JP2899719B2 - Treatment method for wastewater containing ammonium nitrate - Google Patents

Treatment method for wastewater containing ammonium nitrate

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Publication number
JP2899719B2
JP2899719B2 JP16083890A JP16083890A JP2899719B2 JP 2899719 B2 JP2899719 B2 JP 2899719B2 JP 16083890 A JP16083890 A JP 16083890A JP 16083890 A JP16083890 A JP 16083890A JP 2899719 B2 JP2899719 B2 JP 2899719B2
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Japan
Prior art keywords
wastewater
added
ammonium nitrate
acid
organic substance
Prior art date
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Expired - Fee Related
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JP16083890A
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Japanese (ja)
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JPH0448988A (en
Inventor
吉明 原田
健一 山崎
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OOSAKA GASU KK
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OOSAKA GASU KK
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Description

【発明の詳細な説明】 産業上の利用分野 本発明は、硝酸アンモニウム含有廃水の処理方法に関
する。
The present invention relates to a method for treating wastewater containing ammonium nitrate.

なお、本明細書において、“NH3−N"とあるのは、
“アンモニア態窒素”を意味し、“NO3−N"とあるの
は、“硝酸態窒素”を意味する。また、“%”とあるの
は、“重量%”を意味する。
In the present specification, “NH 3 —N” refers to
Means "ammonia nitrogen", "NO 3 -N" shall be deemed to be replaced, which means "nitrate nitrogen". Further, “%” means “% by weight”.

従来技術及びその問題点 近年、水質規制の観点から化学的酸素要求物質(COD
成分)のみならず、窒素成分(特にアンモニア態窒素)
の除去も重要な課題となつて来た。本発明者らは、アン
モニア含有廃水の処理方法について長期にわたり種々研
究を重ねた結果、特定の触媒の存在下且つ特定の条件
(温度、圧力、供給酸素量など)で湿式酸化処理を行な
うことにより、操作容易にして実用上の経済性を備えた
アンモニア含有廃水の処理方法を完成した(特公昭56−
42992号、特公昭57−33320号、特公昭57−42391号、特
公昭58−27999号、特公昭59−19757号等)。
Conventional technology and its problems In recent years, chemical oxygen demanding substances (COD
Component) as well as nitrogen components (especially ammonia nitrogen)
Removal has also become an important issue. The present inventors have conducted various studies on a method for treating ammonia-containing wastewater over a long period of time. As a result, the present inventors have conducted a wet oxidation treatment in the presence of a specific catalyst and under specific conditions (temperature, pressure, amount of supplied oxygen, etc.). Completed a method for treating ammonia-containing wastewater that is easy to operate and has practical economic efficiency (Japanese Patent Publication No.
42992, JP-B-57-33320, JP-B-57-42391, JP-B-58-27999, JP-B-59-19757, etc.).

最近、発電業界における原子力発電の比重が増大する
に従つて、ウラン原料の処理及び使用済みウラン燃料の
再処理工程から排出されるNH4NO3含有廃水の処理が重要
な技術的課題となりつつある。本発明者らは、この様な
NH4NO3含有廃水の処理に上記一連のアンモニア含有廃水
の処理技術(以下洗顔技術−Iという)を応用すること
を試みた。この試みにおいて、NH4 +イオンは極めて高い
高率で分解されるものの、N3 -イオンの処理については
必ずしも満足すべき結果が得られない場合もあることが
判明した。これは、上記廃水中のNH4NO3濃度が1%(10
000ppm)から10%(100000ppm)程度にも達する場合が
あることによるものと推測される。
Recently, as the specific gravity of nuclear power generation in the power generation industry increases, the treatment of uranium raw materials and the treatment of NH 4 NO 3 containing wastewater discharged from the reprocessing of spent uranium fuel are becoming important technical issues. . The present inventors have proposed such
NH 4 NO 3 was in the process of waste water containing tried to apply the above-described series of ammonia-containing wastewater treatment technology (hereinafter referred to as face washing techniques -I). In this attempt, it was found that although NH 4 + ions were decomposed at a very high rate, treatment of N 3 - ions did not always give satisfactory results. This is because the concentration of NH 4 NO 3 in the wastewater is 1% (10
000 ppm) to as high as 10% (100,000 ppm).

本発明者らは、さらに研究を進めた結果、先願技術を
実施するに際し、添加する酸素量を減少させることによ
り、NH4NO3含有廃水中のNH4 +イオンのみならずN3 -イオ
ンをも高い効率で分解することに成功した(特開昭61−
222585号参照:以下これに開示された技術を先願発明−
IIという)。
The present inventors have further studied and found that, when implementing the prior application technology, by reducing the amount of oxygen to be added, not only NH 4 + ions but also N 3 ions in the NH 4 NO 3 containing wastewater. Has been successfully decomposed with high efficiency (Japanese Unexamined Patent Publication No.
See No. 222585: The technology disclosed in the following is applied to the prior invention-
II).

しかしながら、NH4NO3含有廃水の処理においては、特
に実用上の観点から、処理効率の改善のみならず、さら
に一層のコスト低下(設備費および運転費の減少)が望
まれている。
However, in the treatment of NH 4 NO 3 -containing wastewater, not only improvement in treatment efficiency but also further cost reduction (reduction of equipment cost and operation cost) is desired from a practical viewpoint.

