JP3645613B2 - Air purification device for underground space - Google Patents

Description

【０００８】
また、上記公知資料には、一酸化窒素のオゾン酸化が以下のように行なわれると記載されている。
ＮＯ＋Ｏ₃ → ＮＯ₂＋Ｏ₂ ・・・・・（１）
２ＮＯ＋Ｏ₃ → Ｎ₂Ｏ₅＋Ｏ₂ ・・・・（２）
なお、上記（１）の反応は速やかに進むが、（２）の反応は遅い。
【０００９】
そして、本発明法は「表１」の酸化吸収法、すなわち、前項（２）の反応を使用し反応性の乏しい一酸化窒素を二酸化窒素となした後、水等の吸収液に効率的に吸収するものに最も類似するものであるが、この方法はオゾン発生機が高価で、吸収速度が遅い欠点を有するとされている。
【００１０】
【発明が解決しようとする課題】
しかし、地下空間内の空気を処理せずに特定の場所より排気する前記従来の換気法は、有害物質が処理されないこと自体、自然環境に悪影響を及ぼす課題を有し、さらには、この方式は有害物質を特定地域に集めて連続的に排気することになり、自然環境に及ぼす影響が特定地域において集中して特に大きな悪影響を与えるという課題を有している。
【００１１】
もっとも、従来の換気法で、換気口で排気を処理することも提案されているが、排気量が多くなるとその浄化に要する経費は累進的に高騰し、大規模トンネル等ではその排気を浄化することが経済的に不可能とされている課題を有するものである。
【００１２】
また、従来のバッグフィルター方式、湿式スクラバー方式、電気集塵機等は、技術が古くより確立されたものであるが、特に地下空間の空気を浄化するには、空気の湿潤、カビ等の微生物の殺菌、臭気の脱臭等の諸条件をいずれも満足できるものがなく、例えば、バッグフィルター方式は脱臭できず、微生物は濾過できないという課題を有し、電気集塵機は集塵効率が高いがバッグフィルター方式と共に保守点検が煩雑であり、湿式スクラバー方式は保守点検が容易であるが、脱臭や殺菌はできないという課題を有している。なお、これらのいずれの方式も脱硝効果はほとんど期待できない。
【００１３】
そこで、保守点検が容易な、湿式スクラバー方式の前段処理にオゾンガスと地下空間内の空気とを接触させ、オゾンで脱臭、殺菌、さらには一酸化窒素等を捕集し易い分子に酸化して、次いで湿式スクラバーでこれらを捕集する「オゾン処理空気浄化装置」（前記した、酸化吸収法の相当する。）が注目されるようになってきた。特に、この方式は自動車トンネルや地下駐車場の空気浄化装置に効果的であるとして最近注目されているが、従来の放電式のオゾナイザーをトンネル等の地下空間内において運転することは、前記したようにオゾン発生機が効果である課題、二酸化窒素の吸収液への吸収速度が遅いので大型な処理槽が必要となる課題以外に以下のごとき課題を有するものである。
１、 放電式オゾナイザーは大型で大きなスペースを占有する。
２、 トンネル等の地下空間内の湿潤した空気を原料気体に使用すると、オゾン発生効率が著しく低下し窒素酸化物の発生が増える。
３、 トンネル等の地下空間内の湿潤した空気でオゾナイザ−の高電圧部位での短絡事故が発生し易い。
４、 万が一高濃度の気相のオゾンが漏出すると、オゾンガスは人間にとって有害物質であり危険性を内包するものである。特に密閉率の高い地下空間に漏れた気相のオゾンが溜ると大きな事故が発生することが想定できる。
５、 放電式オゾナイザーは頻繁な保守・点検を行わないと、所定のオゾン発生効率を維持できない。
【００１４】
また、地下室等の比較的小容量の空気浄化装置には、前記したようなフィルターで外気等を濾過するのが適しているとされるが、フィルターは細菌等を捕集するのみであるので、保守・点検作業を順守しないと、一箇所に集めた細菌が不意にこぼれ落ちたり、フィルターの捕集面とは反対側面にまで細菌等が繁殖して高い信頼性を有するものでないという課題を有することが知られている。
【００１５】
そこで本発明は上記課題に鑑みなされたもので、水を電気分解して発生する酸素中にオゾンが混入することに着目し、このオゾンを電気分解中の水に溶解させたオゾン水を使用して、トンネル等の地下空間内での運転にも適すると共に小容量処理・大容量処理のいずれにもコンパクトな装置で対応でき、保守点検も簡易で、安全なトンネル等の地下空間の空気浄化装置を提供することを目的としたものである。
【００１６】
【課題を解決するための手段】
上記の目的に沿い、先述特許請求の範囲を要旨とする本発明の構成は前述課題を解決するために、固形電解質膜３１の一面に、オゾン発生触媒機能を有する金属を所定の開口率を有する多孔材となした陽極電極３２を重ね、他面に同じく所定の開口率を有する多孔材となした陰極電極３３を重ね、上記陽極電極３２と陰極電極３３とを覆う陽極側ジャケット３４と陰極側ジャケット３５とには夫々水流入口３６ａ，３６ｂと水流出口３７ａ，３７ｂとを設けてオゾン水生成セル３０を構成し、
上記陽極電極３２と陰極電極３３とを直流電圧電源３８に連結し、上記水流入口３６ａ，３６ｂには水供送管４０ａ，４０ｂを連結し、陽極側ジャケット３４の水流出口３７ａはトンネル等の地下空間内の空気が流過する処理槽１０に設けた第一噴射ノズル群１１ａに、陰極側ジャケット３５の水流出口３７ｂは上記処理槽１０に設けた第二噴射ノズル群１１ｂに夫々連結してなる技術的手段を講じたものである。
【００１７】
また、「請求項２」の発明は、「請求項１」記載の第二噴射ノズル群１１ｂが、処理槽１０内の第一噴射ノズル群１１より空気の流過下流側に位置させたことを特徴とする技術的手段を講じたものである。
【００１８】
また、「請求項３」の発明は、固形電解質膜３１の一面に、オゾン発生触媒機能を有する金属を所定の開口率を有する多孔材となした陽極電極３２を重ね、他面に同じく所定の開口率を有する多孔材となした陰極電極３３を重ね、上記陽極電極３２と陰極電極３３とを覆う陽極側ジャケット３４と陰極側ジャケット３５とには夫々水流入口３６ａ，３６ｂと水流出口３７ａ，３７ｂとを設けてオゾン水生成セル３０を構成し、
左右一端側に空気流入口１２を左右他端側に空気流出口１３を設けたトンネル等の地下空間内の空気が流過する処理槽１０内に、空気の流路を屈曲すると共に処理槽１０の底部においてドレーン水の通過を阻止しない邪魔板１７を設け、この邪魔板１７より空気流入口１２側に第一噴射ノズル群１１ａを、空気流出口１３側に第二噴射ノズル群１１ｂを収納し、さらに該処理槽１０の底部には排水口１８を設け、
上記オゾン水生成セル３０の陽極電極３２と陰極電極３３とを直流電圧電源３８に連結し、水流入口３６ａ，３６ｂには水供送管４０ａ，４０ｂを連結し、陽極側ジャケット３４の水流出口３７ａは前記第一噴射ノズル群１１ａに、陰極側ジャケット３５の水流出口３７ｂは前記第二噴射ノズル群１１ｂに夫々連結してなる技術的手段を講じたものである。
【００１９】
【作用】
それ故本発明地下空間の空気浄化装置は、オゾン水生成セル３０の陽極側ジャケット３４と陰極側ジャケット３５とに水を供送し、陽極電極３２と陰極電極３３との間に直流電圧を印加すると、陽極電極３２と陰極電極３３との間に固形電解質膜３１を介して電子の移動が生じ、その結果、水は電気分解され、陽極側ジャケット３４内に酸素が発生し、陰極側ジャケット３５内に水素が発生する。そして、陽極側ジャケット３４内では陽極電極３２が一種の触媒として作用し、発生する酸素の一部をオゾン化し、あるは直接オゾンを発生して、酸素と共にオゾンを発生させる。そして、この発生したオゾンは、酸素に比べ約１０倍程度水に溶解するので陽極側ジャケット３４内を流過する水に溶け込み、オゾン水（オゾンが溶け込んだ水をオゾン水と言う。）を生成するものである。
【００２０】
なお、陽極側ジャケット３４内の水には発生した水素が細かな気泡となって混入し水素気泡入り水を生成するものである。
【００２１】
そして本発明地下空間の空気浄化装置は、処理槽１０内で第一噴射ノズル群１１ａより噴射されるオゾン水とトンネル等の地下空間内の空気とが気液接触し、また、第二噴射ノズル群１１ｂより噴射される水素気泡入り水とトンネル等の地下空間内の空気とが気液接触し、トンネル等の地下空間内の空気に混入する粉塵はオゾン水と水素気泡入り水とによりに捕集される作用を呈する。
【００２２】
また、地下空間の空気に一酸化窒素が混入する場合、これらはオゾン水で酸化され二酸化窒素（ＮＯ₂）となり水に解け易くなり、水中に溶解して捕集される作用を呈する。なお、気相の一酸化窒素を気相のオゾンで酸化して二酸化窒素となし、次いで、この気相の二酸化窒素を水に吸収させると、吸収に時間を要するが、液相のオゾンと気相の一酸化窒素を接触させると、二酸化窒素への酸化と同時に水が存在するので直ちに水に溶け込み水への吸収時間は非常に効率的に行なえる作用を呈するものである。
