KR100271932B1 - Waste water treatment equipment & method with the function of deodoring, antifoaming, intermittent aeration and intra circulation - Google Patents

Abstract

PURPOSE: Disclosed is an apparatus for treating wastewater with intermittent aeration device, defoaming device, and deodorizing device. When an air supplying valve (8) is opened, air is introduced in an air supplying pipe (6) by gushing wastewater by a pump (2). Thereby, mixture of air and water is sprayed into a reactor (1), so the reactor (1) come into aerobic condition. Also, odor supplied from a concentration tank or a dewatering tank is injected into the reactor (1) through the air supplying pipe (6) for deodorization by aerobic microorganisms. When the air supplying valve (8) is closed, the reactor (1) becomes anaerobic condition. The pump (2) is operated continuously, so suspension of solids is maintained. CONSTITUTION: The apparatus is characterized by comprising the follow parts: the reactor (1) equipped with the pump (2); a pipe (4) equipped with the pump (2); an ejector (5) equipped with the air supplying pipe (6); a main pipe (7) for supplying air equipped with the air supplying pipe (6); an air supplying valve (8), which is opened or closed automatically, equipped with the main pipe (7) for supplying air; and a pipe (23) for supplying odor from the concentration tank or the dewatering tank. The apparatus reduces operation cost by not installing additional defoaming or deodorizing devices.

Description

Wastewater treatment system and wastewater treatment method equipped with deodorization, defoaming, intermittent aeration and internal circulation

The present invention relates to a wastewater treatment apparatus and a treatment method, and more particularly, to a wastewater treatment apparatus and treatment method capable of efficiently removing nitrogen and phosphorus in sewage simultaneously and reducing facility and maintenance costs in sewage and wastewater treatment plants. It is about.

Pollutants in sewage are roughly divided into organic and nutrients, nitrogen and phosphorus, expressed in biochemical oxygen demand (BOD). Up to now, sewage treatment plants have been mainly treated with organic matter, and much of the nutrients nitrogen and phosphorus have not been removed, but have been discharged into rivers, lakes, or oceans.

If the sewage is discharged with nitrogen and phosphorus, it causes eutrophication in rivers and lakes, and if it enters the ocean, it can cause red tide. Severe eutrophication leads to odors and water pollution, as well as limited use of drinking water and waterways. Therefore, in order to prevent eutrophication of the water system as above, it is necessary to sufficiently remove nutrient nitrogen compounds or phosphates in the sewage treatment plant.

Nitrogen and phosphorus removal processes used in sewage treatment plants have a structure in which an anaerobic reactor that does not supply oxygen and an aerobic reactor that supplies oxygen are arranged separately. According to the characteristics of each reactor, the aerobic reactor converts organic nitrogen or ammonia nitrogen into nitrate nitrogen, and in the anaerobic reactor, the denitrification reaction in which nitrogen nitrate is reduced to nitrogen gas and released into the atmosphere is induced to release phosphorus from the sludge.

The phosphorus component thus released is overingested by the microorganisms in the aerobic reactor, and the microorganisms ingesting the phosphorus are removed through the excess activated sludge to obtain the treated water from which nitrogen and phosphorus are finally removed.

In the conventional nitrogen and phosphorus removal method, a number of anaerobic tanks, anoxic tanks, and aerobic tanks are separately separated and fixedly installed at a predetermined capacity, so that they lack the capacity to flexibly cope with changes in inflow water quality and inflow water. In addition, in order to inject the methanol into the electron donor for denitrification or to use organic matter in the sewage, the water of the nitrification tank has to be internally circulated to the denitrification tank in the previous stage of the nitrification tank. In case of injecting methanol, the chemical cost is large, and the internal circulation flow rate for using organic matter in the sewage is about 4 times greater than the treated flow rate. For example, in the case of a sewage treatment plant having a treatment capacity of 10.000m ³ / day, since the internal circulation flow rate is 40,000m ³ / day, a large pump facility is required, and thus a problem that requires a lot of pump facility costs, power costs, and maintenance costs has existed.

In order to solve this problem, an intermittent aeration method may be used to supply air intermittently to repeat anaerobic and aerobic conditions in one or two or more reactors. The intermittent aeration method repeats the aerobic state and oxygen-free anaerobic state where oxygen is supplied in the same reactor at a time interval, and in the same reactor, the air is blown into the aeration tank and stopped to repeat this anaerobic / aerobic state. Is repeated at the set time interval.

By applying the intermittent aeration method described above, the number of reaction tanks can be reduced compared to the conventional treatment process, thereby reducing the mechanical construction cost, power cost, and facility operation cost.In particular, unlike the conventional method in which the capacity of the reaction tanks such as anaerobic tank and aerobic tank is fixed By adjusting the intermittent aeration time, it is possible to obtain the same effect as changing the reaction tank capacity in the conventional method, and there is an advantage in that it can flexibly cope with changing conditions of the influent.

Although the intermittent aeration method has many advantages as described above, no clear device and method have been developed so far, and using the existing devices, it is inevitable to separate and install the abandoned paper and the mixing device. In more detail, when using a combination of conventional devices, as shown in FIG. 9, the air blower 102 and the diffuser 105 for supplying air to the aeration tank 101 are configured to stop the operation of the blower. In the aeration step, the stirring device 103, which is a mixing device that enables the suspended sludge to flow smoothly without settling on the bottom of the aeration tank, was required. If the above apparatus is installed separately from the blower device 102 and the stirring device 103, it is uneconomical in terms of facility cost and power cost, and also difficult to maintain.

In particular, when the stirring device 103 is composed of a water rotating body 104 that generates water flow, when the fluidized bed biofilm contact material is filled in the aeration tank in order to apply a biofilm method for attaching and growing microorganisms by a method of treating sewage, Since the biofilm contact material was damaged by colliding with the underwater rotating body 104 of the stirring device, it was possible to apply the fluidized bed biofilm method.

In addition, a large amount of foam is generated in the aeration process of injecting air in the aeration tank of the sewage and wastewater treatment plant. Such a large amount of foaming is mainly caused by surfactants such as soaps and detergents contained in raw water or microorganisms that generate bubbles such as rocardia, and bubbles are scattered around the treatment plant under severe foaming and windy weather conditions. To cause secondary pollution.

As a countermeasure against such foaming, a nozzle is installed on the surface of the reactor to calm bubbles generated excessively in the reactor, and water is strongly sprayed through the nozzle. However, since the defoaming device, which is a foam defoaming device used in the past, uses treated sewage as the defoaming water, it is inevitable to install the defoaming tank and the pure water pump in the next step of the final settling, which results in additional burden on structure, machine construction, power, and maintenance. 10 shows a conventional sewage and wastewater treatment system that not only results in economic failure but also requires a deodorization facility.

In addition, the conventional defoaming method and apparatus by back-flowing a large amount of treated sewage back to the reaction tank for use as a parcel water, the hydraulic load is increased by the flow rate corresponding to the parcel water, the surface area loading rate of the sedimentation basin is increased There was a problem that the precipitation efficiency is lowered.

