JP2016174993A - Apparatus and method for treating water to be treated - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus or the like for treating water to be treated which can treat both first water to be treated containing ammonia and second water to be treated containing TMAH, and whose installation area can be made smaller, and whose operation management can be facilitated.SOLUTION: The apparatus 1 for treating water to be treated is provided for treating cleaning waste water W1 containing ammonia and development waste water W2 containing tetramethylammonium hydroxide (TMAH). The apparatus 1 comprises: a nitrifying unit 200 which oxidizes ammonia contained in the cleaning waste water W1 into nitrite nitrogen and nitrate nitrogen using nitrifying bacteria containing ammonia oxidation bacteria; and a denitrifying unit 500 which denitrifies nitrite nitrogen and nitrate nitrogen contained in cleaning waste water W1' which is treated by the nitrifying unit 200, using TMAH contained in the development waste water W2 as a hydrogen donor.SELECTED DRAWING: Figure 1

Description

More specifically, the present invention relates to a first treated water containing ammonia and tetramethylammonium hydroxide (TMAH: [(CH ₃ ) ₄ N] ⁺ [OH] ⁻ ). The present invention relates to a treatment apparatus and the like for treating treated water together.

  For example, when a semiconductor or a liquid crystal is manufactured, a cleaning process may be included in the manufacturing process. The cleaning waste water discharged from this cleaning process contains ammonia. Similarly, a development process may be included in the manufacturing process. TMAH is contained in the development waste water discharged from this development process.

Patent Document 1 discloses a method for treating ammonia-containing wastewater, in which ammonia gas is diffused from the wastewater by blowing air and steam into the wastewater containing ammonia, and then the ammonia gas is oxidized and decomposed by a catalyst. As the air blown into the waste water, there is disclosed one that uses air heated and exchanged with a processing gas after the oxidative decomposition of ammonia gas.
Further, in Patent Document 2, when ammonia-containing nitrogen-containing wastewater is subjected to catalytic wet oxidation, gas-liquid mixed fluid discharged from the catalytic wet oxidation apparatus is gas-liquid separated, and then the oxygen concentration in the gas phase is measured and measured. And controlling the amount of oxygen-containing gas flowing into the apparatus so that the set oxygen concentration value falls within a preset oxygen concentration range or a set concentration value. Is disclosed.
Furthermore, in Patent Document 3, in the treatment of quaternary ammonium salt-containing wastewater by microorganisms, mineral acid and nitric acid serving as a nitrogen nutrient source are used as neutralizing agents for neutralization of alkaline quaternary ammonium salt-containing wastewater. A method is disclosed in which the mixed liquid is passed through a filler layer on which microorganisms are propagated to repeatedly remove the same amount of treated water as the injected waste liquid without changing the pH in the reaction tank. Yes.
Further, Patent Document 4 discloses an anaerobic biological treatment method for anaerobically biologically treating wastewater containing an alkylammonium salt and wastewater containing an organic substance having 6 or less carbon atoms. It is disclosed to supply molasses after raising.
Further, Patent Document 5 discloses a reaction tank that is an example of a reaction means that stores wastewater and oxidizes ammonia in the wastewater, and a drainage supply pipe that is an example of a wastewater supply means that batch-feeds wastewater to the reaction tank. , A supernatant liquid discharge pipe as an example of a liquid discharge means for discharging the supernatant liquid of the wastewater stored in the reaction tank, and an air supply device as an example of an oxygen supply means for supplying air (atmosphere) from the outside of the tank As an example of the detection means, there is disclosed a wastewater treatment device including a pH detection sensor, a dissolved oxygen detection sensor, an ammonia concentration detection sensor, and a control device that performs batch supply control of wastewater.

Japanese Patent Laid-Open No. 8-197039 JP-A-7-265878 JP-A-8-80494 JP 2010-274207 A JP 2012-245479 A

Conventionally, washing waste water and development waste water are generally treated separately.
For example, there is a method of treating ammonia contained in washing wastewater by a biological nitrification / denitrification method or a physical treatment method.

Among them, the biological nitrification / denitrification method has a high concentration of ammonia contained in the washing waste water, and nitrification is relatively difficult. In addition, since organic substances usually used as hydrogen donors required for denitrification are not so much contained in the washing waste water, it is necessary to add organic substances such as methanol. Therefore, in the past, it was not so often adopted.
As the physical treatment method, a method using a combination of an ammonia stripping method and a catalytic combustion method or a wet oxidation method using a catalyst is used. However, these methods require strict operating condition management and a complicated control system in order to suppress NOx emission.

  On the other hand, there are a method of biologically processing TMAH contained in the development waste water, or a method of industrial waste processing by reducing the amount by evaporation concentration.

