JPH07265877A - Treatment of ammonia-containing waste water - Google Patents

Treatment of ammonia-containing waste water

Info

Publication number
JPH07265877A
JPH07265877A JP8596394A JP8596394A JPH07265877A JP H07265877 A JPH07265877 A JP H07265877A JP 8596394 A JP8596394 A JP 8596394A JP 8596394 A JP8596394 A JP 8596394A JP H07265877 A JPH07265877 A JP H07265877A
Authority
JP
Japan
Prior art keywords
ammonia
waste water
water
nitrite
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.)
Pending
Application number
JP8596394A
Other languages
Japanese (ja)
Inventor
Yoshiro Yuasa
芳郎 湯浅
Susumu Izumitani
進 泉谷
Shuichi Sakamoto
秀一 坂本
Yasuhiko Takabayashi
泰彦 高林
Toshiji Nakahara
敏次 中原
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.)
Kansai Electric Power Co Inc
Kurita Water Industries Ltd
Original Assignee
Kansai Electric Power Co Inc
Kurita Water Industries 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 Kansai Electric Power Co Inc, Kurita Water Industries Ltd filed Critical Kansai Electric Power Co Inc
Priority to JP8596394A priority Critical patent/JPH07265877A/en
Publication of JPH07265877A publication Critical patent/JPH07265877A/en
Pending legal-status Critical Current

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  • Treatment Of Water By Oxidation Or Reduction (AREA)
  • Removal Of Specific Substances (AREA)

Abstract

PURPOSE:To enhance the efficiency in the catalytic decomposition of waste water by adding a nitrite to the ammonia-contg. waste water, bringing the waste water into contact with a metal-carrying catalyst under heating, separating and removing the generated gaseous nitrogen and then bringing the waste water into contact with a metal-carrying catalyst. CONSTITUTION:Plural fixed-bed catalystic reactors 5, 7 and 9 to treat ammonia- contg. waste water are arranged in series, nitrous acid or a nitrite is added to the waste water introduced into a raw water tank 1, and then sulfuric acid or sodium hydroxide is admixed and agitated to regulate the waste water to about pH6-7. The regulated waste water is delivered by a pump 2, preheated by a heat exchanger 3, then heated to about 130-180 deg.C by a heater 4 and introduced into a first reactor 5. The gaseous nitrogen generated by the catalytic decomposition of ammonia with a metal-carrying catalyst is extracted from a valve 6, and then treated water is sent to a second reactor 7. The generated gaseous nitrogen is extracted from a valve 8, the treated water is sent to a third reactor 9 and treated in the same way to obtain the desired treated water quality.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、アンモニア含有排水中
のアンモニアの分解方法の改良に関するものである。さ
らに詳しくは、本発明は、触媒を用いて排水中のアンモ
ニアを分解除去する方法において、反応の進行に伴って
発生するガスを抜き取ることにより触媒と被処理水の接
触状態を向上させた、効率のよいアンモニアの分解方法
に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved method for decomposing ammonia in wastewater containing ammonia. More specifically, the present invention is a method for decomposing and removing ammonia in wastewater using a catalyst, in which the contact state of the catalyst and the water to be treated is improved by extracting the gas generated with the progress of the reaction. The present invention relates to a good ammonia decomposition method.

【0002】[0002]

