【０００１】
【発明の属する技術分野】
本発明は、（１）排水、食品等の液体中、（２）土壌、飛灰等の固体中の種々の有害有機物質を除去する方法に関する。
【０００２】
【従来の技術】
従来、有害化学物質を除去する方法には、（１）微生物や植物を用いた生物環境修復法、（２）燃焼法、（３）促進酸化法、（４）溶媒洗浄法等の様々な方法が提供されているが、このうち生物環境修復法は、油状汚染度が大きい場合に生物増殖阻害が起こるだけでなく、外来性生物導入のための生態系攪乱も懸念されるため使いにくく、その一方、燃焼法等の物理化学的方法はエネルギー消費が大きく、経費がかかりやすいという欠点を持つので、従来の技術より安価、効率的で、かつ環境に優しい技術の開発が絶えず求められている。本発明はこういった背景の下でなされたヒドロキシラジカル発生法を基盤とした新規技術であり、従来法より分解効率、経済効率を向上させ、かつエネルギー消費を低減できるようデザインされたものである。
【０００３】
本発明は、分解剤として主に生石灰を用いるが、生石灰を用いた従来の技術としては、まず川崎重工株式会社の「溶融飛灰のダイオキシン低減化・固化・安定化処理方法及び装置（特開平１１−９９３７１）」を挙げる必要がある。本特許では溶融飛灰に生石灰、消石灰、石灰石、粘土のうちのいずれかを加え、水でスラリー化した上で６００〜９００℃で熱処理する事を特徴としているが、過酸化水素等の酸化剤処理を加えていないため、本発明と比べ分解効率が落ちる事が、本発明の実施例で示したモデル実験から予測されるだけでなく、熱処理も本発明では室温〜１００℃の範囲であるのに対し、この特許では６００〜９００℃と高温であり、エネルギー効率が著しく劣り、その分、コスト高となる。また分解対象も溶融飛灰のみに限定され、そういった意味でも本発明とは競合しないものと判断できる。
【０００４】
株式会社荏原製作所も、また、「芳香族ハロゲン化合物の分解方法（特開平７−２６５４６１）」において、水分が５％以上ある土壌等の固体状の物質に、生石灰、消石灰等のアルカリ性物質とアルミニウム又は金属を添加、混合し、３００℃〜４５０℃に加熱する方法を提供しているが、やはり過酸化水素等の酸化剤処理を加えていないため、本発明の実施例で示したモデル実験から、本発明と比べ分解効率が落ちる事が予測されるだけでなく、熱処理も３００℃〜４５０℃と高く、エネルギー効率が悪い。また、荏原製作所は前述の特許とは別に、「固体中のダイオキシン類の分解方法（特開２０００−１９７８６７）」にて、「常温〜１００℃の温度条件下のスラリーで、硫酸第１鉄と過酸化水素水を添加するダイオキシン類分解方法」に特許請求を行っているが、残留し重金属汚染を起こしやすい難点を持つ硫酸第一鉄を用いずに、単に生石灰と過酸化水素の双方を添加し高温条件にするだけで、有機物分解能が著しく促進できる点については言及されておらず、やはり本発明とは競合しない。
【０００５】
また、油化産業株式会社は、「有害性環境汚染物質の無害化処理方法（特開２０００−３４３０５９）」において、「有害性環境汚染物質を含有する被処理物を、反応遅延性生石灰と混合する事を特徴とする有害性環境汚染物質の無害化処理方法（請求項１）」に関する権利を請求しているが、ここでもやはり、過酸化水素等の酸化剤処理と組み合わせていないだけでなく、熱処理を行っていないので、本発明の実施例で示したモデル実験から、分解効率が著しく劣る事が予測されるだけでなく、生石灰の利用に関しても特殊な処理を施した反応遅延性生石灰のみに限定しており、（本発明の実施例にて強い活性を確認した）通常の生石灰に関しては権利請求が行えていない。
【０００６】
また、山内昌氏は「多塩素化芳香族化合物の無害化処理方法（特開２００１−７９１０９）」において、多塩素化芳香族化合物を含む油に水を加えて乳化し、生石灰を加えて加熱する処理を特許請求しているが、この処理に過酸化水素のような酸化剤を加えていないため、本発明の実施例で示したモデル実験のデータから、本発明と比較し分解能が格段に落ちる事が予測されるだけでなく、「特許請求の範囲」で分解対象物を「多塩素化芳香族化合物を含む油」に限定しているので本発明とは競合しないものと考えられる。
【０００７】