問題点を解決するための手段 本発明者は、上記の如き現状に鑑みて更に種々研究を
重ねた結果、NH4NO3含有廃水中のアンモニア成分、有機
性物質及び無機性物質を分解するに必要な理論酸素量未
満の酸素の存在下に該NH4NO3含有廃水の湿式熱分解を行
なう先願−IIの方法に代えて、NH4NO3含有廃水に有機物
(COD成分)を加え且つ実質的に酸素の不存在下に同様
の処理を行なう場合にも、NH4 +イオンのみならず、N3 -
イオンをも効率良く分解し得るという予想外の事実を見
出した。
Means for Solving the Problems The present inventor has conducted various studies in view of the current situation as described above, and as a result, has found that ammonia, organic and inorganic substances in NH 4 NO 3 -containing wastewater can be decomposed. An organic substance (COD component) is added to the NH 4 NO 3 -containing wastewater instead of the method of the prior application II in which the wet pyrolysis of the NH 4 NO 3 -containing wastewater is performed in the presence of oxygen less than the required theoretical oxygen amount, and even when substantially performs the same process in the absence of oxygen, not NH 4 + ions only, N 3 -
We have found the unexpected fact that ions can be efficiently decomposed.

さらに、本発明者の引き続く研究によれば、COD成分
とアンモニアとを加えたNH4NO3含有廃水を上記と同様に
して湿式熱分解に供する場合には、分解効率がより一層
改善されることを見出した。
Furthermore, according to the inventor of subsequent research, when subjecting the NH 4 NO 3 containing waste water were added and the COD components and ammonia with the wet thermal decomposition in the same manner as above, the decomposition efficiency is more improved further Was found.

さらにまた、NH4NO3含有廃水は、Na、Kなどのアルカ
リ金属の塩乃至イオンを含有していることがあり、これ
らの塩乃至イオンが、湿式熱分解時に一部NH4 +イオンの
NO3 +イオンへの転換反応の促進作用、当初の廃水中に含
まれていたNO3 +イオン及び生成NO3 +イオンの安定化作用
などを発揮するために、全窒素成分分解率が若干低下す
る場合がある。この様な場合には、COD成分と酸または
処理条件下に酸を生成し得る物質とを加えたNH4NO3含有
廃水を上記と同様にして湿式熱分解に供することによ
り、分解効率がさらに一層向上することを見出した。
Furthermore, the NH 4 NO 3 containing wastewater may contain salts or ions of alkali metals such as Na and K, and these salts or ions may partially form NH 4 + ions during wet pyrolysis.
Promoting action of conversion reaction to NO 3 + ions, in order to exert such stabilizing effect of the initial NO 3 was contained in the waste water + ions and generate NO 3 + ions, total nitrogen component decomposition rate is slightly lower May be. In such a case, the decomposition efficiency is further increased by subjecting the NH 4 NO 3 -containing wastewater containing the COD component and the acid or a substance capable of generating an acid under the treatment conditions to wet pyrolysis in the same manner as described above. It has been found that it is further improved.

即ち、本発明は、下記の4種の廃水処理方法を提供す
るものである。
That is, the present invention provides the following four types of wastewater treatment methods.

0.1<有機物/NO3−N≦0.5(モル比)となる様に有
機物を加えた硝酸アンモニウム含有廃水を貴金属及びそ
の不溶性又は難溶性化合物並びに卑金属からなる群から
選ばれた少なくとも1種を活性成分とする担持触媒の存
在下且つ酸素の実質的な不存在下にpH約1〜11.5、温度
100〜370℃で湿式熱分解することを特徴とする硝酸アン
モニウム含有廃水の処理方法。
An ammonium nitrate-containing wastewater to which an organic substance is added so that 0.1 <organic substance / NO 3 −N ≦ 0.5 (molar ratio) is used as an active ingredient at least one selected from the group consisting of a noble metal and its insoluble or hardly soluble compound and a base metal. PH between about 1 and 11.5 in the presence of a supported catalyst and in the substantial absence of oxygen
A method for treating wastewater containing ammonium nitrate, wherein the wastewater is subjected to wet pyrolysis at 100 to 370 ° C.

0.1<有機物/NO3−N≦0.5(モル比)となる様に有
機物を加え且つ 0.1<NH3−N/NO3−N≦2(モル比)となる様にアンモ
ニアを加えた硝酸アンモニウム含有廃水を貴金属及びそ
の不溶性又は難溶性化合物並びに卑金属からなる群から
選ばれた少なくとも1種を活性成分とする担持触媒の存
在下且つ酸素の実質的な不存在下にpH約1〜11.5、温度
100〜370℃で湿式熱分解することを特徴とする硝酸アン
モニウム含有廃水の処理方法。
0.1 <organics / NO 3 -N ≦ 0.5 (molar ratio) the organics as a plus and 0.1 <NH 3 -N / NO 3 -N ≦ 2 ammonium nitrate-containing waste water by adding ammonia as a (molar ratio) A pH of about 1 to 11.5 in the presence of a supported catalyst containing at least one selected from the group consisting of a noble metal and its insoluble or hardly soluble compound and a base metal and in the substantial absence of oxygen;
A method for treating wastewater containing ammonium nitrate, wherein the wastewater is subjected to wet pyrolysis at 100 to 370 ° C.

0.1<有機物/NO3−N≦0.5(モル比)となる様に有
機物を加え且つ酸及び酸生成物質の少なくとも1種を添
加した硝酸アンモニウム含有廃水を貴金属及びその不溶
性又は難溶性化合物並びに卑金属からなる群から選ばれ
た少なくとも1種を活性成分とする担持触媒の存在下且
つ酸素の実質的な不存在下にpH約1〜11.5、温度100〜3
70℃で湿式熱分解することを特徴とする硝酸アンモニウ
ム含有廃水の処理方法。
An ammonium nitrate-containing wastewater to which an organic substance is added so that 0.1 <organic substance / NO 3 −N ≦ 0.5 (molar ratio) and at least one of an acid and an acid-generating substance is added is composed of a noble metal and its insoluble or hardly soluble compound and a base metal. PH of about 1 to 11.5 and a temperature of 100 to 3 in the presence of a supported catalyst containing at least one selected from the group as an active ingredient and in the substantial absence of oxygen.
A method for treating ammonium nitrate-containing wastewater, comprising performing wet pyrolysis at 70 ° C.

