JP3069052B2 - Supernatant drainage device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for discharging supernatant water.

[0002]

2. Description of the Related Art Conventionally, wastewater, that is, water to be treated is intermittently supplied to a treatment tank, biological treatment is performed by activated sludge in the treatment tank, and supernatant water is discharged from the treatment tank. A batch activated sludge process is provided. In this case, when exposure (aeration) and agitation (stirring) are performed in the treatment tank, microorganisms in the activated sludge decompose organic matter in the water to be treated into carbon dioxide gas and water, and the microorganisms themselves proliferate. Subsequently, when the aeration and the stirring are stopped, the activated sludge in the water to be treated precipitates (dends), and supernatant water can be obtained above the treatment tank.

[0003] When biological treatment is performed using activated sludge in a treatment tank, scum is generated and mixed into the supernatant water. Therefore, a scum baffle is provided at the outlet of the supernatant water, or water is sprayed on the water surface near the outlet to prevent the scum from being discharged together with the supernatant water.

FIG. 2 is a process diagram of a conventional batch activated sludge method. Step S1 In the inflow step, the water to be treated is caused to flow into the treatment tank. Activated sludge for performing biological treatment is accommodated in the treatment tank. Step S2 In the aeration and stirring step, air is supplied to the treatment tank by a blower or the like, and the air is injected into the water to be treated via a nozzle or the like, and aeration and stirring are performed. As a result, the microorganisms in the activated sludge decompose organic matter in the water to be treated into carbon dioxide and water, and the microorganisms themselves proliferate. Step S3 When the aeration and stirring are stopped, in the precipitation step, the activated sludge descends and precipitates in the treatment tank, and supernatant water is obtained above the treatment tank. In step S4, in order to prevent the scum from being mixed into the supernatant water and discharging the scum together with the supernatant water from the outlet of the supernatant water, water is sprayed on the water surface near the outlet of the supernatant water in the watering step. Step S5 In the supernatant water discharging step, the supernatant water is discharged from the treatment tank.

[0005]

However, in the above-described conventional supernatant water discharging apparatus, scum remains in the processing tank, so that it is necessary to discharge the scum from the processing tank by a vacuum device or the like. Therefore, not only does the operation of the vacuum device or the like become troublesome, but also the cost of wastewater treatment increases.

[0006] The present invention solves the problems of the above-mentioned conventional supernatant water discharge apparatus, and provides a supernatant water discharge apparatus which can reduce the cost of wastewater treatment without leaving scum in the treatment tank. The purpose is to do.

[0007]

For this purpose, the apparatus for discharging supernatant water according to the present invention has a discharge unit movably arranged vertically and a drive means for moving the discharge unit vertically. The discharge unit has an open upper portion, a scum discharge tank to which a discharge pipe for discharging scum is connected, and is disposed to be vertically movable with respect to the scum discharge tank. A supernatant water discharge tank to which a discharge pipe for discharging is connected, a float chamber integrally formed with the supernatant water discharge tank, a lower part being opened, and an upper wall forming a closed space, and air in the float chamber being formed. An opening / closing means for selectively discharging is provided.

In another supernatant water discharging apparatus of the present invention,
Furthermore, it has a control device. Then, the control device closes the opening / closing means in the scum discharging step, generates buoyancy by the float chamber, moves the supernatant water discharging tank upward with respect to the scum discharging tank, and in the supernatant water discharging step, The opening / closing means is opened to eliminate the buoyancy of the float chamber, and the supernatant water discharge tank is moved downward with respect to the scum discharge tank.

In still another apparatus for discharging supernatant water of the present invention, each of the discharge pipes is connected to a common discharge pipe for discharging scum and supernatant water, and the common discharge pipe discharges scum. And a scum discharge line for discharging the supernatant water.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view of a discharge unit according to the first embodiment of the present invention.
FIG. 5 is a front view of a supernatant water discharge device according to the first embodiment of the present invention, FIG. 5 is a side view of the supernatant water discharge device according to the first embodiment of the present invention, and FIG. 6 is a first embodiment of the present invention. FIG. 7 is a plan view of a supernatant water discharging device according to a first embodiment of the present invention.
It is a support state figure of the discharge unit in embodiment.

