JP2004016892A

JP2004016892A - Exhaust gas treatment method and apparatus therefor

Info

Publication number: JP2004016892A
Application number: JP2002173783A
Authority: JP
Inventors: Michio Fujiwara; 藤原　通雄; Hiroshi Yamamoto; 山元　寛; Shinji Izaki; 井崎　伸二; Junji Kobayashi; 小林　淳二; Jiro Naka; 中　慈朗
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2002-06-14
Filing date: 2002-06-14
Publication date: 2004-01-22

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust gas treatment method which can efficiently form OH radicals, can suppress the amounts of an ozonized gas and hydrogen peroxide supplied, and can reduce cost; and an apparatus therefor. <P>SOLUTION: In the exhaust gas treatment method, a component to be treated contained in an exhaust gas flowing through an exhaust gas pathway is decomposed by bringing the exhaust gas into contact with active water containing an ozonized gas, hydrogen peroxide, and water. The active water is obtained by introducing an ozonized gas into a mixing and reacting vessel, then spraying hydrogen peroxide into the vessel to accelerate an OH radical formation reaction, and mixing with water. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、排ガス処理方法およびそのための装置に関するものであり、詳しくは、ＯＨラジカルを高効率で生成することができ、オゾン化ガスおよび過酸化水素の供給量を抑制することができ、コストの低下が可能となる排ガス処理方法およびそのための装置に関するものである。
【０００２】
【従来の技術】
図１２は例えば特開２０００−１８５２１７号公報に示された焼却炉排ガス中のダイオキシン類の分解が可能な排ガス処理方法および装置の概略構成図である。図１２において、５９は焼却炉、６０は排ガス通路、６１は減温塔、６２は二流体噴霧ノズルで構成された活性水供給部、６３は電気集塵機、６４は誘引送風機、６５は煙突、５１はオゾン含有水製造装置、５２はオゾン化ガス供給配管、６７はオゾン含有水供給配管である。図１３はオゾン含有水製造装置のフロー図である。図１３において、５１ａは水ポンプ、５１ｂ，５１ｃは逆止弁、５１ｄはオゾン発生器、５１ｅはエジェクター、５１ｆは気液混合器、５１ｇは過酸化水素供給装置である。
次に動作について説明する。図１２において、可燃性の廃棄物などが焼却炉５９で焼却されると約８５０℃程度の燃焼ガスが発生する。この燃焼ガスは図示されていないボイラーなどを介して、６５０℃以下に冷却された後、減温塔６１に誘引送風機６４により誘引される。減温塔６１では減温塔に取り付けられた活性水供給部６２から、冷却水にオゾンが含まれたオゾン含有水、過酸化水素およびオゾン化ガスからなる活性水を燃焼ガス（排ガスとも呼ぶ）に粒子状に噴霧供給することにより、燃焼ガスを約２００℃まで急速に冷却する。冷却された後の燃焼ガスは電気集塵機６３で媒塵が除去された後、誘引送風機６４を経て煙突６５から大気に排気される。
また図１３において、活性水は、空気または酸素を原料としてオゾン発生器５１ｄで発生したオゾン化ガス（オゾンと空気または酸素の混合気体）と、該オゾン化ガスをエジェクター５１ｅの吸引作用と気液混合器５１ｆにより冷水中に溶け込ませて得られるオゾン含有水と、過酸化水素供給装置５１ｇから供給される過酸化水素とから構成される。この活性水を減温塔内の排ガスに活性水供給部から粒子状に噴霧・供給する。
従来の排ガス処理装置は以上のように構成されており、減温塔内で噴霧流体としての活性水を粒子状に燃焼ガス（排ガスとも呼ぶ）に供給して急速冷却を行い、この冷却過程で、活性水中のオゾン化ガスと過酸化水素の接触化学反応や、オゾン化ガスの熱分解反応などにより強力な酸化力をもつＯＨラジカルが生成する。この従来の排ガス処理装置の特徴は、生成したＯＨラジカルと燃焼ガス中のダイオキシン類が反応することで、ダイオキシン類の前躯体物質の分解や、ダイオキシン類の分解が行われることである。さらにダイオキシン類の分解が行われた後の２００℃程度の燃焼ガスは、燃焼ガス中の煤塵が電気集塵機で大半が集塵された後、煙突から排気される。この結果、煙突から排出される排ガス中のダイオキシン類の低減とともに、電気集塵機で集塵された煤塵のダイオキシン類も大幅に低減可能となる。
【０００３】
【発明が解決しようとする課題】
前記従来の排ガス処理装置は、図１２、１３のように構成されており、その作用は燃焼ガス中（以後排ガスと呼ぶ）に活性水を粒子状に供給し、活性水に含まれるオゾン含有水、オゾン化ガスおよび過酸化水素により、ダイオキシン類の分解に強力な作用を持つと考えられるＯＨラジカルを化学反応、熱分解反応により効率的に大量に生成させ、ダイオキシン類を分解するものであるが、このとき、ＯＨラジカルと排ガス中のダイオキシン類を効率良く反応させることが重要である。しかしながら、従来の装置では、減温塔内でのオゾン化ガスと過酸化水素の反応によるＯＨラジカルの生成効率があまり高くないことが判明した。このため、排ガス中のダイオキシン類を分解するためには多量のオゾン化ガスと過酸化水素の供給が必要であった。
【０００４】
したがって本発明の目的は、上記問題点を解決することにあり、ＯＨラジカルを高効率で生成することができ、オゾン化ガスおよび過酸化水素の供給量を抑制することができ、コストの低下が可能となる排ガス処理方法およびそのための装置を提供することである。
【０００５】
【課題を解決するための手段】
請求項１の発明は、オゾン化ガス、過酸化水素および水を含む活性水を、排ガス通路を流れる排ガスと接触させ、前記排ガスに含まれる被処理成分を分解する排ガス処理方法において、
前記活性水が、前記オゾン化ガスの導入された混合反応器に前記過酸化水素を噴霧し、ＯＨラジカル生成反応を促進し、続いて前記水と混合して得られたものであることを特徴とする排ガス処理方法である。
請求項２の発明は、過酸化水素に超音波振動を施した後、混合反応器に噴霧することを特徴とする請求項１に記載の排ガス処理方法である。
請求項３の発明は、過酸化水素を加熱した後、混合反応器に噴霧することを特徴とする請求項１に記載の排ガス処理方法である。
請求項４の発明は、過酸化水素を加熱蒸気とした後、混合反応器に噴霧することを特徴とする請求項３に記載の排ガス処理方法である。
請求項５の発明は、過酸化水素を濃縮するとともに加熱蒸気とした後、混合反応器に噴霧することを特徴とする請求項４に記載の排ガス処理方法である。
請求項６の発明は、活性水を排ガスと接触させた後に、その下流の排ガス通路にオゾン分解処理手段を設け、前記排ガス通路に残存するオゾンを分解することを特徴とする請求項１に記載の排ガス処理方法である。
請求項７の発明は、オゾン分解処理手段が、活性炭微粒子を排ガス通路に噴霧する手段であることを特徴とする請求項６に記載の排ガス処理方法である。
請求項８の発明は、オゾン分解処理手段が、排ガスを活性炭微粒子が充填された充填塔に通過させる手段であることを特徴とする請求項６に記載の排ガス処理方法である。
請求項９の発明は、活性水を排ガスと接触させた後に、その下流の排ガス通路にアンモニア水を噴霧し、前記排ガスに含まれる窒素酸化物を低減することを特徴とする請求項１に記載の排ガス処理方法である。
請求項１０の発明は、排ガスが上昇および下降方向に順次流れるように排ガス通路を構成し、前記上昇および下降区間においてそれぞれ活性水が前記排ガスと接触するようにするとともに、前記排ガス通路の活性水の残余を排出可能にしたことを特徴とする請求項１に記載の排ガス処理方法である。
請求項１１の発明は、排ガス通路において排ガスとオゾン化ガスとを接触させ、続いてその下流の排ガス通路内に排ガス流れ方向に対し所定の間隔で過酸化水素を噴霧することにより、前記排ガスに含まれる被処理成分を分解することを特徴とする排ガス処理方法である。
請求項１２の発明は、オゾン化ガスを供給する排ガス通路内の排ガスの温度を２５０℃以下に制御することを特徴とする請求項１１に記載の排ガス処理方法である。
請求項１３の発明は、過酸化水素を空気とともに排ガス通路内に噴霧することを特徴とする請求項１１に記載の排ガス処理方法である。
請求項１４の発明は、過酸化水素に超音波振動を施した後、排ガス通路内に噴霧することを特徴とする請求項１１に記載の排ガス処理方法である。
請求項１５の発明は、過酸化水素を加熱した後、排ガス通路内に噴霧することを特徴とする請求項１１に記載の排ガス処理方法である。
請求項１６の発明は、過酸化水素に含まれる水分を加熱蒸発させ高濃度化した後、排ガス通路内に噴霧することを特徴とする請求項１１に記載の排ガス処理方法である。
請求項１７の発明は、過酸化水素および空気を加熱して排ガス通路内に噴霧することを特徴とする請求項１３に記載の排ガス処理方法である。
請求項１８の発明は、排ガス温度測定手段、排ガス量測定手段、オゾン量・過酸化水素量決定手段、オゾン発生器、過酸化水素供給装置、混合反応器および活性水供給手段を備え、前記排ガス温度測定手段により排ガス通路を流れる排ガス温度を測定するとともに前記排ガス量測定手段により前記排ガス通路内における排ガス流量を測定し、これらの測定結果に基づき、前記オゾン量・過酸化水素量決定手段が、被処理成分の分解に必要なオゾンおよび過酸化水素量を決定し、この決定された量に基いて前記オゾン発生器および過酸化水素供給装置が前記混合反応器内にオゾン化ガスおよび過酸化水素を導入し、ここで、前記過酸化水素が前記オゾン化ガスの導入された混合反応器に噴霧され、続いて水と混合することにより活性水を得、この活性水を、前記活性水供給手段により排ガス通路を流れる排ガスと接触させ、前記排ガスに含まれる被処理成分を分解するようにした、請求項１に記載の方法を行うための排ガス処理装置である。
請求項１９の発明は、排ガス処理装置が冷却水量決定手段および冷却水量制御器をさらに備え、排ガス温度測定手段により測定された排ガス通路を流れる排ガス温度が、排ガス温度設定値よりも高い場合、冷却水量決定手段により決定された量の冷却水が、排ガス通路内に導入され温度制御を行うことを特徴とする請求項１８に記載の排ガス処理装置である。
【０００６】
【発明の実施の形態】
実施の形態１．
以下、本発明の実施の形態１を図に基づいて説明する。図１は本発明の実施の形態１における活性水製造装置と活性水供給部を示す図である。
図１において、１は活性水生成装置、１ａはオゾン発生装置、１ｂは水供給ポンプ、１ｃは空気供給装置、１ｄは混合反応器、１ｅは過酸化水素供給装置、１ｆは過酸化水素用逆止弁、１ｇはオゾン化ガス用逆止弁、１ｈは過酸化水素噴霧ノズル、１ｉは空気供給配管、１ｊは過酸化水素供給配管、２は活性水用配管、１２は活性水噴霧ノズル、１７は活性水用水配管である。
【０００７】
作用について説明する。本実施の形態では、オゾン発生装置１ａにより生成されたオゾン化ガスが、オゾン化ガス用逆止弁１ｇを介して円筒形の混合反応器１ｄの中に導入される。続いて過酸化水素供給装置１ｅから供給される過酸化水素が、過酸化水素用防止弁１ｆおよび過酸化水素供給配管１ｊを介して混合反応器１ｄの中に導入される。このとき過酸化水素の導入は、混合反応器１ｄ内に設けられた過酸化水素噴霧ノズル１ｈからの噴霧により行われる。すなわち、空気供給装置１ｃおよび空気供給配管１ｉから供給される空気（エア）とともに過酸化水素が過酸化水素噴霧ノズル１ｈによって、二流体噴霧される。このとき過酸化水素は微粒子化されるために、オゾン化ガスと効率よく混合して、ＯＨラジカルが多量に発生する。ＯＨラジカルを多量に含むオゾン化ガスは、活性水供給部である活性水噴霧ノズル１２に導かれ、水供給ポンプ１ｂおよび活性水用水配管１７から供給された水と混合され、活性水となり、排ガス中に噴霧される。
図２は、本実施の形態における、混合反応器内の滞留時間と残存オゾン率およびＯＨラジカル濃度との関係を示す図である。ＯＨラジカル濃度は残存オゾン率の実験結果から推定した。なお比較として従来方式（混合反応器内に過酸化水素を噴霧せずに水とともに導入したもの）も併せて示した。図２の結果から、従来方式では、混合反応器内でオゾン化ガスと過酸化水素が十分に接触していないために、滞留時間を長くしてもオゾン化ガスが多量に残存していることが分かった。その結果からＯＨラジカルの生成効率が高くなく、その濃度が低いことが推定される。しかし、本実施の形態では、混合反応器内でオゾン化ガスと過酸化水素が十分に接触するために、残存オゾンが少なく、従って、ＯＨラジカルの生成効率が高く多量のＯＨラジカルが生成されていることが推定される。
【０００８】
実施の形態２．
以下、本発明の実施の形態２を図３に基づいて説明する。図３は本発明の実施の形態２における活性水製造装置と活性水供給部を示す図である。
図３において、１ｋは超音波発生装置、１ｍは過酸化水素微粒子化装置、１ｎは空気供給装置である。その他の符号は、図１と同じである。
【０００９】
作用について説明する。本実施の形態においても、実施の形態１と同様に、円筒形の混合反応器１ｄの中にオゾン化ガスを導入し、同時に過酸化水素およびエアを混合反応器の中に二流体噴霧する。本実施の形態では、過酸化水素微粒子化装置１ｍを設けたことに特徴があり、超音波発生装置１ｋにより、過酸化水素に予め超音波振動を与え、そこに空気供給装置１ｎからエアを導入することにより、過酸化水素は微粒子化され、混合反応器内の過酸化水素噴霧ノズル１ｈに導かれ、混合反応器１ｄ内に二流体噴霧する。このとき過酸化水素はさらに微粒子化されるために、オゾン化ガスと効率よく混合し、ＯＨラジカルの発生量は増大する。ＯＨラジカルを多量に含むオゾン化ガスは、活性水供給部である活性水噴霧ノズル１２に導かれ、水供給ポンプ１ｂおよび活性水用水配管１７から供給された水と混合され、活性水となり、排ガス中に噴霧される。
【００１０】
実施の形態３．
以下、本発明の実施の形態３を図４に基づいて説明する。図４は本発明の実施の形態３における活性水製造装置と活性水供給部を示す図である。
図４において、１ｏは活性水ヒーターである。その他の符号は、図１と同じである。
【００１１】
作用について説明する。本実施の形態においても、実施の形態１と同様に、円筒形の混合反応器１ｄの中にオゾン化ガスを導入し、同時に過酸化水素およびエアを混合反応器の中に二流体噴霧する。本実施の形態では、活性水ヒーター１ｏにより過酸化水素を予め高温加熱し、過酸化水素の活性を高めておき、混合反応器１ｄ内の過酸化水素噴霧ノズル１ｈに導き、二流体噴霧する。このとき過酸化水素は活性が高いため、オゾン化ガスと混合したとき、ＯＨラジカルが多量に発生する。ＯＨラジカルを多量に含むオゾン化ガスは、活性水供給部である活性水噴霧ノズル１２に導かれ、水供給ポンプ１ｂおよび活性水用水配管１７から供給された水と混合され、活性水となり、排ガス中に噴霧される。
【００１２】
実施の形態４．
以下、本発明の実施の形態４を図５に基づいて説明する。図５は本発明の実施の形態４における活性水製造装置と活性水供給部を示す図である。
図５において、１ｐは加熱蒸気供給装置、１ｑは逆止弁、１ｒは圧力弁である。その他の符号は、図１と同じである。
【００１３】
作用について説明する。本実施の形態においても、実施の形態１と同様に、円筒形の混合反応器１ｄの中にオゾン化ガスを導入し、同時に過酸化水素およびエアを混合反応器の中に二流体噴霧する。本実施の形態では、加熱蒸気供給装置１ｐにより過酸化水素を予め高温加熱し加熱蒸気として、過酸化水素の活性を高めさらに蒸気状とすることで、オゾン化ガスとの接触反応特性を高めておいた上で、混合反応器１ｄ内の過酸化水素噴霧ノズル１ｈに導き、二流体噴霧する。このとき過酸化水素は活性が高いために、オゾン化ガスと混合したとき、ＯＨラジカルが多量に発生する。ＯＨラジカルを多量に含むオゾン化ガスは、活性水供給部である活性水噴霧ノズル１２に導かれ、水供給ポンプ１ｂおよび活性水用水配管１７から供給された水と混合され、活性水となり、排ガス中に噴霧される。
【００１４】
実施の形態５．
以下、本発明の実施の形態５を図６に基づいて説明する。図６は本発明の実施の形態５における活性水製造装置と活性水供給部を示す図である。
図６において、１ｓは水蒸気排出管である。その他の符号は、図１、図５と同じである。
【００１５】
作用について説明する。本実施の形態においても、実施の形態４と同様に、円筒形の混合反応器１ｄの中にオゾン化ガスを導入し、同時に過酸化水素およびエアを混合反応器の中に二流体噴霧する。本実施の形態では、加熱蒸気供給装置１ｐにより過酸化水素を予め高温加熱し加熱蒸気とするとともに、水蒸気排出管１ｓにより水蒸気を蒸発させ、高濃度の過酸化水素とすることで、過酸化水素の活性を高め、混合反応器１ｄ内の過酸化水素噴霧ノズル１ｈに導き、二流体噴霧する。このとき過酸化水素は活性が高くかつ高濃度であるために、オゾン化ガスと混合したとき、ＯＨラジカルが多量に発生する。活性水供給部である活性水噴霧ノズル１２に導かれ、水供給ポンプ１ｂおよび活性水用水配管１７から供給された水と混合され、活性水となり、排ガス中に噴霧される。
【００１６】
実施の形態６．
以下、本発明の実施の形態６を図７に基づいて説明する。図７は本発明の実施の形態６における活性水製造装置とオゾン分解処理装置を備えた焼却炉システムを示す図である。
図７において、２０はオゾン分解処理装置である。その他の符号は、図１および図１２と同じである。
【００１７】
作用について説明する。本実施の形態では、ダイオキシンを分解した後の排ガス通路に設置したオゾン分解処理装置２０により、活性水が供給されたあとの下流側の排ガス通路に残存するオゾンを分解する。オゾンを分解処理する手段は、例えば、オゾンを含む排ガスに活性炭微粒子を噴霧する方法である。あるいは、その手段として、活性炭粒が充填された充填塔を通過させるようにした方法である。
【００１８】
実施の形態７．
以下、本発明の実施の形態７を図８に基づいて説明する。図８は本発明の実施の形態７における活性水噴霧装置とアンモニア水供給装置を備えた焼却炉システムを示す図である。
図７において、２１はアンモニア水供給装置、２１ａはアンモニア水噴霧装置である。その他の符号は、図１および図１２と同じである。
【００１９】
作用について説明する。本実施の形態では、ダイオキシンを分解した後の排ガス通路に設置したアンモニア水供給装置２１およびアンモニア水噴霧装置２１ａにより、排ガス通路にアンモニア水が噴霧され、窒素酸化物が還元し窒素ガスとなり、有害な窒素酸化物を低減する。アンモニア水を噴霧する手段として、アンモニア水を微粒子状にして噴霧供給することにより、排ガスとの接触が増え、窒素酸化物を大幅に低減することができる。
【００２０】
実施の形態８．
以下、本発明の実施の形態８を図９に基づいて説明する。図９は本発明の実施の形態８における排ガス通路と複数設置した活性水噴霧部および排水穴を示す図である。
図９において、１０は排ガス通路、１２ａ、１２ｂ、１２ｃ、１２ｄはそれぞれ活性水噴霧ノズル、２２は排ガス、２３１は排水通路、２３２は排水穴、２４は排水タンクである。その他の符号は、図１２および１３で示した従来の排ガス処理装置と同じである。
【００２１】
作用について説明する。本実施の形態では、排ガス２２が排ガス通路１０（従来の減温塔に相当）内で上昇および下降方向に順次流れるようになっている。その各区間において、活性水を活性水噴霧ノズル１２ａ，１２ｂ，１２ｃ，１２ｄから少量ずつ複数回噴霧することで、連続的にＯＨラジカルを生成し、ダイオキシン等の有機物を分解する。また、少量噴霧することにより、低温の排ガスであっても蒸発できない活性水が残ることを可能な限り防ぎ、さらに上昇および下降方向に順次複数段噴霧することにより、蒸発できなかった活性水を下面部に速やかに落下させ、蒸発できずに残った活性水は排水通路２３１、排水穴２３２を通じ、排水タンク２４内に回収することができる。
【００２２】
実施の形態９．