0.1<有機物/NO3−N≦0.5(モル比)となる様に有
機物を加え、 0.1<NH3−N/NO3−N≦2(モル比)となる様にアンモ
ニアを加え且つ酸及び酸生成物質の少なくとも1種を添
加した硝酸アンモニウム含有廃水を貴金属及びその不溶
性又は難溶性化合物並びに卑金属からなる群から選ばれ
た少なくとも1種を活性成分とする担持触媒の存在下且
つ酸素の実質的な不存在下にpH約1〜11.5、温度100〜3
70℃で湿式熱分解することを特徴とする硝酸アンモニウ
ム含有廃水の処理方法。
0.1 <organics / NO 3 -N ≦ 0.5 (molar ratio) and becomes an organic substance as addition, 0.1 <NH 3 -N / NO 3 -N ≦ 2 adding ammonia as a (molar ratio) and acids and acid The ammonium nitrate-containing wastewater to which at least one of the product substances is added is converted into a noble metal and an insoluble or hardly soluble compound and a substantially non-oxygen in the presence of a supported catalyst containing at least one selected from the group consisting of base metals as an active ingredient. PH about 1-11.5 in the presence, temperature 100-3
A method for treating ammonium nitrate-containing wastewater, comprising performing wet pyrolysis at 70 ° C.

なお、本発明において、“酸素の実質的な不存在下
に”なる表現は、処理すべき廃水に積極的に酸素を供給
しないことを意味するものであり、処理すべき廃水中に
少量の酸素が溶存している場合をも包含するものであ
る。
In the present invention, the expression "in the substantial absence of oxygen" means that oxygen is not actively supplied to the wastewater to be treated, and a small amount of oxygen is contained in the wastewater to be treated. Is also included.

本発明が対象とする廃水は、NH4NO3を含む全ての廃水
であり、特にNH4NO3濃度が1%以上の高濃度廃水が好適
である。本発明においては、この様な廃水に有機物(CO
D成分)を添加して、熱分解処理に供する。COD成分とし
ては、メタノール、エタノール、蟻酸、酢酸、フェノー
ルなどが例示される。COD成分の添加量は、廃水中に含
まれるNO3 -イオンモル数に対して等モル以下、より好ま
しくは0.1〜0.5モル程度である。メタノールをCOD成分
とする場合の反応は、下式で表わされる。
Wastewater to which the present invention is directed are all wastewater containing NH 4 NO 3, is particularly preferred NH 4 NO 3 high-concentration waste water concentration of 1% or more. In the present invention, such wastewater is treated with organic matter (CO
D)) and subject to thermal decomposition. Examples of the COD component include methanol, ethanol, formic acid, acetic acid, and phenol. Amount of COD components, NO 3 contained in the waste water - equimolar to ion molar number or less, more preferably about 0.1 to 0.5 moles. The reaction when methanol is used as the COD component is represented by the following formula.

NH4NO3+1/3CH3OH→ N2+1/3CO2+8/3H2O 本発明方法は、pH約1〜11.5、より好ましくは3〜9
で効率良く実施される。
NH 4 NO 3 + 1 / 3CH 3 OH → N 2 + 1 / 3CO 2 + 8 / 3H 2 O The method of the present invention is carried out at a pH of about 1 to 11.5, more preferably 3 to 9
Is implemented efficiently.

本発明で使用する触媒活性成分としては、貴金属系と
して、ルテニウム、ロジウムパラジウム、オスミウム、
イリジウム、白金及び金並びにこれ等の水に対し不溶性
乃至難溶性の化合物が、また卑金属系として、鉄、コバ
ルト、マンガン、タングステン、ニッケルおよびマグネ
シウムなどが挙げられ、これ等の1種又は2種以上を使
用することが出来る。不溶性乃至難溶性の貴金属化合物
としては、二塩化ルテニウム、二塩化白金、硫化ルテニ
ウム、硫化ロジウムなどが例示される。また、必要に応
じて、これらの触媒活性成分にはテルル、セレン、ラン
タンなどの助触媒成分を併用することにより、触媒活性
成分の活性増大、触媒体の耐熱性、耐久性、機械的強度
の向上などを図ることができる。これ等の触媒活性成分
および助触媒成分は、常法に従つて、チタニア、ジルコ
ニア、アルミナ、シリカ、アルミナ−シリカ、活性炭、
或いはニツケル、ニツケル−クロム、ニツケル−クロム
−アルミニウム、ニツケル−クロム−鉄等の金属多孔体
などの単体に担持して使用する。触媒活性成分の担持量
は、通常担持重量の0.05〜25%程度、好ましくは0.5〜
3%程度である。また、助触媒成分の使用量は、触媒活
性成分に対し、0.01〜30%程度である。触媒は、球状、
ペレツト状、円柱状、破砕片状、粉末状、ハニカム状等
の種々の形態の担体に担持した状態で使用する。反応塔
容積は、固体床の場合には、液の空間速度が0.5〜101/h
r(空塔基準)、より好ましくは1〜51/hr(空塔基準)
となる様にするのが良い。固体床で使用する触媒の大き
さは通常約3〜50mm、より好ましくは約5〜25mmであ
る。流動床の場合には、反応塔内で触媒が流動床を形成
し得る量、通常0.5〜20%、より好ましくは0.5〜1%を
廃水にスラリー状に懸濁させ、使用する。流動床におけ
る実用上の操作に当つては触媒を廃水中にスラリー状に
懸濁させた状態で反応塔に供給し、反応終了後排出させ
た処理済廃水から触媒を沈降、遠心分離等の適当な方法
で分離回収し、再度使用する。従つて処理済廃水からの
触媒分離の容易さを考慮すれば、流動床に使用する触媒
の粒度は約0.15〜約0.5mm程度とすることがより好まし
い。
As the catalytically active component used in the present invention, as a noble metal, ruthenium, rhodium palladium, osmium,
Iridium, platinum and gold, and compounds insoluble or hardly soluble in water such as iron, cobalt, manganese, tungsten, nickel and magnesium are listed as base metals, and one or more of these may be used. Can be used. Examples of the insoluble or hardly soluble noble metal compounds include ruthenium dichloride, platinum dichloride, ruthenium sulfide, and rhodium sulfide. In addition, if necessary, by using a co-catalyst component such as tellurium, selenium, or lanthanum together with these catalytically active components, the activity of the catalytically active component can be increased, and the heat resistance, durability, and mechanical strength of the catalyst can be improved. Improvement can be achieved. These catalytically active components and co-catalyst components are prepared by titania, zirconia, alumina, silica, alumina-silica, activated carbon,
Alternatively, it is used by being supported on a simple substance such as a porous metal such as nickel, nickel-chromium, nickel-chromium-aluminum, nickel-chromium-iron and the like. The loading amount of the catalytically active component is usually about 0.05 to 25% of the loading weight, preferably 0.5 to 25%.
It is about 3%. The amount of the promoter component used is about 0.01 to 30% based on the catalytically active component. The catalyst is spherical,
It is used in a state of being supported on a carrier in various forms such as a pellet, a column, a fragment, a powder, and a honeycomb. When the reaction column volume is a solid bed, the liquid space velocity is 0.5 to 10 1 / h
r (superficial basis), more preferably 1 to 5 1 / hr (superficial reference)
It is better to be. The size of the catalyst used in the solid bed is usually about 3 to 50 mm, more preferably about 5 to 25 mm. In the case of a fluidized bed, an amount that allows the catalyst to form a fluidized bed in the reaction tower, usually 0.5 to 20%, more preferably 0.5 to 1%, is used by suspending it in a slurry state in wastewater. In practical operation in a fluidized bed, the catalyst is supplied to the reaction tower in a state of being suspended in a slurry state in wastewater, and after the reaction is completed, the catalyst is settled from the treated wastewater discharged and centrifuged. Separation and recovery by a suitable method and reused. Therefore, considering the ease of separating the catalyst from the treated wastewater, the particle size of the catalyst used in the fluidized bed is more preferably about 0.15 to about 0.5 mm.