In FIG. 1, reference numeral 11 denotes a processing tank, 12 denotes a frame fixed to a side wall (not shown) of the processing tank 11, and 13 denotes a work table installed on an upper end of the frame 12. The work table 13 has a pair of support members 14, and the support member 1
4, one inverter motor 15 as a driving means is provided. The inverter motor 15 and a pair of stainless steel spindles 17 are connected via a gear box 16, and each of the spindle motors 1 is driven by driving the inverter motor 15 by a control device (not shown).
7 can be rotated in the forward and reverse directions. When the spindle 17 is rotated in the forward direction and the reverse direction, the discharge unit 30 connected via the spherical journal 18 below the spindle 17 is moved up and down at a constant speed, and the discharge unit 30 set at the uppermost position is set. 1
A position A, a second position B set at the middle, and a third position C set at the lowest position are taken. Incidentally, 19 is connected between each gearbox 16, a transmission shaft for transmitting the rotation of the inverter motor 15, W _H is the maximum water level when the water to be treated was allowed to flow into the treatment tank 11, W _L upper supernatant water Is the lowest surface of the water to be treated after is discharged.

The discharge unit 30 has, in the center, a supernatant water discharge tank 31 for discharging the supernatant water above the processing tank 11, and a processing tank 1 on both sides of the supernatant water discharge tank 31.
1 has scum discharge tanks 32 and 33 for discharging scum (not shown) floating on the water surface, and a float chamber 34 for giving buoyancy to the supernatant water discharge tank 31 below the supernatant water discharge tank 31, respectively. The supernatant water discharge tank 31 and the float chamber 34 are integrally formed. The float chamber 34 is formed of an inverted box-like body whose upper wall is closed and whose lower part is open. The discharge unit 30 includes a relief pipe 55 connected to the upper wall of the float chamber 34 and an opening / closing means disposed on the relief pipe 55 for selectively discharging air in the float chamber 34. It has an electromagnetic valve 56. The solenoid valve 56 is opened and closed by activating a solenoid S connected to the control device. The supernatant water discharge tank 31 and the scum discharge tanks 32, 33 each have a bottomed box-like body having an open top. And dams 31a, 33a for allowing the supernatant water to flow into the supernatant water discharge tank 31 and weirs 32a, 33a for allowing the scum to flow into the scum discharge tanks 32, 33 at predetermined locations on the upper edge. Are respectively formed.

In order to discharge the supernatant water flowing into the supernatant water discharge tank 31 to the outside of the treatment tank 11, a discharge pipe 20 extending downward from a bottom wall (not shown) of the supernatant water discharge tank 31 is provided with the scum. In order to discharge the scum that has flowed into the discharge tanks 32 and 33 to the outside of the processing tank 11, discharge pipes 21 and 22 extending downward from the bottom walls S1 of the scum discharge tanks 32 and 33 are provided, respectively.

As shown in FIG. 1, the discharge pipes 21 and 22 are disposed at symmetrical positions around the discharge pipe 20.
The discharge pipe 21 is disposed on the side wall 35 of the discharge unit 30 in the scum discharge tank 32, and the discharge pipe 22 is disposed on the side wall 36 of the discharge unit 30 in the scum discharge tank 33. Then, as shown in FIG. 5, the bottom wall S1 of the scum discharge tank 32 is inclined so as to become lower as it goes closer to the portion where the discharge pipe 21 is connected. In addition, the bottom wall S1 of the scum discharge tank 33 is
2 is inclined so as to become lower as it comes closer to the connected portion. Therefore, the scum discharge tanks 32, 33
The scum flowing into the inside flows toward the discharge pipes 21 and 22 on the bottom wall S1, respectively, and enters the discharge pipes 21 and 22.

