JP4932410B2 - Nitrogen-containing wastewater treatment apparatus and nitrogen-containing wastewater treatment method - Google Patents

Description

  The present invention relates to a nitrogen-containing wastewater treatment apparatus and a nitrogen-containing wastewater treatment method for treating nitrogen-containing wastewater with microorganisms in sludge.

  Conventionally, as a wastewater treatment apparatus for treating nitrogen-containing wastewater, as disclosed in Japanese Patent Laid-Open No. 2006-136853 (Patent Document 1), denitrification treatment by denitrifying bacteria in a denitrification tank and nitrifying bacteria in a nitrification tank There is a wastewater treatment equipment facility that performs nitrification treatment with This waste water treatment facility includes a pre-aeration tank, a denitrification tank, and a nitrification tank.

  The above aeration tank is an aerobic activated sludge tank. By aeration of waste water and activated sludge under aerobic conditions, substances that become the basis of inhibitors and malodorous substances in the subsequent nitrification treatment are transpired or changed to different substances. The effect is removed in advance. The denitrification tank is an anaerobic sludge tank, which mainly decomposes nitrogen-containing components such as nitrite nitrogen and nitrate nitrogen into nitrogen gas in the presence of a hydrogen donor under anaerobic conditions. The nitrification tank is an aerobic activated sludge tank, which mainly decomposes organic nitrogen into ammonia nitrogen under aerobic conditions, and further converts it into nitrite nitrogen, nitrate nitrogen, and the like. A part of the treated waste water is circulated back to the denitrification tank with a circulation pump.

However, in the wastewater treatment facility disclosed in Patent Document 1, the denitrifying bacteria are simply introduced into the denitrifying tank, and the nitrifying bacteria are merely introduced into the nitrifying tank. Therefore, the microorganisms that are the denitrifying bacteria and the nitrifying bacteria are stabilized and not sufficiently activated, and the treatment ability by the microorganisms is not sufficiently extracted. Therefore, there is a problem that the nitrogen removal rate is less than about 90%, and only low processing efficiency can be obtained.
JP 2006-136853 A

  Accordingly, an object of the present invention is to provide a nitrogen-containing wastewater treatment apparatus and a nitrogen-containing wastewater treatment method capable of stabilizing and activating microorganisms and improving the treatment capacity of the microorganisms.

In order to solve the above problems, the nitrogen-containing wastewater treatment apparatus of the present invention is
A micro / nano bubble generator having a micro / nano bubble generator and generating micro / nano bubbles in the introduced water;
A micro / nano bubble adhering tank for adhering micro / nano bubbles in water containing micro / nano bubbles introduced from the micro / nano bubble generating tank to microorganisms in the introduced microorganism sludge;
It has a water depth of 7 m or more and is filled with a filler for adhering micro-nano bubbles, and microbial sludge from the micro-nano bubble adhering tank and nitrogen-containing waste water from the outside are introduced into the introduced nitrogen-containing waste water. A nitrification tank for nitrification treatment,
While being installed in the nitrification tank and having an inlet for introducing the microbial sludge and the nitrogen-containing wastewater at the upper end, the microorganism sludge and the nitrogen-containing wastewater introduced from the inlet at the bottom A nitrification tank lower introduction pipe having a discharge hole for discharging to the lowermost part of the nitrification tank ;
It has a water depth of 7 m or more, is filled with a filler for attaching micro-nano bubbles, water to be treated that has been subjected to nitrification by the nitrification tank is introduced, a hydrogen donor is added, and the introduced coverage is introduced. A denitrification tank that denitrifies the treated water;
The denitrification tank is installed in the denitrification tank and has an inlet at the upper end through which the water to be treated from the nitrification tank is introduced. A denitrification tank lower introduction pipe having a discharge hole for discharging at the bottom;
A re-aeration tank that has an aeration apparatus and that microbially decomposes the hydrogen donor in the water to be treated that has been introduced in the denitrification tank and into which the water to be treated has been excessively added in the denitrification tank. It is characterized by having.

  Here, the micro / nano bubble is a micro bubble which is a bubble having a diameter of 1 μm to several tens of μm at the time of generation and a nano bubble which is a bubble having a diameter of several hundred nm or less at the time of generation. Air bubbles having a diameter of nm to 10 μm. Note that the microbubbles are changed into micro-nanobubbles by contraction movement after generation.

  As a characteristic of micro-nano bubbles, it may adhere to an object. If the micro / nano bubbles adhere to the microorganisms in the sludge, the microorganisms can easily use (consume) the micro / nano bubbles, and the microorganisms can be activated easily.

  According to the said structure, a micro nano bubble generation tank generates micro nano bubble in the introduce | transduced water, and produces | generates micro nano bubble containing water with much micro nano bubble content. And the produced | generated micro nano bubble containing water is introduce | transduced into the micro nano bubble adhesion tank, and the micro nano bubble in the said micro nano bubble containing water is made to adhere to the microorganisms in the introduced microorganism sludge. Therefore, microorganisms attached with micro-nano bubbles are activated, and it is possible to effectively perform nitrification treatment in the nitrification tank in the subsequent stage, denitrification treatment in the denitrification tank, and decomposition treatment of the hydrogen donor in the re-aeration tank. become.

  At that time, the nitrification tank and the denitrification tank are filled with a filler for attaching micro-nano bubbles. Therefore, the micro-nano bubbles adhering to the microorganisms can be further adhered to the filler for adhering the micro-nano bubbles to further stabilize (fix) the microorganisms, and the nitrification treatment, denitrification treatment, and hydrogen donor decomposition The processing can be performed more effectively.

Further, the nitrification tank and the denitrification tank, which has a higher water depth 7m, the water to be treated nitrification tank bottom inlet and denitrification lower inlet pipe is introduced, the bottom of the nitrification tank and the denitrification tank It is designed to be discharged. Therefore, the micro / nano bubbles introduced in the lowermost part of the nitrification tank and the denitrification tank are shrunk by water pressure and become smaller in size. Therefore, the micro-nano bubbles attached to the microorganism are more easily used by the microorganism, the micro-nano bubbles not attached to the microorganism are easily attached to the microorganism, and the micro-nano bubbles not attached to the filler are attached to the filler. It becomes easy to do.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
The microbial sludge introduced into the micro / nano bubble adhesion tank is introduced from the re-aeration tank.

  According to this embodiment, the microorganism after the treated water is separated in the re-aeration tank can be used as the microorganism to which the micro-nano bubble is adhered in the micro-nano bubble adhesion tank. Furthermore, the balance between the aerobic property of the nitrification tank and the anaerobic property of the denitrification tank can be adjusted by controlling the amount of microbial sludge introduced from the re-aeration tank.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
The micro / nano bubble generation tank has two types of micro / nano bubble generators, an underwater pump type micro / nano bubble generator and a swirl type micro / nano bubble generator.

  According to this embodiment, a large amount of micro-nano bubbles are generated by the submerged pump type micro-nano bubble generator which generates a large amount of micro-nano bubbles which is larger in size than a swirling flow type micro-nano bubble generator. Let After that, by introducing the liquid containing the slightly larger micro-nano bubbles into the above-mentioned swirl type micro-nano bubble generator, a large amount of micro-nano bubbles having a larger proportion of nano-bubbles than micro-bubbles can be generated. it can.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
The micro / nano bubble generating tank is equipped with a micro / nano bubble generating auxiliary agent adding device for adding a micro / nano bubble generating auxiliary agent.

  According to this embodiment, a large amount of micro / nano bubbles can be easily generated by adding the micro / nano bubble generation aid to the micro / nano bubble generation tank using the micro / nano bubble generation aid addition device.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
The above micro / nano bubble generation auxiliary agent adding device is:
A micro / nano bubble generation aid tank for storing the micro / nano bubble generation aid;
A micro-nano bubble generation aid tank metering pump that transports the micro-nano bubble generation aid in the micro-nano bubble generation aid tank to the micro-nano bubble generation tank in a fixed amount.