また、ヒドロキシラジカルを用いた促進酸化処理に関する関連特許に関しては、三菱重工株式会社の「焼却灰の処理方法およびその装置（特開２００１−１３７８０３）」が挙げられ、「焼却炉から排出された焼却灰に含有する有害有機物質群を水と混合してスラリー化し、ヒドロキシラジカル存在下で酸化分解処理する事を特徴とする焼却灰の処理方法」に関して特許請求を行ってはいる。しかし、（ｉ）（土壌、底泥より分解しやすい）焼却灰のみを請求範囲とし、（飛灰より分解しにくく物性、生物性等も大きく異なる）土壌、底泥、液体は特許請求の対象としていない。また、それだけでなく、（ｉｉ）ヒドロキシラジカル産生手段が「中性若しくは弱アルカリ性状態（ｐＨ７〜９）で、過酸化水素、紫外線照射、触媒、オゾン曝気を組み合わせる事による」とのみ記述され、ヒドロキシラジカルを発生させる過程において、ヒドロキシラジカルの発生量が少ない弱アルカリ条件でなく、主にｐＨ９以上の強アルカリ条件で、生石灰と過酸化水素と熱処理を組み合わせる事によって、飛躍的に分解効率を高める事ができる点に関しては気付いておらず、その点において我々の本発明の独自性、新規制、有効性が主張できる。また、この三菱重工株式会社の特許は、「焼成灰をスラリー化するのにあたって焼却場の工場排水を使う」というアイデアを出してはいるが、熱水（高温）条件で用いる事に関しては言及がなく、それではヒドロキシラジカルを効率的に産生させる事は難しい。また、アルカリ条件下にするにあたって、「水酸化ナトリウム、水酸化カルシウムを使う」事に言及しているが、水酸化ナトリウムは毒劇物であり、使用リスク及び残留性の双方で問題がある。また、水酸化カルシウム（消石灰）より酸化カルシウム（生石灰）の方が有害有機物質の分解能を格段に高めるだけでなく、強アルカリ条件で生石灰を用いても、空気中の二酸化炭素等と自然に中和反応を起こし、残留性に問題が起こりにくい（すなわち環境に優しい）点に関しても三菱重工株式会社は気付いておらず、本発明は、こういった一連の問題点の改良を行ったものと位置付けられる。
【０００８】
【発明が解決しようとする課題】
排水、食品等の液体中、土壌、飛灰等の固体中の種々の有害有機物質群を、従来の方法と比較し、安価、効率的かつ低エネルギー条件で分解する技術を提供する事を目的とする。
【０００９】
【課題を解決するための手段】
上記目的を達成するため、液体、若しくは固体に水を加えスラリー状にしたものに、生石灰等のアルカリ剤と過酸化水素の双方の添加と熱処理（室温〜９８℃）を組み合わせる事を特徴とする液体中の有機物質除去方法及び除菌法を適用すればよい。また、必要なら、更に（１）オゾン、光照射、次亜塩素酸等の各種酸化処理、（２）触媒、（３）曝気、若しくは撹拌、（４）活性炭等炭化素材添加の計４処理のうちの１つ、若しくは複数を組み合わせれば更に分解能を促進させる事ができる。また、ゴミ等焼却場、火力発電所等の冷却過程で発生する熱水あるいは温泉水に、生石灰、過酸化水素等を供給し、浄化を行えるよう設計された省エネ型浄化プラントや、コンクリートミキサー車のようなスラリーを撹拌可能なタンクを設置した車両に、ボイラー等の加熱装置、生石灰等のアルカリ塩添加装置、過酸化水素等の酸化剤添加装置等を設置した移動車両プラントを用いれば、更にエネルギーを節約して環境浄化を進める事が可能である。更に、本方法を用いて部分浄化した土壌等に、生物環境修復技術をハイブリッド浄化法として組み合わせる手段も有効である。
【００１０】
【発明の実施の形態】
以下、本発明を更に詳細に説明する。有機物質を含有する排水に、生石灰と過酸化水素を混和し、室温〜１００℃の範囲（例えば７０℃程度）で熱処理する。この時、静置でもよいが撹拌若しくは曝気を行った方が良い。それだけで、生石灰処理のみの区や、過酸化水素処理だけの区や、生石灰と過酸化水素を常温インキュベートするだけの区より、格段に有機物質分解及び除菌を進める事が可能である。なお、この際、生石灰及び過酸化水素の添加割合は本発明の実施例で示した具体例を参考にして適宜調節すればよい。この反応の原理は、過酸化水素添加により発生するヒドロキシラジカルの発生効率が強アルカリ条件で高まり、それに更に熱処理を加える事によって、その効率が更に高まるためと推測される。また、ここでアルカリ剤として生石灰を用いるのは、強アルカリ状態にしても、水や空気中の二酸化炭素と反応して、消石灰を経て炭酸カルシウムに自然に中和されるので、環境中に強アルカリ状態が残留しにくい利点があると同時に、水と反応して熱を発生し、ヒドロキシラジカル分解効率も高める利点も同時に併せ持つからである。また、更に、生石灰は過酸化水素と同様、値段が安く、オゾン処理等と比べ、処理経費が安価に抑えられる利点もある。なお、酒等の液体食品中の有害物質（エストロゲン、ダイオキシン等）を分解する場合は、アルカリ剤として生石灰を用いる事は安全上適切ではなく、消石灰か胃腸薬としても用いられている水酸化マグネシウム等の安全性の高いアルカリ剤を用い、その上で健康を害さないよう過酸化水素の添加を最小限に留めるか、念のため紫外線照射を行って過酸化水素を完全分解する必要がある事は言うまでもない。なお、ここで紫外線照射を活用すれば、食品中で促進酸化が更に促進され、過酸化水素のみならず有害有機物質の分解効率も向上する事が期待される。また、これらアルカリ剤及び過酸化水素の添加は一度に大量投入するのではなく、一定の時間間隔をおいて、追加添加を繰り返す事が、作用時間全体を通してのヒドロキシラジカルの発生効率及び熱発生効率を高める上で望ましい。