以下、本発明の実施の形態９を図１０に基づいて説明する。図１０は本発明の実施の形態９における排ガス通路とその上流側に設置したオゾン化ガス噴霧装置、およびその下流部に複数設置した過酸化水素噴霧部および排水穴を示す図である。
図１０において、２５はオゾン化ガス噴霧ノズル、２６ａ、２６ｂ、２６ｃ、２６ｄは過酸化水素噴霧ノズルである。その他の符号は、図１および図９と同じである。
【００２３】
作用について説明する。本実施の形態では、排ガス２２が流れる排ガス通路１０内の最上流部に、オゾン化ガス噴霧ノズル２５によってオゾン化ガスを噴霧し、その下流部に所定の間隔で過酸化水素噴霧ノズル２６ａ、２６ｂ、２６ｃ、２６ｄを設け、これらによって過酸化水素を噴霧する。過酸化水素はオゾンと反応してＯＨラジカルを生成し、ダイオキシン等の有機物を分解するが、本実施の形態のように過酸化水素を分散して排ガス通路１０内に噴霧することにより、ＯＨラジカルを必要量のみ生成することができ、これによりＯＨラジカルの自己分解が少なくなり、効果的にダイオキシン等の有機物を分解することができる。
なお、オゾン化ガスは高温で自己分解するが、２５０℃の雰囲気では５秒以内では、ほとんど分解しないことが分かっており、排ガスを２５０℃以下に保つことによりオゾンの自己分解がなくなり、必要最小限のオゾンで効果的にダイオキシン等の有機物を分解する。
さらに、実施の形態１で説明したように、過酸化水素の噴霧を空気との二流体噴霧にすることにより、過酸化水素を微粒化し、オゾン化ガスとの接触が増し、ＯＨラジカルを多量に生成することができる。
さらに、実施の形態２で説明したように、過酸化水素を、超音波振動を使って霧化することにより、過酸化水素を微粒化し、オゾン化ガスとの接触が増し、ＯＨラジカルを多量に生成することができる。
さらに、実施の形態３で説明したように、過酸化水素を加熱し微粒子化して噴霧することにより、過酸化水素の活性が増し、ＯＨラジカルを多量に生成することができる。
さらに、実施の形態４または５で説明したように、過酸化水素を加熱し水蒸気を蒸発させ過酸化水素を濃縮して噴霧することにより、過酸化水素の活性が増し、ＯＨラジカルを多量に生成することができる。
なお、過酸化水素を加熱するとともに、これとともに噴霧される空気も加熱することで、過酸化水素の噴霧ガスが一層高温となり、過酸化水素の活性が増し、ＯＨラジカルを多量に生成することができる。
また、排ガス通路の下面部に蒸発できずに残った活性水は排水穴２３２を通じて排水され、排水タンク２４内に回収することができる。
【００２４】
実施の形態１０．
以下、本発明の実施の形態１０を図１１に基づいて説明する。図１１は本発明の実施の形態１０における過酸化水素供給量制御、オゾン化ガス発生量制御および冷却水供給量制御のフローを示す図である。
図１１において、３０は排ガス通路、３１は温度検出器、３２は流量検出器、３３は排ガス温度測定手段、３４は排ガス流量測定手段、３５はオゾン量・過酸化水素量決定手段、３６はダイオキシン類分解演算モデルが収納されたデータベース、３７はオゾン発生器、３８はオゾン量検出器、３９はオゾン量測定手段、４０は過酸化水素供給装置、４１は過酸化水素量検出器、４２は過酸化水素量測定手段、４３は混合反応器、４４は排ガス温度設定値、４５は冷却水量決定手段、４６は冷却水量制御器、４７は活性水噴霧ノズルである。
【００２５】
作用について説明する。温度検出器３１の検出信号を入力とする排ガス温度測定手段３３、および流量検出器３２の検出信号を入力とする排ガス量測定手段３４により、排ガス通路３０中の排ガス温度および流量が求められる。これらの出力（排ガス温度、排ガス流量）はオゾン量・過酸化水素量決定手段３５に入力される。オゾン量・過酸化水素量決定手段３５はデータベース３６に収納されたダイオキシン類分解演算モデルを参照し、必要なオゾン量および過酸化水素量を決定する。データベース３６内のダイオキシン類分解演算モデルは、過去の実験および解析結果に基づき構築された計算モデルで、排ガス温度や排ガス量などの条件からダイオキシン類分解を高精度に予測することができる。
オゾン化ガス発生量制御については、オゾン量・過酸化水素量決定手段３５で得られた目標値が、実際のオゾン発生量の測定値（オゾン量検出器３８の測定値に基くオゾン量測定手段３９の出力）と比較され、その結果がオゾン発生器３７内の制御装置に入力され、オゾン化ガス発生量を制御する。
過酸化水素供給量制御については、オゾン量・過酸化水素量決定手段３５で得られた目標値が、実際の過酸化水素供給量の測定値（過酸化水素量検出器４１の測定値に基く過酸化水素量測定手段４２の出力）と比較され、その結果が過酸化水素供給装置４０に入力され、過酸化水素供給量を制御する。
オゾン発生器３７で発生されたオゾン化ガスおよび過酸化水素供給装置４０から供給された過酸化水素は、前記の実施の形態で説明したように、混合反応器４３で混合され、活性水を生成する。
排ガス温度制御については、排ガス温度測定手段３３の出力が排ガス温度設定値４４と比較され、その結果を冷却水量決定手段４５に入力、冷却水量決定手段４５の結果が冷却水量制御器４６に入力され、冷却水量を制御する。
混合反応器４３で生成された活性水および冷却水量制御器４６で調整された冷却水は、噴霧ノズルにて混合され、排ガス通路３０内に活性水噴霧ノズル４７により噴霧される。
【００２６】
なお、前記の実施の形態１〜１０では、焼却炉の排ガス通路内に活性水を供給して排ガスの冷却過程でダイオキシン類の分解を行う例を説明したが、本発明は焼却炉の排ガスに限ることなく、灰溶融炉、金属精錬炉、アルミ溶解炉、焼成炉、電気炉などの排ガスの分解に適用し、前記の実施の形態１〜１０と同様にダイオキシン類はもちろんのこと、その他有機物の分解も可能なことは言及するまでもない。
【００２７】
【発明の効果】
請求項１の発明は、オゾン化ガス、過酸化水素および水を含む活性水を、排ガス通路を流れる排ガスと接触させ、前記排ガスに含まれる被処理成分を分解する排ガス処理方法において、前記活性水が、前記オゾン化ガスの導入された混合反応器に前記過酸化水素を噴霧し、ＯＨラジカル生成反応を促進し、続いて前記水と混合して得られたものであることを特徴とする排ガス処理方法であるので、オゾン化ガスと過酸化水素の反応によるＯＨラジカル生成反応が促進され、ＯＨラジカルが高効率に生成され、所定の被処理成分の分解率を得るための供給オゾン化ガス量、過酸化水素量の低減が可能となった。この結果、オゾン発生器の小型化が可能であり、設備コスト、ランニングコストの低減が可能になった。
【００２８】
請求項２の発明は、過酸化水素に超音波振動を施した後、混合反応器に噴霧することを特徴とする請求項１に記載の排ガス処理方法であるので、混合反応器内で過酸化水素がオゾン化ガスと効率よく混合され、ＯＨラジカル生成反応が促進され、ＯＨラジカルの発生量は増大する。従って、所定の被処理成分の分解率を得るための供給オゾン化ガス量、過酸化水素量の低減が可能となった。この結果、オゾン発生器の小型化が可能であり、設備コスト、ランニングコストの低減が可能になった。
【００２９】
請求項３の発明は、過酸化水素を加熱した後、混合反応器に噴霧することを特徴とする請求項１に記載の排ガス処理方法であるので、過酸化水素の活性が高くなり、オゾン化ガスと混合したとき、ＯＨラジカルが多量に発生する。従って、所定の被処理成分の分解率を得るための供給オゾン化ガス量、過酸化水素量の低減が可能となった。この結果、オゾン発生器の小型化が可能であり、設備コスト、ランニングコストの低減が可能になった。
【００３０】
請求項４の発明は、過酸化水素を加熱蒸気とした後、混合反応器に噴霧することを特徴とする請求項３に記載の排ガス処理方法であるので、過酸化水素の活性が高くなり、オゾン化ガスと混合したとき、ＯＨラジカルが多量に発生する。従って、所定の被処理成分の分解率を得るための供給オゾン化ガス量、過酸化水素量の低減が可能となった。この結果、オゾン発生器の小型化が可能であり、設備コスト、ランニングコストの低減が可能になった。
【００３１】
請求項５の発明は、過酸化水素を濃縮するとともに加熱蒸気とした後、混合反応器に噴霧することを特徴とする請求項４に記載の排ガス処理方法であるので、過酸化水素の活性が高くなり、オゾン化ガスと混合したとき、ＯＨラジカルが多量に発生する。従って、所定の被処理成分の分解率を得るための供給オゾン化ガス量、過酸化水素量の低減が可能となった。この結果、オゾン発生器の小型化が可能であり、設備コスト、ランニングコストの低減が可能になった。
【００３２】
請求項６の発明は、活性水を排ガスと接触させた後に、その下流の排ガス通路にオゾン分解処理手段を設け、前記排ガス通路に残存するオゾンを分解することを特徴とする請求項１に記載の排ガス処理方法であるので、活性水との接触後の排ガス中に残存する微量のオゾン化ガスが排ガス通路を介して大気に放出されることを防止し、なおかつオゾン化ガスが排ガス通路を腐食することも防止することができる。
【００３３】
請求項７の発明は、オゾン分解処理手段が、活性炭微粒子を排ガス通路に噴霧する手段であることを特徴とする請求項６に記載の排ガス処理方法であるので、活性水との接触後の排ガス中に残存する微量のオゾン化ガスが排ガス通路を介して大気に放出されることを防止し、なおかつオゾン化ガスが排ガス通路を腐食することも防止することができる。
【００３４】
請求項８の発明は、オゾン分解処理手段が、排ガスを活性炭微粒子が充填された充填塔に通過させる手段であることを特徴とする請求項６に記載の排ガス処理方法であるので、活性水との接触後の排ガス中に残存する微量のオゾン化ガスが活性炭微粒子に吸着分解除去され、排ガス通路を介して大気に放出されることを防止し、なおかつオゾン化ガスが排ガス通路を腐食することも防止することができる。
【００３５】
請求項９の発明は、活性水を排ガスと接触させた後に、その下流の排ガス通路にアンモニア水を噴霧しているので、排ガスに含まれる窒素酸化物が還元され窒素ガスとなり、窒素酸化物を低減することができる。従って、有害な窒素酸化物を大気中に放出することがない。
【００３６】
請求項１０の発明は、排ガスが上昇および下降方向に順次流れるように排ガス通路を構成し、前記上昇および下降区間においてそれぞれ活性水が前記排ガスと接触するようにするとともに、前記排ガス通路の活性水の残余を排出可能にしたことを特徴とする請求項１に記載の排ガス処理方法であるので、被処理物質を連続的に生成したＯＨラジカルで分解することになり、したがって、活性水の使用量を低減し、排ガスが低温であっても活性水が残ることを可能な限り防ぐことができる、また、蒸発できなかった活性水を排ガス通路の下面部に速やかに落下させ排水穴を通じて排水できることから、排ガス通路内での活性水が凝縮せず、排ガス通路を封鎖をすることがない。
【００３７】
請求項１１の発明は、排ガス通路において排ガスとオゾン化ガスとを接触させ、続いてその下流の排ガス通路内に排ガス流れ方向に対し所定の間隔で過酸化水素を噴霧することにより、前記排ガスに含まれる被処理成分を分解することを特徴とする排ガス処理方法であるので、ＯＨラジカルの生成が分散化し、高濃度のＯＨラジカルが存在することにより自己分解が少なくなり、効果的に被処理成分の分解が可能になった。また、排ガス通路をシンプルにすることができることから、排ガス通路内での活性水が凝縮せず、排ガス通路を封鎖をすることがない。
【００３８】
請求項１２の発明は、オゾン化ガスを供給する排ガス通路内の排ガスの温度を２５０℃以下に制御することを特徴とする請求項１１に記載の排ガス処理方法であるので、オゾン化ガスが自己分解することがない。すなわち、２５０℃以下の雰囲気において、オゾン化ガスは５秒以内ではほとんど分解しないことが分かっており、排ガスを２５０℃以下に保つことによりオゾン化ガスの自己分解がなくなり、必要最小限のオゾンで効果的に被処理成分を分解することができるようになった。
【００３９】
請求項１３の発明は、過酸化水素を空気とともに排ガス通路内に噴霧することを特徴とする請求項１１に記載の排ガス処理方法であるので、過酸化水素を微粒化することができ、オゾン化ガスとの接触が増し、ＯＨラジカルを多量に生成することができ、必要最小限の過酸化水素で、被処理成分を分解することができるようになった。
【００４０】
請求項１４の発明は、過酸化水素に超音波振動を施した後、排ガス通路内に噴霧することを特徴とする請求項１１に記載の排ガス処理方法であるので、過酸化水素を微粒化することができ、オゾン化ガスとの接触が増し、ＯＨラジカルを多量に生成することができ、必要最小限の過酸化水素で、被処理成分を分解することができるようになった。
【００４１】
請求項１５の発明は、過酸化水素を加熱した後、排ガス通路内に噴霧することを特徴とする請求項１１に記載の排ガス処理方法であるので、過酸化水素の活性が増し、ＯＨラジカルを多量に生成することができ、必要最小限の過酸化水素で、被処理成分を分解することができるようになった。
【００４２】
請求項１６の発明は、過酸化水素に含まれる水分を加熱蒸発させ高濃度化した後、排ガス通路内に噴霧することを特徴とする請求項１１に記載の排ガス処理方法であるので、過酸化水素の活性が増し、ＯＨラジカルを多量に生成することができ、必要最小限の過酸化水素で、被処理成分を分解することができるようになった。
【００４３】
請求項１７の発明は、過酸化水素および空気を加熱して排ガス通路内に噴霧することを特徴とする請求項１３に記載の排ガス処理方法であるので、過酸化水素の活性が増し、ＯＨラジカルを多量に生成することができ、必要最小限の過酸化水素で、被処理成分を分解することができるようになった。
【００４４】
請求項１８の発明は、排ガス温度測定手段、排ガス量測定手段、オゾン量・過酸化水素量決定手段、オゾン発生器、過酸化水素供給装置、混合反応器および活性水供給手段を備え、前記排ガス温度測定手段により排ガス通路を流れる排ガス温度を測定するとともに前記排ガス量測定手段により前記排ガス通路内における排ガス流量を測定し、これらの測定結果に基づき、前記オゾン量・過酸化水素量決定手段が、被処理成分の分解に必要なオゾンおよび過酸化水素量を決定し、この決定された量に基いて前記オゾン発生器および過酸化水素供給装置が前記混合反応器内にオゾン化ガスおよび過酸化水素を導入し、ここで、前記過酸化水素が前記オゾン化ガスの導入された混合反応器に噴霧され、続いて水と混合することにより活性水を得、この活性水を、前記活性水供給手段により排ガス通路を流れる排ガスと接触させ、前記排ガスに含まれる被処理成分を分解するようにした、請求項１に記載の方法を行うための排ガス処理装置であるので、オゾン化ガスと過酸化水素の反応によるＯＨラジカル生成反応が促進され、ＯＨラジカルが高効率に生成され、所定の被処理成分の分解率を得るための供給オゾン化ガス量、過酸化水素量の低減が可能となった。この結果、オゾン発生器の小型化が可能であり、設備コスト、ランニングコストの低減が可能になった。
【００４５】
請求項１９の発明は、排ガス処理装置が冷却水量決定手段および冷却水量制御器をさらに備え、排ガス温度測定手段により測定された排ガス通路を流れる排ガス温度が、排ガス温度設定値よりも高い場合、冷却水量決定手段により決定された量の冷却水が、排ガス通路内に導入され温度制御を行うことを特徴とする請求項１８に記載の排ガス処理装置であるので、排ガス温度を設定値に等しくなるよう制御することができるようになり、必要かつ最小限のオゾン化ガス量および過酸化水素量の供給が可能になった。
【図面の簡単な説明】
【図１】本発明の実施の形態１における活性水製造装置と活性水供給部を示す図である。
【図２】本発明の実施の形態１における、混合反応器内の滞留時間と残存オゾン率およびＯＨラジカル濃度との関係を示す図である。
【図３】本発明の実施の形態２における活性水製造装置と活性水供給部を示す図である。
【図４】本発明の実施の形態３における活性水製造装置と活性水供給部を示す図である。
【図５】本発明の実施の形態４における活性水製造装置と活性水供給部を示す図である。
【図６】本発明の実施の形態５における活性水製造装置と活性水供給部を示す図である。
【図７】本発明の実施の形態６における活性水噴霧装置とオゾン分解処理装置を備えた焼却炉システムを示す図である。
【図８】本発明の実施の形態７における活性水噴霧装置とアンモニア水供給装置を備えた焼却炉システムを示す図である。
【図９】本発明の実施の形態８における排ガス通路と複数設置した活性水噴霧部および排水穴を示す図である。
【図１０】本発明の実施の形態９における排ガス通路とその上流側に設置したオゾン化ガス噴霧装置、およびその下流部に複数設置した過酸化水素噴霧部および排水穴を示す図である。
【図１１】本発明の実施の形態１０における過酸化水素供給量制御、オゾン化ガス発生量制御および冷却水供給量制御のフローを示す図である。
【図１２】従来の排ガス処理装置の概略構成図である。
【図１３】従来の排ガス処理装置に用いられるオゾン含有水製造装置の概略構成図である。
【符号の説明】
１　活性水生成装置、１ａ　オゾン発生装置、１ｂ　冷却水供給ポンプ、１ｃ　空気供給装置、１ｄ　反応混合器、１ｅ　過酸化水素供給装置、１ｆ　　過酸化水素用逆止弁、１ｇ　オゾン化ガス用逆止弁、１ｈ　過酸化水素噴霧ノズル、１ｉ　空気供給配管、１ｊ　過酸化水素供給配管、１ｋ　超音波発生装置、１ｍ　過酸化水素微粒子化装置、１ｎ　空気供給装置、１ｏ　活性水ヒーター、１ｐ　加熱蒸気供給装置、１ｑ　逆止弁、１ｒ　圧力弁、１ｓ　水蒸気排出管、２　活性水用配管、１０　排ガス通路、１２　活性水噴霧ノズル、１７　冷却水配管、２０　オゾン分解処理手段、２１　アンモニア水供給装置、２１ａ　アンモニア水噴霧装置、２２　排ガス、２３１　排水通路、２３２　排水穴、２４　排水タンク、２５　オゾン化ガス噴霧ノズル、２６　過酸化水素噴霧ノズル、３０　排ガス通路、３１　温度検出器、３２　流量検出器、３３　排ガス温度測定手段、３４　排ガス量測定手段、３５　オゾン量・過酸化水素量決定手段、　３６　　データベース、３７　オゾン発生器、３８　オゾン量検出器、３９　　オゾン量測定手段、４０　過酸化水素供給装置、４１　過酸化水素量検出器、　４２　過酸化水素量測定手段、４３　混合反応器、４４　排ガス温度設定値、４５　冷却水量決定手段、４６　冷却水量制御器、４７　活性水噴霧ノズル。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an exhaust gas treatment method and an apparatus therefor, and more specifically, can generate OH radicals with high efficiency, can suppress supply amounts of ozonized gas and hydrogen peroxide, and reduce cost. The present invention relates to an exhaust gas treatment method capable of lowering the temperature and an apparatus therefor.
[0002]
[Prior art]
FIG. 12 is a schematic configuration diagram of an exhaust gas treatment method and apparatus capable of decomposing dioxins in exhaust gas from an incinerator disclosed in, for example, JP-A-2000-185217. In FIG. 12, 59 is an incinerator, 60 is an exhaust gas passage, 61 is a cooling tower, 62 is an active water supply unit composed of a two-fluid spray nozzle, 63 is an electric dust collector, 64 is an induction blower, 65 is a chimney, 51 Is an ozone-containing water producing apparatus, 52 is an ozonized gas supply pipe, and 67 is an ozone-containing water supply pipe. FIG. 13 is a flow chart of the apparatus for producing ozone-containing water. In FIG. 13, 51a is a water pump, 51b and 51c are check valves, 51d is an ozone generator, 51e is an ejector, 51f is a gas-liquid mixer, and 51g is a hydrogen peroxide supply device.
