JPH02222784A - Septic tank having air heating section for aeration - Google Patents

Abstract

PURPOSE:To maintain the activity of aerobic bacteria by providing an air heating section on an air feed side to supply air to an aerator disposed in an aerobic treatment chamber and operating this heating section when the temp. of treated water falls down to 10 to 15 deg.C. CONSTITUTION:The sewage flowing in from a discharge pipe D passes the 1st chamber a1, 2nd chamber a2 of an anaerobic treatment chamber C where the org. matter is decomposed by anaerobic bacteria. The treated water flows into the aerobic treatment chamber a3. The air is blown into the treated water from an air diffusion pipe 13a of the aerator in this chamber and the water rises under the aeration. Nitrogen compds. are decomposed by the aerobic bacteria of activated sludge while the water falls in an aerobic filter bed 12. The treated water is released through a settling separating chamber a4 and a disinfecting chamber 18. The heater is provided on the air feed side of the air diffusion pipe 13b. The heater is operated when the temp. of the treated water in the septic tank A falls down to 10 to 15 deg.C. The temp. of the treated water in the aerobic treatment a3 is thereby increased and the activity of the aerobic bacteria is maintained. The cleaning capacity of the septic tank is thus well maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a septic tank equipped with an aeration air heating section.

(b) Conventional technology Traditionally, as a form of septic tank, Utility Model No. 63-45894
There are items listed in the issue.

That is, in the septic tank, as shown in FIG. 6, the septic tank main body 90 has a first IIJ! Temper treatment room 91
, a second anaerobic treatment chamber 92 into which the sewage treated anaerobically in the first anaerobic treatment chamber 91 flows, and an aerobic treatment chamber 92 into which the sewage further anaerobically treated in the second anaerobic treatment chamber 92 flows. It consists of a treatment chamber 93, a sedimentation separation chamber 94 into which wastewater aerobically treated in the aerobic treatment chamber 93 flows, and a disinfection chamber 95 into which the supernatant liquid separated in the sedimentation separation chamber 94 flows.

Further, aerobic treatment in the aerobic treatment chamber 93 is performed by blowing air into the aerobic filter bed 96 from an aeration device 97.

According to this septic tank, the first anaerobic treatment chamber 91
It is considered that anaerobic treatment can be performed in two stages in the first and second pneumatic treatment chambers 92, and then aerobic treatment can be performed to obtain clean final treated water.

(c) Problems to be Solved by the Invention However, such septic tanks still have the following problems to be solved.

That is, in winter, the temperature of the treated water in the aerobic treatment chamber 93 is considerably lower than in summer. Therefore, in the aerobic treatment chamber 93, the activity of aerobic bacteria that oxidizes ammonia nitrogen contained in the treated water to nitric acid and nitrite also decreases significantly, making it impossible to perform aerobic treatment effectively. This will result in a decrease in purification ability.

Furthermore, like the septic tank structure previously disclosed by the present applicant in Japanese Patent Application No. 62-214008, a septic tank in which a part of the treated water in the aerobic treatment chamber 93 is returned to the first anaerobic treatment chamber 91 is also available. , the temperature of the treated water in the first anaerobic treatment chamber 92 similarly decreases, the activity of anaerobic bacteria decreases, and the anaerobic
Sexual treatment could not be performed effectively, and the purification ability was reduced.

An object of the present invention is to provide a septic tank equipped with an aeration air heating section that can solve the above problems.

(d) Means for Solving the Problems The present invention comprises an anaerobic treatment chamber and an aerobic treatment chamber arranged side by side in the septic tank main body, and an aeration device arranged in the aerobic treatment chamber. The present invention relates to a septic tank equipped with an aeration air heating section, characterized in that the air heating section is provided on the air supply side that supplies air to an aeration device.

The present invention is also characterized in that, in the above configuration, the air heating section is operated only when the temperature of the treated water in the septic tank drops to below 10°C to 15°C or during winter. It has the following.

(e) Examples Hereinafter, the present invention will be specifically explained based on examples shown in the accompanying drawings.

In Figures 1 and 2, A indicates a domestic septic tank, and the septic tank A is composed of a septic tank body a and a lid, and is a pipe for discharging sewage from household toilets, kitchens, etc. It is placed in the middle of the road.

As shown in FIGS. 1 to 3, the septic tank main body a has a box-like shape with an open top.

