JPH0230756B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a contact type sewage treatment device for purifying sewage containing organic matter such as domestic wastewater.

(Prior art) As one type of contact type sewage treatment equipment, the sewage treatment system has a first flow path that causes the sewage that has entered the septic tank to flow from the upper part of the septic layer to the lower part of the septic layer, and a sewage that flows out from the first flow path. The septic tank includes a second flow path that causes the water to flow from the bottom to the top of the septic tank, and a third flow path that receives the wastewater that has reached the top of the second flow path,
A contact body to which aerobic microorganisms adhere is placed in the second flow path, an aeration pipe is placed below the second flow path, and the clean water in the third flow path is caused to flow out of the septic tank. There is a construction device.

However, in the conventional sewage treatment equipment, the first,
Since the second and third flow paths communicate with each other at the bottom of the septic tank, the wastewater that has entered the septic tank flows directly from the first flow path through the bottom of the septic tank to the third flow path, and There is a risk that the water may flow out of the septic tank from the outlet that communicates with the flow path. Therefore, in the conventional sewage treatment apparatus, the sewage flow path in the septic tank is short and does not function as a long waterway.

Another type of contact type sewage treatment equipment is
There is a device in which a septic tank is divided into a plurality of purification chambers through which wastewater passes sequentially, and a contact body and an aeration pipe are arranged in the intermediate purification chamber (Japanese Patent Application Laid-open No. 190693/1983). In this sewage treatment apparatus, sewage flows from the upstream purification chamber to the downstream purification chamber through an outflow portion provided at the top of a partitioning means that partitions adjacent purification chambers.

However, in the other sewage treatment equipment mentioned above, the contact body is simply deposited in the wastewater in the intermediate purification chamber, so the sewage in the intermediate purification chamber flows out to the downstream purification chamber without passing through the contact body. Resulting in.

Still another contact type sewage treatment device includes a first channel in which sewage flows from the upper part to the lower part in the septic tank, and sewage flowing out from the first channel flows from the lower part to the upper part. There is a device that is divided into a plurality of purification chambers each having a second flow path, an aeration pipe is placed at the bottom of the first flow path of each purification chamber, and a contact body is placed in the middle of the second flow path. (Jitsukai 50-111163
Publication No.). However, in this sewage treatment device, the air ejected from the aeration pipe does not rise through the contact body, so the sewage passes through the shortest distance in the contact body, that is, a specific part, and the contact body is not used effectively. In particular, when the contact body becomes clogged, a certain water line or short circuit is formed in the contact body.

(Object of the Invention) An object of the present invention is to provide a contact type sewage treatment device in which one septic tank acts as a long channel and the sewage flowing into the septic tank reliably passes through a contact body. .

Another object of the present invention is to provide a contact type sewage treatment device in which sewage is circulated through a flow path passing through a contact body, and the sewage is purified to a higher degree.

(Structure of the Invention) A sewage treatment apparatus of the present invention includes a septic tank having an inlet and an outlet for sewage, a first chamber in the septic tank that communicates with the inlet, and a first chamber that communicates with the outlet and the septic tank. a first compartment means for dividing the first compartment into a second compartment that receives wastewater flowing out from the first compartment;
a first outflow means disposed above the partitioning means and allowing the wastewater in the first room to flow out into the second room; and a plurality of purification units through which the wastewater sequentially passes through the first room. a second partitioning means for partitioning into a chamber; a second outflow means disposed above the second partitioning means and allowing the wastewater in the upstream purification chamber to flow out into the downstream purification chamber; a contacting means disposed in each of the purification chambers at a position spaced upward from the bottom thereof and for bringing the wastewater into contact with purifying microorganisms; and an aeration means disposed below the contact means, and each of the purification chambers has a flow path defining means disposed within the purification chamber to cause wastewater to flow from the upper part of the purification chamber to the lower part thereof. The contact means is divided into a first flow path and a second flow path that allows the wastewater flowing out from the lower part of the first flow path to flow from the lower part of the purification chamber to the upper part thereof, and the contact means is connected to the second flow path. is placed in the flow path.