【従来の技術】火力、原子力発電用ボイラの復水脱塩装
置の再生排水や、肥料工場排水などには、アンモニアが
かなりの量含まれており、このアンモニアの除去方法と
して、例えば、生物学的硝化脱窒素法、アンモニアスト
リッピング法、塩素酸化法、接触分解法などが知られて
いる。前記のアンモニアの除去方法の中で、生物学的硝
化脱窒素法は、硝化細菌によりアンモニアを亜硝酸性又
は硝酸性窒素に酸化したのち、脱窒素細菌により窒素ガ
スに還元する方法である。しかしながら、この方法は、
微生物反応であるため、種々の変動要因に対して分解活
性が不安定である上、広い設置面積が必要であり、かつ
汚泥の後処理が必要であるなどの欠点を有している。ま
た、アンモニアストリッピング法は、アルカリ性条件下
に大量の空気と接触させて、アンモニアを大気中に放散
させる方法である。しかしながら、この方法はアルカリ
コストが高く、かつ放散させたアンモニアを再度吸着濃
縮する必要があり、経済的でない。一方、塩素酸化法
は、塩素添加により、アンモニウムイオンをクロラミン
を経由して窒素ガスに酸化する方法である。この方法は
塩素添加量がアンモニアの10倍程度必要であり、アン
モニア濃度の高い排水処理には不向きである上、残留塩
素の後処理が必要である。これらの方法に対し、接触分
解法は、装置の設置面積が小さい、運転管理が容易であ
る、汚泥や残留塩素といった後処理を必要とする物質が
生成しない、などの優れた特徴を有する処理方法であ
り、例えば、特開平4−293553号公報には、アン
モニアを含む排水に酸化剤として亜硝酸又は亜硝酸塩を
添加したのち、触媒の存在下で加熱することにより、ア
ンモニアを酸化分解する方法が提案されている。この場
合、被処理水中のアンモニア性窒素は次の反応式にした
がって分解され窒素ガスが発生する。 NH4 ++NO2 - → NH4NO2 → N2+2H2O 通常、アンモニアの接触分解反応は固定床式触媒反応装
置で行われるが、ここで発生する窒素ガスのために被処
理水と触媒の接触が妨げられ、上記の反応が円滑に進行
しないという問題があり、被処理水と触媒の接触を常に
良好に保つことのできる処理方法が求められてきた。
2. Description of the Related Art A considerable amount of ammonia is contained in reclaimed wastewater of a condensate desalination unit of a boiler for thermal power and nuclear power generation, wastewater of a fertilizer factory, and the like. The known nitrification denitrification method, ammonia stripping method, chlorine oxidation method, catalytic cracking method and the like are known. Among the above-mentioned methods for removing ammonia, the biological nitrifying and denitrifying method is a method in which nitrifying bacteria oxidize ammonia to nitrite or nitrate nitrogen and then denitrifying bacteria reduce it to nitrogen gas. However, this method
Since it is a microbial reaction, its decomposition activity is unstable with respect to various fluctuation factors, and it requires a large installation area and requires post-treatment of sludge. Further, the ammonia stripping method is a method of contacting with a large amount of air under alkaline conditions to diffuse ammonia into the atmosphere. However, this method is not economical because it requires a high alkali cost and needs to adsorb and concentrate the diffused ammonia again. On the other hand, the chlorine oxidation method is a method of oxidizing ammonium ions into nitrogen gas via chloramine by adding chlorine. This method requires approximately 10 times the amount of chlorine added to ammonia, and is not suitable for treating wastewater having a high ammonia concentration, and requires post-treatment of residual chlorine. In contrast to these methods, the catalytic cracking method is a treatment method having excellent characteristics such as a small installation area of the device, easy operation management, and generation of substances requiring post-treatment such as sludge and residual chlorine. Thus, for example, JP-A-4-293553 discloses a method of oxidatively decomposing ammonia by adding nitrous acid or nitrite as an oxidant to waste water containing ammonia and then heating the catalyst in the presence of a catalyst. Proposed. In this case, ammoniacal nitrogen in the water to be treated is decomposed according to the following reaction formula to generate nitrogen gas. NH 4 + + NO 2 - → NH 4 NO 2 → N 2 + 2H 2 O usually catalytic cracking reaction of ammonia is carried out in a fixed bed catalytic reactor, the water to be treated and a catalyst for the nitrogen gas generated here However, there is a problem that the above reaction does not proceed smoothly, and there has been a demand for a treatment method capable of always maintaining good contact between the water to be treated and the catalyst.

【0003】[0003]

【発明が解決しようとする課題】本発明は、酸化剤とし
て亜硝酸又は亜硝酸塩を用いてアンモニアを接触分解す
る従来のアンモニアの除去方法が有するこのような問題
を解決し、アンモニアの分解により窒素ガスが発生して
も、固定床式触媒反応装置中の粒状固体触媒と被処理水
の接触状態が阻害されることなく、良好な処理効率を維
持することのできるアンモニアを含む排水の処理方法を
提供することを目的としてなされたものである。
DISCLOSURE OF THE INVENTION The present invention solves such a problem of the conventional method for removing ammonia by catalytically decomposing ammonia by using nitrous acid or nitrite as an oxidizing agent, and by decomposing ammonia, nitrogen is decomposed. Even if gas is generated, a method for treating wastewater containing ammonia that can maintain good treatment efficiency without disturbing the contact state of the granular solid catalyst and the water to be treated in the fixed bed catalytic reactor is provided. It was made for the purpose of providing.

