JPH08267079A - Sewage treating device - Google Patents

Abstract

PURPOSE: To prevent the degradation in the quality of purified water without rapidly increasing the volume of the sewage in a septic tank by providing this septic tank with a filter bed stuck with microorganisms and installing a buffer tank packed with fine wooden pieces to the septic tank at the time of subjecting the sewage to a purification treatment with the microorganisms of this filter bed. CONSTITUTION: The sewage 3 is first supplied to a buffer tank 5 by a supply pipe 6 in the case the purification treatment of the sewage 3 is executed. The supplied sewage 3, then, flows down gradually while oozing to a fine wooden pieces 4 and passing the gaps among the fine wooden pieces 4. This sewage is discharged from a drain port 7 into an anaerobic treating vessel 11. The sewage is anaerobically treated by the effect of the anaerobic bacteria sticking to an anaerobic filter bed 13. The sewage flows from an overflow section 17 into an aerobic treating vessel 12 and is then aerobically treated by the aerobic bacteria sticking to an aerobic filter bed 14 and the air supplied from an air diffusion pipe 15. The purified water subjected to the purification treatment is thereafter flows from a communicating section 24 to a settling tank 23 where sludge is precipitated. The treated water is discharged out of an outflow port 16 through a disinfecting vessel 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water purification device for purifying sewage.

[0002]

2. Description of the Related Art FIG. 8 shows an example of a conventionally used sewage treatment apparatus. Reference numeral 1 is a septic tank called a combined treatment tank, and the inside of the septic tank 1 is an anaerobic treatment tank 1
1 and an aerobic treatment tank 12. The anaerobic treatment tank 11 has an anaerobic filter bed 13 to which a biofilm formed by anaerobic bacteria is attached, and a supply pipe 6 for supplying the sewage 3.
Is provided. The aerobic treatment tank 12 has an aerobic filter bed 14 to which a biofilm formed by aerobic bacteria is attached, an aeration pipe 15 for supplying air into the aerobic treatment tank 12, and purified water. Outlet 1 for discharging to outside of septic tank 1
6 are provided.

In purifying the sewage 3 with such a sewage treatment apparatus, the anaerobic treatment tank 11 is supplied from the supply pipe 6.
Sewage 3 is supplied to the sewage and sewage 3 is anaerobically treated with anaerobic bacteria,
After that, the sewage 3 is allowed to flow into the aerobic treatment tank 12 through the overflow section 17 to aerobically treat the sewage 3 with aerobic bacteria, and then the purified water is discharged from the outlet 16. You can

[0004]

However, in the above-mentioned conventional example, since the sewage having a large fluctuation in the inflow amount is directly introduced into the anaerobic treatment tank 11 from the supply pipe 6, it is introduced into the anaerobic treatment tank 11. When the amount of sewage increases sharply, the biofilm of anaerobic bacteria adhering to the anaerobic filter bed 13 may peel off and flow out. Therefore, the sewage 3 is sufficiently anaerobically treated in the anaerobic treatment tank 11. However, the quality of the purified water discharged from the outflow port 16 may be deteriorated. Therefore, it has been attempted to provide a pump or the like on the supply pipe 6 to adjust the inflow amount from the supply pipe 6, but there has been a problem that the structure becomes complicated and the cost becomes high.

Further, in the above-mentioned conventional example, the sludge 18 generated by the anaerobic treatment of the sewage 3 is stored in the anaerobic treatment tank 11 for a certain period of time, and then the sludge 18 is taken out for incineration or the like. A space for accumulating 18 for a certain period has to be secured in the septic tank 1, and there is a problem that the device cannot be downsized.

The present invention has been made in view of the above points, and it is possible to prevent the quality of purified water from deteriorating without complicating the structure and increasing the cost, and to reduce the size. An object of the present invention is to provide a sewage treatment apparatus capable of performing the above.

[0007]

In the sewage treatment apparatus according to the present invention, a septic tank 1 is provided with a filter bed 2 on which microorganisms are adhered, the sewage 3 is introduced into the septic tank 1 and the sewage is purified by the microorganisms on the filter bed 2. In the sewage treatment apparatus adapted to treat, the septic tank 1 is provided with a buffer tank 5 filled with wood chips 4, and the sewage 3
Is provided in the septic tank 1, and a drainage port 7 for discharging the sewage 3 to the septic tank 1 is formed in the buffer tank 5.

