JP2004141697A - Wastewater treatment equipment and manufacturing method of soil improving material using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wastewater treatment equipment reduced in equipment investment usable even as a small-scaled wastewater treatment equipment, excellent in general-purpose properties, capable of extremely efficiently performing the oxidative decomposition of organic matter in wastewater, the oxidation and precipitation of metal ions and the deodorization, decoloration, sterilization or the like of wastewater, capable of obtaining clean treated water having contaminants far less than a wastewater standard and capable of enhancing the concentration properties of sludge to sharply reduce the production quantity of solid waste, and a manufacturing method of a soil improving material using the same. <P>SOLUTION: The wastewater treatment equipment is equipped with a reaction tank having a wastewater inflow port and storing wastewater, a reaction tank first communication part having a wastewater suction port formed to one end, having a wastewater injection port formed at the other end and communicating with the reaction tank, a reaction tank first pump arranged to the reaction tank first communication part to circulate wastewater and the reaction tank ozone gas supply part connected to the reaction tank first communication part on the upstream side of the reaction tank first pump to supply an ozone gas into the system. <P>COPYRIGHT: (C)2004,JPO

Description

【００１４】
オゾンに加え、紫外線、過酸化水素水、酸化チタン等の金属酸化触媒等を排水に照射、添加若しくは接触等させることにより、有機物等の分解をより促進させるとともに環境ホルモン，ダイオキシン，有機塩素化合物等の環境汚染物質の分解を促進させることができる。
【００１５】
請求項２に記載の発明は、請求項１に記載の排水処理装置であって、前記反応槽第１連通部に微細気泡発生手段が配設された構成を有している。
この構成により、請求項１で得られる作用に加え、以下のような作用が得られる。
（１）反応槽第１連通部に微細気泡発生手段が配設されているので、オゾンガスを微細気泡に含有させて排水中に供給することができ、オゾンの排水中の滞在時間を長くすることができるとともに排水に対するオゾンの溶解度を増加させて酸化分解反応を活発化させることができ、さらに排水中の汚濁物質が微細気泡に付着して浮上分離され排水処理効率を高めることができる。
【００１６】
ここで、微細気泡発生手段としては、反応槽第１ポンプの下流側の反応槽第１連通部に配設されたエゼクタを備えたものを用いることができる。これにより、排水注入口から噴射される排水の噴流による負圧によりエゼクタからオゾンガスを吸引し、気体流に作用する剪断作用によりオゾンを含有する微細気泡を発生させることができる。また、反応槽第１連通部に配設された渦流タービンポンプ（ニクニ社製）等の上流側に反応槽オゾンガス供給部を設け、該ポンプで渦流を発生させながらオゾンガスを排水に拡散させ気液を圧送することができる。この場合は、反応槽第１ポンプと微細気泡発生手段とを兼用させることができる。これにより、高濃度のオゾンガスを微細気泡として排水中に溶存させることができるとともに装置構成を簡単にできる。また、反応槽第１ポンプの上流側に反応槽オゾンガス供給部を設け、該ポンプの下流側の反応槽第１連通部に微細気泡発生装置（バブルタンク社製）を配設することができる。これにより、オゾンを含有する排水中の気泡を著しく微細化させることができる。なお、微細気泡発生手段は、これらに限定するものではなく、排水中の気泡を微細化させることができるものであれば用いることができる。
【００１７】
微細気泡の平均の気泡径としては、０．０１〜２００μｍ好ましくは０．５〜５０μｍが好適である。平均の気泡径が０．５μｍより小さくなるにつれ微細気泡の発生手段が複雑化する傾向がみられ、５０μｍより大きくなるにつれ、排水の粘度にもよるが、排水中に供給した微細気泡が直ちに浮上し排水中に滞留する時間が短く処理効率が低下する傾向がみられるため好ましくない。特に、０．０１μｍより小さくなるか２００μｍより大きくなるとこれらの傾向が著しくなるため、いずれも好ましくない。なお、気泡径の測定は、水面にガラス板を置き水中の気泡をデジタルカメラで撮影し画像処理を行い算出することができる。
【００１８】
本発明の請求項３に記載の発明は、請求項１又は２に記載の排水処理装置であって、一端が前記反応槽の所定部に連通され他端が前記反応槽の上部に連通された反応槽第２連通部と、前記反応槽第２連通部に配設され排水を循環させる反応槽第２ポンプと、前記反応槽第２連通部の他端に接続された消泡ノズルと、を備えた構成を有している。
この構成により、請求項１又は２で得られる作用に加え、以下のような作用が得られる。
（１）反応槽第２連通部と、反応槽第２連通部に配設された反応槽第２ポンプと、反応槽第２連通部に接続された消泡ノズルと、を備えているので、注入された微細気泡に付着して浮上分離した汚濁物質に消泡ノズルから排水を吹き付けて消泡させ、汚濁物質を再び排水中に懸濁させることができる。また、排水の流滴等を反応槽上部のオゾンガス層に繰り返し接触させることができる。これによって、汚濁物質がオゾンガスに繰り返し接触し汚濁物質の分解が促進され排水処理効率を高めることができる。
【００１９】
本発明の請求項４に記載の発明は、請求項１乃至３の内いずれか１に記載の排水処理装置であって、前記反応槽に配設された冷却装置及び／又は前記反応槽に覆設された断熱部材を備えた構成を有している。
この構成により、請求項１乃至３の内いずれか１で得られる作用に加え、以下のような作用が得られる。
（１）反応槽が冷却装置や断熱部材を備えているので、気温の高い夏季においても排水の水温を低く保つことができ、オゾンの溶解度を高め酸化分解反応等の反応を向上させ排水処理効率を向上させることができる。水に対するオゾンの溶解度は水温が低いほど大きくなるからである。
【００２０】
ここで、冷却装置としては、（１）反応槽の外部に冷却用ジャケットを配設し内部に冷却水や冷風等を流したり氷等を蓄えて冷却するもの、（２）反応槽の外部に放熱用フィンを配設して空冷することによって冷却するもの、（３）反応槽の内部に冷却ガス噴射ノズルを配設し冷却されたガスを排水内に注入することによって排水を冷却するもの等のいずれか１以上を用いることができる。
【００２１】
本発明の請求項５に記載の発明は、請求項１乃至４の内いずれか１に記載の排水処理装置であって、前記反応槽内の排水の水温が、２８℃以下好ましくは２０℃以下に維持された構成を有している。
この構成により、請求項１乃至４の内いずれか１で得られる作用に加え、以下のような作用が得られる。
（１）反応槽内の排水の水温が低温に維持されているので、オゾンの溶解度が低下するのを防止し安定した排水処理効率を得ることができる。
【００２２】
ここで、反応槽内の排水の水温が２０℃より高くなるにつれ水に対するオゾンの溶解度が低下しオゾンによる酸化分解反応が乏しくなり排水処理効率が低下する傾向がみられるため好ましくない。特に、水温が２８℃より高くなると、この傾向が著しくなるので好ましくない。なお、排水の水温の下限は、排水が凍りつかない水温であればよいため、０℃より高い温度に維持されていればよい。但し、反応槽等の内部が常に流動でき凍りつかない状態であれば、０℃以下の水温でも構わない。
【００２３】
本発明の請求項６に記載の発明は、請求項１乃至５の内いずれか１に記載の排水処理装置であって、前記反応槽の底部若しくはその側部の所定部に接続された汚泥スラリー排出部及び／又は前記反応槽の上方の所定部に接続された排泡部を備えた構成を有している。
この構成により、請求項１乃至５の内いずれか１で得られる作用に加え、以下のような作用が得られる。
（１）汚泥スラリー排出部や排泡部を備えているので、排水のオゾン処理を行った後に反応槽の底部に沈降した汚泥や微細気泡に付着した汚泥を処理水とは別に反応槽の外部に排出することができ、排水中の汚泥を分離濃縮することができる。
【００２４】
本発明の請求項７に記載の発明は、請求項６に記載の排水処理装置であって、前記汚泥スラリー排出部及び／又は前記排泡部に接続された処理槽と、一端に汚泥吸引口が他端に汚泥注入口が形成され前記処理槽と連通する処理槽第１連通部と、前記処理槽第１連通部に配設され汚泥を循環させる処理槽第１ポンプと、前記処理槽第１ポンプの上流側の前記処理槽第１連通部に接続された処理槽オゾンガス供給部と、を備えた構成を有している。
この構成により、請求項６で得られる作用に加え、以下のような作用が得られる。
（１）汚泥スラリー排出部や排泡部に接続された処理槽を備えているので、反応槽から排出された汚泥を処理槽でオゾンを用いてさらに酸化分解させることができ、汚泥等の固形廃棄物の減容を図ることができる。
（２）反応槽の底部に沈降した汚泥や微細気泡に付着して浮上分離した汚泥を処理槽に導いて汚泥を濃縮させ減容させることができるので、反応槽と処理槽で並行して排水処理を進めることができ作業性に優れる。
【００２５】
ここで、処理槽第１連通部には、請求項２で説明した微細気泡発生手段を配設することができる。これにより、請求項２に記載の作用と同様の作用が得られる。
【００２６】
本発明の請求項８に記載の発明は、請求項１乃至７の内いずれか１に記載の排水処理装置であって、前記排水流入口に接続された溶解槽と、前記溶解槽に接続され排水を前記溶解槽に流入させる排水流入路と、前記排水流入路に配設され排水を圧送するとともに前記溶解槽内を加圧する圧送ポンプと、前記圧送ポンプの上流側の前記排水流入路に接続された溶解槽オゾンガス供給部と、を備えた構成を有している。
この構成により、請求項１乃至７の内いずれか１で得られる作用に加え、以下のような作用が得られる。
（１）排水流入口に接続された溶解槽と、排水流入路に配設され排水を圧送するとともに溶解槽内を加圧する圧送ポンプと、排水流入路に接続された溶解槽オゾンガス供給部と、を備えているので、溶解槽内で排水が加圧されオゾンを過飽和状態で溶解させることができオゾンによる酸化分解効率を高めることができる。
（２）溶解槽内で加圧されてオゾンが過飽和状態で溶解した排水が大気圧下の反応槽に放出されるので、溶解したオゾンが微細気泡として多量に出現し汚濁物質の浮上分離及び酸化分解反応が直ちに行われ排水処理時間を著しく短縮することができ作業性に優れる。
【００２７】
ここで、圧送ポンプは溶解槽を０．２〜１ＭＰａの圧力で加圧するのが好ましい。圧力が０．２ＭＰａより小さくなるにつれ圧力が小さいためオゾンの溶解度の増加量が少なく酸化分解効率の増加効果を高め難い傾向がみられ、圧力が１ＭＰａより大きくなるにつれ耐圧性を高めるため溶解槽が大型化し設備負荷が増大する傾向がみられるため好ましくない。
なお、排水流入路には、請求項２で説明した微細気泡発生手段を配設することができる。これにより、請求項２に記載の作用と同様の作用が得られる。
【００２８】