  According to this embodiment, by controlling the transport amount of the micro-nano bubble generation aid by the micro-nano bubble generation aid tank metering pump, maintaining the generation of the optimum amount of micro-nano bubbles in the micro-nano bubble generation tank Is possible.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
A turbidimeter installed in the micro / nano bubble generation tank and measuring the turbidity of the water to be treated in the micro / nano bubble generation tank,
Based on the measurement result by the turbidimeter, the transport amount of the micro / nano bubble generation aid by the micro / nano bubble generation aid tank metering pump is controlled so that the measurement result by the turbidimeter has a predetermined turbidity. And a turbidity controller.

  When the amount of micro-nano bubbles generated in the micro-nano bubble generation tank is small, the turbidity of the water to be treated in the micro-nano bubble generation tank is low, and when the amount of micro-nano bubbles is large, the turbidity is high. Therefore, the generated amount of micro / nano bubbles can be measured by the turbidimeter.

  According to this embodiment, based on the measurement result by the turbidimeter, the turbidity controller controls the micro / nano bubble generation aid tank metering pump so that the measurement result has a predetermined turbidity. The addition amount of the micro / nano bubble generation aid can be controlled so that the generation amount of the micro / nano bubbles in the micro / nano bubble generation tank becomes a predetermined generation amount.

  That is, according to this embodiment, an appropriate amount of micro / nano bubbles can be generated by adding an optimum amount of micro / nano bubble generation aid based on the measurement result by the turbidimeter.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
A catalytic oxidation tank, a precipitation tank, a rapid filter and an activated carbon adsorption tower are installed after the re-aeration tank.

  According to this embodiment, advanced treatment centering on organic matter in the water to be treated can be performed in the subsequent stage of the re-aeration tank. Therefore, a convenient nitrogen-containing wastewater treatment apparatus can be provided when used in places where the treatment water discharge conditions are severe or when the treated water is reused.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
A second micro / nano bubble generation tank, a rapid filter, and an activated carbon adsorption tower are installed after the re-aeration tank.

  According to this embodiment, the second micro / nano bubble generation tank can further generate micro / nano bubbles after the re-aeration tank. Therefore, the microorganisms in the treated water in the re-aeration tank are activated by the adhesion of the generated micro-nano bubbles, and the organic matter adhering to the rapid filter and the organic matter adsorbed by the activated carbon of the activated carbon adsorption tower are activated by the activated microorganisms. It is decomposed efficiently. As a result, clogging of the rapid filter can be prevented. Furthermore, the number of regenerations per year in the activated carbon of the activated carbon adsorption tower can be reduced.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
The nitrogen-containing wastewater introduced into the nitrification tank is a surfactant-containing nitrogen wastewater.

  According to this embodiment, the generation efficiency of the micro / nano bubbles in the micro / nano bubble generation tank is remarkably improved by the surfactant in the nitrogen waste water containing the surfactant. Therefore, a large amount of micro / nano bubbles are generated in the micro / nano bubble generation tank and adhered to the microorganism, the microorganism is further activated, and the surfactant in the water to be treated is efficiently decomposed by the activated microorganism. Can do.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
The second micro / nano bubble generation tank, the precipitation tank, the third micro / nano bubble generation tank, the rapid filter and the activated carbon adsorption tower are installed after the re-aeration tank.
The nitrogen-containing wastewater introduced into the nitrification tank is a surfactant-containing nitrogen wastewater.

  According to this embodiment, three micro / nano bubble generation tanks are installed. Accordingly, three-stage treatment with micro-nano bubbles is performed, and microbial decomposition can be performed also on nitrogen wastewater containing an organic fluorine-based surfactant.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
A line mixer type air diffuser is installed in the micro / nano bubble adhesion tank, the nitrification tank, and the re-aeration tank.

  According to this embodiment, fine air can be generated by the line mixer type diffuser as compared with a normal porous diffuser. Therefore, in the micro / nano bubble adhesion tank, the nitrification tank, and the re-aeration tank, the water to be treated can be efficiently stirred by the fine air. Furthermore, in the nitrification tank, more contracted fine air can be generated and used by the microorganisms by a combination of the water pressure in the water tank having a water depth of 7 m or more and the fine air.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
The denitrification tank lower introduction pipe is composed of a first denitrification tank lower introduction pipe, a second denitrification tank lower introduction pipe, and two denitrification tank lower introduction pipes,
The denitrification tank has a first denitrification tank in which the first denitrification tank lower introduction pipe is installed , the introduction port communicating with the upper part of the nitrification tank, and the introduction port communicated with the upper part of the first denitrification tank. The second denitrification tank lower introduction pipe is composed of two denitrification tanks and the second denitrification tank,
The nitrification tank is equipped with a line mixer type air diffuser,
The re-aeration tank includes a first pump for transferring microbial sludge in the re-aeration tank to the micro-nano bubble adhesion tank, and a second pump for transferring treated water in the re-aeration tank to the micro-nano bubble generation tank. Is installed,
A first oxidation-reduction potentiometer installed in the first denitrification tank and measuring the oxidation-reduction potential in the first denitrification tank;
Based on the measurement result of the first oxidation-reduction potentiometer, a first oxidation-reduction potential controller that controls the pumping amount of the blower that pumps air to the line mixer type diffuser of the nitrification tank;
A second oxidation-reduction potentiometer installed in the second denitrification tank and measuring the oxidation-reduction potential in the second denitrification tank;
And a second oxidation-reduction potential controller for controlling the transfer amounts of the first pump and the second pump of the re-aeration tank based on the measurement result of the second oxidation-reduction potentiometer.

  According to this embodiment, based on the measurement result of the first oxidation-reduction potentiometer installed in the first denitrification tank, the first oxidation-reduction potential controller uses the air in the line mixer type diffuser of the nitrification tank. The pumping amount of the blower that pumps the pump is controlled. Moreover, based on the measurement result of the 2nd oxidation-reduction potentiometer installed in the 2nd denitrification tank, the microorganisms sludge containing the micro-nano bubble in the said re-aeration tank is made into the said micro-nano bubble adhesion tank by the 2nd oxidation-reduction potential controller. The amount of transfer between the first pump that transfers to the micro-nano bubble generation tank and the second pump that transfers the treated water containing the micro-nano bubbles in the re-aeration tank is controlled. Thus, a balanced oxidation-reduction potential state is maintained in the nitrification tank and the first and second denitrification tanks.

  Therefore, it is possible to achieve a balance between the aerobic property of the nitrification tank and the anaerobic characteristics of the first and second denitrification tanks, thereby improving the total nitrogen removal rate. That is, according to this embodiment, optimal operation management of the present nitrogen-containing wastewater treatment apparatus becomes possible.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
The surfactant in the surfactant-containing nitrogen waste water is an organic fluorine-based compound.

  According to this embodiment, the micro-nano bubbles generated in the micro-nano bubble generation tank can be attached to the microorganisms in the micro-nano bubble adhesion tank, and the microorganisms can be activated efficiently. Therefore, the organofluorine compound in the surfactant-containing nitrogen waste water can be decomposed by the activated microorganism.

In the nitrogen-containing wastewater treatment apparatus of one embodiment,
The organic fluorine-based compound is perfluorooctane sulfonic acid or perfluorooctanoic acid.

  According to this embodiment, the micro-nano bubbles generated in the micro-nano bubble generation tank can be attached to the microorganisms in the micro-nano bubble adhesion tank, and the microorganisms can be activated efficiently. Therefore, perfluorooctanesulfonic acid or perfluorooctanoic acid in the surfactant-containing nitrogen waste water can be decomposed by the activated microorganism.