Of these, biological treatment methods are often unstable because TMAH is a hardly degradable and toxic substance. Therefore, in the past, it was not so often adopted.
Moreover, the method of reducing the amount by evaporative concentration and performing the industrial waste treatment has a problem that the energy cost required for evaporative concentration tends to increase.

  In either case, if the cleaning wastewater and the development wastewater are processed separately, separate processing devices are required. Therefore, the installation space for the processing apparatus tends to increase. Also, the operation management of the processing device tends to be complicated.

  Therefore, the present invention can treat both the first treated water such as cleaning waste water containing ammonia and the second treated water such as developing waste water containing TMAH, and the installation area can be easily reduced. An object of the present invention is to provide an apparatus for treating water to be treated that is easy to manage.

  Thus, according to the present invention, there is provided an apparatus for treating water to be treated for treating a first treated water containing ammonia and a second treated water containing tetramethylammonium hydroxide. Nitrification means for oxidizing ammonia contained in water to nitrite nitrogen and nitrate nitrogen using nitrifying bacteria including ammonia oxidizing bacteria, and nitrite-like properties contained in the first treated water treated by the nitrification means A denitrification means for denitrifying nitrogen and nitrate nitrogen using tetramethylammonium hydroxide contained in the second treated water as a hydrogen donor. Is done.

Here, the denitrification means preferably performs denitrification using facultative anaerobic heterotrophic bacteria, and the facultative anaerobic heterotrophic bacteria preferably belong to the family Xanthomonas.
Moreover, the 1st to-be-processed water can be the washing | cleaning waste_water | drain discharged | emitted from a washing | cleaning process, and the 2nd to-be-processed water can be made into the development waste_water | drain discharged | emitted from a image development process.
Furthermore, it is preferable to further comprise a control means for maintaining the concentration of ammonia contained in the first treated water in a predetermined range by the nitrification means.
Furthermore, the ammonia-oxidizing bacteria are preferably a plurality of types of ammonia-oxidizing bacteria, which are beta-proteobacteria, and more preferably include those belonging to each of the genera Nitrosomonas and Nitrosospira.
The control means preferably maintains the ammonia concentration in a region where the growth rate of the ammonia-oxidizing bacteria belonging to the halophilic and salt-tolerant nitrosomonas genus is larger than the growth rate of the ammonia-oxidizing bacteria belonging to the nitrosospira genus. .

  Moreover, according to this invention, it is the processing method of the to-be-processed water which processes the 1st to-be-processed water containing ammonia, and the 2nd to-be-processed water containing tetramethylammonium hydroxide, Comprising: A nitrification step of oxidizing the contained ammonia into nitrite nitrogen and nitrate nitrogen using nitrifying bacteria including ammonia oxidizing bacteria, nitrite nitrogen contained in the first treated water treated by the nitrification step, and And a denitrification step of denitrification using tetramethylammonium hydroxide contained in the second treated water as a hydrogen donor, and a method for treating the treated water. .

  According to the present invention, the first treated water containing ammonia and the second treated water containing TMAH can be treated together, and the installation area can be easily reduced and the operation management can be easily performed. A treatment apparatus or the like for treated water can be provided.

It is the figure explaining the whole structure of the processing apparatus of the to-be-processed water of this Embodiment. (A)-(b) is the figure explaining the change of the ammonia concentration in a reaction tank by the case where wash wastewater is supplied batchwise to the reaction tank, and the case where it supplies continuously. Nitrosomonas europaea belonging to the genus Nitrosomonas and nitrosospira sp. It is the figure which showed the relationship of the growth rate with respect to ammonia concentration by AV (Nitrosospira sp. AV). It is the figure which showed the composition of the washing waste_water | drain. It is the figure which showed the driving | running condition of the nitrification unit. Is a diagram showing changes of the concentration of ammonium sulfate _{((NH 4) 2 SO 4} ). It is the figure which showed the water quality change of the washing waste_water | drain in the reaction tank of a nitrification unit. It is the figure which showed the nitrate nitrogen accumulation rate in the ratio of the density | concentration of nitrate nitrogen, and the density | concentration of nitrite nitrogen. It is the figure explaining the microflora which inhabits in the reaction tank of a nitrification unit. It is the figure which showed the water quality change of the liquid mixture. It is the figure which showed the phylogenetic tree of the bacteria which inhabit in a reaction tank.

Hereinafter, embodiments for carrying out the present invention will be described in detail. The present invention is not limited to the following embodiments, and various modifications can be made within the scope of the invention. The drawings used are for explaining the present embodiment and do not represent the actual size.
Hereinafter, a treatment apparatus for treated water to which the present embodiment is applied will be described with reference to the drawings.