Another sewage treatment device of the present invention further includes means for returning the sewage at the bottom of the second chamber to the vicinity of the inlet.

(Operations and Effects of the Invention) The sewage that has flowed into the first chamber sequentially flows through the purification chambers in the first chamber, and flows out from the most downstream purification chamber to the second chamber. The sewage in the second room flows out of the septic tank from the outlet. The sewage is collected in each purification room.
When flowing down the first flow path from above to below, then flowing through the second flow path from below to above while being subjected to vibrations, and flowing from below to upward through the second flow path, the contact means is applied. and then flows out from the top of the second channel into the second chamber.

Therefore, according to the invention, one septic tank acts as a long channel, and the wastewater does not flow into the downstream clarification chamber and into the second chamber unless it passes through the contact means.

In another sewage treatment apparatus of the present invention, the sewage at the bottom of the second chamber is returned to the vicinity of the inlet by the reflux means. Therefore, according to the present invention, even if the amount of sewage in the septic tank decreases, the sewage returned to the vicinity of the inlet is circulated through the flow path passing through the contact body, so that the sewage can be purified to a higher degree. Ru.

(Example) Hereinafter, an example of the present invention shown in the drawings will be described.

The sewage treatment apparatus 10 shown in FIGS. 1 to 3 includes a septic tank 12. The septic tank includes an elongated box-shaped tank body 14 that opens upward, and a tank lid 16 that closes the upper opening of the tank body, and is buried underground.
A sewage inlet 18 is provided on one longitudinal side wall of the tank body 14, and a sewage outlet 20 is provided on the other side wall at a position slightly lower than the height of the inlet 18. Inlet 18 and outlet 20
is defined by a pipe penetrating the side wall of the tank body 14 in the illustrated example.

Inside the septic tank 12, a first chamber 22 extending vertically inside the septic tank 12 is provided to divide the inside of the septic tank into a first chamber 22 on the inlet 18 side and a second chamber 24 on the outlet 20 side. A partitioning means or partition wall 26 is provided. The partition wall 26 has an upper part where the waste water is stored first.
It has an outflow portion 28 that allows outflow from the second chamber 22 to the second chamber 24. In the illustrated example, the outflow portion 28 includes a first pipe 30 extending laterally near the partition wall 26 of the first chamber 22 and having a plurality of holes, and a first pipe 30 that is connected to the first pipe and connected to the partition wall. 26 from the first chamber 22 side to the second chamber 24 side.
defined by.

Inside the first chamber 22, there are a plurality of (four in the illustrated example) purification chambers 3 through which dirty water passes sequentially.
A plurality of second partitioning means, ie, partition members 3, extend vertically within the first chamber 22 to partition the interior into four compartments.
6 is provided. A weir 38 is fitted into the upper part of each partition member 36 to allow wastewater to flow from the upstream purification chamber to the downstream purification chamber.
The weir extends through the partition member 36 from the upstream purification chamber to the downstream purification chamber, so that the wastewater in the first chamber 22 flows out from the upstream purification chamber to the downstream purification chamber. .

Each purification chamber 34 includes a flow path regulating means, that is, a flow path regulating member 4 that regulates the flow of wastewater within the purification chamber.
0 is placed. In the illustrated example, the flow path defining member is a wall extending from a position upwardly separated from the bottom of the purification chamber 34 to a position above the height of the outflow portion 28 and the weir 38 within the purification chamber. Therefore, inside each purification chamber 34, there is a first flow path 42 through which the wastewater flowing into the purification chamber flows from the upper part of the first chamber 22 to the lower part thereof, and a first flow path 42 through which the wastewater flowing out from the first flow path flows out. and a second flow path 44 that allows the wastewater to flow from the lower part of the first chamber 22 to the upper part thereof so as to reach the part 28 or the weir 38. The first and second channels 42, 44 communicate with each other at the bottom of the purification chamber 34.