【００２３】
また、トンネル等の地下空間内の空気に細菌・カビ等の微生物や臭気物質混入する場合、オゾン水は強力な酸化力でこれらを酸化して殺菌、分解して無毒化・無臭化する作用を呈する。
【００２４】
さらに、トンネル等の地下空間内の空気に、その他人間にとって有害な物質等、例えば種々の炭化水素等の疎水性物質が混入する場合、これらを酸化して親水性を向上させ、オゾン水及び水素気泡入り水に捕集し易くなす作用を呈するものである。
【００２５】
なお、電気分解に際して水中の塩素等のマイナスイオンの一部は固形電解質膜３１を通過して陽極側ジャケット３４側に移動するので、陽極側ジャケット３４側のオゾン水は酸性を呈し、陰極側ジャケット３５側の水素気泡入り水はアルカリ性を呈する。したがって、両者の水を噴霧することで排水は略中和される作用を呈するものである。
【００２６】
また、「請求項２」の発明は、先に第一噴射ノズル群１１ａよりオゾン水を噴霧して気流中に混入する物質の親水性を向上する酸化工程と、次いで第二噴射ノズル群１１ｂより噴霧される水素気泡入り水による還元捕集工程とが行われるので疎水性物質をも効率的に捕集できる作用を呈するものである。
【００２７】
さらに「請求項２」の発明は、オゾン水中のオゾンが消費されずに気相のオゾンとなったり、ミストの状態でこれが処理槽１０より流出する前に水素気泡入り水と接触して、水素とオゾンとを反応させオゾンの漏出を防ぐ作用を呈するものである。
【００２８】
また、「請求項３」の発明は、邪魔板１７より空気流入口１２側に第一噴射ノズル群１１ａを、空気流出口１３側に第二噴射ノズル群１１ｂを収納して、処理槽１０を横形となしたため、第二噴射ノズル群１１ｂより噴霧されたアルカリ性の水素気泡入り水が、第一噴射ノズル群１１ａのオゾン水噴射範囲に滴下することがなく、第一噴射ノズル群１１ａのオゾン水噴射による酸化を妨げないように作用するものである。
【００２９】
【実施例】
次に、本発明の実施例を添付図面にしたがって説明する。図中、３０がオゾン水生成セルで、このオゾン水生成セル３０は、固形電解質膜３１の一面にオゾン発生触媒機能を有する金属を所定の開口率を有する多孔材となした陽極電極３２を重ね、他面に同じく所定の開口率を有する多孔材となした陰極電極３３を重ねてある。
【００３０】
上記固形電解質膜３１は、耐オゾン性を有するフッ素系イオン交換膜が使用される。またオゾン発生触媒機能を有する金属としては、二酸化鉛（ＰｂＯ₂）がその代表例として知られているが、二酸化鉛を所定の開口率を有する多孔材に加工することは比較的困難で従来は焼成法等によって微小な通孔を有したポーラス材が提案されているが、このポーラスな二酸化鉛は脆弱で使用中に構成部材が崩れたりするので本実施例では、陽極電極３２に同じくオゾン発生触媒機能を有することが知られている白金（Ｐｔ）を使用した。なお、オゾン発生触媒機能を有する金属としてはその他に金（Ａｕ）等の貴金属が知られておりこれらを使用してもよいものである。
【００３１】
また、上記陽極電極３２を所定の開口率を有する多孔材となすには、本実施例では白金の線を編んで金網となし、その網目を開口部となしているが、その他金属板に多数の小通孔やスリットを設けたものを使用してもよい。
【００３２】
なお、陰極電極３３には、白金、金、銀（Ａｇ）、イリジュウム（Ｉｒ）等がオゾン生成に有利であることが実験の結果確認されており、本実施例では銀の金網を使用した。
【００３３】
そして、上記陽極電極３２と陰極電極３３とを覆う陽極側ジャケット３４と陰極側ジャケット３５とには、夫々水流入口３６ａ，３６ｂと水流出口３７ａ，３７ｂとを設けてある。
【００３４】
上記陽極側ジャケット３４と陰極側ジャケット３５は、両者で二つ割り容器状に構成され、両者の開口部を合わせる際に、固形電解質膜３１と陽極電極３２と陰極電極３３とを中央に挟持するようになしてある。なお、この陽極側ジャケット３４と陰極側ジャケット３５とは、耐オゾン水性の材質、例えばテフロンで構成し両者の開口部を合わせて図示しない締着螺子等で締結すると水流入口３６ａ，３６ｂと水流出口３７ａ，３７ｂとを除いて密閉できるようになし、中央部を固形電解質膜３１で仕切って、陽極側ジャケット３４の水流入口３６ａより流入した水は該陽極側ジャケット３４の水流出口３７ａより流出し、陰極側ジャケット３５の水流入口３６ｂより流入した水は該陰極側ジャケット３５の水流出口３７ｂより流出するようになしてある。
【００３５】
そして、上記陽極電極３２と陰極電極３３とを直流電圧電源３８に連結し、上記水流入口３６ａ，３６ｂには水供送管４０ａ，４０ｂを連結し、陽極側ジャケット３４の水流出口３７ａは、トンネル等の地下空間内の空気が流過する処理槽１０に設けた第一噴射ノズル群１１ａに、陰極側ジャケット３５の水流出口３７ｂは上記処理槽１０に設けた第二噴射ノズル群１１ｂに夫々連結してなる。
【００３６】
上記直流電圧電源３８は、商用交流電源を直流に整流する従来公知なもを使用すればよい。なお、本発明に使用される直流電源は陽極電極３２と陰極電極３３との間隙が狭い（この間隙は固形電解質膜３１の厚みであり、実施例では４００ミクロン）ため数十ボルト（実施例では２０〜４０ボルト）の比較的低い電圧でよいものである。
【００３７】
上記水供送管４０ａ，４０ｂは、その上流端を水道水供給源に連結し、水道水が供送されるようになしてもよいが、トンネル内では地下水が利用できる例が多く、地下水を利用する場合は、地下水をためる図示しない水槽より上記水供送管４０ａ，４０ｂを延設し、この水供送管４０ａ，４０ｂの途中にポンプ４１，４１（水道推理用の場合は、このポンプ４１，４１は不要にことが多い。）を介装するようになせばよい。なお、水供送管４０ａ，４０ｂの途中にはフィルター４２，４２を夫々介装しておくとよいのは無論である。
【００３８】
上記オゾン水生成セル３０の陽極側ジャケット３４と陰極側ジャケット３５とに水を供送し、陽極電極３２と陰極電極３３との間に直流電圧を印加すると、前記したように、陽極側ジャケット３４内を流過する水がオゾン水となり、陽極側ジャケット４内の水には発生した水素が細かな気泡となって混入し水素気泡入り水となるものである。
【００３９】
なお、電気分解に際して、水中に溶解している塩素（Ｃｌ）・カリュウム（Ｋ）等のマイナスイオンの一部は、電界によって吸引され固形電解質膜３１を通過して陽極側ジャケット３４側に移動するので、陽極側ジャケット３４側の水は酸性水となり、陰極側ジャケット３５側の水はアルカリ性水となるものである。
【００４０】
そして、上記第一噴射ノズル群１１ａは一端を陽極側ジャケット３４の水流出口３７ａに連結した下流側の水供送管４０ａより夫々分岐されて連結され、処理槽１０の一断面全面に渡って均一な分布で液滴（オゾン水）を噴霧するようになしてあり、二噴射ノズル群１１ｂは一端を陰極側ジャケット３５の水流出口３７ｂに連結した下流側の水供送管４０ｂより夫々分岐されて連結され、同じく処理槽１０の一断面全面に渡って均一な分布で液滴（水素気泡入り水）を噴霧するようになしてある。
【００４１】
なお、図示実施例ではこの陽極側ジャケット３４と陰極側ジャケット３５とには陽極電極３２または陰極電極３３と重ねてラス網体３９を夫々密入してある。このラス網体３９は耐食性金属板（実施例ではチタン板）に千鳥状に多数のスリットを入れ各スリット部が網目となるように引き伸ばして構成されたもので、「図３」に示すａが最高段部でその上部に低段部または上方に向かって低くなる傾斜面部ｂを有し、この傾斜面部ｂより斜め上方に延設される網線部ｃ，ｃが上段の最高段部ａに連結するようになっている。
【００４２】
上記ラス網体３９を陽極側ジャケット３４と陰極側ジャケット３５とに収納した理由は、発生したオゾンと水との接触頻度を向上するためと、電気分解で発生した酸素・オゾン・水素を直ちに水中に取り込み両電極間の導電性の低下を防止するためである。
【００４３】
上記のごとき陽極電極３２と陰極電極３３とを構成する金網及びラス網体３９はその面と直交方向には網目によって通水性を有すると共に、面方向にも通水性を有する。すなわち、ラス網体３９の両面を二枚の板で挟みその間に水を圧送すると、ラス網体３９の両面は凹凸となっているので両板と間隙を有する部分から水は次の網目に流入することになり、結果として面方向にも通水性が確保される。そして、この面方向の通水は網の交点部や網線部等に順次衝突しながら方向を転換し進行するので、非常に複雑な迷路状の流路を、衝突・方向転換・分流・合流を繰り返しながら流過することになる。したがって、水が複雑な迷路状の流路を通過することで、流過距離を長くすると共に攪拌作用を得て気液の接触頻度が向上するものである。
【００４４】