Odor is inevitable in the sludge concentration tank, digestion tank, and dehydrator, which constitute the sewage and wastewater treatment plant. In order to solve the odor problem, existing sewage treatment plants have installed odor removal facilities such as adsorption towers, alkaline washing towers, or soil deodorizers. Therefore, the initial facility cost is excessively invested, as well as an increase in operating costs due to replacement of activated carbon and chemicals, or a problem of preventing soil deodorization.

Therefore, the present invention has been made in order to solve the above problems only, intermittent aeration device that can reduce the facility cost and maintenance costs, and can efficiently apply the intermittent aeration method, which is a method for removing nitrogen and phosphorus in sewage, It is an object of the present invention to provide a defoaming and deodorizing device and methods thereof.

The present invention for realizing the above object is provided with one or more pumps in the reaction tank for wastewater treatment and is provided with an outlet pipe extending to the outlet of the pump, one or more ejectors are installed in the outlet pipe , The air supply pipe for supplying air is connected to the transfer site, the air supply pipe is connected to the air supply pipe, the air supply pipe or air supply pipe can be automatically opened and closed in conjunction with a timer or a redox potential. The air supply valve is installed, and the air supply pipe is connected to the odor air inlet pipe for introducing odor containing air exhausted from the odor source such as the concentration tank and the dehydrator chamber, and stirred by the pump and the air supply valve. In addition, intermittent abandonment is made and at the same time it can be removed odor It is a sewage processing apparatus to.

The air supply valve is an automatic valve such as a conventional (Solenoid) valve or a pneumatic valve, and opens and closes intermittently for a certain period of time to supply air to the reaction tank to be aerobic or to switch to anaerobic by blocking the air supply. The opening and closing of the air supply valve is performed by a timer or in conjunction with a DO controller or an ORP controller.

In another aspect, the present invention is one or more reaction tanks equipped with a water bubbler equipped with a rotary car for stirring the water flow, an air supply pipe connected to the water bubbler and blows air, an air supply pipe connected to the air supply pipe, the air supply pipe or It is installed in the air supply main, including an air supply valve that can be opened and closed automatically in conjunction with a timer or a redox potentiometer and a blower connected to the air supply main, characterized in that the aeration and stirring can be repeated alternately Sewage water treatment system.

Another waste water treatment method of the present invention comprises the steps of: agitating water in the reaction tank with a pump installed in the reaction tank for waste water treatment; Abandoning step of abandoning the odor-containing air exhausted from the odor generating source by the negative pressure by the outflow of the pulp to oxidize and decompose the odor source at the same time; Agitating the water flow with a rotary difference between the wastewater treatment method and the underwater aeration apparatus installed in the water of the reaction tank, the intermittent aeration being made by adjusting the suction of air in the aeration step; Aeration step of blowing air into the blower through an air supply pipe connected to the underwater aeration machine, dispersing air into fine bubbles with the rotary wheel, and stirring the water body; It is a wastewater treatment method that allows periodic aeration while stirring the water flow, including the step of stopping the air supply for a predetermined time by adjusting the supply of air in the aeration step.

Looking at the operation of the sewage treatment apparatus and treatment method of the present invention having such a structure will be as follows.

When the air supply valve installed at the air supply main connected to the ejector installed at the pump outlet is opened, air is sucked into the air supply pipe by the water flow discharged from the pump, and the air and water are mixed and ejected into the reaction tank. Oxygen dissolves in the reactor and becomes aerobic. In particular, when the air containing the odor exhausted from the concentration tank and the sludge dehydration chamber is supplied into the reaction tank through the air supply pipe, oxygen in the air is used for the breathing of the aerobic microorganisms, and the substances causing the odor are oxidized by the metabolic action of the aerobic microorganisms. Decomposition is removed to remove the odor, unlike the conventional sewage treatment plant, it is possible to perform a deodorization function without installing a separate deodorization facility.

When the air supply valve connected with the timer, the dissolved oxygen controller, the redox potential controller, etc. is closed, the air supply to the reactor is shut off and the anaerobic state is switched. At this time, since the pump is continuously operated, the stirring state that maintains the flow or suspension of the suspension is maintained by preventing the deposition of activated bio sludge in the fluidized bed and deposition of activated sludge by the flow of water ejected from the ejector.

By using the above-described intermittent aeration device and ice method as described above, it is possible to effectively treat nitrogen and phosphorus in sewage, improve aeration efficiency and sedimentation efficiency, suppress bubbles, as well as facility costs, power costs and maintenance costs. In terms of economics, it is possible to apply a biofilm contact material that can maintain a high concentration of nitrided microorganisms that are easily cleaned due to low yield coefficient.

1 is a perspective view of Embodiment 1 of a sewage and wastewater treatment apparatus according to the present invention.

2 is a perspective view of a second embodiment of the waste water treatment system according to the present invention.

3 is a schematic diagram of Embodiment 3 of a wastewater treatment system according to the present invention.

4 is a schematic view of Embodiment 4 of a wastewater treatment system according to the present invention.

5 is a schematic view of a fifth embodiment of a wastewater treatment system according to the present invention.

6 is a schematic view of a sixth embodiment of a sewage and wastewater treatment apparatus according to the present invention.

7 is a perspective view of a seventh embodiment of the sewage and wastewater treatment apparatus according to the present invention.

8 is a flow diagram of sewage and wastewater treatment using the sewage and wastewater treatment apparatus according to the present invention.

9 is a schematic diagram of a conventional intermittent aeration device.

10 is a system diagram of wastewater and wastewater treatment including a conventional defoaming apparatus.

* Explanation of symbols for main parts of the drawings

1,1a, 1f: Reactor 2: Pump

3: outlet 4: outlet

4a: branch pipe 4b: stirring control valve

5: ejector 6: air supply pipe

6a: water supply pipe 6b: supplementary water flow control valve

7: air supply main 8,81,82: air supply valve

8a: air control valve 9: water flow control pipe

10: water flow control valve 11: fluidized bed biofilm contact material

12: dividing wall 13: pump chamber

13a: pump chamber cover 14: defoaming water pipe

15: defoaming nozzle 16: defoaming water valve

17: underwater blower 18: blower

19: network 20: primary sedimentation basin

21: sedimentation basin 22: sludge injection tube

22a, 22b: sludge injection valve 23: odor air inlet pipe

24: sludge injection pump 25: conveying pump

25a: internal circulation means 25b: internal circulation tube

26: sludge fermentation tank 27: solid-liquid separation means

28: stirring apparatus 29, 30: aerobic reactor

31: rotary car 32: sludge conveying piping

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of a reaction tank implementing the first embodiment of the sewage and wastewater treatment method and apparatus equipped with a deodorizing function, defoaming function and intermittent aeration function according to the present invention, the aeration device of the present invention is pumped to the reaction tank (1) (2) is provided, the outlet port (3) of the pump (2) has an outlet pipe (4) is extended and the outlet pipe (4) ejector capable of injecting water or a mixture of water and air ( 5) are connected a lot. An air supply pipe 6 is connected to each ejector 5, and the air supply pipe is connected to an air supply main 7 having a large diameter, and an air control valve 8a and an air supply are supplied to the air supply line and the air supply main 7. The valve 8 is provided, respectively.