<Description of the whole treatment apparatus for treated water>
FIG. 1 is a diagram illustrating an overall configuration of a water treatment apparatus according to the present embodiment.
The treated water treatment apparatus 1 shown in the figure is arranged in the first drain tank 100 that stores the cleaning waste water W1 that is the first treated water, and the rear stage of the first drain tank 100, and is an example of a nitrification unit. A certain nitrification unit 200, an intermediate tank 300 for storing cleaning wastewater W1 ′ processed by the nitrification unit 200, a second drainage tank 400 for storing development wastewater W2, which is the second treated water, A denitrification unit 500 that is an example of a denitrification unit, a first neutralization liquid tank 600 that stores an alkaline neutralization liquid, and an acidic neutralization liquid are disposed downstream of the drainage tank 400 and the intermediate tank 300. The second neutralization liquid tank 650 to be stored, the re-aeration tank 700 disposed downstream of the denitrification unit 500, the sedimentation tank 800 for separating sludge and fungus bodies, and the overall operation of the processing apparatus 1 are controlled. And a control unit 900 which is an example of a control means.

  In the treatment apparatus 1 of the present embodiment, the cleaning wastewater W1 that is the first treated water is first stored in the first drainage tank 100. Next, the cleaning waste water W1 is sent to the nitrification unit 200 through the pipe H1 by driving the pump P1, and the nitrification unit 200 performs nitrification treatment. Further, the cleaning waste water W1 'subjected to nitrification is temporarily stored in the intermediate tank 300 through the pipe H2 by driving the pump P2. The washing waste water W1 'is sent from the intermediate tank 300 to the denitrification unit 500 through the pipe H3 by driving the pump P6 as necessary.

  On the other hand, the development waste water W2 that is the second treated water is first stored in the second drain tank 400. Next, the development waste water W2 is sent to the denitrification unit 500 through the pipe H4 by driving the pump P7. The development waste water W2 is mixed with the cleaning waste water W1 'after the nitrification process is performed in the denitrification unit 500, and the denitrification process is performed. Further, if necessary, an alkaline neutralizing solution is supplied from the first neutralizing solution tank 600 to the nitrification unit 200 through the pipe H5 by driving the pump P4. If necessary, an acidic neutralizing solution is supplied from the second neutralizing solution tank 650 to the second drainage tank 400 through the pipe H6 by driving the pump P5.

Further, the water after the denitrification process is performed is sent to the re-aeration tank 700 through the pipe H7 by driving the pump P8, and aeration is performed in the re-aeration tank 700. Finally, the treated water is sent to the sedimentation tank 800 through the pipe H8 by driving the pump P10.
The driving of each pump is controlled by the control unit 900.

<Description of configuration of each part of processing apparatus>
Next, the configuration of each part of the processing apparatus 1 will be described in detail.
The nitrification unit 200 oxidizes ammonia contained in the washing waste water W1 to nitrite nitrogen and nitrate nitrogen using nitrification bacteria including ammonia oxidation bacteria. However, as described below, in this embodiment, the ammonia-oxidizing bacteria oxidize ammonia mainly to nitrite nitrogen.

  The cleaning wastewater W1 is also referred to as SC-1 wastewater, and contains a high concentration of ammonia used in the cleaning process when manufacturing semiconductors and liquid crystals. In the present embodiment, activated sludge K1 is introduced into a reaction tank 210 described later, and an environment in which ammonia-oxidizing bacteria predominate in the activated sludge K1 is set. As a result, ammonia is oxidized to nitrite nitrogen and nitrate nitrogen.

Here, when oxidizing ammonia by biological treatment, ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) are known as bacteria that oxidize ammonia. Ammonia-oxidizing bacteria and nitrite-oxidizing bacteria are autotrophic bacteria that do not use organic matter for cell synthesis but synthesize cells by immobilizing inorganic substances.
Ammonia oxidizing bacteria oxidize ammonia to nitrite nitrogen. Nitrite oxidizing bacteria also oxidize ammonia to nitrate nitrogen. However, nitrite-oxidizing bacteria need more oxygen to oxidize ammonia to nitrate nitrogen than ammonia-oxidizing bacteria oxidize ammonia to nitrite nitrogen. This oxygen is supplied by sending air (air) into the cleaning waste water W1, but there is a problem that the operating cost of a pump, a blower or the like for sending air becomes higher.
Therefore, it is preferable that the reaction tank 210 has an environment in which ammonia-oxidizing bacteria predominate over nitrite-oxidizing bacteria, thereby predominating the reaction of oxidizing ammonia to nitrite nitrogen.

  There are a plurality of ammonia-oxidizing bacteria, and their growth rates are different from each other. Therefore, an environment in which ammonia-oxidizing bacteria having a faster growth rate dominate can be obtained, whereby the rate at which ammonia-oxidizing bacteria oxidize ammonia to nitrite nitrogen can be improved.

  Therefore, in the present embodiment, this is realized by configuring the nitrification unit 200 as follows.