【００１１】
また、本分解反応を更に促進するためには、一般に促進酸化反応で用いられている手段等を適宜、組み合わせれば良い。具体的に言えば、（１）オゾン、光照射、次亜塩素酸等の各種酸化処理、（２）触媒、（３）曝気、若しくは撹拌、（４）活性炭等炭化素材添加の計４処理のうちの１つ、若しくは複数を組み合わせる事が有効である。ただ、土壌等を処理する場合は、次亜塩素酸処理で生ずる塩素が、新たな有害物質産生に関わる可能性もあるので、その点は注意は要する。また、これらの処理を行えば、それだけ経費もかかるので、できるだけ単純なシステムで浄化を行った方がよい。そういった意味で、環境汚染物を浄化する場合は、生石灰と過酸化水素を添加して熱処理する方法が最も単純かつ有効であると考えられる。
【００１２】
これらの一連の方法を用いて、除菌が行えるだけでなく、排水、食品等の各種液体中のダイオキシン、ＰＣＢ、環境ホルモン、残留農薬、油、エストロゲン等の各種有害物質や臭気物質を除去する事も可能であり、幅広く環境中、食品中の有害有機物質処理に用いる事ができる。
【００１３】
また、この方法は液体だけでなく、土壌、底泥、飛灰、食品材料等の固体中の有害物質をも除去する事も可能である。これら、土壌、底泥、飛灰、食品材料に水を加え、土壌、底泥、飛灰の場合は主に生石灰等を、食品材料の場合は主に消石灰、水酸化マグネシウム等を加え、スラリー化して撹拌した上で、過酸化水素を加え、熱処理（常温〜１００℃）すればよい。なお、処理時間は、分解量をモニタリングしながら、数時間から、場合によれば数週間の間、続ければよい。
【００１４】
また、この一連の反応過程における熱処理（常温〜１００℃）において、ゴミ等焼却場、火力発電所、原子力発電所、地熱発電所等の（大量の熱を発生する）プラントの冷却用工場排水、あるいは温泉水を熱源として用いれば大きな省エネ効果が期待できる。より具体的に新規プラントを説明すれば、例えば７０℃以上の工場排水が流れる排水路の一定区画に、（１）一定時間おきに過酸化水素を添加する装置、（２）一定時間おきに生石灰等アルカリ剤を添加する装置（３）撹拌装置、（４）汚染物（汚染土壌、灰等）を添加する装置、（５）汚染処理物を排出する装置、の計５つを設置し、その区画の前後をフィルターで区切ればよい。そして、必要なら、このプラントに更に、（１）オゾン発生装置、（２）紫外線照射装置等の請求項３で述べた促進酸化等に関わる装置を設置すれば、更に分解効率は高まる事が期待される。なお、温泉水を用いる場合は、重曹等を主成分としたアルカリ温泉水を利用すれば、なお効率的、経済的に分解を進める事ができる事が期待されるが、せっかくの保養所のイメージを廃棄物処理で損なわないよう注意する必要があろう。
【００１５】
更に、提供したい新規プラントとして、コンクリートミキサー車のようなスラリーを撹拌可能なタンクを設置した車両に、ボイラー等の加熱装置、生石灰等のアルカリ塩添加装置、過酸化水素等の酸化剤添加装置等を設置し、汚染現場で汚染土壌・灰・底泥等を浄化できるよう設計された移動車両プラントを挙げたい。この車両に必要なら請求項３で述べたように、オゾン水発生装置、紫外線照射装置等を組み合わせれば分解効率を更に高める事が期待されよう。このようなプラントがあれば、例えば、ダイオキシンで汚染された土壌に、この改造ミキサー車を数台派遣し、数ヶ月かけてその場で分解を行わせた後に、そのまま車で走って、次の汚染場所に移る、といった浄化手法をとる事が可能となり、機動性を持たせた浄化が行える事が期待される。
【００１６】
また、この一連の浄化処理に用いる生石灰、消石灰等は一般に農業で肥料／土壌改良材として用いられているものなので、これらの一連の方法を用いて部分浄化した土壌、底泥や、この方法を用いて浄化した排水を添加した土壌等への植栽が比較的容易になる事が期待される。従って、この技術は汚染地緑化技術として使えると共に、植物自身あるいは植物の根に自然と（ゆるやかに）共生する土壌微生物群がラッカーゼ等を分泌し、残存している油状物質を分解する植物環境修復効果、微生物環境修復効果も期待できる（ハイブリッド浄化）。なお、ここで用いる植物種は、浄化対照となる汚染物質によって選択すればよい。例えば、ダイオキシンの場合は、ラッカーゼ活性が高い漆が効果的に分解する事が出光興産株式会社らにより報告されている（塩素化ダイオキシン汚染土壌または水の浄化法、特開２００１−２３２３４５）。また、この汚染土壌地で栽培した植物に油状汚染物が一定割合で蓄積する可能性も考えられるので、その際は、重金属蓄積植物を用いた植物環境修復技術のように、その栽培植物が成長後、刈り取り、産業廃棄物として処理する方法も有効であろう。また、植栽を行う上で、生石灰処理でアルカリ化した土壌等に、ピートモス等の酸性土壌改良材や堆肥を添加し中性化を早めても良いし、好アルカリ性植物を植栽してもよい。更に、請求項１〜７の方法で浄化した土壌等では土着菌の多くが死滅しているので、外来性の微生物が定着しやすくなる効果も期待される事もあり、植栽を行わずに単に有害物質分解微生物群を添加したり、各種堆肥を添加したりする微生物環境修復技術を組み合わせたハイブリッド浄化法も有効である。