By erecting partition walls 1, 2.3 at regular intervals in the longitudinal direction, the internal space is divided into a first chamber a1 and a second chamber aa forming an anaerobic treatment chamber C. , an aerobic treatment chamber a, and a sedimentation separation chamber a in which a disinfection chamber 18 is disposed.

Below, the configuration of each chamber will be explained in order starting from the configuration of anaerobic treatment chamber C. As shown in FIG. 1, anaerobic treatment chamber C
The first chamber a1 communicates with the downstream side of the sewage discharge pipe through an inlet 4 having a substantially horizontal T-shape, and the sewage flowing into the first chamber a from the sewage discharge pipe is connected to the downstream side of the sewage discharge pipe. (hereinafter referred to as “treated water”)
) can be allowed to flow in while being bent downward.

In addition, a baffle plate 25 is provided directly below the inlet 4 and is tilted downward toward the second chamber at to prevent wastewater flowing into the first chamber a from the inlet 4. , along the same baffle plate 25, and is made to fall into the center of a downward flow anaerobic filter bed 5, which will be described later. Note that 26 is a baffle plate stay for attaching the baffle plate 25 to the septic tank main body a.

In addition, as shown in FIG. 1, the first chamber a of the anaerobic treatment chamber C
A downward flow anaerobic filter bed 5 is disposed in the center of the filter 1 at a predetermined distance downward from the inlet 4.

The downward flow anaerobic filter bed 5 is attached to supports 6 and 6' that are fixed to the sides of the septic tank main body a and the first chamber a+N of the partition wall 1 with an interval in the vertical direction, respectively, in the upper and lower parts of the lattice-like structure. Filter media shelves 7 and 7' are stretched and supported, and a desired filter material to which anaerobic bacteria is attached is filled between upper and lower filter media tanks 7 and 7'.

As the filter medium, a filter medium formed from a synthetic resin or other material formed to significantly increase the surface area and porosity can be used.

As shown in FIG. 1, a second chamber a8, which is arranged in parallel with the first chamber a through a partition wall l, accommodates an upflow anaerobic filter bed 9 therein.

This upflow anaerobic filter bed 9 has the same structure as the above-mentioned downflow anaerobic filter bed 5, but has the first advantage in that the void ratio between the filter media is made smaller and the surface area is made larger. room a1
This is different from the downward flow anaerobic filter bed 5 disposed inside the filter.

Note that, like the downward flow anaerobic filter bed 5, the upward flow anaerobic filter bed 9 also has upper and lower filter media shelves 8, 8' and supports 8a, 8.
b is fixedly disposed in the center of the second chamber.

Next, to explain the treated water transfer structure for transferring the treated water from the first chamber a1 to the second chamber a, as shown in FIGS. 1 and 2, the first chamber a1 and the second chamber a are , completely partitions the area below the treated water level in the septic tank body a, and separates the first chamber a1 from the second chamber a! The advection of the treated water is carried out through first and second transfer pipes 10, which are installed along the sides of the first chamber, g@, and second chamber of the partition wall l, respectively.
．． It will be held throughout the 11th.

The first and second advection pipes 10.11 are as shown in FIG.
The cross section of each plate is formed into an abbreviated shape, and a single plate (10a, lla) is placed at a symmetrical position across the partition wall l, and one edge of the same plate (10a, lla) is closely attached to the side surface of the partition wall. At the same time, the other edge is brought into close contact with the inner surface of the side wall 20 of the septic tank body a, thereby forming a tube whose upper and lower ends are open above and below each filter bed 5.9.

In addition, in the partition wall 1 between the advection pipes to and tt, there is a substantially rectangular communication port 21 that reaches from above to a position slightly lower than the treated water level.
is cut out to connect the first advection pipe 10 of the first chamber a1 to the second chamber a.
The treated water can be transferred to the second advection pipe 11 of g.

The first and second advection pipes 10.11 are arranged in two sets on the left and right sides of the partition wall so as to be equidistant from the inlet 4, and the first chamber a, A pair of left and right communication ports 21 are also provided to communicate between the communication port 21 and the second chamber a.
A movable weir 30 is attached so as to be slidable in the vertical direction.

Furthermore, to explain the treated water transfer structure in detail with reference to FIG. 1, the first advection pipe 10 has a downward flow anaerobic filter bed 5
The inlet 10a extends upwardly through the first chamber a1, and its inlet 10a opens at the bottom of the first chamber a1, and its outlet 10b
is opened at the upper part of the first chamber a1 at the time-height position of the treated water level.