  The nitrification unit 200 includes a reaction tank 210 that performs nitrification, an air supply device 220 that supplies air to the reaction tank 210 and performs aeration, a dissolved oxygen detection sensor 230 that detects dissolved oxygen in the cleaning waste water W1, and a cleaning. A pH detection sensor 240 for detecting the pH of the waste water W1 and an ammonia concentration detection sensor 250 for detecting the ammonia concentration in the cleaning waste water W1 are provided.

  In the reaction tank 210, activated sludge K1 is stored together with the washing waste water W1. As will be described in detail later, ammonia-oxidizing bacteria are present in the activated sludge K1, and the oxidizing bacteria are nitrified by biological treatment with the ammonia-oxidizing bacteria.

  The air supply unit 220 includes a supply pipe 221 that is a pipe that supplies air, and a diffuser plate 222 that is attached to one end of the supply pipe 221 and diffuses air into the cleaning waste water W1. The supply pipe 221 is provided with an air supply pump P3 so that air is sent out. A large number of holes are formed in the air diffuser plate 222, and air is sent into the cleaning waste water W1 through the holes as fine bubbles. Further, the diffuser plate 222 is disposed in the lower part of the reaction tank 210, and air can be sent into the reaction tank 210 from the lower part of the reaction tank 210. The air sent from the lower part of the reaction tank 210 rises in the cleaning wastewater W1 due to its buoyancy, and diffuses widely in the activated sludge K1 floating in the cleaning wastewater W1. As a result, ammonia oxidizing bacteria can be suspended in the entire cleaning waste water W1, and oxygen can be sufficiently supplied to the ammonia oxidizing bacteria. As a result, the oxidation reaction of ammonia can proceed efficiently.

The dissolved oxygen (DO) concentration in the cleaning waste water W1 is detected by the dissolved oxygen detection sensor 230. As the dissolved oxygen detection sensor 230, an existing device that measures the concentration of dissolved oxygen in the cleaning waste water W1 using a dissolved oxygen electrode can be used.
In the present embodiment, the amount of dissolved oxygen is monitored by the dissolved oxygen detection sensor 230 during the nitrification treatment. Based on the detected dissolved oxygen amount, the control unit 900 controls the air supply pump P3 to adjust the air supply amount and adjust the dissolved oxygen amount in the cleaning waste water W1.

  Ammonia-oxidizing bacteria and nitrite-oxidizing bacteria have different affinity for oxygen, and ammonia-oxidizing bacteria are more dominant than nitrite-oxidizing bacteria in a region where dissolved oxygen is at a relatively low concentration. Therefore, by adjusting the amount of dissolved oxygen in the washing waste water W1, it is possible to create an environment in which ammonia-oxidizing bacteria are likely to be dominant.

The pH of the cleaning waste water W1 is detected by the pH detection sensor 240. As the pH detection sensor 240, an existing device that measures the hydrogen ion concentration in the cleaning waste water W1 with a pH electrode can be used.
In the present embodiment, the pH is monitored by the pH detection sensor 240 during the nitrification treatment. When the detected pH falls below a predetermined value (for example, pH = 7.0), an alkaline neutralizing solution stored in the first neutralizing solution tank 600 is added. That is, the control unit 900 drives the pump P4 to introduce the neutralizing liquid into the nitrification unit 200 and raise the pH of the cleaning waste water W1. As the alkaline neutralizing solution, for example, sodium hydrogen carbonate (NaHCO ₃ ), sodium hydroxide (NaOH), or potassium hydroxide (KOH) can be used.

  In regions where the pH is relatively high, ammonia-oxidizing bacteria are more dominant than nitrite-oxidizing bacteria. Therefore, by adjusting the pH in the washing waste water W1, it is possible to create an environment in which ammonia-oxidizing bacteria are likely to dominate.

Further, the ammonia concentration of the cleaning waste water W1 is detected by the ammonia concentration detection sensor 250. As the ammonia concentration detection sensor 250, an existing device that measures the concentration of ammonium ions (NH ₄ ⁺ ) in the cleaning waste water W1 with an ammonia electrode can be used.

  In the present embodiment, the ammonia concentration in the reaction tank 210 is maintained by batch supply (intermittent supply) without continuously supplying the cleaning wastewater W1 to the reaction tank 210. Here, the continuous supply is a supply method in which the cleaning waste water W1 is continuously discharged from the reaction tank 210 while the cleaning waste water W1 is continuously supplied to the reaction tank 210. On the other hand, the batch supply means that the cleaning waste water W1 in the reaction tank 210 is nitrified for a predetermined time, and then a part of the cleaning waste water W1 is discharged, and the discharged cleaning waste water W1 is newly supplied. It is a repeated supply method.