本発明の請求項９に記載の土壌改良材の製造方法は、請求項１乃至８の内いずれか１に記載の排水処理装置を用い前記反応槽に貯留された排水を循環させながらオゾンガスを供給して排水をオゾン処理するオゾン処理工程と、前記オゾン処理工程で処理された処理水と汚泥スラリーとを前記反応槽から排出する排出工程と、排出された前記処理水及び／又は前記汚泥スラリーを脱水処理して土壌改良材として単独で若しくは配合して用いる固形分を採取する脱水処理工程と、を備えた構成を有している。
この構成により、以下のような作用が得られる。
（１）オゾン処理された処理水や汚泥スラリーを脱水処理して固形分を採取するので、大腸菌等の細菌類がなく無菌で衛生的な土壌改良材を製造することができる。また、処理水等の溶存酸素量が著しく高いので、固形分の好気性が高く土壌菌等が繁殖し易く作物の栽培に適した土壌改良材を製造することができる。オゾンの酸化作用によって有害細菌類が死滅するとともにオゾンが分解した酸素で酸化されているからである。また、処理水を脱水処理して採取された固形分からは、銅，カドミウム，亜鉛等の土壌汚染物質の含有量の少ない土壌改良材を製造することができる。オゾン処理によって排水中の土壌汚染物質の金属イオンが酸化され析出し処理水から分離されるので処理水に含まれず、そのため処理水を脱水処理されて採取された固形分中にも含まれないからである。
（２）処理水や汚泥スラリーを固液分離して得られた固形分は、有機物が分解され窒素やリン等を含有するので作物の栽培に適している。
（３）オゾンの酸化力によって好気性の土質に変化しているので、もみがら，わら等の有機物を加えた後にコンポスト化することも容易であり汎用性に優れる。
【００２９】
【発明の実施の形態】
以下、本発明の一実施の形態を、図面を参照しながら説明する。
（実施の形態１）
図１は実施の形態１における排水処理装置の模式図である。
図中、１は実施の形態１における排水処理装置、２は産業用廃水，下水及びし尿等の排水が集水されて貯留された排水貯留槽、３は排水貯留槽２内に浸漬され集水された排水を揚水する排水ポンプ、４は排水ポンプ３に一端が接続された排水供給路、５は排水供給路４に配設された排水供給弁、６は排水が貯留される反応槽、７は反応槽６の下部側に形成され排水供給路４の他端側が接続された排水流入口、８は反応槽６の上方及び下方と連通する反応槽第１連通部、９は反応槽第１連通部８の一端に形成され反応槽６に供給された排水を吸引する排水吸引口、１０は反応槽第１連通部８の他端に形成され排水吸引口９から吸引された排水を反応槽６内に注入する排水注入口、１１は反応槽第１連通部８に配設され排水を排水吸引口９から排水注入口１０へと循環する反応槽第１ポンプである。本実施の形態においては反応槽第１ポンプ１１として渦流タービンポンプ（ニクニ社製）を用い、これを微細気泡発生手段として兼用した。
１２は反応槽第１ポンプ１１の上流側の反応槽第１連通部８に接続され酸素を無声放電式のオゾナイザー等によりオゾンガス化し空気，酸素とともにオゾン若しくは酸素とともにオゾンを系内に供給する反応槽オゾンガス供給部、１３はゼオライト等を用いて空気からオゾンの原料となる高濃度の酸素を製造し反応槽オゾンガス供給部１２に供給する酸素ガス発生部、１４は一端が反応槽６の下方に連通され他端が反応槽６の上方に連通された反応槽第２連通部、１５は反応槽第２連通部１４に配設され排水を循環する反応槽第２ポンプ、１６は反応槽第２連通部１４の他端に接続され反応槽６の上部に配設された消泡ノズル、１７は反応槽６の底部に接続された汚泥スラリー排出部、１８は汚泥スラリー排出部１７に配設された排泥弁、１９は汚泥スラリー排出部１７に配設された排泥ポンプ、２０は汚泥スラリー排出部１７に配設された濾過装置等の固液分離装置、２１は反応槽６の上方の所定部に接続された排泡部、２２は排泡部２１に配設された排泡ポンプ、２３は反応槽６の所定部に接続された処理水排出部、２４は処理水排出部２３に配設された処理水排出弁、２５は処理水排出部２４に配設された処理水排出ポンプ、２６は処理水排出部２３に配設された濾過装置等の固液分離装置、２７は反応槽６の上部に接続された排ガス管、２８は排ガス管２７に配設され排ガス中のオゾン濃度を測定するオゾン濃度検出装置、２９は排ガス管２７に配設され排ガス中のオゾンを吸着して分解する活性炭等を含有する排オゾン処理装置である。
【００３０】
以上のように構成された実施の形態１における排水処理装置について、以下その使用方法を説明する。
オゾン処理工程において、始めに、排水供給路４に配設された排水供給弁５を開弁した後、排水ポンプ３を駆動し排水貯留槽２に集水された排水を反応槽６に供給する。排水の水面の高さが排水吸引口９よりも高い位置まで達した後、排水ポンプ３を停止するとともに排水供給弁５を閉止する。
次に、反応槽第１ポンプ１１を駆動して排水を循環するとともに酸素ガス発生部１３，反応槽オゾンガス供給部１２を駆動して、所定濃度のオゾンガスを平均粒径０．０１〜２００μｍの微細気泡に含有させて排水中に溶存させ排水注入口１０から反応槽６内に注入する。これにより、排水中の汚濁物質が微細気泡に付着して浮上分離し反応槽６の上方に無数の汚濁物質が付着した泡が現れる。このとき、系内に供給するオゾンガス濃度は、排ガス管２７に配設されたオゾン濃度検出装置２８の検出値が所定の基準値以下になるように最適量に調整する。
次に、反応槽第２ポンプ１５を駆動して排水を消泡ノズル１６から噴射する。これにより、反応槽６の上方に発現した泡が消されて泡に付着していた汚濁物質は再び排水中に懸濁する。これを繰り返すことによって、オゾンによる排水中の汚濁物質の酸化分解が繰り返し行われる。
反応槽６内に所定濃度のオゾンガスを所定時間注入した後、反応槽第１ポンプ１１，反応槽オゾンガス供給部１２，酸素ガス発生部１３を停止する。次いで、排出工程において、排泥弁１８を開弁するとともに排泥ポンプ１９を駆動して反応槽６の底部に沈降した汚泥を汚泥スラリーとして汚泥スラリー排出部１７から反応槽６の外部に排出する。さらに、排泡ポンプ２２を駆動して排泡部２１から汚濁物質が付着した泡を反応槽６の外部に排出する。次いで、処理水排出弁２４を開弁した後、処理水排出ポンプ２５を駆動して、処理水排出部２３から汚泥スラリーや泡が除去された処理水を反応槽６から排出する。
脱水処理工程において、処理水は固液分離装置２６によって固形分が除去された後、河川等に放流される。固液分離装置２６によって分離され脱水処理された固形分は、必要に応じて施肥や発酵，水分量調整等の処理がなされ土壌改良材として利用することができる。また、汚泥スラリー１７から排出された汚泥スラリーは固液分離装置２０で脱水処理されて固形分が採取される。この固形分も土壌改良材として用いることができる。
【００３１】
以上のように、実施の形態１における排水処理装置は構成されているので、以下のような作用が得られる。
（１）排水が貯留される反応槽と、反応槽と連通する反応層第１連通部と、反応層第１連通部に配設された反応槽第１ポンプと、オゾンガスを系内に供給する反応槽オゾンガス供給部と、を備えているので、反応槽，反応槽第１連通部内の排水にオゾンガスを微細気泡にして拡散して供給することにより、オゾンの酸化力によって排水中の有機物の酸化分解、金属イオンの酸化・析出、排水の脱臭，脱色，殺菌等が行われ排水基準を大幅に下回る清浄な処理水を得ることができる。
（２）オゾンガスを反応槽第１ポンプの上流側に供給するので、供給されたオゾンガスを反応槽第１ポンプのインペラにより排水中に微細気泡として拡散させることができる。また、反応層第１連通部を備え排水を循環させるので、排水が反応槽内で撹拌されて排水が微細気泡のオゾンガスと同伴し繰り返しオゾンガスと接触し酸化分解や殺菌効率を高めることができる。
（３）オゾンガスを平均粒径０．０１〜２００μｍの微細気泡に含有させて排水中に供給するので、オゾンの排水中の滞在時間を長くすることができるとともに排水中の溶解度を増加させて酸化分解反応を活発化させることができ、さらに排水中の汚濁物質に付着して浮上分離させることができ排水処理効率を高めることができる。
（４）オゾンの酸化分解によって、汚泥中のタンパク質等の有機性物質等が酸化分解されて可溶化されるとともに、粘性を発現するタンパク質等の分解により汚泥の粘性が低下するので、汚水中の泥状物の濃縮性を向上させ汚泥の発生量を大幅に減少させることができる。
（５）オゾンガスを用いて酸化分解するので、流入水質や水量の変動、気候等の環境条件の変動に対しても、安定して水質の良好な処理水を得ることができる。
（６）オゾンを用いた酸化分解によって酸素が生成されるので、周辺環境に二次的な環境汚染を引き起こさず、また処理水や汚泥はオゾンの強力な酸化力によって殺菌され衛生的である。さらに、処理水はオゾンの酸化力によって好気性の水質に変化しているので、河川等へ放流することはもちろん、生物処理の前処理として生物分解槽に注入することもでき応用性が高い。
（７）装置の構成が簡単なので、建設費や運転管理費を少なくすることができ設備負荷を小さくすることができ、大都市近郊や工場等の大規模な排水処理だけでなく、中小都市や農山村地域において汚濁水発生源若しくは小集落ごとに排水処理を行う小規模排水処理装置として用いることができる。また、設置に多くの敷地面積を要さないので、車両等に搭載して汚濁水発生源や小集落等を巡回する移動式の排水処理装置としても用いることができ汎用性に優れる。
（８）反応槽第２連通部と、反応槽第２連通部に配設された反応槽第２ポンプと、反応槽第２連通部に接続された消泡ノズルと、を備えているので、注入された微細気泡に付着して浮上分離した汚濁物質に消泡ノズルから排水を吹き付けて消泡させ、汚濁物質を再び排水中に懸濁させることができる。これによって、汚濁物質がオゾンガスに繰り返し接触し汚濁物質の分解が促進され排水処理効率を高めることができる。
（９）汚泥スラリー排出部や排泡部を備えているので、排水のオゾン処理を行った後に反応槽の底部に沈降した汚泥や微細気泡に付着した汚泥を処理水とは別に反応槽の外部に排出することができ、排水中の汚泥を分離濃縮することができる。
（１０）酸素ガス発生装置が反応槽オゾンガス供給部に接続されているので、強制的に空気中の酸素濃度を高めて高濃度の酸素を反応槽オゾンガス供給部に供給することによりオゾンガス濃度を高めることができる。これにより、反応槽，反応槽第１連通部に供給するオゾン発生量を高め排水の酸化分解効率を高めることができる。また、汚濁水の含有有機物量に応じてオゾンガスを適正量発生させることができ、処理効率を高めることができる。
（１１）排ガス管にオゾン濃度検出装置が配設されているので、排ガス中のオゾンガス濃度がほぼゼロになるように反応槽オゾンガス供給部から発生するオゾンガス濃度を調整して、酸化反応に必要な最適量のオゾンを排水中に供給することができオゾンを排水処理に無駄なく利用することができる。
【００３２】
本実施の形態においては、反応槽第１ポンプ１１に渦流タービンポンプを用い、これを微細気泡発生手段として用いる場合を説明したが、これに代えて、反応槽第１ポンプ１１の下流側の反応槽第１連通部８にエゼクタを備えた微細気泡発生手段８ａを配設する場合もある。これにより、排水注入口１０から噴射される排水の噴流による負圧によりオゾンを吸引し、気体流に作用する剪断作用により排水中に微細気泡を発生させることができる。また、反応槽第１ポンプの下流側に微細気泡発生装置（バブルタンク社製）を配設し、より微細な気泡径を有する微細気泡を発生させることができる。
また、反応槽第１連通部８の一端に形成された排水吸引口９が反応槽６の上方と連通する場合について説明したが、排水吸引口９を反応槽６の下方乃至上方の所定部と連通させ反応槽６内の排水を吸引させる場合もある。また、排水注入口１０や排水吸引口９を反応槽６の複数箇所と連通させることもできる。これにより、排水の循環効率を高めることができる。
【００３３】
（実施の形態２）
図２は本発明の実施の形態２における排水処理装置の模式図である。なお、実施の形態１と同様のものは、同じ符号を付して説明を省略する。
図中、３０は実施の形態２における排水処理装置、３１は反応槽６の側壁に配設され反応槽６内の排水を２８℃以下好ましくは２０℃以下の水温に維持する冷却装置としての冷却用ジャケット、３２は汚泥スラリー排出部１７，排泡部２１が接続された処理槽、３３は処理槽３２の上方及び下方と連通する処理槽第１連通部、３３ａは反応槽第１連通部３３に配設されたエゼクタを備えた微細気泡発生手段、３４は処理槽第１連通部３３の一端に形成され処理槽３２に供給された汚泥スラリーを吸引する汚泥吸引口、３５は処理槽第１連通部３３の他端に形成され汚泥吸引口３４から吸引された汚泥スラリーを処理槽３２内に注入する汚泥注入口、３６は処理槽第１連通部３３に配設され汚泥スラリーを汚泥吸引口３４から汚泥注入口３５へと循環する処理槽第１ポンプ、３７は処理槽第１ポンプ３６の上流側の処理槽第１連通部３３に配設された微細気泡発生手段３３ａに接続され酸素を無声放電式のオゾナイザー等によりオゾンガス化し系内に空気，酸素とともにオゾン若しくは酸素とともにオゾンを供給する処理槽オゾンガス供給部、３８はゼオライト等を用いて空気からオゾンの原料となる高濃度の酸素を製造し処理槽オゾンガス供給部３７に供給する酸素ガス発生部、３９は一端が処理槽３２の下方に連通され他端が処理槽３２の上方に連通された処理槽第２連通部、４０は処理槽第２連通部３９に配設され汚泥を循環する処理槽第２ポンプ、４１は処理槽第２連通部３９の他端に接続され処理槽３２の上部に配設された消泡ノズル、４２は処理槽３２に接続されスラリー状の汚泥を排出する第１汚泥排出部、４３は第１汚泥排出部４２に配設された第１汚泥排出弁、４４は処理槽３２の底部に接続されスラリー状の汚泥を排出する第２汚泥排出部、４５は第２汚泥排出部４４に配設された第２汚泥排出弁、４６は第１汚泥排出部４２と第２汚泥排出部４３に接続された汚泥排出部、４７は汚泥排出部４６に配設された汚泥排出ポンプ、４８は汚泥排出部４６に配設された濾過装置等の固液分離装置、４９は処理槽３２の上部に接続された排ガス管、５０は排ガス管４９に配設され排ガス中のオゾン濃度を測定するオゾン濃度検出装置、５１は排ガス管４９に配設され排ガス中のオゾンを吸着して分解する活性炭等を含有する排オゾン処理装置である。