Further, in the wastewater treatment apparatus according to the present invention, the septic tank 1 is provided with a filter bed 2 on which microorganisms are adhered, and the wastewater 3 is introduced into the septic tank 1 and the microorganisms in the filter bed 2 purify the wastewater 3. In the treated sewage treatment apparatus, the filtration tank 9 in which the wood strips 4 are filled above the surface of the sewage 3 in the septic tank 1
And a transfer pipe 10 for transferring sludge generated in the septic tank 1 to the filtration tank 9 by the purification treatment of the septic water 3 is installed in the septic tank 1
And the drainage port 7 for discharging the water in the sludge in the filtration tank 9 to the purification tank 1 is formed in the filtration tank 9.

Further, in the wastewater treatment apparatus according to the present invention, the septic tank 1 is provided with the filter bed 2 on which microorganisms are adhered, the wastewater 3 is introduced into the septic tank 1, and the microorganisms in the filter bed 2 are used to purify the wastewater 3. In the sewage treatment apparatus described above, the septic tank 1 is provided with the sludge treatment tank 8 filled with the wood strips 4, and the wood strips 4 are caused to parasitize microorganisms that decompose the sludge generated in the septic tank 1 by the purification treatment of the waste water 3 to remove sludge. A sewage treatment apparatus comprising a transfer pipe 10 for transferring from the septic tank 1 to the sludge treatment tank 8.

[0010]

Function: The septic tank 1 is provided with the buffer tank 5 filled with the wooden strips 4, the supply pipe 6 for supplying the dirty water 3 to the buffer tank 5 is provided in the septic tank 1, and the drainage for discharging the dirty water 3 to the septic tank 1 is provided. Since the mouth 7 is formed in the buffer tank 5, the waste water 3 is supplied to the buffer tank 5 by supplying the waste water 3 from the supply pipe 6 to the buffer tank 5 and the waste water 3 from the buffer tank 5 to the septic tank 1 through the drainage port 7. The sewage 3 which has been subjected to water resistance due to the wood strips 4 gradually flows through the buffer tank 5 and is then discharged from the drainage port 7 to the septic tank 1. Therefore, the sewage 3 is directly supplied from the supply pipe 6 to the septic tank. Sewage 3 in septic tank 1 rather than supplying 3
The amount of can be prevented from increasing rapidly.

Further, a filtration tank 9 filled with wood chips 4 is provided above the surface of the wastewater 3 in the septic tank 1, and the sludge generated in the septic tank 1 by the purification treatment of the wastewater 3 is transferred to the filtration tank 9. The pipe 10 is provided in the septic tank 1 and the filtration tank 9 is provided.
Drainage port 7 for discharging the water in the sludge inside to the septic tank 1
Since it is formed in the filter tank 9, the water contained in the sludge can be filtered by the wood strips 4 to capture the solid content of the sludge in the filter tank 9 to condense and reduce the volume, and also from the drain port 7. Water in sludge can be discharged.

Further, the sludge treatment tank 8 filled with the wood strips 4 is provided in the septic tank 1, and the wood strips 4 are made to parasitize microorganisms which decompose sludge generated in the septic tank 1 by the purifying process of the wastewater 3 to sludge the septic tank 1 Since the transfer pipe 10 for transferring the sludge to the sludge treatment tank 8 is provided, the sludge can be decomposed by the microorganisms parasitic on the wood strips 4 to reduce the sludge.

[0013]

EXAMPLES The present invention will be described in detail below with reference to examples. FIG.
Shows an embodiment of the present invention. Reference numeral 1 denotes a septic tank called a combined treatment tank, and the inside of the septic tank 1 is divided by a partition plate 21 and a dividing plate 22 into an anaerobic treatment tank 11, an aerobic treatment tank 12, and a precipitation tank 23. An inspection port 26 is provided on each upper surface of the anaerobic treatment tank 11 and the aerobic treatment tank 12. The anaerobic treatment tank 11 has an anaerobic filter bed 13 as a filter bed 2 to which a biofilm formed by anaerobic bacteria is attached.
A supply pipe 6 for supplying the sewage 3 and an overflow section 17 for connecting the anaerobic treatment tank 11 and the aerobic treatment tank 12 are provided. The aerobic treatment tank 12 is provided with an aerobic filter bed 14 as a filter bed 2 to which a biofilm formed by aerobic bacteria is attached, and an air diffuser pipe 15 for supplying air into the aerobic treatment tank 12. is there. Further, the aerobic treatment tank 12 is provided with a transport pipe 25 for transporting sludge generated in the aerobic treatment of the wastewater 3 and sludge settled in the settling tank 23 to the anaerobic treatment tank 11.

