JPS62163794A - Method and device for purifying sewage - Google Patents

Abstract

PURPOSE:To purify sewage with a high purifying power by circulating the sludge at the bottom part on the inlet side of a septic tank to the vicinity of the inlet side, aerating the fluidized sewage from the bottom part, and bringing the sewage into contact with a catalytic body. CONSTITUTION:In the catalytic aeration type purification of sewage utilizing aerobes, an air-lift pump 12 for returning sludge is provided in the vicinity of the vessel bottom immediately under a riser tube communicating with the outlet 4. The pump is communicated with a sludge returning pipe 13 and opened in a downcomer 5. The catalytic body 14 enriched in microbes is packed over the grid plate 2 in the vessel 1, and a diffuser pipe 15 for fluidizing sewage is furnished below the grid plate 2. Consequently, the sludge in the septic tank is allowed to flow at all times, aerated several times while being decomposed, and brought into contact with the catalytic body plural times. Accordingly, sewage can be highly purified with a high purifying power.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a method and apparatus for purifying wastewater, and in particular to a contact IQj pneumatic method suitable for purifying wastewater using aerobic microorganisms. The present invention relates to a method and apparatus for converting water into silt.

(Prior art) As one of the water purification devices, aerobic microorganisms
The contact body is placed in a septic tank so that the unpurified water passes through the contact body upward or from the direction F, and the sewage to be purified is transferred to the septic tank in the above-mentioned 79 Move the 11fr sewage from the water inlet side to the flow 1j[l side, diffuse aeration in the wastewater during this time, and when the 7 water passes through the contact body, the 11fr sewage is removed by the microorganisms. There is a purification device to purify it.

However, all conventional sewage purification devices have a structure in which sewage passes through one septic tank once, which means that the purification level is low because the sewage passes through one septic tank once, and the degree of purification is low. The flow rate of the septic tank becomes poor, and sludge in the sewage to be purified accumulates at the bottom of the septic tank, especially at the bottom near the outlet of the septic tank. 'jMud is the cause of lowering the degree of purification of sewage discharged from septic tanks.

(Object of the Invention) The present invention provides a sewage purification method and device that has high purification power, does not allow sludge to accumulate at the bottom of the septic tank on the outflow side, and highly purified sewage is discharged from the septic tank. I to do
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(Structure of the Invention) The sewage purification method of the present invention recirculates sludge present at the bottom on the side of the outlet of a septic tank having an inlet and an outlet of sewage to be purified to the vicinity of the inlet. During this time, the sewage flowing from the inflow 11 to the +'+f outflow 1' is aerated from the bottom of the treatment tank, and the sewage is brought into contact with a contact body.

The sewage purification device of the present invention has an inflow l1 and an outflow ``J'' of sewage to be purified, and a septic tank in which the sewage moves from the inlet to the outlet, and a flow path of the sewage in the septic tank. A contact body arranged at the bottom of the 11η outlet of the septic tank is forced to circulate near the inlet. An L stage is arranged at the bottom of the septic tank, and the sludge existing at the bottom of the 11η outlet side of the septic tank is forced to circulate back to the vicinity of the inlet. 11 Have the means to care for your father.

(Effects of the Invention) In the sewage purification method and device of the present invention, the sludge present at the bottom of the septic tank at the outlet side is recycled to the vicinity of the inlet l' and combined with the sewage to be purified that is supplied to the inlet. The water flows through the septic tank from the inlet 1 to the outlet. Therefore, the sludge in the septic tank constantly flows within one septic tank, is decomposed in one septic tank, is aerated multiple times, and comes into contact with the contact body multiple times. Therefore, according to the present invention, the purifying power is high, sludge does not accumulate on the bottom of the septic tank at the outlet side, and highly purified water is discharged from the septic tank.

(Example) Embodiments of the present invention shown in the drawings will be described below.

The purification apparatus shown in FIGS. 1 to 3 includes a septic tank buried underground. The septic tank has a box-shaped tank body l that opens upward.
and a tank lid 16 that closes the upper opening of the tank body, and has a rectangular front shape that is 2 to 3 times longer than the long side or the short side. A hole is bored in the tank 16. In the tank 161-, the holes are arranged at J'λ of about 250 mm. Inside the tank body 1, there is a fine lattice plate 2 of I-1.
The septic tank is stretched at a position separated from the bottom of the tank body 1 to the north by a height of about 1/4 of the height of the septic tank. At the upper part of one side wall of the tank body 1 facing opposite to each other in the direction of long hair, there is provided a 7at part [13] of the sewage to be purified, and in the Y part of the other side wall, there is provided an outflow of the purified sewage [- 14h' +9
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On the side of the inlet 3 in the tank body 1, there is disposed a downstream pipe 5 that communicates with the inflow port 13, and on the side of the outflow port 14 in the tank body 1, there is arranged a downstream pipe 5 that communicates with the outflow port D4. and a surface water introduction pipe 7 are arranged. Downstream pipe 5. Each of the riser pipe 6 and the introduction pipe 7 extends upward from the height of the grid/plate 2 within the tank body 1 and opens downward. The flow F pipe 5 has a first flow path through which sewage to be purified in the tank body 1 flows from the top to the bottom in the flow pipe 5, and a flow path through which the sewage flowing down the first flow path flows from the top to the top. It is divided into a second flow path and a second flow path.

An overflow pipe 8 is communicated with the upper part of the introduction pipe 7. The overflow pipe 8 extends from the introduction pipe 7 toward the longitudinal center of the tank body 1, and also has a plurality of water collection holes 9. An air lift pump 10 is provided at the upper part of the introduction pipe 7, and the ['i'4] of the air lift pump 10 is connected to the end of a circulation return pipe 11 installed at the upper part of the tank body 1. Circulation Return pipe 11
The other end opens 1-1 into the flow pipe 5.