実施の形態２においても実施の形態１と同様に、エゼクタを備えた微細気泡発生手段３３ａに代えて、処理槽第１ポンプ３６として渦流タービンポンプ等を用い、オゾンを微細気泡として汚泥注入口３５から発生させる場合もある。これにより、オゾンを含有する微細気泡の平均の気泡径を０．０１〜２００μｍにすることができる。
【００３４】
実施の形態２における排水処理装置が実施の形態１と異なる点は、反応槽６に冷却装置としての冷却用ジャケット３１が配設されている点、汚泥スラリー排出部１７及び排泡部２１に接続された処理槽３２を備え、処理槽３２が、処理槽第１ポンプ３６と処理槽オゾンガス供給部３７の配設された処理槽第１連通部３３と、消泡ノズル４１が接続された処理槽第２連通部３９と、を備えている点である。
処理槽３２で処理された排泡や汚泥スラリーは、汚泥排出ポンプ４７を駆動することによって第１汚泥排出部４２及び第２汚泥排出部４４から処理槽３２の外部へ排出され、固液分離装置４８によって汚泥スラリー等から固形分が採取される。採取された固形分は土壌改良材として用いることができる。
【００３５】
以上のように、実施の形態２における排水処理装置は構成されているので、実施の形態１に記載の作用に加え、以下のような作用が得られる。
（１）反応槽が冷却装置を備えているので、気温の高い夏季においても排水の水温を低く保つことができ、オゾンの溶解度を高め酸化分解反応等の反応を向上させ排水処理効率を向上させることができる。水に対するオゾンの溶解度は水温が低いほど大きくなるからである。
（２）汚泥スラリー排出部や排泡部に接続された処理槽を備えているので、汚泥スラリーを処理槽でオゾンを用いて酸化分解させることができ、さらに汚泥等の固形廃棄物の減容を図ることができる。
（３）反応槽の底部に沈降した汚泥や微細気泡に付着して浮上分離した汚泥を処理槽に導いて汚泥を濃縮させ減容させることができるので、反応槽と処理槽で並行して排水処理を進めることができ作業性に優れる。
【００３６】
なお、本実施の形態においては、処理槽第１連通部３３の一端に形成された汚泥吸引口３４が処理槽３２の上方と連通する場合について説明したが、汚泥吸引口３４を処理槽３２の下方乃至上方の所定部と連通させ処理槽３２内の汚泥スラリーを吸引させる場合もある。これにより、処理槽３２内に貯留された汚泥スラリーの量が少ないときでも処理槽第１連通部３３で汚泥スラリーを循環させてオゾン処理を行うことができ操作性に優れる。
【００３７】
（実施の形態３）
図３は本発明の実施の形態３における排水処理装置の模式図である。なお、実施の形態１と同様のものは、同じ符号を付して説明を省略する。
図中、６０は実施の形態３における排水処理装置、６１は一端が排水ポンプ３に接続され排水貯留槽２に貯留された排水が流れる排水流入路、６２は排水流入路６１に配設された排水流入弁、６３は排水流入弁６１の下流側の排水流入路６１に配設され排水を圧送する圧送ポンプ、６４は圧送ポンプ６３の上流側の排水流入路に接続され酸素を無声放電式のオゾナイザー等によりオゾンガス化し空気，酸素とともにオゾン若しくは酸素とともにオゾンを系内に供給する溶解槽オゾンガス供給部、６５はゼオライト等を用いて空気からオゾンの原料となる高濃度の酸素を製造し溶解槽オゾンガス供給部６４に供給する酸素ガス発生部、６６は排水流入路６１の他端が接続された溶解槽、６７は一端が溶解槽６６に接続され他端が反応槽６の排水流入口７に接続された連通部、６８は連通部６７に配設された連通弁、６９は連通弁６８より下流側の連通部６７に配設された排水輸送ポンプ、７０は溶解槽６６に配設された冷却装置としての冷却用ジャケット、７１は反応槽６に覆設された断熱部材、７２は冷却ガスを発生する冷却装置としての冷却ガス発生部、７３は溶解槽７０の内部の下部側に配設された冷却装置としての冷却ガス噴射ノズルである。
なお、本実施の形態においても実施の形態１乃至２と同様に、排水流入路６１にエゼクタ（図示しない）を有する微細気泡発生手段や、圧送ポンプ６３として微細気泡発生手段として兼用できる渦流タービンポンプ等を用い、オゾンを微細気泡として発生させることができる。これにより、オゾンを含有する微細気泡の平均の気泡径を０．０１〜２００μｍにすることができる。
【００３８】
以上のように構成された実施の形態３における排水処理装置について、以下その使用方法を説明する。
始めに、連通部６７に配設された連通弁６８を閉止し排水流入路６１に配設された排水流入弁６２を開弁した後、排水ポンプ３を駆動し排水貯留槽２に集水された排水を揚水する。次いで、圧送ポンプ６３を駆動するとともに酸素ガス発生部６５，溶解槽オゾンガス供給部６４を駆動して、オゾンを含有する微細気泡が溶解した排水を排水流入路６１から溶解槽６６内に圧送し、微細気泡が溶解した排水を０．２〜１ＭＰａの圧力で所定時間加圧する。さらに、オゾンの溶解度を高めるために冷却用ジャケット７０を用いて溶解槽６６を冷却する。
所定時間が経過した後、圧送ポンプ６３，酸素ガス発生部６５，溶解槽オゾンガス供給部６４を停止するとともに連通弁６８を開弁し、さらに排水輸送ポンプ６９を駆動することによって、溶解槽６６内の排水を反応槽６内へ輸送する。これにより、溶解槽６６内で加圧されてオゾンが過飽和状態で溶解した排水を大気圧下の反応槽６に放出させる。このとき、溶存していた微細気泡が多量に反応槽６内に出現し汚濁物質の浮上分離が行われる。反応槽６内の排水の水面の高さが排水吸引口９よりも高い位置まで達した後、排水輸送ポンプ６９を停止するとともに連通弁６８を閉止する。
次いで、反応槽第１ポンプ１１を駆動して排水を循環するとともに酸素ガス発生部１３，反応槽オゾンガス供給部１２を駆動して、オゾンを含有する微細気泡を排水注入口１０から反応槽６内に注入し、反応槽６内でオゾンによる排水処理を行う。排水の水温が高い場合は、反応槽６内の排水中のオゾンの溶解度を高めるため冷却ガス噴射ノズル７３から冷却ガスを排水中に注入し排水の水温を２８℃以下好ましくは２０℃以下の低温に維持する。
これ以後の排水処理装置の使用方法は、実施の形態１で説明したものと同様なので説明を省略する。
【００３９】
以上のように、実施の形態３における排水処理装置は構成されているので、実施の形態１に記載の作用に加え、以下のような作用が得られる。
（１）排水流入口に接続された溶解槽と、排水流入路に配設され排水を圧送するとともに溶解槽内を加圧する圧送ポンプと、排水流入路に接続し排水に供給される微細気泡が含有するオゾンガスを発生する溶解槽オゾンガス供給部と、を備えているので、溶解槽内で排水が加圧されオゾンを過飽和状態で溶解させることができオゾンによる酸化分解効率を高めることができる。
（２）溶解槽内で０．２〜１Ｐａの圧力で加圧されてオゾンが過飽和状態で溶解した排水が大気圧下の反応槽に放出されるので、溶解したオゾンが微細気泡として多量に出現し汚濁物質の浮上分離及び酸化分解反応が直ちに行われ排水処理時間を著しく短縮することができ作業性に優れる。
（３）反応槽や溶解槽が冷却装置や断熱部材を備えているので、気温の高い夏季においても排水の水温を低く保つことができ、オゾンの溶解度が低下して酸化分解反応が乏しくなり排水処理効率が低下するのを防止することができる。
【００４０】
（実施の形態４）
図４は本発明の実施の形態４における排水処理装置の模式図である。なお、実施の形態１と同様のものは、同じ符号を付して説明を省略する。
図中、８０は実施の形態４における排水処理装置、８１は排水ポンプ３が一端に接続された排水供給路、８２は排水供給路８１が複数本に分岐され他端が複数の排水処理装置１に接続された分岐供給路、８３は分岐供給路８２に配設された分岐供給弁、８４は排水処理装置１の各々に一端が接続された複数本の分岐処理水排出部、８５は複数本の分岐処理水排出部８４が収束した処理水排出部、８６は処理水排出部８５に配設された濾過装置等の固液分離装置である。
【００４１】
実施の形態４における排水処理装置が実施の形態１と異なる点は、排水供給路８１が分岐して複数の排水処理装置１が並列して配設されている点である。
【００４２】
以上のように、実施の形態４における排水処理装置は構成されているので、実施の形態１に記載の作用に加え、以下のような作用が得られる。
（１）複数の排水処理装置が並列して配設されているので、排水処理を終えて処理水を排出した排水処理装置に順次未処理の排水を供給して排水処理を行うことができ、排水処理能力を著しく高めることができる。
【００４３】
【実施例】
以下、本発明を実施例により具体的に説明する。なお、本発明はこれらの実施例に限定されるものではない。
（実施例１）
実施の形態１で説明した排水処理装置を用いて排水処理効果を確認した。排水としては、山口県田万川町江崎集落排水浄化センターの沈殿槽の下部から汲み上げた排水を用いた。山口県田万川町江崎集落排水浄化センターは、各家庭から集められた排水中の大きな夾雑物をスクリーンを用いて除去した後、流量調整槽、接触曝気槽、沈殿槽を経て汚泥と放流水とに分離して排水の処理を行っている。沈殿槽は、接触曝気槽に充填された接触材より剥離した汚泥を沈殿分離させるもので、沈殿槽の下部から汲み上げた排水には多くの汚泥が含まれている。
この排水２００Ｌを容量が２５０Ｌの反応槽内に貯留した後、反応槽オゾンガス供給部、酸素ガス発生部、反応槽第１ポンプを駆動し、排水内にオゾンを含有する微細気泡を供給した。このときのオゾン発生量は９．９８ｇ／ｈ、オゾンガス濃度は２０．８ｇ／Ｎｍ^３であった。また、排ガス中に含まれるオゾンガス濃度は０ｇ／Ｎｍ^３であった。さらに、反応槽第２ポンプを駆動し消泡ノズルから排水を噴射させて泡に付着して浮上分離した汚濁物質を排水内に繰り返し懸濁させた。排水内にオゾンを含有する微細気泡の供給を開始してからの経過時間（処理時間）毎（０，２０，５０，１２０分毎）に反応槽内から処理水を採取し、浮遊物質（ＳＳ）、ＢＯＤ、ＣＯＤ、全窒素（以下、Ｔ−Ｎという）、孔径１μｍのガラス繊維濾紙（ＧＦＰ）を用いて濾過した濾液のＢＯＤ（以下、ＢＯＤ_Ｓという）、濾液のＣＯＤ（以下、ＣＯＤ_Ｓという）、アンモニア性窒素（ＮＨ_４ ^＋−Ｎ）、硝酸性窒素（ＮＯ_３ ⁻−Ｎ）、亜硝酸性窒素（ＮＯ_２ ⁻−Ｎ）を測定した。なお、ＢＯＤ、ＣＯＤ（過マンガン酸カリウム酸化法による）、Ｔ−Ｎ、ＮＨ_４ ^＋−Ｎ、ＮＯ_３ ⁻−Ｎ、ＮＯ_２ ⁻−Ｎの測定はＪＩＳ　Ｋ　０１０２に従って行った。また、ＢＯＤ_Ｓ、ＣＯＤ_Ｓの測定は、試料をの濾過操作以外はＪＩＳ　Ｋ　０１０２に従って行った。ＳＳの測定は昭和４６年環境庁告示５９号に従って行った。
なお、１２０分間の排水処理におけるオゾン注入率は９９．８ｍｇ／Ｌであった。また、排水の温度は２０℃であった。
【００４４】
図５は処理時間と処理水中のＳＳ，ＢＯＤ，ＣＯＤの関係を示した図であり、図６は処理時間と処理水中のＴ−Ｎ，ＢＯＤ_Ｓ，ＣＯＤ_Ｓ，ＮＨ_４ ^＋−Ｎの関係を示した図である。表１は処理時間に対する処理水中のＮＯ_３ ⁻−Ｎ、ＮＯ_２ ⁻−Ｎの量を示した表である。
【表１】

図５乃至図６から、処理時間１２０分で処理水中のＳＳ，ＢＯＤ，ＣＯＤ，Ｔ−Ｎ，ＢＯＤ_Ｓ，ＣＯＤ_Ｓ，ＮＨ_４ ^＋−Ｎを著しく小さくすることができることが確認された。なお、処理時間１２０分後の各測定値は、ＳＳ：８．０ｍｇ／Ｌ，ＢＯＤ：１０．４ｍｇ／Ｌ，ＣＯＤ：１０．６ｍｇ／Ｌ，Ｔ−Ｎ：１４．８ｍｇ／Ｌ，ＢＯＤ_Ｓ：１０．２ｍｇ／Ｌ，ＣＯＤ_Ｓ：８．５ｍｇ／Ｌ，ＮＨ_４ ^＋−Ｎ：０．３４ｍｇ／Ｌであった。
なお、図６において、ＢＯＤ_Ｓ，ＣＯＤ_Ｓの値が処理時間２０〜５０分にかけて一時的に増加しているのは、オゾンの酸化作用によって、汚濁物質が濾紙を通過できる溶解性物質に変化し、その後分解されたことを示していると推察している。また、表１において、処理時間１２０分後にＮＯ_３ ⁻−Ｎ、ＮＯ_２ ⁻−Ｎの量が増加しているのは、オゾンの酸化作用によってＮＨ_４ ^＋−Ｎの分解が進んだことを示していると推察している。
下水道法施行令が求める排水基準では２次処理（具体的には活性汚泥法や散水濾過法等を中心とした処理）により、ＢＯＤが２０ｍｇ／Ｌ以下、ＳＳが７０ｍｇ／Ｌ以下とされているので、本実施例によれば、強い酸化作用を有するオゾンの微細気泡による浮上分離と汚濁物質の分解により、排水基準を大幅に下回る清浄な処理水が得られることが明らかになった。