The settling tank 23 is a tank for precipitating sludge contained in the purified water purified by the anaerobic treatment tank 11 and the aerobic treatment tank 12.
4, the aerobic treatment tank 12 and the precipitation tank 23 are communicated with each other. In the settling tank 23, a disinfection tank 25 for disinfecting the purified water purified by the anaerobic treatment tank 11 and the aerobic treatment tank 12, and water purified by being connected to the disinfection tank 25 to the outside of the purification tank 1. An outlet 16 is provided for discharging.

In the anaerobic treatment tank 11, wastewater 3 in the tank
A buffer tank 5 is removably arranged between the water surface of and the supply pipe 6. The buffer tank 5 is formed of a box having an open top surface and a volume of 40 to 50 liters. The buffer tank 5 is provided with a large number of drainage ports 7 on its side surface and bottom surface, and the buffer tank 5 has wood chips (sawdust). ) 4 is filled. In purifying the sewage 3 with the sewage treatment apparatus thus formed, the sewage 3 is first supplied from the supply pipe 6 to the buffer tank 5. The sewage 3 supplied to the buffer tank 5 permeates the wood strips 4 or passes through the gaps between the wood strips 4 and gradually flows down,
It is discharged from the drainage port 7 to the anaerobic treatment tank 11. After this, the sewage 3 is subjected to anaerobic treatment in the anaerobic treatment tank 11 by the action of anaerobic bacteria adhering to the anaerobic filter bed 13 to be purified. After that, the sewage 3 flows from the anaerobic treatment tank 11 into the aerobic treatment tank 12 by overflow from the overflow section 17.
Then, the sewage 3 is purified in the aerobic treatment tank 12 by aerobic treatment (aeration treatment) with aerobic bacteria adhering to the aerobic filter bed 14 and air supplied from the air diffuser 15 to the sewage 3. After that, the purified water purified by the anaerobic treatment tank 11 and the aerobic treatment tank 12 flows into the settling tank 23 from the communicating portion 24 to cause sludge to settle there, passes through the disinfection tank 25, and flows from the outlet 16 to the purification tank. 1 is discharged to the outside.

In the above embodiment, the sewage water 3 was supplied from the supply pipe 6 to the buffer tank 5, so that the sewage water 3 slowly passed through the buffer tank 5 due to the resistance of the wood strips 4 to pass through the anaerobic treatment tank. 1
Therefore, the amount of the sewage 3 supplied to the anaerobic treatment tank 11 can be made smaller than the amount of the sewage 3 per unit time passing through the supply pipe 6, and the anaerobic property can be reduced. It is possible to prevent the amount of the dirty water 3 in the processing tank 11 from rapidly increasing. Therefore, the microbial film attached to the anaerobic filter bed 13 can be prevented from separating and flowing out, and the sewage from the supply pipe 6 is not subjected to anaerobic treatment, and the overflow portion 17 is transferred to the aerobic treatment tank 12. It is possible to prevent a so-called short-circuit flow that flows.

FIG. 2 shows another embodiment. In this embodiment, in the anaerobic treatment tank 11, the filtration tank 9 is arranged above the water surface of the dirty water 3 in the tank. The filtration tank 9 is formed of a box having an upper surface opened and a volume of 40 to 50 liters, and a large number of drainage ports 7 are provided on the side surface and the bottom surface thereof. ) 4 is filled.

Further, the anaerobic treatment tank 11 is provided with an anaerobic sludge transfer pipe 10a as a transfer pipe 10 for conveying the sludge generated by the anaerobic treatment of the wastewater 3 to the filtration tank 9. The sludge transfer pipe 10a has an anaerobic treatment tank 11 at the lower end.
And the upper end is opened above the filter tank 9. Further, the aerobic sludge transfer pipe 10b is provided in the aerobic treatment tank 12 as a transfer pipe 10 for transporting sludge generated by the aerobic treatment of the wastewater 3 to the filtration tank 9, and the aerobic sludge transfer pipe is provided. 10b is the lower end of the lower part of the aerobic treatment tank 12,
The upper ends are opened above the filtration tank 9. Each transfer pipe 10 is provided with a pump such as an air lift, and sludge is periodically (about once every 6 months) from the anaerobic treatment tank 11 or the aerobic treatment tank 12 to the filtration tank 9 by this pump. It is transferred to.