The nitrogen-containing wastewater treatment method of the present invention is
The micro / nano bubble generated in the micro / nano bubble generation tank having the micro / nano bubble generator is attached to the microorganisms in the introduced microbial sludge in the micro / nano bubble adhesion tank,
The microbial sludge containing the micro-nano bubbles attached to the microorganisms and the nitrogen-containing wastewater from the outside are introduced into the lowermost part of the nitrification tank having a depth of 7 m or more and filled with a filler for attaching micro-nano bubbles. Then, nitrification treatment is performed on the introduced nitrogen-containing wastewater,
Water to be treated that has been nitrified by the nitrification tank has a water depth of 7 m or more, and is introduced into the lowermost part of the denitrification tank filled with the filler for attaching micro-nano bubbles, and a hydrogen donor is added, Perform denitrification treatment on the treated water introduced above,
The water to be treated, which has been denitrified by the denitrification tank, is introduced into a re-aeration tank having an aeration device, and the hydrogen donor in the water to be treated added excessively in the denitrification tank is microbially decomposed. It is characterized by that.

  According to the above configuration, the micro / nano bubbles generated in the micro / nano bubble generation tank are attached to the microorganisms in the introduced microbial sludge in the micro / nano bubble adhesion tank. Therefore, microorganisms attached with micro-nano bubbles are activated, and it is possible to effectively perform nitrification treatment in the nitrification tank in the subsequent stage, denitrification treatment in the denitrification tank, and decomposition treatment of the hydrogen donor in the re-aeration tank. become.

  At that time, the nitrification tank and the denitrification tank are filled with a filler for attaching micro-nano bubbles. Therefore, the micro-nano bubbles adhering to the microorganisms can be further adhered to the filler for adhering the micro-nano bubbles to further stabilize (fix) the microorganisms, and the nitrification treatment, denitrification treatment, and hydrogen donor decomposition The processing can be performed more effectively.

  Furthermore, the nitrification tank and the denitrification tank have a water depth of 7 m or more, and the water to be treated is introduced into the lowermost part. Therefore, the micro / nano bubbles introduced in the lowermost part of the nitrification tank and the denitrification tank shrink by water pressure and become smaller in size. Therefore, the micro-nano bubbles attached to the microorganism are more easily used by the microorganism, the micro-nano bubbles not attached to the microorganism are easily attached to the microorganism, and the micro-nano bubbles not attached to the filler are attached to the filler. It becomes easy to do.

In the nitrogen-containing wastewater treatment method of one embodiment,
The nitrification tank is composed of two tanks, a first nitrification tank having a water depth of 7 m or more and a second nitrification tank having a water depth of 7 m or more,
The denitrification tank is composed of two tanks, a first denitrification tank having a water depth of 7 m or more and a second denitrification tank having a water depth of 7 m or more,
The first nitrification tank, the second nitrification tank, the first denitrification tank, and the second denitrification tank are provided with a lower introduction pipe having an inlet at the upper part and a discharge hole at the lower part,
The first nitrification tank and the second nitrification tank, the second nitrification tank and the first denitrification tank, and the first denitrification tank and the second denitrification tank are connected to each other in series by the lower introduction pipe. And
The microbial sludge introduced into the first nitrification tank and the nitrogen-containing waste water, the second nitrification tank, the first denitrification tank, and the water to be treated from the preceding tank introduced into the second denitrification tank, It is introduced from the introduction port of the lower introduction pipe, flows down in the lower introduction pipe, and is introduced from the discharge hole of the lower introduction pipe to the lowermost part of the nitrification tank and the denitrification tank.

  According to this embodiment, the present nitrogen-containing wastewater treatment apparatus is composed of several water tanks and is sequentially treated three-dimensionally and in the entire water tank, so that the nitrification treatment and the denitrification treatment are surely performed. Done.

  As apparent from the above, according to the present invention, the micro / nano bubbles generated in the micro / nano bubble generation tank are adhered to the microorganisms in the introduced microbial sludge in the micro / nano bubble adhesion tank. Therefore, the microorganisms to which the micro / nano bubbles are attached are activated, and the nitrification treatment in the subsequent nitrification tank, the denitrification treatment in the denitrification tank, and the hydrogen donor decomposition treatment in the re-aeration tank can be performed effectively. .

  At that time, the nitrification tank and the denitrification tank are filled with a filler for attaching micro-nano bubbles. Therefore, the micro-nano bubbles adhering to the microorganisms can be further adhered to the filler for adhering the micro-nano bubbles to further stabilize (fix) the microorganisms, and the nitrification treatment, denitrification treatment, and hydrogen donor decomposition The processing can be performed more effectively.

  Further, the nitrification tank and the denitrification tank have a water depth of 7 m or more, and the water to be treated is introduced into the lowermost part. Therefore, the micro / nano bubbles introduced in the lowermost part of the nitrification tank and the denitrification tank shrink with water pressure and become smaller in size. Therefore, the micro-nano bubbles attached to the microorganisms are more easily utilized by the microorganisms, the micro-nano bubbles not attached to the microorganisms are easily attached to the microorganisms, and the micro-nano bubbles not attached to the fillers are used as the filler. It can be easily adhered.

  As described above, according to the present invention, it is possible to provide a nitrogen-containing wastewater treatment apparatus and a nitrogen-containing wastewater treatment method capable of stabilizing and activating microorganisms and improving the treatment capacity of the microorganisms.

  Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

-1st Embodiment FIG. 1: is a figure which shows the structure in the nitrogen containing waste water treatment equipment of this Embodiment. The nitrogen-containing wastewater treatment apparatus of this embodiment is mainly composed of a micro / nano bubble generation tank 1, a micro / nano bubble adhesion tank 2, a nitrification tank 3, a denitrification tank 4 and a re-aeration tank 5 to sludge. Further, the nitrification tank 3 includes a first nitrification tank 6 and a second nitrification tank 7, and the denitrification tank 4 includes a first denitrification tank 8 and a second denitrification tank 9. As a measuring instrument, a turbidimeter 10 is installed in the micro / nano bubble generation tank 1, a first oxidation-reduction potentiometer 11 is installed in the first denitrification tank 8, and a second oxidation-reduction potentiometer 12 is installed in the second denitrification tank 9.

  Nitrogen-containing wastewater such as domestic wastewater and factory wastewater as inflow water is introduced into the first nitrification tank 6 filled with the polyvinylidene chloride filler 13 as the filler for attaching micro-nano bubbles. A representative component in the nitrogen-containing wastewater is ammoniacal nitrogen. In addition to the nitrogen-containing wastewater, sludge water is introduced into the first nitrification tank 6. Here, the above “sludge water” is sludge water that has flowed out of the micro-nano bubble adhesion tank (hereinafter simply referred to as “micro-nano bubble adhesion tank”) 2 to the sludge. It is adhering sludge water.

The nitrogen-containing wastewater is introduced from the uppermost part of the lower introduction pipe (nitrification tank lower introduction pipe) 14 of the first nitrification tank 6 together with the sludge water, and is discharged into the first nitrification tank 6 from the lowermost part. . In that case, the lower introduction pipe 14 is devised so that the water to be treated is evenly discharged from the lowermost part of the first nitrification tank 6. Specifically, as shown in FIG. 1, the lower introduction pipe 14 is formed in an L shape, and a plurality of holes 15 are provided in the lowermost piping part. The nitrogen-containing waste water and the sludge water are discharged from a large number of holes 15 provided at the lowermost part of the lower introduction pipe 14.

  Thus, the micro-nano bubbles discharged together with the sludge water from the lowermost part of the lower introduction pipe 14 and having a relatively large size that is not attached to microorganisms in the sludge water have a water depth in the first nitrification tank 6. Since it is a water tank of 7 m or more, it shrinks and becomes smaller due to water pressure, changes its characteristics, and is easily attached by the microorganisms and the polyvinylidene chloride filler 13. Further, since the micro / nano bubbles are reduced, they are easily utilized (consumed) by microorganisms such as nitrifying bacteria.