On the other hand, the outlet pipe (4) is connected to the water flow control pipe (9) having a water flow control valve 10 is to adjust the flow rate ejected from the ejector (5), this water flow control pipe (9) or The outflow pipe 4 is provided with the defoaming nozzle 15 only, and the defoaming water pipe 14 is connected, and the defoaming water pipe 14 is connected with the defoaming water valve 16 which can stop the injection of the defoaming water. . The pump 2 has a structure installed in a separate pump chamber 13 made of a separation wall 12.

In addition, in the present invention, by extending the pipe from the air supply valve (8) to form a malodorous air inlet pipe (23), by connecting the exhaust port through which the odor containing air generated in the concentration tank, sludge dehydrator, sludge fermentation tank, etc., odor containing The air can be introduced into the reactor 1 through the air inlet path described above.

Looking at the operation method of the sewage and wastewater treatment apparatus equipped with a deodorizing function and defoaming function and intermittent aeration function of the present invention configured as described above are as follows.

First, in the aeration stage in which the reactor 1 is operated in aerobic state to oxidize ammonia nitrogen contained in the sewage with nitrogen oxide, decompose organic matter (BOD), and ingest excess phosphorus, and operate the pump (2) while supplying air. Open the air supply valve (8) connected to (7). When water is ejected from the pump 2 through the ejector 5 at a high speed, the air supply valve 8, the air supply main body 7, and the air control are controlled by a negative pressure formed around the nozzle installed inside the ejector 5 While sequentially passing through the valve 8a and the air supply pipe 6, air is sucked into the ejector 5 and water flows in which fine air bubbles are mixed are ejected from the ejector 5 into the reactor 1. At this time, oxygen is dissolved in the water body inside the reaction tank 1 at the gas-liquid contact surface of the air bubble, thereby forming an aerobic state.

In this abandoned state, air bubbles mixed through the ejector 5 rise to the surface of the reaction tank 1 and a large amount of bubbles are generated. In the abandoned state in which the air supply valve 8 is opened, in order to suppress the generation of bubbles in the reaction tank 1, at the same time as the development of the air supply valve 5, the defoaming water valve 16 is also opened to open the pump 2 and discharge water flow. It is to be sprayed on the water surface of the reaction tank (1) through the air bubble nozzle (15). When the vesicles are sprayed, the foaming is suppressed as well as the vesicles in which the fine water flow comes into contact with the air reaches the reaction tank 1 in a state in which the dissolved oxygen is almost saturated, thereby bringing a synergistic effect of the aeration efficiency. When the reaction tank 1 is in this aerobic state, nitrification and decomposition of organic matter and phosphorus absorption by microorganisms are actively performed.

In addition, in the present invention, in order to realize the deodorizing method for removing the odor generated from the odor generating source such as the concentration tank, sludge dehydrator, the air supply main (7) to give up the reaction tank (1) by using the odor-containing air exhausted from the odor generating source (7). The malodorous air inflow pipe 23 is extended from the air supply valve 8 installed in the) to be connected to the exhaust port of the malodor generating source. When the air supply valve 8 installed in the air supply main body 7 connected to the ejector is opened, odor-containing air is sucked in and is ejected together with water into the reaction tank 1, and oxygen in the introduced air is an aerobic microorganism. It is used for breathing, and the odor causing substance is oxidized or degraded by metabolic action of aerobic microorganisms.

When the air supply valve is closed, even though the inflow of odorous air into some reactors is stopped, the sewage treatment plant is composed of a plurality of reactors and the aeration and aeration process is carried out so that the valve is opened and other odorous air is operated in aerobic state. As it continues to flow, the deodorizing function will continue. Since the substance causing odor may corrode metal depending on the type, when the odor-containing air is sucked into the inlet of the blower and sent to the reaction tank, the material rotates at a high speed and corrodes the rotor and the case of the blower being operated at a relatively high temperature. However, in the wastewater treatment apparatus according to the present invention, since there is no driving portion in the air passage path and is operated at a low temperature, corrosion problems do not occur.

During the intermittent aeration phase, the denitrification reaction and the non-aeration phase, ie, anaerobic phase, which release phosphorus, should be kept stirring so that suspension microorganisms will not be deposited even if the air supply is stopped. If the air supply is shut off by closing the air supply valve (8) connected to the air supply main (7) while the pump (2) continues to operate, the pump (2) continues to operate and water is continuously ejected through the ejector (5). Therefore, even though a negative pressure is formed in the air supply pipe 6, since the air supply valve 8 is closed, only water is ejected from the ejector 5 into the reaction tank 1 and air is not introduced. Therefore, the inside of the reaction tank 1 is maintained by the ejector 5 jetting water flow and the air supply is stopped, so that the oxygen is depleted by the respiration of the microorganism is converted to the anaerobic state. In this way, even in the anaerobic stage, the continuous stirring power is required so that the microorganisms or the microbial contact material 11 in the reaction tank 1 are not deposited, and the stirring is performed by the water stream ejected from the ejector 5.

In the anaerobic stage, free oxygen in the reaction tank (1) not only lowers the release of phosphorus from the microorganism but also favors free oxygen dissolved in water rather than oxygen bound with nitrogen oxides in respiration of microorganisms that contribute to denitrification. This prevents denitrification. Therefore, in the anaerobic stage, if the spraying of the parcel water in which a large amount of oxygen is dissolved continues, the nitrogen and phosphorus removal efficiency is lowered. However, in the anaerobic step, since no air is injected into the reaction tank 1, it is advantageous that the defoaming water valve 16 is also closed so that the amount of foaming in the reaction tank 1 is small, and thus, the defoaming water is not injected from the defoaming nozzle 15.

The air supply valve 8 is preferably composed of an automatic valve such as an electric valve or a pneumatic valve, and configured to be opened and closed in conjunction with a timer, a redox potential controller, or a dissolved oxygen controller to enable automatic operation. In the aerated state that the air supply valve 8 is opened, that is, a large amount of foam is generated in the aerobic step, the defoaming water valve 15 is also opened to spray the defoaming water from the defoaming nozzle 15 to suppress the generation of bubbles. In the non-aerated state in which the air supply valve 8 is closed, that is, in the anaerobic stage, not only the amount of foaming is small but also oxygen dissolved in the parcel water is mixed and the processing efficiency of nitrogen and phosphorus is lowered. Stop spraying. As described above, the opening and closing timing of the air supply valve 8 installed in the air supply main body 7 is similar to the opening and closing timing of the defoaming water valve 16 installed in the defoaming water pipe 14. Automatic operation is possible by putting it in operation.

In addition, the air supply valve 8a, which is an automatic valve, may be attached to each of the plurality of air supply pipes 6 connected to the plurality of ejectors 5 installed in the same reactor 1, but in case of mutual mismatch, anaerobic and aerobic characteristics As the transition of states is unclear, precise operation control is required if there is a need for installation. Therefore, it is advantageous to collect and connect the air supply pipes 6 to the large air supply main pipe 7 and to install the air supply valve 8 in the air supply pipe 7 to reduce the number of valves and reduce the possibility of malfunction. .

