JPH05285486A - Purifying tank - Google Patents

Abstract

PURPOSE:To enhance the backwashing effect of the aeration tank in a purifying tank purifying sewage generated in each house. CONSTITUTION:A purifying tank consists of a lowermost sedimentation tank 1 receiving the precipitate in sewage, a middle aeration tank 2 having filtering effect using small tubes composed of a synthetic resin material as a filter medium 14 and an uppermost air tank having a sewage inflow pipe 16 and a fresh water discharge pipe 17 arranged thereto and a backwashing pipe 9 washing the filter medium by the flow reverse to aeration water flow is provided to the boundary of the sedimentation tank 1 and the aeration tank 2 and at least a second backwashing pipe 10 is provided to the middle stage of the aeration tank.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention, when purifying wastewater such as human waste and wastewater, uses a small bottle made of a synthetic resin material or the like as a purification filter material in the aeration tank, and lays this filter material freely and aerates it. The present invention relates to a septic tank capable of improving the effect and significantly promoting the sewage purification function.

[0002]

2. Description of the Related Art Conventionally, in areas where sewerage is not complete, small-scale septic tanks are being used in order to deal with water quality regulations, environmental protection issues such as odors, and political issues such as water rights. Such a device mainly comprises a filtration means having a physical means using a filtration material and a biological means using an organic substance-decomposing bacterium. In particular, in order to maintain the processing capacity of this filtering means above a predetermined level, as a filtering material, an inorganic material such as gravel, activated carbon, charcoal, etc. or cement, fly ash, a molded product made of porous ceramics, or a synthetic resin. Various organic materials such as organic materials are used.

In addition, an inorganic material having a spherical shape or a nearly spherical shape is used to smoothen the movement of the filter material by the aeration air for replacing old and new aerobic microorganisms that attach to the filter material. Used. Further, in order to clean this filtering means and to activate various microorganisms to purify water, the air concentration in the aeration tank is increased by increasing the oxygen concentration in the water by using a diffuser tube or a backwash tube. The oxygen concentration is maintained at various values, such as high and low, to maintain the survival of various microorganisms and to purify and activate wastewater by virtue of the survival function of the microorganisms.

There is a so-called sewage purification tank of the so-called Ishii type water circulation system of the activated sludge method that satisfies these conditions. (Isao Ishii, Kunihiro Yamada, "Sewer Revolution" Fujiwara Shoten) This sewage purification tank is the first septic tank in order from the sewage inlets such as night soil, kitchen water, laundry drain, bath water, etc.
Second septic tank, preliminary filtration tank, flow rate adjustment device, first aeration tank,
The system is composed of a second aeration tank, a third treatment tank, a precipitation tank, a disinfection tank, a precipitation tank, and a pump in that order. Of these, a preliminary filtration tank using a Yakult container-shaped waste container with the bottom cut off as the above-mentioned filtering material, a flow rate adjusting device, a first aeration tank,
The second aeration tank and the third treatment tank are particularly characteristic.

The small bottle body of the Yakult waste container used as the filter material is obtained by cutting the bottom of the waste container. The so-called activated sludge method is used to propagate the microorganisms and to keep the propagated microorganisms healthy. It excels in satisfying the requirements. In other words, oxygen is blown into the sewage to aerate it,
The concentration of oxygen concentration in the wastewater can surely exist due to the undulations of the Yakult container, and it is possible to maintain a state in which many kinds of microorganisms can survive there.

[0006] This filter material is spread, and further, a tubular container-bonded filter material net is applied under the filter (filed as Japanese Patent Application No. 4-53058).
In the aeration tank equipped with, the appropriate air is constantly blown out by the diffuser tube to spout from the upper part of the draft tube and drop the water flow to the lower part to stimulate the circulating water flow upstream of the draft tube to supply an appropriate amount of oxygen. To do. Also, in order to settle the filth collected in the filter material in the settling tank, the entire filter material is washed by a powerful jet from the backwash pipe to drop the filth into the lower part.