Next, the operation will be described. In FIG. 12, when combustible waste and the like are incinerated in the incinerator 59, a combustion gas of about 850 ° C. is generated. This combustion gas is cooled to 650 ° C. or lower through a boiler or the like (not shown), and is then drawn into the cooling tower 61 by the draft blower 64. In the cooling tower 61, active water composed of ozone-containing water, hydrogen peroxide, and ozonized gas containing ozone in cooling water is supplied from an active water supply unit 62 attached to the cooling tower to combustion gas (also referred to as exhaust gas). The combustion gas is rapidly cooled to about 200 ° C. After the cooled combustion gas is subjected to dust removal by the electric precipitator 63, the combustion gas is exhausted to the atmosphere from the chimney 65 through the induction blower 64.
In FIG. 13, the activated water is an ozonized gas (mixed gas of ozone and air or oxygen) generated by an ozone generator 51 d using air or oxygen as a raw material, and the ozonized gas is subjected to a suction action of an ejector 51 e and gas-liquid It is composed of ozone-containing water obtained by being dissolved in cold water by the mixer 51f, and hydrogen peroxide supplied from the hydrogen peroxide supply device 51g. The activated water is sprayed and supplied to the exhaust gas in the cooling tower from the activated water supply unit in the form of particles.
The conventional exhaust gas treatment apparatus is configured as described above. In the cooling tower, active water as a spray fluid is supplied in particulate form to combustion gas (also referred to as exhaust gas) to perform rapid cooling. In addition, OH radicals having strong oxidizing power are generated by a catalytic chemical reaction between ozonized gas and hydrogen peroxide in activated water and a thermal decomposition reaction of ozonized gas. A feature of this conventional exhaust gas treatment apparatus is that the generated OH radicals react with dioxins in the combustion gas to decompose precursor substances of dioxins and decompose dioxins. Further, the combustion gas at about 200 ° C. after the decomposition of dioxins is exhausted from the chimney after most of the dust in the combustion gas is collected by an electric dust collector. As a result, dioxins in the exhaust gas discharged from the chimney can be reduced, and dioxins in dust collected by the electric dust collector can be significantly reduced.
[0003]
[Problems to be solved by the invention]
The conventional exhaust gas treatment apparatus is configured as shown in FIGS. 12 and 13, and its operation is to supply active water in particulate form to combustion gas (hereinafter referred to as exhaust gas), and ozone-containing water contained in active water. OH radicals, which are thought to have a strong effect on the decomposition of dioxins, are efficiently generated in large amounts by chemical and thermal decomposition reactions by using ozonized gas and hydrogen peroxide to decompose dioxins. At this time, it is important to efficiently react OH radicals with dioxins in exhaust gas. However, it has been found that in the conventional apparatus, the generation efficiency of OH radicals due to the reaction between the ozonized gas and hydrogen peroxide in the cooling tower is not so high. For this reason, in order to decompose dioxins in exhaust gas, it was necessary to supply a large amount of ozonized gas and hydrogen peroxide.
[0004]
Therefore, an object of the present invention is to solve the above problems, and it is possible to generate OH radicals with high efficiency, to suppress the supply of ozonized gas and hydrogen peroxide, and to reduce the cost. It is an object of the present invention to provide a method for treating exhaust gas and a device therefor.
[0005]
[Means for Solving the Problems]
An invention according to claim 1 is an exhaust gas treatment method in which activated water containing ozonized gas, hydrogen peroxide and water is brought into contact with exhaust gas flowing through an exhaust gas passage to decompose components to be treated contained in the exhaust gas.
The activated water is obtained by spraying the hydrogen peroxide into a mixing reactor into which the ozonized gas is introduced, promoting an OH radical generation reaction, and subsequently mixing the water with the water. Is an exhaust gas treatment method.
The invention according to claim 2 is the exhaust gas treatment method according to claim 1, wherein the hydrogen peroxide is subjected to ultrasonic vibration and then sprayed into a mixing reactor.
The invention according to claim 3 is the exhaust gas treatment method according to claim 1, wherein the hydrogen peroxide is heated and then sprayed into a mixing reactor.
According to a fourth aspect of the present invention, there is provided the exhaust gas treatment method according to the third aspect, wherein hydrogen peroxide is converted into heated steam and then sprayed into a mixing reactor.
The invention according to claim 5 is the exhaust gas treatment method according to claim 4, wherein the hydrogen peroxide is concentrated, converted into heated steam, and then sprayed into a mixing reactor.
The invention according to claim 6 is characterized in that, after the activated water is brought into contact with the exhaust gas, an ozone decomposition treatment means is provided in an exhaust gas passage downstream of the activated water to decompose ozone remaining in the exhaust gas passage. Exhaust gas treatment method.
The invention according to claim 7 is the exhaust gas treatment method according to claim 6, wherein the ozone decomposition treatment means is means for spraying activated carbon fine particles into an exhaust gas passage.
The invention of claim 8 is the exhaust gas treatment method according to claim 6, wherein the ozonolysis treatment means is means for passing the exhaust gas to a packed tower filled with activated carbon fine particles.
The invention of claim 9 is characterized in that, after the activated water is brought into contact with the exhaust gas, ammonia water is sprayed into an exhaust gas passage downstream of the activated water to reduce nitrogen oxides contained in the exhaust gas. Exhaust gas treatment method.
According to a tenth aspect of the present invention, the exhaust gas passage is formed so that the exhaust gas flows sequentially in the ascending and descending directions, and the activated water is brought into contact with the exhaust gas in the ascending and descending sections, respectively. The exhaust gas treatment method according to claim 1, wherein a residue of the waste gas can be discharged.
The invention of claim 11 provides the exhaust gas by contacting the exhaust gas with the ozonized gas in the exhaust gas passage, and subsequently spraying hydrogen peroxide into the exhaust gas passage downstream thereof at predetermined intervals in the exhaust gas flow direction. An exhaust gas treatment method characterized by decomposing components to be contained.
According to a twelfth aspect of the present invention, there is provided the exhaust gas treatment method according to the eleventh aspect, wherein the temperature of the exhaust gas in the exhaust gas passage for supplying the ozonized gas is controlled to 250 ° C. or less.
A thirteenth aspect of the present invention is the exhaust gas treatment method according to the eleventh aspect, wherein hydrogen peroxide is sprayed into the exhaust gas passage together with air.
The invention according to claim 14 is the exhaust gas treatment method according to claim 11, wherein the hydrogen peroxide is subjected to ultrasonic vibration and then sprayed into an exhaust gas passage.
The invention according to claim 15 is the exhaust gas treatment method according to claim 11, wherein the hydrogen peroxide is heated and then sprayed into an exhaust gas passage.
The invention according to claim 16 is the exhaust gas treatment method according to claim 11, wherein the water contained in the hydrogen peroxide is heated and evaporated to increase its concentration, and then sprayed into an exhaust gas passage.
The invention according to claim 17 is the exhaust gas treatment method according to claim 13, wherein the hydrogen peroxide and the air are heated and sprayed into the exhaust gas passage.
The invention according to claim 18 comprises exhaust gas temperature measuring means, exhaust gas amount measuring means, ozone amount / hydrogen peroxide amount determining means, ozone generator, hydrogen peroxide supply device, mixing reactor and active water supply means, The temperature of the exhaust gas flowing through the exhaust gas passage is measured by the temperature measuring means and the flow rate of the exhaust gas in the exhaust gas passage is measured by the exhaust gas amount measuring means, and the ozone amount / hydrogen peroxide amount determining means is determined based on the measurement results. The amounts of ozone and hydrogen peroxide required to decompose the components to be treated are determined, and based on the determined amounts, the ozone generator and the hydrogen peroxide supply device enter the ozonized gas and hydrogen peroxide in the mixing reactor. Wherein the hydrogen peroxide is sprayed into a mixing reactor into which the ozonized gas has been introduced, and subsequently mixed with water to obtain activated water. 2. An exhaust gas treatment apparatus for performing the method according to claim 1, wherein the activated water is brought into contact with exhaust gas flowing through an exhaust gas passage by the activated water supply means to decompose components to be treated contained in the exhaust gas. .