The water stream ejected from the ejector 5 serves to stir the activated sludge inside the reaction tank 1 or to flow the fluidized biofilm contact 11 in addition to forming a negative pressure for sucking air. However, depending on the operating conditions, if the water jet strength from the ejector 5 is too large, a strong shear force is formed inside the reaction tank 1, so that the biofilm on the surface of the contact material 11 sloughs or suspends growth. Sludge is dispersed and processing efficiency is lowered. Therefore, when the flow rate ejected from the ejector 5 is excessively open, the water flow control valve 10 partially opens a part of the flow rate discharged from the pump 2 to the surface of the reaction tank 1 or the pump chamber 13. It can be guided to the vicinity to adjust the flow rate ejected from the ejector (5).

That is, in order to reduce the flow rate ejected from the ejector 5, the flow rate control valve 10 is opened little by little to bypass the water near the surface of the reaction tank 1 so that the ejection flow rate can be controlled. When the mixing strength can be adjusted, and the biofilm is excessively attached to the biofilm contact material 11 to require artificial sloughing, the water flow control valve 10 is completely closed to close the water jet strength from the ejector 5. The structure can be increased.

In addition, the pump (2) may be of an underwater or ground type.

The air control valve 8a is a valve provided in each air supply pipe 7 to adjust the air intake amount supplied into the reaction tank 1. By adjusting the air control valve (8a) it is possible to adjust the amount of air sucked into each ejector (5) to be able to adjust the amount of air in the reaction tank (1). In particular, when the reactor 1 is in the form of a plug flow reactor, since the oxygen demand varies depending on the position of the reactor 1, the dissolved oxygen concentration is evenly distributed throughout the reactor 7 by adjusting the aeration amount of each ejector 5. It can be maintained.

In addition, in the case of using an underwater pump, it is advantageous that the pump 2 is installed in the reaction chamber 1 and installed in a separate pump chamber 13 composed of the separating wall 12. Complexes may be mixed into the reactor 1, and the compacts may close the small nozzles 15 having small diameters. Above all, it may be a problem that when the small fluidized bed biofilm contact material 11 is filled in the reaction tank 1, it may flow into the inlet of the pump 2, in particular, when the water pump 2 is used. The fluidized bed biofilm contact material 11 becomes an obstacle in the installation work after lifting the pump 2 for repair. That is, since the agitation is stopped when the pump 2 is lifted for repairing, the biofilm contact materials 11 are deposited on the bottom of the reaction tank 7, and the biofilm contact materials 11 stacked on the bottom when re-installation are removed. There is a problem in that the pump 2 becomes an obstacle preventing it from being seated in place. As a countermeasure against such a problem, the pump chamber 13 is formed by installing a porous separation wall 12 composed of a net or screen around the submersible pump 2, so that the water in the reaction tank 1 is well pumped. Inflow and contaminants are filtered out to prevent the closing of the vesicle nozzle 15, and above all, the fluidized bed microbial contact members 17 cannot enter the pump chamber 13, which is an obstacle to the work of installing the lifted pump 2 again. This will not be. In addition, it is preferable that the pump chamber cover 13a be provided so that impurities are not allowed to enter the pump chamber 13 from the outside.

In the non-aeration state in which the air supply is stopped, even if a negative pressure is applied to the ejector, the air supply valve is closed, so that only water is ejected, so that the stirring force tends to be weakened. In order to increase the output power of the ejector 5, the water supply supplement pipe 7a is provided so as to be immersed under the water surface of the reactor in the air supply main pipe 7. This is because the water in the reaction tank causes the water supply pipe 6a and the air supply main 7 to become negative when the air control valve 8a of the air supply main 7 is closed and the ejector 5 receives a negative pressure. Through the air supply pipe (6) is to be replenished with the ejector (5). This increases the water flow split power in the ejector 5. The water flow supplement pipe 6a can also be provided with a supplementary water flow control valve 6b which can be opened and closed if necessary.

2 is a schematic view of Embodiment 2 of a sewage and wastewater treatment system and treatment method according to the present invention.

The first embodiment is different from the first embodiment is provided with a branch pipe (4a) is connected to the ejector (5) in the outlet pipe (4), the agitator control valve (4b) is installed on the branch pipe (4a) ejector (5) By controlling the flow rate of the jet by), the stirring strength can be adjusted. This makes it possible to adjust the flow of water supplied from the pump to some of the ejectors 5 when it is necessary to partially agitate or to lower the stirring force. That is, the outlet pipe 4 of the pump 2 is installed to extend the outlet pipe 4, and each of the pipe lines from the outlet pipe 4 to the ejector 5 can be extended and the flow rate can be adjusted in each pipe line. By installing a spit it is possible to directly control the flow rate ejected from each ejector (5).

3 is a schematic view of Embodiment 7 relating to a wastewater treatment system and treatment method according to the present invention.

Reactors 1a and 1f are provided with a hydrofoil device 17 provided with a rotary car 31 which can stir water or disperse air compressed from the outside into fine air bubbles and mix and stir the water together. have. The air supply pipes 6 are collected (in the case of a plurality of reaction tanks) and connected to an air supply main 7 and to a blower 18 for pumping air to the other side of the air supply main 7. The air supply pipe 7 is provided with air supply valves (81, 82) that can be automatically opened and closed in conjunction with a timer or a redox potential, and the operating method of the device is as follows.

In order to keep the reaction tanks 1a and 1f in the abandoned state as well as in the non-aerated state, the inside of the reaction tanks 1a and 1f must be kept in agitated state so that the suspension microorganisms or the singular membrane contact material 11 are not deposited. In this case, an intermittent aeration method may be used, in which a blower is provided in each case and the operation of the blower is started or stopped whenever a replacement of the abandoned state and the non-aeration state is required in the reactor. However, in this case, the facility capacity of the blower is increased, idle facilities are generated, and the instantaneous power load increases, resulting in an uneconomical effect.

In contrast, in the present invention, the air supply valves 81 and 82 are always operated in a state in which the rotor 31 and the blower 18 provided in the underwater bubble device 17 are always operated regardless of the aeration / non-aeration state. The reactor that is opened is abandoned and operated in aerobic state, and the reactor that is closed is operated in aerobic agitation state and converted to anaerobic state.

Referring to the operation method according to the present embodiment in more detail, the air blower 17 and the underwater air blower 17 is open in any one of the air supply valve 82 and the other air supply valve 82 ), The reaction tank 1a in which the air supply valve 81 is opened is operated in the abandoned state, and the reaction tank 1f in which the air supply valve 82 is closed is operated in the aeration state. In addition, when the open / closed state of the supply valves 81 and 82 is replaced, the reaction tank 1a that was operated in the abandoned state in the previous step is operated by changing to the abandoned state because the reaction tank 1f that has been operated in the non-aerated state is operated. The reactors 1a and 1f are operated by the intermittent aeration method in which the aeration / non-aeration state is replaced.

