JP2649320B2 - Septic tank air diffuser - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air diffuser for a septic tank having a biofilm filtration tank.

[0002]

2. Description of the Related Art As shown in FIGS. 13 and 14, which are a vertical sectional view and a transverse sectional view of a conventional septic tank 1, a primary treated water receiving tank 2, a backwash drain tank 3, a biofilm filtration tank. 4. The treatment / purification tank 5 and the discharge pump tank 6 are connected in a cascade, and are installed on the floor (FL) below the ground (GL).
The septic tank 1 has a manhole 2 opened at the top.
6, the inside is inspected and monitored. The biofilm filtration tank 4 includes partition walls 30a, 30b, 30c,
30d, and a support tank 3 is defined therein.
A large number of porous ceramic carriers 23 (for example, hypermix, so-called granular foam glass, trade name, particle size: 2-10 mm), which are a plurality of filtration carriers, are filled through 2.

[0003] In particular, the biofilm filtration tank 4 has a support tank 32 on a floor plate filled with a porous ceramics carrier 23 to a predetermined level. Immediately below the support tank 32 of the biofilm filtration tank 4, an air diffusion pipe 22 and a backwash pipe 27 that diffuse into the filtration tank 4 are disposed horizontally with respect to the floor, and a diffusion pump ( (Not shown) and the backwash pump 18.

Next, a disinfection tank 15 a is provided at the outlet end of the treatment water tank 5, and disinfects the treated water with a disinfectant from the medicine tube 15 and sends the treated water to the discharge pump tank 6.

[0005] Finally, the treated water is discharged from the discharge pump tank 6 by the discharge pump 16 to the outside of the system through the discharge pipe 17.

[0006] In particular, the conventional air diffuser for a septic tank is shown in FIG.
5 and a two-way supply system as shown in FIG. 16 (FIG. 15) and 4
The direction supply method (FIG. 16) is adopted.

More specifically, as shown in FIG. 15, air diffusers 22b (for example, 13 mm in diameter) made of vinyl chloride are connected to each other by elbows 22c to form a square-shaped frame-shaped air diffuser 2.
2 is horizontal and connected to the diffuser 22b.
The air supply pipe 22a is connected to the blower 35 via an air supply valve 36, and air is supplied to the air diffusion pipe 22b from two directions as shown in a longitudinal sectional view of the air diffusion pipe 22b in FIG. Numerous diffuser holes 38 drilled downward in 22b
(For example, 3 mm diameter). At this time, low-pressure air (air pressure 0.1 to
0.3 Torr) is supplied, for example, at 120 liters / minute.

[0008] Further, as shown in FIG.
Are arranged horizontally to form a Japanese character, four air supply pipes 22a are connected to a blower 35 via an air supply valve 36, and air is supplied from four directions to the diffuser pipes 22 so that air is diffused. I do it.

[0009]

However, in such a conventional aeration device for a septic tank, even when the air diffuser is installed substantially horizontally with respect to the floor when the air diffuser is attached to the septic tank, the level of the air diffuser does not vary. If there is a slight difference in the air diffuser, no matter how much the air supply valve is opened and the amount of air diffused is finely adjusted, the air will flow to a higher level than the floor of the air diffuser (to the inclined side). A bias phenomenon occurred, and it was extremely difficult to perform uniform aeration over the entire biofilm filtration tank. In addition, there is a risk that contaminants such as dust may enter the air diffuser through the air holes opened downward.

In particular, when a diffuser used in a household septic tank is applied to a small-, medium-, or large-scale combined septic tank, the capacity of the biofilm filtration tank is large and the supply pressure of the diffused air is low. Even if there is some deviation in the horizontal direction of the air diffuser, there is a tendency for the amount of air diffused from the air diffuser to be non-uniform because of the low level of the installation machine foundation. for that reason,
Even at the site, fine adjustment of the level of the diffuser was required, and its installation was troublesome.

Therefore, the air diffuser of the present invention has been made in view of such problems, and uses a device in which the air diffuser is inclined in advance at the stage of installing the air diffuser in the septic tank. It is an object of the present invention to provide an air diffuser that can uniformly diffuse air throughout the biofilm filtration tank of the septic tank even if it is inclined, and that does not require fine adjustment on site.

[0012]

According to the present invention, in a septic tank having a biofilm filtration tank, the biofilm filtration tank is divided into a plurality of blocks, and an air diffuser is disposed in each block. The present invention relates to an air diffuser for a septic tank, which is installed in advance with an upward slope such that an air supply port is on a lower side in an axial direction.

[0013]

When air is supplied from the air supply port to the diffuser tube which is installed with a gradient upward, the inclination at the time of installation is eliminated and uniform air is diffused from the diffuser tube to the entire surface of the biofilm filtration tank.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a combined type septic tank according to the present invention.