The exhaust gas treatment apparatus may further include a cooling water amount determination unit and a cooling water amount controller, and when the temperature of the exhaust gas flowing through the exhaust gas passage measured by the exhaust gas temperature measurement unit is higher than an exhaust gas temperature set value, 19. The exhaust gas treatment apparatus according to claim 18, wherein the amount of cooling water determined by the water amount determining means is introduced into the exhaust gas passage to perform temperature control.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1 FIG.
Hereinafter, Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an activated water production device and an activated water supply unit according to Embodiment 1 of the present invention.
In FIG. 1, 1 is an activated water generator, 1a is an ozone generator, 1b is a water supply pump, 1c is an air supply device, 1d is a mixing reactor, 1e is a hydrogen peroxide supply device, and 1f is an inverse for hydrogen peroxide. Stop valve, 1 g is a check valve for ozonized gas, 1 h is a hydrogen peroxide spray nozzle, 1 i is an air supply pipe, 1 j is a hydrogen peroxide supply pipe, 2 is a pipe for active water, 12 is an active water spray nozzle, 17 Is a water pipe for activated water.
[0007]
The operation will be described. In the present embodiment, the ozonized gas generated by the ozone generator 1a is introduced into the cylindrical mixing reactor 1d via the ozonized gas check valve 1g. Subsequently, hydrogen peroxide supplied from the hydrogen peroxide supply device 1e is introduced into the mixing reactor 1d via the hydrogen peroxide prevention valve 1f and the hydrogen peroxide supply pipe 1j. At this time, the introduction of hydrogen peroxide is performed by spraying from a hydrogen peroxide spray nozzle 1h provided in the mixing reactor 1d. That is, the hydrogen peroxide is sprayed by the hydrogen peroxide spray nozzle 1h together with the air (air) supplied from the air supply device 1c and the air supply pipe 1i. At this time, since the hydrogen peroxide is formed into fine particles, the hydrogen peroxide is efficiently mixed with the ozonized gas, and a large amount of OH radicals is generated. The ozonized gas containing a large amount of OH radicals is guided to the active water spray nozzle 12 which is an active water supply unit, mixed with water supplied from the water supply pump 1b and the water pipe 17 for active water, becomes active water, and emits exhaust gas. Sprayed inside.
FIG. 2 is a diagram showing the relationship between the residence time in the mixing reactor, the residual ozone ratio, and the OH radical concentration in the present embodiment. The OH radical concentration was estimated from the experimental results of the residual ozone rate. As a comparison, a conventional method (in which hydrogen peroxide was introduced together with water without spraying into the mixing reactor) is also shown. From the results shown in FIG. 2, it can be seen that in the conventional method, the ozonized gas and the hydrogen peroxide did not sufficiently contact in the mixed reactor, so that a large amount of the ozonized gas remained even when the residence time was extended. I understood. From the results, it is inferred that the generation efficiency of the OH radical is not high and the concentration is low. However, in the present embodiment, since the ozonized gas and the hydrogen peroxide sufficiently come into contact in the mixed reactor, the remaining ozone is small, and therefore, the generation efficiency of OH radicals is high and a large amount of OH radicals is generated. It is estimated that there is.
[0008]
Embodiment 2 FIG.
Hereinafter, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a diagram showing an activated water producing apparatus and an activated water supply unit according to Embodiment 2 of the present invention.
In FIG. 3, 1k is an ultrasonic generator, 1m is a hydrogen peroxide fine particle generator, and 1n is an air supply device. Other symbols are the same as those in FIG.
[0009]
The operation will be described. Also in the present embodiment, as in Embodiment 1, the ozonized gas is introduced into the cylindrical mixing reactor 1d, and simultaneously, hydrogen peroxide and air are sprayed into the mixing reactor in two fluids. The present embodiment is characterized in that a hydrogen peroxide fine particle generator 1m is provided. Ultrasonic vibration is given to hydrogen peroxide in advance by an ultrasonic generator 1k, and air is introduced into the hydrogen peroxide from an air supply device 1n. By doing so, the hydrogen peroxide is atomized, guided to the hydrogen peroxide spray nozzle 1h in the mixing reactor, and sprayed into the mixing reactor 1d with two fluids. At this time, since the hydrogen peroxide is further reduced to fine particles, the hydrogen peroxide is efficiently mixed with the ozonized gas, and the amount of generated OH radicals increases. The ozonized gas containing a large amount of OH radicals is guided to the active water spray nozzle 12 which is an active water supply unit, mixed with water supplied from the water supply pump 1b and the water pipe 17 for active water, becomes active water, and emits exhaust gas. Sprayed inside.
[0010]
Embodiment 3 FIG.
Hereinafter, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a diagram showing an activated water production device and an activated water supply unit according to Embodiment 3 of the present invention.
In FIG. 4, reference numeral 1o denotes an activated water heater. Other symbols are the same as those in FIG.
[0011]
The operation will be described. Also in the present embodiment, as in Embodiment 1, the ozonized gas is introduced into the cylindrical mixing reactor 1d, and simultaneously, hydrogen peroxide and air are sprayed into the mixing reactor in two fluids. In the present embodiment, the hydrogen peroxide is heated to a high temperature in advance by the activated water heater 1o to increase the activity of the hydrogen peroxide, and is guided to the hydrogen peroxide spray nozzle 1h in the mixing reactor 1d, and is sprayed with two fluids. At this time, since hydrogen peroxide has high activity, a large amount of OH radicals is generated when mixed with ozonized gas. The ozonized gas containing a large amount of OH radicals is guided to the active water spray nozzle 12 which is an active water supply unit, mixed with water supplied from the water supply pump 1b and the water pipe 17 for active water, becomes active water, and emits exhaust gas. Sprayed inside.
[0012]
Embodiment 4 FIG.
Hereinafter, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a diagram showing an activated water production device and an activated water supply unit according to Embodiment 4 of the present invention.
In FIG. 5, 1p is a heating steam supply device, 1q is a check valve, and 1r is a pressure valve. Other symbols are the same as those in FIG.
[0013]
The operation will be described. Also in the present embodiment, as in Embodiment 1, the ozonized gas is introduced into the cylindrical mixing reactor 1d, and simultaneously, hydrogen peroxide and air are sprayed into the mixing reactor in two fluids. In the present embodiment, the hydrogen peroxide is heated to a high temperature in advance by the heating steam supply device 1p to increase the activity of the hydrogen peroxide as a heating steam and further to make it into a vapor, thereby improving the contact reaction characteristics with the ozonized gas. Then, the mixture is led to a hydrogen peroxide spray nozzle 1h in the mixing reactor 1d and sprayed with two fluids. At this time, since hydrogen peroxide has a high activity, a large amount of OH radicals is generated when mixed with ozonized gas. The ozonized gas containing a large amount of OH radicals is guided to the active water spray nozzle 12 which is an active water supply unit, mixed with water supplied from the water supply pump 1b and the water pipe 17 for active water, becomes active water, and emits exhaust gas. Sprayed inside.
[0014]
Embodiment 5 FIG.
Hereinafter, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a diagram showing an activated water producing apparatus and an activated water supply unit according to Embodiment 5 of the present invention.
In FIG. 6, 1s is a steam discharge pipe. Other reference numerals are the same as those in FIGS.
[0015]