When the wastewater treatment system is configured and operated according to the present embodiment, the operation rate can be increased with a relatively small blower 18 facility capacity. For example, in the case of sewage treatment which requires abandonment for 1 hour and aerobic operation for 1 hour, a 2 series reactor is constructed, but a blower having a capacity required in the 1 series reactor is installed and operated continuously. The operation of the blower 18 is operated by repeating the opening and closing operation at an interval of 1 hour by interlocking the air supply valve with a timer so as to supply air to the reactors of each series alternately. Blower capacity can be reduced by half.

As another example, in the case of sewage treatment that requires abandonment for 2 hours and aerobic operation for 1 hour, a three-stage reactor is constructed, but the blower with the capacity required in the two-stage reactor is installed and operated continuously. The air supply valves of each series of reactors are operated to close for 1 hour after opening for 2 hours, but the operation time of the blower itself is increased by the operation of the blower itself by interlocking with the timer so as to sequentially match the opening and closing times. It can be reduced to 2/3. Even if the blower is prevented from overheating and a spare facility is installed in preparation for a failure, the intermittent aeration method according to the present invention also reduces the capacity of the spare facility.

When the fluidized bed biofilm contact member 11 is filled in the reaction tanks 1a and 1f, the biofilm contact member 11 flows into the opening under the underwater bubbler 17 and collides with the rotor wheel 31 to be damaged. Or may damage the rotary car 31, it is preferable to form a mesh 19 composed of a grid, a screen, a porous plate, etc., in accordance with the size of the biofilm contact member 17 under the underwater aeration device 17. Do.

4 is a schematic view of Embodiment 4 of the sewage and wastewater treatment system and treatment method according to the present invention. .

In this embodiment, the reaction tanks 1a and 1f are connected in series to two or more sets, and among the reaction tanks 1a and 1f, the first step of the first reaction tank 1a is provided with a primary needle battery 20 and the final reaction tank. (1f) Next, the sedimentation basin 21 is connected, and the influent sewage is treated while sequentially passing through the primary sedimentation cell 20, the reaction tanks 1a and 1f and the sedimentation basin 21. In the primary sedimentation cell 20 into which sewage is first introduced, fresh sludge mainly composed of organic solids is precipitated and the supernatant is introduced into the first reactor 1a, and the reactors 1a and 1f and the sedimentation basin 21 are configured in series. After sequentially processing through the activated sludge mainly composed of microorganisms is to be separated from the sedimentation basin 21, the sewage water to flow out.

In addition, the activated sludge precipitated in the sedimentation basin 21 can be taken out and introduced into the initial reactor 1a so that the suspension microorganism concentration can be maintained in the reaction tanks 1a and 1f, and the sludge conveying pump 25 and Activated sludge is conveyed using a sludge conveying facility such as a sludge conveying pipe 32. The sludge transport facility may be omitted when the biofilm contact material 11 is filled in the reaction tanks 1a and 1f to mainly attach and grow microorganisms.

In the present embodiment, the reaction tanks 1a and 1f are operated by the intermittent aeration method. That is, when operating in an aerobic state, it is advantageous that the organic load is small so that free oxygen can be used by the nitrifying microorganism, which is an independent nutrient microorganism. Do. Therefore, the concentration of organic matter in the sewage flowing into the reactors 1a and 1f should be lowered by removing the organic matter as much as possible from the primary needle battery 20. However, in the aerobic state, organic matter should be abundantly present in the reaction tanks (1a and 1f) to quickly consume dissolved free oxygen due to the metabolic activity of aerobic microorganisms and to use combined oxygen combined in the form of nitrogen oxides. Progressive anoxic state is formed and furthermore, bound oxygen is depleted and can be converted into anaerobic state in which phosphorus is effectively released from activated sludge. Therefore, in this embodiment, the sludge injection pump 24 and the sludge injection pipe 22 as a method of extracting the raw sludge precipitated in the primary settling cell 20 and injecting all or part of the reaction tanks 1a and 1f. Use The raw sludge extracted from the initial settler 20 is injected when the reactors 1a and 1f are in the aerobic state, and used as an electron donor for the reduction reaction of nitrogen oxide, while the rapid conversion from the anaerobic state to the anaerobic state is performed. In order to be used as an electron donor to deplete free oxygen.

The sludge injection valves 22a and 22b provided in the sludge injection pipe 22 are configured as automatic valves so that the reaction tank is opened and closed by interlocking with an air supply valve supplying air to the reaction tank when the aeration valve is abandoned. It is desirable to avoid sludge injection when there is. Accordingly, fresh sludge can be injected only when the reaction tanks 1a and 1f are in the non-aerated state. In addition, the operation of the sludge injection pump 24 may be operated in conjunction with the air supply valves 8, 81, 82 to automate the injection of fresh sludge. Since the raw sludge may include fine contaminants that could not be removed in the pretreatment facility, it is advantageous to inject the raw sludge from which the contaminants have been removed through a screen formed of a net or a porous plate into the reactors 1a and 1f.

In the present invention, in addition to the nitrogen removal by the intermittent aeration method, a pump that can circulate by flowing back water to the part or all of the prestage reaction tank (1a) to perform the denitrification method in parallel An internal circulation means 25a and an internal circulation tube 25b are provided.

The initial reaction tank in which the sewage flows from the biological sewage treatment plant has high organic matter concentration, low nitrogen oxide concentration, and as the stage of the reaction tank is repeated, the concentration of organic matter becomes lower and the concentration of nitrogen oxide increases.

Therefore, the water body of the post-stage reactor with high nitrogen oxide concentration is internally circulated to the pre-stage reactor with high organic concentration, so that organic matter contained in the influent sewage can be used as an electron donor for denitrification. This nitrogen removal method is called total denitrification method and many variations such as Bardenpho method and A / O method have been used until now.

In the nitrogen removal method by the intermittent aeration method, if the organic matter is not sufficiently supplied in the aeration state or the residence time is insufficient, the experiment shows that there is a tendency of nitrogen oxide that the denitrification reaction has not yet occurred in the reaction tank installed in the rear stage. there was. Therefore, if the sewage from the back stage reactor containing nitrogen oxides is introduced into the sewage system and internally circulated to the first reactor or the previous stage with a relatively high concentration of organic matter, the nitrogen removal by the total denitrification method is carried out when the preceding stage is operated under aerobic agitation. Can be parallel to improve the nitrogen removal efficiency.

In consideration of the possible balance of organic matter and nitrogen oxides in the sewage treatment plant, the initial reaction tank can always be operated under aeration without agitation, which is also included in the scope of the present invention. Such a total denitrification method can also be used in Example 5 or Example 6 described later.

5 is a schematic view of Embodiment 5 of a sewage and wastewater treatment apparatus and treatment method according to the present invention.

The reactors 1a and 1f are connected in series with two or more tanks, and the first settling basin 20 is provided to pass the settling process in front of the first reactor 1a, and the settling basin 21 is connected behind the final reactor 1f. An aerobic reaction tank 29 is installed between the first reactor 1a and the primary needle battery 20 so that the symbolic number of the primary needle battery 20 passes through the aerobic reaction tank 29. It relates to an embodiment configured to be introduced into the reaction tank (1a), or further comprises an aerobic reaction tank 30 in the middle of the initial reaction tank (1f) and the settling basin (21).