[0007]

However, in such a conventional septic tank, since the backwash pipe is provided only in the lower portion of the tubular container joining filter material net in the lower portion of the aeration tank, The dirt inside and outside the filter that has accumulated due to the cleaning action for many years did not easily fall to the lower stage, and when a porous ceramic material was used for the filter, its eyes were clogged, and a Yakult-shaped synthetic resin material was used. Even in such a case, the inside and outside may be clogged with the waste, and the problem that the microbial viable volume for activation of the purification is reduced has arisen. Therefore, if backwashing with a backwashing pipe is frequently performed, it takes about 2 to 3 days to produce and propagate microorganisms, so that filth purification cannot be performed during that time, and the first rotting in the first stage in the active purification method is not possible. There was a problem that sewage had to be stored in the tank and the second septic tank, and an average of 1,000 liters of sewage per person per day could not be processed by a small septic tank. This is an issue for society as a whole that seeks to solve as much as possible the current environmental protection problem in which each household uses a small septic tank for purification treatment rather than in urban areas where sewerage facilities are developed.

[0008]

In order to solve the above-mentioned problems, in the septic tank of the present invention, the bottom settling tank for accommodating the sediment in the wastewater and a small bottle made of synthetic resin material and having no bottom A middle-stage aeration tank with a filtration effect using
It consists of an uppermost air tank that arranges an inflow pipe for sewage and a discharge pipe for fresh water, and provides a backwash pipe for washing the filter material at the boundary between the settling tank and the aeration tank in a reverse flow to the aeration water flow. At least a second backwash pipe is provided in the middle stage of the aeration tank. In addition, a filter material such as a ceramic material or a synthetic resin material is spread, and powerful air is jetted from the first backwash pipe provided in the lower stage of the aeration tank that purifies the sewage by the action of microorganisms in the filter material. It is a septic tank that collects the filth accumulated inside in a settling tank, and a second tank is installed in the middle stage of the aeration tank.
Is provided, and during backwashing, air is jetted from the second backwashing pipe and then air is jetted from the first backwashing pipe.

[0009]

In the septic tank of the present invention, a certain water flow is circulated in the aeration tank to breed various microorganisms to purify the sewage, but the filth produced during the purification should drop smoothly into the lower sedimentation tank. First, open the air valve of the second backwash pipe in the middle stage of the aeration tank to drop the filth accumulated in the upper part of the aeration tank toward the lower part, and then the air in the first backwash pipe of the lower stage of the aeration tank. The valve can be opened, and the dirt collected in the lower part of the aeration tank can be dropped further down to collect the dirt in the sedimentation tank.

Further, if only the air diffuser in the aeration tank and the backwashing in the lower backwash pipe do not reach the corners of the septic tank as the forward flow and the reverse flow of the water flow, the purification action deteriorates. However, the jet of air from the second backwash pipe backwashes all the inside and outside of the upper filter, which is particularly easy to move, and then the first backwash pipe activates the upper part of the aeration tank. Since the weight of the filter material and waste is lightened, the backwashing of the lower part of the aeration tank easily works in every corner, and reliable backwashing is possible, and overall The action can be maintained and a clear stream with a small BOD value can be obtained.

[0011]

Embodiments of the present invention will be described below with reference to FIG. 1 by taking a third processing tank as an example. In general, the third treatment tank is arranged next to the second aeration tank and has a role of feeding it to the next settling tank. Also, if the amount of wastewater treated is large,
It is set especially when it is not possible to obtain the desired fresh water with a low BOD value, when there is a room in the septic tank installation or cost, or when long-term system cleaning is not desired.

In FIG. 1, the septic tank container 20 has a size of about 4000 liters in the case of a family of 5 and is divided into upper, middle and lower three stages. Among them, 1 indicates a settling tank, and the specific gravity and shape of suspended solids contained in wastewater,
The sedimentation rate is determined by the density and viscosity of the liquid, but heavy objects, mainly sludge and food dregs, accumulate at the bottom of the sedimentation tank depending on the inflow rate and type of bath water, night soil, household wastewater, etc. from the inflow pipe. go. The sedimented heavy load is opened by opening the valve 193 from the blower pipe 19 and passing through the blower pipe 7 to the air lift 6
Air is injected into the tank, and the sediment thus deposited rises in the air lift 6 and is returned via the sediment discharge pipe 18 to the first septic tank which goes backward in the processing order (not shown). In addition, several columns for fixing the backwash pipe pedestal 11 and a settling tank cleaning pipe 13 for inserting a hose for taking out the waste that cannot be sent by the air lift 6 are also arranged in the settling tank.