【0004】[0004]

【課題を解決するための手段】本発明者らは、発生ガス
の影響を軽減する方法を鋭意研究した結果、処理途中で
発生した窒素ガスを系外に抜き取ることによって触媒と
被処理水との接触状態を良好に保ち処理効果を向上させ
得ることを見いだし、この知見に基づいて本発明を完成
するに至った。すなわち、本発明は、 (1)アンモニア含有排水に亜硝酸塩を添加し、加熱条
件下に金属担持触媒と接触させ、次いで発生した窒素ガ
スを分離除去したのち、さらに加熱条件下に金属担持触
媒と接触させてアンモニアを分解することを特徴とする
アンモニア含有排水の処理方法を提供するものである。
Means for Solving the Problems As a result of earnest studies on a method for reducing the influence of generated gas, the inventors of the present invention separated nitrogen gas generated during processing from the system to separate the catalyst and the water to be treated. It was found that the contact state can be kept good and the treatment effect can be improved, and the present invention has been completed based on this finding. That is, according to the present invention, (1) nitrite is added to ammonia-containing wastewater, the nitrite is brought into contact with a metal-supported catalyst under heating conditions, the generated nitrogen gas is separated and removed, and then the metal-supported catalyst is further heated under heating conditions. Disclosed is a method for treating ammonia-containing wastewater, which comprises contacting and decomposing ammonia.

【0005】以下、本発明を詳細に説明する。本発明方
法において、排水中に含まれるアンモニア性窒素1モル
当たり0.5〜2モル、好ましくは0.9〜1.1モルの
亜硝酸又は亜硝酸塩を添加する。亜硝酸塩としては、亜
硝酸ナトリウム、亜硝酸カリウムのような亜硝酸のアル
カリ金属塩を好適に用いることができる。亜硝酸又は亜
硝酸塩の使用量が、アンモニア性窒素1モル当たり0.
5モル未満であれば、排水中のアンモニアを十分除去す
ることができない。また、亜硝酸又は亜硝酸塩の使用量
が、アンモニア性窒素1モル当たり2モルを超えると、
アンモニアを除去した後の排水中に亜硝酸イオンが確実
に残るようになるので好ましくない。本発明方法におい
て、亜硝酸又は亜硝酸塩を添加した排水は、酸又はアル
カリを加えることによりpHを調整する。pH調整に用いる
酸としては、例えば、硫酸又は塩酸を好適に使用するこ
とができる。pH調整に用いるアルカリとしては、例え
ば、水酸化ナトリウム、水酸化カリウムのようなアルカ
リ金属の水酸化物、炭酸ナトリウム、炭酸カリウムのよ
うなアルカリ金属の炭酸塩を好適に使用することができ
る。アンモニアの接触分解を行うためには、被処理水の
pHは6〜7であることが好ましい。
The present invention will be described in detail below. In the method of the present invention, 0.5 to 2 mol, preferably 0.9 to 1.1 mol of nitrous acid or nitrite is added per 1 mol of ammonia nitrogen contained in the waste water. As the nitrite, an alkali metal salt of nitrite such as sodium nitrite and potassium nitrite can be preferably used. The amount of nitrous acid or nitrite used is 0.1 per mol of ammoniacal nitrogen.
If it is less than 5 mol, ammonia in the waste water cannot be sufficiently removed. When the amount of nitrite or nitrite used exceeds 2 mol per mol of ammoniacal nitrogen,
Nitrite ions are surely left in the waste water after removing the ammonia, which is not preferable. In the method of the present invention, the pH of the wastewater to which nitrous acid or nitrite has been added is adjusted by adding acid or alkali. As the acid used for pH adjustment, for example, sulfuric acid or hydrochloric acid can be preferably used. As the alkali used for pH adjustment, for example, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and alkali metal carbonates such as sodium carbonate and potassium carbonate can be preferably used. In order to carry out catalytic decomposition of ammonia,
The pH is preferably 6-7.