As schematically shown in FIG. 1, a septic tank 1 to which the air diffuser of the present invention is applied has a Y-Y 'direction (axially).
From the inflow side of the raw water, the first treated water receiving tank 2, the backwash drainage tank 3 via the primary treated water receiving tank 2, the partition wall 2a, the biofilm filtration tank 4 via the partition wall 30c, the treated water tank 5 via the partition wall 30d, and the like. The treatment water tank 6 is configured to be connected in a cascade through a partition wall 5a.

In particular, the biofilm filtration tank 4 is defined by partitions 30a, 30b, 30c, and 30d as shown in the center of FIG. 1 and in the YY 'direction (axial direction, direction) of flow of the raw water, X-X 'direction (radial direction) is several divided as 1 ₁ × 1 ₂ virtual blocks (hatched portion), diffusing pipe air supply valve of the air diffuser 22 to the respective blocks 36, respectively. A blower 35 is connected to the air diffuser so that air for air diffusion can be supplied to the air diffuser. In this case, the unit block dividing the biofilm filtration tank 4 is Ma
x. _{(1 1 = 600mm, 1 2} = 600mm and, aeration tube of the air blowing opening (aeration pores) is upward, the hole diameter as 2 mm, blowing capacity of the blower 35, the aeration intensity H is 2~7Nm ³ / ^{m 3} H. Further, here, the number of holes n (pieces) of the air outlet opening in the diffuser is:

[0017]

(Equation 1) Is set as

Here, d ₁ : the inner diameter of the main air supply pipe d ₂ : the inner diameter of the air outlet C: the coefficient is 0.4 to 0.9.

In particular, in order to determine the design specifications of the air diffuser of the present invention, the inventor conducted an air diffusion experiment in a pool.

In this air diffusion experiment, an air diffusion device 22 as shown in FIGS. 2 and 3 was used. The air diffuser 22 is constructed by assembling a diffuser tube 22b in a letter shape via an elbow 22c, and air is directed downward at a right angle to the diffuser tube 22b at one end in the XX ′ direction (radial direction of the biofilm filtration tank). The supply pipe 22a was connected. Then, as shown in FIG. 3 in particular, the air diffuser pipe 22b is connected to the air supply pipe 22a from the horizontal plane by θ (+), θ
The air outlet (diffusing hole) was set so as to be inclined upward or downward. Here, the diameter d of the air diffuser 22b is 13 to 3
0mm, air outlet size (2mm, 3mm diameter)
Air was supplied from the blower at 140 liter / min, and the maximum inclination angle θ of the air diffuser tube 22b capable of uniformly diffusing air was determined by an experiment in this pool.

The results of this pool experiment are shown in FIG. 4 as the results of the aeration experiment. That is, the horizontal axis of this graph shows the diameter of the diffuser tube (mm), the diameter of the air outlet (2 mm, 3 mm) and its direction (upward, downward), and the vertical axis shows the inclination angle θ from the horizontal plane. According to the experimental results, it was found that the inclination angle θ can be increased regardless of the diameter of the air diffuser when the air outlet is 2 mm in diameter and the direction of the air outlet is upward from the horizontal plane. That is, since θ can be made large, it has been proved that a deviation (inclination) can be absorbed at the time of construction and at the time of installation of the air diffuser, and uniform air can be diffused without fine adjustment at the time of installation.

From the experimental results, as shown in FIG. 5, in the air diffuser 22 of the present invention, the air diffuser 22b is directed upward (θ (+)) from the horizontal plane to the vertical air supply pipe 22a via the elbow 22c. (Inclination degree of ± 1/100), the diameter of the air outlet is set to 2 mm, and the air outlet is set upward so that uniform air diffusion is performed. On the contrary, in this case, as shown in FIG.
It is not advisable to set the inclination at (−)) and make the direction of the air outlet downward.

In particular, in the case of a 50-person tank, for example, the air diffuser 22 of the present invention is configured in the shape of a letter and divided in the XX 'direction (for example, three blocks) as shown in FIG. The blocks are constructed by connecting the diffuser pipes 22b with elbows 22c, and the air supply pipes 22a are arranged in the respective blocks along the air supply pipes and connected to the blowers 35 via the air supply valves 36 to supply air for diffusion. It is supplied to the air diffuser 22b.

Then, as shown in FIG.
The air diffuser tube 22b is preset with a gradient of, for example, θ = 0.6 ° upward (θ (+)) from the horizontal plane via the elbow 22c so that the supply end of 2a is on the lower side. Due to this inclination θ, deviation during normal installation (± 1/200)
Is absorbed and does not affect uniform air diffusion. In particular, as shown in FIG.
0 to 25 mm), for example, 52 air outlets 38 (2 mm diameter) are formed upward, and a dust fall prevention plate (eave) 37 disposed immediately above the air outlets 38 prevents dust and the like. Infiltration of contaminants into the air diffuser 22b is prevented.