Each of the discharge pipes 20 to 22 has a bellows structure so that the discharge pipes 20 to 22 can expand and contract with the vertical movement of the discharge unit 30. Connection pipes 24 to 26 fixed to 12
Linked to Further, the supernatant water discharge tank 31 can be moved up and down relatively to the scum discharge tanks 32 and 33. To this end, guide plates 37 and 38 are provided on the side walls 35 and 36 of the discharge unit 30, respectively, and the guide plates 37 and 38 are provided on the side walls 43 and 44 of the supernatant water discharge tank 31, respectively.
Projecting pieces 45 and 46 are formed along the guide.

In order to move the supernatant water discharge tank 31 downward with respect to the scum discharge tanks 32 and 33 and stop it at a predetermined position, the guide plates 37 and 3 are used.
8, a stopper (not shown) is provided. 28 is connected to the connecting tubes 25 and 26, a sleeve tube surrounding the connecting tube 24, and 54 is halved,
Is a protective tube. In addition, 51 to 53 each have an upper end fixed to the bottom wall of the work table 13 and a discharge pipe 20.
, And the guide pipes 51 to 53 guide the discharge pipes 20 to 22 to expand and contract.

Next, the operation of the supernatant water discharging device having the above-described structure will be described. FIG. 3 is a process diagram of the batch activated sludge method in the first embodiment of the present invention, FIG. 8 is a scum discharge process diagram in the first embodiment of the present invention, and FIG. 9 is a first embodiment of the present invention. FIG. 10 is a time chart of the supernatant water discharging device according to the first embodiment of the present invention.

In this case, inflow, agitation, aeration, sedimentation, sprinkling, and discharge of scum and supernatant water are performed sequentially according to a time schedule shown in FIG. 10 set by a control device (not shown). Step S11 When the previous supernatant water discharging step is completed,
In the inflow step, the water to be treated is caused to flow into the treatment tank 11 (FIG. 4), and the highest water level _WH is obtained. Activated sludge for performing biological treatment is accommodated in the treatment tank 11. At this time, the inverter motor 15 (FIG. 6)
Is driven, and the discharge unit 30 operates at a high speed (60 [Hz]).
Is moved upward and is placed at the first position A. In addition,
In the present embodiment, the first position A is set at a distance of 850 [mm] from the bottom wall of the processing tank 11.

When the discharge unit 30 is placed at the first position A, the lower edge of the supernatant water discharge tank 31 and the maximum water level W _H
Is about 200 mm, and the float chamber 3
Air is allowed to enter the inside 4. Step S12 In the aeration and stirring step, the treatment tank 1
In FIG. 1, air is injected into the water to be treated through a nozzle or the like (not shown) by a blower or the like (not shown), and aeration and agitation are performed. As a result, the microorganisms in the activated sludge decompose organic matter in the water to be treated into carbon dioxide and water, and the microorganisms themselves proliferate. Step S13 When the aeration and stirring are stopped, the activated sludge descends and precipitates in the treatment tank 11 in the precipitation step, and supernatant water is obtained above the treatment tank 11. And
Simultaneously with the completion of the settling process, the solenoid valve 56 is closed, and the discharge unit 30 is moved downward to land at the second position B. At this time, the scum discharge tank 32,
33 of the weir portions 32a, 33a are placed at the same height as the highest water level W _H.

The supernatant water discharge tank 31 rises 100 [mm] along the guide plates 37 (FIG. 1) and 38 by buoyancy generated by the float chamber 34. At this time, the weir portion 31a of the supernatant water discharge tank 31
Are the weir portions 32a, 33a of the scum discharge tanks 32, 33
25 [mm] higher. Step S14 In order to bring the scum around the supernatant water discharging device to the discharging unit 30, in the watering step, water is sprayed on the water surface toward the discharging unit 30 for a set time. Step S15 In the scum discharging step, as shown in FIG. 8, the discharging unit 30 is moved downward by a set distance at a low speed. At this time, the scum floating on the surface of the water to be treated flows into the scum discharge tanks 32 and 33 over the weirs 32a and 33a, and is discharged through the discharge pipes 21 and 22. During this time, since the solenoid valve 56 is closed, the supernatant water discharge tank 31 floats above the water to be treated by the buoyancy generated by the float chamber 34, and the weir portion 31 a of the supernatant water discharge tank 31 becomes the scum discharge tank 32. , 3
The third weir 32a, 33a is always higher. Step S16 In the supernatant water discharging step, the control device operates the solenoid S to open the solenoid valve 56. As a result, the air in the float chamber 34 is released through the escape pipe 55, and the float chamber 34 loses buoyancy.
8, and is moved downward by its own weight.
6 hits a stopper (not shown) and is stopped at a predetermined position.