【００４５】
（実施例２）
実施の形態２で説明した排水処理装置を用いて排水処理効果を確認した。排水としては、山口県田万川町江崎集落排水浄化センターの沈殿槽の下部から汲み上げた排水を用いた。
この排水２００Ｌを容量２５０Ｌの反応槽内に貯留した後、冷却用ジャケットを用いて反応槽内の排水の水温を２５℃に維持した後、反応槽オゾンガス供給部、酸素ガス発生部、反応槽第１ポンプを駆動し、排水内にオゾンを含有する微細気泡を供給した。このときのオゾン発生量は６１．６ｇ／ｈ、オゾンガス濃度は６８．５ｇ／Ｎｍ^３であった。また、排ガス中に含まれるオゾンガス濃度は０ｇ／Ｎｍ^３であった。さらに、反応槽第２ポンプを駆動し消泡ノズルから排水を噴射させて泡に付着して浮上分離した汚濁物質を排水内に繰り返し懸濁させた。排水内にオゾンを含有する微細気泡の供給を３０分間行った後（処理時間３０分）、反応槽内から処理水と排泡及び排泥スラリー（以下、排泡・排泥という）とを採取し、ｐＨ、溶存酸素量（ＤＯ）、ＢＯＤ、ＣＯＤ、ＢＯＤ_Ｓ、ＣＯＤ_Ｓ、浮遊物質（ＳＳ）、揮発性浮遊物質（ＶＳＳ）、蒸発残留物（１０５〜１１０℃で２時間乾燥後の残留物）、強熱減量（蒸発残留物を８００℃程度の高温で強熱した減量分）、全窒素（Ｔ−Ｎ）、アンモニア性窒素（ＮＨ_４ ^＋−Ｎ）、硝酸性窒素（ＮＯ_３ ⁻−Ｎ）、亜硝酸性窒素（ＮＯ_２ ⁻−Ｎ）、全リン（Ｔ−Ｐ）、Ｃｕ、一般細菌数、大腸菌数を測定した。なお、ＢＯＤ、ＣＯＤ（過マンガン酸カリウム酸化法による）、Ｔ−Ｎ、ＮＨ_４ ^＋−Ｎ、ＮＯ_３ ⁻−Ｎ、ＮＯ_２ ⁻−Ｎの測定はＪＩＳ　Ｋ０１０２に従って行った。また、ＢＯＤ_Ｓ、ＣＯＤ_Ｓの測定は、試料の濾過操作以外はＪＩＳ　Ｋ　０１０２に従って行った。ＳＳの測定は昭和４６年環境庁告示５９号に従って行った。その他の分析操作は下水試験法に準拠した。なお、３０分間の排水処理におけるオゾン注入率は３０８ｍｇ／Ｌであった。
反応槽内及び処理槽内の排水や汚泥スラリー等を全て排出した後、同様に山口県田万川町江崎集落排水浄化センターの沈殿槽から汲み上げた排水２００Ｌを同じ反応槽内に貯留した後、冷却用ジャケットを用いて反応槽内の排水の水温を２０℃に維持した。次いで、同様の処理を３０分間行った後に処理水を採取し、同様の分析を行った。これらの分析値を未処理の排水の分析値と比較した。その結果を表２に示す。
【表２】

【００４６】
表２から、以下のことが明らかになった。
（１）排水の水温を２０℃に維持することにより、２５℃に維持した場合と比較して、処理水のｐＨが低くなり溶存酸素量が高くなることが確認された。これは、水温が低い方がオゾンの溶解度が高まり酸化分解が活発に行われることを示している。また、排水（原水）の溶存酸素量と比較すると１０倍程度の高い値を示すことが明らかになった。これは処理水や排泡・排泥が好気性の水質や土質に変化していることを示している。
（２）排水の水温を２０℃に維持することにより、２５℃に維持した場合と比較して、ＢＯＤ_Ｓ、ＣＯＤ_Ｓが高くなることが確認された。これは、オゾンによる酸化分解が活発化するため、排水中の有機物が分解されて低分子化し溶解性の有機物が増加したことを示している。
（３）排水と比較して処理水中のＣｕの量が著しく減少していることが確認された。これは、排水中のＣｕイオンが酸化されて析出し、処理水から分離されて排泡や排泥中に含まれたことを示している。この結果、処理水を脱水処理して採取される固形分は、土壌汚染物質であるＣｕの含有量が著しく少ないことが明らかになった。また、排泡・排泥には窒素、リン等の栄養塩類が多量に含まれており植物の栽培に適していることが明らかになった。
（４）処理水中の一般細菌数及び大腸菌数をほぼ０にできることが確認された（下水道法施行令が求める排水基準では２次処理により、大腸菌群数は３０００個／ｃｍ^３以下）。これにより、処理水、処理水や排泥・排泡を脱水処理して採取される固形分は、無菌で非常に衛生的であることが明らかになった。これらの結果から、従来は大部分が埋立処理されていた余剰汚泥等の固形廃棄物を、土壌改良材としてリサイクルすることが可能であり、排水を資源として有効に活用できることを示している。
（５）排水（原水）に比べて処理水の粘度が低下するとともに、排泡・排泥の蒸発残留物の量が、排水の蒸発残留物の量の約５倍に増加することが確認された。これは、排泡・排泥が排水に比べ濃度が約５倍に増加し著しく濃縮されていることを示している。この結果、本実施例によれば、汚泥の濃縮性を向上させ余剰汚泥等の固形廃棄物の発生量を大幅に減少させることができることが明らかになった。
【００４７】
【発明の効果】
以上のように、本発明の排水処理装置及びこれを用いた土壌改良材の製造方法によれば、以下のような有利な効果が得られる。
請求項１に記載の発明によれば、
（１）排水が貯留される反応槽と、反応槽と連通する反応層第１連通部と、反応層第１連通部に配設された反応槽第１ポンプと、オゾンガスを系内に供給する反応槽オゾンガス供給部と、を備えているので、反応槽，反応槽第１連通部内の排水にオゾンガスを微細気泡にして拡散して供給することにより、オゾンの酸化力によって排水中の有機物の酸化分解、金属イオンの酸化・析出、排水の脱臭，脱色，殺菌等が行われ排水基準を大幅に下回る清浄な処理水を得ることができる排水処理装置を提供することができる。このため産業用廃水等の処理だけでなく、上水、工業用水等の水処理全般に広く用いることにできる汎用性に優れた排水処理装置を提供することができる。
（２）オゾンガスを反応槽第１ポンプの上流側に供給するので、供給されたオゾンガスを反応槽第１ポンプのインペラにより排水中に微細気泡として拡散させることができる。また、反応層第１連通部を備え排水を循環させるので、排水が反応槽内で撹拌されて排水が微細気泡のオゾンガスと同伴し繰り返しオゾンガスと接触し排水処理効率を高めることができる。
（３）オゾンの酸化分解によって、汚泥中のタンパク質等の有機性物質等が酸化分解されて可溶化されるとともに、粘性を発現するタンパク質等の分解により汚泥の粘性が低下するので、汚泥の濃縮性を向上させ汚泥の発生量を大幅に減少させることができる排水処理装置を提供することができる。
（４）オゾンガスを用いて酸化分解するので、流入水質や水量の変動、気候等の環境条件の変動に対しても、安定して水質の良好な処理水を得ることができる安定性に優れた排水処理装置を提供することができる。
（５）オゾンを用いた酸化分解によって酸素が生成されるので、周辺環境に二次的な環境汚染を引き起こさず、またオゾンの強力な酸化力によって殺菌され衛生的な処理水や汚泥の得られる排水処理装置を提供することができる。さらに、処理水はオゾンの酸化力によって好気性の水質に変化しているので、河川等へ放流することはもちろん、生物処理の前処理として生物分解槽に注入することもでき応用性の高い排水処理装置を提供することができる。
（６）装置の構成が簡単なので、建設費や運転管理費を少なくすることができ設備負荷を小さくすることができ、大都市近郊や工場等の大規模な排水処理だけでなく、中小都市や農山村地域において汚濁水発生源若しくは小集落ごとに排水処理を行う小規模排水処理装置として用いることができる排水処理装置を提供することができる。また、設置に多くの敷地面積を要さないので、車両等に搭載して汚濁水発生源や小集落等を巡回する移動式の排水処理装置としても用いることができ汎用性に優れた排水処理装置を提供することができる。
【００４８】
請求項２に記載の発明によれば、請求項１の効果に加え、
（１）反応槽第１連通部に微細気泡発生手段が配設されているので、オゾンガスを微細気泡に含有させて排水中に供給することができ、オゾンの排水中の滞在時間を長くすることができるとともに排水に対するオゾンの溶解度を増加させて酸化分解反応を活発化させることができ、さらに排水中の汚濁物質が微細気泡に付着して浮上分離され排水処理効率に著しく優れた排水処理装置を提供することができる。
【００４９】
請求項３に記載の発明によれば、請求項１又は２の効果に加え、
（１）反応槽第２連通部と、反応槽第２連通部に配設された反応槽第２ポンプと、反応槽第２連通部に接続された消泡ノズルと、を備えているので、注入された微細気泡に付着して浮上分離した汚濁物質に消泡ノズルから排水を吹き付けて消泡させ、汚濁物質を再び排水中に懸濁させることができる。また、排水の流滴等を反応槽上部のオゾンガス層に繰り返し接触させることができる。これによって、汚濁物質がオゾンガスに繰り返し接触し汚濁物質の分解が促進される排水処理効率の高い排水処理装置を提供することができる。
【００５０】
請求項４に記載の発明によれば、請求項１乃至３の内いずれか１の効果に加え、
（１）反応槽が冷却装置や断熱部材を備えているので、気温の高い夏季においても排水の水温を低く保つことができ、オゾンの溶解度を高め酸化分解反応等の反応を向上させ排水処理効率の高い排水処理装置を提供することができる。
【００５１】
請求項５に記載の発明によれば、請求項１乃至４の内いずれか１の効果に加え、
（１）反応槽内の排水の水温が低温に維持されているので、オゾンの溶解度が低下するのを防止し安定した排水処理効率を得ることができる安定性に優れた排水処理装置を提供することができる。
【００５２】
請求項６に記載の発明によれば、請求項１乃至５の内いずれか１の効果に加え、
（１）汚泥スラリー排出部や排泡部を備えているので、排水のオゾン処理を行った後に反応槽の底部に沈降した汚泥や微細気泡に付着した汚泥を処理水とは別に反応槽の外部に排出することができ、排水中の汚泥を分離濃縮することができ濃縮性が高く固形廃棄物の発生量が少ない排水処理装置を提供することができる。
【００５３】
請求項７に記載の発明によれば、請求項６の効果に加え、
（１）汚泥スラリー排出部や排泡部に接続された処理槽を備えているので、反応槽から排出された汚泥を処理槽でオゾンを用いてさらに酸化分解させることができ、汚泥等の固形廃棄物の減容を図ることができる排水処理装置を提供することができる。
（２）反応槽の底部に沈降した汚泥や微細気泡に付着して浮上分離した汚泥を処理槽に導いて汚泥を濃縮させ減容させることができるので、反応槽と処理槽で並行して排水処理を進めることができ作業性に優れた排水処理装置を提供することができる。
【００５４】
本発明の請求項８に記載の発明によれば、請求項１乃至７の内いずれか１の効果に加え、
（１）排水流入口に接続された溶解槽と、排水流入路に配設され排水を圧送するとともに溶解槽内を加圧する圧送ポンプと、排水流入路に接続された溶解槽オゾンガス供給部と、を備えているので、溶解槽内で排水が加圧されオゾンを過飽和状態で溶解させることができオゾンによる酸化分解効率を高めることができる排水処理装置を提供することができる。
（２）溶解槽内で加圧されてオゾンが過飽和状態で溶解した排水が大気圧下の反応槽に放出されるので、溶解したオゾンが微細気泡として多量に出現し汚濁物質の浮上分離及び酸化分解反応が直ちに行われ排水処理時間を著しく短縮することができ作業性に優れた排水処理装置を提供することができる。
【００５５】
本発明の請求項９に記載の発明によれば、
（１）オゾン処理された処理水や汚泥スラリーを脱水処理して固形分を採取するので、大腸菌等の細菌類がなく無菌で衛生的な土壌改良材を製造できる土壌改良材の製造方法を提供することができる。また、処理水等の溶存酸素量が著しく高いので、固形分の好気性が高く土壌菌等が繁殖し易く作物の栽培に適した土壌改良材を製造できる土壌改良材の製造方法を提供することができる。また、処理水を脱水処理して採取された固形分からは、銅，カドミウム，亜鉛等の土壌汚染物質の含有量の少ない土壌改良材を製造できる土壌改良材の製造方法を提供することができる。
（２）処理水を固液分離して得られた固形分は、有機物が分解され窒素やリン等を含有するので作物の栽培に適した土壌改良材の製造方法を提供することができる。
（３）オゾンの酸化力によって好気性の土質に変化しているので、もみがら，わら等の有機物を加えた後にコンポスト化することも容易であり汎用性に優れた土壌改良材が製造できる土壌改良材の製造方法を提供することができる。
【図面の簡単な説明】
【図１】実施の形態１における排水処理装置の模式図
【図２】実施の形態２における排水処理装置の模式図
【図３】実施の形態３における排水処理装置の模式図
【図４】実施の形態４における排水処理装置の模式図
【図５】処理時間と処理水中のＳＳ，ＢＯＤ，ＣＯＤの関係を示した図
【図６】処理時間と処理水中のＴ−Ｎ，ＢＯＤ_Ｓ，ＣＯＤ_Ｓ，ＮＨ_４ ^＋−Ｎの関係を示した図
【符号の説明】
１　排水処理装置
２　排水貯留槽
３　排水ポンプ
４　排水供給路
５　排水供給弁
６　反応槽
７　排水流入口
８　反応槽第１連通部
９　排水吸引口
１０　排水注入口
１１　反応槽第１ポンプ
１２　反応槽オゾンガス供給部
１３　酸素ガス発生部
１４　反応槽第２連通部
１５　反応槽第２ポンプ
１６　消泡ノズル
１７　汚泥スラリー排出部
１８　排泥弁
１９　排泥ポンプ
２０　固液分離装置
２１　排泡部
２２　排泡ポンプ
２３　処理水排出部
２４　処理水排出弁
２５　処理水排出ポンプ