またラス網体３９を面方向に流過する水は、上記のように衝突・方向転換を行い小さな渦流を多数発生させることになる。すなわち、「図４」に矢印Ｙ１で示した網線部ｃを潜った流れは網目部内で渦流Ｙ２となる。そしてこの渦流Ｙ２は陽極電極３２と固形電解質膜３１との間に発生し気泡状となった酸素及びオゾンをその部位より掃引することになる。上記気泡は電気的には不良導体であるので、気泡が陽極電極３２と固形電解質膜３１との間に介在すると電流が流れづらくなり、結果として活発な電気分解が行われないことになるが、発生直後にこの気泡を渦流Ｙ２で掃引すると電流値の低下が無く効率的な電気分解が行えるものである。なお、陰極電極３３側も上記と同じである。
【００４５】
また、前記した処理槽１０は、一端に空気流入口１２を他端に空気流出口１３を設け、空気流入口１２と空気流出口１３とにはそれぞれ先端をトンネル等の地下空間内に開口する気流流路２０ａ，２０ｂを設け、この気流流路２０ａ，２０ｂの途中にはブロア２０ｃが介装され、トンネル内の空気は該ブロア２０ｃによって処理槽１０内を流過してトンネル等の地下空間内に戻るようになしてある。
【００４６】
そして、この処理槽１０内には前記第一噴射ノズル群１１ａと第二噴射ノズル群１１ｂとが設けられ、この第一噴射ノズル群１１ａ及び第二噴射ノズル群１１ｂより噴霧された水滴とトンネル等の地下空間内の空気とが接触して、地下空間内の空気中に混入する粉塵等が噴霧液滴に捕集されて浄化された空気が地下空間内に戻されるようになしてあるのは従来の湿式スクラバーと略同様である。なお、該処理槽１０は地下空間内に設置してもよく、地下空間と仕切られた場所（地上をも含む）に設置してもよい。
【００４７】
従来の湿式スクラバーは、大容量の空気浄化装置として汎用され、粉塵等は効率的に捕集されることが確認されているが、ＮＯ_Xや炭化水素等の疎水性物質はほとんど捕集できないとされている。しかし、本発明はオゾン水が噴霧されるため、オゾン水の液滴に接触したこれらの疎水性物質はオゾンの強力な酸化力で酸化され水に溶け易い、言い換えると液滴に捕集し易い性状に変化し効率的に捕集されることになる。また、臭気成分はオゾンで酸化され脱臭され、微生物はオゾンによって死滅するものである。
【００４８】
なお、図示例では上記処理槽１０内に充填接触層１４を設けてある。図示例ではこの充填接触層１４（コンタクトベッドとも称する。）は金網を複数枚重ねたものを使用しているが、この充填接触層１４は表面積を大きくして噴霧したオゾン水の液滴の一部がその表面に付着してより効率的な気液接触がなされるようになすものである。なお、この充填接触層１４は金網の他の小石等の小片を使用してもよいが、従来この種の充填物に汎用されている活性炭は、「図１」例ではオゾン水が気流と共に上昇して付着すると消耗するので本発明ではここでの使用には向いていない。なお、この充填接触層１４は上記以外の従来知られている他の方式のものを使用してもよいのは無論である。
【００４９】
上記充填接触層１４は、図示例では第一噴射ノズル群１１ａの上方に設けてあるが、上下いずれか一方または双方に配してもよく、第一噴射ノズル群１１ａの上方に設けたものは、噴霧されるオゾン水の液滴が細かく、気流に随伴して上昇したものがこの、表面積の大きな充填接触層１４に接触して捕集され、大きな液滴となって滴下するようになすもので噴霧液滴の細かい場合に使用するに適するとされている。また、第一噴射ノズル群１１ａの下方に設けた充填接触層１４は噴霧液滴が直接降りかかるようにして使用するもので、比較的噴霧液滴の粒径が大きく噴霧量を多くして使用する場合に適するとされている。そして、本発明ではオゾン水による酸化に多少の反応時間（数秒乃至十数秒）を要するのと、気流の流過速度は遅くして、気液接触頻度を増すため噴霧液滴の粒径は細かくするのが効率的であるので、前者の第一噴射ノズル群１１ａの上方に充填接触層１４を配する方式を採用するのが望ましい。
【００５０】
なお、上記充填接触層１４は図示例では第二噴射ノズル群１１ｂ側にも同様に設けてある。そして、この充填接触層１４は図示例では斜設してあるが、これは表面に付着した液滴が液層となって処理槽１０の内面側に移動し易くし、該処理槽１０の内面を液層となって伝わって流下するようになすためである。
【００５１】
また、「図１」図示例では、処理槽１０の空気流出口１３近くにミストエリミネータ１５を設けてある。このミストエリミネータ１５は図示例では衝突板方式が採用され、気流に随伴して上昇する細かなミストが衝突して捕集されるようになしてあるが、前記充填接触層１４と同じ構造のものを使用してもよく、この部位ではオゾンが流過する頻度は少ないので活性炭を充填物として使用してもよく、万が一オゾンが流過しようとした場合、活性炭との接触でオゾンを分解するようになしてもよいものである。
【００５２】
また、「請求項２」の発明では、上記第二噴射ノズル群１１ｂが、処理槽１０内の第一噴射ノズル群１１ａより空気の流過下流側に位置させたことを特徴としている。
【００５３】
すなわち、本発明では気流への噴霧液滴を複数段で行うようになしてる。このように複数段での気液接触を行なったのは、第一の目的はオゾン水のオゾン濃度を所定に保つためで、オゾン水はオゾン濃度が一定以上でないと窒素の酸化が円滑に行なえず実験の結果では７〜１０ｐｐｍ程度のオゾン濃度が必要であり、同じ場所でオゾン水とそうでない水とを噴霧すると両者が混ざってオゾン濃度が低下するためである。
【００５４】
また、気流への噴霧液滴を複数段で行う第二の目的は、オゾン水は所定以上の濃度でないと殺菌・脱臭に効果がなく、例えば２〜３ｐｐｍのオゾン水で大腸菌は死滅するが、抗生の大きい細菌は５ｐｐｍ以上のオゾン水でないと死滅しないし、脱臭にも３〜５ｐｐｍ以上の濃度が必要で、殺菌・脱臭を目的とする気液接触部では先にオゾン水を接触させることが有利なためである。
【００５５】
また、気流への噴霧液滴を複数段で行う第三の目的は、水を有効利用するため、水素気泡入り水をも利用することが望ましいが、この水素気泡入り水はオゾン水と接触するとオゾンと水素とが激しく反応して、結果としてオゾンを無駄に消費してしまう。そこで、この水素気泡入り水はオゾン水と接触しないようにして利用するためである。
【００５６】
さらに気流への噴霧液滴を複数段で行う第四の目的、特に水素気泡入り水の噴霧を後段となした目的は、気流中に疎水性物質がある場合これを従来の単なる湿式スクラバーでは捕集しずらいが、オゾン酸化して水に溶け易くして、さらに次段で気液接触を行なうのが捕集に効率的であるためであり、さらにはオゾン水ミストやオゾン水から気相のオゾンとなったものが万一漏れ出ようとする場合、オゾンを水素と反応させてそれを防ぐためである。
【００５７】
なお、「図１」図示例では、上記処理槽１０に縦形のものを使用したが、収納スペースに十分な高さが得られない場合等は横形のものを使用してもよいのは無論で、「請求項３」の発明では、左右一端側に空気流入口１２を左右他端側に空気流出口１３を設けたトンネル等の地下空間内の空気が流過する処理槽１０内に、空気の流路を屈曲すると共に処理槽１０の底部においてドレーン水の通過を阻止しない邪魔板１７を設け、この邪魔板１７より空気流入口１２側に第一噴射ノズル群１１ａを、空気流出口１３側に第二噴射ノズル群１１ｂを収納し、さらに該処理槽１０の底部には排水口１８を設けたものを使用した。
【００５８】
上記のように横形の処理槽１０の採用は、高さスペースには充分な余裕がなく長さ方向にスペースの余裕があるトンネル内への設置に特に適しているが、そればかりか、第一噴射ノズル群１１ａの処理空間と第二噴射ノズル群１１ｂの処理空間とをより確実に画定できるという利点を有するものである。
【００５９】
すなわち、「図１」実施例のように第一噴射ノズル群１１ａと第二噴射ノズル群１１ｂとを上下に設けた場合、前記した充填接触層１４，１４によって第二噴射ノズル群１１ｂより噴霧した液滴が下降して第一噴射ノズル群１１ａの液滴噴霧領域までは侵入しないようになすことは可能（たとえば、前記したように、第二噴射ノズル群１１ｂより噴霧した液滴は処理槽１０の内面側を伝わって流下するようになす。）であるが、液滴の噴霧量が多かったり、噴霧液滴の粒径が大きいと第一噴射ノズル群１１ａと第二噴射ノズル群１１ｂとの両液滴噴霧領域が重なってしまうことがあるが、本項発明のように邪魔板１７で両液滴噴霧領域を仕切るとより確実に液滴噴霧領域を区分できるものである。
【００６０】
なお、上記邪魔板１７は従来公知なものを使用すればよく、図示例では、処理槽１０の底面より立設しその上辺を該処理槽１０の上面との間に所定の間隔を設けた下方仕切１７ａと、処理槽１０の上面より吊り下げその下辺を該処理槽１０の底面との間に所定の間隔を設けた上方仕切１７ｂとで構成し、この下方仕切１７ａと上方仕切１７ｂとは一定の間隔を有して平行状態となしてある。なお、この下方仕切１７ａと上方仕切１７ｂとは一方を省略したり３枚以上を使用してもよい。
