JP4817057B2 - Batch treatment of nitrogen-containing water - Google Patents

Batch treatment of nitrogen-containing water Download PDF

Info

Publication number
JP4817057B2
JP4817057B2 JP2006067327A JP2006067327A JP4817057B2 JP 4817057 B2 JP4817057 B2 JP 4817057B2 JP 2006067327 A JP2006067327 A JP 2006067327A JP 2006067327 A JP2006067327 A JP 2006067327A JP 4817057 B2 JP4817057 B2 JP 4817057B2
Authority
JP
Japan
Prior art keywords
methanol
water
nitrogen
concentration
treated
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP2006067327A
Other languages
Japanese (ja)
Other versions
JP2007237145A (en
Inventor
立夫 角野
和一 井坂
創 生田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Plant Technologies Ltd
Original Assignee
Hitachi Plant Technologies Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Plant Technologies Ltd filed Critical Hitachi Plant Technologies Ltd
Priority to JP2006067327A priority Critical patent/JP4817057B2/en
Publication of JP2007237145A publication Critical patent/JP2007237145A/en
Application granted granted Critical
Publication of JP4817057B2 publication Critical patent/JP4817057B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/10—Biological treatment of water, waste water, or sewage

Landscapes

  • Biological Treatment Of Waste Water (AREA)
  • Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)

Description

本発明は窒素含有水の回分処理方法に係り、特に窒素含有水を生物学的に脱窒する回分処理方法に関する。   The present invention relates to a batch processing method for nitrogen-containing water, and more particularly to a batch processing method for biologically denitrifying nitrogen-containing water.

アンモニアなどを含む窒素含有水を生物学的に脱窒処理する最も一般的な方法は、まず、アンモニアを硝化細菌による好気的な硝化反応によって亜硝酸や硝酸に酸化する。次いで亜硝酸や硝酸を脱窒菌による嫌気的な脱窒反応によって窒素ガスにする。脱窒菌は従属栄養性であるため脱窒反応には有機物が必要であり、通常、総窒素濃度に対して３倍程度の有機物を添加している。この従来方法は上記したように、硝化反応のために多量の酸素と、脱窒反応のために多量の有機物を必要とする点で、処理コストが高くなることが問題点として指摘されている。   The most common method for biologically denitrifying nitrogen-containing water containing ammonia or the like first oxidizes ammonia to nitrous acid or nitric acid by an aerobic nitrification reaction by nitrifying bacteria. Next, nitrous acid or nitric acid is converted to nitrogen gas by an anaerobic denitrification reaction by denitrifying bacteria. Since denitrifying bacteria are heterotrophic, organic matter is necessary for the denitrification reaction, and usually about three times as much organic matter as the total nitrogen concentration is added. As described above, this conventional method has been pointed out as a problem in that it requires a large amount of oxygen for the nitrification reaction and a large amount of organic matter for the denitrification reaction.

最近では生物学的な脱窒処理を効率よく安価に行うために、嫌気性アンモニア酸化法が検討されている。この方法はアンモニアの一部を例えば化１に示した硝化反応によって亜硝酸に変換する。次に、残りのアンモニアと生成した亜硝酸とを嫌気性アンモニア酸化細菌により化２に示した脱窒反応（アナモックス反応）によって脱窒する。

Figure 0004817057
Figure 0004817057
 Recently, an anaerobic ammonia oxidation method has been studied in order to efficiently and inexpensively perform biological denitrification treatment. In this method, a part of ammonia is converted into nitrous acid by the nitrification reaction shown in Chemical Formula 1, for example. Next, the remaining ammonia and the produced nitrous acid are denitrified by the denitrification reaction (anammox reaction) shown in Chemical Formula 2 by anaerobic ammonia oxidizing bacteria.
Figure 0004817057
Figure 0004817057

この方法ではアンモニアの一部のみを亜硝酸にするので、硝化反応に必要な酸素量を大幅に低減できる。また、嫌気性アンモニア酸化細菌は独立栄養性であり、脱窒反応に際して有機物を必要としない。このため、アンモニア含有水を安価に脱窒処理できるといわれている（例えば、特許文献１及び特許文献２参照。）。   In this method, only a part of the ammonia is converted to nitrous acid, so that the amount of oxygen necessary for the nitrification reaction can be greatly reduced. In addition, anaerobic ammonia oxidizing bacteria are autotrophic and do not require organic substances for denitrification. For this reason, it is said that ammonia-containing water can be denitrified at low cost (see, for example, Patent Document 1 and Patent Document 2).

しかしながら、上記の嫌気性アンモニア酸化法では、化２に示したように脱窒反応におけるアンモニアと亜硝酸の反応モル比が１：１．３１である。したがって、この反応モル比が維持できないと、アンモニア又は亜硝酸のいずれか一方が過剰となり、反応後の処理水に残存して処理性能の低下を招く。前記特許文献１及び特許文献２にはこのような技術課題に対処するため方策が記載されているが、処理が複雑となる。   However, in the above-described anaerobic ammonia oxidation method, as shown in Chemical Formula 2, the reaction molar ratio of ammonia and nitrous acid in the denitrification reaction is 1: 1.31. Therefore, if this reaction molar ratio cannot be maintained, either ammonia or nitrous acid becomes excessive and remains in the treated water after the reaction, resulting in a reduction in treatment performance. Although Patent Document 1 and Patent Document 2 describe measures for dealing with such technical problems, the processing is complicated.

化１に示した硝化反応においてもアンモニアのすべてを均一に亜硝酸にすることは至難であり、現実の硝化反応槽では未反応のアンモニアや硝酸が硝化液中にかなりの割合で混入する。すなわち、未反応のアンモニアを少なくするために硝化処理を十分にすると硝化液中の硝酸が多くなる。逆に硝酸の生成を少なくするために硝化処理の程度を抑えると硝化液中のアンモニアが多くなる。このため、上記した反応モル比のバランスが不安定となり、嫌気性アンモニア酸化法の実用化を困難にしている。   Even in the nitrification reaction shown in Chemical Formula 1, it is extremely difficult to uniformly convert all of ammonia into nitrous acid. In an actual nitrification reaction tank, unreacted ammonia and nitric acid are mixed in the nitrification solution in a considerable proportion. That is, if sufficient nitrification treatment is performed to reduce unreacted ammonia, nitric acid in the nitrification solution increases. Conversely, if the degree of nitrification treatment is suppressed to reduce the production of nitric acid, the amount of ammonia in the nitrification solution increases. For this reason, the balance of the reaction molar ratio described above becomes unstable, making it difficult to put the anaerobic ammonia oxidation method into practical use.

また、嫌気性アンモニア酸化法は化２で明らかなように、反応後の処理液に硝酸が残る処理法である。このため、脱窒処理を十分に遂行するためには、従来の一般的な方法と同様に、反応後の処理液をさらに従属栄養性の脱窒菌によって脱窒しなければならないという問題点があった。   The anaerobic ammonia oxidation method is a treatment method in which nitric acid remains in the treated solution after the reaction, as apparent from Chemical Formula 2. Therefore, in order to sufficiently perform the denitrification treatment, there is a problem that the treated solution after the reaction must be further denitrified by heterotrophic denitrification bacteria, as in the conventional general method. It was.