At this time, the weir portion 3 of the supernatant water discharge tank 31
1a is a weir portion 32a, 33 of the scum discharge tank 32, 33.
Since it is lower than a, the supernatant water flows into the supernatant water discharge tank 31 through the weir portion 31a and is discharged through the discharge pipe 20. Thereafter, the discharge unit 30 is moved downward at a low speed, and stopped when reaching the third position C. During this time, the moving speed of the discharge unit 30 is set in accordance with the lowering speed of the surface of the water to be treated due to the discharge of the supernatant water, and the weir portion 31a of the supernatant water discharge tank 31
Since the scum discharge tanks 32 and 33 are always lower than the weir portions 32a and 33a, the supernatant water is continuously allowed to flow into the supernatant water discharge tank 31 and the scum discharge tanks 32 and 33 are provided.
Do not enter inside.

As described above, the discharge unit 30
Since scum can flow into the scum discharge tanks 32 and 33 and supernatant water can flow into the supernatant water discharge tank 31 and be discharged therefrom, scum does not remain in the treatment tank 11. Therefore, a vacuum device or the like becomes unnecessary. As a result, not only can the operation for discharging the scum be simplified, but also the cost of wastewater treatment can be reduced.

Next, a second embodiment of the present invention will be described. FIG. 11 is a perspective view of a discharge unit according to the second embodiment of the present invention, and FIG. 12 is a side view of a supernatant water discharge device according to the second embodiment of the present invention. In addition, about what has the same structure as 1st Embodiment, the description is abbreviate | omitted by attaching | subjecting the same code | symbol.

In this case, in order to discharge the supernatant water flowing into the supernatant water discharge tank 31 out of the treatment tank 11 (FIG. 4),
A discharge pipe 120 extending downward from a bottom wall (not shown) of the supernatant water discharge tank 31 discharges the scum flowing into the scum discharge tanks 32 and 33 to the outside of the processing tank 11. Discharge pipes 121 and 122 extending downward from each bottom wall S1 are provided, respectively.

As shown in FIG. 11, the discharge pipes 121 and 122 are disposed at symmetrical positions around the discharge pipe 120, and are connected to a common discharge pipe 123 together with the discharge pipe 120. The lower end of the discharge pipe 123 is connected to a connection pipe 124 fixed to the frame 12, and the connection pipe 124 is branched into a supernatant water discharge line 125 and a scum discharge line 126 in the treatment layer 11. Can be
Further, the supernatant water discharge valve 12 is connected to the supernatant water discharge line 125.
8, a scum discharge valve 129 is provided in the scum discharge line 126, and when discharging the supernatant water, the supernatant water discharge valve 128 is opened and the scum discharge valve 129 is closed. When the scum is discharged, the scum discharge valve 1
29 is opened and the supernatant water discharge valve 128 is closed.

The discharge pipe 123 has a bellows structure and is guided by a guide rod 51 to expand and contract as the discharge unit 30 moves up and down. When shifting from the scum discharging process to the supernatant water discharging process, the solenoid valve 5
Even if 6 is opened and the discharge of the supernatant water is started, the scum discharge valve 129 is kept open until the scum remaining in the discharge pipe 123 is washed by the supernatant water. Thereafter, when the set time elapses, the scum discharge valve 129 is closed, and the supernatant water discharge valve 128 is opened.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0028]

As described above in detail, according to the present invention, in the supernatant water discharging apparatus, a discharging unit arranged vertically movably and a driving means for moving the discharging unit up and down are provided. Having. The discharge unit has an open upper portion, a scum discharge tank to which a discharge pipe for discharging scum is connected, and is disposed to be vertically movable with respect to the scum discharge tank. A supernatant water discharge tank to which a discharge pipe for discharging is connected, a float chamber integrally formed with the supernatant water discharge tank, a lower part being opened, and an upper wall forming a closed space, and air in the float chamber being formed. An opening / closing means for selectively discharging is provided.