【００６１】
したがって、上記邪魔板１７は気流の流路を屈曲ないし蛇行させることになるが、同時に処理槽１０の底部を仕切る場合がある。処理槽１０の底部を仕切ると、第一噴射ノズル群１１ａより噴霧された酸性水のドレーンと第二噴射ノズル群１１ｂより噴霧されたアルカリ性のドレーンとが別個に溜ることになり、これらを自然界に排出すると自然環境を損なうし、処理して排水するにも処理工程が複雑化するので、本発明では両ドレーンが混ざるように、邪魔板１７はドレーン水の通過を阻止しないものを使用している。なお、ドレーン水の通過を阻止しないようになすには、邪魔板１７底部に通孔を設けたり、邪魔板１７の下辺と処理槽１０の底面との間に多少の間隙を設ければよいのは無論である。
【００６２】
なお、「図５」実施例では下方仕切１７ａと上方仕切１７ｂとの間に充填接触層１４を設けてある。
【００６３】
【発明の効果】
本発明は上記のごときで、オゾン発生源に電気分解を応用しているので、トンネル等の地下空間内でも容易に入手できる水よりオゾンを得られ、その装置も極めて簡易、小型、安価な地下空間の空気浄化装置を提供できるものである。
【００６４】
また、固形電解質膜３１を挟んでの電気分解は１０〜３０Ｖ程度の低電圧で良く、直流電圧電源２０も小型でよく、湿潤したトンネル内等の地下空間で使用しても電気的短絡事故が発生しずらいトンネル空気浄化装置を提供できるものである。
【００６５】
さらに本発明は得られるオゾンはただちに水に溶解され液相となっているので取扱が容易で、オゾンガスの漏出は全くなく、万が一漏出ても安全性が非常に高いオゾン水であるから、トンネル内等の地下空間の人に悪影響を及ぼすことは、気相のオゾンを取り扱う場合に比べて極端に少ない地下空間の空気浄化装置を提供できるものである。
【００６６】
さらに、本発明は処理槽１０は従来公知な湿式スクラバーが使用でき、噴霧水にオゾン水を使用するので、コンパクトな装置で脱硝・脱臭・殺菌が可能で、さらに疎水性物質をも効率的に捕集できる地下空間の空気浄化装置を提供できるものである。
【００６７】
また、「請求項２」の発明は、第二噴射ノズル群１１ｂを第一噴射ノズル群１１ａの下流側に別途設けたので、前記「００５３」乃至「００５６」の項で説明した目的を達成でき、オゾン酸化がより効率的に行なえ、結果として効果的な空気浄化が行なえる地下空間の空気浄化装置を提供できるものである。
【００６８】
また、「請求項３」の発明は、処理槽１０を横形となしたのでトンネル内への設置に特に適し、さらには、第一噴射ノズル群１１ａの処理空間と第二噴射ノズル群１１ｂの処理空間とをより確実に画定し、より効率的なオゾン酸化（脱硝）・粉塵除去・殺菌・脱臭のできる地下空間の空気浄化装置を提供できるものである。
【図面の簡単な説明】
【図１】本発明トンネル空気浄化装置の一実施例を示す縦断面図である。
【図２】本発明に使用されるオゾン水製造部の縦断面図である。
【図３】本発明に使用されるラス網の平面図である。
【図４】本発明に使用されるオゾン水製造部の部分拡大断面図である。
【図５】別の実施例要部縦断面図である。
【符号の説明】
１０ 処理槽
１１ａ 第一噴射ノズル群
１１ｂ 第一噴射ノズル群
１２ 空気流入口
１３ 空気流出口
１７ 邪魔板
１８ 排水口
３０ オゾン水生成セル
３１ 固形電解質膜
３２ 陽極電極
３３ 陰極電極
３４ 陽極側ジャケット
３５ 陰極側ジャケット
３６ａ 水流入口
３６ｂ 水流入口
３７ａ 水流出口
３７ｂ 水流出口
３８ 直流電圧電
４０ａ 水供送管
４０ｂ 水供送管[0001]
[Industrial application fields]
The present invention relates to an air purification device for underground spaces suitable for purifying air in underground spaces such as tunnels, underground malls, underground parking lots and basements, and in particular, nitrogen monoxide in exhaust gas from automobile tunnels and underground parking lots. The present invention relates to an air purification device for underground space suitable for denitration. However, the present invention is not limited only to the purification of air in the underground space, and does not preclude application to an aseptic room or clean room on the ground.
[0002]
[Prior art]
Conventionally, various air purification devices for underground spaces such as tunnels have been proposed. However, while air purification in these underground spaces usually has a large processing capacity, large devices cannot be installed in a limited space. In large underground spaces, pilot tunnels and vertical shafts excavated during underground excavation are generally used for ventilation, and the “ventilation method” is generally used to simply ventilate the air in the underground space.
[0003]
In addition, as for the air purification device for underground spaces such as concrete tunnels that have been proposed in the past, the bag filter method, wet scrubber method, electrostatic precipitator, etc. have been proposed as being suitable for relatively large-capacity treatment. It has also been put to practical use.
[0004]
Conventionally, various air purification devices as described above are effective for dust collection, but nitrogen oxides (NO _x ) ・ Since substances such as odorous substances cannot be collected effectively, ozone and air generated by a discharge-type ozonizer are brought into air contact, and nitrogen monoxide (NO) that fills in automobile tunnels, underground parking lots, etc. is water. Nitrogen dioxide (NO ₂ ), And "Ozone treatment air purification device" that collects and removes nitrogen monoxide and dust with a gas-liquid contact device such as a wet scrubber (showering tower), and deodorizes and sterilizes with the strong oxidizing power of ozone. Proposed.