２６　固液分離装置
２７　排ガス管
２８　オゾン濃度検出装置
２９　排オゾン処理装置
３０　排水処理装置
３１　冷却用ジャケット
３２　処理槽
３３　処理槽第１連通部
３３ａ　微細気泡発生手段
３４　汚泥吸引口
３５　汚泥注入口
３６　処理槽第１ポンプ
３７　処理槽オゾンガス供給部
３８　酸素ガス発生部
３９　処理槽第２連通部
４０　処理槽第２ポンプ
４１　消泡ノズル
４２　第１汚泥排出部
４３　第１汚泥排出弁
４４　第２汚泥排出部
４５　第２汚泥排出弁
４６　汚泥排出部
４７　汚泥排出ポンプ
４８　固液分離装置
４９　排ガス管
５０　オゾン濃度検出装置
５１　排オゾン処理装置
６０　排水処理装置
６１　排水流入路
６２　排水流入弁
６３　圧送ポンプ
６４　溶解槽オゾンガス供給部
６５　酸素ガス発生部
６６　溶解槽
６７　連通部
６８　連通弁
６９　排水輸送ポンプ
７０　冷却用ジャケット
７１　断熱部材
７２　冷却ガス発生部
７３　冷却ガス噴射ノズル
８０　排水処理装置
８１　排水供給路
８２　分岐供給路
８３　分岐供給弁
８４　分岐処理水排出部
８５　処理水排出部
８６　固液分離装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wastewater treatment apparatus for treating wastewater containing pollutants such as industrial wastewater, sewage and human waste, and a method for producing a soil conditioner using the same.
[0002]
[Prior art]
Conventionally, wastewater such as industrial wastewater, sewage, polluted water, and human waste, such as solid-liquid separation operations such as coagulation, precipitation, and filtration, and biological treatment such as activated sludge method using chemical reactions. Etc. are done. The treated water treated by these is discharged into rivers and the like, and solid waste such as excess sludge separated from the treated water is incinerated for volume reduction as needed and disposed of by landfill.
Therefore, at least for wastewater treatment, remove pollutants such as organic substances, harmful substances, suspended solids, and nutrients in the treated water to obtain treated water that satisfies the wastewater standards, and the amount of solid waste such as excess sludge generated. Is required to be low.
In recent years, an apparatus using ozone having strong oxidizing power has been developed as a wastewater treatment apparatus for satisfying such a demand.
[0003]
As a conventional technique, for example, (Patent Document 1) describes “a method for reforming organic sludge in which the pH of sludge is adjusted to 3 to 6 and then contacted with a gas containing ozone in a pressurized atmosphere”. Yes.
[0004]
(Patent Document 2) includes "a first treatment step for mixing and treating sludge and ozone gas, a second treatment step for retaining and treating sludge and ozone gas mixed and contacted in the first treatment step for a certain period of time; And a third treatment step in which the sludge treated with ozone in the second treatment step is subjected to a solid-liquid separation treatment into a separated liquid and a concentrated sludge ”.
[0005]
(Patent Document 3) states that “a treated water supply system for supplying treated water with a pressure pump, ozone generating means for generating ozone, and a pressure pump for the treated water supply system for the generated ozone. "High-speed ozone reaction system comprising ozone injection means for injecting upstream of ozone and ozone reaction means for subjecting water to which ozone has been injected to an ozone reaction treatment in an ozone reaction tank while maintaining a pressurized state" Has been.
[0006]
[Patent Document 1]
JP 59-4500
[Patent Document 2]
JP 2000-246293 A
[Patent Document 3]
JP-A-10-230285
[0007]
[Problems to be solved by the invention]
However, the above conventional techniques have the following problems.
(1) The technique described in (Patent Document 1) has a problem that a pressurized container is required and the apparatus becomes large and complicated.
(2) Since sludge water is showered and brought into contact with the ozone-containing gas filled in the container, there is a problem that the contact efficiency between ozone and sludge is low and the treatment efficiency is low.
(3) Since ozone is supplied into sludge water using an air diffuser, there is a problem that the bubble diameter of ozone gas is as large as 0.2 to 0.8 mm, and the amount of ozone dissolved in sludge water is small and the treatment efficiency cannot be increased. Had. Further, there is a problem that the air diffuser is easily clogged and lacks in maintainability.
(4) The technique described in (Patent Document 2) has a problem that the time required for the sludge treatment becomes long because the sludge and ozone gas are retained for a certain period of time.
(5) Since an ozone retention tank and a gravity concentration tank are required, the entire apparatus has a problem of increasing in size.
(6) Since the technique described in (Patent Document 3) requires an ozone reaction tank in which ozone and water to be treated are reacted in a pressurized state, there is a problem that the apparatus becomes large and complicated. It was.
[0008]
The present invention solves the above-described conventional problems, and can be used as a small-scale wastewater treatment apparatus with a small equipment load because the structure is simple and can be miniaturized, and is excellent in versatility, and oxidative decomposition of organic matter in wastewater, Oxidation / precipitation of metal ions, drainage deodorization, decolorization, sterilization, etc. can be performed very efficiently, and clean treated water significantly lower than the drainage standard can be obtained, and the concentration of sludge is improved. An object of the present invention is to provide a wastewater treatment apparatus capable of greatly reducing the amount of solid waste generated.
In addition, the present invention has a low content of soil contaminants such as copper, is free of bacteria such as Escherichia coli, is sterile and hygienic, suitable for cultivation of crops, is extremely aerobic, and is capable of breeding soil bacteria and the like. An object of the present invention is to provide a method for producing a soil improvement material which is easy and can be easily composted and has excellent versatility.