Reference numeral 2 denotes an aeration tank, which supplies a certain amount of oxygen to the wastewater by the air diffused from the air diffuser 5 and increases the chances of contact between the pollutants and the activated sludge to increase the activated sludge. A large number of Yakult container-shaped vials 14 having an appropriate curved surface with a large contact area to prevent sedimentation are randomly filled. Its depth is about 1.5 m to 2 m. As the aeration effect of this aeration tank, activated sludge inhabiting a wide variety of bacteria, protozoa, etc. is affected by many factors such as nutrition, water temperature, dissolved oxygen, and PH, and changes in the composition of microbial groups in the activated sludge. At the same time, the organic matter in the sewage is used as a nutrient source for the biochemical reactions of oxidation and assimilation to grow, and the sewage is gradually purified.

The aeration tank 2 is provided with a wastewater inflow pipe 16 and a valve 1 for inflowing wastewater from a second aeration tank (not shown) in the preceding stage.
A rectangular draft tube 4 is provided in which 91 and 192 are opened and a backwash pipe 10 for backwashing through a blower pipe 23 and an air diffuser 5 for diffused air through a blower pipe 22 are housed inside to improve the air diffuser effect. .. Further, the cylindrical container-bonding filter material net 12 is a Yakult container-shaped small bottle, which is arranged in a horizontal direction in the same direction, and is gathered side by side in the same direction. It is manufactured by burying it in a liquid (fiber reinforced plastic material), taking it out, and drying it. The tubular container joining filter material net 12 is capable of mounting the filter material 14 on the upper portion thereof and is also mounted on the upper portion of the backwash pipe 9, and the large opening hole portion 24 is precipitated with the small opening hole portion 22 thereof on the aeration tank side. It is arranged on the tank side, and is placed so as to cover the entire circumference of the septic tank container 20 horizontally. Due to the construction of this cylindrical container joining filter screen 12, the large opening hole on the settling tank side allows the flow velocity of the sewage in the settling tank and the backwash pipe 9
The flow rate of sewage can be reduced and the sludge settling effect is improved.

Reference numeral 3 denotes an air tank, which comprises an inflow pipe 16 for introducing dirty water, an outflow pipe 17 for outflowing fresh water to the disinfecting layer, a blower pipe 7 for sending air to the air lift 6 of the settling tank 1, and an aeration tank 2. A blower tube 22 for sending air to the trachea 5, a blower tube 8 for sending air to the first backwash tube 9, a blower tube 23 for sending air to the second backwash tube 10, and further each blower tube 5, 7, 8, Valves 191 to 195 for controlling the opening and closing of air blow to the air conditioner 23 and its air amount, a main air blow pipe 19 for sending air, and the like are arranged. WL is a water level indicating the amount of fresh water. Here, the valve 195 adjusts the amount of air blown together with the valves 191 to 194 according to the degree of opening, a cleaning pipe 13 for cleaning the sludge of the settling tank 1 is provided, and the outflow of the outflow pipe 17 is the fresh water. When the water level (WL) becomes higher than the lower part of the outflow pipe 17, fresh water flows out. The fresh water is sent to the next disinfection tank, where it is chlorinated. The chlorine treatment kills the pathogenic bacteria that live in the treated water, thereby ensuring the sanitary safety of the treated water.

In the above-mentioned main structure, the valve 193 of the main blower pipe 19 is opened to blow air from the blower pipe 5 into the draft tube 4 through the blower pipe 22. Then,
Sewage is pushed up from inside the draft tube 4 and boiled out through its upper hole lower than WL. And the draft tube 4
When sewage enters through the lower opening of the lower part, water flow is circulated from the top to the bottom of the aeration tank 2 covered with the filter material. Therefore, the water flow circulates in and out of the aeration tank 2 through the filtering material net 15 to the inside and outside of the Yakult-shaped filtering material to create various environments from high oxygen concentration to low oxygen concentration, and microorganisms that survive there. By the action of, the aerobic and anaerobic treatments are simultaneously performed, and the sewage purification action is performed.

Next, when the cleaning time becomes long, the cleaning action inside the aeration tank is deteriorated, or the inside and outside of the filter material is clogged with filth, a reverse water flow in the opposite direction to the normal water flow is generated. Washing is done. First, the valves 192, 193, 19
5 is closed, valves 191 and 194 are opened, air is sent to the blower pipe 23, and air is ejected from openings of several mm arranged at several positions of the second backwash pipe 10 arranged in the middle stage of the aeration tank 2. To do. By doing so, the water flow rises to the upper part of the aeration tank 2 to clean the inside and outside of the filter material, flows down the inside of the draft tube 4 and passes through the cylindrical container joining filter material net 12 on the outer side thereof, and the Upstream outside. By this water circulation, the waste collected in the filter placed at the upper part passes through the draft tube 4 and collects in the settling tank 1.