In purifying the sewage 3 with the sewage treatment apparatus thus formed, after the sewage 3 is directly supplied from the supply pipe 6 to the anaerobic treatment tank 11, the sewage is treated in the same manner as in the above embodiment. 3 is anaerobically treated in the anaerobic treatment tank 11, and aerobically treated in the aerobic treatment tank 12, and the precipitation tank 2
3. Outflow from the outlet 16 through the disinfection tank 25 to the outside of the septic tank 1. In the sewage treatment apparatus, sludge generated by anaerobic treatment of the sewage 3 in the anaerobic treatment tank 11 is pumped up by the anaerobic sludge transfer pipe 10a and discharged into the filtration tank 9, and the sewage 3 is treated in the aerobic treatment tank 12 by the aerobic treatment tank 12. Sludge generated by the aerobic treatment is pumped up by the aerobic sludge transfer pipe 10b and discharged to the filtration tank 9. The sludge pumped up is filtered by the wood strips 4, only the solid content in the sludge remains in the filtration tank 9, and the water content in the sludge is discharged to the anaerobic treatment tank 11 through the drainage port 7.

In the above-described embodiment, the sludge generated in the anaerobic treatment tank 11 is pumped up by the anaerobic sludge transfer pipe 10a to be filtered in the filtration tank 9.
The sludge generated in the aerobic treatment tank 12 is pumped up by the aerobic sludge transfer pipe 10b and the filtration tank 9 is discharged.
The sludge can be dehydrated and concentrated easily by filtering the water contained in the sludge in an amount of 90 wt% or more with the wood strips 4, so that the anaerobic treatment tank 11 and the aerobic treatment can be performed. It is not necessary to secure a space for storing sludge in the tank 12. The sludge concentrated in the filtration tank 9 can be composted in a certain period (about 6 months) and used as compost. In addition, wood strip 4
Alternatively, the solid content remaining in the filtration tank 9 may be decomposed into water and gas by the microorganisms.

FIG. 3 shows another embodiment of the present invention. In this embodiment, a wood debris filling tank 30 having both the functions of the buffer tank 5 and the filtration tank 9 of the above embodiment is provided between the water surface of the sewage 3 in the tank and the supply pipe 6 to fill the wood debris. The tank 30 is filled with wood chips (sawdust) 4. Further, in the anaerobic treatment tank 11 and the aerobic treatment tank 12, the same anaerobic sludge transfer pipe 10a and aerobic sludge transfer pipe 10 as in the above-described embodiment are used.
b are provided respectively.

In this embodiment, the wood debris filling tank 30 can function as both the buffer tank 5 and the filtration tank 9. FIG. 4 shows still another embodiment of the present invention. In this embodiment, a stirring device 20 formed by providing a plurality of stirring blades 32 around a rotating shaft 31 is rotatably provided in the filtration tank 9 of the embodiment shown in FIG. The piece 4 is formed by allowing a microorganism that decomposes sludge to parasitize. In this one, the agitator 20 can be used to mix and stir the wood chips 4 and the sludge to enhance the contact between them, and at the same time, the air can be sufficiently taken into the mixture, so that the sludge can be decomposed efficiently. Can be increased.

FIG. 5 shows still another embodiment.
In this embodiment, a sludge treatment tank 8 is formed adjacent to the septic tank 1. As shown in FIG. 6, the septic tank 1 has an upper surface opened, and an air diffuser 15 having a large number of holes on the outer surface is disposed inside, and the upper side of the air diffuser 15 is formed of aerobic bacteria. It is formed as an aerobic treatment tank 12 provided with an aerobic filter bed 14 to which a biofilm is attached, and below the diffuser pipe 15 is formed as an anaerobic treatment tank 11. The air diffuser 15 is connected to a pump 47 formed of an air blower or the like via a connecting pipe 48. Reference numeral 23 is a precipitation tank formed by being divided from the aerobic treatment tank 12 by a dividing plate 22, and the bottom of the precipitation tank 23 is communicated with the anaerobic treatment tank 11 by a communication portion 24. A pump 50 formed by an air lift or the like is provided in the middle of the transfer pipe 10, and the lower end of the transfer pipe 10 is opened at the lower part of the anaerobic treatment tank 11.