【００１７】
次に、実施例にて本発明をより詳細に説明するが、本発明は下記の例のみに限定されるものではない。
【００１８】
【実施例】
滅菌超純水にレマゾール・ブリリアント・ブルーＲ（シグマ社）を加え、１５ｐｐｍの濃度になるように溶解し、モデル排水とした。本水溶液は、薄い青色を呈する。本物質は、ダイオキシン分解菌のスクリーニングに用いられており、この色素を含んだ寒天培地上で透明なゾーンを形成する微生物は、ダイオキシンを分解する能力を有する事が報告されている（鈴木源士、新嶋洋明、バイオテクノロジーを利用した低コストな環境負荷低減技術の開発−微生物を用いたダイオキシン汚染土壌修復システムの開発・実用化−、Ｈ１１年度提案公募ＮＥＤＯ事業成果報告会予稿集）。そういった意味では、本水溶液はダイオキシン汚染排水のモデルとして考える事もできるかもしれない。さて、本水溶液４０ｍｌを、５０ｍｌ容の三角フラスコ４０本にそれぞれ入れた。その上で（１）生石灰（和光一級、０３７−００７７５、和光純薬株式会社）５０ｍｇ、過酸化水素水（試薬特級、３０％、和光純薬株式会社）０．４ｍｌを添加し、７０℃で１２時間静置した区。（２）生石灰５０ｍｇ、過酸化水素水０．４ｍｌを添加し、２７℃で１２時間静置した区。（３）生石灰５０ｍｇを添加し、７０℃で１２時間静置した区。（４）生石灰５０ｍｇを添加し、２７℃で１２時間静置した区。（５）過酸化水素水０．４ｍｌを添加し、７０℃で１２時間静置した区。（６）過酸化水素水０．４ｍｌを添加し、２７℃で１２時間静置した区。（７）超純水０．４ｍｌを添加し、７０℃で１２時間静置した区。（８）超純水０．４ｍｌを添加し、２７℃で１２時間静置した区。の８通りの実験区を作り、それぞれ５連で１２時間後にＯＤ６００を測定し、分解効率を確認した。その結果、最もＯＤ６００が高かった区（８）の５連の平均値を１００と換算した場合の他の７区の％平均値は以下のようだった。（１）１５．９％（２）５１．８％（３）６９．１％（４）５４．８％（５）５１．６％（６）９３．６％（７）９９．１％（８）１００．０％。この結果から、生石灰と過酸化水素水の双方を添加し７０度で処理した区が、他の処理区と比べ格段に分解効率が高い事が確認できた。この結果は、難分解性のダイオキシンアナログを用いたモデル排水に、単に生石灰と過酸化水素水を添加し、７０℃で処理する操作を行うだけで簡単に難分解性有機物質が分解できる事実を示しており、石油やダイオキシン等の汚染浄化に広く使える事を示唆している。なお、出願日現在、実際の石油汚染土壌、ダイオキシン汚染土壌を用いた浄化実験を更に続行中で、そのうち石油汚染土壌の方は、わずか３日間の処理で石油臭及び石油色度が共に大きく低減できている事を既に確認できているが、公定法を含めた詳細な解析及び追試験は今後に待たれるので、その結果については、追試験結果が得られ次第、本基本特許を更に固める周辺特許として別に出願する予定である。しかし、論理さえとおっていれば実証データなしのアイデアだけでも成立すると言う日本特許の特質を考えれば、レマゾール・ブリリアント・ブルーＲというダイオキシンと構造がやや類似している難分解性有機物質を用いた今回の確認実験だけで、実際に本処理で難分解性有機物質が（従来法より）効率的に分解できている以上、本基本特許を出願するだけの必要かつ十分な根拠を提供しているものと考えられよう。
【００１９】
【発明の効果】
実施例で示したように、生石灰及び過酸化水素添加と熱処理を組み合わせるだけの単純な原理の本発明を用いれば、有害有機物質を含有する液体、排水、固体等を、安価かつ簡便に浄化する事が可能となり、単純であるだけに、その応用範囲は広い。従って、本発明は、生石灰及び過酸化水素と熱処理を伴うあらゆる環境浄化、食品の安全性向上等に幅広く有効であるものと考えられる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for removing various harmful organic substances in (1) liquids such as wastewater and food, and (2) solids such as soil and fly ash.