In this case, buoyancy is generated by the float chamber by moving the discharge unit up and down and supplying air to the float chamber, and the buoyancy causes the supernatant water discharge tank to rise above the scum discharge tank. It is moved to. Therefore, in this state, the scum can flow into the scum discharge tank and be discharged from the processing tank.

By discharging the air in the float chamber, buoyancy by the float chamber can be eliminated, and the supernatant water discharge tank can be moved downward with respect to the scum discharge tank. Therefore, in this state, the supernatant water can flow into the supernatant water discharge tank and be discharged from the treatment tank. As a result, a vacuum device or the like becomes unnecessary,
Not only can the operation for discharging scum be simplified, but also the cost of wastewater treatment can be reduced.

In still another apparatus for discharging supernatant water of the present invention, each of the discharge pipes is connected to a common discharge pipe for discharging scum and supernatant water, and the common discharge pipe discharges scum. And a scum discharge line for discharging the supernatant water. In this case, the scum and the supernatant water flow through a common discharge pipe and are discharged via a supernatant water discharge line or a scum discharge line.

[Brief description of the drawings]

FIG. 1 is a perspective view of a discharge unit according to a first embodiment of the present invention.

FIG. 2 is a process diagram of a conventional batch activated sludge method.

FIG. 3 is a process chart of a batch activated sludge method according to the first embodiment of the present invention.

FIG. 4 is a front view of the supernatant water discharging device according to the first embodiment of the present invention.

FIG. 5 is a side view of the supernatant water discharging device according to the first embodiment of the present invention.

FIG. 6 is a plan view of the supernatant water discharge device according to the first embodiment of the present invention.

FIG. 7 is a support state diagram of the discharge unit according to the first embodiment of the present invention.

FIG. 8 is a diagram illustrating a scum discharging process according to the first embodiment of the present invention.

FIG. 9 is a view showing a supernatant water discharging step according to the first embodiment of the present invention.

FIG. 10 is a time chart of the supernatant water discharging device according to the first embodiment of the present invention.

FIG. 11 is a perspective view of a discharge unit according to a second embodiment of the present invention.

FIG. 12 is a side view of a supernatant water discharging device according to a second embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 15 inverter motor 20-22, 120-123 discharge pipe 30 discharge unit 31 supernatant water discharge tank 32, 33 scum discharge tank 34 float chamber 56 solenoid valve 125 supernatant water discharge line 126 scum discharge line

Claims (3)

(57) [Claims] 1. An image forming apparatus comprising: (a) a discharging unit movably arranged in a vertical direction; and (b) driving means for vertically moving the discharging unit, and (c) an upper part of the discharging unit is open. A scum discharge tank to which a discharge pipe for discharging scum is connected; a scum discharge tank disposed movably up and down with respect to the scum discharge tank; an upper part being opened; and a discharge pipe connected to a discharge pipe for discharging supernatant water. A discharge tank, a float chamber integrally formed with the supernatant water discharge tank, a lower part being opened, and a top wall forming a closed space; and an opening / closing means for selectively discharging air in the float chamber. A supernatant water discharging device. (A) a control device; (b) the control device closes the opening / closing means in a scum discharging step;
By generating buoyancy by the float chamber and moving the supernatant water discharge tank upward with respect to the scum discharge tank, opening the opening and closing means in the supernatant water discharge step,
The buoyancy of the float chamber is eliminated, and the supernatant water discharge tank is moved downward with respect to the scum discharge tank.
The supernatant water discharging device according to the above. 3. Each of the discharge pipes is connected to a common discharge pipe for discharging scum and supernatant water, wherein the common discharge pipe has a scum discharge line for discharging scum and a discharge pipe for discharging supernatant water. And a branch to a supernatant water discharge line.
The supernatant water discharging device according to the above.