In purifying the sewage 3 in the septic tank 1, the sewage 3 is first supplied from the top opening of the septic tank 1 as shown by the arrow a. Next, the pump 47 is operated to send air to the air diffuser pipe 15 via the connecting pipe 48, and bubble air is discharged from the air diffuser pipe 15 to the dirty water 3 in the aerobic treatment tank 12. Here, the sewage 3 is aerated with aerobic bacteria adhering to the aerobic filter bed 14 and the air supplied from the air diffuser 15. Next, the aeration-treated wastewater 3 flows into the anaerobic treatment tank 11, where the wastewater is anaerobically treated and sludge is decomposed. After that, the sewage 3 flows into the settling tank 23 to precipitate the sludge contained in the sewage 3, and the supernatant liquid is discharged to the outside of the septic tank 1 as shown by the arrow B. In addition, dirty water 3
May be made to reciprocate between the aerobic treatment tank 12 and the anaerobic treatment tank 11, whereby the sewage 3 can be repeatedly subjected to aerobic treatment or anaerobic treatment.

When the anaerobic treatment and the aerobic treatment of the sewage 3 and the sludge settling in the settling tank 23 are performed as described above, heavy SS components in the anaerobic treatment tank 11 and biofilms peeled from the filter bed 14 are sludge. The sludge 18 precipitates as 18, but the sludge 18 is pumped through the transfer pipe 10 by operating the pump 50. Then, the sludge 18 pumped up is sent to the garbage treatment device or the sludge treatment tank 8 and decomposed.

In the conventional aerobic treatment method of sewage, although the purification efficiency is high, the amount of sludge (excess sludge) is large, and the management, treatment and disposal of sludge have become major problems. In addition, the conventional anaerobic treatment method for wastewater has advantages such as low power cost, solubilization of solid organic matter, and small amount of sludge generation.
On the other hand, there were problems such as a slow reaction rate and generation of a foul odor. Further, conventionally, the ammonia nitrogen contained in the anaerobic-treated wastewater is aerobically treated to be oxidized to nitrite nitrogen or nitrate nitrogen, and further N _{2 is} deoxidized by the denitrifying bacteria in the aerobic treatment tank.
However, in order to do this, the sewage treated in the anaerobic treatment tank must be returned to the aerobic treatment tank again, and a return pipe is required. Alternatively, if the above process is carried out in one reaction tank, there is a problem that intermittent aeration operation is required and the control mechanism becomes complicated.

However, in the septic tank 1 of the present embodiment, the aerobic treatment tank 12 and the anaerobic treatment tank 11 are mixed in one septic tank 1, so that both the aerobic treatment and the anaerobic treatment should be performed on the wastewater 3. It is possible to reduce the generation of sludge, and by performing anaerobic treatment after aerobic treatment, the sewage 3 can be subjected to a denitrification reaction, and nitrogen in the sewage 3 can be easily removed. it can. In addition, there is no need for a return pipe or the like for returning sewage, and there is no need for intermittent aeration operation and the control mechanism is not complicated. As shown in FIG. 7, two septic tanks 1 may be installed side by side.

In this embodiment, a sludge treatment tank 8 is provided beside the septic tank 1. The sludge treatment tank 8 is filled with the wood strips 4, and a stirring device 20 having a plurality of stirring stages 32 provided around the rotating shaft 31 is disposed. Stirrer 2
0 is rotationally driven by a motor 40 arranged below it. That is, the driving pulley 4 provided on the rotation shaft of the motor 40
3 and a driven pulley 42 provided on the rotary shaft 31 of the stirring device 20 are connected by a belt 41, and the drive of the motor 43 is transmitted via the driven pulley 43, the driven pulley 42, and the belt 41. Reference numeral 44 denotes a fan, which discharges gas generated by sludge treatment from an exhaust port 46.

In this embodiment, sludge 1 generated in the septic tank 1
8 is pumped up by the pump 50 and the sludge treatment tank 8 is transferred by the transfer pipe 10.
It is designed to be transported to. The sludge 18 is decomposed into gas and water by microorganisms parasitic on the wood chips 4. As described above, in the present embodiment, the sludge can be decomposed by the microorganisms parasitic on the wood chips 4 to reduce the amount of the sludge 18, and it is not necessary to secure a space for accumulating the sludge in the septic tank 1 and the size can be reduced. Is what you can do. Further, it is possible to treat the sludge in a self-contained manner so as not to be discharged outside the sludge treatment tank 8.