Therefore, the treated water that has been anaerobically treated through the downward flow anaerobic filter bed 5 is transferred upward through the first advection pipe IO and directly flows into the second advection pipe +1.

On the other hand, as shown in FIG. 1, the second advection pipe 11 extends downward through the upflow anaerobic filter bed 9, and connects its inlet IQa to the upper part of the second chamber a2. It is connected to the outlet 10b of the first advection tube 10, and its outlet 11a is opened to the bottom of the second chamber a.

Therefore, the treated water that has been anaerobically treated by passing through the downward flow anaerobic filter bed 5 is divided into the downward flow anaerobic filter bed 5 and the upward flow anaerobic filter bed 9.
It flows directly into the bottom of the second chamber a through the first advection pipe 10 and the second advection pipe 11 without being subjected to anaerobic treatment.

The inflowing treated water then flows upward through the upward flow anaerobic filter bed 9 to be subjected to the second anaerobic treatment, and then flows into the aerobic treatment chamber a, which will be described below. I will do it.

In the above configuration, the configuration of the movable weir 30 provided in the communication port 21 forming the connection between the first advection pipe IO and the second advection pipe 11 will be briefly explained as shown in FIGS. 2 and 3.
As shown in the figure, the movable weir 30 is formed into a rectangular plate shape slightly wider than the width of the communication port 21, and has a sawtooth upper edge 30a, and has a side wall of the septic tank main body a adjacent to the partition l. Guide rails 31 and 31 provided on the inner surface of the second advection tube 11 and the inner surface of the side wall of the second advection tube 11 facing the same inner surface, respectively.
'It is fitted inside so that it can slide up and down freely.

In addition, a tension bolt sliding groove 32 is formed in the center of the movable weir 30 in a vertical manner from the lower end to the center, and a slide tension bolt 33 is inserted through the sliding groove 32 and into the partition l. A nut 34 with a tension knob is hinged to the tip of the adjustment bolt 33 so that the tightening can be adjusted freely, and the movable weir 30 is slid and fixed up and down by adjusting the tightening of the nut 34, so that the vertical position can be adjusted. There is. Note that 35 is a fixed plate.

Therefore, when installing the septic tank A, if the septic tank A is installed tilting left and right with respect to the vertical direction, the left and right movable weirs 30 and 30 must be adjusted by sliding them in the vertical direction. Therefore, the first chamber a, the second chamber a2
The amount of wastewater passing through each communication port 21, 21 and overflowing the movable weir 30, 30 can be made uniform, and a good purification efficiency can be ensured.

Next, the configuration of the aerobic treatment chamber a will be explained.

First, with reference to FIG. 1, the second chamber a2 of the anaerobic treatment chamber C
The configuration for transferring treated water from the aerobic treatment chamber a to the second chamber ag and the aerobic treatment chamber a will be described.

The partition wall 2 in between completely partitions the area below the treated water level of the septic tank body a, and the advection of the treated water from the second chamber a2 to the aerobic treatment chamber a is carried out through the second chamber a2 of the partition wall 2. This is done by the third advection tube 16 provided on the side of the example.

The third advection pipe 16 is formed into a substantially U-shaped cross section with upper and lower ends open, and the opening edge of the U-shaped cross section is brought into close contact with the side surface of the partition wall 2 on the second chamber at side, and the lower end is formed into an upward flow anaerobic tube. A substantially rectangular advection port 16 is formed in the partition wall 2 to form a pipe body of a third advection pipe 16 that opens above the filter bed 9 and whose upper end opens above the treated water level.
A is opened to create a second chamber a.

and aerobic treatment chamber a are communicated with each other at the upper part of each chamber ag and a3.

Next, the internal structure of the aerobic treatment chamber a will be described with reference to FIGS. 1, 3, and 4.

As shown in FIG. 1, the aerobic treatment chamber a includes an aerobic filter bed 12, an aeration device 13, and an air lift pipe 1.
4 and a backwash pipe 15 are built in.

(The air lift pipe 14 constitutes a part of the partially treated water recirculation structure E, which will be described later, so it will be explained in the section where the structure is explained.) First, the aerobic filter bed 12 will be explained. , the aerobic filter bed 12 is for performing aerobic treatment in cooperation with the aeration system ff13, and in this embodiment, as shown in FIG. 1, the aerobic treatment chamber 9. A large number of string-like filter media 12b formed by attaching a large number of fibrous filter threads in a substantially tuft shape to a central string are supported on a frame 12a that is settled at a predetermined interval from the inner bottom surface in its width,
It is constructed by attaching aerobic bacteria to the string-like filter medium 12b.