このような嫌気性アンモニア酸化法の問題点に対して、非特許文献１には硝酸還元型嫌気性アンモニア酸化法の可能性を検討した結果が報告されている。この方法では、前記した化１のようにアンモニアを酸化して亜硝酸を生成させるのではなく、硝酸を硝酸還元菌によって還元して亜硝酸を生成させる。硝酸還元菌としては従属栄養性の嫌気性微生物が知られており、最も代表的な硝酸還元菌としては周知の従属栄養性脱窒菌を挙げることができる。この硝酸還元型嫌気性アンモニア酸化法によれば、嫌気性アンモニア酸化細菌と硝酸還元菌を共存させた嫌気反応槽に、アンモニアと硝酸とを含有する被処理水を投入する。すると、硝酸還元菌による亜硝酸の生成反応と、化２で示した脱窒反応（アナモックス反応）が同時に進行し、安定かつ効率のよい脱窒処理を実現することができると考えられる。   In response to such problems of the anaerobic ammonia oxidation method, Non-Patent Document 1 reports the results of examining the possibility of the nitrate reduction type anaerobic ammonia oxidation method. In this method, ammonia is not oxidized to produce nitrous acid as in the above-mentioned chemical formula 1, but nitric acid is produced by reducing nitric acid with nitrate-reducing bacteria. Heterotrophic anaerobic microorganisms are known as nitrate-reducing bacteria, and the most typical nitrate-reducing bacteria include well-known heterotrophic denitrifying bacteria. According to this nitrate reduction type anaerobic ammonia oxidation method, water to be treated containing ammonia and nitric acid is introduced into an anaerobic reaction tank in which anaerobic ammonia oxidizing bacteria and nitrate reducing bacteria coexist. Then, it is thought that the production | generation reaction of nitrous acid by nitrate-reducing bacteria and the denitrification reaction (anammox reaction) shown in Chemical Formula 2 proceed simultaneously, and a stable and efficient denitrification treatment can be realized.

一方、非特許文献２には、嫌気性アンモニア酸化法においてメタノールを添加した場合には、メタノールの毒性によって嫌気性アンモニア酸化細菌の活性が著しく低下するという結果が示されている。
特開２００１−１７０６８４号公報 特開２００４−２７５９９７号公報 角野立夫、他４名、硝酸還元型アナモックス反応の可能性について、平成１７年９月２５日発行、平成１７年度日本生物工学会大会講演要旨集、８１頁 Guven D.et.al.、Propionate 0xidation by and Methanol Inhibition of Anaerobic ammonium-oxidizing Bacteria、2005、Appled and Environmental Microbiology、71、1066-1071 On the other hand, Non-Patent Document 2 shows that when methanol is added in the anaerobic ammonia oxidation method, the activity of the anaerobic ammonia oxidizing bacteria is remarkably reduced due to the toxicity of methanol.
JP 2001-170684 A JP 2004-275997 A Tatsuo Tsunono and 4 others, about the possibility of nitrate-reduced anammox reaction, published on September 25, 2005, Proceedings of the 2005 Annual Meeting of the Japanese Society for Biotechnology, page 81 Guven D.et.al., Propionate 0xidation by and Methanol Inhibition of Anaerobic ammonium-oxidizing Bacteria, 2005, Appled and Environmental Microbiology, 71, 1066-1071

上述のとおり、非特許文献１に記載の硝酸還元型嫌気性アンモニア酸化法は窒素含有水の脱窒処理法として有望な方法であるが、従属栄養性の硝酸還元菌による亜硝酸生成反応を促進させるためには、有機物（水素供与体）を添加する必要がある。水素供与体としては安価で反応性のよいメタノールが一般的に使用される。しかしながら、硝酸還元型嫌気性アンモニア酸化法においてメタノールを添加した場合には、非特許文献２に記載されているように嫌気性アンモニア酸化細菌の活性がメタノールの毒性によって低下し、良好な処理を行うことができない可能性がある。このため、水素供与体として酢酸ナトリウムなどメタノール以外の高価な有機物を使用しなければならず、処理コストの増大を招くという問題点があった。   As described above, the nitrate reduction-type anaerobic ammonia oxidation method described in Non-Patent Document 1 is a promising method for the denitrification treatment of nitrogen-containing water, but promotes the nitrite production reaction by heterotrophic nitrate-reducing bacteria. In order to achieve this, it is necessary to add an organic substance (hydrogen donor). As the hydrogen donor, inexpensive and highly reactive methanol is generally used. However, when methanol is added in the nitrate reduction-type anaerobic ammonia oxidation method, as described in Non-Patent Document 2, the activity of anaerobic ammonia-oxidizing bacteria decreases due to the toxicity of methanol, and good treatment is performed. It may not be possible. For this reason, expensive organic substances other than methanol, such as sodium acetate, must be used as a hydrogen donor, resulting in an increase in processing costs.

本発明の目的は、前記従来技術の問題点を改善し、硝酸還元型嫌気性アンモニア酸化法を採用する際に、水素供与体としてメタノールを使用することが可能な窒素含有水の回分処理方法を提供することにある。   The object of the present invention is to improve the above-mentioned problems of the prior art and to provide a batch treatment method for nitrogen-containing water that can use methanol as a hydrogen donor when adopting a nitrate reduction type anaerobic ammonia oxidation method. It is to provide.

本発明者は、嫌気性アンモニア酸化細菌群の脱窒速度に及ぼす基質濃度特性と、嫌気性アンモニア酸化細菌に対するメタノール阻害の状況を究明することによって、水素供与体としてメタノールを使用した硝酸還元型嫌気性アンモニア酸化法を実現したものである。   The present inventor has investigated the concentration of substrate concentration on the denitrification rate of anaerobic ammonia-oxidizing bacteria and the state of methanol inhibition against anaerobic ammonia-oxidizing bacteria, thereby reducing nitrate-reduced anaerobic using methanol as a hydrogen donor. It realizes the basic ammonia oxidation method.

図１は集積培養した嫌気性アンモニア酸化細菌を用いて各種アンモニア濃度における脱窒速度を測定したデータである。嫌気性アンモニア酸化細菌はアンモニア濃度が高いほど脱窒速度が向上し、Michaelis・Menten型の反応特性を示す。   FIG. 1 shows data obtained by measuring the denitrification rate at various ammonia concentrations using an anaerobic ammonia-oxidizing bacterium cultivated in an integrated manner. Anaerobic ammonia-oxidizing bacteria show higher Michael denitrification rate and higher Michaelis / Menten-type reaction characteristics.

図２は各種濃度のメタノールを添加した場合における嫌気性アンモニア酸化反応の脱窒活性比を測定したデータである。図中、グラフａは嫌気性アンモニア酸化細菌をポリエチレングリコールで包括固定化した包括固定化担体を用いた場合、グラフｂは嫌気性アンモニア酸化細菌を浮遊状態で用いた場合を示す。いずれの場合でもメタノールが１００ｍｇ／Ｌ以上で脱窒活性比が低下し、メタノール阻害が大きくなる。また、包括固定化担体を用いた方が浮遊状態よりも脱窒活性比が相対的に大きくなり、メタノールに対する耐性が大きいことを見いだした。   FIG. 2 shows data obtained by measuring the denitrification activity ratio of the anaerobic ammonia oxidation reaction when various concentrations of methanol were added. In the figure, graph a shows a case where an entrapping immobilization support in which anaerobic ammonia oxidizing bacteria are entrapped and immobilized with polyethylene glycol is used, and graph b shows a case where anaerobic ammonia oxidizing bacteria are used in a floating state. In any case, when the amount of methanol is 100 mg / L or more, the denitrification activity ratio decreases and methanol inhibition increases. In addition, it was found that the use of the entrapping immobilization support has a relatively large denitrification activity ratio and a greater resistance to methanol than in the suspended state.