[0002]
[Prior art]
Conventionally, methods for removing harmful chemical substances include various methods such as (1) a method for restoring a biological environment using microorganisms and plants, (2) a combustion method, (3) an accelerated oxidation method, and (4) a solvent washing method. Among them, the bioenvironmental remediation method is not only difficult to use because oil growth is not only inhibited when the degree of oil pollution is large, but also because there is concern about ecosystem disruption for the introduction of foreign organisms. On the other hand, physicochemical methods such as the combustion method have drawbacks that they consume large amounts of energy and are costly. Therefore, there is a constant demand for the development of technologies that are cheaper, more efficient, and more environmentally friendly than conventional technologies. The present invention is a new technology based on the hydroxy radical generation method made under such a background, and is designed to improve decomposition efficiency, economic efficiency and reduce energy consumption compared to the conventional method. .
[0003]
In the present invention, although quicklime is mainly used as a decomposing agent, as a conventional technique using quicklime, first, a method and apparatus for reducing, solidifying, and stabilizing dioxin in molten fly ash by Kawasaki Heavy Industries, Ltd. 11-99371) ". This patent is characterized by adding any of quick lime, slaked lime, limestone, and clay to molten fly ash, slurried with water, and then heat-treated at 600 to 900 ° C. However, oxidizing agents such as hydrogen peroxide Since no treatment is added, degradation of the decomposition efficiency as compared with the present invention is not only predicted from the model experiments shown in the examples of the present invention, but also the heat treatment is in the range of room temperature to 100 ° C. in the present invention. On the other hand, in this patent, the temperature is as high as 600 to 900 ° C., and the energy efficiency is remarkably inferior, and the cost is correspondingly increased. In addition, the object to be decomposed is limited to only molten fly ash, and it can be determined that it does not compete with the present invention in such a meaning.
[0004]
EBARA CORPORATION also states in the "Method of Decomposing Aromatic Halogen Compounds (Japanese Patent Application Laid-Open No. Hei 7-265461)" that solid substances such as soil having a water content of 5% or more, alkaline substances such as quicklime and slaked lime and aluminum. Alternatively, a method is provided in which a metal is added, mixed, and heated to 300 ° C. to 450 ° C. However, since an oxidizing agent treatment such as hydrogen peroxide is not added, the model experiment shown in the example of the present invention is performed. In addition, it is predicted that the decomposition efficiency is lowered as compared with the present invention, and the heat treatment is also high at 300 ° C. to 450 ° C., resulting in poor energy efficiency. In addition, EBARA CORPORATION separates from the above-mentioned patent, "Solution method for dioxins in solids (Japanese Patent Laid-Open No. 2000-197867)", "Slurry under normal temperature to 100 ° C temperature conditions, ferrous sulfate and Dioxin decomposition method by adding hydrogen peroxide solution '', but without using ferrous sulfate which has the difficulty of remaining and causing heavy metal contamination, simply adding both quicklime and hydrogen peroxide No mention is made of the fact that the organic matter resolution can be remarkably promoted only by setting the temperature to a high temperature, and does not compete with the present invention.
[0005]
In addition, Yuka Sangyo Co., Ltd., in the "Hazardous Environmental Pollutant Detoxification Method (Japanese Patent Application Laid-Open No. 2000-343059)," Claim on the method of detoxifying harmful environmental pollutants (Claim 1), which is not only combined with the treatment with an oxidizing agent such as hydrogen peroxide, but also Since the heat treatment is not performed, not only that the decomposition efficiency is remarkably inferred from the model experiments shown in the examples of the present invention, but also the use of quick lime No claim can be made for ordinary quicklime (confirmed strong activity in the examples of the present invention).
[0006]
In addition, in "Method of detoxifying polychlorinated aromatic compounds (JP-A-2001-79109)", Masaru Yamauchi added water to oil containing polychlorinated aromatic compounds, emulsified the oil, added quicklime, and heated. However, since an oxidizing agent such as hydrogen peroxide is not added to this treatment, the resolution is significantly higher than that of the present invention based on the data of the model experiment shown in the embodiment of the present invention. Not only is it expected that the oil will fall, but the claims also limit the decomposition target to "oil containing a polychlorinated aromatic compound", so it is considered not to compete with the present invention.