[0030]

As described above, according to the present invention, the septic tank is provided with the buffer tank filled with the wood chips, the supply pipe for supplying the waste water to the buffer tank is provided in the septic tank, and the waste water is discharged to the septic tank. Since the drainage port was formed in the buffer tank, by supplying the wastewater from the supply pipe to the buffer tank and supplying the wastewater from the buffer tank to the septic tank through the drainage port, the wastewater supplied to the buffer tank is passed by the wood strips. After gradually flowing in the buffer tank due to water resistance, it will be discharged to the septic tank from the drain port, so the amount of wastewater in the septic tank will increase rapidly compared to directly supplying wastewater to the septic tank from the supply pipe. It is possible to prevent the deterioration of the quality of the purified water without complicating the structure and increasing the cost.

Further, a filter tank filled with wood chips is provided above the surface of the wastewater in the septic tank, and a transfer pipe for transferring sludge generated in the septic tank to the filter tank by the purification treatment of the wastewater is provided in the septic tank and filtered. Since the drainage port for discharging the water in the sludge in the tank to the septic tank is formed in the filter tank, the water contained in the sludge can be filtered with wood strips,
The sludge can be concentrated and reduced in volume, and it is not necessary to secure a space for accumulating the sludge in the septic tank, and the size can be reduced.

Further, a sludge treatment tank filled with wood debris is provided in the septic tank, and the wood debris is transferred from the septic tank to the sludge treatment tank by causing the microorganisms that decompose the sludge generated in the septic tank by the purification treatment of the waste water to parasitize. Since it is equipped with a transfer pipe for reducing the amount of sludge by decomposing sludge with microorganisms parasitic on wood chips, it is not necessary to secure a space for accumulating sludge in the septic tank and downsizing. Is something that can be done.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing another embodiment of the above.

3A is a side sectional view showing still another embodiment of the same, and FIG. 3B is a top sectional view.

FIG. 4 is a sectional view showing still another embodiment of the above.

FIG. 5 is a sectional view showing still another embodiment of the above.

FIG. 6 is a cross-sectional view showing the septic tank used in FIG. 5 above.

FIG. 7 is a cross-sectional view showing another embodiment of the above septic tank.

FIG. 8 is a sectional view showing a conventional example.

[Explanation of symbols]

 1 Septic tank 2 Filter bed 3 Sewage 4 Wood debris 5 Buffer tank 6 Supply pipe 7 Drainage port 8 Sludge treatment tank 9 Filtration tank 10 Transfer pipe

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Akio Kubota 1048, Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Hideaki Yamada, 1048, Kadoma, Kadoma City, Osaka Matsushita Electric Co., Ltd.

Claims (3)

[Claims] 1. A sewage treatment apparatus in which a septic tank is provided with a filter bed to which microorganisms are attached, and sewage is introduced into the septic tank and sewage is purified by the microorganisms of the filter bed. The septic tank is filled with wood chips. A sewage treatment apparatus comprising a buffer tank, a supply pipe for supplying sewage to the buffer tank, and a drainage port for discharging sewage into the buffer tank. 2. A sewage treatment apparatus in which a septic tank is provided with a filter bed to which microorganisms are adhered, and sewage is made to flow into the septic tank, and sewage is purified by the microorganisms of the filter bed. A filter tank filled with wood chips is installed in the filter tank, and a transfer pipe for transferring sludge generated in the filter tank to the filter tank is installed in the filter tank, and water in the filter tank is discharged to the filter tank. A sewage treatment device, characterized in that a drainage port for forming the same is formed in a filtration tank. 3. A sewage treatment apparatus in which a septic tank is provided with a filter bed on which microorganisms are adhered, and sewage is introduced into the septic tank, and sewage is purified by the microorganisms of the filter bed. A sludge treatment tank is provided, and a wood pipe is provided with a transfer pipe for causing microorganisms that decompose sludge generated in the septic tank by the purification treatment of the wastewater to parasitize and transfer the sludge from the septic tank to the sludge treatment tank. Sewage treatment equipment to be.