A support stand 46 is arranged at the lower end of each second flow path 44 . A contact body 48 to which aerobic microorganisms for sewage purification are attached is supported on the support base 46 . The contact body is preferably made of fibrous synthetic resin because microorganisms can easily adhere thereto. The contact body 48 fills the entire space from the bottom of the second channel 44 to the bottom of the outflow section 28 or the weir 38.

A diffuser pipe 50 having a plurality of holes for blowing out air is arranged below the support base 46. The diffuser pipe is attached to a fitting 5 fixed to the support base 46 on the lower side.
2, the contact body 48 is supported in a position extending below the contact body 48 in the width direction of the tank body 14.

A downflow pipe 54 communicating with the second pipe 32 and a high-speed air lift pump 56 are arranged in the second chamber 24 . The flow pipe 54 extends vertically within the second chamber and opens downward. The air lift pump 56 extends vertically within the second chamber 24, and communicates with the upper part of the tank 14 to a pipe 58 extending in the longitudinal direction of the tank. The tube 58 is connected to the bulkhead 26
and each partition member 36, and the tip of the pipe is near the inlet 18, that is, the most upstream purification chamber 3.
It opens at the top of the first flow path 42 of No. 4.

A plurality of inspection tubes 60 are provided on the tank lid 16. Each inspection tube 60 is open to the ground and has a lid 62. Soil is piled up on the tank lid 16 to a predetermined thickness.

In operation, each air diffuser 50 and air lift pump 56 is supplied with air from an air source (not shown), such as a ground-based compressor. Air bubbles are ejected from each air diffuser pipe 50, and the air bubbles rise within the contact body 48, giving upward force to the wastewater. As a result, the dirty water at the bottom of each purification chamber 34 mixes with the air bubbles and moves up the second flow path 44 together with the air bubbles. Further, the air supplied to the air lift pump 56 rises inside the air lift pump, and thereby the dirty water at the bottom of the second chamber 24 is returned to the vicinity of the inlet 18 through the pipe 58.

The wastewater that has flowed into the septic tank 12 from the inlet 18 flows from above to below in the first channel 42 of the most upstream septic chamber 34 . The wastewater that has reached the bottom of the purification chamber 34 moves up the second flow path 44 while contacting the contact body 48 together with bubbles ejected from the aeration pipe 50 . As a result, the microorganisms attached to the contact body 48 are activated, and when the wastewater passes through the contact body 48, the microorganisms decompose organic matter, that is, sludge, and the wastewater is purified.

The wastewater that has flowed to the upper part of the second flow path 44 of the purification chamber 34 at the most upstream side flows through the first and second flow paths 42 and 4.
4 is partitioned off by the flow path defining member 40, it reliably passes through the contact body 48 and is reliably subjected to the purifying action of the microorganisms attached to the contact body.

The wastewater in the upper part of the second flow path 44 of the most upstream purification chamber 34 flows out from the weir 38 to the next purification chamber 34 when the water level in the purification chamber reaches the level of the weir 38 or higher. The wastewater that has flowed into the purification chamber 34 flows through the first flow path 42 from above to below, as in the purification chamber upstream of the purification chamber, and then flows through the second flow path 44 from below to above. After being subjected to purification action again, the water flows out from the weir 38 to the next purification chamber.

The sewage that has flowed into the septic tank 12 in this way passes through each of the septic chambers 34 in turn.
4 contact bodies 48, thereby undergoing a purification action in each purification chamber. When the water level in the most downstream purification chamber 34 is equal to or higher than the height level of the outflow portion 28, the wastewater flowing to the upper part of the second flow path 44 of the purification chamber flows into the first
The liquid flows out from the pipe 30 through the second pipe 32 into the second chamber 24, and then flows downward in the downflow pipe 54 while being prevented from directly reaching the outlet 20 by the downflow pipe 46. Since the wastewater flowing out from the first chamber 22 to the second chamber 24 has passed through the plurality of contact bodies 48, it is highly purified.