[0005]
In addition, since the basement is humid and there is little temperature change, microorganisms such as bacteria are easy to propagate, but there are few suitable devices to sterilize the air in a relatively small volume of the underground space, and there is no particular concern about hygiene. It is said that it is desirable to avoid the use of underground facilities. In addition, when installing an operating room or the like underground, a method is also adopted in which outside air is continuously filtered with a filter that cannot pass bacteria, etc., and the outside air continues to be delivered to the extent that the entire basement is somewhat pressurized. .
[0006]
The following “Table 1” is known as a conventionally known denitration method. (October 25, 1992, issued by the Association of Industrial Environment Management, 3 revisions / Pollution Prevention Measures [Atmosphere]) (hereinafter referred to as publicly known materials)
[0007]
[Table 1]

[0008]
In addition, the above-mentioned publicly known document describes that ozone oxidation of nitric oxide is performed as follows.
NO + O _Three → NO ₂ + O ₂ (1)
2NO + O _Three → N ₂ O _Five + O ₂ (2)
The reaction (1) proceeds rapidly, but the reaction (2) is slow.
[0009]
The method of the present invention uses the oxidation absorption method of “Table 1”, that is, the reaction of the above item (2) is used to efficiently convert nitrogen monoxide having poor reactivity into nitrogen dioxide, and then efficiently into an absorbing solution such as water. Although most similar to what it absorbs, this method has the disadvantages that the ozone generator is expensive and the absorption rate is slow.
[0010]
[Problems to be solved by the invention]
However, the conventional ventilation method for exhausting air from a specific place without treating the air in the underground space has a problem that harmful substances are not treated, and has a problem that adversely affects the natural environment. Hazardous substances are collected in a specific area and exhausted continuously, and the influence on the natural environment is concentrated in the specific area and has a particularly serious problem.
[0011]
Of course, it is also proposed to treat the exhaust at the ventilation port by the conventional ventilation method, but as the amount of exhaust increases, the cost required for purification increases progressively, and the exhaust is purified in large-scale tunnels, etc. This has a problem that is considered economically impossible.
[0012]
In addition, the conventional bag filter system, wet scrubber system, and electrostatic precipitator are technologies that have been established for a long time. In particular, in order to purify the air in the underground space, air is moistened, and microorganisms such as mold are sterilized. There is nothing that can satisfy all conditions such as deodorization of odor, for example, bag filter system has a problem that it cannot deodorize and microorganisms cannot be filtered, and electrostatic precipitator has high dust collection efficiency, but with bag filter system Maintenance inspection is complicated, and the wet scrubber system is easy to perform maintenance inspection, but has a problem that it cannot be deodorized or sterilized. In addition, almost none of these methods can be expected to have a denitration effect.
[0013]
Therefore, the ozone gas and the air in the underground space are brought into contact with the pretreatment of the wet scrubber system, which is easy to maintain and inspect, and the ozone is deodorized, sterilized, and further oxidized to molecules that easily collect nitrogen monoxide, Subsequently, an “ozone treatment air purifier” (corresponding to the above-described oxidation absorption method) that collects these with a wet scrubber has been attracting attention. In particular, this method has recently attracted attention as being effective for air purification devices in automobile tunnels and underground parking lots. However, as described above, the conventional discharge type ozonizer is operated in underground spaces such as tunnels. In addition to the problem that the ozone generator is effective and the problem that the absorption rate of nitrogen dioxide into the absorption liquid is slow, there are problems as follows.
1. Discharge type ozonizer is large and occupies a large space.
2. When moist air in the underground space such as a tunnel is used as a raw material gas, the ozone generation efficiency is remarkably lowered and the generation of nitrogen oxides is increased.
3. Short circuit accidents at high voltage parts of the ozonizer are likely to occur due to moist air in underground spaces such as tunnels.
If ozone in the gas phase with a high concentration leaks out, ozone gas is harmful to humans and contains danger. In particular, it can be assumed that a large accident will occur if gas-phase ozone leaks into an underground space with a high sealing rate.
5. The discharge-type ozonizer cannot maintain the specified ozone generation efficiency without frequent maintenance and inspection.
[0014]
In addition, it is said that it is suitable to filter outside air with a filter as described above for a relatively small capacity air purification device such as a basement, but the filter only collects bacteria, etc. If the maintenance and inspection work is not observed, the bacteria collected in one place will spill out unexpectedly, or the bacteria will propagate up to the opposite side of the filter's collection surface and not have high reliability. It has been known.
[0015]
Therefore, the present invention has been made in view of the above-mentioned problems, paying attention to the fact that ozone is mixed in oxygen generated by electrolyzing water, and using ozone water in which this ozone is dissolved in water being electrolyzed. In addition, it is suitable for operation in underground spaces such as tunnels, and is compatible with both small-capacity processing and large-capacity processing with a compact device, and is easy to maintain and inspect. Is intended to provide.
[0016]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the structure of the present invention, which is summarized in the above-mentioned claims along with the above object, has a predetermined opening ratio of a metal having an ozone generation catalyst function on one surface of the solid electrolyte membrane 31. The anode electrode 32 made of a porous material is overlapped, the cathode electrode 33 made of a porous material having the same predetermined aperture ratio is overlapped on the other surface, and the anode side jacket 34 and the cathode side covering the anode electrode 32 and the cathode electrode 33 are stacked. The jacket 35 is provided with water inlets 36a and 36b and water outlets 37a and 37b, respectively, to constitute the ozone water generating cell 30,
The anode electrode 32 and the cathode electrode 33 are connected to a DC voltage power supply 38, the water inlets 36a and 36b are connected to water supply pipes 40a and 40b, and the water outlet 37a of the anode side jacket 34 is connected to an underground such as a tunnel. The water outlet 37b of the cathode side jacket 35 is connected to the second injection nozzle group 11b provided in the processing tank 10 to the first injection nozzle group 11a provided in the processing tank 10 through which the air in the space flows. It takes technical measures.
[0017]
Further, in the invention of "Claim 2", the second injection nozzle group 11b described in "Claim 1" is positioned on the downstream side of the air flow from the first injection nozzle group 11 in the treatment tank 10. It takes technical measures that are characteristic.
[0018]
Further, in the invention of "Claim 3", an anode electrode 32 made of a porous material having a predetermined opening ratio made of a metal having an ozone generation catalyst function is superposed on one surface of the solid electrolyte membrane 31, and the predetermined surface is also formed on the other surface. The cathode electrode 33 made of a porous material having an aperture ratio is stacked, and the anode side jacket 34 and the cathode side jacket 35 covering the anode electrode 32 and the cathode electrode 33 are respectively provided with water inlets 36a and 36b and water outlets 37a and 37b. To constitute the ozone water generation cell 30,
An air flow path is bent in the processing tank 10 in which air in an underground space such as a tunnel, in which an air inlet 12 is provided on the left and right ends and an air outlet 13 is provided on the left and right ends, and the processing tank 10 is bent. A baffle plate 17 that does not block the passage of drain water is provided at the bottom of the first jet nozzle group 11a on the air inlet 12 side and the second jet nozzle group 11b on the air outlet 13 side. Furthermore, a drain port 18 is provided at the bottom of the treatment tank 10,
The anode electrode 32 and the cathode electrode 33 of the ozone water generation cell 30 are connected to a DC voltage power supply 38, water supply pipes 40a and 40b are connected to the water inlets 36a and 36b, and the water outlet 37a of the anode side jacket 34 is connected. Is provided with technical means in which the first injection nozzle group 11a and the water outlet 37b of the cathode side jacket 35 are connected to the second injection nozzle group 11b, respectively.
[0019]
[Action]
Therefore, the air purification apparatus for underground space of the present invention supplies water to the anode side jacket 34 and the cathode side jacket 35 of the ozone water generation cell 30 and applies a DC voltage between the anode electrode 32 and the cathode electrode 33. Then, movement of electrons occurs between the anode electrode 32 and the cathode electrode 33 through the solid electrolyte membrane 31. As a result, water is electrolyzed, oxygen is generated in the anode side jacket 34, and the cathode side jacket 35 is generated. Hydrogen is generated inside. In the anode side jacket 34, the anode electrode 32 acts as a kind of catalyst, and a part of the generated oxygen is ozonized, or ozone is directly generated to generate ozone together with oxygen. Since the generated ozone is dissolved in water about 10 times as much as oxygen, it is dissolved in water flowing through the anode side jacket 34 to generate ozone water (water in which ozone is dissolved is referred to as ozone water). To do.