In addition, as a filter medium of the aerobic filter bed 12, a string-like filter medium 12b
In addition, other shapes such as corrugated sheet or honeycomb filter media can also be used.

Next, the aeration device 13 will be explained with reference to FIGS. 1 and 4, including a second chamber a and an aerobic treatment chamber a.

A pair of air diffuser pipes 13b, 13b extend along the bottom surface of the septic tank main body a in the left and right width direction from the lower end of the air vertical pipe 13a vertically installed along the partition wall 2 between the septic tank bodies.
b, 13b is formed from a fully porous tube having a large number of air ejection holes 13d.

With this configuration, the vertical air pipe 13a and the air diffuser pipe 13b
, 13b can diffuse air into the aerobic treatment chamber a, and the activity of aerobic bacteria can be maintained.

In addition, as shown in FIG. 4, in the middle of the air pipe 13c, there is an air volume 81 joint part 50 for adjusting the amount of air supplied to the aeration pipe 13h, and an air volume 81 joint part 50 for adjusting the amount of air supplied to the aeration pipe 13h. A three-way ball valve 55 is provided that can supply air from the backwash pipe 13b to the backwash pipe 15, which will be described later.

The present invention is essentially characterized in that, in the configuration of the aeration device 13, an air heating section H is provided on the air supply side that supplies air to the aeration device 13.

That is, as shown in FIG. 4, the air piping 13c, which has one end connected to the pump device P, has an air heating section H in the middle thereof.
There are 8.

The form of the air heating section H is to use +11 solar heat.
Various methods are possible, such as using a water heater or a heater such as a burner, but in this embodiment, as shown in FIG. 4, an electric heater 80 is wound around the air pipe 13c. A power source 81 and an on/off switch 82 are installed in the electric circuit of the electric heater 80.

Further, in this embodiment, the opening/closing operation of the opening/closing switch 82 and the operation of the pump device P are controlled by the control device based on the detection output of the temperature change sensor 83 that detects the temperature of the treated water in the aerobic treatment chamber a. 84.

That is, the temperature of the treated water in the aerobic treatment chamber a3 is, for example, 1
When the temperature drops from 5°C to 10oC, the temperature sensor 83 outputs a detection output, and based on the detection output, control! The filling device 4 can close the on/off switch 82 to energize the electric heater 80, thereby heating the aeration air fed to the aeration device 13 by the pump device ytP.

Note that the open/close switch 82 may be manually closed without using the temperature sensor 83 in the winter when the temperature of the treated water in the aerobic treatment chamber a decreases.

Further, although the temperature sensor 83 that measures the water temperature is used, a temperature sensor that measures the outside air temperature may be used, or both may be used.

In this way, in this embodiment, when the temperature of the treated water in the aerobic treatment chamber a decreases, the aeration air sent to the aeration device 13 can be quickly heated, and the aerobic filter can be heated. The activity of aerobic bacteria in the bed 12 can be maintained, aerobic treatment can be performed effectively, and purification ability can be maintained all year round.

In addition, as shown in FIG. 1, convection guide plates 60 and 61 are arranged directly above the left and right air diffusers 13b, 13b near the treated water level, and each temporary convection guide plate 60.
．． 61 has its lower end fixed to the partition wall 2 by support members 62 and 63, and its middle part is curved upward in a convex shape so that its upper end is close to the treated water level.

Therefore, the convection of the treated water in the aerobic treatment chamber a by the air diffused from the air diffusers 13b, 13b can be promoted, and the supply of air to the aerobic bacteria can be promoted.

Moreover, a certain gap S13 is formed between the lower end of each convection guide plate 60.61 and the partition wall 2, so that solids in the treated water stay on each convection guide plate 60.61 and rot. This prevents this problem from occurring.

Next, explaining the backwash pipe 15, the backwash pipe 15 is used to periodically remove excess sludge adhering to the string-like filter media 12b in the aerobic filter bed 12 and to maintain the activity of aerobic bacteria. belongs to.

As shown in FIGS. 1 and 4, the backwash pipe 15 has a backwash vertical pipe 15b vertically installed along the partition wall 3 between the aerobic treatment chamber a and the sedimentation separation chamber 84, and has a vertical backwash pipe 15b at its lower end. , one end of an air jet pipe 15a disposed approximately horizontally below the aerobic filter bed 12 is connected for communication, while the upper end of the above-mentioned backwash vertical pipe 15b is connected,
It is constructed by supporting and communicating with the air pipe 13c in a cantilevered manner via a flexible vibrator 15c.