表１は集積培養した嫌気性アンモニア酸化細菌を保持した担体を用いて各種基質濃度における脱窒速度を測定したデータである。メタノール濃度は一定の１００ｍｇ／Ｌとし、付着担体と包括固定化担体について測定し、測定結果はメタノールを添加しない場合との相対活性値で示した。アンモニア濃度が８０ｍｇ／Ｌ以下の時には顕著なメタノール阻害が認められ、アンモニア濃度が高くなるに従ってメタノール阻害が少なくなる傾向がある。このような傾向を示す理由は、嫌気性アンモニア酸化細菌に対してメタノールがアンモニアに拮抗して阻害しているためと考えられる。また、付着担体に比べて包括固定化担体の方がメタノール阻害が少なく、メタノールに対する耐性が大きいことを見いだした。

Figure 0004817057
Table 1 shows data obtained by measuring the denitrification rate at various substrate concentrations using a carrier holding anaerobic ammonia-oxidizing bacteria accumulated and cultured. The methanol concentration was fixed at 100 mg / L, and the adhesion carrier and the entrapping immobilization carrier were measured. The measurement results were shown as relative activity values when no methanol was added. When the ammonia concentration is 80 mg / L or less, significant methanol inhibition is observed, and the methanol inhibition tends to decrease as the ammonia concentration increases. The reason for this tendency is considered to be that methanol antagonizes and inhibits anaerobic ammonia-oxidizing bacteria. It was also found that the entrapping immobilization carrier had less methanol inhibition and greater resistance to methanol than the adherent carrier.
Figure 0004817057

図３は模擬廃水の回分処理結果を示すデータである。模擬廃水はアンモニア性窒素濃度が５００ｍｇ／Ｌ、硝酸性窒素濃度が７００ｍｇ／Ｌの無機廃水を使用した。従属栄養性の硝酸還元菌である嫌気性脱窒菌と嫌気性アンモニア酸化細菌とを共存させた包括固定化担体を作成し、この包括固定化担体を充填率３０％で投入した反応槽に上記模擬廃水を張り込み、メタノール初期濃度を変化させてトータル窒素（Ｔ−Ｎ）除去率を調べた。メタノール初期濃度が５００ｍｇ／Ｌ以下では高いＴ−Ｎ除去率を示したが、５００ｍｇ／Ｌを超えるとＴ−Ｎ除去率が急激に低下した。   FIG. 3 is data showing the result of batch treatment of simulated wastewater. As the simulated wastewater, an inorganic wastewater having an ammonia nitrogen concentration of 500 mg / L and a nitrate nitrogen concentration of 700 mg / L was used. A entrapped immobilization support coexisting anaerobic denitrifying bacteria and anaerobic ammonia-oxidizing bacteria, which are heterotrophic nitrate-reducing bacteria, was prepared, and the above simulation was conducted in a reaction tank charged with the entrapped immobilization support at a filling rate of 30% Waste water was put in and the initial concentration of methanol was changed to examine the total nitrogen (TN) removal rate. When the initial methanol concentration was 500 mg / L or less, a high TN removal rate was exhibited, but when it exceeded 500 mg / L, the TN removal rate rapidly decreased.

本発明はかかる知見に基づいてなされたものであり、上記目的を達成するための本発明に係る窒素含有水の回分処理方法は、嫌気性アンモニア酸化細菌と従属栄養性の硝酸還元菌とを共存させた反応槽内にアンモニアと硝酸を含有する被処理水を張り込み、該被処理水を前記嫌気性アンモニア酸化細菌及び硝酸還元菌と接触させることによって回分式に脱窒処理する窒素含有水の回分処理方法において、前記反応槽内における被処理水のメタノール初期濃度が５００ｍｇ／Ｌ以下となる条件でメタノールを初期添加し、前記メタノールを初期添加した後に、前記反応槽内の被処理水のメタノール濃度が１００ｍｇ／Ｌ以下で、かつＣ／Ｎ比が０．１以上を維持するように前記メタノールを随時に添加することを特徴とする。 The present invention has been made on the basis of such findings, and the batch treatment method for nitrogen-containing water according to the present invention for achieving the above object is the coexistence of anaerobic ammonia-oxidizing bacteria and heterotrophic nitrate-reducing bacteria. A batch of nitrogen-containing water that is denitrified in a batch manner by placing water to be treated containing ammonia and nitric acid in the reaction tank, and bringing the water to be treated into contact with the anaerobic ammonia oxidizing bacteria and nitrate reducing bacteria. In the treatment method, methanol is initially added under the condition that the initial concentration of methanol in the water to be treated in the reaction tank is 500 mg / L or less, and after the initial addition of methanol, the methanol concentration of the water to be treated in the reaction tank Is 100 mg / L or less, and the methanol is added as needed so that the C / N ratio is maintained at 0.1 or more .

また、本発明に係る窒素含有水の回分処理方法は、前記メタノールを初期添加した後に、前記反応槽内の被処理水のメタノール濃度が１００ｍｇ／Ｌ以下、かつＣ／Ｎ比が０．１以上を維持するようにメタノールを随時に添加することを特徴とする。なお、本発明においてＣ／Ｎ比とは被処理水中の有機性炭素濃度Ｃと亜硝酸性窒素濃度Ｎの比率を意味している。   Further, in the batch treatment method for nitrogen-containing water according to the present invention, the methanol concentration of water to be treated in the reaction tank is 100 mg / L or less and the C / N ratio is 0.1 or more after the initial addition of the methanol. It is characterized by adding methanol at any time so as to maintain the above. In the present invention, the C / N ratio means the ratio between the organic carbon concentration C and the nitrite nitrogen concentration N in the water to be treated.

上記方法を実施するにあたっては、前記嫌気性アンモニア酸化細菌と従属栄養性の硝酸還元菌を高分子ゲルの内部に包括固定した状態で前記反応槽内に共存させることが望ましい。また、前記反応槽の前段で前記被処理水のアンモニア性窒素と硝酸性窒素の濃度比を調整することが望ましい。   In carrying out the above method, it is desirable that the anaerobic ammonia-oxidizing bacteria and heterotrophic nitrate-reducing bacteria coexist in the reaction tank in a state of being comprehensively fixed inside the polymer gel. Further, it is desirable to adjust the concentration ratio of ammonia nitrogen and nitrate nitrogen of the water to be treated in the previous stage of the reaction tank.

本発明に係る窒素含有水の回分処理方法によれば、窒素含有水を硝酸還元型嫌気性アンモニア酸化法によって回分式に脱窒処理する際に、反応槽内における被処理水のメタノール初期濃度が５００ｍｇ／Ｌ以下となる条件でメタノールを初期添加するようにした。このため、嫌気性アンモニア酸化細菌に対するメタノール阻害を抑制しつつ、水素供与体として安価なメタノールを使用した回分処理方法を実現することができる。   According to the batch treatment method for nitrogen-containing water according to the present invention, when the nitrogen-containing water is batch-denitrified by the nitrate reduction type anaerobic ammonia oxidation method, the initial concentration of methanol in the water to be treated in the reaction tank is Methanol was initially added under the condition of 500 mg / L or less. Therefore, it is possible to realize a batch processing method using inexpensive methanol as a hydrogen donor while suppressing methanol inhibition against anaerobic ammonia oxidizing bacteria.

また、メタノールを初期添加した後に、反応槽内の被処理水のメタノール濃度が１００ｍｇ／Ｌ以下、かつＣ／Ｎ比が０．１以上を維持するようにメタノールを随時に添加することによって、被処理水のメタノール濃度を過不足なく維持することができ、より一層、窒素除去率を高めることができる。
また、嫌気性アンモニア酸化細菌と硝酸還元菌を高分子ゲルの内部に包括固定した状態で前記反応槽内に共存させると、脱窒速度に優れた窒素含有水の処理が可能になる。 In addition, after initial addition of methanol, methanol is added at any time so that the concentration of methanol in the water to be treated in the reaction vessel is 100 mg / L or less and the C / N ratio is 0.1 or more. The methanol concentration of treated water can be maintained without excess and deficiency, and the nitrogen removal rate can be further increased.
Further, when anaerobic ammonia-oxidizing bacteria and nitrate-reducing bacteria coexist in the polymer gel and coexist in the reaction tank, it is possible to treat nitrogen-containing water with an excellent denitrification rate.