The waste water in the second chamber 24 is removed by an air lift pump 56
If the water level in the second chamber 22 exceeds the level of the outlet 20, the wastewater in the second chamber 24 will be It flows out of the septic tank 12 from the outlet 20. Since the wastewater flowing out of the septic tank 12 is supernatant water, it is highly purified wastewater.

The wastewater that has been returned to the vicinity of the inlet 18 flows through the first chamber 22 again together with the wastewater that flows in from the inlet 18, during which time it is again subjected to the purifying action. The sewage in the septic tank 12 is reliably circulated within the septic tank 12 by the air lift pump 56 even when no sewage flows into the septic tank. For this reason, inlet 1
The wastewater flowing in from 8 is circulated through the septic tank 12 multiple times before flowing out from the outlet 20, and is highly purified.

Components that decompose slowly in the sewage settle at the bottom of the second chamber 24 and become sludge.
8 to the first flow path 42 of the most upstream purification chamber, and is subjected to a decomposition effect by flowing through the first chamber 22 again.

According to the sewage treatment device 10, the first and second chambers 22 and 24 are partitioned by the partition wall 26, and the first chamber is divided into the first flow path 42 and the second flow path 44 by the flow path defining member 40. Since the contact body 48 is arranged in the second flow path 44, the wastewater flowing from the first chamber 22 to the second chamber 24 reliably passes through the contact body 48.

According to the sewage treatment device 10, the septic tank 12
Even if the amount of water in the second chamber 24 decreases, the wastewater in the second chamber 24 is returned to the first chamber 22, so the water level in the second chamber 24 decreases, but the water level in the first chamber 22 remains unchanged. Does not decrease. Therefore, the refluxed wastewater is transferred to the contact body 48.
The contact body 48 is not exposed to air, and the microorganisms attached to the contact body are not killed.

According to the sewage treatment apparatus 10, the first chamber 22 is further divided into a plurality of purification chambers 34 by the partition member 36, and each purification chamber is provided with a contact body 48 and an aeration pipe 5.
0 is arranged, the waste water passes through a plurality of contact bodies 48 while flowing in the first chamber 22, so that the waste water is purified to a higher degree.

Through experiments, the inventor has found that the capacity of the septic tank 12 should be about three-quarters of the daily average amount of sewage, and that it is necessary and sufficient to maintain the amount of circulating water at around 20 times the amount of raw water. I got to know.

Assuming the average amount of sewage per day is ^10m3 , the capacity is
The amount of wastewater circulated in a 7.5m ³ (10m ³ × 3/4) septic tank is 200m ³ (10m ³ × 20). This circulation is performed by the air lift pump 56, and the above-mentioned circulation amount is achieved by setting the inner diameter of the cylinder of the air lift pump to 50 mm and setting the amount of air supplied to the air lift pump at 0.16 m ³ per minute. . Expressing this as a formula, 0.16m ³ × 1440 = 230.4m ³ > 200m ³ . Note that 1440 is the number of minutes in a day, i.e. 24
×60.

If the average amount of sewage per day is ^50m3 , the capacity of the septic tank should be 38m3, and the inner diameter of the air lift pump cylinder should be ^38m3 .
125 mm and the air supply rate is 0.8 m ³ per minute, a circulation volume of 1150 m ³ can be obtained. Also,
If the average amount of sewage per day is 100 m ³ , a circulation volume of 2300 m ³ can be obtained by using a septic tank with a capacity of 75 m ³ and two air lift pumps with a cylinder inner diameter of 125 mm.