Next, a part of the treated water reflux structure for refluxing a part of the treated water in the aerobic treatment chamber a to the first chamber a of the anaerobic treatment chamber C will be described.

As shown in FIG. 1, in the aerobic treatment chamber, an air lift pipe 14 is disposed vertically along the partition wall 2.

As shown in FIGS. 1 and 5, the air lift pipe 14 has its lower end opened above one of the air diffuser pipes 13b, and its upper end is connected to a water collecting pipe located slightly above the treated water level. It penetrates the bottom of the cell 14a and opens slightly above the bottom.

On the other hand, the water collection basin 14a has a return vibe 1 that has passed through the partition wall 2.
The other end of the vibrator 14b is extended to the upper part of the first chamber a1, and the tip of the other end is bent downward to open below the level of the treated water. .

With this configuration, a part of the treated water in the aerobic treatment chamber a can be returned to the first chamber a of the anaerobic treatment chamber C by using air ejected from the air lift pipe 14.

In addition, as shown in FIG. 1, the return vibrator 14b located above the second chamber ai has a cutout opening 14F for cleaning the inside of the pipe, and a cutout opening 14F for measuring the amount of returned processed water. A recovery section 40 is provided in each case.

Furthermore, as shown in FIG. 5, the water collection basin 14a is formed in a substantially box shape with an open top surface, and is attached to the upper part of the partition wall 2 in a cantilever state so that the vertical sliding position can be adjusted freely. When viewed from above, the partition plate 14c is provided on the diagonal line, and the partition plate 1
A substantially rectangular water passage hole 14d is opened at the bottom of 4c, and the upper end of the air lift pipe 14 is opened at one side of the partition plate 4C,
The other side is communicated with the return pipe 14b.

Furthermore, a substantially rectangular overflow opening 14e is cut out from above on one side of the water collection basin 14a, and a triangular weir 14g for communicating with the return vibe 14b is selectively formed on the other side. ing.

In addition, from the aerobic treatment chamber a to the first chamber a of the anaerobic treatment chamber C
As shown in FIG. 5, the amount of return sewage returned to the tank 1 can be adjusted by the vertical sliding position 131 of the water collection basin 14a connected to the air lift pipe 14.

In Fig. 5, 14b is a slot for sliding, 14i is a mounting bolt, and 14j is a tightening bolt! The nut for section 11 is shown.

In the above configuration, the water collection basin 14a has an open top, but it can also be covered with a lid.

Next, the configuration of the precipitation separation chamber a, which is arranged in parallel with the aerobic treatment chamber aff via the partition wall 3, will be explained.

As shown in FIGS. 1 and 3, the sedimentation separation chamber a4 is formed between the partition wall 3 and the partition wall 22 of the disinfection chamber 18, and the final treated water that has been aerobically treated is stored in the aerobic treatment chamber a. This was installed to allow the sludge contained within the tank to settle out.

As shown in the figure, the bottom of the sedimentation separation chamber a4 is connected to the bottom of the aerobic treatment chamber a through a communication path n provided at the bottom of the partition wall 3, and the aerobically treated treated water is , will flow into the sedimentation separation chamber a through the communication passage n.

Next, with reference to FIG. 1, the configuration of the disinfection chamber 18 provided within the sedimentation separation chamber a will be described.

The disinfection chamber 18 is disposed above the sedimentation separation chamber a by a partition wall 22, and has a generally box-like shape with an open top and separated from the sedimentation separation chamber a4.

In addition, the disinfection chamber 18 has its -side surface brought into close contact with the inner surface of the side wall of the septic tank main body a, and communicates with the discharge port 17 protruding from the rear wall of the purified pMa.
c is set slightly lower than the treated water level.

Further, at a position slightly lower than the treated water level h' on the inner surface of the disinfection chamber 18, a drug section support 18a is provided protruding from the side wall of the disinfection chamber 18, and the support 18a allows the solid disinfectant to be inserted from above. The king of the drug cylinder 18b of the drug filling method is supported while being brought into contact with the treated water advected from the settling chamber a.

To explain the other configuration of the sedimentation separation chamber a4, in FIG. 1, reference numeral 19 indicates scum outflow prevention plates that are vertically opposed to each other and protrude from the partition wall 3 to the left and right sides of the disinfection chamber 18, respectively.