  The ammonia nitrogen, which is a representative component in the nitrogen-containing wastewater, is partially oxidized to nitrate nitrogen by the microorganisms that have propagated and activated on the polyvinylidene chloride filler 13 and change into nitrate nitrogen.

  Below the middle of the first nitrification tank 6, a line mixer type air diffuser 16 and an air supply unit 17 for supplying air to the line mixer type air diffuser 16 are provided. Air is pumped from a blower 18 installed outside the first nitrification tank 6.

  Here, the line mixer type air diffuser 16 is an air diffuser capable of generating finer air than an ordinary porous air diffuser. It is comprised from the site | part which has many protrusions which crush a liquid multiphase flow finely. And this line mixer type air diffuser 16 functions as an air diffuser even in microbial sludge, and can generate fine air without clogging the sludge.

  The fine air generated by the line mixer-type air diffuser 16 has a deep water depth in the first nitrification tank 6, and therefore becomes finer due to water pressure, unlike the conditions in a normal water tank having a water depth of 4 m to 5 m. The dissolution efficiency in water is improved.

The second nitrification tank 7 is provided with a lower introduction pipe (nitrification tank lower introduction pipe) 14 having the same structure as the lower introduction pipe 14 of the first nitrification tank 6. However, the uppermost end of the lower introduction pipe 14 of the second nitrification tank 7 communicates with the upper part of the first nitrification tank 6. And the to-be-processed water processed by the 1st nitrification tank 6 as mentioned above overflows in the lower introduction pipe 14 of the 2nd nitrification tank 7 from the upper part of the 1st nitrification tank 6, and this lower introduction pipe 14 is discharged into the second nitrification tank 7 from the lowermost part.

  As described above, in the first nitrification tank 6, most of the ammonia nitrogen in the water to be treated is oxidized to nitrate nitrogen, but it is not perfect. Therefore, in the second nitrification tank 7, as in the case of the first nitrification tank 6, the remaining ammoniacal nitrogen is oxidized to nitrate nitrogen. As a result, the oxidation of ammonia nitrogen to nitrate nitrogen is reliably performed. In addition, since the equipment content of the 2nd nitrification tank 7 is the same as the equipment content of the 1st nitrification tank 6, the same number is attached | subjected in FIG. 1, and description is abbreviate | omitted.

The first denitrification tank 8 is provided with a lower introduction pipe (first denitrification tank lower introduction pipe) 14 having the same structure as the lower introduction pipe 14 of the second nitrification tank 7. The upper end communicates with the upper part of the second nitrification tank 7. And the to-be-processed water which came out of the 2nd nitrification tank 7 overflows in the lower introductory pipe 14 of the 1st denitrification tank 8, and the 1st denitrification tank from many holes 15 provided in the lowest part of the lower introductory pipe 14 8 is discharged.

  The first denitrification tank 8 is provided with a polyvinylidene chloride filler 13 and a first oxidation-reduction potentiometer 11 as the filler for attaching micro-nano bubbles. A first oxidation-reduction potential controller 19 that adjusts the amount of air in the nitrification tank 3 is installed outside the first denitrification tank 8. And by controlling the blower 18 with an inverter by a control signal from the first oxidation-reduction potential controller 19, the air quantity is controlled by controlling the blower 18 and the anaerobic property in the denitrification tank 4, that is, the nitrification tank 3 By balancing the amount of air with the denitrification tank 4, it is prevented that the amount of air in the nitrification tank 3 becomes too large to maintain the anaerobic state of the denitrification tank 4. The nitrate nitrogen is reduced by the anaerobic microorganisms propagated in the polyvinylidene chloride filling 13 in the first denitrification tank 8 to form nitrogen gas, and nitrogen is removed by going out into the air.

  The processing status in the first denitrification tank 8 will be described in detail as follows. That is, the first denitrification tank 8 is divided into “a denitrification tank main body as an anaerobic microorganism adhesion tank having a water depth of 7 m or more and provided with a filler for attaching micro-nano bubbles” and “a lower part installed in the denitrification tank main body”. And an introduction pipe 14 ”. Then, the water to be treated is discharged from the hole 15 of the lower introduction pipe 14 to the lower part of the first denitrification tank 8. Thus, the size of the micro-nano bubbles remaining in the first denitrification tank 8 is reduced by contraction by water pressure, and the micro-nano bubbles reduced by a large amount of anaerobic microorganisms are consumed. Is converted to anaerobic in a short time to enhance the function of anaerobic microorganisms.

  Next, the to-be-processed water which flowed out from the said 1st denitrification tank 8 is introduce | transduced into the 2nd denitrification tank 9 which has the same structure as the 1st denitrification tank 8, and the process similar to the case of the 1st denitrification tank 8 is performed. Is called. However, the sludge pump 21 and the first submerged membrane pump 22 installed in the re-aeration tank 5 are inverter-controlled by a control signal from the second oxidation-reduction potential controller 20, and the micro / nano bubble generation tank 1 and the micro The transfer amount of water containing micro / nano bubbles to the nano bubble adhesion tank 2 is controlled. In this way, the balance between the nitrification tank 3 and the denitrification tank 4 is achieved.

  Specifically, when the transfer amount between the sludge pump 21 and the first submerged membrane pump 22 is large, the sludge-containing water containing micro-nano bubbles increases in the first nitrification tank 6 and is dissolved by the micro-nano bubbles. Oxygen increases, and as a result, the oxidation of the first nitrification tank 6 is promoted. However, if the sludge-containing water containing too much micro-nano bubbles increases, the machineability is maintained up to the second denitrification tank 9, so the transfer amount between the sludge pump 21 and the first submerged membrane pump 22 is controlled.

  That is, if the anaerobic property of the second denitrification tank 9, that is, the oxidation-reduction potential value of the second oxidation-reduction potential controller 20 cannot be properly maintained, the micro-nano bubbles to the micro-nano bubble generation tank 1 and the micro-nano bubble adhesion tank 2 are lost. Reduce the amount of water contained. If it does so, since the micro nano bubble containing water will decrease in the 1st nitrification tank 6, as a result, it will be in the state which can maintain the anaerobic property of the denitrification tank 4 which is an anaerobic tank. Note that methanol or the like as a hydrogen donor is added from the hydrogen donor tank 23 to the first denitrification tank 8 and the second denitrification tank 9 by a hydrogen donor tank metering pump 24.

  Next, the water to be treated is introduced into the re-aeration tank 5, and methanol as a hydrogen donor in the water to be treated added excessively in the denitrification tank 4 is microbially decomposed. In this re-aeration tank, in addition to the sludge pump 21 and the first submerged membrane pump 22, a second submerged membrane pump 25 is installed. Then, the treated water is obtained by solid-liquid separation of the microbial sludge and the treated water by the second submerged membrane pump 25 and the submerged membrane 26. The re-aeration tank 5 is also provided with a line mixer type air diffuser 16 and an air supply unit 17 for supplying air to the line mixer type air diffuser 16. And air is pumped from the blower 27 to the air supply unit 17. Here, the “submerged membrane” refers to a membrane present in the liquid.

  A part of the air from the blower 27 is supplied to a line mixer type air diffuser 28 installed in the micro / nano bubble adhering tank 2. The purpose of supplying air to the micro / nano bubble adhesion tank 2 is to stir the tank.

  As described above, the re-aeration tank 5 is provided with the sludge pump 21 and the first submerged membrane pump 22. The sludge pump 21 introduces the microbial sludge containing the micro / nano bubbles in the re-aeration tank 5 into the micro / nano bubble adhering tank 2 via the sludge pipe 29. On the other hand, the first submerged membrane pump 22 transfers a part of the treated water (including micro-nano bubbles) from the submerged membrane 26 to the micro / nano bubble generating tank 1 via the treated water pipe 30. The remaining treated water from the submerged membrane 26 is discharged out of the system of the wastewater treatment apparatus via the treated water piping 31 by the second submerged membrane pump 25.