The sewage introduced for the first time has a low nitrogen oxide concentration, and the effluent of the final reaction tank 1f, which is operated in an aeration state, may have nitrogen gas attached to the microbial floc, thereby reducing sedimentation. Therefore, in the present embodiment, the first inflow water is first introduced into the aerobic reaction tank 29 which operates in an aerobic state at all times to increase the nitrogen oxidation rate or the effluent water of the final reaction tank 1f operated by the intermittent aeration method to the aerobic reaction tank 30. The aerobic reaction tank (29, which is always operated in the aeration state at the front or rear stages of the reaction tanks 1a and 1f operated in an intermittent aeration method in order to improve the sedimentation at the final stage and air-stripping nitrogen gas in the final stage 30).

In the example of FIG. 3 shown above, the raw sludge precipitated in the primary sedimentation cell 20 was injected into the aerobic reaction tanks 1a and 1f and used as an electron donor.

However, since the raw sludge is a mixture of solid organic substances having a large molecular weight, it is not easily used or decomposed by microorganisms, so the denitrification reaction rate is slow and when the undecomposed solids elute the organic matter from the settling basin 21, the dissolved organic matter is dissolved. It may leak and the processing efficiency may fall. In order to solve this problem, in the present embodiment, a sludge fermentation tank 26 is provided to anaerobic fermentation of fresh sludge extracted from the primary sedimentation cell 20 to convert the solid organic matter into a soluble organic substance having a low molecular weight, and the fermented liquid organic substance. Was introduced to the apparatus and method for injecting the reaction tanks (1a, 1f) while operating in a non-aerated state.

The rapid denitrification requires abundant supply of organics that are readily available to microorganisms, with acetate having the simple molecular structure being the most advantageous, followed by butyl salts and alcohols. The raw sludge can be easily fermented into organic acids by fermentation microorganisms, and fermented sludge has the highest acetate, followed by butyl salt, propyl salt and alcohols. Since the organic acid fermentation is terminated at the previous stage of the difficult methane fermentation, the operation management is easy and the capacity of the sludge fermentation tank 26 is not largely required.

The raw sludge contains minerals such as fine earth and sand which cannot be decomposed by microorganisms, or the sludge fermentation tank 26 may contain solid organic matter that has not been fermented. The outlet of the sludge fermentation tank 26 may be subjected to a solid-liquid separation means 27 such as a sedimentation basin or a centrifuge to remove solids contained in the effluent of the sludge fermentation tank 27.

In addition, two or more sets of sludge fermentation tanks 26 are installed as a solid-liquid separation means of the sludge fermentation broth so that the sludge flows in series, and one of the two sets of sludge fermentation tanks is one of the sludge fermentation sludges, and the other one is the fermentation sludge. It may be configured to alternately use as a solid-liquid separation means for precipitating to separate the unliquefied solids or fine soils contained in the fermentation sludge and then inject only liquid organic matter when the reaction tanks (1a, 1f) are aerated. have. For effective sludge fermentation, the sludge fermentation tank 26 is preferably subjected to the stirring process by the stirring device 28, and alkali may be injected for pH adjustment.

6 is a schematic view of Embodiment 7 relating to a wastewater and wastewater treatment apparatus and a treatment method according to the present invention.

In the present embodiment, two or more tanks are connected in series, and after the final reactor 1f, a sedimentation basin 21 is connected, and the influent sewage sequentially connects the reaction tanks 1a and 1f and the sedimentation basin 21. It will be processed while going through.

In the present embodiment, the wastewater and wastewater treatment apparatus and treatment method which are configured by omitting the primary settling battery 20, the sludge fermentation tank 26, and the like in the third embodiment or the fourth embodiment. The third or embodiment 4 shown above has advantages in terms of treatment efficiency and economics in large sewage treatment plants. However, in the case of small and medium-sized sewage treatment plants, the number of thin structures for installing the primary sedimentation battery 20 or the sludge fermentation tank 26, etc. increases, and the configuration of the apparatus becomes complicated. Therefore, as in the present embodiment, the installation of the primary precipitating battery 20 may be omitted, and the apparatus may be simply configured so that the organic material may be used as an electron donor that is deficient in denitrification in an aerobic state. Increasing the total amount of (1a, 1f) is rather economical and facilitates driving management.

The reactors 1a and 1f are operated in an intermittent aeration method in which aeration and aeration are alternately repeated, and an aerobic reactor is operated in front of the first reactor 1a or after the final reactor 1f at all times aerobic. It can be installed as, it is also included in the scope of the present invention.

In aerobic agitation, where anoxic or anaerobic conditions are required, the dissolved oxygen in the atmosphere adversely affects the denitrification and phosphorus release reactions. When the surface of the reaction tanks 1a and 1f is exposed to the atmosphere even in the aeration state, oxygen in the atmosphere is dissolved into the reaction tanks 1a and 1f. However, when the water surface of the reactor is sealed, a problem arises that the abandoned air is not smoothly exhausted when operating in the abandoned state. Therefore, if a small specific gravity of synthetic resin balls and pieces of foamed styropol are hollowed so as to be stacked on the surface of the reactors 1a and 1f, the aeration air can be smoothly exhausted, and in the aerobic agitation state. It is possible to block the air from being dissolved in the water body in the reaction tank (1a, 1f). The method of sealing the reaction tanks (1a, 1f) and installing an air vent valve is also included in the scope of the present invention.

7 is a perspective view of a reaction tank implementing a wastewater treatment method and apparatus further equipped with an internal circulation function in Example 1 having a deodorizing function, an antifoam function, and an intermittent aeration function according to the present invention. The aeration device of the present invention is composed of two or more tanks in series, one or more pumps 2 are provided in the final tank, the intermediate tank or the rear stage reactor 1f, and the outlet port 3 of the pump 2 The outflow pipe 4 extending from) is installed. At least one ejector 5 is installed in the first stage reaction tank 1a of the reaction tank 1f in which the pump 2 is installed, but the pump installation is omitted, and the outlet pipe 4 of the pump 2 installed in the rear stage reaction tank 1f is installed. ) And the ejector 5 of the previous stage reaction tank 1a are connected and installed. The air supply and defoaming apparatus and the like have the same structure as in the first embodiment.

Looking at the operation method of the sewage, wastewater treatment apparatus further provided with an internal circulation function of the present invention configured as described above are as follows.

When the pump 2 is operated, the post-stage reactor 1f in which the pump is installed is subjected to aeration or aeration, and at the same time, the discharged water of the pump is circulated back to the reactor 1a of the previous stage, so that Since it is ejected from the installed ejector (5), the aforesaid reaction tank (1a) in the aforesaid reaction tank (1f) by the pump (2) installed in the aeration or aeration aeration is made, as well as a later step without having a separate internal circulation means Water in the reaction tank 1f is internally circulated to the previous stage reaction tank 1a.

According to this embodiment, sewage flows into the water body of the post-stage reaction tank 1f containing nitrogen oxides without introducing a separate internal circulation means 25a and the internal circulation tube 25b as in Example 5, and thus relatively organic matter. It is possible to circulate internally to a high concentration of the first stage reaction tank (1a). Accordingly, when the first stage reaction tank (1a) is operated under aerobic agitation, nitrogen removal by the total denitrification method can be performed in parallel to improve the nitrogen removal efficiency. It becomes possible.