[0009]
[Means for Solving the Problems]
In order to solve the above conventional problems, a wastewater treatment apparatus of the present invention and a method for producing a soil improvement material using the same have the following configurations.
[0010]
The waste water treatment apparatus according to claim 1 of the present invention is in communication with the reaction tank having a drain inlet and a drainage suction port at one end and a drain inlet at the other end. A reaction tank first communication section; a reaction tank first pump disposed in the reaction tank first communication section for circulating waste water; and the reaction tank first communication section upstream of the reaction tank first pump. And a reaction tank ozone gas supply unit for supplying ozone gas into the system.
With this configuration, the following effects can be obtained.
(1) A reaction tank in which wastewater is stored, a reaction layer first communication part communicating with the reaction tank, a reaction tank first pump disposed in the reaction layer first communication part, and ozone gas are supplied into the system. A reaction tank ozone gas supply unit, so that ozone gas is diffused and supplied to the waste water in the reaction tank and the first communication part of the reaction tank to oxidize organic matter in the waste water by the oxidizing power of ozone. Decomposition, oxidation / precipitation of metal ions, deodorization, decolorization, sterilization, etc. of wastewater are performed, and clean treated water that is significantly lower than the wastewater standard can be obtained.
(2) Since ozone gas is supplied to the upstream side of the reaction tank first pump, the supplied ozone gas can be diffused as fine bubbles in the waste water by the impeller of the reaction tank first pump. Moreover, since the waste water is circulated with the reaction layer first communicating portion, the waste water is agitated in the reaction tank, and the waste water is accompanied by the fine bubble ozone gas and repeatedly comes into contact with the ozone gas, thereby improving the waste water treatment efficiency.
(3) Oxidative decomposition of organic matter such as protein in sludge is oxidatively decomposed and solubilized by the oxidative decomposition of ozone, and the viscosity of sludge is reduced by the decomposition of protein that develops viscosity. And the amount of sludge generated can be greatly reduced.
(4) Since oxidative decomposition is performed using ozone gas, treated water having stable and good water quality can be obtained even with respect to changes in the quality of inflow water, the amount of water, and changes in environmental conditions such as climate.
(5) Since oxygen is generated by oxidative decomposition using ozone, secondary environmental pollution is not caused in the surrounding environment, and treated water and sludge are sanitized by the strong oxidizing power of ozone. Furthermore, since the treated water has been changed to an aerobic water quality due to the oxidizing power of ozone, it can be discharged into rivers and the like, and can also be injected into a biodegradation tank as a pretreatment for biological treatment.
(6) Since the structure of the equipment is simple, construction costs and operation management costs can be reduced, and the equipment load can be reduced. In addition to large-scale wastewater treatment in suburban areas and factories, It can be used as a small-scale wastewater treatment device that performs wastewater treatment for each source of polluted water or small villages in rural areas. In addition, since a large site area is not required for installation, it can be used as a mobile wastewater treatment apparatus that is mounted on a vehicle or the like and circulates a polluted water generation source or a small village, and is excellent in versatility.
[0011]
Here, as waste water, industrial waste water, sewage, polluted water containing organic or inorganic floating substances, human waste, and the like are used.
[0012]
As the reaction tank ozone gas supply unit, one that generates and supplies ozone gas by chemical reaction, photochemical reaction, electrolytic reaction, discharge reaction (silent discharge) or the like is used. The reaction tank ozone gas supply part can use oxygen in the air as a raw material, but the oxygen gas generation part is connected to the reaction tank ozone gas supply part to increase the oxygen concentration in the air and supply high concentration oxygen to the reaction tank ozone gas By supplying to the unit, the ozone gas concentration in the air can be increased. Thereby, high-concentration ozone together with air and oxygen or high-concentration ozone together with oxygen can be supplied to the reaction tank and the reaction tank first communication part to increase the amount of ozone generated and increase the oxidative decomposition efficiency of the waste water.
[0013]
As the ozone injection rate (mg / L) representing the ozone amount (mg) with respect to the volume (L) of the waste water in the reaction tank, 30 to 1000 mg / L is used, although it depends on the pollution degree of the waste water. As the ozone injection rate becomes lower than 30 mg / L, the amount of ozone with respect to the capacity of the waste water tends to decrease and the processing efficiency tends to decrease. As the ozone injection rate becomes higher than 1000 mg / L, a large amount of power is required to drive the reaction tank ozone gas supply unit. Therefore, energy efficiency is lowered and the life of the reaction vessel ozone gas supply unit tends to be shortened.
The ozone injection rate (mg / L) is expressed by (Equation 1).
[Expression 1]

[0014]
Irradiation, addition or contact with metal oxidation catalysts such as ultraviolet rays, hydrogen peroxide, titanium oxide, etc. in addition to ozone accelerates the decomposition of organic substances, etc. and promotes environmental hormones, dioxins, organochlorine compounds, etc. Can promote the degradation of environmental pollutants.
[0015]
A second aspect of the present invention is the waste water treatment apparatus according to the first aspect of the present invention, and has a configuration in which fine bubble generating means is disposed in the reaction tank first communicating portion.
With this configuration, in addition to the operation obtained in the first aspect, the following operation can be obtained.
(1) Since the fine bubble generating means is disposed in the first communicating portion of the reaction tank, ozone gas can be contained in the fine bubbles and supplied into the waste water, and the residence time of the ozone in the waste water can be increased. In addition, the solubility of ozone in the waste water can be increased to activate the oxidative decomposition reaction, and the pollutants in the waste water can be attached to the fine bubbles and floated to increase the waste water treatment efficiency.
[0016]
Here, as the fine bubble generating means, one provided with an ejector disposed in the reaction tank first communicating portion on the downstream side of the reaction tank first pump can be used. Thereby, ozone gas is attracted | sucked from an ejector with the negative pressure by the jet flow of the waste_water | drain injected from a waste_water | drain injection port, The fine bubble containing ozone can be generated by the shearing effect | action which acts on a gas flow. In addition, a reaction tank ozone gas supply unit is provided on the upstream side of a vortex turbine pump (manufactured by Nikuni Co., Ltd.) and the like disposed in the first communication section of the reaction tank. Can be pumped. In this case, the first reaction tank pump and the fine bubble generating means can be used together. Thereby, high-concentration ozone gas can be dissolved in the waste water as fine bubbles, and the apparatus configuration can be simplified. Moreover, a reaction tank ozone gas supply part can be provided in the upstream of a reaction tank 1st pump, and a fine bubble generator (made by Bubble Tank) can be arrange | positioned in the reaction tank 1st communication part in the downstream of this pump. Thereby, the bubble in the waste_water | drain containing ozone can be refined | miniaturized remarkably. The fine bubble generating means is not limited to these, and any means can be used as long as it can make the bubbles in the waste water fine.
[0017]
The average bubble diameter of fine bubbles is 0.01 to 200 μm, preferably 0.5 to 50 μm. As the average bubble diameter becomes smaller than 0.5 μm, the means for generating fine bubbles tends to become complicated, and as it becomes larger than 50 μm, the fine bubbles supplied in the drainage immediately rise up, depending on the viscosity of the drainage. However, it is not preferable because the retention time in the waste water is short and the processing efficiency tends to decrease. In particular, when the distance is smaller than 0.01 μm or larger than 200 μm, these tendencies become remarkable, so that neither is preferable. The measurement of the bubble diameter can be calculated by placing a glass plate on the surface of the water, photographing the bubbles in the water with a digital camera, and performing image processing.
[0018]
Invention of Claim 3 of this invention is the waste water treatment apparatus of Claim 1 or 2, Comprising: One end was connected with the predetermined part of the said reaction tank, and the other end was connected with the upper part of the said reaction tank. A reaction tank second communication part, a reaction tank second pump that is disposed in the reaction tank second communication part and circulates waste water, and a defoaming nozzle connected to the other end of the reaction tank second communication part. It has the composition provided.
With this configuration, in addition to the operation obtained in the first or second aspect, the following operation can be obtained.
(1) Since it comprises a reaction tank second communication part, a reaction tank second pump disposed in the reaction tank second communication part, and a defoaming nozzle connected to the reaction tank second communication part, The pollutant that adheres to the injected fine bubbles and floats and separates can be defoamed by spraying the drainage from the defoaming nozzle, and the pollutant can be suspended again in the drainage. Moreover, it is possible to repeatedly contact the wastewater droplets or the like with the ozone gas layer above the reaction tank. As a result, the pollutant is repeatedly brought into contact with ozone gas, the decomposition of the pollutant is promoted, and the wastewater treatment efficiency can be increased.
[0019]
The invention according to claim 4 of the present invention is the waste water treatment apparatus according to any one of claims 1 to 3, wherein the cooling apparatus and / or the reaction tank disposed in the reaction tank is covered. It has the structure provided with the provided heat insulation member.
According to this configuration, in addition to the action obtained in any one of claims 1 to 3, the following action is obtained.
(1) Since the reaction tank is equipped with a cooling device and a heat insulating member, the temperature of the wastewater can be kept low even in summer when the temperature is high, and the wastewater treatment efficiency is improved by increasing the solubility of ozone and improving the reaction such as oxidative decomposition reaction. Can be improved. This is because the solubility of ozone in water increases as the water temperature decreases.
[0020]
Here, as the cooling device, (1) a cooling jacket is provided outside the reaction tank and cooling water or cold air is flown inside or ice is stored to cool the inside, (2) outside the reaction tank. Cooling by disposing fins for heat dissipation and air cooling, (3) Cooling water discharge by disposing a cooling gas injection nozzle inside the reaction tank and injecting cooled gas into the drainage, etc. Any one or more of these can be used.
[0021]
The invention according to claim 5 of the present invention is the waste water treatment apparatus according to any one of claims 1 to 4, wherein the temperature of the waste water in the reaction tank is 28 ° C or lower, preferably 20 ° C or lower. It has the structure maintained by this.
With this configuration, in addition to the action obtained in any one of claims 1 to 4, the following action is obtained.
(1) Since the water temperature of the waste water in the reaction tank is maintained at a low temperature, it is possible to prevent a decrease in the solubility of ozone and to obtain a stable waste water treatment efficiency.
[0022]
Here, as the water temperature of the waste water in the reaction tank becomes higher than 20 ° C., the solubility of ozone in the water is lowered, and the oxidative decomposition reaction due to ozone tends to be poor, and the waste water treatment efficiency tends to be lowered. In particular, when the water temperature is higher than 28 ° C., this tendency becomes remarkable, which is not preferable. In addition, since the minimum of the water temperature of waste_water | drain should just be the water temperature which waste_water | drain does not freeze, it should just be maintained at the temperature higher than 0 degreeC. However, a water temperature of 0 ° C. or less may be used as long as the inside of the reaction tank or the like can always flow and does not freeze.
[0023]
The invention according to claim 6 of the present invention is the waste water treatment apparatus according to any one of claims 1 to 5, wherein the sludge slurry is connected to a predetermined portion of the bottom of the reaction tank or its side. It has the structure provided with the foaming part connected to the discharge part and / or the predetermined part above the said reaction tank.
With this configuration, in addition to the action obtained in any one of claims 1 to 5, the following action is obtained.
(1) Since the sludge slurry discharge part and the exhaust bubble part are provided, the sludge that settles on the bottom of the reaction tank after the ozone treatment of the waste water and the sludge adhering to fine bubbles are separated from the treated water outside the reaction tank. The sludge in the waste water can be separated and concentrated.
[0024]
Invention of Claim 7 of this invention is a waste water treatment apparatus of Claim 6, Comprising: The processing tank connected to the said sludge slurry discharge part and / or the said foam removal part, and a sludge suction inlet at one end Has a sludge inlet formed at the other end and communicates with the treatment tank, a treatment tank first communication portion, a treatment tank first pump disposed in the treatment tank first communication portion to circulate sludge, and the treatment tank first And a treatment tank ozone gas supply unit connected to the treatment tank first communication part on the upstream side of one pump.
With this configuration, in addition to the operation obtained in the sixth aspect, the following operation can be obtained.
(1) Since it has a treatment tank connected to the sludge slurry discharge part and the bubble removal part, the sludge discharged from the reaction tank can be further oxidatively decomposed using ozone in the treatment tank. The volume of waste can be reduced.