反応時の温度は、通常100〜370℃、より好ましくは20
0〜300℃とする。反応時の温度が高い程、NH4 +イオン及
びNO3 -イオンの除去率が高まり且つ反応塔内での廃水の
滞留時間も短縮されるが、反面に於て設備費が大となる
ので、廃水の種類、要求される処理の程度、運転費、建
設費等を総合的に考慮して定めれば良い。従つて反応時
の圧力は、最低限所定温度に於て廃水が液相を保つ圧力
であれば良い。
The temperature during the reaction is usually 100 to 370 ° C., more preferably 20 to 370 ° C.
0-300 ° C. Higher temperature during the reaction, NH 4 + ions and NO 3 - but is shortened residence time of the waste water removal rate is increased and reaction column of ion, because equipment costs become large At a contrary, It may be determined by comprehensively considering the type of wastewater, the required degree of treatment, operating costs, construction costs, and the like. Therefore, the pressure during the reaction may be a pressure at which the wastewater keeps a liquid phase at a predetermined temperature.

NH4NO3含有廃水にCOD成分とともにアンモニアを加え
て0.1<NH3−N/NO3−N≦2(モル比)とした廃水を湿
式熱分解する場合の反応条件も上記と同様で良い。
NH 4 NO 3 reaction conditions for the wastewater was the waste water containing ammonia is added to with COD components 0.1 <NH 3 -N / NO 3 -N ≦ 2 ( molar ratio) decomposing wet heat also may be the same as described above.

NH4NO3含有廃水にCOD成分とともに酸または処理条件
下に酸を形成する物質を添加して、廃水の湿式熱分解す
る場合の反応条件も上記と同様で良い。
NH 4 NO 3 in containing waste water by adding a substance which forms an acid to an acid or treated conditions with COD components, also the reaction conditions for wet thermal decomposition of the waste water may be the same as described above.

添加する酸としては、硫酸、硝酸、塩酸などがあり、
硫酸が最も好ましい。酸生成物質としては、硫黄、硫黄
化合物(チオ硫酸、チオシアン酸、チオ尿素、チオエー
テル、チオフェノールなど)が例示される。或いは、コ
ークス路ガス精製装置などから排出される硫黄化合物を
酸精製物質源としても良い。酸または処理条件下に酸を
形成する物質のNH4NO3含有廃水に対する配合量は、廃水
中に含まれるNa、Kなどのアルカリ金属の塩乃至イオン
の量の合計モル数に相当する程度の量とする。
Examples of the acid to be added include sulfuric acid, nitric acid, and hydrochloric acid.
Sulfuric acid is most preferred. Examples of the acid generating substance include sulfur and sulfur compounds (thiosulfuric acid, thiocyanic acid, thiourea, thioether, thiophenol and the like). Alternatively, a sulfur compound discharged from a coke gas purification device or the like may be used as an acid purification substance source. The amount of the acid or the substance that forms an acid under the treatment conditions with respect to the NH 4 NO 3 -containing wastewater is such that the amount corresponds to the total number of moles of salts or ions of alkali metals such as Na and K contained in the wastewater. Amount.

NH4NO3含有廃水にCOD成分およびアンモニアを加えて
0.1<NH3−N/NO3−N≦2(モル比)とし、更に酸若し
くは酸生成物質を加えた廃水を湿式熱分解する場合の反
応条件も上記と同様で良い。
Adding COD components and ammonia to NH 4 NO 3 containing waste water
The reaction conditions in the case of 0.1 <NH 3 -N / NO 3 -N ≦ 2 (molar ratio) and wet pyrolysis of wastewater to which an acid or an acid-generating substance is added may be the same as the above.