さらに、本発明に係る窒素含有水の処理装置として、反応槽の前段で被処理水のアンモニア性窒素と硝酸性窒素の濃度比を調整すると、被処理水におけるアンモニア性窒素と硝酸性窒素の濃度比を例えば１対（１．２〜１．５）に調整することが可能になり、反応槽における硝酸還元型嫌気性アンモニア酸化反応をバランスよく促進させることができる。   Further, as the nitrogen-containing water treatment apparatus according to the present invention, the concentration of ammonia nitrogen and nitrate nitrogen in the water to be treated is adjusted by adjusting the concentration ratio of ammonia nitrogen and nitrate nitrogen in the water before the reaction tank. The ratio can be adjusted to, for example, one pair (1.2 to 1.5), and the nitrate-reducing anaerobic ammonia oxidation reaction in the reaction tank can be promoted in a well-balanced manner.

図４は本発明に係る窒素含有水の回分処理方法の第１実施形態を示す系統図である。反応槽１０にはアンモニアと硝酸を含有する被処理水１２が１回分に相当する量で張り込まれる。反応槽１０内には担体１４が投入されている。担体１４は嫌気性アンモニア酸化細菌と従属栄養性の硝酸還元菌とを高濃度に固定化したものである。   FIG. 4 is a system diagram showing a first embodiment of the batch treatment method for nitrogen-containing water according to the present invention. A water to be treated 12 containing ammonia and nitric acid is put into the reaction tank 10 in an amount corresponding to one batch. A carrier 14 is introduced into the reaction tank 10. The carrier 14 is obtained by immobilizing anaerobic ammonia-oxidizing bacteria and heterotrophic nitrate-reducing bacteria at high concentrations.

担体１４の作成方法としては、付着固定と包括固定の２つの方法を用いることができる。付着固定では球状、筒状、紐状、ゲル状、不織布状材料などに上記の菌を付着させたものであり、凹凸の多い材料を用いると菌が付着しやすく、菌を高濃度に固定でき、脱窒能が向上する。包括固定ではモノマ又はプレポリマの固定化材料と菌を混合した混合液を重合し、高分子ゲルの内部に菌を包括固定する。モノマ材料としてはアクリルアミド、メチレンビスアクリルアミド、トリアクリルフォルマールなどがよい。プレポリマ材料としてはポリエチレングリコールジアクリレートやポリエチレングリコールメタアクリレートがよく、その誘導体を用いることもできる。形状は付着固定と同様に凹凸の多いものが被処理水との接触効率がよく、脱窒能が向上する。   As a method for producing the carrier 14, two methods of adhesion fixation and entrapping fixation can be used. Adhesion fixation is a material in which the above bacteria are adhered to a spherical, cylindrical, string-like, gel-like, non-woven material, etc. If a material with many irregularities is used, the bacteria are likely to adhere, and the bacteria can be fixed at a high concentration. , Denitrification ability is improved. In entrapping immobilization, a mixed solution in which a monomer or prepolymer immobilization material and bacteria are mixed is polymerized, and the bacterium is encapsulated and fixed inside the polymer gel. As the monomer material, acrylamide, methylenebisacrylamide, triacryl formal and the like are preferable. The prepolymer material is preferably polyethylene glycol diacrylate or polyethylene glycol methacrylate, and derivatives thereof can also be used. As in the case of adhesion and fixation, the shape with many irregularities has good contact efficiency with the water to be treated, and the denitrification ability is improved.

反応槽１０の底部には攪拌機１８が配設され、この攪拌機１８を駆動することにより、反応槽１０内は嫌気状態に維持されるとともに、張り込んだ被処理水１２と担体１４とを流動させる。また、反応槽１０の底部には処理水の排出口１６が設けられ、この排出口１６には担体１４が処理水に同伴して流出しないように、担体分離用のスクリーン２０が配置されている。また、排出口１６には排出弁２２を備えた処理水の排出管２４が接続している。   A stirrer 18 is disposed at the bottom of the reaction tank 10, and by driving the stirrer 18, the inside of the reaction tank 10 is maintained in an anaerobic state, and the treated water 12 and the carrier 14 that are stuck are flowed. . A treated water discharge port 16 is provided at the bottom of the reaction tank 10, and a carrier separation screen 20 is disposed at the discharge port 16 so that the carrier 14 does not flow out along with the treated water. . Further, a discharge pipe 24 of treated water having a discharge valve 22 is connected to the discharge port 16.

さらに、反応槽１０には張り込んだ被処理水１２の窒素濃度を検出可能な窒素濃度計２６とメタノール濃度を検出可能なメタノール濃度計２８が配設されている。これらの濃度計の検出値は制御器３０に送信され、制御器３０では送信された被処理水１２の窒素濃度及びメタノール濃度に応じて、メタノール添加手段３２に設けた電磁弁を開閉させ、反応槽１０内に添加するメタノール量を制御する。   Further, a nitrogen concentration meter 26 capable of detecting the nitrogen concentration of the water 12 to be treated and a methanol concentration meter 28 capable of detecting the methanol concentration are disposed in the reaction tank 10. The detected values of these densitometers are transmitted to the controller 30, and the controller 30 opens and closes an electromagnetic valve provided in the methanol addition means 32 in accordance with the transmitted nitrogen concentration and methanol concentration of the treated water 12 to react. The amount of methanol added to the tank 10 is controlled.

上記構成の反応槽１０内では供給された被処理水１２と担体１４とが流動状態で接触する。その結果、担体１４に固定された硝酸還元菌の還元反応によって、被処理水１２中の硝酸はメタノール添加手段３２から添加されたメタノールを水素供与体として還元され、亜硝酸に変換される。生成した亜硝酸は担体１４に固定された嫌気性アンモニア酸化細菌による脱窒反応（アナモックス反応）によって、脱窒される。この脱窒反応（アナモックス反応）では化２に示したように硝酸が一部、生成するが、生成した硝酸は直ちに硝酸還元菌によって還元され再び亜硝酸に変換されるので、反応槽１０に硝酸が蓄積することはない。このように本実施形態の窒素含有水の処理方法及び装置によれば、担体１４に固定して共存させた硝酸還元菌による還元反応と嫌気性アンモニア酸化細菌による脱窒反応が同時に進行し、被処理水１２中の硝酸とアンモニアが段階的に脱窒される。回分処理が終了した後は排出弁２２を開放し、排出管２４から１回分に相当する量の処理水を反応槽１０から排出する。そして、再び被処理水１２を反応槽１０に張り込んで、次の回分処理を繰り返す。なお、回分処理にあたっては反応槽１０内の被処理水１２を全量入れ替える必要はなく、被処理水１２の窒素濃度などに応じて入れ替え量を任意に選択することができる。   In the reaction tank 10 configured as described above, the supplied water to be treated 12 and the carrier 14 are in contact with each other in a fluid state. As a result, the nitric acid in the water to be treated 12 is reduced by using the methanol added from the methanol adding means 32 as a hydrogen donor by the reduction reaction of the nitrate reducing bacteria fixed on the carrier 14, and converted into nitrous acid. The produced nitrous acid is denitrified by a denitrification reaction (anammox reaction) by an anaerobic ammonia oxidizing bacterium fixed to the carrier 14. In this denitrification reaction (anammox reaction), a part of nitric acid is produced as shown in Chemical Formula 2, but the produced nitric acid is immediately reduced by nitrate-reducing bacteria and converted to nitrous acid again. Will not accumulate. Thus, according to the treatment method and apparatus for nitrogen-containing water of this embodiment, the reduction reaction by nitrate-reducing bacteria immobilized on the carrier 14 and the denitrification reaction by anaerobic ammonia-oxidizing bacteria proceed simultaneously, Nitric acid and ammonia in the treated water 12 are denitrified stepwise. After the batch processing is completed, the discharge valve 22 is opened, and the amount of treated water corresponding to one batch is discharged from the reaction tank 10 through the discharge pipe 24. And the to-be-processed water 12 is stuck in the reaction tank 10 again, and the next batch process is repeated. In batch processing, it is not necessary to replace the entire amount of the water to be treated 12 in the reaction tank 10, and the replacement amount can be arbitrarily selected according to the nitrogen concentration of the water to be treated 12.