Next, the valve 192 is opened to open the valve 19
1, 193 to 195 are closed, and air is sent to the blower pipe 7,
For example, every 15 cm of the first backwash pipe 9 assembled in a lattice shape or a blind shape, air is ejected from a hole having a small diameter, for example, 2 mm. By ejecting air from the backwash pipe 9 into the dirty water, the water flow in the aeration tank 2 is raised together with the air bubbles, and the inside of the draft tube 4 is made downstream. In particular, the lower filter material in the aeration tank 2 is made to dance, and the dirt that has not fallen during the backwash of the second backwash pipe 10 is successively dropped and settled in the settling tank 1. When this backwash is completed, the valve 192 is closed and the valve 193 is opened to start the purifying action of the aeration tank 2. At that time, the valve 193 is gradually opened to increase the water flow in the draft tube 4 due to air diffusion from the air diffusion pipe 5, and the aeration tank 2
Adjust so that the purifying action can be made constant while making the filter part of the downstream.

In the above embodiment, the second backwash pipe is provided at two places on both walls of the middle stage of the aeration tank 2, but when the septic tank container 20 is deeper or has a large area, It may be provided in multiple stages or in multiple locations. By doing so, it is possible to easily clean the dirt collected on the filter material made of the porous ceramic material or the synthetic resin material. However, it should be noted that if backwashing too much, it takes a long time for the microorganisms to reproduce, and the cleaning down time increases, which makes it unsuitable for cleaning domestic water. In addition, the draft tube 4 has a rectangular shape to optimize the water flow during purification and backwashing, and to keep the water flow constant in every corner of the septic tank to improve purification efficiency. 6, blower pipe 7
Etc. are provided to simplify the structure, but a round shape or a square shape may be used as long as it has such a shape.

Further, the embodiment of the septic tank according to the present invention has been described with reference to an example of a so-called tertiary treatment tank, but this may be a primary aeration tank, a secondary aeration tank or a preliminary filtration tank. The effect of can be fully exhibited. Further, the shape of the septic tank is not limited to the square shape, and a hopper type can be applied, and a deep layer aeration tank method can also be used. In the above example, the activated sludge method was used as an example. However, a digestion method using anaerobic microorganisms may be used, and the materials of the draft tube and backwash tube provided in this septic tank are PVC, PP,
Any semi-permanent one such as FRP may be used.

[0021]

In the septic tank of the present invention, since a plurality of backwash pipes are provided in the aeration tank, the filth collected in the upper part of the aeration tank is dropped to the lower part, and then the lower part of the aeration tank is reversed. By opening the air valve of the washing pipe and dropping the dirt accumulated in the lower part of the aeration tank further down, the dirt can be easily accumulated in the sedimentation tank early. In addition, air jets from multiple backwash pipes in the aeration tank backwash it to the inside and outside corners of the upper filter, which is especially easy to move. Since the weight of the filter material and waste is lightened, the backwashing of the lower part of the aeration tank easily works in every corner, and reliable backwashing is possible, and overall The action can be maintained and a clear stream with a small BOD value can be obtained.

[Brief description of drawings]

FIG. 1 is a drawing showing a septic tank according to the present invention.

[Explanation of symbols]

 1. Settling tank 2. Aeration tank 3. Air tank 4. Draft tube 9.10. Backwash pipe 7.22.23 Blower pipe 14. Filter material 19. Main blower pipe 191 to 195 valve

Claims (2)

[Claims] 1. A lowermost settling tank for accommodating precipitates in wastewater, a middle-stage aeration tank having a filtering effect and an aeration effect using a ceramic material, a synthetic resin material or the like as a filter material, and an inflow pipe for wastewater. A septic tank consisting of an uppermost air tank in which a discharge pipe for fresh water and the like are arranged, and a first backwash pipe for cleaning the filter material is provided at the boundary between the settling tank and the aeration tank, and the aeration tank. A septic tank characterized in that at least a second backwash pipe is provided in the middle stage. 2. A strong backflow pipe is provided from the first backwash pipe provided in the lower stage of the aeration tank for laying out a filter material such as a ceramic material or a synthetic resin material and purifying sewage by the action of microorganisms therein. Is a septic tank that collects the filth accumulated in the filter material into a settling tank below the aeration tank, and a second backwash pipe is provided in the middle stage of the aeration tank, and the second backwash is performed during backwash. A septic tank characterized by ejecting air from a pipe and then ejecting air from the first backwash pipe.