なお、本発明において、COD成分源或いはCOD成分源と
アンモニア源としても、これらを含む各種の廃水を使用
することが出来る。この場合には、コークス路プラント
並びに石炭のガス化および液化プラントで副生するガス
液、これらプラントでのガス精製に伴って生ずる各種廃
水、湿式脱流塔および湿式シアン塔からの廃水含油水、
活性汚泥処理水、沈降汚泥活性、化学工場廃水、石油工
場廃水、し尿、下水、下水汚泥などを同時に処理するこ
とが出来る。
In the present invention, various kinds of wastewater containing these can also be used as the COD component source or the COD component source and the ammonia source. In this case, a gas liquid produced as a by-product in a coke line plant and a coal gasification and liquefaction plant, various wastewaters produced by gas purification in these plants, wastewater oil-containing water from a wet deflow tower and a wet cyan tower,
Activated sludge treated water, settled sludge activity, chemical factory wastewater, petroleum factory wastewater, night soil, sewage, sewage sludge, etc. can be simultaneously treated.

第1図は、本発明方法の一実施態様のフローチャート
を示す。
FIG. 1 shows a flowchart of one embodiment of the method of the present invention.

タンク(1)に収容された廃水原水は、ライン(3)
を通り、昇圧ポンプ(5)によりライン(7)を経て熱
交換器(9)に送られ、後述する反応塔(19)からの高
温処理水により加熱された後、ライン(11)を経て、ボ
イラー(13)を付設された加熱器(15)に送給され、所
定の温度まで、加熱される。反応が進行して、所定の温
度に維持できる定常状態に到達した場合には、ボイラー
(13)による加熱は停止される。所定の反応温度まで加
熱された廃水は、次いで、ライン(17)を経て、担持触
媒を収容した反応塔(19)に入り、酸素の実施的な不存
在下に熱処理に供される。熱処理された高温の処理水
は、ライン(21)を通って熱交換器(9)に送られ、こ
こで廃水原水の予備処理を行なった後、ライン(23)を
経て、冷却器(25)に送られ、冷却される。冷却器(2
5)には、給水ライン(27)および廃水ライン(29)が
接続されており、冷却水の供給及び廃水が常時行なわれ
ている。冷却器(25)を出た処理水は、ライン(31)を
経て気液分離器(33)に送られ、ライン(35)からの液
相とライン(37)からの気相とに分離される。液相のpH
が低すぎる場合には、ライン(39)からのpH調整剤(図
示の実施態様では、NaOH水溶液)が添加された後、系外
に取り出される。一方、ライン(37)からの気相は、バ
ルブ(41)を経て系外に取り出される。
Raw wastewater stored in the tank (1) is supplied to the line (3)
Through a line (7) by a pressurizing pump (5) to a heat exchanger (9) and heated by high-temperature treated water from a reaction tower (19) described later, and then through a line (11), It is fed to a heater (15) provided with a boiler (13) and is heated to a predetermined temperature. When the reaction proceeds and reaches a steady state in which a predetermined temperature can be maintained, the heating by the boiler (13) is stopped. The wastewater heated to the predetermined reaction temperature then enters via line (17) the reaction tower (19) containing the supported catalyst and is subjected to a heat treatment in the practical absence of oxygen. The heat-treated high-temperature treated water is sent to a heat exchanger (9) through a line (21), where it is subjected to a preliminary treatment of raw wastewater, and then to a cooler (25) through a line (23). And cooled. Cooler (2
The water supply line (27) and the wastewater line (29) are connected to 5), and the supply of the cooling water and the wastewater are always performed. The treated water leaving the cooler (25) is sent to a gas-liquid separator (33) via a line (31) and is separated into a liquid phase from a line (35) and a gas phase from a line (37). You. Liquid phase pH
If the pH is too low, the pH adjuster (NaOH aqueous solution in the illustrated embodiment) from line (39) is added and then taken out of the system. On the other hand, the gas phase from the line (37) is taken out of the system via the valve (41).

なお、反応塔(19)には、温度検知装置(43)を付設
しておくことにより、反応塔(19)内の温度に応じて、
バルブ(47)を開き、ライン(7)を通る廃水の一部を
バイパスライン(45)を経て反応器(19)に直接供給す
ることができる。
In addition, by attaching a temperature detector (43) to the reaction tower (19), according to the temperature in the reaction tower (19),
The valve (47) is opened and a part of the wastewater passing through the line (7) can be fed directly to the reactor (19) via the bypass line (45).

反応開始に先立って、系内を所定の圧力まで高めるた
めに、空気ボンベからライン(49)を経て高圧空気を気
液分離器(33)に挿入しておくことも出来る。
Prior to the start of the reaction, high-pressure air can be inserted into the gas-liquid separator (33) from the air cylinder via the line (49) in order to increase the inside of the system to a predetermined pressure.

また、反応処理中の系内の圧力を制御するためには、
気液分離器(33)に圧力検知装置(55)を付設しておく
ことにより、気液分離気(33)内の圧力に応じて、バル
ブ(41)の開閉度を調節することができる。
In order to control the pressure in the system during the reaction process,
By attaching the pressure detection device (55) to the gas-liquid separator (33), the opening / closing degree of the valve (41) can be adjusted according to the pressure in the gas-liquid separation gas (33).

本発明において、廃水にCOD成分を添加する場合に
は、例えば、ライン(51)からライン(3)内を通る廃
水に混合すれば良い。COD成分の添加位置は、特に限定
されず、反応器にいたるまでの任意の個所で行なうこと
ができる。
In the present invention, when the COD component is added to the wastewater, for example, it may be mixed with the wastewater passing from the line (51) to the line (3). The position at which the COD component is added is not particularly limited, and the COD component can be added at any point up to the reactor.

さらにまた、本発明において、廃水に酸または酸精製
物質(図示の装置では、硫酸)を添加する場合にも、例
えば、ライン(53)からライン(3)内を通る廃水に混
合すれば良い。酸または酸生成物質の添加位置も、特に
限定されず、反応器にいたるまでのやはり任意の個所で
行なうことができる。
Furthermore, in the present invention, when an acid or an acid-purified substance (sulfuric acid in the illustrated apparatus) is added to the wastewater, for example, it may be mixed with the wastewater passing from the line (53) to the line (3). The addition position of the acid or the acid-generating substance is not particularly limited, and the addition can be carried out at any place up to the reactor.