[0020]
The water in the anode side jacket 34 is mixed with the generated hydrogen as fine bubbles to generate water containing hydrogen bubbles.
[0021]
In the underground air purification apparatus of the present invention, the ozone water injected from the first injection nozzle group 11a in the treatment tank 10 and the air in the underground space such as a tunnel are in gas-liquid contact, and the second injection nozzle The hydrogen bubbled water jetted from the group 11b is in gas-liquid contact with the air in the underground space such as the tunnel, and the dust mixed in the air in the underground space such as the tunnel is captured by the ozone water and the hydrogen bubbled water. It exhibits the action that is collected.
[0022]
In addition, when nitrogen monoxide is mixed in the air in the underground space, these are oxidized with ozone water and nitrogen dioxide (NO ₂ ) And easily dissolved in water, and exhibits the action of being dissolved and collected in water. It should be noted that if gas phase nitrogen monoxide is oxidized with gas phase ozone to form nitrogen dioxide, and then this gas phase nitrogen dioxide is absorbed by water, it takes time to absorb, but liquid phase ozone and gas are absorbed. When the phase is in contact with nitric oxide, water is present at the same time as oxidation to nitrogen dioxide, so that it immediately dissolves in water and the absorption time into water exhibits an effect that can be performed very efficiently.
[0023]
In addition, when microbes such as bacteria and mold and odorous substances are mixed in the air in underground spaces such as tunnels, ozone water has the ability to oxidize and sterilize and decompose, detoxify and debromide with strong oxidizing power. Present.
[0024]
In addition, when other substances harmful to humans, such as various hydrophobic substances such as hydrocarbons, are mixed in the air in underground spaces such as tunnels, these are oxidized to improve hydrophilicity, and ozone water and hydrogen It has an effect of being easily collected in the water containing bubbles.
[0025]
During electrolysis, some of the negative ions such as chlorine in the water pass through the solid electrolyte membrane 31 and move to the anode side jacket 34 side. Therefore, the ozone water on the anode side jacket 34 side exhibits acidity, and the cathode side jacket 34 The water containing hydrogen bubbles on the 35 side exhibits alkalinity. Therefore, the waste water is substantially neutralized by spraying both waters.
[0026]
Further, the invention of "Claim 2" is based on an oxidation process in which ozone water is first sprayed from the first injection nozzle group 11a to improve the hydrophilicity of a substance mixed in the airflow, and then from the second injection nozzle group 11b. Since the reducing and collecting step is performed using the water containing hydrogen bubbles to be sprayed, the hydrophobic substance can be efficiently collected.
[0027]
Furthermore, the invention of "Claim 2" is that the ozone in the ozone water is not consumed and becomes ozone in the gas phase, or comes into contact with the water containing hydrogen bubbles before it flows out of the treatment tank 10 in the mist state. And ozone are reacted to prevent leakage of ozone.
[0028]
Further, the invention of "Claim 3" includes the first injection nozzle group 11a on the air inlet 12 side from the baffle plate 17 and the second injection nozzle group 11b on the air outlet 13 side, so that the treatment tank 10 is disposed. Since it became horizontal, the water containing alkaline hydrogen bubbles sprayed from the second injection nozzle group 11b does not drip into the ozone water injection range of the first injection nozzle group 11a, and the ozone water of the first injection nozzle group 11a. It acts so as not to prevent oxidation by injection.
[0029]
【Example】
Next, embodiments of the present invention will be described with reference to the accompanying drawings. In the figure, reference numeral 30 denotes an ozone water generating cell, and this ozone water generating cell 30 has an anode electrode 32 made of a porous material having a predetermined opening ratio made of a metal having an ozone generating catalyst function on one surface of a solid electrolyte membrane 31. A cathode electrode 33 made of a porous material having a predetermined aperture ratio is also stacked on the other surface.
[0030]
The solid electrolyte membrane 31 is a fluorine ion exchange membrane having ozone resistance. As a metal having an ozone generation catalyst function, lead dioxide (PbO) is used. ₂ ) Is known as a representative example, but it is relatively difficult to process lead dioxide into a porous material having a predetermined opening ratio. Conventionally, a porous material having minute through holes by a firing method or the like has been proposed. However, since this porous lead dioxide is fragile and its constituent members collapse during use, in this embodiment, platinum (Pt), which is also known to have an ozone generation catalytic function, is used for the anode electrode 32. did. In addition, noble metals such as gold (Au) are known as the metal having an ozone generation catalytic function, and these may be used.
[0031]
Further, in order to make the anode electrode 32 a porous material having a predetermined opening ratio, in this embodiment, a platinum wire is knitted to form a wire mesh, and the mesh is made an opening, but there are many other metal plates. Those provided with small through holes or slits may be used.
[0032]
The cathode electrode 33 has been confirmed by experiments that platinum, gold, silver (Ag), iridium (Ir), etc. are advantageous for ozone generation. In this embodiment, a silver wire mesh was used.
[0033]
The anode side jacket 34 and the cathode side jacket 35 that cover the anode electrode 32 and the cathode electrode 33 are provided with water inlets 36a and 36b and water outlets 37a and 37b, respectively.
[0034]
The anode-side jacket 34 and the cathode-side jacket 35 are both formed in a split container shape, and the solid electrolyte membrane 31, the anode electrode 32, and the cathode electrode 33 are sandwiched in the center when the openings of the two are combined. There is. The anode side jacket 34 and the cathode side jacket 35 are made of an ozone water-resistant material, for example, Teflon, and when both openings are combined and fastened with fastening screws (not shown), the water inlets 36a, 36b and the water outlet 37a and 37b can be hermetically sealed, the central part is partitioned by the solid electrolyte membrane 31, and the water flowing in from the water inlet 36a of the anode side jacket 34 flows out from the water outlet 37a of the anode side jacket 34, The water flowing in from the water inlet 36b of the cathode side jacket 35 flows out from the water outlet 37b of the cathode side jacket 35.
[0035]
The anode electrode 32 and the cathode electrode 33 are connected to a DC voltage power source 38, the water supply pipes 40a and 40b are connected to the water inlets 36a and 36b, and the water outlet 37a of the anode side jacket 34 is connected to the tunnel. The water outlet 37b of the cathode side jacket 35 is connected to the second injection nozzle group 11b provided in the processing tank 10, respectively, to the first injection nozzle group 11a provided in the processing tank 10 through which the air in the underground space flows. Do it.
[0036]
The DC voltage power supply 38 may be a conventionally known one that rectifies a commercial AC power supply to DC. Note that the DC power source used in the present invention has a narrow gap between the anode electrode 32 and the cathode electrode 33 (this gap is the thickness of the solid electrolyte membrane 31 and is 400 microns in the embodiment), so it is several tens of volts (in the embodiment, A relatively low voltage of 20 to 40 volts is sufficient.
[0037]
The water supply pipes 40a and 40b may be connected to a tap water supply source at the upstream end thereof so that tap water is supplied. However, there are many examples in which groundwater can be used in the tunnel, When using, the water supply pipes 40a and 40b are extended from a water tank (not shown) that stores groundwater, and pumps 41 and 41 (in the case of water supply reasoning, this pump is provided in the middle of the water supply pipes 40a and 40b). 41, 41 are often unnecessary). Needless to say, filters 42 and 42 may be provided in the middle of the water supply pipes 40a and 40b, respectively.
[0038]
When water is supplied to the anode side jacket 34 and the cathode side jacket 35 of the ozone water generation cell 30 and a DC voltage is applied between the anode electrode 32 and the cathode electrode 33, as described above, the anode side jacket 34 is provided. Water flowing through the inside becomes ozone water, and hydrogen generated in the water in the anode side jacket 4 is mixed into fine bubbles to become water containing hydrogen bubbles.
[0039]
During electrolysis, some of the negative ions dissolved in water, such as chlorine (Cl) and potassium (K), are attracted by an electric field and pass through the solid electrolyte membrane 31 and move to the anode side jacket 34 side. Therefore, the water on the anode side jacket 34 side becomes acidic water, and the water on the cathode side jacket 35 side becomes alkaline water.