反応槽１０においては、被処理水１２のメタノール濃度の管理が重要である。前記したように嫌気性アンモニア酸化細菌はメタノール阻害を受け易い。このため、アンモニアと拮抗関係にあるメタノールの濃度を適正に管理し、メタノール初期濃度を５００ｍｇ／Ｌ以下とする。また、メタノールを初期添加した後には、必要に応じて反応槽１０内の被処理水１２のメタノール濃度が１００ｍｇ／Ｌ以下で、かつＣ／Ｎ比が０．１以上を維持するようにメタノールを随時に添加する。   In the reaction tank 10, it is important to manage the methanol concentration of the water to be treated 12. As described above, anaerobic ammonia oxidizing bacteria are susceptible to methanol inhibition. For this reason, the concentration of methanol having an antagonistic relationship with ammonia is appropriately managed, and the initial concentration of methanol is set to 500 mg / L or less. In addition, after the initial addition of methanol, methanol is added so that the methanol concentration of the water to be treated 12 in the reaction tank 10 is 100 mg / L or less and the C / N ratio is 0.1 or more as necessary. Add as needed.

図５はメタノール濃度の管理例を示したモデル図である。図中、ケース１は被処理水１２のアンモニア初期濃度が高濃度の場合を示す。被処理水１２のアンモニア濃度が５００ｍｇ／Ｌ以上の場合では、表１に示したようにメタノール阻害をほとんど受けない。したがって、回分処理の初期ではメタノール濃度が例えば４００ｍｇ／Ｌ程度となるようになるべく多量のメタノールを添加する。添加されたメタノールは硝酸還元菌による還元反応において水素供与体として消費され、回分処理の過程でメタノール濃度が徐々に低下する。同時に被処理水１２のアンモニア濃度や硝酸濃度も徐々に低下する。   FIG. 5 is a model diagram showing an example of management of methanol concentration. In the figure, Case 1 shows a case where the initial ammonia concentration of the water to be treated 12 is high. When the ammonia concentration of the water to be treated 12 is 500 mg / L or more, as shown in Table 1, methanol is hardly affected. Therefore, at the initial stage of batch processing, as much methanol as possible is added so that the methanol concentration becomes, for example, about 400 mg / L. The added methanol is consumed as a hydrogen donor in the reduction reaction by nitrate-reducing bacteria, and the methanol concentration gradually decreases during the batch process. At the same time, the ammonia concentration and nitric acid concentration of the water to be treated 12 are gradually decreased.

水素供与体としてメタノールの濃度が低下すると還元反応が不活発となり、脱窒反応にも悪影響を与える。したがって、経過時間ａでは被処理水１２におけるＣ／Ｎ比が少なくとも０．１を維持するようにメタノールを補充する。経過時間ａではそれまでの脱窒反応によって、被処理水１２のアンモニア濃度が例えば３００ｍｇ／Ｌに低下しており、表１に示したように嫌気性アンモニア酸化細菌がメタノール阻害を受ける可能性が大きくなる。したがって、経過時間ａでは被処理水１２のメタノール濃度が１００ｍｇ／Ｌ程度となるようにメタノールの添加量を調整する。   When the concentration of methanol as a hydrogen donor is lowered, the reduction reaction becomes inactive, which also adversely affects the denitrification reaction. Therefore, methanol is replenished so that the C / N ratio in the treated water 12 is maintained at least 0.1 at the elapsed time a. At the elapsed time a, the ammonia concentration of the water 12 to be treated has been reduced to, for example, 300 mg / L due to the denitrification reaction so far, and as shown in Table 1, there is a possibility that the anaerobic ammonia-oxidizing bacteria are subject to methanol inhibition. growing. Accordingly, the amount of methanol added is adjusted so that the methanol concentration of the treated water 12 is about 100 mg / L at the elapsed time a.

経過時間ｂでも被処理水１２におけるＣ／Ｎ比が少なくとも０．１を維持するようにメタノールを補充する。経過時間ｂではそれまでの脱窒反応によって、被処理水１２のアンモニア濃度がより一層、低下しており、例えば１００ｍｇ／Ｌになっている。したがって、経過時間ｂでは被処理水１２のメタノール濃度が５０ｍｇ／Ｌ程度となるようにメタノールの添加量を調整する。   Methanol is replenished so that the C / N ratio in the treated water 12 is maintained at least 0.1 even at the elapsed time b. At the elapsed time b, the ammonia concentration of the water to be treated 12 is further reduced by the denitrification reaction so far, and is, for example, 100 mg / L. Therefore, the amount of methanol added is adjusted so that the methanol concentration of the water to be treated 12 is about 50 mg / L at the elapsed time b.

図５のケース２は被処理水１２のアンモニア初期濃度が２００ｍｇ／Ｌ程度の中濃度の場合を示す。このケースではメタノール初期濃度が１００ｍｇ／Ｌを超えると、表１に示したように嫌気性アンモニア酸化細菌がメタノール阻害を受ける可能性が大きくなる。したがって、メタノール初期濃度が８０ｍｇ／Ｌ程度となるようにメタノールの添加量を調整する。以下、ケース１と同様の考え方で水素供与体としてのメタノールが不足することが懸念される経過時間ｃでは、被処理水１２のメタノール濃度が４０ｍｇ／Ｌ程度となるようにメタノールの添加量を調整する。   Case 2 in FIG. 5 shows a case where the initial concentration of ammonia in the treated water 12 is a medium concentration of about 200 mg / L. In this case, when the initial methanol concentration exceeds 100 mg / L, the anaerobic ammonia-oxidizing bacteria are more likely to be inhibited by methanol as shown in Table 1. Therefore, the amount of methanol added is adjusted so that the initial methanol concentration is about 80 mg / L. Hereinafter, the amount of methanol added is adjusted so that the methanol concentration of the water to be treated 12 is about 40 mg / L at the elapsed time c when there is a concern that methanol as a hydrogen donor will be insufficient in the same way as in Case 1. To do.

上記したメタノールの添加量の調整は、前記したように窒素濃度計２６とメタノール濃度計２８で検出した被処理水１２の窒素濃度及びメタノール濃度に応じて、制御器３０がメタノール添加手段３２の電磁弁３４を制御することによって実施する。   As described above, the controller 30 adjusts the amount of methanol to be added by the controller 30 according to the nitrogen concentration and methanol concentration of the water 12 to be treated detected by the nitrogen concentration meter 26 and the methanol concentration meter 28. This is done by controlling the valve 34.

本実施形態の窒素含有水の回分処理方法は、被処理水１２が有機物をほとんど含まない無機系の窒素含有水である場合に特に有効であるが、被処理水１２が有機系の窒素含有水に対しても適用することができる。被処理水１２が有機系の場合には、被処理水１２中の有機物を還元反応における水素供与体として利用することができるので、その分、メタノールの添加量を減らすことができる。例えば、被処理水１２中の有機物量が多い場合には運転初期ではメタノールを添加せず、還元反応に必要な水素供与体の全量を被処理水１２中の有機物で賄う。そして、回分処理の経過途中で不足する水素供与体をメタノールの添加によって補うようにすればよい。このような場合には図４に示したメタノール濃度計２８に替えて有機炭素計を設置し、この有機炭素計で検出した被処理水１２中の有機性炭素濃度に応じて、メタノールの添加量を調整し、反応槽１０内の被処理水１２のメタノール濃度が１００ｍｇ／Ｌ以下で、かつＣ／Ｎ比が０．１以上を維持するように管理することが望ましい。   The batch treatment method for nitrogen-containing water according to the present embodiment is particularly effective when the water to be treated 12 is inorganic nitrogen-containing water that contains almost no organic matter, but the water to be treated 12 is organic nitrogen-containing water. It can also be applied to. When the water to be treated 12 is organic, the organic matter in the water to be treated 12 can be used as a hydrogen donor in the reduction reaction, so that the amount of methanol added can be reduced accordingly. For example, when the amount of organic matter in the treated water 12 is large, methanol is not added at the initial stage of operation, and the entire amount of hydrogen donor necessary for the reduction reaction is covered by the organic matter in the treated water 12. And what is necessary is just to make up for the hydrogen donor insufficient in the course of batch processing by addition of methanol. In such a case, an organic carbon meter is installed instead of the methanol concentration meter 28 shown in FIG. 4, and the amount of methanol added according to the organic carbon concentration in the treated water 12 detected by the organic carbon meter. It is desirable to manage such that the methanol concentration of the water 12 to be treated in the reaction vessel 10 is 100 mg / L or less and the C / N ratio is maintained at 0.1 or more.