The operation will be described. Also in the present embodiment, as in the fourth embodiment, an ozonized gas is introduced into a cylindrical mixing reactor 1d, and at the same time, hydrogen peroxide and air are two-fluid sprayed into the mixing reactor. In the present embodiment, hydrogen peroxide is heated to a high temperature in advance by a heating steam supply device 1p to form heated steam, and steam is evaporated to a high concentration of hydrogen peroxide by a steam discharge pipe 1s. Of the mixture, and the mixture is guided to a hydrogen peroxide spray nozzle 1h in the mixing reactor 1d, and sprayed with two fluids. At this time, since hydrogen peroxide has a high activity and a high concentration, a large amount of OH radicals is generated when mixed with the ozonized gas. The water is guided to the active water spray nozzle 12, which is an active water supply unit, mixed with water supplied from the water supply pump 1b and the water pipe 17 for active water, becomes active water, and is sprayed into exhaust gas.
[0016]
Embodiment 6 FIG.
Hereinafter, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 7 is a diagram showing an incinerator system provided with an activated water production device and an ozonolysis treatment device according to Embodiment 6 of the present invention.
In FIG. 7, reference numeral 20 denotes an ozonolysis treatment device. Other symbols are the same as those in FIGS.
[0017]
The operation will be described. In the present embodiment, ozone remaining in the downstream exhaust gas passage after activated water is supplied is decomposed by the ozone decomposition treatment device 20 installed in the exhaust gas passage after dioxin has been decomposed. The means for decomposing ozone is, for example, a method of spraying activated carbon fine particles on exhaust gas containing ozone. Alternatively, as a means, a method of passing through a packed tower filled with activated carbon particles is used.
[0018]
Embodiment 7 FIG.
Hereinafter, a seventh embodiment of the present invention will be described with reference to FIG. FIG. 8 is a diagram showing an incinerator system provided with an activated water spray device and an ammonia water supply device according to Embodiment 7 of the present invention.
In FIG. 7, reference numeral 21 denotes an ammonia water supply device, and 21a denotes an ammonia water spray device. Other symbols are the same as those in FIGS.
[0019]
The operation will be described. In the present embodiment, the ammonia water is sprayed into the exhaust gas passage by the ammonia water supply device 21 and the ammonia water spray device 21a installed in the exhaust gas passage after dioxin is decomposed, and the nitrogen oxides are reduced to nitrogen gas, which is harmful. Nitrogen oxides. As means for spraying the ammonia water, by spraying and supplying the ammonia water in the form of fine particles, the contact with the exhaust gas is increased, and the nitrogen oxides can be significantly reduced.
[0020]
Embodiment 8 FIG.
Hereinafter, an eighth embodiment of the present invention will be described with reference to FIG. FIG. 9 is a diagram showing an exhaust gas passage, a plurality of activated water spray units and drain holes according to an eighth embodiment of the present invention.
In FIG. 9, 10 is an exhaust gas passage, 12a, 12b, 12c, and 12d are activated water spray nozzles, 22 is an exhaust gas, 231 is a drain passage, 232 is a drain hole, and 24 is a drain tank. The other reference numerals are the same as those of the conventional exhaust gas treatment apparatus shown in FIGS.
[0021]
The operation will be described. In the present embodiment, the exhaust gas 22 sequentially flows in the ascending and descending directions in the exhaust gas passage 10 (corresponding to a conventional cooling tower). In each section, active water is sprayed a small number of times from the active water spray nozzles 12a, 12b, 12c, and 12d a plurality of times to continuously generate OH radicals and decompose organic substances such as dioxin. Also, by spraying a small amount, it is possible to prevent active water that cannot evaporate even with low-temperature exhaust gas from remaining as much as possible. Activated water that has been quickly dropped into the drainage portion and that has not been evaporated can be collected in the drainage tank 24 through the drainage passage 231 and the drainage hole 232.
[0022]
Embodiment 9 FIG.
Hereinafter, a ninth embodiment of the present invention will be described with reference to FIG. FIG. 10 is a diagram showing an exhaust gas passage and an ozonized gas spraying device installed upstream thereof, and a plurality of hydrogen peroxide spraying units and drain holes installed downstream thereof according to Embodiment 9 of the present invention.
In FIG. 10, 25 is an ozonized gas spray nozzle, and 26a, 26b, 26c, 26d are hydrogen peroxide spray nozzles. Other reference numerals are the same as those in FIGS.
[0023]
The operation will be described. In the present embodiment, an ozonized gas is sprayed by the ozonized gas spray nozzle 25 on the uppermost stream in the exhaust gas passage 10 through which the exhaust gas 22 flows, and the hydrogen peroxide spray nozzles 26a and 26b are sprayed at predetermined intervals on the downstream thereof. , 26c and 26d, and hydrogen peroxide is sprayed by these. Hydrogen peroxide reacts with ozone to generate OH radicals and decomposes organic substances such as dioxin. However, as in the present embodiment, hydrogen peroxide is dispersed and sprayed into the exhaust gas passage 10 to form OH radicals. Can be generated only in a required amount, whereby self-decomposition of OH radicals is reduced, and organic substances such as dioxin can be effectively decomposed.
It is known that the ozonized gas decomposes at a high temperature, but hardly decomposes in an atmosphere of 250 ° C. within 5 seconds. Organic substances such as dioxin can be effectively decomposed with limited ozone.
Further, as described in the first embodiment, by spraying hydrogen peroxide as a two-fluid spray with air, hydrogen peroxide is atomized, contact with ozonized gas is increased, and OH radicals are generated in a large amount. Can be generated.
Further, as described in Embodiment 2, by atomizing hydrogen peroxide using ultrasonic vibration, the hydrogen peroxide is atomized, the contact with the ozonized gas increases, and a large amount of OH radicals is generated. Can be generated.
Further, as described in Embodiment 3, by heating and atomizing hydrogen peroxide and spraying it, the activity of hydrogen peroxide is increased, and a large amount of OH radicals can be generated.
Further, as described in Embodiment Mode 4 or 5, by heating hydrogen peroxide, evaporating water vapor and concentrating and spraying hydrogen peroxide, the activity of hydrogen peroxide increases, and a large amount of OH radicals is generated. can do.
In addition, by heating the hydrogen peroxide and also the air sprayed therewith, the temperature of the sprayed hydrogen peroxide gas becomes even higher, the activity of the hydrogen peroxide increases, and a large amount of OH radicals can be generated. it can.
Activated water remaining without being evaporated on the lower surface of the exhaust gas passage is drained through the drain hole 232 and can be collected in the drain tank 24.
[0024]
Embodiment 10 FIG.
Hereinafter, a tenth embodiment of the present invention will be described with reference to FIG. FIG. 11 is a diagram showing a flow of hydrogen peroxide supply control, ozonized gas generation control, and cooling water supply control in the tenth embodiment of the present invention.
11, reference numeral 30 denotes an exhaust gas passage, 31 denotes a temperature detector, 32 denotes a flow detector, 33 denotes an exhaust gas temperature measuring means, 34 denotes an exhaust gas flow measuring means, 35 denotes an ozone amount / hydrogen peroxide amount determining means, and 36 denotes dioxin. A database storing the similar decomposition calculation models, 37 is an ozone generator, 38 is an ozone amount detector, 39 is an ozone amount measuring means, 40 is a hydrogen peroxide supply device, 41 is a hydrogen peroxide amount detector, and 42 is an excess amount. Hydrogen oxide amount measuring means, 43 is a mixing reactor, 44 is an exhaust gas temperature set value, 45 is a cooling water amount determining means, 46 is a cooling water amount controller, and 47 is an active water spray nozzle.
[0025]
The operation will be described. The exhaust gas temperature and flow rate in the exhaust gas passage 30 are obtained by the exhaust gas temperature measuring means 33 which receives the detection signal of the temperature detector 31 and the exhaust gas amount measuring means 34 which receives the detection signal of the flow rate detector 32 as input. These outputs (exhaust gas temperature and exhaust gas flow rate) are input to the ozone amount / hydrogen peroxide amount determining means 35. The ozone amount / hydrogen peroxide amount determining means 35 refers to the dioxin decomposition calculation model stored in the database 36 and determines the necessary ozone amount and hydrogen peroxide amount. The dioxin decomposition calculation model in the database 36 is a calculation model constructed based on past experiments and analysis results, and can predict dioxin decomposition with high accuracy from conditions such as exhaust gas temperature and exhaust gas amount.