FIGS. 2A to 2B are diagrams illustrating changes in the ammonia concentration in the reaction tank 210 when the cleaning wastewater W1 is supplied to the reaction tank 210 in batches and when it is continuously supplied.
Among these, Fig.2 (a) has shown transition of the ammonia concentration when wash wastewater W1 is supplied to the reaction tank 210 batch. FIG. 2B shows the transition of the ammonia concentration when the cleaning waste water W1 is continuously supplied to the reaction tank 210. 2A to 2B, the horizontal axis represents time, and the vertical axis represents ammonia concentration (NH ₄ ⁺ concentration).

  As shown in FIG. 2A, when the cleaning waste water W1 is supplied batchwise to the reaction vessel 210, the ammonia concentration repeatedly increases and decreases with the passage of time. In this case, the ammonia concentration increases when the cleaning waste water W1 is supplied to the reaction tank 210. Further, the ammonia concentration decreases as time passes and nitrification progresses.

On the other hand, as shown in FIG. 2B, when the washing waste water W1 is continuously supplied to the reaction tank 210, the ammonia concentration becomes constant over time.
Comparing FIG. 2 (a) and FIG. 2 (b), overall, the ammonia concentration is higher when the washing waste water W1 is supplied batchwise to the reaction tank 210 than when it is supplied continuously to the reaction tank 210. There is a tendency.

  In general, with ammonia concentration bacteria, the growth rate of ammonia-oxidizing bacteria first increases linearly, and then the degree of increase gradually attenuates and converges to the maximum specific growth rate, which is the maximum value. The growth curve of the ammonia oxidation rate with respect to the ammonia concentration can be roughly divided into two types depending on the type. One of these is called r-strategist, which has a high growth rate at a high concentration of ammonia. On the other hand, the growth rate is not as high as r-strategist when ammonia is high concentration, but it is called K-strategist where growth rate exceeds r-strategist at low concentration. The growth curves of these two types of ammonia-oxidizing bacteria have an intersection at a certain ammonia concentration, and when the ammonia concentration in the reaction vessel 210 is lower than this intersection, more K-strategist ammonia-oxidizing bacteria grow and ammonia When the concentration is higher than this intersection, more r-strategist ammonia-oxidizing bacteria grow. That is, by adjusting the ammonia concentration in the reaction tank 210, it is possible to predominate either the K-strategist or the r-strategist ammonia-oxidizing bacteria in the reaction tank 210.

  Examples of ammonia oxidizing bacteria dominant in the washing waste water W1 containing ammonia at a high concentration include halophilic and salt-tolerant Nitrosomonas and Nitrosospira. Nitrosomonas is an r-strategist, and Nitrosospira is a K-strategist. These are beta proteobacteria.

FIG. 3 shows Nitrosomonas europaea belonging to the genus Nitrosomonas and nitrosospira sp. It is the figure which showed the relationship of the growth rate with respect to ammonia concentration by AV (Nitrosospira sp. AV). FIG. 3 shows both growth curves. Here, the horizontal axis represents ammonia concentration (NH ₄ ⁺ concentration), and the vertical axis represents growth rate (Specific growth rate).

  As shown in the figure, in a region where the ammonia concentration is relatively low, nitrosospira sp. The growth rate of AV is faster than that of Nitrosomonas europia belonging to the genus Nitrosomonas. However, as the ammonia concentration increases, this relationship is reversed, and the growth rate of the nitrosomonas europia genus Nitrosomonas is faster.

  When the dissolved oxygen concentration in the reaction vessel 210 is constant, for example, 1.5 mg / L, the intersection of both growth curves is 35 mg-N / L. Therefore, when the ammonia concentration is 35 mg-N / L or more, the nitrosomonas europia of the genus Nitrosomonas dominates, and when it is less than this concentration, the nitrosospira sp. AV becomes dominant. By adjusting the ammonia concentration in the reaction tank 210 in this way, it becomes possible to predominate ammonia oxidizing bacteria having different ammonia oxidizing performances.

  In the present embodiment, the cleaning wastewater W1 is supplied batchwise to the reaction tank 210, and the ammonia concentration in the cleaning wastewater W1 is set higher, so that the nitrosomonas europia genus is dominant. As shown in FIG. 3, the ammonia-oxidizing bacteria have a very high growth rate in a region where the ammonia concentration is high, so that more ammonia oxidizing bacteria are present in the washing waste water W1. As a result, the nitrification treatment can be performed more efficiently.

  In the present embodiment, the ammonia concentration is monitored by the ammonia concentration detection sensor 250 during the nitrification treatment. When the detected ammonia concentration falls below a predetermined value, the control unit 900 drives the pump P2 to discharge a part of the cleaning waste water W1. Further, the control unit 900 replenishes the cleaning waste water W1 that is discharged by driving the pump P1. The discharge of the cleaning waste water W1 is performed by once suspending the activated sludge K1 and then discharging the supernatant liquid of the cleaning waste water W1. In the present embodiment, the concentration of ammonia contained in the cleaning wastewater W1 is maintained in a predetermined range by supplying the cleaning wastewater W1 batchwise. The ammonia concentration is maintained in a region where the growth rate of the ammonia-oxidizing bacteria belonging to the genus Nitrosomonas is greater than the growth rate of the ammonia-oxidizing bacteria belonging to the genus Nitrosospira.