上述のとおり、本実施形態の窒素含有水の回分処理方法によれば、反応槽１０内には嫌気性アンモニア酸化細菌と従属栄養性の硝酸還元菌とを高濃度に固定化した担体１４が保持されている。そして、メタノール添加手段３２からのメタノール添加量を被処理水１２の窒素濃度に応じて添加するようにしている。すなわち、嫌気性アンモニア酸化細菌がメタノール阻害を受け難いように、かつ、被処理水１２のＣ／Ｎを０．１以上に維持して従属栄養性の硝酸還元菌が還元反応を行うために必要な水素供与体が不足しないようにメタノールを過不足なく添加することができる。   As described above, according to the batch treatment method of nitrogen-containing water of the present embodiment, the carrier 14 in which the anaerobic ammonia-oxidizing bacteria and the heterotrophic nitrate-reducing bacteria are immobilized at a high concentration is retained in the reaction tank 10. Has been. Then, the amount of methanol added from the methanol adding means 32 is added according to the nitrogen concentration of the water 12 to be treated. That is, it is necessary for the anaerobic ammonia oxidizing bacteria to be less susceptible to methanol inhibition and for the heterotrophic nitrate-reducing bacteria to carry out the reduction reaction while maintaining the C / N of the treated water 12 at 0.1 or more. Methanol can be added without excess or deficiency so that a sufficient hydrogen donor is not insufficient.

このため、硝酸還元型嫌気性アンモニア酸化法を採用する際に、水素供与体として安価なメタノールを使用することが可能となり、経済性に優れた窒素含有水の回分処理方法を実現することができる。特に、担体１４として嫌気性アンモニア酸化細菌と硝酸還元菌を高分子ゲルの内部に包括固定した包括固定化担体を用いた場合には、メタノール阻害が少なく、メタノールに対する耐性が大きいので有効である。   For this reason, when adopting the nitrate reduction type anaerobic ammonia oxidation method, it becomes possible to use inexpensive methanol as a hydrogen donor, and it is possible to realize an economical batch treatment method for nitrogen-containing water. . In particular, when a entrapping immobilization carrier in which anaerobic ammonia-oxidizing bacteria and nitrate-reducing bacteria are entrapped and immobilized inside a polymer gel is used as the carrier 14, it is effective because there is little methanol inhibition and high resistance to methanol.

図６は本発明に係る窒素含有水の回分処理方法の第２実施形態を示す系統図である。図６において図４と同一の符号を付した要素は前記第１実施形態と同様の要素であり、説明を省略する。本実施形態は原水としての被処理水１２Ａが例えばアンモニアのみを含んでおり、硝酸を含んでいない場合に適用される。このような場合には、被処理水１２Ａの一部を硝化槽４０に導き、被処理水１２Ａ中のアンモニアを硝酸（亜硝酸を含む。）にする。硝化槽４０としては従来技術として周知の各種の生物学的な硝化反応槽を用いることができる。この硝化槽４０で硝化された硝化液１２Ｂを被処理水１２Ａの残部と混合し、被処理水１２として反応槽１０に供給する。被処理水１２におけるアンモニア性窒素と硝酸性窒素の濃度比を１対（１．２〜１．５）に調整することによって、反応槽１０における硝酸還元型嫌気性アンモニア酸化反応がバランスよく促進する。   FIG. 6 is a system diagram showing a second embodiment of the batch treatment method for nitrogen-containing water according to the present invention. In FIG. 6, elements denoted by the same reference numerals as those in FIG. 4 are the same elements as in the first embodiment, and description thereof is omitted. This embodiment is applied when the water 12A to be treated as raw water contains, for example, only ammonia and no nitric acid. In such a case, part of the treated water 12A is guided to the nitrification tank 40, and ammonia in the treated water 12A is converted to nitric acid (including nitrous acid). As the nitrification tank 40, various biological nitrification reaction tanks known in the prior art can be used. The nitrification liquid 12B nitrified in the nitrification tank 40 is mixed with the remainder of the water to be treated 12A and supplied to the reaction tank 10 as the water to be treated 12. By adjusting the concentration ratio of ammonia nitrogen and nitrate nitrogen in the water to be treated 12 to 1 (1.2 to 1.5), the nitrate reduction type anaerobic ammonia oxidation reaction in the reaction tank 10 is promoted in a well-balanced manner. .

なお、本実施形態では反応槽１０には前記第１実施形態で説明した窒素濃度計２６とメタノール濃度計２８を設置せずに、回分処理中に反応槽１０内の被処理水１２を適当なタイミングでサンプリングし、サンプリング水の分析結果に基づき、第１実施形態と同様の考え方でメタノール添加手段３２からのメタノール添加量を調整する。   In the present embodiment, the water to be treated 12 in the reaction tank 10 is appropriately disposed during batch processing without installing the nitrogen concentration meter 26 and the methanol concentration meter 28 described in the first embodiment in the reaction tank 10. Sampling is performed at the timing, and the amount of methanol added from the methanol addition unit 32 is adjusted based on the analysis result of the sampling water in the same manner as in the first embodiment.

実施例１
アンモニアと亜硝酸で集積培養し、嫌気性アンモニア酸化細菌濃度が８×１０８cell／ｍＬで脱窒速度１．２ｋｇ−Ｎ／ｍ３／日の能力を持った集積培養汚泥を実験に供試した。この集積培養汚泥と従属栄養性の硝酸還元菌である脱窒菌を含んだ活性汚泥とを模擬廃水を張り込んだ反応容器に投入し、ＭＬＳＳとして４０００ｍｇ／Ｌ、総菌数数４×１０８cell／ｍＬ、嫌気性アンモニア酸化細菌濃度が８×１０５cell／ｍＬの条件で運転を開始した。なお、汚泥は担体に固定せずフリー状態の浮遊式とした。 Example 1
Accumulated culture sludge with anaerobic ammonia-oxidizing bacteria concentration of 8 × 10 8 cells / mL and denitrification rate of 1.2 kg-N / m 3 / day for the experiment did. This accumulated culture sludge and activated sludge containing denitrifying bacteria that are heterotrophic nitrate-reducing bacteria are put into a reaction vessel filled with simulated wastewater, and are set to 4000 mg / L as MLSS, and the total number of bacteria 4 × 10 8 cells. The operation was started under the conditions of anaerobic ammonia oxidizing bacteria concentration of 8 × 10 5 cells / mL. The sludge was not fixed to the carrier, but a free floating type.

模擬廃水は、トータル窒素（Ｔ−Ｎ）濃度が１２００ｍｇ／Ｌ（アンモニア性窒素濃度５００ｍｇ／Ｌ、硝酸性窒素７００ｍｇ／Ｌ）の無機廃水であり、この無機廃水にメタノール初期濃度が３００ｍｇ／Ｌとなるようにメタノールを添加して運転を開始した。さらに、運転開始後、１日目、１．５日目、２日目にメタノールを各１００ｍｇ／Ｌ添加した。また、比較例としてメタノール初期濃度を６００ｍｇ／Ｌとし、以降はメタノールを添加しない運転を併せて行った。   The simulated wastewater is an inorganic wastewater having a total nitrogen (TN) concentration of 1200 mg / L (ammonia nitrogen concentration 500 mg / L, nitrate nitrogen 700 mg / L). The initial concentration of methanol is 300 mg / L in this inorganic wastewater. Methanol was added so that the operation started. Further, 100 mg / L each of methanol was added on the first day, 1.5th day, and second day after the start of operation. In addition, as a comparative example, the initial methanol concentration was 600 mg / L, and thereafter, the operation without adding methanol was also performed.