As for the control of the amount of ozonized gas generated, the target value obtained by the ozone amount / hydrogen peroxide amount determining means 35 is the measured value of the actual amount of ozone generated (the ozone amount measuring means based on the measured value of the ozone amount detector 38). 39, and the result is input to a control device in the ozone generator 37 to control the amount of ozonized gas generated.
Regarding the control of the supply amount of hydrogen peroxide, the target value obtained by the ozone amount / hydrogen peroxide amount determination means 35 is a measured value of the actual supply amount of hydrogen peroxide (based on the measurement value of the hydrogen peroxide amount detector 41). (The output of the hydrogen peroxide amount measuring means 42), and the result is input to the hydrogen peroxide supply device 40 to control the hydrogen peroxide supply amount.
The ozonized gas generated by the ozone generator 37 and the hydrogen peroxide supplied from the hydrogen peroxide supply device 40 are mixed in the mixing reactor 43 to generate activated water as described in the above embodiment. I do.
As for the exhaust gas temperature control, the output of the exhaust gas temperature measuring means 33 is compared with the exhaust gas temperature set value 44, and the result is input to the cooling water amount determining means 45, and the result of the cooling water amount determining means 45 is input to the cooling water amount controller 46. Control the amount of cooling water.
The active water generated in the mixing reactor 43 and the cooling water adjusted by the cooling water amount controller 46 are mixed by a spray nozzle and sprayed into the exhaust gas passage 30 by an active water spray nozzle 47.
[0026]
In the first to tenth embodiments, an example has been described in which active water is supplied into an exhaust gas passage of an incinerator to decompose dioxins in a process of cooling the exhaust gas. Without limitation, the present invention is applied to the decomposition of exhaust gas from ash melting furnaces, metal refining furnaces, aluminum melting furnaces, firing furnaces, electric furnaces, and the like. Dioxins as well as the above-described Embodiments 1 to 10 and other organic substances It is needless to mention that decomposition is also possible.
[0027]
【The invention's effect】
The invention according to claim 1 is an exhaust gas treatment method in which activated water containing ozonized gas, hydrogen peroxide and water is brought into contact with exhaust gas flowing through an exhaust gas passage to decompose components to be treated contained in the exhaust gas. Wherein the exhaust gas is obtained by spraying the hydrogen peroxide into a mixing reactor into which the ozonized gas is introduced, promoting an OH radical generation reaction, and subsequently mixing the water with the water. Since it is a treatment method, an OH radical generation reaction by the reaction of ozonized gas and hydrogen peroxide is promoted, OH radicals are generated with high efficiency, and the amount of ozonized gas supplied to obtain a predetermined decomposition rate of the component to be treated Thus, the amount of hydrogen peroxide can be reduced. As a result, the size of the ozone generator can be reduced, and equipment costs and running costs can be reduced.
[0028]
The invention according to claim 2 is the exhaust gas treatment method according to claim 1, wherein ultrasonic vibration is applied to hydrogen peroxide, and then the mixture is sprayed into a mixing reactor. Hydrogen is efficiently mixed with the ozonized gas, the OH radical generation reaction is promoted, and the amount of generated OH radicals increases. Therefore, the amount of ozonized gas and the amount of hydrogen peroxide supplied to obtain a predetermined decomposition rate of the component to be treated can be reduced. As a result, the size of the ozone generator can be reduced, and equipment costs and running costs can be reduced.
[0029]
The third aspect of the present invention is the exhaust gas treatment method according to the first aspect, wherein the hydrogen peroxide is heated and then sprayed into a mixing reactor. When mixed with gas, a large amount of OH radicals is generated. Therefore, the amount of ozonized gas and the amount of hydrogen peroxide supplied to obtain a predetermined decomposition rate of the component to be treated can be reduced. As a result, the size of the ozone generator can be reduced, and equipment costs and running costs can be reduced.
[0030]
The invention according to claim 4 is the exhaust gas treatment method according to claim 3, wherein hydrogen peroxide is converted into heated steam and then sprayed into a mixing reactor, so that the activity of hydrogen peroxide increases, When mixed with ozonized gas, a large amount of OH radicals is generated. Therefore, the amount of ozonized gas and the amount of hydrogen peroxide supplied to obtain a predetermined decomposition rate of the component to be treated can be reduced. As a result, the size of the ozone generator can be reduced, and equipment costs and running costs can be reduced.
[0031]
According to a fifth aspect of the present invention, there is provided the exhaust gas treatment method according to the fourth aspect, wherein the hydrogen peroxide is concentrated and converted into heated steam, and then sprayed to a mixing reactor. When mixed with an ozonized gas, a large amount of OH radicals is generated. Therefore, the amount of ozonized gas and the amount of hydrogen peroxide supplied to obtain a predetermined decomposition rate of the component to be treated can be reduced. As a result, the size of the ozone generator can be reduced, and equipment costs and running costs can be reduced.
[0032]
The invention according to claim 6 is characterized in that, after the activated water is brought into contact with the exhaust gas, an ozone decomposition treatment means is provided in an exhaust gas passage downstream of the activated water to decompose ozone remaining in the exhaust gas passage. Exhaust gas treatment method, so that a small amount of ozonized gas remaining in the exhaust gas after contact with the activated water is prevented from being released to the atmosphere via the exhaust gas passage, and the ozonized gas corrodes the exhaust gas passage. Can also be prevented.
[0033]
The invention according to claim 7 is the exhaust gas treatment method according to claim 6, wherein the ozone decomposition treatment means is means for spraying activated carbon fine particles into an exhaust gas passage. It is possible to prevent a small amount of ozonized gas remaining therein from being released to the atmosphere via the exhaust gas passage, and also to prevent the ozonized gas from corroding the exhaust gas passage.
[0034]
The invention according to claim 8 is the exhaust gas treatment method according to claim 6, wherein the ozone decomposition treatment means is means for passing the exhaust gas to a packed tower filled with activated carbon fine particles. A small amount of ozonized gas remaining in the exhaust gas after contact with the active carbon particles is adsorbed and decomposed and removed by the activated carbon fine particles, and is prevented from being released to the atmosphere through the exhaust gas passage. Can be prevented.
[0035]
According to the ninth aspect of the present invention, after the activated water is brought into contact with the exhaust gas, the ammonia water is sprayed into the exhaust gas passage downstream of the activated water. Therefore, nitrogen oxides contained in the exhaust gas are reduced to nitrogen gas, and the nitrogen oxides are reduced. Can be reduced. Therefore, no harmful nitrogen oxides are emitted into the atmosphere.
[0036]
According to a tenth aspect of the present invention, the exhaust gas passage is formed so that the exhaust gas flows sequentially in the ascending and descending directions, and the activated water is brought into contact with the exhaust gas in the ascending and descending sections, respectively. The exhaust gas treatment method according to claim 1, characterized in that the substance to be treated is decomposed by continuously generated OH radicals, and thus the amount of active water used Activated water can be prevented from remaining even if the temperature of the exhaust gas is low, and the active water that could not evaporate can be quickly dropped on the lower surface of the exhaust gas passage and drained through the drain hole. In addition, active water in the exhaust gas passage is not condensed, and the exhaust gas passage is not blocked.
[0037]
The invention of claim 11 provides the exhaust gas by contacting the exhaust gas with the ozonized gas in the exhaust gas passage, and subsequently spraying hydrogen peroxide into the exhaust gas passage downstream thereof at predetermined intervals in the exhaust gas flow direction. Since the exhaust gas treatment method is characterized by decomposing the components to be contained, the generation of OH radicals is dispersed, and the presence of high concentrations of OH radicals reduces self-decomposition, thereby effectively reducing the components to be treated. Can be disassembled. In addition, since the exhaust gas passage can be simplified, active water in the exhaust gas passage does not condense and the exhaust gas passage is not blocked.