【0006】本発明方法において、亜硝酸又は亜硝酸塩
を添加し、pHを調整した排水は次いで金属担持触媒を充
填した固定床式触媒反応装置へ送られる。この反応装置
で、アンモニアは亜硝酸塩と反応して無害な窒素ガスと
なる。金属触媒としては、白金、パラジウム及びルテニ
ウムなどを用いることができる。担体としては、α−ア
ルミナ、γ−アルミナなどのアルミナ類、シリカ、シリ
カアルミナ系、チタニア系などの金属酸化物などを用い
ることができる。金属の担持量は0.1〜10重量%で
あることが好ましい。金属の担持量が0.1重量%未満
であるとアンモニアの分解が不十分となりやすい。金属
の担持量が10重量%を超えても、担持量の増加に見合
ってアンモニアの分解がより容易になることはない。固
定床式触媒反応装置の温度は100〜300℃、より好
ましくは130〜180℃に保って反応を行う。反応装
置の温度が100℃未満であれば、接触時間を長くして
もアンモニアの分解が不十分となりやすく、反応装置の
温度が300℃を超えると、反応装置に高い耐圧性が必
要になる上に、いたずらにエネルギーを浪費するばかり
で、アンモニアの分解効率は向上しないので好ましくな
い。粒状固体触媒を用いた固定床式触媒反応装置でアン
モニアの分解処理を行う場合には、処理過程で発生した
窒素ガスが触媒と被処理水との接触効率を低下させる。
例えば、窒素として2,500ppmのアンモニアを含む水
に亜硝酸塩を理論当量だけ添加してアンモニアを除去す
る場合、被処理水1リットルから標準状態で約4リット
ルの窒素ガスが発生し、反応装置の出口付近では加圧条
件下でも被処理水の占める容積よりも窒素ガスの占める
容積の方が大きいような状態になる。このような状態で
は発生ガスによる接触反応の阻害が無視できない。
In the method of the present invention, the pH-adjusted wastewater to which nitrous acid or nitrite is added is then sent to a fixed bed type catalytic reactor filled with a metal-supported catalyst. In this reactor, ammonia reacts with nitrite to form harmless nitrogen gas. As the metal catalyst, platinum, palladium, ruthenium, or the like can be used. As the carrier, alumina such as α-alumina and γ-alumina, silica, silica-alumina-based, titania-based metal oxide and the like can be used. The amount of metal supported is preferably 0.1 to 10% by weight. When the amount of metal supported is less than 0.1% by weight, the decomposition of ammonia tends to be insufficient. Even if the amount of metal supported exceeds 10% by weight, the decomposition of ammonia does not become easier in proportion to the increase in the amount supported. The temperature of the fixed bed type catalytic reactor is maintained at 100 to 300 ° C, more preferably 130 to 180 ° C, to carry out the reaction. If the temperature of the reactor is less than 100 ° C, decomposition of ammonia tends to be insufficient even if the contact time is lengthened, and if the temperature of the reactor exceeds 300 ° C, the reactor requires high pressure resistance. In addition, it is not preferable because it merely wastes energy unnecessarily and does not improve the decomposition efficiency of ammonia. When decomposing ammonia with a fixed bed catalytic reactor using a granular solid catalyst, the nitrogen gas generated in the treatment process reduces the contact efficiency between the catalyst and the water to be treated.
For example, when a theoretical equivalent amount of nitrite is added to water containing 2500 ppm of ammonia as nitrogen to remove ammonia, about 4 liters of nitrogen gas is generated from 1 liter of treated water in a standard state, and In the vicinity of the outlet, the volume occupied by nitrogen gas is larger than the volume occupied by the water to be treated even under pressurized conditions. In such a state, the inhibition of the contact reaction due to the generated gas cannot be ignored.