In order to realize the original purpose of the intermittent aeration, the air supply valve 7 and the air supply valve are also used in this embodiment in which the pump 2 installed in the rear stage reactor 1f is used together as the aeration and agitation means of the front stage reactor 1a. 8) The air supply means for realizing the intermittent aeration method and the defoaming water valve 16 related to the oxygen dissolution should be configured to be operated independently for each of the reaction tanks 1a and 1f.

In this embodiment, since the pump installation is omitted in the previous stage reaction tank, it is economical in terms of facility cost, and the intermittent aeration method, the defoaming method, and the deodorization method are the same as in the first embodiment.

8 is a sewage treatment system diagram using a sewage and wastewater treatment method and apparatus equipped with a defoaming function, a deodorizing function and an intermittent aeration function according to the present invention.

In the present embodiment, the wastewater treatment apparatus and method of Example 1 eliminates the defoaming tank, the defoaming pump, the deodorizing facility, and the blower, and thus, unlike the conventional treatment system of FIG. It is not necessary to know that a separate blower and defoaming pump are omitted. In particular, when using the seventh embodiment, since the intermittent aeration device is equipped with an internal circulation means without installing a separate internal circulation means, it is possible to perform a total denitrification method by internal circulation, which is excellent in nitrogen removal efficiency and economical The device can be realized. In addition, it is very economical in terms of machinery and plumbing facilities because the pipes for transporting air and parcel water from the blower and the defoaming tank to the biological reaction tank become unnecessary.

As described above, by using the sewage treatment apparatus and method according to the present invention, the aeration efficiency and sedimentation efficiency are improved, foaming is suppressed in the reaction tank, and the biofilm method for filling the contact material is facilitated. In addition, it is possible to omit or reduce the capacity of the separate blower and the corresponding blower chamber building, and it is unnecessary to install a defoaming tank, a defoaming water pump and a deodorizing facility that suppresses the foaming of the aeration tank, and internal circulation is possible, thereby allowing the construction work. In addition, the cost of plumbing, construction, power, and maintenance can be reduced. In particular, the efficiency of removing nitrogen and phosphorus, which are the causes of eutrophication, can be effectively increased. '

Claims (40)