[0038]
According to a twelfth aspect of the present invention, in the exhaust gas treatment method according to the eleventh aspect, the temperature of the exhaust gas in the exhaust gas passage for supplying the ozonized gas is controlled to 250 ° C. or less. Does not decompose. That is, it is known that in an atmosphere of 250 ° C. or less, the ozonized gas hardly decomposes within 5 seconds. By keeping the exhaust gas at 250 ° C. or less, self-decomposition of the ozonized gas is eliminated, and the required minimum amount of ozone is used. The components to be treated can be effectively decomposed.
[0039]
According to a thirteenth aspect of the present invention, the exhaust gas treatment method according to the eleventh aspect is characterized in that hydrogen peroxide is sprayed together with air into an exhaust gas passage. The contact with the gas is increased, a large amount of OH radicals can be generated, and the component to be treated can be decomposed with the minimum necessary amount of hydrogen peroxide.
[0040]
According to a fourteenth aspect of the present invention, since the hydrogen peroxide is subjected to ultrasonic vibration and then sprayed into an exhaust gas passage, the hydrogen peroxide is atomized. As a result, the contact with the ozonized gas increased, a large amount of OH radicals could be generated, and the component to be treated could be decomposed with a minimum necessary amount of hydrogen peroxide.
[0041]
The invention according to claim 15 is the exhaust gas treatment method according to claim 11, wherein the hydrogen peroxide is heated and then sprayed into an exhaust gas passage. Therefore, the activity of hydrogen peroxide increases, and OH radicals are generated. A large amount can be produced, and the component to be treated can be decomposed with a minimum necessary amount of hydrogen peroxide.
[0042]
According to a sixteenth aspect of the present invention, there is provided the exhaust gas treatment method according to the eleventh aspect, wherein the moisture contained in the hydrogen peroxide is heated and evaporated to increase its concentration, and then sprayed into an exhaust gas passage. The activity of hydrogen is increased, a large amount of OH radicals can be generated, and the component to be treated can be decomposed with a minimum necessary amount of hydrogen peroxide.
[0043]
According to a seventeenth aspect of the present invention, the exhaust gas treatment method according to the thirteenth aspect is characterized in that hydrogen peroxide and air are heated and sprayed into an exhaust gas passage. Can be produced in a large amount, and the component to be treated can be decomposed with a minimum necessary amount of hydrogen peroxide.
[0044]
The invention according to claim 18 comprises exhaust gas temperature measuring means, exhaust gas amount measuring means, ozone amount / hydrogen peroxide amount determining means, ozone generator, hydrogen peroxide supply device, mixing reactor and active water supply means, The temperature of the exhaust gas flowing through the exhaust gas passage is measured by the temperature measuring means and the flow rate of the exhaust gas in the exhaust gas passage is measured by the exhaust gas amount measuring means, and the ozone amount / hydrogen peroxide amount determining means is determined based on the measurement results. The amounts of ozone and hydrogen peroxide required to decompose the components to be treated are determined, and based on the determined amounts, the ozone generator and the hydrogen peroxide supply device enter the ozonized gas and hydrogen peroxide in the mixing reactor. Wherein the hydrogen peroxide is sprayed into a mixing reactor into which the ozonized gas has been introduced, and subsequently mixed with water to obtain activated water. 2. An exhaust gas treatment apparatus for performing the method according to claim 1, wherein the activated water is brought into contact with exhaust gas flowing through an exhaust gas passage by the activated water supply means to decompose components to be treated contained in the exhaust gas. Therefore, the OH radical generation reaction due to the reaction between the ozonized gas and hydrogen peroxide is promoted, OH radicals are generated with high efficiency, and the amount of ozonized gas supplied to obtain a predetermined rate of decomposition of the component to be treated, hydrogen peroxide The amount can be reduced. As a result, the size of the ozone generator can be reduced, and equipment costs and running costs can be reduced.
[0045]
The exhaust gas treatment apparatus may further include a cooling water amount determination unit and a cooling water amount controller, and when the temperature of the exhaust gas flowing through the exhaust gas passage measured by the exhaust gas temperature measurement unit is higher than an exhaust gas temperature set value, 19. The exhaust gas treatment apparatus according to claim 18, wherein the amount of cooling water determined by the water amount determining means is introduced into the exhaust gas passage to perform temperature control, so that the exhaust gas temperature is set equal to a set value. It is now possible to control the supply of necessary and minimum amounts of ozonized gas and hydrogen peroxide.
[Brief description of the drawings]
FIG. 1 is a diagram showing an activated water production device and an activated water supply unit according to Embodiment 1 of the present invention.
FIG. 2 is a diagram showing a relationship between a residence time in a mixing reactor, a residual ozone ratio, and an OH radical concentration in Embodiment 1 of the present invention.
FIG. 3 is a diagram showing an activated water production device and an activated water supply unit according to a second embodiment of the present invention.
FIG. 4 is a diagram showing an activated water production device and an activated water supply unit according to a third embodiment of the present invention.
FIG. 5 is a diagram showing an activated water production device and an activated water supply unit according to a fourth embodiment of the present invention.
FIG. 6 is a diagram showing an activated water production device and an activated water supply unit according to a fifth embodiment of the present invention.
FIG. 7 is a diagram showing an incinerator system provided with an activated water spray device and an ozonolysis treatment device according to Embodiment 6 of the present invention.
FIG. 8 is a diagram showing an incinerator system including an activated water spray device and an ammonia water supply device according to a seventh embodiment of the present invention.
FIG. 9 is a diagram illustrating an exhaust gas passage, a plurality of activated water spray units and drain holes provided in an eighth embodiment of the present invention.
FIG. 10 is a diagram showing an exhaust gas passage and an ozonized gas spraying device installed upstream thereof, and a plurality of hydrogen peroxide spraying units and drain holes installed downstream thereof according to Embodiment 9 of the present invention.
FIG. 11 is a diagram showing a flow of hydrogen peroxide supply control, ozonized gas generation control, and cooling water supply control in a tenth embodiment of the present invention.
FIG. 12 is a schematic configuration diagram of a conventional exhaust gas treatment device.
FIG. 13 is a schematic configuration diagram of an ozone-containing water production device used in a conventional exhaust gas treatment device.
[Explanation of symbols]
1 activated water generator, 1a ozone generator, 1b cooling water supply pump, 1c air supply, 1d reaction mixer, 1e hydrogen peroxide supply, 1f check valve for hydrogen peroxide, 1g check for ozonized gas Valve, 1h hydrogen peroxide spray nozzle, 1i air supply pipe, 1j hydrogen peroxide supply pipe, 1k ultrasonic generator, 1m hydrogen peroxide atomizer, 1n air supply apparatus, 1o active water heater, 1p heating steam supply apparatus 1q check valve, 1r pressure valve, 1s steam discharge pipe, 2 pipe for active water, 10 exhaust gas passage, 12 spray nozzle for active water, 17 cooling water pipe, 20 ozone decomposition treatment means, 21 ammonia water supply device, 21a ammonia Water spray device, 22 exhaust gas, 231 drain passage, 232 drain hole, 24 drain tank, 25 ozonized gas spray nozzle, 26 hydrogen peroxide spray nozzle Reference Signs List 30 exhaust gas passage, 31 temperature detector, 32 flow rate detector, 33 exhaust gas temperature measuring means, 34 exhaust gas amount measuring means, 35 ozone amount / hydrogen peroxide amount determining means, 36 database, 37 ozone generator, 38 ozone amount detector , 39 ozone amount measuring means, 40 hydrogen peroxide supply device, 41 hydrogen peroxide amount detector, 42 hydrogen peroxide amount measuring means, 43 mixing reactor, 44 exhaust gas temperature set value, 45 cooling water amount determining means, 46 cooling water amount Controller, 47 Activated water spray nozzle.