[0007]
Regarding a related patent relating to an accelerated oxidation treatment using a hydroxy radical, a method and an apparatus for treating incinerated ash by Mitsubishi Heavy Industries, Ltd. (Japanese Patent Application Laid-Open No. 2001-137803) can be mentioned. A harmful organic substance group contained in the ash is mixed with water to form a slurry, and the slurry is oxidatively decomposed in the presence of hydroxy radicals. " However, (i) only incinerated ash (which is easier to decompose than soil and sediment) is claimed, and soil, sediment and liquid (which are harder to decompose than fly ash and have greatly different physical properties and biological properties) are claimed. And not. In addition, only (ii) the hydroxy radical production means is described as “by combining hydrogen peroxide, ultraviolet irradiation, catalyst, and ozone aeration in a neutral or weakly alkaline state (pH 7 to 9)”. In the process of generating radicals, the decomposition efficiency is dramatically increased by combining quick lime, hydrogen peroxide, and heat treatment under strong alkaline conditions, mainly at pH 9 or higher, rather than under weak alkaline conditions where the amount of generated hydroxyl radicals is small. We are unaware of what we can do, at which point we can assert the uniqueness, new regulations and effectiveness of our invention. In addition, the patent issued by Mitsubishi Heavy Industries, Ltd. has the idea of "using the wastewater from the incineration plant to make the burnt ash into a slurry," but there is no mention of using it under hot water (high temperature) conditions. Without that, it is difficult to efficiently produce hydroxyl radicals. In addition, it is mentioned that "sodium hydroxide and calcium hydroxide are used" in the case of alkaline conditions, but sodium hydroxide is a poisonous substance and has problems in both use risk and persistence. In addition, calcium oxide (quick lime) not only significantly enhances the resolution of harmful organic substances than calcium hydroxide (slaked lime), and even if quick lime is used under strong alkaline conditions, it naturally becomes neutral with carbon dioxide in the air. Mitsubishi Heavy Industries, Ltd. was unaware of the fact that it caused a union reaction and did not easily cause a problem in persistence (that is, it was environmentally friendly), and positioned the present invention as an improvement over a series of these problems. Can be
[0008]
[Problems to be solved by the invention]
The purpose is to provide a technology that can decompose various harmful organic substances in liquids such as wastewater and foods, solids such as soil and fly ash, in comparison with conventional methods, at low cost, efficiently and with low energy. And
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a liquid or a solid obtained by adding water to a slurry is combined with addition of both an alkali agent such as quicklime and hydrogen peroxide and heat treatment (room temperature to 98 ° C.). A method for removing organic substances in a liquid and a method for removing bacteria may be applied. In addition, if necessary, there are a total of four treatments (1) ozone, light irradiation, various oxidation treatments such as hypochlorous acid, (2) catalyst, (3) aeration or stirring, and (4) addition of a carbonized material such as activated carbon. If one or a plurality of them are combined, the resolution can be further promoted. Energy-saving purification plants and concrete mixer trucks designed to supply hot lime and hydrogen peroxide to hot water or hot spring water generated during the cooling process of refuse incineration plants, thermal power plants, etc. If a vehicle equipped with a tank capable of stirring slurry such as a heating device such as a boiler, a device for adding an alkali salt such as quick lime, a device for adding an oxidizing agent such as hydrogen peroxide, etc. It is possible to save energy and promote environmental purification. Further, it is also effective to combine the bioenvironmental remediation technology with the soil and the like partially purified using the present method as a hybrid purification method.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in more detail. The quicklime and hydrogen peroxide are mixed with the wastewater containing the organic substance, and the mixture is heat-treated at room temperature to 100 ° C (for example, about 70 ° C). At this time, it may be allowed to stand still, but it is better to perform stirring or aeration. By itself, the decomposition of organic substances and the elimination of bacteria can be remarkably promoted in comparison with the section where only quicklime treatment is performed, the section where only hydrogen peroxide treatment is performed, and the section where only quicklime and hydrogen peroxide are incubated at room temperature. At this time, the addition ratio of quicklime and hydrogen peroxide may be appropriately adjusted with reference to the specific examples shown in the embodiments of the present invention. The principle of this reaction is presumed to be that the generation efficiency of hydroxy radicals generated by the addition of hydrogen peroxide increases under strong alkaline conditions, and further heat treatment further increases the efficiency. Also, the use of quicklime as an alkali agent here, even in a strongly alkaline state, reacts with water and carbon dioxide in the air and is naturally neutralized into calcium carbonate via slaked lime, so that strong lime is used in the environment. This is because, at the same time, there is an advantage that the alkali state is hard to remain, and at the same time, it has an advantage of generating heat by reacting with water and increasing the efficiency of decomposing hydroxy radicals. Further, quick lime has an advantage that, similarly to hydrogen peroxide, it is inexpensive and the processing cost can be reduced compared to ozone treatment. When decomposing harmful substances (estrogens, dioxins, etc.) in liquid foods such as alcohol, it is not safe to use quicklime as an alkaline agent, and magnesium hydroxide which is also used as slaked lime or as a gastrointestinal drug It is necessary to use a highly safe alkaline agent, etc., and to minimize the addition of hydrogen peroxide so as not to harm health, or to irradiate ultraviolet rays to make sure that hydrogen peroxide is completely decomposed. Needless to say. In addition, if ultraviolet irradiation is utilized here, accelerated oxidation in foods is further promoted, and it is expected that the decomposition efficiency of not only hydrogen peroxide but also harmful organic substances is improved. In addition, the addition of these alkaline agents and hydrogen peroxide is not a large amount at a time, but is repeated at regular time intervals, thereby increasing the hydroxyl radical generation efficiency and heat generation efficiency throughout the operation time. It is desirable in increasing.