さらに、本発明において、廃水にアンモニアを添加す
る場合にも、例えば、ライン(57)からライン(3)を
通る廃水に混合すれば良い。アンモニアの添加位置も特
に限定されず、反応器にいたるまでの任意の個所で行な
うことができる。
Furthermore, in the present invention, when ammonia is added to the wastewater, for example, it may be mixed with the wastewater passing from the line (57) to the line (3). The position at which ammonia is added is not particularly limited, and the addition can be performed at any point up to the reactor.

発明の効果 本発明によれば、NH4NO3を高濃度で含有する廃水を甲
良く処理し、NH4 +イオン及びNO3 -イオンの濃度を大幅に
低下させることが出来る。従つて、例えば、ウラン原料
の処理工程又は使用済みウラン燃料の再処理工程から排
出され、NH4NO3濃度が10%以上にも達することがある廃
水などの処理を簡易な設備により容易に行なうことが出
来る。
According to the present invention, wastewater containing NH 4 NO 3 at a high concentration can be treated well, and the concentrations of NH 4 + ions and NO 3 ions can be significantly reduced. Accordingly, for example, wastewater discharged from a uranium raw material processing step or a spent uranium fuel reprocessing step and having an NH 4 NO 3 concentration of 10% or more can be easily processed with simple equipment. I can do it.

また、酸素の使用を必須とする前述の先願発明−IIの
場合とは異なって、酸素含有ガスの圧縮および供給設備
ならびにそのが設置場所が不要となるので、設備費用お
よび運転費用が大幅に削減され、廃水処理コストが著し
く低下する。
Also, unlike the above-mentioned prior application invention-II which requires the use of oxygen, the equipment for compressing and supplying the oxygen-containing gas and the place for installing it are not required, so that the equipment cost and the operating cost are greatly reduced. And wastewater treatment costs are significantly reduced.

実 施 例 以下実施例を示し、本発明の特徴とするところをより
一層明らかにする。
EXAMPLES Examples are shown below to further clarify features of the present invention.

実施例1 COD成分/NO3−N=0.33(モル比)となる様にCH3OHを
加えたpH6.7,NH4NO3濃度約1%(NH3−/NO3−N=1)
の廃水100mlを容量300mlのステンレススチール製オート
クレーブに収容し、250℃で90分間熱分解処理した。
Example 1 pH 6.7 with CH 3 OH added so that COD component / NO 3 −N = 0.33 (molar ratio), NH 4 NO 3 concentration about 1% (NH 3 − / NO 3 −N = 1)
Was placed in a 300 ml stainless steel autoclave and pyrolyzed at 250 ° C. for 90 minutes.

該オートクレーブには、チタニア担体にルテニウム2
重量%を担持させた径5mmの触媒10gが充填されていた。
The autoclave contains ruthenium 2 on a titania carrier.
The catalyst was packed with 10 g of a catalyst having a diameter of 5 mm and supporting the weight%.

第1表に触媒活性成分、廃水のpHおよびNH4NO3の濃度
を実施例2〜6のそれらとともに示し、また第2表に全
窒素成分分解率およびCOD、TOC成分分解率を実施例2〜
6の結果とともに示す。
Table 1 shows the catalytically active components, the pH of the wastewater and the concentration of NH 4 NO 3 together with those of Examples 2 to 6, and Table 2 shows the total nitrogen component decomposition rate and the COD and TOC component decomposition rates in Example 2. ~
6 are shown together with the results.

実施例2 実施例1で処理したものとはpHの異なるNH4NO3含有廃
水に所定量のCH3OHを加えて、CH3OH/NO3−N(モル比)
を調整した後、実施例1と同様にして熱分解処理に供し
た。
Example 2 A predetermined amount of CH 3 OH was added to NH 4 NO 3 -containing wastewater having a different pH from that treated in Example 1 to obtain CH 3 OH / NO 3 —N (molar ratio).
, And subjected to a thermal decomposition treatment in the same manner as in Example 1.

本実施例では、廃水中のNa及びKイオンのモル数に対
応する硫酸(0.013モル/)を廃水に添加した。
In this example, sulfuric acid (0.013 mol /) corresponding to the number of moles of Na and K ions in the wastewater was added to the wastewater.

実施例3 実施例1で処理したものとはpH及び濃度の異なるNH4N
O3含有廃水に所定量のCH3OHを加えて、CH3OH/NO3−N
(モル比)を調整した後、実施例1と同様にして熱分解
処理に供した。
Example 3 NH 4 N different in pH and concentration from the one treated in Example 1
A predetermined amount of CH 3 OH is added to the O 3 -containing wastewater to obtain CH 3 OH / NO 3 −N
After adjusting (molar ratio), it was subjected to a thermal decomposition treatment in the same manner as in Example 1.

実施例4 ルテニウム担持触媒に代えてチタニア担体にパラジウ
ム2重量%を担持させた径5mmの触媒を使用する以外は
実施例1と同様にして廃水の熱分解処理を行なつた。
Example 4 The wastewater was subjected to thermal decomposition treatment in the same manner as in Example 1 except that a catalyst having a diameter of 5 mm in which 2% by weight of palladium was supported on a titania carrier was used instead of the ruthenium-supported catalyst.

実施例5〜6 ルテニウム触媒に代えて実施例4で使用したと同様の
パラジウム触媒を使用する以外は実施例2とそれぞれ同
様にしてNH4NO3含有廃水の熱分解処理を行なつた。
Examples 5 to 6 The thermal decomposition treatment of NH 4 NO 3 -containing wastewater was carried out in the same manner as in Example 2 except that the same palladium catalyst as used in Example 4 was used instead of the ruthenium catalyst.