Claims

In an exhaust gas treatment method in which ozonized gas, activated water containing hydrogen peroxide and water is brought into contact with exhaust gas flowing through an exhaust gas passage, and components to be treated contained in the exhaust gas are decomposed,
The activated water is obtained by spraying the hydrogen peroxide into a mixing reactor into which the ozonized gas is introduced, promoting an OH radical generation reaction, and subsequently mixing the activated water with the water. Exhaust gas treatment method.

2. The exhaust gas treatment method according to claim 1, wherein the hydrogen peroxide is subjected to ultrasonic vibration and then sprayed into a mixing reactor.

The exhaust gas treatment method according to claim 1, wherein the hydrogen peroxide is heated and then sprayed into a mixing reactor.

4. The exhaust gas treatment method according to claim 3, wherein after the hydrogen peroxide is heated, the mixture is sprayed into a mixing reactor.

The exhaust gas treatment method according to claim 4, wherein the hydrogen peroxide is concentrated and converted into heated steam, and then sprayed into a mixing reactor.

The exhaust gas treatment method according to claim 1, wherein after the activated water is brought into contact with the exhaust gas, an ozone decomposition treatment means is provided in an exhaust gas passage downstream thereof to decompose ozone remaining in the exhaust gas passage.

The exhaust gas treatment method according to claim 6, wherein the ozonolysis treatment means is means for spraying activated carbon fine particles into an exhaust gas passage.

The exhaust gas treatment method according to claim 6, wherein the ozonolysis treatment means is means for passing the exhaust gas through a packed tower filled with activated carbon fine particles.

The exhaust gas treatment method according to claim 1, wherein after the activated water is brought into contact with the exhaust gas, ammonia water is sprayed into an exhaust gas passage downstream of the activated water to reduce nitrogen oxides contained in the exhaust gas.

The exhaust gas passage is configured so that the exhaust gas sequentially flows in the ascending and descending directions, and the activated water is brought into contact with the exhaust gas in the ascending and descending sections, respectively, and the remaining of the activated water in the exhaust gas passage can be discharged. The method for treating exhaust gas according to claim 1, wherein:

The exhaust gas and the ozonized gas are brought into contact with each other in the exhaust gas passage, and then hydrogen peroxide is sprayed into the exhaust gas passage downstream thereof at predetermined intervals in the flow direction of the exhaust gas to decompose the components to be treated contained in the exhaust gas. A method for treating exhaust gas, comprising:

The exhaust gas treatment method according to claim 11, wherein the temperature of the exhaust gas in the exhaust gas passage for supplying the ozonized gas is controlled to 250C or less.

The exhaust gas treatment method according to claim 11, wherein the hydrogen peroxide is sprayed into the exhaust gas passage together with the air.

12. The exhaust gas treatment method according to claim 11, wherein the hydrogen peroxide is subjected to ultrasonic vibration and then sprayed into an exhaust gas passage.

The exhaust gas treatment method according to claim 11, wherein after heating the hydrogen peroxide, the hydrogen peroxide is sprayed into an exhaust gas passage.

12. The exhaust gas treatment method according to claim 11, wherein the moisture contained in the hydrogen peroxide is heated and evaporated to increase its concentration, and then sprayed into an exhaust gas passage.

14. The exhaust gas treatment method according to claim 13, wherein the hydrogen peroxide and the air are heated and sprayed into an exhaust gas passage.

An exhaust gas temperature measuring unit, an exhaust gas amount measuring unit, an ozone amount / hydrogen peroxide amount determining unit, an ozone generator, a hydrogen peroxide supply device, a mixing reactor and an active water supply unit are provided. While measuring the temperature of the flowing exhaust gas, the exhaust gas amount measuring means measures the exhaust gas flow rate in the exhaust gas passage, and based on the measurement results, the ozone amount / hydrogen peroxide amount determining means is required for the decomposition of the component to be treated. Ozone and hydrogen peroxide amounts are determined, and based on the determined amounts, the ozone generator and the hydrogen peroxide supply device introduce ozonized gas and hydrogen peroxide into the mixing reactor, where: The hydrogen peroxide is sprayed into a mixing reactor into which the ozonized gas has been introduced, and subsequently mixed with water to obtain active water. By the supply means into contact with the exhaust gas flowing through the exhaust gas passage and adapted to decompose the target components contained in the exhaust gas, the exhaust gas treatment apparatus for performing the method of claim 1.

The exhaust gas treatment device further includes a cooling water amount determining unit and a cooling water amount controller, and when the temperature of the exhaust gas flowing through the exhaust gas passage measured by the exhaust gas temperature measuring unit is higher than an exhaust gas temperature set value, the cooling water amount determining unit determines the temperature. 19. The exhaust gas treatment device according to claim 18, wherein an amount of cooling water is introduced into the exhaust gas passage to perform temperature control.