[0011]
Further, in order to further promote the decomposition reaction, means generally used in the accelerated oxidation reaction may be appropriately combined. Specifically, (1) ozone, light irradiation, various oxidation treatments such as hypochlorous acid, (2) catalyst, (3) aeration or stirring, (4) addition of carbonized material such as activated carbon, for a total of four treatments It is effective to combine one or more of them. However, care must be taken when treating soil or the like, since chlorine generated by hypochlorous acid treatment may be involved in the production of new harmful substances. In addition, if these processes are performed, the cost is increased accordingly. Therefore, it is better to purify with a system as simple as possible. In that sense, when purifying environmental contaminants, a method of adding quicklime and hydrogen peroxide and performing a heat treatment is considered to be the simplest and most effective method.
[0012]
Using these series of methods, not only can bacteria be removed, but also various harmful substances and odorous substances such as dioxins, PCBs, environmental hormones, residual pesticides, oils, and estrogens in various liquids such as wastewater and foods can be removed. It can be widely used for treating harmful organic substances in the environment and foods.
[0013]
In addition, this method can remove not only liquids but also harmful substances in solids such as soil, sediment, fly ash, and food materials. Add water to these soils, sediment, fly ash and food materials, add lime etc. mainly for soil, sediment and fly ash, and add slaked lime, magnesium hydroxide etc. Then, after the mixture is stirred, hydrogen peroxide is added, and heat treatment (normal temperature to 100 ° C.) may be performed. The processing time may be continued for several hours, and in some cases for several weeks, while monitoring the decomposition amount.
[0014]
In addition, in the heat treatment (normal temperature to 100 ° C.) in the series of reaction processes, factory wastewater for cooling plants (generating a large amount of heat) such as garbage incineration plants, thermal power plants, nuclear power plants, geothermal power plants, etc. Alternatively, a large energy saving effect can be expected if hot spring water is used as a heat source. More specifically, a new plant will be described. For example, (1) a device for adding hydrogen peroxide at regular intervals to a fixed section of a drainage channel through which factory wastewater of 70 ° C. or higher flows, and (2) quicklime at regular intervals. A total of five devices are installed: (3) a stirring device, (4) a device for adding contaminants (contaminated soil, ash, etc.), and (5) a device for discharging contaminated materials. What is necessary is just to separate the front and back of a division with a filter. If necessary, if this plant is further equipped with (1) an ozone generator, (2) an ultraviolet irradiation device, etc., which are related to the accelerated oxidation described in claim 3, the decomposition efficiency is expected to be further increased. Is done. In the case of using hot spring water, it is expected that decomposition can be promoted more efficiently and economically if alkaline hot spring water containing sodium bicarbonate or the like as the main component is used. Care must be taken to ensure that waste is not lost in waste disposal.
[0015]
Furthermore, as a new plant that we would like to provide, a vehicle equipped with a tank capable of stirring slurry, such as a concrete mixer truck, a heating device such as a boiler, a device for adding alkali salts such as quicklime, a device for adding an oxidizing agent such as hydrogen peroxide, etc. And a mobile vehicle plant designed to purify contaminated soil, ash, sediment, etc. at the site of contamination. If required for this vehicle, as described in claim 3, it is expected that the decomposition efficiency will be further enhanced by combining an ozone water generator, an ultraviolet irradiation device, and the like. If there is such a plant, for example, after sending several modified mixer trucks to soil contaminated with dioxin and let them decompose on the spot over several months, drive as it is, It is possible to take a purification method such as moving to a polluted place, and it is expected that purification with mobility can be performed.
[0016]
In addition, quicklime, slaked lime, etc. used in this series of purification treatments are generally used as fertilizers / soil improvers in agriculture. Therefore, soil and bottom mud partially purified using these series of methods, It is expected that planting in soil and the like to which wastewater purified by use is added is relatively easy. Therefore, this technology can be used as a contaminated land revegetation technology, and the plant microorganisms that naturally (slowly) coexist with the plant itself or the roots of the plant secrete laccase, etc., and decompose the remaining oily substances to recover the plant environment. It can also be expected to have an effect and a microbial environment restoration effect (hybrid purification). The plant species used here may be selected according to the pollutant to be purified. For example, in the case of dioxin, it has been reported by Idemitsu Kosan Co., Ltd. that lacquer having a high laccase activity is effectively decomposed (a method for purifying chlorinated dioxin-contaminated soil or water, JP-A-2001-232345). It is also possible that a certain percentage of oily contaminants may accumulate on plants grown in this contaminated soil area. Later, harvesting and disposal as industrial waste would also be effective. In addition, in planting, soil neutralized by quick lime treatment, etc., may be added acid soil improver such as peat moss or compost to accelerate the neutralization, or even plant an alkalophilic plant Good. Furthermore, since many of the indigenous bacteria have died in the soil and the like purified by the method of claims 1 to 7, the effect that exogenous microorganisms can easily colonize is also expected, and without planting. A hybrid purification method combining microbial environment remediation techniques, such as simply adding harmful substance decomposing microorganisms or adding various composts, is also effective.