実施例7〜9 NH4NO3含有廃水にCH3OHおよびNH4OHを加え、実施例1
と同様にして廃水の熱分解処理を行なつた。
Examples 7 to 9 Example 1 was repeated by adding CH 3 OH and NH 4 OH to waste water containing NH 4 NO 3.
The wastewater was thermally decomposed in the same manner as described above.

なお、実施例8〜9においては、廃水中のNaおよびK
のモル数に対応するモル数の硫酸(0.013モル/)を
廃水に添加した。
In Examples 8 and 9, Na and K in the wastewater were used.
Of sulfuric acid (0.013 mol /) corresponding to the number of moles of was added to the wastewater.

第3表および第4表に条件および結果をそれぞれ示
す。
Tables 3 and 4 show the conditions and results, respectively.

実施例10〜12 NH4NO3含有廃水にCH3OHおよびNH4OHを加え、実施例4
と同様にして廃水の熱分解処理を行なつた。
The CH 3 OH and NH 4 OH was added to the Example 10 to 12 NH 4 NO 3 containing waste water, Example 4
The wastewater was thermally decomposed in the same manner as described above.

なお、実施例11〜12においては、廃水中のNaおよびK
のモル数に対応するモル数の硫酸(0.013モル/)を
廃水に添加した。
In Examples 11 and 12, Na and K in the wastewater were used.
Of sulfuric acid (0.013 mol /) corresponding to the number of moles of was added to the wastewater.

第3表および第4表に条件および結果をそれぞれ示
す。
Tables 3 and 4 show the conditions and results, respectively.

実施例13 NH4NO3濃度10%(NH3−N/NO3−N=1.0)の廃水(全
窒素成分濃度=35000mg/)にCH3OHを添加してCH3OH/N
O3=約0.35モルに調整するとともに、硫酸を添加してそ
のpHを1.9とした液を空間速度3.91/hr(空塔基準)とし
て高ニツケル鋼製円筒型反応器株に供給して熱分解処理
を行なつた。液の質量速度は、2.8ton/m2・hrであり、
反応器には、チタニア担体にルテニウム2重量%を担持
させた径の5mmの球形触媒が充填されており、熱分解
は、温度250℃、圧力70kg/cm2の条件下に行なわれた。
Example 13 CH 3 OH was added to wastewater (total nitrogen component concentration = 35000 mg /) having an NH 4 NO 3 concentration of 10% (NH 3 —N / NO 3 —N = 1.0) to obtain CH 3 OH / N
O 3 = as well as adjusted to about 0.35 moles, heat is supplied to the high-nickel steel cylindrical reactor strain a solution obtained by the pH to 1.9 by addition of sulfuric acid as a space velocity 3.9 1 / hr (superficial reference) Decomposition processing was performed. Mass velocity of the liquid is 2.8ton / m 2 · hr,
The reactor was filled with a spherical catalyst having a diameter of 5 mm in which 2% by weight of ruthenium was supported on a titania carrier, and the thermal decomposition was performed at a temperature of 250 ° C. and a pressure of 70 kg / cm 2 .

反応後の気液混合相を熱回収に供した後、NH4NO3の分
解により生成した窒素ガスなどを分離するために、気液
分離器を導き、分離された気相及び液相をそれぞれ間接
冷却後、系外に取り出した。なお、反応開始に先立っ
て、気液分離器に少量の空気を送り込み、圧力を70kg/c
m2に高めた後、反応を開始した。
After subjecting the gas-liquid mixed phase after the reaction to heat recovery, a gas-liquid separator is led to separate nitrogen gas and the like generated by decomposition of NH 4 NO 3 , and the separated gas phase and liquid phase are respectively separated. After indirect cooling, it was taken out of the system. Prior to the start of the reaction, a small amount of air was blown into the gas-liquid separator, and the pressure was reduced to 70 kg / c.
After increasing to m 2 , the reaction was started.

第5表にNH3、NO3、全窒素成分およびCOD,TOC成分の
分解率を示す。
Table 5 shows the decomposition rates of NH 3 , NO 3 , total nitrogen components, and COD and TOC components.

尚、気相中には、NOx及びSOxは検出されなかつた。 NOx and SOx were not detected in the gas phase.

実施例14〜30 下記の廃水を使用し且つ反応条件を採用するととも
に、触媒を第6表に示すものに代える以外は実施例13と
同様にして、廃水の処理を行なった。
Examples 14 to 30 Wastewater treatment was carried out in the same manner as in Example 13 except that the following wastewater was used and the reaction conditions were adopted, and the catalyst was changed to that shown in Table 6.

結果は、第6表に示す通りである。 The results are as shown in Table 6.

*廃水の性状及び反応条件: NH4NO3濃度=5% 全窒素濃度=17500mg/ 温度=270℃ 圧力=90kg/cm2 廃水の空間速度=1.51/hr 実施例31〜34 添加する有機物及び酸または酸性性物質を第7表に示
すものに代える以外は実施例13と同様にして廃水の処理
を行った。
* Wastewater characteristics and reaction conditions: NH 4 NO 3 concentration = 5% total nitrogen concentration = 17500Mg / temperature = 270 ° C. Pressure = 90 kg / cm 2 space velocity = 1.5 1 / hr of waste water Examples 31 to 34 Wastewater treatment was carried out in the same manner as in Example 13 except that the organic substances and the acids or acidic substances to be added were changed to those shown in Table 7.

結果を第7表に示す。 The results are shown in Table 7.