図７は実験結果を示すグラフである。本発明方法ではＴ−Ｎ濃度が初期の１２００ｍｇ／Ｌから３日目には約２００ｍｇ／Ｌにまで低下し、Ｔ−Ｎ除去率８４％を示した。一方、比較例は３日目におけるＴ−Ｎ除去率が４５％程度であった。比較例のＴ−Ｎ除去率が低い理由は、嫌気性アンモニア酸化細菌が初期のメタノール添加によってメタノール阻害を受け、活性が低下したためと考えられる。   FIG. 7 is a graph showing experimental results. In the method of the present invention, the TN concentration decreased from the initial 1200 mg / L to about 200 mg / L on the third day, and showed a TN removal rate of 84%. On the other hand, in the comparative example, the TN removal rate on the third day was about 45%. The reason why the TN removal rate of the comparative example is low is considered to be that the anaerobic ammonia-oxidizing bacteria were subjected to methanol inhibition by the initial addition of methanol, and the activity was reduced.

実施例２
アンモニアと亜硝酸で集積培養し、嫌気性アンモニア酸化細菌濃度が８×１０８cell／ｍＬで脱窒速度１．２ｋｇ−Ｎ／ｍ３／日の能力を持った集積培養汚泥を実験に供試した。この集積培養汚泥と従属栄養性の硝酸還元菌である脱窒菌を含んだ活性汚泥とを混合し、この混合汚泥がＭＬＳＳとして２％となるようにポリエチレングリコールに包括固定し、３ｍｍ角の包括固定化担体を得た。この担体の嫌気性アンモニア酸化細菌濃度は４×１０８cell／ｍＬ、脱窒菌数は８×１０７cell／ｍＬであり、この担体を図４に示した反応槽に充填率４０％で投入し、模擬廃水による回分処理実験を行った。 Example 2
Accumulated culture sludge with anaerobic ammonia-oxidizing bacteria concentration of 8 × 10 8 cells / mL and denitrification rate of 1.2 kg-N / m 3 / day for the experiment did. This concentrated culture sludge is mixed with activated sludge containing denitrifying bacteria that are heterotrophic nitrate-reducing bacteria, and this mixed sludge is comprehensively fixed in polyethylene glycol so that the mixed sludge becomes 2%, and 3 mm square comprehensive fixed A modified carrier was obtained. The concentration of anaerobic ammonia-oxidizing bacteria in this carrier is 4 × 10 8 cells / mL, and the number of denitrifying bacteria is 8 × 10 7 cells / mL. This carrier is introduced into the reaction tank shown in FIG. 4 at a filling rate of 40%. A batch treatment experiment with simulated wastewater was conducted.

模擬廃水はトータル窒素（Ｔ−Ｎ）濃度が３０００ｍｇ／Ｌ（アンモニア性窒素濃度１４００ｍｇ／Ｌ、硝酸性窒素１６００ｍｇ／Ｌ）の無機廃水であり、この無機廃水にメタノール初期濃度が３００ｍｇ／Ｌとなるようにメタノールを添加して運転を開始した。さらに、運転開始後、被処理水のメタノール濃度が１００ｍｇ／Ｌに達した時点からはメタノール濃度が９０〜１００ｍｇ／Ｌを維持するようにメタノールの添加量を自動制御した。また、比較例としてメタノール初期濃度を３００ｍｇ／Ｌとし、２４時間後にメタノールを３００ｍｇ／Ｌ添加した運転を併せて行った。   The simulated wastewater is an inorganic wastewater having a total nitrogen (TN) concentration of 3000 mg / L (ammonia nitrogen concentration 1400 mg / L, nitrate nitrogen 1600 mg / L). The initial concentration of methanol in this inorganic wastewater is 300 mg / L. The operation was started by adding methanol. Furthermore, after the start of operation, the amount of methanol added was automatically controlled so that the methanol concentration was maintained at 90 to 100 mg / L from the time when the methanol concentration of the water to be treated reached 100 mg / L. Further, as a comparative example, an operation in which the initial concentration of methanol was 300 mg / L and methanol was added 300 mg / L after 24 hours was also performed.

図８は実験結果を示すグラフである。本発明方法ではＴ−Ｎ濃度が初期の３０００ｍｇ／Ｌから２日目には約４００ｍｇ／Ｌにまで低下し、Ｔ−Ｎ除去率８７％を示した。一方、比較例は２日目におけるＴ−Ｎ除去率が４０％程度であった。本発明方法では初期濃度が３００ｍｇ／Ｌのメタノールは運転開始後の早い段階（数時間以内）で還元反応における水素供与体として消費され、以降は自動制御によるメタノール濃度が９０〜１００ｍｇ／Ｌを維持した運転を行ったため、水素供与体としてメタノールが常時、過不足なく補給されて高いＴ−Ｎ窒素除去率を達成したものと考えられる。一方、比較例では初期濃度が３００ｍｇ／Ｌのメタノールは運転開始後の早い段階（数時間以内）で還元反応における水素供与体として消費され、以降のメタノール濃度制御が不適正であったために、水素供与体の不足によって還元反応が進まず、Ｔ−Ｎ除去率の低下を招いたものと考えられる。   FIG. 8 is a graph showing experimental results. In the method of the present invention, the TN concentration decreased from the initial 3000 mg / L to about 400 mg / L on the second day, indicating a TN removal rate of 87%. On the other hand, in the comparative example, the TN removal rate on the second day was about 40%. In the method of the present invention, methanol having an initial concentration of 300 mg / L is consumed as a hydrogen donor in the reduction reaction at an early stage (within several hours) after the start of operation. Thereafter, the methanol concentration by automatic control is maintained at 90 to 100 mg / L. Therefore, it is considered that methanol as a hydrogen donor was always replenished without excess and deficiency to achieve a high TN nitrogen removal rate. On the other hand, in the comparative example, methanol having an initial concentration of 300 mg / L was consumed as a hydrogen donor in the reduction reaction at an early stage (within several hours) after the start of operation, and the subsequent methanol concentration control was inappropriate. It is considered that the reduction reaction did not proceed due to a shortage of donors, leading to a decrease in the TN removal rate.

集積培養した嫌気性アンモニア酸化細菌を用いて各種アンモニア濃度における脱窒速度を測定したデータである。It is the data which measured the denitrification speed | rate in various ammonia concentration using the anaerobic ammonia oxidation bacteria which carried out the accumulation | cultivation culture. 各種濃度のメタノールを添加した場合における嫌気性アンモニア酸化反応の脱窒活性比を測定したデータである。It is the data which measured the denitrification activity ratio of the anaerobic ammonia oxidation reaction at the time of adding methanol of various density | concentrations. 模擬廃水の回分処理結果を示すデータである。It is data which shows the batch processing result of simulated wastewater. 本発明に係る窒素含有水の回分処理方法の第１実施形態を示す系統図である。It is a systematic diagram showing a first embodiment of a batch treatment method for nitrogen-containing water according to the present invention. メタノール濃度の管理例を示したモデル図である。It is the model figure which showed the example of management of methanol concentration. 本発明に係る窒素含有水の回分処理方法の第２実施形態を示す系統図である。It is a systematic diagram which shows 2nd Embodiment of the batch processing method of the nitrogen-containing water which concerns on this invention. 実施例１の実験結果を示すグラフである。4 is a graph showing experimental results of Example 1. 実施例２の実験結果を示すグラフである。6 is a graph showing experimental results of Example 2.