[0040]
The first injection nozzle group 11 a is branched and connected from a downstream water supply pipe 40 a having one end connected to the water outlet 37 a of the anode side jacket 34, and uniform across the entire cross section of the treatment tank 10. The two-injection nozzle group 11b is branched from a downstream water supply pipe 40b having one end connected to the water outlet 37b of the cathode-side jacket 35. Similarly, droplets (water containing hydrogen bubbles) are sprayed in a uniform distribution over the entire cross section of the treatment tank 10.
[0041]
In the illustrated embodiment, a lath net 39 is closely inserted into the anode side jacket 34 and the cathode side jacket 35 so as to overlap the anode electrode 32 or the cathode electrode 33. The lath net 39 is formed by corrugating a metal plate (titanium plate in the embodiment) with a large number of slits in a zigzag pattern and extending each slit to form a mesh. The highest step portion has a lower step portion or an inclined surface portion b that is lowered upward at the upper portion thereof, and the mesh portions c and c extending obliquely upward from the inclined surface portion b are the upper highest step portion a. It comes to be connected.
[0042]
The lath net 39 is housed in the anode-side jacket 34 and the cathode-side jacket 35 in order to improve the contact frequency between the generated ozone and water, and the oxygen, ozone, and hydrogen generated by electrolysis are immediately removed from the water. This is to prevent a decrease in conductivity between the two electrodes.
[0043]
The wire mesh and lath mesh body 39 constituting the anode electrode 32 and the cathode electrode 33 as described above have water permeability through the mesh in the direction orthogonal to the surface and also water permeability in the surface direction. That is, when both sides of the lath net 39 are sandwiched between two plates and water is pumped between them, the both sides of the lath net 39 are uneven, so that water flows into the next mesh from the part having a gap with both plates. As a result, water permeability is ensured also in the surface direction. And this direction of water flow changes direction while sequentially colliding with the intersections and nets of the mesh, etc., so the very complicated labyrinth flow path is collided, redirected, diverted and merged. It will flow through while repeating. Therefore, when water passes through a complicated labyrinth-shaped flow path, the flow distance is increased and the stirring action is obtained to improve the gas-liquid contact frequency.
[0044]
Further, the water flowing through the lath net 39 in the plane direction collides and changes direction as described above to generate a large number of small vortex flows. That is, the flow that has gone through the mesh portion c indicated by the arrow Y1 in FIG. 4 becomes a vortex Y2 in the mesh portion. The vortex Y2 is generated between the anode electrode 32 and the solid electrolyte membrane 31, and oxygen and ozone in the form of bubbles are swept from the site. Since the bubbles are electrically defective conductors, if the bubbles are interposed between the anode electrode 32 and the solid electrolyte membrane 31, it becomes difficult for current to flow, and as a result, active electrolysis is not performed. If the bubbles are swept by the vortex Y2 immediately after the generation, the current value does not decrease and efficient electrolysis can be performed. The cathode electrode 33 side is the same as above.
[0045]
Further, the treatment tank 10 is provided with an air inlet 12 at one end and an air outlet 13 at the other end, and the air inlet 12 and the air outlet 13 are respectively opened at the tips into an underground space such as a tunnel. Air flow passages 20a and 20b are provided, and a blower 20c is interposed in the middle of the air flow passages 20a and 20b. The air in the tunnel flows through the processing tank 10 by the blower 20c and is underground space such as a tunnel. It is supposed to return inside.
[0046]
And in this processing tank 10, the said 1st injection nozzle group 11a and the 2nd injection nozzle group 11b are provided, the water droplet sprayed from this 1st injection nozzle group 11a and the 2nd injection nozzle group 11b, a tunnel, etc. The air in the underground space comes into contact with the dust in the underground space and the purified air is collected in the spray droplets and returned to the underground space. It is substantially the same as a conventional wet scrubber. In addition, this processing tank 10 may be installed in an underground space, and may be installed in a place (including the ground) partitioned from the underground space.
[0047]
Conventional wet scrubbers are widely used as large-capacity air purification devices, and it has been confirmed that dust and the like are efficiently collected. _X It is said that almost no hydrophobic substances such as water and hydrocarbons can be collected. However, since ozone water is sprayed in the present invention, these hydrophobic substances in contact with ozone water droplets are easily oxidized and dissolved in water by the strong oxidizing power of ozone, in other words, easily collected in the droplets. It changes to properties and is collected efficiently. Odor components are oxidized and deodorized with ozone, and microorganisms are killed by ozone.
[0048]
In the illustrated example, a filling contact layer 14 is provided in the processing tank 10. In the illustrated example, the filling contact layer 14 (also referred to as a contact bed) is formed by stacking a plurality of metal meshes. The part adheres to the surface so that more efficient gas-liquid contact is made. The filling contact layer 14 may use small pieces such as other pebbles of a wire mesh. However, in the example of FIG. In this invention, it is not suitable for use here because it is consumed when attached. Needless to say, the filling contact layer 14 may be of any other known type other than those described above.
[0049]
In the illustrated example, the filling contact layer 14 is provided above the first injection nozzle group 11a. However, the filling contact layer 14 may be provided on one or both of the upper and lower sides. The sprayed ozone water droplets are fine, and the ones that rise as a result of the air flow are collected in contact with the filled contact layer 14 having a large surface area, and drop into large droplets. It is said that it is suitable for use when the spray droplets are fine. Further, the filling contact layer 14 provided below the first injection nozzle group 11a is used so that spray droplets directly fall on it, and is used with a relatively large spray droplet size and a large spray amount. It is said to be suitable for the case. In the present invention, the oxidation with ozone water requires a certain reaction time (several seconds to several tens of seconds). The flow velocity of the airflow is slowed down, and the frequency of gas-liquid contact is increased. Since it is efficient to do this, it is desirable to adopt a method in which the filling contact layer 14 is disposed above the former first injection nozzle group 11a.
[0050]
In addition, the said filling contact layer 14 is similarly provided in the 2nd injection nozzle group 11b side in the example of illustration. The filling contact layer 14 is obliquely provided in the illustrated example, but this makes it easy for liquid droplets attached to the surface to form a liquid layer and move to the inner surface side of the processing tank 10, This is to make it flow down as a liquid layer.
[0051]
In the example shown in FIG. 1, a mist eliminator 15 is provided near the air outlet 13 of the processing tank 10. The mist eliminator 15 employs a collision plate system in the illustrated example, and a fine mist rising along with the air current collides and is collected, but has the same structure as the filling contact layer 14. Since the ozone does not flow frequently at this part, activated carbon may be used as a filler. If ozone should flow, the ozone should be decomposed by contact with the activated carbon. It may be made.
[0052]
Further, the invention according to claim 2 is characterized in that the second injection nozzle group 11b is located on the downstream side of the air flow from the first injection nozzle group 11a in the processing tank 10.
[0053]
That is, in the present invention, spray droplets to the airflow are performed in a plurality of stages. The first reason for the gas-liquid contact in multiple stages is to keep the ozone concentration of ozone water at a predetermined level. Ozone water can oxidize nitrogen smoothly unless the ozone concentration is above a certain level. As a result of the experiment, an ozone concentration of about 7 to 10 ppm is necessary, and when ozone water and non-ozone water are sprayed at the same place, both are mixed and the ozone concentration is lowered.
[0054]
In addition, the second purpose of spraying droplets to the airflow in multiple stages is that the ozone water is not effective for sterilization and deodorization unless the concentration is higher than a predetermined level, for example, E. coli is killed by 2-3 ppm ozone water, Bacteria with large antibiotics do not die unless they are ozone water of 5 ppm or more, and deodorization requires a concentration of 3 to 5 ppm or more. In the gas-liquid contact part for the purpose of sterilization and deodorization, ozone water can be contacted first. This is because it is advantageous.
[0055]
In addition, the third purpose of spraying droplets into the airflow in multiple stages is to use water effectively, so it is desirable to use water containing hydrogen bubbles, but when this water containing hydrogen bubbles comes into contact with ozone water, Ozone and hydrogen react violently, resulting in wasteful consumption of ozone. Therefore, this hydrogen bubbled water is used without being in contact with ozone water.
[0056]
Furthermore, the fourth purpose of spraying droplets into the air stream in multiple stages, particularly the purpose of the latter stage of spraying water containing hydrogen bubbles, is to capture the presence of hydrophobic substances in the air stream with a conventional mere wet scrubber. It is difficult to collect, because it is effective for collection to make it easy to be dissolved in water by ozone oxidation and to make gas-liquid contact in the next stage, and further from the ozone water mist and ozone water to the gas phase. This is to prevent ozone from reacting with hydrogen in the event that the ozone is leaked.