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

第1図は、本発明方法の実施態様の一例の概要を示すフ
ローチャートである。 (1)……廃水タンク (5)……昇圧ポンプ (9)……熱交換器 (13)……ボイラー (15)……加熱器 (19)……反応塔 (25)……冷却器 (27)……給水ライン (29)……排水ライン (33)……気液分離器 (35)……液相ライン (37)……気相ライン (39)……pH調整剤供給ライン (43)……温度検知装置 (45)……バイパスライン (49)……高圧空気供給ライン (51)……COD成分供給ライン (53)……酸または酸生成物質供給ライン (55)……圧力検知装置 (57)……アンモニア供給ライン
FIG. 1 is a flowchart showing an outline of an example of an embodiment of the method of the present invention. (1) ... Waste water tank (5) ... Pressure pump (9) ... Heat exchanger (13) ... Boiler (15) ... Heating device (19) ... Reaction tower (25) ... Cooler ( 27) Water supply line (29) Drain line (33) Gas-liquid separator (35) Liquid phase line (37) Gas phase line (39) pH adjuster supply line (43 ) Temperature detector (45) Bypass line (49) High pressure air supply line (51) COD component supply line (53) Acid or acid generating substance supply line (55) Pressure detection Equipment (57)… Ammonia supply line

フロントページの続き (58)調査した分野(Int.Cl.6,DB名) C02F 1/00 - 1/78 Continuation of front page (58) Field surveyed (Int. Cl. 6 , DB name) C02F 1/00-1/78

Claims (4)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】0.1<有機物/NO3−N≦0.5(モル比)とな
る様に有機物を加えた硝酸アンモニウム含有廃水を貴金
属及びその不溶性又は難溶性化合物並びに卑金属からな
る群から選ばれた少なくとも1種を活性成分とする担持
触媒の存在下且つ酸素の実質的な不存在下にpH約1〜1
1.5、温度100〜370℃で湿式熱分解することを特徴とす
る硝酸アンモニウム含有廃水の処理方法。
1. An ammonium nitrate-containing wastewater to which an organic substance is added such that 0.1 <organic substance / NO 3 -N ≦ 0.5 (molar ratio) is obtained by mixing at least one selected from the group consisting of a noble metal, an insoluble or hardly soluble compound thereof, and a base metal. The pH is about 1 to 1 in the presence of a supported catalyst containing a species as an active ingredient and in the substantial absence of oxygen.
1.5. A method for treating wastewater containing ammonium nitrate, comprising performing wet pyrolysis at a temperature of 100 to 370 ° C.
【請求項2】0.1<有機物/NO3−N≦0.5(モル比)とな
る様に有機物を加え且つ 0.1<NH3−N/NO3−N≦2(モル比)となる様にアンモ
ニアを加えた硝酸アンモニウム含有廃水を貴金属及びそ
の不溶性又は難溶性化合物並びに卑金属からなる群から
選ばれた少なくとも1種の活性成分とする担持触媒の存
在下且つ酸素の実質的な不存在下にpH約1〜11.5、温度
100〜370℃で湿式熱分解することを特徴とする硝酸アン
モニウム含有廃水の処理方法。
2. An organic substance is added so that 0.1 <organic substance / NO 3 -N ≦ 0.5 (molar ratio), and ammonia is added so that 0.1 <NH 3 -N / NO 3 -N ≦ 2 (molar ratio). The added ammonium nitrate-containing wastewater has a pH of about 1 to about 1 in the presence of a supported catalyst containing at least one active component selected from the group consisting of a noble metal and an insoluble or hardly soluble compound and a base metal and in the substantial absence of oxygen. 11.5, temperature
A method for treating wastewater containing ammonium nitrate, wherein the wastewater is subjected to wet pyrolysis at 100 to 370 ° C.
【請求項3】0.1<有機物/NO3−N≦0.5(モル比)とな
る様に有機物を加え且つ酸及び酸生成物質の少なくとも
1種を添加した硝酸アンモニウム含有廃水を貴金属及び
その不溶性又は難溶性化合物並びに卑金属からなる群か
ら選ばれた少なくとも1種を活性成分とする担持触媒の
存在下且つ酸素の実質的な不存在下にpH約1〜11.5、温
度100〜370℃で湿式熱分解することを特徴とする硝酸ア
ンモニウム含有廃水の処理方法。
3. An ammonium nitrate-containing wastewater to which an organic substance is added so that 0.1 <organic substance / NO 3 -N ≦ 0.5 (molar ratio) and at least one of an acid and an acid-generating substance is added, the noble metal and its insoluble or hardly soluble Wet pyrolysis at a pH of about 1 to 11.5 and a temperature of 100 to 370 ° C. in the presence of a supported catalyst containing at least one selected from the group consisting of compounds and base metals as active ingredients and in the substantial absence of oxygen; A method for treating ammonium nitrate-containing wastewater.
【請求項4】0.1<有機物/NO3−N≦0.5(モル比)とな
る様に有機物を加え、 0.1<NH3−N/NO3−N≦2(モル比)となる様にアンモ
ニアを加え且つ酸及び酸生成物質の少なくとも1種を添
加した硝酸アンモニウム含有廃水を貴金属及びその不溶
性又は難溶性化合物並びに卑金属からなる群から選ばれ
た少なくとも1種を活性成分とする担持触媒の存在下且
つ酸素の実質的な不存在下にpH約1〜11.5、温度100〜3
70℃で湿式熱分解することを特徴とする硝酸アンモニウ
ム含有廃水の処理方法。
4. An organic substance is added so that 0.1 <organic substance / NO 3 -N ≦ 0.5 (molar ratio), and ammonia is added so that 0.1 <NH 3 -N / NO 3 -N ≦ 2 (molar ratio). The ammonium nitrate-containing wastewater to which at least one of an acid and an acid-generating substance is added and which is treated with oxygen in the presence of a supported catalyst containing as an active ingredient at least one selected from the group consisting of noble metals and insoluble or hardly soluble compounds thereof and base metals. PH about 1-11.5, temperature 100-3 in the substantial absence of
A method for treating ammonium nitrate-containing wastewater, comprising performing wet pyrolysis at 70 ° C.
JP16083890A 1990-06-18 1990-06-18 Treatment method for wastewater containing ammonium nitrate Expired - Fee Related JP2899719B2 (en)

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JP2899719B2 true JP2899719B2 (en) 1999-06-02

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