This scum outflow prevention plate 19 has its side surface in close contact with the disinfection chamber 18, its upper edge protruding above the treated water level, and its lower edge immersed below the treated water level, so that the scum floating on the treated water surface is settled. This prevents the scum floating on the surface of the treated water in the separation chamber a4 from advecting from the sedimentation separation chamber as to the disinfection chamber 1B.

Further, a communication path n formed between the lower edge of the partition wall 3 between the sedimentation separation chamber a4 and the aerobic treatment chamber a is provided with a predetermined distance from the inner bottom surface of the septic tank body a. In addition, the sedimentation separation chamber a has an inner bottom surface forming the communication passage n, which is sloped downward in the direction of the aerobic treatment chamber a, so that the aerobically treated treated water can be aerobically treated. chamber a, precipitation separation chamber a,
In addition to smoothing the flow of sludge into the sedimentation chamber a4, the sedimentation of the sludge in the sedimentation separation chamber a4 is also promoted.

Next, the structure of the lid placed on the upper part of the septic tank main body a will be explained.

As shown in Figures 1 and 2, the lid body is fixed to a flange a fixed to the upper edge of the septic tank body a via bolts (not shown) or adhesively bonded with synthetic resin. The upper opening of the septic tank main body a is closed, and large-diameter first and second manholes b are formed above the partition wall 1 of the septic tank main body a and above the aerobic treatment chamber a. b is provided so as to be openable and closable, and a small-diameter third manhole bff is provided above the drug cylinder 18b so as to be openable and closable.

Hereinafter, a method for purifying wastewater from a household toilet or kitchen using a septic tank having the above configuration will be described with reference to FIG. 1.

From the upstream side of the sewage discharge pipe through the inlet 4 to the first chamber a
The treated water flowing into the filter 1 and the organic substances contained in the treated water (components of water, carbohydrates, proteins, lipids, urea, etc.) pass through the downward anaerobic filter bed 5. It undergoes anaerobic decomposition by anaerobic bacteria adhering to the surface of the filter medium on the bed 5.

That is, first, the organic matter in the treated water is reduced to a low molecular weight by acid-producing bacteria and converted into acetic acid (CMffCOOI+) and propionic acid (
C)1. cHICOOH), etc., and then
Anaerobic bacteria such as methane bacteria decompose 1i9 acids to produce methane (C) and carbon dioxide (CO2), and release these gases outside of the septic tank A. Ammonia nitrogen (NR,
”-N) is produced.

Incidentally, coarse solids contained in the treated water that has passed through the downward flow anaerobic filter bed 5 settle at the bottom of the first chamber cap.

By performing such anaerobic treatment, organic matter can be effectively removed from the treated water, and as a result, the treated water after anaerobic treatment has 1. Ammonia nitrogen (N) 14
-N) and a small amount of untreated organic matter in the first chamber a.
It will be transferred from I to the second room a2.

That is, the treated water after the anaerobic treatment passes through the first transfer pipe 10 and the second transfer pipe 11, and is transferred to the lower part of the upward flow anaerobic filter bed 9 in the second chamber a2 by the same filter bed 9. It is transported directly without any anaerobic treatment.

Thereafter, while passing through the upflow anaerobic filter bed 9 from bottom to top, it again undergoes the same anaerobic decomposition as described above, further decomposing organic matter, and then ammonia nitrogen (Nu
The treated water containing untreated organic matter (no-N) and further untreated organic matter is transferred to the next aerobic treatment chamber a through the third advection pipe 16.

Therefore, in this embodiment, the second chamber a of the anaerobic treatment chamber C,
The treated water is subjected to anaerobic treatment in an upflow anaerobic filter bed 9.
By creating an upward flow that passes through the anaerobic filter bed from the bottom to the top, the flow rate can be made slower than when using a downward flow that passes through the anaerobic filter bed from the top to the bottom. ,
More undecomposed substances can be anchored in the filter bed, and anaerobic decomposition can be further promoted.

Therefore, in addition to the anaerobic treatment in the first chamber a, the anaerobic treatment in the entire anaerobic treatment chamber C can be performed efficiently and sufficiently to reduce the generation or residue of undecomposed organic matter as much as possible. .

In addition, the acid-producing bacteria and anaerobic bacteria in the above anaerobic treatment are
Although it is possible to wait for the growth of acid-producing bacteria or anaerobic bacteria that have entered the treated water from the environment before using them, it is preferable to inoculate with a proven and excellent starter strain.