[0057]
In the example shown in FIG. 1, a vertical type is used for the treatment tank 10, but it is a matter of course that a horizontal type may be used when a sufficient height cannot be obtained in the storage space. In the invention of claim 3, the air is introduced into the treatment tank 10 in which the air in the underground space such as a tunnel provided with the air inlet 12 on the left and right ends and the air outlet 13 on the left and right ends is passed. The baffle plate 17 is provided at the bottom of the processing tank 10 so as not to block the drain water. The first injection nozzle group 11a is disposed on the air inlet 12 side of the baffle plate 17 and the air outlet 13 side. The second injection nozzle group 11b was housed in the container, and the treatment tank 10 was provided with a drain port 18 at the bottom.
[0058]
As described above, the use of the horizontal processing tank 10 is particularly suitable for installation in a tunnel in which there is not enough room in the height space and there is room in the length direction. This has the advantage that the processing space of the injection nozzle group 11a and the processing space of the second injection nozzle group 11b can be more reliably defined.
[0059]
That is, when the first injection nozzle group 11a and the second injection nozzle group 11b are provided vertically as in the "FIG. 1" embodiment, spraying is performed from the second injection nozzle group 11b by the filling contact layers 14 and 14 described above. It is possible to prevent the droplets from descending and entering the droplet spraying region of the first injection nozzle group 11a (for example, as described above, the droplets sprayed from the second injection nozzle group 11b are treated by the processing tank 10). However, if the spray amount of the droplets is large or the particle size of the spray droplets is large, the first spray nozzle group 11a and the second spray nozzle group 11b Both droplet spray areas may overlap, but if the both droplet spray areas are partitioned by the baffle plate 17 as in the present invention, the droplet spray areas can be more reliably distinguished.
[0060]
In addition, the said baffle plate 17 should just use a conventionally well-known thing, and in the example of illustration, it has stood up from the bottom face of the processing tank 10, and the upper side provided the predetermined space | interval with the upper surface of this processing tank 10. A partition 17a and an upper partition 17b which is suspended from the upper surface of the processing tank 10 and has a lower side provided with a predetermined interval between the bottom surface of the processing tank 10 and the lower partition 17a and the upper partition 17b are constant. Are in parallel with each other. One of the lower partition 17a and the upper partition 17b may be omitted, or three or more may be used.
[0061]
Therefore, the baffle plate 17 bends or meanders the flow path of the airflow, but at the same time may partition the bottom of the processing tank 10. When the bottom of the treatment tank 10 is partitioned, the drain of the acidic water sprayed from the first spray nozzle group 11a and the alkaline drain sprayed from the second spray nozzle group 11b are separately stored, and these are naturally stored. If it is discharged, the natural environment is damaged and the treatment process is complicated even if it is treated and drained. Therefore, in the present invention, the baffle plate 17 that does not block the passage of drain water is used so that both drains are mixed. . In order to prevent the passage of drain water, a through hole may be provided at the bottom of the baffle plate 17 or a slight gap may be provided between the lower side of the baffle plate 17 and the bottom surface of the treatment tank 10. Of course.
[0062]
In the “FIG. 5” embodiment, the filling contact layer 14 is provided between the lower partition 17a and the upper partition 17b.
[0063]
【The invention's effect】
The present invention is as described above, and since electrolysis is applied to the ozone generation source, ozone can be obtained from water that can be easily obtained even in underground spaces such as tunnels, and the apparatus is also extremely simple, small, and inexpensive. A space air purifier can be provided.
[0064]
Electrolysis with the solid electrolyte membrane 31 sandwiched may be at a low voltage of about 10 to 30 V, the DC voltage power supply 20 may be small, and an electrical short circuit accident may occur even when used in a subterranean space such as in a wet tunnel. It is possible to provide a tunnel air purification device that is difficult to generate.
[0065]
Furthermore, the present invention is easy to handle because the obtained ozone is immediately dissolved in water and is in a liquid phase, there is no leakage of ozone gas, and it is ozone water that is extremely safe even if it leaks. It is possible to provide an air purification device for an underground space that is extremely less than the case of handling gas phase ozone.
[0066]
Further, in the present invention, a conventionally known wet scrubber can be used for the treatment tank 10 and ozone water is used as spray water, so that denitration, deodorization and sterilization can be performed with a compact device, and hydrophobic substances can be efficiently used. It is possible to provide an air purification device for underground space that can be collected.
[0067]
Further, in the invention of "Claim 2", since the second injection nozzle group 11b is separately provided on the downstream side of the first injection nozzle group 11a, the object described in the items "0053" to "0056" can be achieved. Therefore, it is possible to provide an air purification device for underground space that can perform ozone oxidation more efficiently and as a result, can perform effective air purification.
[0068]
The invention of "Claim 3" is particularly suitable for installation in a tunnel because the treatment tank 10 has a horizontal shape, and further, the treatment space of the first injection nozzle group 11a and the treatment of the second injection nozzle group 11b. It is possible to provide an air purification device for an underground space that can more reliably demarcate the space and perform more efficient ozone oxidation (denitration), dust removal, sterilization, and deodorization.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an embodiment of a tunnel air purification apparatus of the present invention.
FIG. 2 is a longitudinal sectional view of an ozone water production section used in the present invention.
FIG. 3 is a plan view of a lath net used in the present invention.
FIG. 4 is a partially enlarged sectional view of an ozone water production unit used in the present invention.
FIG. 5 is a longitudinal sectional view of a main part of another embodiment.
[Explanation of symbols]
10 treatment tank
11a First injection nozzle group
11b First injection nozzle group
12 Air inlet
13 Air outlet
17 Baffle plate
18 Drainage port
30 Ozone water generation cell
31 Solid electrolyte membrane
32 Anode electrode
33 Cathode electrode
34 Anode side jacket
35 Cathode side jacket
36a Water inlet
36b Water inlet
37a Water outlet
37b Water outlet
38 DC voltage electricity
40a Water delivery pipe
40b Water delivery pipe

Claims (3)

An anode electrode (32) made of a porous material having a predetermined opening ratio made of a metal having an ozone generating catalyst function is superimposed on one surface of the solid electrolyte membrane (31), and a porous material having a predetermined opening ratio on the other surface The formed cathode electrode (33) is overlapped, and the anode side jacket (34) and the cathode side jacket (35) covering the anode electrode (32) and the cathode electrode (33) are respectively provided with water inlets (36a, 36b). An ozone water generation cell (30) is configured by providing water outlets (37a, 37b),
The anode electrode (32) and the cathode electrode (33) are connected to a DC voltage power source (38), the water inlets (36a, 36b) are connected to water supply pipes (40a, 40b), and the anode side jacket is connected. The water outlet (37a) of (34) is connected to the first outlet nozzle group (11a) provided in the treatment tank (10) through which air in the underground space such as a tunnel flows, 37b) is an air treatment device for an underground space connected to the second injection nozzle group (11b) provided in the treatment tank (10). The underground according to claim 1, wherein the second injection nozzle group (11b) is located on the downstream side of the air flow from the first injection nozzle group (11a) in the treatment tank (10). Air purification device for space. An anode electrode (32) made of a porous material having a predetermined opening ratio made of a metal having an ozone generating catalyst function is superimposed on one surface of the solid electrolyte membrane (31), and a porous material having a predetermined opening ratio on the other surface The formed cathode electrode (33) is overlapped, and the anode side jacket (34) and the cathode side jacket (35) covering the anode electrode (32) and the cathode electrode (33) are respectively provided with water inlets (36a, 36b). An ozone water generation cell (30) is configured by providing water outlets (37a, 37b),
An air flow path is provided in a treatment tank (10) through which air flows in an underground space such as a tunnel provided with an air inlet (12) on one side of the left and right sides and an air outlet (13) on the other side of the left and right sides. A baffle plate (17) that is bent and does not block the passage of drain water is provided at the bottom of the treatment tank (10), and the first injection nozzle group (11a) is provided on the air inlet (12) side of the baffle plate (17). The second injection nozzle group (11b) is housed on the air outlet (13) side, and a drain port (18) is provided at the bottom of the treatment tank (10).
The anode electrode (32) and the cathode electrode (33) of the ozone water generation cell (30) are connected to a DC voltage power source (38), and water feed pipes (40a, 40b) are connected to the water inlets (36a, 36b). The water outlet (37a) of the anode side jacket (34) is connected to the first injection nozzle group (11a), and the water outlet (37b) of the cathode side jacket (35) is connected to the second injection nozzle group (11b). An air treatment device for underground space connected to each other.

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