  In the micro / nano bubble generation tank 1, an underwater pump type micro / nano bubble generator 32, a non-submersible pump type micro / nano bubble generator 33, and a turbidimeter 10 as a measuring instrument are installed. The micro / nano bubble generation tank 1 is a water tank for efficiently generating micro / nano bubbles using treated water transferred from the re-aeration tank 5 by the first submerged membrane pump 22.

  Specifically, the micro / nano bubble generation tank 1 is a water tank made of various materials such as plastic, stainless steel, and vinyl chloride. In addition, what is necessary is just to select the material of a water tank suitably according to the property of a liquid. And, as described above, the submersible pump type micro / nano bubble generator 32 and the non-submersible pump type swirl type micro / nano bubble generator 33 are installed inside the micro / nano bubble generation tank 1, respectively. A water stream 35 is generated. Then, the treated water from the first submerged membrane pump 22 flows into the micro / nano bubble generation tank 1 from the inflow pipe 36. A turbidimeter 10 is installed inside the micro / nano bubble generation tank 1. The reason for installing the turbidimeter 10 is to measure the occurrence of micro / nano bubbles with a meter.

  That is, when many micro / nano bubbles are generated in the micro / nano bubble generation tank 1, the treated water tends to become white and turbidity increases. Therefore, the turbidimeter 10 shows a high value. On the other hand, when the micro / nano bubbles are not sufficiently generated, the turbidity tends to decrease. Therefore, the turbidimeter 10 will show a low value.

  Therefore, the signal from the turbidimeter 10 is transmitted to the turbidity controller 40 through the signal line 39, and the micro-nano bubble generation aid tank determination is performed by the control signal from the turbidity controller 40 through the signal line 41. The pump 42 is controlled by an inverter. Thus, the addition amount of the micro / nano bubble generation aid from the micro / nano bubble generation aid tank 43 to the micro / nano bubble generation tank 1 is controlled so that the optimum addition amount is obtained. An appropriate amount of micro / nano bubbles is generated depending on the optimum amount of the micro / nano bubble generation aid. That is, in the present embodiment, the micro / nano bubble generating auxiliary agent adding device is composed of the micro / nano bubble generating auxiliary agent tank metering pump 42 and the micro / nano bubble generating auxiliary agent tank 43.

  More specifically, when the value of the turbidimeter 10 is low, the amount of micro / nano bubbles generated is small, so that the number of revolutions of the motor is increased by the inverter control of the micro / nano bubble generation aid tank metering pump 42 and the micro / nano bubbles are generated. Add a lot of generation aid. In this way, a large number of micro / nano bubbles are generated, and the numerical value of the turbidimeter 10 is controlled to be high. Further, when the numerical value of the turbidimeter 10 is high, micro-nano bubbles are sufficiently generated. Therefore, the micro-nano bubble generation aid is reduced by controlling the inverter of the micro-nano bubble generation aid tank metering pump 42 to reduce the motor rotation speed. Reduce the amount of added. Even in this case, the micro-nano bubbles are operating in a sufficiently generated state. In this way, the running cost can be reduced by controlling the amount of the micro / nano bubble generation aid added.

  The micro / nano bubble generation aids include various surfactants with good microbial degradability, various alcohols, etc., and may be appropriately selected depending on the purpose.

  The submersible pump type micro / nano bubble generator 32 is supplied with air from a blower 38 connected via an air pipe 37. The submersible pump type micro / nano bubble generator 32 generates micro bubbles by cutting the air supplied from the blower 38 by rotating at high speed. Then, the water flow 34 is generated by discharging the microbubbles from the submersible pump type micro / nano bubble generator 32. After that, some of the microbubbles contract with time and become nanobubbles.

  On the other hand, the swirling flow type micro / nano bubble generator 33 is linked with a circulation pump 44 by piping, and the circulation pump 44 supplies high-pressure circulating water to the swirling flow type micro / nano bubble generator 33. The swirling flow type micro / nano bubble generator 33 is provided with an air intake pipe 45 for drawing air and a needle valve 46 for adjusting the amount of air.

  As described above, the micro-nano bubbles are sufficiently contained in the treated water in the micro-nano bubble generation tank 1, and then the micro-nano bubble-containing liquid is introduced into the micro-nano bubble adhesion tank 2 which is the next step through the outflow pipe 47.

  In the micro / nano bubble adhering tank 2, the micro / nano bubble-containing liquid from the micro / nano bubble generating tank 1 containing a large amount of micro / nano bubbles of a desired size and the microbial sludge from the sludge pump 21 are a line mixer type air diffuser. When a large amount of microbubbles are discharged from the device 28, the mixture is vigorously mixed and stirred. As a result, the micro-nano bubbles from the micro-nano bubble generation tank 1 adhere to the microorganisms in the microbial sludge from the sludge pump 21, and the microorganisms are activated. As described above, although the micro / nano bubbles adhere to the microorganism, there are relatively large micro bubbles that do not adhere to the microorganism. In addition, a large amount of large microbubbles are generated by the line mixer type diffuser 28.

  As described above, the micro-nano bubble adhering tank 2 includes a micro-nano bubble having a small size attached to the microorganism, a micro-nano bubble having a relatively large size not attached to the microorganism, and a line mixer-type air diffuser 28. There are microbubbles of various sizes, with the generated large size microbubbles. Then, all the microbubbles of various sizes are introduced from the micro / nanobubble adhering tank 2 to the upper end of the lower introduction pipe 14 of the first nitrification tank 6 through the sludge pipe 48, and at the lowermost part of the lower introduction pipe 14. It is discharged from the provided hole 15 to the lower part of the first nitrification tank 6 and is effectively used for nitrification treatment.

  As described above, in the present embodiment, the nitrification layer 3 is constituted by the first nitrification layer 6 and the second nitrification layer 7, and the water depth in the first nitrification layer 6 is set to 7 m or more, and the first nitrification layer is formed. A discharge portion of the lower introduction pipe 14 is disposed below the layer 6. Therefore, at the bottom of the first nitrification layer 6, the relatively large size microbubbles not attached to the microorganisms and the microbubbles as fine air derived from the line mixer-type air diffuser 28 are contracted by water pressure, and the microorganisms And it becomes a size that is easy to adhere to the filler for attaching micro-nano bubbles. As a result, the microbubbles not only adhere to the microorganisms, but also adhere to the filler for adhering the micronanobubbles in a state of adhering to the microorganisms, and are effective in activating and stabilizing (fixing) the microorganisms. It becomes.

  The micro / nano bubble generation tank 1 is provided with a submersible pump type micro / nano bubble generator 32 and a non-submersible pump type swirl type micro / nano bubble generator 33. In that case, the micro-nano bubbles generated from the swirling flow type micro-nano bubble generator 33 are smaller in size and generated less than the micro-nano bubbles generated from the submerged pump type micro-nano bubble generator 32. And it is known that the finer the bubble, the longer it will last in the liquid, and the more effective the action against microorganisms.

  Therefore, in the present embodiment, first, a large amount of slightly larger micro / nano bubbles are generated by the submersible pump type micro / nano bubble generator 32, and then the liquid containing the slightly larger micro / nano bubbles is swirled. By introducing the micro-nano bubble generator 33, micro-nano bubbles having a larger proportion of nano-bubbles than micro-bubbles are generated. Note that the submersible pump type micro / nano bubble generator 32 is not limited to the manufacturer, and specifically, a submersible pump type micro / nano bubble generator 32 is used. The swirling flow type micro / nano bubble generator 33 uses a product of Nano Planet Research Laboratory. Many products from other manufacturers are also on sale, but you can select them according to your purpose.