In addition, the treated water that has been anaerobically treated in the first chamber a1 of the anaerobic treatment chamber C is directly sent to the bottom of the second chamber a.
Since the undecomposed substances are not sent to the upper part of the upflow anaerobic filter bed 9, undecomposed substances may remain in the upper part of the upflow anaerobic filter bed 9, and the undecomposed substances may be transferred from the second chamber a2 to the second chamber a,
It is possible to reliably prevent the water from flowing directly into the aerobic treatment chamber a, which is arranged in parallel with the aerobic treatment chamber a.

Next, to explain the purification process in the aerobic treatment chamber a3, inside the aerobic treatment chamber a, air is blown into the treated water from the diffuser pipe 13b of the 1-air device 13, and the oxygen in the air is removed. Ammonia nitrogen (NH,
-N) is oxidized and decomposed into nitrate nitrogen (No, --N) and nitrite nitrogen (NO! --N).

As for aerobic bacteria, it is preferable to inoculate proven seed bacteria as described above, and by attaching such aerobic bacteria to the aerobic filter bed 12, the aerobic bacteria will flow out and the bacterial concentration will decrease. I try not to have anything to do.

Furthermore, in this example, all of the treated water that has been subjected to the anaerobic treatment and aerobic treatment is not discharged as it is outside the septic tank A, but the treated water that is undergoing aerobic decomposition treatment in the aerobic treatment chamber a. A part of l'lf is lifted to the water collection +J) 14a arranged above the air lift pipe 14 by air from the aeration pipe 13b blown into the air lift pipe 14 from below, and the air and moisture are removed in the collection water tank 14a. h1, and then returned to the first chamber al via the return pipe 14c.

Therefore, when the treated water containing nitrate nitrogen (NO, --N) and nitrite nitrogen (No2--11) flows into the first chamber a1, the denitrifying bacteria present in the first chamber a1, Utilizing the oxygen of these inorganic compounds, the organic matter flowing into the first chamber a1 is decomposed to obtain energy for survival.

As a result, inorganic compounds are reduced to molecular nitrogen (N2
) and nitrous oxide (N, O), and the organic carbon is decomposed to become carbon dioxide (Co□), which is released outside of the septic tank A.

In this way, the decomposition treatment of organic matter in the first chamber a1,
It can be performed not only by anaerobic treatment but also by using partially refluxed water from aerobic treatment chamber a3 and denitrifying bacteria acting on it.

Therefore, it is possible to suppress the excessive increase in ammonia nitrogen (NH, -N) that occurs when performing anaerobic treatment only with anaerobic bacteria (this acts in the direction of suppressing the activity of anaerobic bacteria), In addition, this suppressive effect makes it possible to maintain the activity of anaerobic bacteria in a suitable state at all times,
The decomposition treatment of organic matter in the anaerobic treatment chamber C can be dramatically improved.

In addition, by improving the ability to decompose organic matter, it is possible to significantly reduce the amount of untreated organic matter contained in the treated water transferred from the anaerobic treatment chamber C to the aerobic treatment chamber A. The generation of sludge in the aerobic treatment chamber a caused by this can also be reduced as much as possible.

On the other hand, nitrate nitrogen (NOl--N) and nitrite nitrogen (NOx--N) in the treated water in the aerobic treatment room a3
In case of A, a part of the treated water is returned to the anaerobic treatment chamber C, and these ions are decomposed into molecular nitrogen (l) and nitrous oxide (NZO) by denitrifying bacteria, so it is possible to can be reduced.

In this way, the treated water that has undergone aerobic decomposition bypasses the lower part of the partition wall 3 and flows into the lower part of the sedimentation separation chamber a, so as to prevent the extremely hard solids remaining in the treated water from being precipitated. !
- The treated water flows into the disinfection chamber 18, is disinfected and sterilized by the solid disinfectant that gradually flows out from the chemical cylinder 18h, and is discharged from the outlet 17 to the downstream side of the treated water discharge pipe.

In addition, by making the sedimentation separation chamber a4 an upflow type, a sludge blanket is generated, and even small flocs with relatively light specific gravity can be collected.Furthermore, the inner bottom surface of the sedimentation separation chamber a4 can be subjected to aerobic treatment. It descends steeply in the direction of chamber a (by sloping it around, the sedimentation separation heat chamber a, and the settled sludge inside the aerobic treatment chamber a)
I am trying to move it to the bottom of ff.