【0007】次に、本発明方法実施の一態様を図面によ
り説明する。図1は、本発明方法を実施するための装置
の一例のフローシートである。アンモニアを含む排水を
処理する固定床式触媒反応装置は複数個が直列に配置さ
れ、各反応装置の間にガス抜きのためのバルブが設けら
れる。原水タンク1に導入された排水に、亜硝酸又は亜
硝酸ナトリウムのような亜硝酸塩を添加したのち、硫酸
又は水酸化ナトリウムなどを加え撹拌することによりpH
6〜7に調整する。亜硝酸又は亜硝酸塩を添加しpH調整
を終わった排水をポンプ2により送り出し、熱交換器3
で予熱したのちヒーター4で130〜180℃に加熱し
て第1の固定床式触媒反応装置5へ導く。アンモニアの
接触分解により発生した窒素ガスは、第1の反応装置の
出口に設けたバルブ6から抜き取り、被処理水を第2の
固定床式触媒反応装置7に送液する。窒素ガスを分離し
たのち同じ固定床式触媒反応装置に返送することは処理
水質の悪化を招くため好ましくない。第2の固定床式触
媒反応装置7で発生した窒素ガスは、第2の反応装置の
出口に設けたバルブ8から抜き取り、被処理水を次の固
定床式触媒反応装置に送液する。目的とする処理水質が
得られるまで、必要に応じて同様な操作をくり返すが、
通常は2基の固定床式触媒反応装置で満足すべき結果が
得られることが多い。最後の固定床式触媒反応装置9か
ら送り出された被処理水は、熱交換器3で余熱を利用し
たのち、調圧バルブ10を経由して貯槽へ送り自然放冷
する。本発明方法において、アンモニアを除去した排水
は、必要に応じ公知の方法によりpHを調整して放流す
る。本発明方法において、アンモニアの分解のために必
要な全接触時間は、通常は3〜100分間、多くの場合
は12〜30分間程度である。通液速度は通常0.5〜
20hr-1、好ましくは2〜8hr-1の範囲が有利である。
本発明方法において、処理対象となるアンモニア含有水
は、アンモニアを窒素として10〜5000mg/リット
ルの範囲で含有するものが適当であり、このようなアン
モニア含有水としては、発電用ボイラの復水脱塩装置の
再生排水や肥料工場の排水などが挙げられる。
Next, one embodiment of the method of the present invention will be described with reference to the drawings. FIG. 1 is a flow sheet of an example of an apparatus for carrying out the method of the present invention. A plurality of fixed bed catalytic reactors for treating wastewater containing ammonia are arranged in series, and a valve for venting gas is provided between the reactors. After adding nitrite such as nitrous acid or sodium nitrite to the wastewater introduced into the raw water tank 1, add sulfuric acid or sodium hydroxide, etc. and stir the pH.
Adjust to 6-7. The effluent after pH adjustment by adding nitrous acid or nitrite is sent out by the pump 2 and the heat exchanger 3
After being preheated by (3), it is heated to 130 to 180 ° C. by the heater 4 and introduced to the first fixed bed type catalytic reactor 5. Nitrogen gas generated by the catalytic decomposition of ammonia is extracted from the valve 6 provided at the outlet of the first reactor, and the water to be treated is sent to the second fixed bed catalytic reactor 7. It is not preferable to separate the nitrogen gas and then return it to the same fixed bed type catalytic reactor, since this will deteriorate the quality of treated water. The nitrogen gas generated in the second fixed-bed catalytic reaction device 7 is extracted from the valve 8 provided at the outlet of the second reaction device, and the water to be treated is sent to the next fixed-bed catalytic reaction device. Repeat the same operation as necessary until the desired treated water quality is obtained,
In general, two fixed bed catalytic reactors often provide satisfactory results. The water to be treated sent out from the final fixed-bed catalytic reaction device 9 utilizes residual heat in the heat exchanger 3, and then is sent to the storage tank via the pressure regulating valve 10 to be naturally cooled. In the method of the present invention, the pH of the wastewater from which ammonia has been removed is adjusted by a known method, if necessary, and then discharged. In the method of the present invention, the total contact time required for the decomposition of ammonia is usually 3 to 100 minutes, and in most cases about 12 to 30 minutes. Liquid passing rate is usually 0.5-
20 hr -1, preferably advantageous range 2~8hr -1.
In the method of the present invention, it is appropriate that the ammonia-containing water to be treated contains ammonia as nitrogen in the range of 10 to 5000 mg / liter. Examples include recycled wastewater from salt equipment and wastewater from fertilizer plants.