  Here, three types of bubbles will be described. First, a normal bubble (bubble) rises in the water and pops off on the surface and disappears. In contrast, microbubbles are fine bubbles having a diameter of 1 micron (μm) to 50 microns (μm), shrink in water, and eventually disappear (completely dissolve). Nanobubbles are fine bubbles (100 nm to 200 nm having a diameter of 1 micron or less) that are even smaller than the above-described microbubbles, and can exist in water indefinitely. A micro nano bubble is a bubble in which micro bubbles and nano bubbles are mixed. The line mixer type diffuser 28 cannot generate nanobubbles, but can generate a large amount of microbubbles.

-2nd Embodiment FIG. 2: is a figure which shows the structure in the nitrogen containing waste water treatment equipment of this Embodiment. The nitrogen-containing wastewater treatment apparatus shown in FIG. 2 is that the line mixer-type air diffuser 28 installed in the micro / nano bubble adhering tank 2 of the first embodiment shown in FIG. Different. Since the other configuration is the same as that of the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG. 1, the same reference numerals are given and detailed description is omitted.

  In the nitrogen-containing wastewater treatment apparatus, the micro / nano bubble adhering tank 2 is not provided with a line mixer type air diffuser that diffuses the air pumped from the blower 27, and instead the air pumped from the blower 27. An air diffuser 51 is installed to diffuse the air. Therefore, in the micro / nano bubble adhering tank 2, the sludge containing microorganisms from the re-aeration tank 5 and the micro / nano bubble-containing water from the micro / nano bubble generating tank 1 are fine micro bubbles discharged from the line mixer type diffuser. Instead, they are agitated and mixed by the air discharged from the existing air diffuser 51.

  When the purpose of stirring and mixing is the purpose, the air discharged from the air diffuser 51 is sufficient as in the present embodiment. Therefore, in the present embodiment, the initial cost can be reduced by the amount not using the line mixer type diffuser in the micro / nano bubble adhering tank 2 as compared with the case of the first embodiment. It is.

-3rd Embodiment FIG. 3: is a figure which shows the structure in the nitrogen containing waste water treatment equipment of this Embodiment. The nitrogen-containing wastewater treatment apparatus shown in FIG. 3 is different from the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG. 1 in that the nitrogen-containing wastewater is introduced not into the first nitrification tank 6 but into the micro / nanobubble adhesion tank 2. It differs in the point to do. In addition, since the other structure is the same as the nitrogen-containing waste water treatment apparatus of the said 1st Embodiment shown in FIG. 1, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  In the nitrogen-containing wastewater treatment apparatus, nitrogen-containing wastewater is introduced into the micro / nano bubble adhesion tank 2. Therefore, in the micro / nano bubble adhering tank 2, the nitrogen-containing waste water, the microbial sludge from the sludge pump 21 and the micro / nano bubble-containing water from the micro / nano bubble generating tank 1 are mixed and stirred. Therefore, it is possible to mix and agitate the micro-nano bubbles, the microorganisms, and the nitrogen-containing wastewater from an early point in time, and an improvement in treatment efficiency due to the initial adsorption of the microorganism sludge to the nitrogen-containing wastewater can be expected.

  That is, according to this Embodiment, the processing performance of a nitrogen-containing waste water treatment apparatus can be improved.

-4th Embodiment FIG. 4: is a figure which shows the structure in the nitrogen containing waste water treatment equipment of this Embodiment. The nitrogen-containing wastewater treatment apparatus shown in FIG. 4 is different from the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG. 1 in that the nitrogen-containing wastewater is introduced not into the first nitrification tank 6 but into the micro / nano bubble generation tank 1. It differs in the point to do. Other configurations are the same as those of the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG.

  In this nitrogen-containing wastewater treatment apparatus, nitrogen-containing wastewater is introduced from the inflow pipe 52 into the micro / nano bubble generating tank 1. Therefore, the conditions for generating micro / nano bubbles are the best conditions. The reason is because it has been empirically known that the generation state of micro-nano bubbles is better in the raw water than in the treated water.

  That is, according to the present embodiment, a large amount of micro / nano bubbles can be formed using components in the nitrogen-containing wastewater, which can be used for the treatment of the nitrogen-containing wastewater.

-5th Embodiment FIG. 5: is a figure which shows the structure in the nitrogen containing waste water treatment equipment of this Embodiment. The nitrogen-containing wastewater treatment apparatus shown in FIG. 5 differs from the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG. 1 in the subsequent stage of the re-aeration tank 5 in the contact oxidation tank 53, the precipitation tank 54, and the rapid filter 55. And the activated carbon adsorption tower 56 are different in that they are arranged in this order. Other configurations are the same as those of the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG.

  In this nitrogen-containing wastewater treatment apparatus, as described above, the contact oxidation tank 53, the precipitation tank 54, the rapid filter 55, and the activated carbon adsorption tower 56 are arranged in this order after the re-aeration tank 5. Therefore, it is possible to perform advanced treatment of the water to be treated in the re-aeration tank 5 and the subsequent steps.

  That is, according to this embodiment, it is possible to provide a nitrogen-containing wastewater treatment apparatus that is convenient when used in places where the discharge conditions of treated water are considerably severe or when the treated water is reused.

-6th Embodiment FIG. 6: is a figure which shows the structure in the nitrogen containing waste water treatment equipment of this Embodiment. The nitrogen-containing wastewater treatment apparatus shown in FIG. 6 is different from the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG. 1 in that a submersible pump type micro / nano bubble generator 32 is installed in the rear stage of the re-aeration tank 5. The 2 micro / nano bubble generation tank 57, the rapid filter 55 and the activated carbon adsorption tower 56 are arranged in this order, and the difference is that air is supplied from the blower 38 to the submersible pump type micro / nano bubble generator 32. Other configurations are the same as those of the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG. Also, the submersible pump type micro / nano bubble generator 32 and the blower 38 are the same as those in the first embodiment shown in FIG. Moreover, since the rapid filter 55 and the activated carbon adsorption tower 56 are the same as the case of the said 5th Embodiment shown in FIG. 5, the same code | symbol is attached | subjected.

  In the present nitrogen-containing wastewater treatment apparatus, as described above, the second micro / nano bubble generation tank 57, the rapid filter 55, and the activated carbon adsorption tower in which the submersible pump type micro / nano bubble generator 32 is installed in the rear stage of the re-aeration tank 5. 56 are arranged in this order. Therefore, after the re-aeration tank 5, the micro-nano bubbles are further generated by the second micro-nano bubble generation tank 57, and the liquid containing the nano-nano bubbles is introduced into the rapid filter 55 by the pump 58, thereby treating the treated water from the re-aeration tank 5. The microorganisms are activated by the attachment of the introduced micro-nano bubbles, and the organic matter adhering to the rapid filter 55 and the organic matter adsorbing to the activated carbon of the activated carbon adsorption tower 56 are efficiently decomposed by the activated microorganisms. As a result, clogging of the rapid filter 55 can be prevented. Furthermore, the activated carbon of the activated carbon adsorption tower 56 can be regenerated, and the number of regenerations per year can be reduced.

  That is, according to the present embodiment, it becomes possible to perform further advanced treatment of the water to be treated, and it is more convenient to use nitrogen in a place where the discharge conditions of the treated water are considerably severe or to reuse the treated water. A waste water treatment apparatus can be provided. Furthermore, it is possible to provide a “nitrogen-containing wastewater treatment apparatus” which is an advanced treatment system but has a low initial cost as compared with the case of the fifth embodiment shown in FIG.