When the air diffuser 22 of the present invention thus constructed is installed in the septic tank 1, the deviation from the horizontal plane in the YY 'direction (axial direction) is caused by the air diffuser pipe 22 being directed upward from the horizontal plane in advance. The slope is about 1/100 of that, so even if there is a deviation of about ± 1/200, this deviation is absorbed by the previous 1/100 gradient, and the air is uniformly distributed in the biofilm filtration tank. 4 is diffused over the entire surface. The deviation in the XX 'direction (radial direction of the biofilm filtration tank) is corrected by adjusting the air supply amount by manually opening and closing the air supply valves 36 individually.

That is, as shown in FIG.
The amount of air diffused in the direction X-X '
The opening degree of the air supply valve 36 arranged in 2a is adjusted, and the amount of air diffusion in the YY 'direction is set to a preset angle (0.5 to 0.5) as shown in FIG. 10 °)
When installing in the septic tank 1 so that the air supply port (end) of the air supply pipe 22a is in the lower side in advance in the air diffuser pipe 22b.
It is set with a tilt of, for example, θ ₀ = 1/200 in the −Y ′ direction. Thereby, even if the horizontal error of the inclination of 1/200 is θ = ± 0.3 °, uniform air diffusion can be achieved over the entire biofilm filtration tank.

[0027]

As described above, the air diffuser for a septic tank according to the present invention divides the biofilm filtration tank into a plurality of blocks, and installs a diffuser pipe in each block with an upward gradient as described above. Even if the deviation is in the degree of horizontal installation of the air diffuser, uniform air diffusion is performed over the entire biofilm filtration tank. Also,
Fine adjustment of the level at the installation site is not required.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a septic tank to which an air diffuser of the present invention is applied, particularly showing an air piping system to the air diffuser.

FIG. 2 is a plan view of an air diffuser used in an air diffusion experiment of the air diffuser shown in FIG.

FIG. 3 is a front view of the air diffuser as viewed from the direction of arrows III-III in FIG. 2;

FIG. 4 is a graph showing the results of an air diffusion experiment using the air diffusion tube shown in FIG. 2;

FIG. 5 is a schematic view showing a preset angle of the experimental air diffuser shown in FIG. 2;

FIG. 6 is a schematic diagram showing another set angle of the experimental air diffuser shown in FIG. 2;

FIG. 7 is a schematic diagram showing an arrangement of diffuser tubes of the diffuser of the present invention.

8 is a front view of the air diffuser shown in FIG. 7 as viewed from the direction of arrows VIII-VIII.

FIG. 9 is a vertical sectional view of an air diffusion tube and a dust fall prevention plate of the air diffusion device shown in FIG. 7;

FIG. 10 is a schematic diagram showing adjustment of the amount of air diffused by a manual valve of the air diffuser of the present invention.

FIG. 11 is a schematic diagram showing adjustment of the amount of air diffusion by a preset angle in the XX ′ direction of the air diffusion device of the present invention.

FIG. 12 is a schematic diagram showing adjustment of the amount of air diffusion by a preset angle in the YY ′ direction of the air diffusion device of the present invention.

FIG. 13 is a longitudinal sectional view of a septic tank using a conventional biofilm filtration tank.

14 is a sectional view of the septic tank shown in FIG. 13 taken along the line XIV-XIV.

FIG. 15 is a schematic diagram showing a method of supplying air to the air diffuser of the conventional septic tank shown in FIG.

FIG. 16 is a schematic diagram showing a method of supplying air to the air diffuser of the septic tank shown in FIG.

17 is a cross-sectional view of a diffuser tube of the diffuser of the septic tank shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Septic tank 2 Primary treatment water receiving tank 3 Backwash drainage tank 4 Biofilm filtration tank 5 Treatment water tank 6 Discharge pump tank 7 Introductory tube 8 Discharge plate 9 Discharge port 10 Discharge port 12 Intermittent metering pump 16 Discharge pump 17 Discharge pipe 18 Backwash pump 32 Support layer 36 Air supply valve

Claims (6)

(57) [Claims] 1. A septic tank having a biofilm filtration tank, wherein the biofilm filtration tank is divided into a plurality of blocks, and an air diffuser is provided in each block. A septic tank air diffuser installed with an upward slope with the mouth facing down. 2. The air diffuser for a septic tank according to claim 1, wherein the air diffuser has a large number of upward air outlets. 3. The method according to claim 1, wherein said upward slope is 0.5 with respect to a horizontal plane.
The air diffuser for a septic tank according to claim 1, wherein the temperature is 10 to 10 degrees. 4. The air diffuser for a septic tank according to claim 1, wherein an air supply valve is provided in each of said air diffusers so that the amount of air supplied to said air diffusers can be adjusted independently. 5. The air diffuser for a septic tank according to claim 1, wherein the diameter of the air outlet is 2 mm. 6. The air diffuser for a septic tank according to claim 2, wherein an eave is provided above the air outlet.