[0017]
Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to only the following examples.
[0018]
【Example】
Remazol Brilliant Blue R (Sigma) was added to sterilized ultrapure water and dissolved to a concentration of 15 ppm to obtain model wastewater. This aqueous solution exhibits a light blue color. This substance has been used for screening dioxin-degrading bacteria, and it has been reported that microorganisms that form a transparent zone on agar medium containing this dye have the ability to degrade dioxin (Genji Suzuki) , Hiroaki Niijima, Development of Low-Cost Environmental Impact Reduction Technology Using Biotechnology-Development and Practical Use of a Dioxin-Contaminated Soil Remediation System Using Microorganisms-Proposal for NEDO Business Results Report Proposal for FY11 Proposal). In this sense, the aqueous solution could be considered as a model for dioxin-contaminated wastewater. Now, 40 ml of the present aqueous solution was placed in each of 40 50 ml Erlenmeyer flasks. Then, (1) 50 mg of quicklime (Wako first grade, 037-00775, Wako Pure Chemical Industries, Ltd.) and 0.4 ml of hydrogen peroxide solution (reagent special grade, 30%, Wako Pure Chemical Industries, Ltd.) were added, and the mixture was heated at 70 ° C. A ward that was left standing for 12 hours. (2) A section to which 50 mg of quicklime and 0.4 ml of hydrogen peroxide solution were added and left at 27 ° C. for 12 hours. (3) A section to which 50 mg of quicklime was added and left at 70 ° C. for 12 hours. (4) A section to which 50 mg of quicklime was added and allowed to stand at 27 ° C. for 12 hours. (5) A section to which 0.4 ml of aqueous hydrogen peroxide was added and allowed to stand at 70 ° C. for 12 hours. (6) A section to which 0.4 ml of a hydrogen peroxide solution was added and left at 27 ° C. for 12 hours. (7) A section to which 0.4 ml of ultrapure water was added and left at 70 ° C. for 12 hours. (8) A section to which 0.4 ml of ultrapure water was added and left at 27 ° C. for 12 hours. 8 experimental plots were prepared, and OD600 was measured after 12 hours in 5 replicates each to confirm the decomposition efficiency. As a result, when the average value of the five replicates in the section (8) having the highest OD600 was converted to 100, the% average values in the other seven sections were as follows. (1) 15.9% (2) 51.8% (3) 69.1% (4) 54.8% (5) 51.6% (6) 93.6% (7) 99.1% ( 8) 100.0%. From this result, it was confirmed that the section where both quicklime and hydrogen peroxide solution were added and treated at 70 ° C. had remarkably higher decomposition efficiency than the other sections. This result demonstrates that simply adding calcined lime and aqueous hydrogen peroxide to a model wastewater using a hardly decomposable dioxin analog and treating it at 70 ° C can easily decompose hardly decomposable organic substances. It suggests that it can be widely used for purification of pollution of petroleum and dioxin. As of the filing date, purification experiments using actual petroleum-contaminated soil and dioxin-contaminated soil are being continued, and of those petroleum-contaminated soils, both petroleum odor and petroleum chromaticity are greatly reduced by treatment for only three days. Although it has already been confirmed that this has been done, detailed analysis including the official method and follow-up tests are awaited in the future, and the results will be confirmed as soon as the follow-up test results are obtained. It will be filed separately as a patent. However, given the uniqueness of the Japanese patent, which states that even ideas without empirical data can be realized if the logic is taken into account, the use of a hardly decomposable organic substance called Remazol Brilliant Blue R whose structure is somewhat similar to dioxin is used. This confirmation experiment alone provides a necessary and sufficient basis for filing the basic patent, as the hard-to-decompose organic substance can be decomposed efficiently (compared to the conventional method) with this treatment. Would be considered.
[0019]
【The invention's effect】
As shown in the examples, if the present invention having a simple principle of simply combining the heat treatment with the addition of quick lime and hydrogen peroxide, the liquid containing harmful organic substances, waste water, solids, etc. can be purified inexpensively and easily. Things are possible, and their simplicity has a wide range of applications. Therefore, it is considered that the present invention is widely effective for purification of all kinds of environment involving heat treatment with quick lime and hydrogen peroxide, improvement of food safety, and the like.