(2) Since sludge settled at the bottom of the reaction tank and sludge that floats and separates by adhering to fine bubbles can be guided to the treatment tank to concentrate and reduce the volume of sludge, waste water is discharged in parallel in the reaction tank and the treatment tank. Processing can be advanced and workability is excellent.
[0025]
Here, the fine bubble generating means described in claim 2 can be arranged in the first communication portion of the processing tank. Thereby, the same operation as that described in claim 2 is obtained.
[0026]
The invention according to claim 8 of the present invention is the wastewater treatment apparatus according to any one of claims 1 to 7, wherein the dissolution tank is connected to the drainage inlet, and is connected to the dissolution tank. Connected to the drainage inflow passage for allowing the wastewater to flow into the dissolution tank, the pressure feed pump disposed in the drainage inflow passage for pumping the wastewater and pressurizing the inside of the dissolution tank, and the drainage inflow passage upstream of the pressure feed pump And a dissolving tank ozone gas supply unit.
With this configuration, in addition to the action obtained in any one of claims 1 to 7, the following action is obtained.
(1) a dissolution tank connected to a drainage inlet, a pressure feed pump disposed in a drainage inflow path to pressurize wastewater and pressurize the inside of the dissolution tank, a dissolution tank ozone gas supply unit connected to the drainage inflow path, Since the waste water is pressurized in the dissolution tank, ozone can be dissolved in a supersaturated state, and the oxidative decomposition efficiency by ozone can be increased.
(2) Since the wastewater that has been pressurized in the dissolution tank and dissolved in a supersaturated state of ozone is released into the reaction tank under atmospheric pressure, a large amount of dissolved ozone appears as fine bubbles, and the floating separation and oxidation of pollutants The decomposition reaction takes place immediately and the wastewater treatment time can be significantly shortened, resulting in excellent workability.
[0027]
Here, the pressure feed pump preferably pressurizes the dissolution tank at a pressure of 0.2 to 1 MPa. As the pressure becomes smaller than 0.2 MPa, since the pressure becomes smaller, there is a tendency that the increase in the solubility of ozone is small and it is difficult to increase the effect of increasing the oxidative decomposition efficiency. As the pressure becomes higher than 1 MPa, This tends to increase the equipment load due to the increase in size.
Note that the fine bubble generating means described in claim 2 can be disposed in the drain inflow passage. Thereby, the same operation as that described in claim 2 is obtained.
[0028]
The method for producing a soil improvement material according to claim 9 of the present invention supplies ozone gas while circulating the wastewater stored in the reaction tank using the wastewater treatment device according to any one of claims 1 to 8. The ozone treatment step for ozone treatment of the waste water, the discharge step for discharging the treated water and sludge slurry treated in the ozone treatment step from the reaction tank, and the discharged treated water and / or the sludge slurry And a dehydration treatment step of collecting a solid content to be used alone or in combination as a soil improvement material after dehydration.
With this configuration, the following effects can be obtained.
(1) Since the solids are collected by dehydrating the treated water and sludge slurry that have been subjected to ozone treatment, it is possible to produce a sterile and sanitary soil conditioner that is free of bacteria such as Escherichia coli. In addition, since the amount of dissolved oxygen such as treated water is extremely high, it is possible to produce a soil improvement material that is highly aerobic in the solid content and easily proliferates soil fungi and is suitable for crop cultivation. This is because harmful bacteria are killed by the oxidizing action of ozone and the ozone is oxidized with decomposed oxygen. Moreover, the soil improvement material with little content of soil pollutants, such as copper, cadmium, and zinc, can be manufactured from the solid content collected by dehydrating the treated water. Ozone treatment oxidizes and precipitates metal ions of soil pollutants in the wastewater and is separated from the treated water, so it is not included in the treated water, so it is not included in the solids collected by dehydrating the treated water. It is.
(2) The solid content obtained by solid-liquid separation of treated water or sludge slurry is suitable for crop cultivation because organic matter is decomposed and contains nitrogen, phosphorus and the like.
(3) Since it has changed to an aerobic soil due to the oxidizing power of ozone, it can be easily composted after adding organic substances such as rice husk and straw and is excellent in versatility.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 is a schematic diagram of a wastewater treatment apparatus in the first embodiment.
In the figure, 1 is a wastewater treatment apparatus in the first embodiment, 2 is a wastewater storage tank in which wastewater such as industrial wastewater, sewage and human waste is collected and stored, and 3 is a water collection that is immersed in the wastewater storage tank 2. A drainage pump for pumping the drained wastewater, 4 is a drainage supply passage connected at one end to the drainage pump 3, 5 is a drainage supply valve disposed in the drainage supply passage 4, 6 is a reaction tank in which wastewater is stored, 7 Is a drainage inlet formed on the lower side of the reaction tank 6 and connected to the other end of the drainage supply path 4, 8 is a first communication tank communicating with the upper and lower sides of the reaction tank 6, and 9 is a reaction tank first. A drainage suction port 10 is formed at one end of the communication portion 8 and sucks the wastewater supplied to the reaction tank 6. A wastewater suction port 10 is formed at the other end of the reaction tank first communication portion 8 and sucked from the drainage suction port 9. The drainage inlet 11 for injecting into the reactor 6 is disposed in the first communication part 8 of the reaction tank, and drainage is discharged from the drainage suction port 9. A first pump reactor to circulate to the inlet 10. In the present embodiment, a vortex turbine pump (manufactured by Nikuni Co., Ltd.) is used as the reaction tank first pump 11, and this is also used as a fine bubble generating means.
A reaction tank 12 is connected to the reaction tank first communication section 8 on the upstream side of the reaction tank first pump 11 to convert oxygen into ozone by a silent discharge type ozonizer or the like and supply air or oxygen together with ozone or oxygen into the system. An ozone gas supply unit 13 is an oxygen gas generation unit that produces high-concentration oxygen as a raw material of ozone from air using zeolite or the like and supplies it to the reaction tank ozone gas supply unit 12, and one end communicates with the lower part of the reaction tank 6. The reaction tank second communication part 15 is connected to the reaction tank 6 at the other end, 15 is a reaction tank second pump which is disposed in the reaction tank second communication part 14 and circulates waste water, and 16 is the reaction tank second communication. The defoaming nozzle connected to the other end of the part 14 and disposed at the top of the reaction tank 6, 17 is a sludge slurry discharge part connected to the bottom of the reaction tank 6, and 18 is disposed in the sludge slurry discharge part 17. Mud valve, 1 Is a sludge pump disposed in the sludge slurry discharge section 17, 20 is a solid-liquid separator such as a filtration device disposed in the sludge slurry discharge section 17, and 21 is connected to a predetermined section above the reaction tank 6. Defoaming section, 22 is a defoaming pump disposed in the defoaming section 21, 23 is a treated water discharge section connected to a predetermined section of the reaction tank 6, and 24 is treated water disposed in the treated water discharge section 23. A discharge valve, 25 is a treated water discharge pump disposed in the treated water discharge section 24, 26 is a solid-liquid separator such as a filtration device disposed in the treated water discharge section 23, and 27 is connected to the upper part of the reaction tank 6. The exhaust gas pipe 28 is disposed in the exhaust gas pipe 27 and an ozone concentration detecting device for measuring the ozone concentration in the exhaust gas. 29 is disposed in the exhaust gas pipe 27 and contains activated carbon that adsorbs and decomposes ozone in the exhaust gas. This is an exhaust ozone treatment device.
[0030]
About the waste water treatment equipment in Embodiment 1 comprised as mentioned above, the usage method is demonstrated below.
In the ozone treatment process, first, the drainage supply valve 5 disposed in the drainage supply path 4 is opened, and then the drainage pump 3 is driven to supply the drainage collected in the drainage storage tank 2 to the reaction tank 6. . After the water level of the drainage reaches a position higher than the drainage suction port 9, the drainage pump 3 is stopped and the drainage supply valve 5 is closed.
Next, the reaction tank first pump 11 is driven to circulate the waste water, and the oxygen gas generation unit 13 and the reaction tank ozone gas supply unit 12 are driven so that ozone gas of a predetermined concentration is fine with an average particle size of 0.01 to 200 μm. It is made to contain in a bubble, is dissolved in waste_water | drain, and it inject | pours in the reaction tank 6 from the waste_water | drain injection port 10. FIG. Thereby, the pollutant in the wastewater adheres to the fine bubbles and floats and separates, and bubbles with countless pollutants adhering to the upper part of the reaction tank 6 appear. At this time, the concentration of ozone gas supplied into the system is adjusted to an optimum amount so that the detection value of the ozone concentration detection device 28 disposed in the exhaust gas pipe 27 is not more than a predetermined reference value.
Next, the reaction tank second pump 15 is driven to discharge the waste water from the defoaming nozzle 16. Thereby, the foam expressed above the reaction tank 6 is extinguished, and the polluted substance adhering to the foam is suspended again in the waste water. By repeating this, the oxidative decomposition of the pollutant in the wastewater by ozone is repeated.
After injecting ozone gas of a predetermined concentration into the reaction tank 6 for a predetermined time, the reaction tank first pump 11, the reaction tank ozone gas supply unit 12, and the oxygen gas generation unit 13 are stopped. Next, in the discharge process, the sludge valve 18 is opened and the sludge pump 19 is driven to discharge the sludge settled at the bottom of the reaction tank 6 from the sludge slurry discharge section 17 to the outside of the reaction tank 6 as sludge slurry. . Further, the bubble discharging pump 22 is driven to discharge the bubbles with the contaminated substances from the bubble discharging portion 21 to the outside of the reaction tank 6. Next, after the treated water discharge valve 24 is opened, the treated water discharge pump 25 is driven to discharge the treated water from which the sludge slurry and bubbles have been removed from the treated water discharge unit 23 from the reaction tank 6.
In the dehydration process, the treated water is discharged into a river after the solid content is removed by the solid-liquid separator 26. The solid content separated and dehydrated by the solid-liquid separator 26 is subjected to treatments such as fertilization, fermentation, and water content adjustment as necessary, and can be used as a soil improvement material. Further, the sludge slurry discharged from the sludge slurry 17 is dehydrated by the solid-liquid separator 20 and the solid content is collected. This solid content can also be used as a soil conditioner.
[0031]
As described above, since the waste water treatment apparatus according to Embodiment 1 is configured, the following operation is obtained.
(1) A reaction tank in which wastewater is stored, a reaction layer first communication part communicating with the reaction tank, a reaction tank first pump disposed in the reaction layer first communication part, and ozone gas are supplied into the system. A reaction tank ozone gas supply unit, so that ozone gas is diffused and supplied to the waste water in the reaction tank and the first communication part of the reaction tank to oxidize organic matter in the waste water by the oxidizing power of ozone. Decomposition, oxidation / precipitation of metal ions, deodorization, decolorization, sterilization, etc. of wastewater are performed, and clean treated water that is significantly lower than the wastewater standard can be obtained.
(2) Since ozone gas is supplied to the upstream side of the reaction tank first pump, the supplied ozone gas can be diffused as fine bubbles in the waste water by the impeller of the reaction tank first pump. Moreover, since the waste water is circulated by providing the reaction layer first communicating portion, the waste water is stirred in the reaction tank, and the waste water is accompanied by the fine bubble ozone gas and repeatedly comes into contact with the ozone gas to improve the oxidative decomposition and sterilization efficiency.
(3) Since ozone gas is contained in fine bubbles having an average particle size of 0.01 to 200 μm and supplied into the wastewater, the residence time of ozone in the wastewater can be extended and the solubility in the wastewater can be increased to oxidize. The decomposition reaction can be activated, and further, it can adhere to the pollutant in the wastewater and float and be separated, so that the wastewater treatment efficiency can be increased.
(4) Oxidative decomposition of ozone causes organic substances such as proteins in sludge to be oxidized and solubilized, and the viscosity of sludge decreases due to decomposition of proteins that develop viscosity. The concentration of sludge can be improved and the amount of sludge generated can be greatly reduced.