One or more pumps 2 are provided in the reactor 1, and an outlet pipe 4 extending from the pipe 2 to the outlet port 3 of the pump 2 is provided, and the outlet pipe 4 has an ejector 5. ) Is installed at least one and the air supply pipe (6) for supplying air is connected to the ejector (5), the air supply pipe (6) is connected to the air supply main (7), the air supply main ( 7) is provided with an air supply valve (8) that can be automatically opened and closed in conjunction with a timer or a redox potential, etc., and the air supply main (7) is odor exhausted from the source of odor such as a concentration tank or dehydrator chamber The odor air inflow pipe 23 is connected to the inlet air, so that the pump 2 and the air supply valve 8 are agitated and intermittent aeration is made, and at the same time the odor can be removed. Sewage water treatment device characterized in that. The wastewater treatment apparatus according to claim 1, wherein a water supply supplement pipe (6a) is connected to the air supply main pipe (7a) so as to be submerged under the water surface of the reactor. The wastewater treatment according to claim 1, characterized in that the outlet pipe (4) is provided with a branch pipe (4a) to which the ejector (5) is connected, and the branch pipe (4a) is provided with a stirring control valve (4b). Device. 2. The outlet pipe (4) according to claim 1, wherein the outlet pipe (4) has a water flow control pipe (9) having a water flow control valve (10) or a small water nozzle (15) and a small water pipe (14) having a small water valve (16). Wastewater treatment apparatus, characterized in that the branched connection. The sewage water treatment apparatus according to claim 1, wherein the surface of the reactor 1 is suspended by suspending a small object such as a synthetic resin ball or a foamed styropol, which is empty, so that the surface of the reactor and the air in the air are blocked. . The second stage reactor 1f, which is composed of two or more tanks in series and installed in the final or intermediate stage, includes one or more pumps 2 and an outlet pipe extending from the outlet port 3 of the pump 2 to the tube. (4) is provided, at least one ejector (5) is installed in the reaction tank (1f) and the previous stage of the reaction tank (1a) provided with the pump (2), and the outlet pipe (4) and the ejector (5) Is connected and installed, the ejector 5 is connected to the air supply pipe 6 for supplying air, the air supply pipe 6 is connected to the air supply main (7), the air supply main ( 7) is provided with an air supply valve (8) that can be automatically opened and closed in conjunction with a timer or a redox potential, etc., and the air supply main (7) is odor exhausted from the odor generating source such as a concentration tank or dehydrator chamber Odor air oil that can introduce contained air Pipe 23 is connected becomes the stirring and the internal circulation and intermittent aeration performed by the pump 2 and the air supply valve 8 at the same time, wastewater treatment device, characterized in that the odor is able to be removed. 7. The wastewater treatment apparatus according to claim 6, wherein a water supply supplement pipe (6a) is connected to the air supply main pipe (7a) so as to be submerged under the surface of the reactor. The wastewater treatment according to claim 6, wherein the outlet pipe (4) is provided with a branch pipe (4a) to which the ejector (5) is connected, and the branch pipe (4a) is provided with a stirring control valve (4b). Device. 7. The outlet pipe (4) according to claim 6, wherein the outlet pipe (4) includes a water flow control pipe (9) having a water flow control valve (10), or a defoaming water pipe (14) having a defoaming nozzle (15) and a defoaming water valve (16). Wastewater treatment apparatus, characterized in that the branched connection. According to claim 6, wherein the air supply pipe (7) is divided into units installed in the reaction vessel unit, the ejector (5) and the air supply main pipe 7 installed in the reaction tank is characterized in that connected to the air supply pipe (6) Sewage water treatment device. The wastewater treatment apparatus according to claim 6, wherein the surface of the reactor is suspended by suspending a small object such as a synthetic resin ball or a foamed styropol, which is empty, to block the surface of the reactor and air in the atmosphere. At least one reactor 1 having an underwater aeration apparatus 17 having a rotor 31 for agitating the water, an air supply pipe 6 connected to the underwater aeration apparatus, for blowing air, and the air supply pipe ( 6) an air supply valve (7) connected to the air supply pipe (7) connected to the air supply pipe (6) or the air supply pipe (7), which can be automatically opened and closed in conjunction with a timer or a redox potential (81). And a blower connected to the air supply pipe (7) to allow aeration and agitation to be repeated alternately. The method of claim 12, wherein the reaction tank 1 is filled with a biofilm contact material 11 and the opening 17 of the underwater device 17 is provided with a mesh 17 composed of a lattice, a screen, a porous plate and the like. Sewage water treatment device. The wastewater treatment apparatus according to claim 12, wherein the surface of the reaction tank 1 is suspended by suspending a small object such as a synthetic resin ball or a foamed styropol, which is empty, so that the water surface of the reaction tank and air in the atmosphere are blocked. . One or more sewage treatment tanks (1) for treating wastewater and intermittent aeration devices (1) and a front and rear of the reaction tank (1), which are provided with an aeration device and an agitator, respectively, are installed and introduced therein. The sewage is treated to pass through the primary settling cell 20, the reaction tank 1, and the settling basin 21 in sequence, and the raw sludge contained in the influent sewage is separated after being precipitated in the primary settling cell 20. Water flows into the reaction tank 1, and activated sludge contained in the effluent water of the reaction tank 1 is allowed to flow out of the supernatant after sedimentation and separation in the settling basin 21, and precipitated in the primary settling cell 20. Sludge injection pump (24) and sludge injection pipe (22), which is capable of extracting fresh sludge and injecting all or part of the reaction tank (1), is installed. The wastewater treatment apparatus according to claim 15, wherein an aerobic reaction tank (27) is provided in front of the initial reaction tank in the reaction tank (1). The wastewater treatment apparatus according to claim 15, wherein an aerobic reaction tank (30) is installed between the final reaction tank (1) and the settling basin (21). The wastewater treatment apparatus according to claim 15, wherein the rear stage reaction tank or the final reaction tank of the reaction tank (1) is provided with internal circulation means (27a) for internal circulation to the previous stage reaction tank or the initial reaction tank of the reaction tank (1). . 16. The wastewater treatment apparatus according to claim 15, wherein the surface of the reactor 1 is suspended by suspending a small object such as a synthetic resin ball or a foamed styropol, which is empty, to block the surface of the reactor and air in the atmosphere. . According to claim 15, The primary sedimentation basin (20) is provided with a fermentation tank 26 for fermenting the raw sludge, sludge injection pump for taking out the sludge fermented in the fermentation tank and injecting into the reaction tank (1) 24) and the wastewater treatment apparatus, characterized in that the sludge injection pipe 22 is installed. 18. The wastewater treatment apparatus according to claim 17, wherein the aerobic reaction tank (30) is provided with an internal circulation means (25a) to internally circulate to the previous stage or the first reaction tank of the reaction tank (1). The sludge fermentation tank (26) is provided with a solid-liquid separation means (27) such as a sedimentation basin or a centrifuge or the sludge fermentation tank (27) is composed of two tanks in series to provide a sludge fermentation and fermentation sludge load. Wastewater treatment apparatus, characterized in that it can be used sequentially or alternately. Two or more tanks for sewage treatment are installed in series, where the aeration device and agitator are installed to allow intermittent aeration. The sedimentation basin 21 is connected after the final reactor 1f. After passing through the reaction tank sequentially, the next stage reaction tank or the final reaction tank 15 is provided with an internal circulation means 27a and internally circulated to the previous stage reaction tank or the first reaction tank 1a, and to the effluent of the final reaction tank 1f. The activated sludge contained sewage water after the sedimentation in the sedimentation basin (21) characterized in that the sewage water is discharged. The wastewater treatment apparatus according to claim 23, wherein an aerobic reaction tank (29) is provided in front of the initial reaction tank (1a) of the reaction tank. The wastewater treatment apparatus according to claim 23, wherein an aerobic reaction tank (30) is provided between the final reaction tank (1f) and the settling basin (21) in the reaction tank. 24. The wastewater treatment apparatus according to claim 23, wherein a primary settling battery is installed in front of the first settling tank (1a) in the reaction tank, and a withdrawal pump is installed in the primary settling battery to extract and remove the fresh sludge. The wastewater treatment apparatus according to claim 23, wherein the surface of the reactor is suspended by suspending a small object such as a synthetic resin ball or a foamed styrofole to empty the surface of the reactor. The wastewater treatment apparatus according to claim 25, wherein the aerobic reaction tank (30) is provided with an internal circulation means (25a) to internally circulate to the previous stage or the initial reaction tank (1a) of the reaction tank. Stirring the water in the reaction tank with a pump installed in the reaction tank for sewage treatment; The aeration step of oxidizing and decomposing odor-causing substances at the same time by inhaling the odor-containing air exhausted from the odor generating source by the negative pressure caused by the effluent of the pump, and controlling the intake of air in the aeration step to achieve intermittent aeration. Wastewater treatment method comprising the step of. Agitating the water flow with the rotary car of the underwater aeration apparatus installed in the water of the reactor, aeration by blowing air to the blower through the air supply pipe connected to the underwater aeration equipment, while aeration of the air by the rotary difference to disperse the fine bubbles and stirring the water body Aeration step to make; Adjusting the supply of air in the aeration step, including the step of stopping the air supply for a predetermined time, the wastewater treatment method to enable intermittent aeration while stirring the water flow. Precipitation step of precipitation of influent sludge, Intermittent aeration step of repeating aeration and non-aeration agitation in a reaction tank consisting of two or more tanks, and precipitation for use as an electron donor for reduction of nitrogen oxides Extracting fresh sludge and injecting the intermittent aeration reactor when it is in a non-aeration state; Activated sludge precipitation step of precipitating activated sludge contained in the effluent from the reaction tank; Sewage water treatment method comprising an outflow step of outflowing the supernatant after the activated sludge precipitation step. 32. The method for treating sewage water according to claim 31, wherein in the reaction tank consisting of two or more tanks, the water of the after-stage reaction tank or the final reaction tank is internally circulated to the previous-stage reaction tank or the first reaction tank, and the denitrification method and the intermittent aeration method are performed in parallel. 32. The wastewater treatment method according to claim 31, wherein an aerobic treatment step is added in front of the reaction tank so that a reaction tank is always operated in an aerobic state as the first reaction tank. 32. The wastewater treatment method according to claim 31, further comprising an aerobic treatment step in which a reaction tank is always operated in an aerobic state as a final reaction tank after the reaction tank. 32. The method of claim 31, wherein the step of extracting the fresh sludge and injecting it into the intermittent aeration reaction tank is performed by extracting the precipitated fresh sludge and performing anaerobic fermentation and then injecting it into a part or all of the intermittent aeration reaction tank while the reactor is in a non-aeration state. By using the fermentation sludge as an electron donor required for the reduction reaction of nitrogen oxides. 32. The method of claim 31, wherein the step of injecting the fresh sludge into the intermittent aeration reaction tank is linked to the supply of air for aeration to inject the sludge into the reactor to stop the air supply. 35. The wastewater treatment method according to claim 34, wherein the denitrification method and the intermittent aeration method are performed in parallel by internally circulating from the reaction tank always operated in an aerobic state as the final reaction tank to the previous stage reaction tank or the initial reaction tank. 36. The wastewater treatment method according to claim 35, wherein the sludge is fermented and the solids are separated by a solid-liquid separation means such as a sedimentation basin or a centrifugal separator to inject a liquid fermentation sludge when the reactor is in an aeration state. 36. The method of claim 35, wherein the step of injecting the fermentation sludge into the intermittent aeration reaction tank is linked to the supply of air for aeration to inject the sludge into the reactor to stop the air supply. 38. The wastewater treatment method according to claim 32 or 37, wherein the initial reaction tank into which the sewage is introduced is always kept in an aeration agitation.