-7th Embodiment FIG. 7: is a figure which shows the structure in the nitrogen containing waste water treatment equipment of this Embodiment. The nitrogen-containing wastewater treatment apparatus shown in FIG. 7 is different from the nitrogen-containing wastewater treatment apparatus of the sixth embodiment shown in FIG. 6 in that the nitrogen-containing wastewater that flows into the first nitrification tank 6 is a surfactant-containing nitrogen wastewater. Is different in that. In addition, since the other structure is the same as the nitrogen-containing waste water treatment apparatus of the said 6th Embodiment shown in FIG. 6, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  In this nitrogen-containing wastewater treatment apparatus, the inflow water to the first nitrification tank 6 is a surfactant-containing nitrogen wastewater. Therefore, in some cases, the microbial degradability of the surfactant is poor and microbial treatment may be relatively difficult. However, on the other hand, if a surfactant is present in the water to be treated, micro / nano bubbles are generated remarkably smoothly. And in this Embodiment, since the micro nano bubble generation tank is arrange | positioned not only in the front | former stage of the 1st nitrification tank 6 but in the back | latter stage of the re-aeration tank 5, generation | occurrence | production of the micro nano bubble in the back | latter stage of the re-aeration tank 5 Is promoted. Therefore, the microorganisms are more activated, and not only the nitrogen in the water to be treated but also the surfactant can be decomposed.

  That is, according to the present embodiment, the reliability of the nitrogen-containing wastewater treatment apparatus is increased by arranging the second micro / nano bubble generation tank 57 at the rear stage of the re-aeration tank 5 and performing the two-stage treatment with the micro / nano bubbles. It can be done.

  The above-mentioned “micronano bubbles are remarkably smoothly generated when a surfactant is present in the water to be treated” means that the micronano bubbles in the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG. It can also be applied to the generation tank 1. Therefore, even when the surfactant-containing nitrogen wastewater is introduced into the nitrogen-containing wastewater treatment apparatus of the first embodiment shown in FIG. 1, a large amount of micro-nano bubbles are generated to further activate the microorganisms, The surfactant can be decomposed by the microorganisms activated from the above.

Eighth Embodiment FIG. 8 is a diagram showing a configuration in the nitrogen-containing wastewater treatment apparatus of the present embodiment. The nitrogen-containing wastewater treatment apparatus shown in FIG. 8 is different from the nitrogen-containing wastewater treatment apparatus of the seventh embodiment shown in FIG. 7 between the pump 58 and the rapid filter 55 and between the contact oxidation tank 53, the precipitation tank 54, and The third micro / nano bubble generation tank 59 is different in that it is arranged in this order. Other configurations are the same as those in the case of the nitrogen-containing wastewater treatment apparatus of the seventh embodiment shown in FIG. 7, and therefore, the same reference numerals are given and detailed descriptions thereof are omitted. Further, the contact oxidation tank 53 and the precipitation tank 54 are also the same as those in the fifth embodiment shown in FIG.

  In this nitrogen-containing wastewater treatment apparatus, the inflow water to the first nitrification tank 6 is a surfactant-containing nitrogen wastewater. Therefore, in some cases, the microbial degradability of the surfactant is poor and microbial treatment may be relatively difficult. In particular, nitrogen wastewater containing an organic fluorine-based surfactant such as perfluorooctane sulfonic acid or perfluorooctanoic acid is difficult to be treated with microorganisms even if two-stage treatment with micro-nano bubbles is performed.

  Therefore, in the present embodiment, a third micro / nano bubble generation tank 59 is disposed between the settling tank 54 and the rapid filter 55. Therefore, in this nitrogen-containing wastewater treatment apparatus, microbial decomposition can be performed on nitrogen wastewater containing an organic fluorosurfactant by performing three-stage treatment with micro-nano bubbles. The reliability of the apparatus can be further increased.

・ Experimental Example Based on FIG. 1, the capacity of the micro / nano bubble generation tank 1 is 0.2 m ³ , the capacity of the micro / nano bubble adhering tank 2 is 0.1 m ³ , the capacity of the nitrification tank 3 is 4 m ³ , and the capacity of the denitrification tank 4 is 3m ^3, the capacity of the re-aeration tank 5 was fabricated experimental device is 2m ^3. Then, when nitrogen-containing wastewater is introduced into the nitrification tank 3 and the denitrification tank 4 filled with the polyvinylidene chloride filler 13 and a trial operation is performed for about three months, a stable treated water quality is secured from the re-aeration tank 5. I was able to.

  Moreover, when the nitrogen removal rate was determined by analyzing the total nitrogen of the influent water and the treated water, the nitrogen removal rate was 90% or more, there was no foaming from the nitrification tank 3 and the re-aeration tank 5, The transparency of the treated water was 30 cm or more.

It is a figure which shows the structure in the nitrogen-containing waste water treatment apparatus of this invention. It is a figure which shows the structure in the nitrogen-containing waste water treatment apparatus different from FIG. It is a figure which shows the structure in the nitrogen-containing waste water treatment equipment different from FIG. 1 and FIG. It is a figure which shows the structure in the nitrogen-containing waste water treatment apparatus different from FIGS. It is a figure which shows the structure in the nitrogen-containing waste water treatment apparatus different from FIGS. It is a figure which shows the structure in the nitrogen-containing waste water treatment apparatus different from FIGS. It is a figure which shows the structure in the nitrogen-containing waste water treatment apparatus different from FIGS. It is a figure which shows the structure in the nitrogen-containing waste water treatment apparatus different from FIGS.

1 ... Micro / nano bubble generation tank,
2 ... Micro-nano bubble adhesion tank (to sludge)
3 ... Nitrification tank,
4 ... denitrification tank,
5 ... Re-aeration tank,
6 ... 1st nitrification tank,
7 ... Second nitrification tank,
8 ... 1st denitrification tank,
9 ... Second denitrification tank,
10 ... Turbidimeter,
11 ... 1st oxidation-reduction potentiometer,
12 ... Second oxidation-reduction potentiometer,
13 ... polyvinylidene chloride filling,
14 ... lower introduction pipe,
15 ... the hole of the lower introduction pipe,
16, 28 ... line mixer type air diffuser,
18, 27, 38 ... Blower,
19 ... first redox potential controller,
20: Second redox potential controller,
21 ... Sludge pump,
22 ... 1st submerged membrane pump,
23 ... Hydrogen donor tank,
24 ... hydrogen donor tank metering pump,
25. Second submerged membrane pump,
26 ... Submerged membrane,
32 ... Submersible pump type micro / nano bubble generator,
33 ... Swirl type micro / nano bubble generator,
36,52 ... Inflow pipe,
40 ... Turbidity controller,
42 ... Micro-nano bubble generation aid tank metering pump,
43 ... Micro-nano bubble generation aid tank,
44 ... circulation pump,
45 ... Air inlet pipe,
46 ... Needle valve,
47. Outflow pipe,
51 ... Diffuser,
53. Contact oxidation tank,
54 ... Precipitation tank
55 ... Rapid filter,
56 ... Activated carbon adsorption tower,
57. Second micro / nano bubble generating tank,
58 ... pump,
59 ... Third micro / nano bubble generating tank.