  The denitrification unit 500 uses nitrite nitrogen and nitrate nitrogen contained in the washing waste water W1 ′ treated by the nitrification unit 200 as tetrahydrogen ammonium hydroxide (TMAH) contained in the development waste water W2 as a hydrogen donor. Denitrify.

  The denitrification unit 500 is supplied with the development waste water W2 from the second drain tank 400 and the cleaning drain W1 'from the intermediate tank 300. However, the development waste water W2 is alkaline and is not suitable as it is for the denitrification unit 500 to perform the denitrification treatment. Therefore, an acidic neutralization liquid is added from the second neutralization liquid tank 650 to the second drainage tank 400, and neutralization is performed in advance in the second drainage tank 400.

  The denitrification unit 500 includes a reaction tank 510 and a stirring blade 520 for stirring the cleaning waste water W1 'and the development waste water W2 (hereinafter sometimes referred to as "mixed liquid W3") in the reaction tank 510.

  In the reaction tank 510, the activated sludge K2 is stored together with the mixed liquid W3. In the reaction tank 510, biological treatment is performed in the same manner as in the nitrification unit 200, thereby denitrifying nitrogenous nitrate and nitrate nitrogen. In the present embodiment, facultative anaerobic heterotrophic bacteria of the Xanthomonas family live in the activated sludge K2, and denitrification is performed by biological treatment.

At this time, when denitrifying nitrite nitrogen and nitrate nitrogen contained in the washing waste water W1 ′, tetramethylammonium hydroxide (TMAH) contained in the development waste water W2 becomes a hydrogen donor.
Specifically, this reaction becomes the following formulas (1) and (2). The expression (1) is a reaction for denitrifying nitrite nitrogen, and the expression (2) is a reaction for denitrifying nitrate nitrogen.

C ₄ H ₁₃ ON + 8NO ₂ ⁻ + 8H ⁺ = 4N ₂ + 3CO ₂ + NH ₄ ⁺ + HCO ₃ ⁻ + 8H ₂ O
... (1)
C ₄ H ₁₃ ON + 4.8NO ₃ ⁻ + 4.8H ⁺ = 2.4N ₂ + 3CO ₂ + NH ₄ ⁺ + HCO ₃ ⁻ + 6.4H ₂ O (2)

  Also in this embodiment, the mixed liquid W3 is supplied batchwise. That is, the liquid mixture W3 in the reaction vessel 510 is denitrified for a predetermined time, and then a part of the liquid mixture W3 is discharged, and the discharged waste water W1 ′ and developing waste water W2 are newly supplied. repeat. The mixed liquid W3 is discharged by precipitating the activated sludge K2 and then discharging the supernatant liquid of the mixed liquid W3.

  During the denitrification process, the inside of the reaction vessel 510 is stirred by the stirring blade 520. As a result, the mixed liquid W3 and the activated sludge K2 are agitated, and both come into contact with each other at a high frequency, whereby the denitrification treatment can be promoted.

The re-aeration tank 700 removes remaining organic substances by performing re-aeration on the mixed solution W <b> 4 discharged from the denitrification unit 500.
The re-aeration tank 700 includes an air supply unit 720. The air supply unit 720 includes a supply pipe 721 that is a pipe that supplies air, and a diffuser plate 722 that is attached to one end of the supply pipe 721 and diffuses air into the mixed solution W4. The supply pipe 721 is provided with an air supply pump P9, and thereby air is sent out. A large number of holes are formed in the diffuser plate 722, and air is sent into the mixed liquid W4 through the holes as fine bubbles.

  The sedimentation tank 800 stores the treated water W5 after the re-aeration is performed, and performs the standing. As a result, the sludge is precipitated and the sludge and the bacterial cells are separated.

  According to the processing apparatus 1 described in detail above, the cleaning waste water W1 containing ammonia and the developing waste water W2 containing TMAH can be treated together. Therefore, the installation area of the processing apparatus 1 tends to be small, and the operation management is also easy. In addition, TMAH is used as a hydrogen donor during the denitrification treatment. Thereby, it is not necessary to add an organic substance or the like separately, or the amount of addition can be reduced.

