The treatment in the second chamber of the anaerobic filter bed tank is affected only by the amount of water flowing in from the lowest water level to the highest water level of the advection pipe, and is not affected by the operation of the metering pump.

0010

[Operation] When wastewater is treated in the septic tank configured as described above, a flow rate adjustment pump is installed in the advection pipe of the second chamber of the anaerobic filter tank, so a large capacity can be transferred to the first chamber of the anaerobic filter tank in a short period of time. Even if sewage flows in, it can be stored up to HWL in the anaerobic filter bed tank, and the discharge to the contact aeration tank can be maintained at a fixed amount using the flow rate adjustment pump. Therefore, the precipitation separation process can be kept stable with only slight fluctuations in the water level between HWL and LWL in the advection tube.

[0011] The present invention uses a metering pump installed inside the advection pipe of the anaerobic filter bed tank to cause the anaerobic filter tank treated water to flow into the contact aeration tank in a fixed amount at a time, so that the anaerobic filter bed tank is controlled by the action of the pump. After a certain amount of time, the water level will drop. Since the water level in the anaerobic filter bed tank is lowered, even if a large amount of wastewater flows in, the water level in the anaerobic filter bed tank will only rise, and the contact aeration tank will not be adversely affected.

Furthermore, by separating the filter medium of the anaerobic filter bed tank from the advection pipe to the contact aeration tank and making the water flow in the filter medium downward, the influence of inflow water on the anaerobic filter bed tank can be reduced. The amount of water falls within the range from the lowest water level to the highest water level in the advection pipe of the anaerobic filter tank, and is not significantly affected by inflow water or the associated operation of the pump in the advection pipe, so the second anaerobic filter bed tank
The function of the room becomes stable.

[0013]

[Embodiment] An embodiment in which the present invention is applied to a household combined treatment tank will be described with reference to the drawings.

FIGS. 1 and 2 are conceptual diagrams showing an embodiment in which the present invention is applied to a combined septic tank for one household.

The septic tank is composed of an anaerobic filter bed tank first chamber 20, an anaerobic filter bed tank second chamber 30, a contact aeration tank 40, a settling tank 50, and a disinfection tank 60. Anaerobic filter bed tank first chamber 20 and second chamber
The treatment in the chamber 30 is called primary treatment, and the contact aeration tank 40
, the processing in the settling tank 50 and the disinfection tank 60 is called secondary processing. In the present invention, a flow rate adjustment pump 36 is provided between the primary treatment and the secondary treatment. Sewage flowing in from the inlet 21 (arrow C) flows into the anaerobic filter bed tank first chamber 20, flows down through the filter medium 22, is subjected to sedimentation separation treatment, and is transferred to the advection tube 2.
4, from the communication port 28 to the second chamber 30 of the anaerobic filter bed tank, flows down through the filter medium 32, passes through the advection pipe 34, and enters the contact aeration tank 40 from the metering pump transfer pipe 38.

The metering pump transfer pipe 38 is located higher than the HWL, and the metering pump 36 in the advection pipe 34 causes the treated water to enter the contact aeration tank 40 from the second chamber 30 of the anaerobic filter bed tank.

[0017] The metering discharge pump 36 is
93 can be used.

Since this metering pump has no moving parts, it is suitable for use as an advection device for purification treatment, and is excellent as a transfer pump with a minute flow rate that is equalized on the average.Furthermore, suspended solids are removed in an anaerobic filter bed tank. Therefore, it is safe for application.

In the contact aeration tank 40, the treated water is purified by the biofilm grown on the contact material 42, and is also aerated by the aeration device 44. That is, blower 45
The air sent through the air supply pipe 44a of the aeration device 44 comes out from the aeration pipe 44b and aerates the treated water.

The treated water subjected to contact aeration is transferred to a contact aeration tank 40.
It enters the settling tank 50 through the communication port 46 at the bottom of the tank. The thickened sludge adhering to the contact material 42 is separated by the flow of treated water and becomes suspended solids (SS), but it settles as separated sludge and is stored. The supernatant liquid in the settling tank 50 enters the disinfection tank 60. Disinfected treated water is discharged from here (arrow B).