【0008】[0008]

【実施例】次に、実施例により本発明をさらに詳細に説
明するが、本発明はこれによってなんら限定されるもの
ではない。 実施例1 図2は、本実施例に用いた装置のフローシートである。
1リットル中にアンモニア性窒素を1000mg含有する
排水を原水タンク11に入れ、水酸化ナトリウムを加え
てpHを5.8に調整後、アンモニアと当量の亜硝酸ナト
リウム、すなわち排水1リットル当たり4.93gの亜
硝酸ナトリウムを添加して均一に混合した。この時のpH
は6.5であった。この排水をポンプ12により、0.5
重量%白金担持/TiO2(粒径3.0mm)の触媒40ml
を充填し、140℃の油浴中に浸漬した第1触媒反応槽
13に240ml/hrの流速で送液した。被処理水は冷却
槽14で冷却後、貯留槽16で気液分離した、さらに第
1触媒反応槽13と全く同じ条件に設定した第2触媒反
応槽18へ、ポンプ17により240ml/hrの流速で送
液した。第2触媒反応槽18での接触分解を終了した被
処理水は冷却槽19で冷却し、バルブ20より取り出し
た。処理水中のアンモニア性窒素の濃度は43mg/リッ
トル、亜硝酸性窒素の濃度は37mg/リットルであっ
た。原水のアンモニア性窒素の濃度に対する除去率は全
窒素換算で92%となる。 比較例1 実施例1の装置の第1触媒反応槽の後の冷却槽と気液分
離のための貯留槽を省略し、第1触媒反応槽と第2触媒
反応槽を直接連絡した他は実施例1と全く同じ条件でア
ンモニア性窒素を含有する排水を通液処理した。処理水
中のアンモニア性窒素の濃度は115mg/リットル、亜
硝酸性窒素の濃度は103mg/リットルであった。原水
のアンモニア性窒素の濃度に対する除去率は全窒素換算
で78%となり、第1触媒反応槽の後で発生した窒素ガ
スの分離除去を行わないと窒素の除去率が著しく低下す
ることが分かる。
EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these. Example 1 FIG. 2 is a flow sheet of the apparatus used in this example.
Waste water containing 1000 mg of ammonia nitrogen in 1 liter was put in the raw water tank 11 and sodium hydroxide was added to adjust the pH to 5.8, and then sodium nitrite equivalent to ammonia, that is, 4.93 g per liter of waste water. Of sodium nitrite was added and mixed uniformly. PH at this time
Was 6.5. This drainage is pumped to 0.5 by the pump 12.
40 ml of wt% platinum supported / TiO 2 (particle size 3.0 mm) catalyst
Was charged and was sent to the first catalytic reaction tank 13 immersed in an oil bath at 140 ° C. at a flow rate of 240 ml / hr. After the water to be treated is cooled in the cooling tank 14, it is separated into gas and liquid in the storage tank 16, and further, to the second catalytic reaction tank 18 which is set under exactly the same conditions as the first catalytic reaction tank 13, the flow rate of 240 ml / hr is set by the pump 17. It was sent at. The water to be treated which had undergone the catalytic decomposition in the second catalytic reaction tank 18 was cooled in the cooling tank 19 and taken out from the valve 20. The concentration of ammonia nitrogen in the treated water was 43 mg / liter, and the concentration of nitrite nitrogen was 37 mg / liter. The removal rate with respect to the concentration of ammonia nitrogen in the raw water is 92% in terms of total nitrogen. Comparative Example 1 The procedure of Example 1 was repeated except that the cooling tank after the first catalytic reaction tank and the storage tank for gas-liquid separation were omitted, and the first catalytic reaction tank and the second catalytic reaction tank were directly connected. Under the same conditions as in Example 1, the drainage containing ammoniacal nitrogen was passed through. The concentration of ammonia nitrogen in the treated water was 115 mg / liter, and the concentration of nitrite nitrogen was 103 mg / liter. The removal rate with respect to the concentration of ammonia nitrogen in the raw water was 78% in terms of total nitrogen, and it can be seen that the removal rate of nitrogen is significantly reduced unless the nitrogen gas generated after the first catalytic reaction tank is separated and removed.