  Moreover, the processing method which the processing apparatus 1 explained in full detail performs the to-be-processed water which processes the waste_water | drain W1 which is the 1st to-be-processed water containing ammonia, and the developing waste water W2 which is the 2nd to-be-processed water containing TMAH. In the treatment method, ammonia contained in the cleaning wastewater W1 is oxidized to nitrite nitrogen and nitrate nitrogen using nitrifying bacteria including ammonia oxidizing bacteria, and the cleaning wastewater W1 treated by the nitrification step is used. A nitrite nitrogen and a nitrate nitrogen contained in the development waste water W2 as a hydrogen donor, and a denitrification step of denitrifying the nitrite nitrogen and nitrate nitrogen. it can.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, this invention is not limited by these Examples, unless the summary is exceeded.

The treatment waste water W1 and the development waste water W2 were treated using the treatment apparatus 1 shown in FIG.
First, the nitrification unit 200 tried to predominate ammonia oxidizing bacteria.

  A cleaning wastewater W1 having the composition shown in FIG. 4 was prepared and stored in the first drainage tank 100. Moreover, seed sludge was introduced into the reaction tank 210 as activated sludge K1 so as to have a volume of 8.4 L 2/3.

Next, (i) the pump P1 was driven to introduce the cleaning waste water W1 into the reaction vessel 210. The washing waste water W1 introduced at this time was set to have a volume of 1/3 of 8.4 L. At this time, the air supply pump P3 was driven, air was supplied from the air supply unit 220, and the cleaning waste water W1 was aerated.
Further, (ii) after the introduction of the cleaning waste water W1, air was continuously supplied from the air supply device 220, and the cleaning waste water W1 was aerated. The aeration time was 465 minutes in combination with (i). Then, the air supply pump P3 was stopped and activated sludge K1 was precipitated.
Next, (iii) the pump P2 was driven, and the supernatant liquid corresponding to 1/3 of 8.4 L was discharged to the intermediate tank 300.

  The above (i) to (iii) were taken as one cycle, and the time required for one cycle was set to 8 hours. FIG. 5 shows the detailed operating conditions for this one cycle. In this case, three cycles can be repeated per day. In this operating condition, the nitrification unit 200 was operated for 3 years.

Then, the nitritation ability and bacterial community structure inhabiting the reaction tank 210 were evaluated. The concentration of ammonia nitrogen shown in FIG. 4 was started from 100 mL as shown in FIG. 6, and the concentration was gradually increased when the removal of ammonia was stabilized.
In addition, since the introduction amount and discharge | emission amount of the washing | cleaning waste water W1 in 1 cycle are 1/3 of 8.4L, the 8.4L washing | cleaning waste water W1 can be processed in one day (3 cycles). The temperature of the washing waste water W1 in the reaction vessel 210 was 28 ° C.

FIG. 7 is a view showing a change in the water quality of the washing waste water W1 in the reaction tank 210. FIG.
Here, the horizontal axis represents the number of days (Time), and the vertical axis represents the concentration (N-concentration) of the component contained in the cleaning waste water W1. In this case, the components are nitrite nitrogen, nitrate nitrogen and ammonia.
FIG. 8 is a graph showing the nitrate nitrogen accumulation rate in terms of the ratio of nitrate nitrogen concentration and nitrite nitrogen concentration. Here, the horizontal axis represents the number of days (Time), and the vertical axis represents the ratio (Nitrite accumulatuion efficiency) of nitrite nitrogen in the components shown in FIG.

As shown in FIG. 7, in the initial stage (20 days), accumulation of both nitrite nitrogen and nitrate nitrogen is observed. However, it can be seen that nitrite nitrogen accumulates stably from day 100 onwards.
From this result, it can be seen that ammonia is stably nitrified and nitrite nitrogen accumulates under the operating conditions of FIG.

Next, the flora inhabiting the reaction vessel 210 was observed by applying a real-time quantitative PCR method. The result is shown in FIG.
FIG. 9 shows the respective abundances of ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB), Nitrobacter genus and Nitrospira (Nitrospira) genus, and whole bacteria. Here, the horizontal axis represents the number of days (Time), and the vertical axis represents the abundance (Abundance).
As can be seen, the amount of ammonia-oxidizing bacteria (AOB) significantly increases with time. In addition, the Nitrobacter genus, which is NOB, does not change much with the passage of days, whereas the Nitrospira genus fell below the lower limit of detection (0.1% or less) from the middle. It can be seen that the washout was performed by the operation of the nitrification unit 200.

  Further, the washing waste water W1 'discharged to the intermediate tank 300 in the above (iii) was introduced into the reaction tank 510 of the denitrification unit 500 by driving the pump P6. The concentration of nitrogen nitrite in the washing wastewater W1 'was 900 mg-N / L, and the concentration of nitrogen nitrate was 60 mg-N / L. The simulated development waste water W2 was stored in the second drain tank 400. Then, dilute hydrochloric acid (0.1 M) was introduced as an acidic neutralization solution from the second neutralization solution tank 650 to adjust the pH to 7.8. Then, the development waste water W2 after neutralization was introduced into the reaction vessel 510 by driving the pump P7. The mixed solution W3 of the cleaning wastewater W1 'and the developing wastewater W2 introduced into the reaction tank 510 was adjusted to have a TMAH concentration of 1000 mg-C / L.