符号の説明Explanation of symbols

１０………反応槽、１２,１２Ａ………被処理水、１２Ｂ………硝化液、１４………担体、１６………排出口、１８………攪拌機、２０………スクリーン、２２………排出弁、２４………排出管、２６………窒素濃度計、２８………メタノール濃度計、３０………制御器、３２………メタノール添加手段、３４………電磁弁、４０………硝化槽。 DESCRIPTION OF SYMBOLS 10 ......... Reaction tank, 12,12A ......... Water to be treated, 12B ......... Nitrification liquid, 14 ......... Carrier, 16 ......... Discharge port, 18 ...... Stirrer, 20 ...... Screen, 22 ......... Discharge valve, 24 ......... Exhaust pipe, 26 ......... Nitrogen concentration meter, 28 ......... Methanol concentration meter, 30 ......... Controller, 32 ......... Methanol addition means, 34 ......... Solenoid valve , 40 ... …… Nitrification tank.

Claims (3)

嫌気性アンモニア酸化細菌と従属栄養性の硝酸還元菌とを共存させた反応槽内にアンモニアと硝酸を含有する被処理水を張り込み、該被処理水を前記嫌気性アンモニア酸化細菌及び硝酸還元菌と接触させることによって回分式に脱窒処理する窒素含有水の回分処理方法において、前記反応槽内における被処理水のメタノール初期濃度が５００ｍｇ／Ｌ以下となる条件でメタノールを初期添加し、前記メタノールを初期添加した後に、前記反応槽内の被処理水のメタノール濃度が１００ｍｇ／Ｌ以下で、かつＣ／Ｎ比が０．１以上を維持するように前記メタノールを随時に添加することを特徴とする窒素含有水の回分処理方法。 A treated water containing ammonia and nitric acid is placed in a reaction tank in which anaerobic ammonia oxidizing bacteria and heterotrophic nitrate reducing bacteria coexist, and the treated water is mixed with the anaerobic ammonia oxidizing bacteria and nitrate reducing bacteria. in denitrified nitrogen-containing water of batch processing method for batchwise by contacting the methanol initial concentration of the water to be treated in the reaction tank is methanol was added initially at conditions equal to or less than 500 mg / L, the methanol After the initial addition, the methanol is added as needed so that the methanol concentration of the water to be treated in the reaction tank is 100 mg / L or less and the C / N ratio is maintained at 0.1 or more. Batch processing method for nitrogen-containing water. 前記嫌気性アンモニア酸化細菌と従属栄養性の硝酸還元菌を高分子ゲルの内部に包括固定した状態で前記反応槽内に共存させることを特徴とする請求項１に記載の窒素含有水の回分処理方法。 2. The batch treatment of nitrogen-containing water according to claim 1 , wherein the anaerobic ammonia-oxidizing bacteria and heterotrophic nitrate-reducing bacteria coexist in the reaction vessel in a state of being comprehensively fixed inside a polymer gel. Method. 前記反応槽の前段で前記被処理水のアンモニア性窒素と硝酸性窒素の濃度比を調整することを特徴とする請求項１又は２に記載の窒素含有水の回分処理方法。 The batch treatment method for nitrogen-containing water according to claim 1 or 2 , wherein a concentration ratio of ammonia nitrogen and nitrate nitrogen of the water to be treated is adjusted in a front stage of the reaction tank.
JP2006067327A 2006-03-13 2006-03-13 Batch treatment of nitrogen-containing water Expired - Fee Related JP4817057B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2006067327A JP4817057B2 (en) 2006-03-13 2006-03-13 Batch treatment of nitrogen-containing water

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2006067327A JP4817057B2 (en) 2006-03-13 2006-03-13 Batch treatment of nitrogen-containing water

Publications (2)

Publication Number Publication Date
JP2007237145A JP2007237145A (en) 2007-09-20
JP4817057B2 true JP4817057B2 (en) 2011-11-16

Family

ID=38583209

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2006067327A Expired - Fee Related JP4817057B2 (en) 2006-03-13 2006-03-13 Batch treatment of nitrogen-containing water

Country Status (1)

Country Link
JP (1) JP4817057B2 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4817056B2 (en) * 2006-03-13 2011-11-16 株式会社日立プラントテクノロジー Method and apparatus for treating nitrogen-containing water
JP2008023485A (en) * 2006-07-24 2008-02-07 Japan Organo Co Ltd Biological denitrification method and apparatus therefor
KR101023479B1 (en) 2008-07-15 2011-03-28 (주)태화종합기술공사 A aerobic deammonification method of SBR type sewage, waste, livestock waste water treatment plant by use of micro sand bio mass, chemical and apparatus therof
JP6210883B2 (en) * 2014-01-09 2017-10-11 株式会社日立製作所 Operation method of waste water treatment equipment
JP6435108B2 (en) * 2014-03-26 2018-12-05 パナソニック株式会社 Denitrification device and method of operating denitrification device

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4867099B2 (en) * 2001-07-30 2012-02-01 栗田工業株式会社 Biological denitrification method
JP2003053385A (en) * 2001-08-09 2003-02-25 Kurita Water Ind Ltd Biological denitrification equipment
JP4284700B2 (en) * 2004-03-25 2009-06-24 株式会社日立プラントテクノロジー Nitrogen removal method and apparatus
JP4042718B2 (en) * 2004-05-06 2008-02-06 株式会社日立プラントテクノロジー Anaerobic ammonia oxidation method and apparatus
JP4817056B2 (en) * 2006-03-13 2011-11-16 株式会社日立プラントテクノロジー Method and apparatus for treating nitrogen-containing water

Also Published As

Publication number Publication date
JP2007237145A (en) 2007-09-20

Similar Documents

Publication Publication Date Title
Terada et al. Nitrogen removal characteristics and biofilm analysis of a membrane-aerated biofilm reactor applicable to high-strength nitrogenous wastewater treatment
KR101377107B1 (en) Method and apparatus for treating ammonia-containing solution
JP5324269B2 (en) Waste water treatment method and waste water treatment apparatus
CN101844830B (en) Wastewater treatment method
US20140374344A1 (en) Method for treating wastewater containing ammonia nitrogen
JP5098183B2 (en) Waste water treatment method and apparatus
JP4626884B2 (en) Culture method and apparatus for anaerobic ammonia oxidizing bacteria
JP2001170684A (en) Ammonia-containing waste water treatment method and device therefor
Zhang et al. Integration of nitrification and denitrifying dephosphatation in airlift loop sequencing batch biofilm reactor
JP4817057B2 (en) Batch treatment of nitrogen-containing water
JP4600817B2 (en) Method for treating ammonia-containing water
JP4915036B2 (en) Denitrification method and denitrification apparatus
JP2003285096A (en) Simultaneous denitrification and dephosphorization type treatment method for wastewater
JP2014097478A (en) Effluent treatment method and effluent treatment apparatus
Garrido et al. Nitrous oxide production by nitrifying biofilms in a biofilm airlift suspension reactor
JP4817056B2 (en) Method and apparatus for treating nitrogen-containing water
JP4835906B2 (en) Treatment equipment for ammonia-containing liquid
JP2012035215A (en) Wastewater treatment apparatus and waste water treatment method
JP4600816B2 (en) Method for treating ammonia-containing water
JP3278841B2 (en) Nitrification and denitrification of wastewater
JPH09299988A (en) Nitrificating and denitrificating method and device therefor
JP5240465B2 (en) Storage system and storage method for anaerobic microorganism-immobilized carrier
JP4618420B2 (en) Method for oxidizing nitrous acid-containing liquid
JP3858271B2 (en) Wastewater treatment method and apparatus
JP5126691B2 (en) Wastewater treatment method

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20080318

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20090731

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20110526

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20110621

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20110805

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20110818

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20140909

Year of fee payment: 3

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313111

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

LAPS Cancellation because of no payment of annual fees