【0009】[0009]

【発明の効果】固定床式触媒反応装置内で発生した窒素
ガスを分離除去することにより、被処理水と触媒の接触
阻害を防止し、排水中のアンモニアの接触分解の処理効
率を向上する。
Industrial Applicability By separating and removing the nitrogen gas generated in the fixed bed type catalytic reactor, the contact inhibition of the water to be treated and the catalyst is prevented, and the treatment efficiency of the catalytic decomposition of ammonia in the waste water is improved.

【図面の簡単な説明】[Brief description of drawings]

【図1】図1は、本発明方法を実施するための装置の一
例のフローシートである。
FIG. 1 is a flow sheet of an example of an apparatus for carrying out the method of the present invention.

【図2】図2は、実施例に用いた装置のフローシートで
ある。
FIG. 2 is a flow sheet of the apparatus used in the examples.

【符号の説明】[Explanation of symbols]

1 原水タンク 2 ポンプ 3 熱交換器 4 ヒーター 5 第1の固定床式触媒反応装置 6 バルブ 7 第2の固定床式触媒反応装置 8 バルブ 9 最後の固定床式触媒反応装置 10 調圧バルブ 11 原水タンク 12 ポンプ 13 第1触媒反応槽 14 冷却槽 15 バルブ 16 貯留槽 17 ポンプ 18 第2触媒反応槽 19 冷却槽 20 バルブ 1 Raw Water Tank 2 Pump 3 Heat Exchanger 4 Heater 5 First Fixed Bed Catalytic Reactor 6 Valve 7 Second Fixed Bed Catalytic Reactor 8 Valve 9 Last Fixed Bed Catalytic Reactor 10 Pressure Control Valve 11 Raw Water Tank 12 Pump 13 First catalytic reaction tank 14 Cooling tank 15 Valve 16 Storage tank 17 Pump 18 Second catalytic reaction tank 19 Cooling tank 20 Valve

───────────────────────────────────────────────────── フロントページの続き (72)発明者 坂本 秀一 東京都新宿区西新宿3丁目4番7号 栗田 工業株式会社内 (72)発明者 高林 泰彦 東京都新宿区西新宿3丁目4番7号 栗田 工業株式会社内 (72)発明者 中原 敏次 東京都新宿区西新宿3丁目4番7号 栗田 工業株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuichi Sakamoto 3-4-7 Nishishinjuku, Shinjuku-ku, Tokyo Kurita Industry Co., Ltd. (72) Inventor Yasuhiko Takabayashi 3-4-7 Nishishinjuku, Shinjuku-ku, Tokyo Kurita Industry Co., Ltd. (72) Inventor Toshiji Nakahara 3-4-7 Nishishinjuku, Shinjuku-ku, Tokyo Kurita Industry Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】アンモニア含有排水に亜硝酸塩を添加し、
加熱条件下に金属担持触媒と接触させ、次いで発生した
窒素ガスを分離除去したのち、さらに加熱条件下に金属
担持触媒と接触させてアンモニアを分解することを特徴
とするアンモニア含有排水の処理方法。
1. A nitrite is added to wastewater containing ammonia,
A method for treating wastewater containing ammonia, which comprises contacting with a metal-supported catalyst under heating conditions, separating and removing generated nitrogen gas, and then contacting with the metal-supported catalyst under heating conditions to decompose ammonia.
JP8596394A 1994-03-31 1994-03-31 Treatment of ammonia-containing waste water Pending JPH07265877A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP8596394A JPH07265877A (en) 1994-03-31 1994-03-31 Treatment of ammonia-containing waste water

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8596394A JPH07265877A (en) 1994-03-31 1994-03-31 Treatment of ammonia-containing waste water

Publications (1)

Publication Number Publication Date
JPH07265877A true JPH07265877A (en) 1995-10-17

Family

ID=13873399

Family Applications (1)

Application Number Title Priority Date Filing Date
JP8596394A Pending JPH07265877A (en) 1994-03-31 1994-03-31 Treatment of ammonia-containing waste water

Country Status (1)

Country Link
JP (1) JPH07265877A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI601687B (en) * 2016-06-23 2017-10-11 亞氨科技股份有限公司 Ammonia decomposition apparatus and method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI601687B (en) * 2016-06-23 2017-10-11 亞氨科技股份有限公司 Ammonia decomposition apparatus and method thereof

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