Claims (16)

A micro / nano bubble generator having a micro / nano bubble generator and generating micro / nano bubbles in the introduced water;
A micro / nano bubble adhering tank for adhering micro / nano bubbles in water containing micro / nano bubbles introduced from the micro / nano bubble generating tank to microorganisms in the introduced microorganism sludge;
It has a water depth of 7 m or more and is filled with a filler for adhering micro-nano bubbles, and microbial sludge from the micro-nano bubble adhering tank and nitrogen-containing waste water from the outside are introduced into the introduced nitrogen-containing waste water. A nitrification tank for nitrification treatment,
While being installed in the nitrification tank and having an inlet for introducing the microbial sludge and the nitrogen-containing wastewater at the upper end, the microorganism sludge and the nitrogen-containing wastewater introduced from the inlet at the bottom A nitrification tank lower introduction pipe having a discharge hole for discharging to the lowermost part of the nitrification tank ;
It has a water depth of 7 m or more, is filled with a filler for attaching micro-nano bubbles, water to be treated that has been subjected to nitrification by the nitrification tank is introduced, a hydrogen donor is added, and the introduced coverage is introduced. A denitrification tank that denitrifies the treated water;
The denitrification tank is installed in the denitrification tank and has an inlet at the upper end through which the water to be treated from the nitrification tank is introduced. A denitrification tank lower introduction pipe having a discharge hole for discharging at the lower part;
A re-aeration tank that has an aeration apparatus and that microbially decomposes the hydrogen donor in the water to be treated that has been introduced in the denitrification tank and into which the water to be treated has been excessively added in the denitrification tank. And a nitrogen-containing wastewater treatment apparatus. In the nitrogen-containing waste water treatment apparatus according to claim 1,
The nitrogen-containing wastewater treatment apparatus, wherein the microbial sludge introduced into the micro / nano bubble adhesion tank is introduced from the re-aeration tank. In the nitrogen-containing waste water treatment apparatus according to claim 2,
The nitrogen-containing wastewater treatment apparatus, wherein the micro / nano bubble generation tank has two types of micro / nano bubble generators, a submersible pump type micro / nano bubble generator and a swirl type micro / nano bubble generator. In the nitrogen-containing waste water treatment apparatus according to claim 1,
A nitrogen-containing wastewater treatment apparatus comprising a micro / nano bubble generation aid addition device for adding a micro / nano bubble generation aid to the micro / nano bubble generation tank. In the nitrogen-containing waste water treatment apparatus according to claim 4,
The above micro / nano bubble generation auxiliary agent adding device is:
A micro / nano bubble generation aid tank for storing the micro / nano bubble generation aid;
A nitrogen-containing wastewater treatment apparatus, comprising: a micro / nano bubble generation aid tank metering pump that transports the micro / nano bubble generation aid in the micro / nano bubble generation aid tank to the micro / nano bubble generation tank in a fixed amount. In the nitrogen-containing waste water treatment apparatus according to claim 5,
A turbidimeter installed in the micro / nano bubble generation tank and measuring the turbidity of the water to be treated in the micro / nano bubble generation tank,
Based on the measurement result by the turbidimeter, the transport amount of the micro / nano bubble generation aid by the micro / nano bubble generation aid tank metering pump is controlled so that the measurement result by the turbidimeter has a predetermined turbidity. A nitrogen-containing wastewater treatment apparatus comprising a turbidity controller. In the nitrogen-containing waste water treatment apparatus according to claim 1,
A nitrogen-containing wastewater treatment apparatus, wherein a contact oxidation tank, a precipitation tank, a rapid filter and an activated carbon adsorption tower are installed after the re-aeration tank. In the nitrogen-containing waste water treatment apparatus according to claim 1,
A nitrogen-containing wastewater treatment apparatus, wherein a second micro / nano bubble generation tank, a rapid filter, and an activated carbon adsorption tower are installed after the re-aeration tank. In the nitrogen-containing waste water treatment apparatus according to claim 1,
A nitrogen-containing wastewater treatment apparatus, wherein the nitrogen-containing wastewater introduced into the nitrification tank is a surfactant-containing nitrogen wastewater. In the nitrogen-containing waste water treatment apparatus according to claim 1,
The second micro / nano bubble generation tank, the precipitation tank, the third micro / nano bubble generation tank, the rapid filter and the activated carbon adsorption tower are installed after the re-aeration tank.
A nitrogen-containing wastewater treatment apparatus, wherein the nitrogen-containing wastewater introduced into the nitrification tank is a surfactant-containing nitrogen wastewater. In the nitrogen-containing waste water treatment apparatus according to claim 1,
A nitrogen-containing wastewater treatment apparatus, wherein a line mixer type air diffuser is installed in the micro / nano bubble adhesion tank, the nitrification tank, and the re-aeration tank. In the nitrogen-containing waste water treatment apparatus according to claim 1,
The denitrification tank lower introduction pipe is composed of a first denitrification tank lower introduction pipe, a second denitrification tank lower introduction pipe, and two denitrification tank lower introduction pipes,
The denitrification tank has a first denitrification tank in which the first denitrification tank lower introduction pipe is installed , the introduction port communicating with the upper part of the nitrification tank, and the introduction port communicated with the upper part of the first denitrification tank. The second denitrification tank lower introduction pipe is composed of two denitrification tanks and the second denitrification tank,
The nitrification tank is equipped with a line mixer type air diffuser,
The re-aeration tank includes a first pump for transferring microbial sludge in the re-aeration tank to the micro-nano bubble adhesion tank, and a second pump for transferring treated water in the re-aeration tank to the micro-nano bubble generation tank. Is installed,
A first oxidation-reduction potentiometer installed in the first denitrification tank and measuring the oxidation-reduction potential in the first denitrification tank;
Based on the measurement result of the first oxidation-reduction potentiometer, a first oxidation-reduction potential controller that controls the pumping amount of the blower that pumps air to the line mixer type diffuser of the nitrification tank;
A second oxidation-reduction potentiometer installed in the second denitrification tank and measuring the oxidation-reduction potential in the second denitrification tank;
Nitrogen comprising: a second oxidation-reduction potential controller for controlling a transfer amount of the first pump and the second pump of the re-aeration tank based on a measurement result of the second oxidation-reduction potentiometer Contains wastewater treatment equipment. In the nitrogen-containing waste water treatment apparatus according to claim 9 or 10,
The nitrogen-containing wastewater treatment apparatus, wherein the surfactant in the surfactant-containing nitrogen wastewater is an organic fluorine-based compound. In the nitrogen-containing waste water treatment apparatus according to claim 13,
The nitrogen-containing wastewater treatment apparatus, wherein the organic fluorine-based compound is perfluorooctanesulfonic acid or perfluorooctanoic acid. The micro / nano bubble generated in the micro / nano bubble generation tank having the micro / nano bubble generator is attached to the microorganisms in the introduced microbial sludge in the micro / nano bubble adhesion tank,
The microbial sludge containing the micro-nano bubbles attached to the microorganisms and the nitrogen-containing wastewater from the outside are introduced into the lowermost part of the nitrification tank having a depth of 7 m or more and filled with a filler for attaching micro-nano bubbles. Then, nitrification treatment is performed on the introduced nitrogen-containing wastewater,
Water to be treated that has been nitrified by the nitrification tank has a water depth of 7 m or more, and is introduced into the lowermost part of the denitrification tank filled with the filler for attaching micro-nano bubbles, and a hydrogen donor is added, Perform denitrification treatment on the treated water introduced above,
The water to be treated, which has been denitrified by the denitrification tank, is introduced into a re-aeration tank having an aeration device, and the hydrogen donor in the water to be treated added excessively in the denitrification tank is microbially decomposed. A nitrogen-containing wastewater treatment method characterized by that. The nitrogen-containing wastewater treatment method according to claim 15,
The nitrification tank is composed of two tanks, a first nitrification tank having a water depth of 7 m or more and a second nitrification tank having a water depth of 7 m or more,
The denitrification tank is composed of two tanks, a first denitrification tank having a water depth of 7 m or more and a second denitrification tank having a water depth of 7 m or more,
The first nitrification tank, the second nitrification tank, the first denitrification tank, and the second denitrification tank are provided with a lower introduction pipe having an inlet at the upper part and a discharge hole at the lower part,
The first nitrification tank and the second nitrification tank, the second nitrification tank and the first denitrification tank, and the first denitrification tank and the second denitrification tank are connected to each other in series by the lower introduction pipe. And
The microbial sludge introduced into the first nitrification tank and the nitrogen-containing waste water, the second nitrification tank, the first denitrification tank, and the water to be treated from the preceding tank introduced into the second denitrification tank, Nitrogen-containing, characterized in that it is introduced from the introduction port of the lower introduction pipe and flows down in the lower introduction pipe, and is introduced into the lowermost part of the nitrification tank and the denitrification tank from the discharge hole of the lower introduction pipe Wastewater treatment method.

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