According to experiments, when the BOD value of wastewater flowing into the septic tank 12 from the inlet 18 is 180 to 200 ppm,
The BOD value of wastewater flowing out from outlet 20 is 20ppm
It was below.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of the sewage treatment apparatus of the present invention, FIG. 2 is a sectional view taken along line 2-2 in FIG. 1, and FIG. 3 is a sectional view taken along line 2-2 in FIG. FIG. 3 is a cross-sectional view taken along line 3; 10: Sewage treatment equipment, 12: Septic tank, 18: Inlet, 20: Outlet, 22: First chamber, 24: Second chamber, 26: Partition wall (first partition means), 28:
Outflow section, 30, 32, 54, 58: pipe, 36: partition member (second partitioning means), 38: weir, 40:
Flow path defining member (flow path defining means), 42: first flow path, 44: second flow path, 48: contact body, 50: aeration pipe, 56: air lift pump.

Claims (1)

[Scope of Claims] 1. A septic tank having an inlet and an outlet for sewage; a first chamber in the septic tank that communicates with the inlet; and a first chamber that communicates with the outlet and flows out from the first chamber. a first partitioning means for partitioning into a second chamber for receiving sewage; and a first partitioning means disposed above the first partitioning means for allowing the sewage in the first chamber to flow out into the second chamber. 1 outflow means; and the first outflow means;
a second partitioning means for partitioning the room into a plurality of purification chambers through which the wastewater passes sequentially; a second outflow means for allowing the wastewater to flow out; a contact means disposed in each of the purification chambers at a position spaced upward from the bottom thereof and for bringing the wastewater into contact with purifying microorganisms; and an aeration means disposed below the contacting means so as to blow out air toward the contacting means, and each of the purification chambers is provided with a flow path regulating means disposed within the purification chambers to prevent sewage from flowing into the purification chamber. a first flow path that causes the wastewater to flow from the upper part of the purification chamber to the lower part thereof, and a second flow path that causes the wastewater flowing out from the lower part of the first flow path to flow from the lower part of the purification chamber to the upper part thereof. A contact type sewage treatment apparatus, wherein the contact means is arranged in the second flow path. 2. The first outflow means communicates with a first pipe extending laterally through the first chamber and having a plurality of holes, and the first outflow means communicates with the first pipe and connects the partitioning means with the first pipe.
2. The contact type sewage treatment apparatus according to claim 1, further comprising a second pipe penetrating from the side of the chamber to the side of the second chamber. 3. The second outflow means includes a weir fitted into the second partition means so as to penetrate therethrough.
A contact type sewage treatment device according to claim 1. 4. A septic tank having an inlet and an outlet for sewage, a first chamber communicating with the inlet and a second chamber communicating with the outlet and receiving the sewage flowing out from the first chamber. a first partitioning means for partitioning the first room into a chamber, and a first outflow means disposed above the first partitioning means and allowing wastewater in the first room to flow out into the second chamber; Said first
a second partition means for partitioning the interior of the room into a plurality of purification chambers through which the wastewater passes sequentially; a second outflow means for allowing the wastewater to flow out; a contact means disposed within each of the purification chambers at a position spaced apart from the bottom thereof and for bringing the wastewater into contact with purifying microorganisms; an aeration means disposed below the contacting means to blow out air toward the contacting means; and sewage at the bottom of the second chamber is recycled to the vicinity of the inlet of the first chamber. and a reflux means for causing the
Each of the purification chambers has a first flow path through which wastewater flows from the upper part of the purification chamber to the lower part thereof by a flow path regulating means disposed in the purification chamber, and a flow path through which wastewater flows out from the lower part of the first flow path. and a second channel for causing wastewater to flow from a lower part of the purification chamber to an upper part thereof, and the contacting means is disposed in the second channel. 5. The contact type according to claim 4, wherein the second chamber is provided with means for guiding the wastewater flowing from the first chamber to the bottom of the second chamber. Sewage treatment equipment. 6. The circulation means includes an air lift pump that raises the waste water, and a pipe that makes the waste water raised by the air lift pump flow back into the first flow path of the first chamber that communicates with the inlet. , a contact type sewage treatment device according to claim 4.