An air lift pump 12 for returning sludge is installed at a position close to the bottom of the riser pipe 6, and the upper end of the air lift pump 12 is connected to the circulation return pipe 11 and a sludge return pipe installed in the V line. It is connected to one end of 13. The other end of the mud return pipe 13 opens into the downflow pipe 5.

In the area above the lattice plate 2 in the tank 1, a contact body 14 rich in microorganisms is filled in the entire area extending from the top of the Y-board 2 to the top of the tank 1. The contact body 14 needs to have a large contact area with the wastewater, and is preferably made of a synthetic resin formed in the form of loofah fibers, such as Hetimaron (trade name). An aeration pipe 15 for flowing sewage is arranged in the area below the r-board 2 in the tank body l. The air diffuser pipe 15 is installed at the bottom of the tank so as to be located on the F side of the contact body 14.

At the bottom of the downflow pipe 5 and the riser pipe 6, an above-ground opening pipe 17 having a lid made of cast iron is provided. The 11η cover of the ground-opening tube 17 is exposed above the ground. The bottom opening tube 17 is used for checking the circulation state of sewage and sludge in the septic tank, collecting undecomposable materials, replenishing microorganisms, and the like.

When the purifier is in operation, air is supplied to the air lift pump 10°12 and the diffuser pipe 15.

The air supplied to the air lift pump 10.
The air bubbles ejected from the contact member 14 pass through the contact member 14 and reach the contact point.

The sewage flowing into the tank body 1 from the inflow 1' 3 flows through the flow pipe 5.
It flows through the tank body 1 and reaches the tank bottom area in the F direction from the grid plate 2, and gradually diffuses to the tank bottom area 11η, but it cannot be directly supplied to the top surface of the contact body 14. do not have. For this reason,
Dirt does not accumulate on the contact body 14F.

The bubbles ejected from the air diffuser 15 ascend the second flow path in which the contact body 14 is arranged, and not only activate the aerobic microorganisms attached to the contact body, but also diffuse into the bottom area of the tank. The sewage is aerated to give it a rising force of 1π.

As a result, the wastewater undergoes an organic matter decomposition action, that is, a purification action, by the microorganisms attached to the contact body 14, while
It rises inside the contact body 14. The increased amount of sewage is transferred to the contact body 14
The water flows into the overflow pipe 8 from the water collection hole 9 at the upper part of the pipe, and flows through the introduction pipe 7.

The sewage that has flowed down in the introduction pipe 7 is raised from the lower part of the introduction pipe 7 by the air lift pump lO,
It is returned to the flow F pipe 5 via the circulation return pipe 11 while being aerated with zero air. The wastewater returned to the downflow pipe 5 is combined with the wastewater supplied to the inflow port 3, and flows down the inside of the downflow pipe 5 again. Therefore, even when sewage does not flow in from the inlet 3, the sewage in the preservation pot always flows. The water 71'j that has flown into the inlet 3 in this manner is circulated within the tank body 1 several times before flowing out from the outlet 4, and is highly purified.

Components contained in wastewater that are slow to decompose organic matter settle at the bottom of the tank and become sludge, which obstructs the circulation of water. Is this sludge easy to deposit in the tank J 戊 on the outflow side [-14]? Gere, 7
1) The mud is returned to the tow pipe 5 via the mud return pipe 13, and is then flowed through the tow pipe 5. Therefore, the degree of purification of the water flowing out from the outflow [-14] is improved.

Air supplied into the tank body 1 by the air lift pump 10.12 and the air diffuser 15 flows out into the atmosphere through a hole formed in the tank 16 and above the tank lid 16F. For this reason,
The odor inside the tank body 1 is absorbed onto the seed stone 16 and does not reach the atmosphere.

According to experiments, when the BOD value of the wastewater flowing in from the inlet 3 is 180 to 200 ppm, the wastewater coming out from stream 11-14 at 7Aε is purified to a BOD value of about 20 ppm, and this is purified by the Trend method. When connected to equipment, the water-absorbing material will not become clogged and will not interfere with water purification.

[Brief explanation of drawings]

Fig. 1 is a longitudinal section 1' showing an embodiment of the purification device of the present invention.
A, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG. 3 is a sectional view taken along line BB in FIG. 1. 1: Tank body of septic tank, 3: Inlet, 4 outlets, 5: Flow pipe, 12: Air lift pump, 13: Sludge return pipe, 14: Contact body,
15: Diffuser pipe. Agent B1 Rigami Nobuyuki Matsunaga Figure 1B Figure 3

Claims (4)

[Claims] (1) In a septic tank having an inlet and an outlet for sewage to be purified, the sludge existing at the bottom on the side of the outlet is circulated near the inlet, and during that time, the sludge is circulated from the inlet to the outlet. A sewage purification method characterized by aerating flowing sewage from the bottom of the treatment tank and bringing the sewage into contact with a contact body. (2) The sewage purification method according to claim (1), wherein the sludge is circulated near the inlet by an air lift pump. (3) A septic tank having an inlet and an outlet for sewage to be purified, in which the sewage moves from the inlet to the outlet, and a contact body disposed in the sewage flow path of the septic tank. , a means for forcibly circulating sludge existing at the bottom of the outflow port of the septic tank near the inlet; and a means disposed at the bottom of the septic tank for aerating the sewage. Purification device. (4) The circulation means is arranged near the outflow port in the septic tank, and includes an air lift pump extending upward from the bottom of the septic tank, one end communicating with the air lift pump, and the other end near the inflow port. The sewage purification device according to claim 3, further comprising a return pipe that opens to the sewage purifier.