  The mixed solution W3 was introduced into the reaction vessel 510 so as to have a volume of 2.5 L. Moreover, seed sludge was introduced into the reaction tank 510 as the activated sludge K2.

Next, (iv) 1.5 L of the mixed solution W3 was introduced into the reaction vessel 510.
Further, (v) the stirring blade 520 was rotated to perform denitrification treatment for 3 days. Thereafter, the stirring blade 520 was stopped and the activated sludge K2 was precipitated.
Next, (vi) the pump P7 was driven, and the supernatant corresponding to a volume of 1.5 L was discharged to the re-aeration tank 700.

The above (iv) to (vi) were taken as one cycle, and this was repeated for about 2 months. The temperature of the mixed solution W3 in the reaction vessel 510 was 28 ° C.
Then, the TMAH reduction amount and the NOx reduction amount in the mixed solution W3 in the reaction vessel 510 were evaluated.

FIG. 10 is a diagram showing a change in water quality of the mixed solution W3.
Here, the horizontal axis represents the number of days (Time), and the vertical axis represents the decrease amount of TMAH as the decrease amount of TOC (dTOC) and the decrease amount of NOx (dNOx).
As shown in the figure, both TOC and NOx decrease. This indicates that about 10% of organic matter has been treated by denitrification.

  Next, the flora inhabiting the reaction tank 510 was observed by applying the PCR-DGGE method. And the band containing the microbe which increased remarkably by the driving | operation of the denitrification unit 500 was cut out, the sequence analysis was performed after that, and the phylogenetic tree was created.

  The results are shown in FIG. Bacteria that increased most markedly in the illustrated phylogenetic tree are indicated by No1. The bacterium represented by No1 was a species close to Termomonas of Xanthomonadaceae (Xanthomonasaceae) having a denitrification function (98% homology). From this, it can be seen that denitrification treatment is possible using TMAH in the development waste water W2 as a hydrogen donor.

DESCRIPTION OF SYMBOLS 1 ... Processing apparatus, 200 ... Nitrification unit, 500 ... Denitrification unit, 900 ... Control unit, W1 ... Washing waste water, W2 ... Development waste water, W3, W4 ... Mixed liquid, W5 ... Treated water, K1, K2 ... Activated sludge

Claims (9)

A treatment apparatus for treating water for treating first treated water containing ammonia and second treated water containing tetramethylammonium hydroxide,
Nitrification means for oxidizing ammonia contained in the first treated water into nitrite nitrogen and nitrate nitrogen using nitrifying bacteria including ammonia oxidizing bacteria;
Nitrite nitrogen and nitrate nitrogen contained in the first treated water treated by the nitrification means are denitrified using tetramethylammonium hydroxide contained in the second treated water as a hydrogen donor. Denitrification means to perform,
An apparatus for treating water to be treated.   The apparatus for treating treated water according to claim 1, wherein the denitrification means performs denitrification using facultative anaerobic heterotrophic bacteria.   The treatment apparatus for water to be treated according to claim 2, wherein the facultative anaerobic heterotrophic bacteria belong to the family Xanthomonas.   The said 1st to-be-processed water is the washing | cleaning waste_water | drain discharged | emitted from a washing | cleaning process, and the said 2nd to-be-processed water is a development waste_water | drain discharged | emitted from a image development process. Treatment equipment for treated water.   The treatment apparatus for treating water according to claim 1, further comprising control means for maintaining the concentration of ammonia contained in the first treated water in a predetermined range by the nitrification means.   The treatment apparatus for water to be treated according to claim 5, wherein the ammonia-oxidizing bacteria are plural kinds of ammonia-oxidizing bacteria which are beta-proteobacteria.   The apparatus for treating water to be treated according to claim 6, wherein the ammonia oxidizing bacteria include those belonging to the genus Nitrosomonas and Nitrosospira.   The control means maintains the concentration of ammonia in a region where the growth rate of the ammonia oxidizing bacteria belonging to the genus halosomonas genus halophilic and salt resistant is larger than the growth rate of the ammonia oxidizing bacteria belonging to the genus Nitrosospira. The processing apparatus of the to-be-processed water of Claim 7. A treatment method of treated water for treating a first treated water containing ammonia and a second treated water containing tetramethylammonium hydroxide,
A nitrification step of oxidizing ammonia contained in the first treated water into nitrite nitrogen and nitrate nitrogen using nitrifying bacteria including ammonia oxidizing bacteria;
Denitrification using nitrite nitrogen and nitrate nitrogen contained in the first treated water treated in the nitrification step using tetramethylammonium hydroxide contained in the second treated water as a hydrogen donor. A denitrification process,
A method for treating water to be treated.

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