In this way, the final treated water that is purified from the toilets, kitchens, etc. of the home and discharged to the downstream side of the treated water drainage pipe is processed in the aerobic treatment room a. Since the structure is such that part of the water is recycled, the BOD concentration and nitrogen concentration can be significantly reduced.

According to experiments conducted by the present applicant, the BOT concentration, etc. in the final treated water obtained by the septic tank A according to this example were as shown in the table below.

Note that the numerical values are expressed as average values.

Unit (mg/p3) As is clear from the table below, in the case of this example, the BODfi degree etc. can be significantly reduced compared to the conventional septic tank.

Also, the drops of sewage flowing into the anaerobic treatment chamber C are Q.

If the partial recirculation amount from the aerobic treatment chamber a to the anaerobic treatment chamber C is Ω, then the amount of treated water Q transferred from the anaerobic treatment chamber C to the aerobic treatment chamber A is Q. * = Q + +
Q! However, Q+ :Qt= 1 : 1~10
(optimally 1; 2 to 6) was found to be preferable.

By the way, since non-degradable solids such as synthetic fiber fragments, sand grains, and synthetic resin film fragments may be mixed in the initial inflow treated water, it is inevitable that each chamber of the septic tank a, that is, the first Room al, 2nd room 8I, aerobic treatment room a, solids that cannot be completely decomposed or peeled off! Sludge consisting of the remains of 111 Sono is deposited.

In this case, the first part of the lid. 2nd manhole bb! By opening the first and second advection pipes 10.11 to 1lfll, it is possible to easily insert vacuum hoses for sucking sludge into the bottoms of the first chamber a1 and the second chamber a2. I can do it,
Furthermore, by sucking up the sludge in the aerobic treatment chamber a, the sludge in the sedimentation separation chamber a is also sucked out at the same time. Also, the third
The medicine cylinder 18b can be easily replaced by opening the manhole b.

In addition, surplus sludge adheres to the aerobic filter bed 12, but by operating the three-way ball valve 55, the ejection pipe 1 of the backwash pipe 15
While blowing out air from 5a, the flexible vibe 15
The excess sludge can be reliably washed away by manually moving the ejection pipe 15a through the pipe c.

Furthermore, as described above, in this embodiment, when the temperature of the treated water in the aerobic treatment chamber a decreases, the aeration air sent to the aeration device 13 can be quickly heated. The activity of aerobic bacteria in the aerobic filter bed 12 can be maintained, aerobic treatment can be performed effectively, and purification ability can be maintained all year round.

(f) Actions and Effects As explained above, the present invention has the following effects.

■ An air heating unit is installed on the air supply side that supplies air to the aeration device, which prevents the temperature of the treated water in the aerobic treatment chamber from dropping below a certain temperature, and reduces the activity of aerobic bacteria. Can be maintained all year round. Therefore, aerobic treatment in the aerobic treatment chamber can be performed well throughout the year, and the purification ability of the septic tank can be improved.

(2) Energy saving can be achieved by operating the air heating section only in winter or based on a decrease in the water temperature in the septic tank.

■If a part of the treated water from the aerobic treatment room is returned to the anaerobic treatment room, the temperature of the treated water in the anaerobic treatment room will also increase, increasing the activity of anaerobic bacteria, and Anaerobic treatment in can also be maintained well.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional side view of a septic tank having an upflow anaerobic filter bed according to the present invention, Fig. 2 is a sectional view taken along line [-1] of Fig. FIG. 4 is a plan view of an aerobic treatment chamber, FIG. 5 is a perspective view of a water collection basin, and FIG. 6 is a conceptual diagram illustrating the configuration of a conventional septic tank. In the figure, A; septic tank C: anaerobic treatment chamber; Anaerobic filter bed 9: Upflow anaerobic filter bed 13: Aeration device Fig. 5

Claims (1)

[Claims] 1. An anaerobic treatment chamber (C) and an aerobic treatment chamber (a_3) are arranged side by side in the septic tank body (a), and aeration is carried out in the aerobic treatment chamber (a_3). The septic tank equipped with the device (13) is equipped with an aeration air heating section characterized in that an air heating section (H) is provided on the air supply side that supplies air to the aeration device (13). Septic tank. 2. The air heating unit (H) is activated when the temperature of the treated water in the septic tank (A) drops below 10°C to 15°C. A septic tank equipped with an air heating section for aeration. 3. A septic tank equipped with an aeration air heating section according to claim 1, wherein the air heating section (H) is operated only in winter.