An example of the operation of the septic tank of this embodiment will be explained.

The amount of sewage flowing into the first chamber 20 of the anaerobic filter bed tank is determined when the treated water enters the second chamber 30 of the anaerobic filter bed tank from the first chamber 20 of the anaerobic filter bed tank through the communication port 28, and is quantified. pump 36
The water is sent from the second chamber 30 of the anaerobic filter bed tank to the contact aeration tank 40. From the contact aeration tank 40, it enters the settling tank 50, passes through the disinfection tank 60, and is discharged. In addition, since the bottom of the settling tank 50 and the contact aeration tank 40 are in communication, there is a flow from the settling tank 50 to the contact aeration tank 4.
The sludge is returned to 0 and stored in the contact aeration tank.

In this embodiment, the water level fluctuates between HWL and LWL depending on the difference between the amount of water transferred by the metering pump 36 and the amount of inflow water.

In the septic tank of this embodiment, since the metering pump 36 is installed in the advection pipe 34 of the second chamber 30 of the anaerobic filter bed tank, even if a large amount of wastewater flows in for a short period of time, it is not possible to transfer the wastewater to the anaerobic filter bed tank. It can be absorbed in the first chamber 20 and the second chamber 30, and the discharge to the contact aeration tank 40 can be maintained at a fixed amount. In the second chamber 30 of the anaerobic filter bed tank, the water level rises only slightly, and the contact aeration tank 40
Sludge will not be mixed into the inflow water. In this way, the adverse effects of a large amount of water flowing into the septic tank in a short period of time are absorbed by the water level fluctuations in the anaerobic filter bed, and the second anaerobic filter bed
By isolating the flow of water in the filter medium of the chamber from the advection pipe and causing it to flow downward, the second chamber of the anaerobic filter bed tank is not disturbed by large amounts of inflow water or the associated pump operations.

[0025]

[Effects of the Invention] Since the present invention is constructed as described above, it produces the following effects.

When adjusting the flow rate of a small domestic septic tank by changing the water level of the anaerobic filter tank, a metering pump is installed inside the advection pipe of the second chamber of the anaerobic filter tank to send small flow rates to the contact aeration tank. The effect of water flowing into the septic tank is absorbed by varying the water level in the floor tank. By making the flow of water in the filter medium in the second chamber of the anaerobic filter bed tank downward, the second chamber of the anaerobic filter bed tank is only affected by the amount of water from the lowest water level to the highest water level of the advection pipe. . Furthermore, by using a metering pump to advect sewage from the anaerobic filter bed tank to the contact aeration tank, it is possible to prevent sludge from flowing out to the contact aeration tank next to the anaerobic filter bed tank.

[Brief explanation of drawings]

FIG. 1 is a schematic side sectional view showing a septic tank to which an embodiment of the present invention is applied.

FIG. 2 is a schematic plan view of the septic tank in FIG. 1.

FIG. 3 is a side sectional view showing an example of a conventional septic tank.

FIG. 4 is a side sectional view showing an example of flow rate adjustment in a conventional septic tank.

[Explanation of symbols]

20 Anaerobic filter bed tank 1st room 21 Inlet 22 Filter medium 24 Advection tube 28 Communication port 30 Anaerobic filter bed tank 2nd chamber 34 Advection tube 36 Metering pump 38 Metering pump transfer pipe 40 Contact aeration tank 42 Contact material 44 Air diffuser 44a Air pipe 44b Diffuser pipe 46 Communication port 50 Sedimentation tank 60 Disinfection tank

Claims (1)

[Claims] Claim 1. A method for operating a septic tank having an anaerobic filter bed tank or a sedimentation separation tank, an aeration tank, a sedimentation tank, and a disinfection tank arranged in sequence, wherein the anaerobic filter bed tank or the sedimentation separation tank is located in a first chamber. and a second chamber, and a flow rate adjustment pump for transferring the treated water from the second chamber to the aeration tank is installed in the advection pipe from the second chamber to the contact aeration tank, so that the treated water in the second chamber flows downward into the filter medium. A method of operating a septic tank in which treated water that enters an advection pipe after passing through is transferred to an aeration tank by operating a flow rate adjustment pump.