(5) Since oxidative decomposition is performed using ozone gas, treated water with stable and good water quality can be obtained even with respect to fluctuations in the quality of inflow water, the amount of water, and changes in environmental conditions such as climate.
(6) Since oxygen is generated by oxidative decomposition using ozone, secondary environmental pollution is not caused in the surrounding environment, and treated water and sludge are sterilized by the strong oxidizing power of ozone and are sanitary. Furthermore, since the treated water has been changed to an aerobic water quality due to the oxidizing power of ozone, it can be discharged into rivers and the like, and can also be injected into a biodegradation tank as a pretreatment for biological treatment.
(7) Since the structure of the equipment is simple, construction costs and operation management costs can be reduced, and the equipment load can be reduced. In addition to large-scale wastewater treatment in suburban areas and factories, It can be used as a small-scale wastewater treatment device that performs wastewater treatment for each source of polluted water or small villages in rural areas. In addition, since a large site area is not required for installation, it can be used as a mobile wastewater treatment apparatus that is mounted on a vehicle or the like and circulates a polluted water generation source or a small village, and is excellent in versatility.
(8) Since the reaction tank second communication part, the reaction tank second pump disposed in the reaction tank second communication part, and the defoaming nozzle connected to the reaction tank second communication part, The pollutant that adheres to the injected fine bubbles and floats and separates can be defoamed by spraying the drainage from the defoaming nozzle, and the pollutant can be suspended again in the drainage. As a result, the pollutant is repeatedly brought into contact with ozone gas, the decomposition of the pollutant is promoted, and the wastewater treatment efficiency can be increased.
(9) Since the sludge slurry discharge part and the exhaust bubble part are provided, the sludge deposited on the bottom of the reaction tank after the ozone treatment of the waste water and the sludge adhering to the fine bubbles are separated from the treated water outside the reaction tank. The sludge in the waste water can be separated and concentrated.
(10) Since the oxygen gas generator is connected to the reaction tank ozone gas supply unit, the ozone gas concentration is increased by forcibly increasing the oxygen concentration in the air and supplying high concentration oxygen to the reaction tank ozone gas supply unit. be able to. Thereby, the ozone generation amount supplied to a reaction tank and the reaction tank 1st communication part can be raised, and the oxidative decomposition efficiency of waste_water | drain can be improved. Further, an appropriate amount of ozone gas can be generated according to the amount of organic matter contained in the polluted water, and the processing efficiency can be increased.
(11) Since the ozone concentration detector is provided in the exhaust gas pipe, the ozone gas concentration generated from the reaction vessel ozone gas supply unit is adjusted so that the ozone gas concentration in the exhaust gas becomes almost zero, and is necessary for the oxidation reaction. An optimal amount of ozone can be supplied into the wastewater, and the ozone can be used for wastewater treatment without waste.
[0032]
In the present embodiment, the case where a vortex turbine pump is used as the reaction tank first pump 11 and used as the fine bubble generating means has been described, but instead, the reaction on the downstream side of the reaction tank first pump 11 is performed. There may be a case where fine bubble generating means 8a having an ejector is disposed in the tank first communicating portion 8. As a result, ozone can be sucked in by the negative pressure generated by the waste water jet injected from the waste water inlet 10, and fine bubbles can be generated in the waste water by the shearing action acting on the gas flow. In addition, a fine bubble generator (manufactured by Bubble Tank Co., Ltd.) can be disposed downstream of the reaction tank first pump to generate fine bubbles having a finer bubble diameter.
Further, the case where the drain suction port 9 formed at one end of the reaction tank first communication part 8 communicates with the upper part of the reaction tank 6 has been described, but the drain suction port 9 is connected to a predetermined part below or above the reaction tank 6. In some cases, the waste water in the reaction tank 6 is suctioned by communication. Further, the drain inlet 10 and the drain suction port 9 can be communicated with a plurality of locations in the reaction tank 6. Thereby, the circulation efficiency of drainage can be improved.
[0033]
(Embodiment 2)
FIG. 2 is a schematic diagram of a wastewater treatment apparatus according to Embodiment 2 of the present invention. In addition, the same thing as Embodiment 1 attaches | subjects the same code | symbol, and abbreviate | omits description.
In the figure, 30 is a waste water treatment device in the second embodiment, 31 is a cooling device that is disposed on the side wall of the reaction tank 6 and maintains the waste water in the reaction tank 6 at a water temperature of 28 ° C. or less, preferably 20 ° C. or less. Jacket 32, a treatment tank to which sludge slurry discharge unit 17 and bubble removing unit 21 are connected, 33 a treatment tank first communication part communicating with the upper and lower parts of treatment tank 32, and 33 a a reaction tank first communication part 33. The fine bubble generating means provided with an ejector disposed in a sludge suction port for sucking sludge slurry formed at one end of the treatment tank first communication portion 33 and supplied to the treatment tank 32, and 35 is a treatment tank first. A sludge injection port formed at the other end of the communication portion 33 for injecting the sludge slurry sucked from the sludge suction port 34 into the treatment tank 32, 36 is disposed in the treatment tank first communication portion 33, and the sludge slurry is supplied to the sludge suction port. 34 to sludge inlet 35 The circulating treatment tank first pump 37 is connected to the fine bubble generating means 33a disposed in the treatment tank first communication portion 33 on the upstream side of the treatment tank first pump 36, and oxygen is ozone gas by a silent discharge type ozonizer or the like. The treatment tank ozone gas supply unit 38 supplies ozone into the system, ozone together with air or oxygen, or ozone, and produces high-concentration oxygen as a raw material of ozone from the air using zeolite or the like to the treatment tank ozone gas supply unit 37. The oxygen gas generating unit 39 to be supplied has a second communicating portion where one end communicates with the lower side of the processing bath 32 and the other end communicates with the upper side of the treating bath 32, and 40 is disposed in the second communicating portion 39 of the processing bath. The treatment tank second pump for circulating the sludge, 41 is connected to the other end of the treatment tank second communication portion 39 and disposed at the upper part of the treatment tank 32, and 42 is connected to the treatment tank 32 and is connected to the slurry. The first sludge discharge section for discharging the sludge in the form of a sludge, 43 is a first sludge discharge valve disposed in the first sludge discharge section 42, and 44 is a second sludge that is connected to the bottom of the treatment tank 32 and discharges the sludge sludge. 46 is a second sludge discharge valve disposed in the second sludge discharge section 44, 46 is a sludge discharge section connected to the first sludge discharge section 42 and the second sludge discharge section 43, and 47 is a sludge discharge section. 46 is a sludge discharge pump disposed in the section 46, 48 is a solid-liquid separator such as a filtration device disposed in the sludge discharge section 46, 49 is an exhaust gas pipe connected to the upper part of the treatment tank 32, and 50 is an exhaust gas pipe 49. An ozone concentration detecting device 51 for measuring the ozone concentration in the exhaust gas, 51 is an exhaust ozone treatment device that is provided in the exhaust gas pipe 49 and contains activated carbon that adsorbs and decomposes ozone in the exhaust gas.
In the second embodiment, as in the first embodiment, instead of the fine bubble generating means 33a provided with the ejector, a vortex turbine pump or the like is used as the treatment tank first pump 36, and the sludge inlet 35 is formed with ozone as fine bubbles. It may be generated from. Thereby, the average bubble diameter of the fine bubble containing ozone can be 0.01-200 micrometers.
[0034]
The point in which the waste water treatment apparatus in Embodiment 2 differs from Embodiment 1 is that the reaction jacket 6 is provided with a cooling jacket 31 as a cooling device, and is connected to the sludge slurry discharge part 17 and the exhaust bubble part 21. The treatment tank 32 is provided with a treatment tank first pump 36 and a treatment tank first communication part 33 provided with a treatment tank ozone gas supply part 37 and a defoaming nozzle 41. And a second communication part 39.
The exhausted foam and sludge slurry treated in the treatment tank 32 are discharged from the first sludge discharge part 42 and the second sludge discharge part 44 to the outside of the treatment tank 32 by driving the sludge discharge pump 47, and the solid-liquid separation device The solid content is collected from the sludge slurry by 48. The collected solid content can be used as a soil conditioner.
[0035]
As described above, since the waste water treatment apparatus in the second embodiment is configured, in addition to the actions described in the first embodiment, the following actions are obtained.
(1) Since the reaction tank is equipped with a cooling device, the temperature of the wastewater can be kept low even in the summer when the temperature is high, and the solubility of ozone is increased to improve the reaction such as oxidative decomposition reaction and improve the wastewater treatment efficiency. be able to. This is because the solubility of ozone in water increases as the water temperature decreases.
(2) Since it is equipped with a treatment tank connected to the sludge slurry discharge section and the exhaust bubble section, the sludge slurry can be oxidatively decomposed using ozone in the treatment tank, and the volume of solid waste such as sludge can be reduced. Can be achieved.
(3) Since sludge settled on the bottom of the reaction tank and sludge that floats and separates by adhering to fine bubbles can be guided to the treatment tank to concentrate and reduce the volume of sludge, the wastewater is discharged in parallel in the reaction tank and the treatment tank. Processing can be advanced and workability is excellent.
[0036]
In the present embodiment, the case where the sludge suction port 34 formed at one end of the treatment tank first communication portion 33 communicates with the upper side of the treatment tank 32 has been described. In some cases, the sludge slurry in the treatment tank 32 is sucked by communicating with a predetermined part below or above. Thereby, even when the amount of sludge slurry stored in the treatment tank 32 is small, ozone treatment can be performed by circulating the sludge slurry in the treatment tank first communication portion 33, and the operability is excellent.
[0037]
(Embodiment 3)
FIG. 3 is a schematic diagram of a wastewater treatment apparatus according to Embodiment 3 of the present invention. In addition, the same thing as Embodiment 1 attaches | subjects the same code | symbol, and abbreviate | omits description.
In the figure, 60 is a wastewater treatment apparatus according to the third embodiment, 61 is connected to the drainage pump 3 at one end, a drainage inflow path through which drainage stored in the drainage storage tank 2 flows, and 62 is disposed in the drainage inflow path 61. A drainage inflow valve 63 is disposed in the drainage inflow passage 61 on the downstream side of the drainage inflow valve 61, and is connected to a drainage inflow passage on the upstream side of the pumping pump 63. Dissolving tank ozone gas supply unit that converts ozone gas into ozone by an ozonizer or the like and supplies ozone or ozone together with air or oxygen into the system, 65 is a dissolving tank ozone gas that produces high-concentration oxygen as a raw material of ozone from air using zeolite or the like An oxygen gas generating unit for supplying to the supply unit 64, 66 is a dissolution tank to which the other end of the drainage inflow passage 61 is connected, 67 is a drainage of the reaction tank 6 at one end connected to the dissolution tank 66. A communication portion connected to the inlet 7, 68 is a communication valve disposed in the communication portion 67, 69 is a drainage transport pump disposed in the communication portion 67 downstream of the communication valve 68, and 70 is disposed in the dissolution tank 66. A cooling jacket provided as a cooling device, 71 a heat insulating member covered by the reaction tank 6, 72 a cooling gas generating part as a cooling device for generating a cooling gas, and 73 a lower side inside the dissolution tank 70 It is the cooling gas injection nozzle as a cooling device arranged in the.
In the present embodiment, as in the first and second embodiments, fine bubble generating means having an ejector (not shown) in the drain inflow passage 61, and a vortex turbine pump that can also be used as the fine bubble generating means as the pressure feed pump 63. Etc., ozone can be generated as fine bubbles. Thereby, the average bubble diameter of the fine bubble containing ozone can be 0.01-200 micrometers.
[0038]
About the waste water treatment equipment in Embodiment 3 comprised as mentioned above, the usage method is demonstrated below.
First, the communication valve 68 disposed in the communication portion 67 is closed and the drainage inflow valve 62 disposed in the drainage inflow passage 61 is opened, and then the drainage pump 3 is driven to collect water in the drainage storage tank 2. Pump up the wastewater. Next, the pressure pump 63 is driven and the oxygen gas generator 65 and the dissolution tank ozone gas supply section 64 are driven to pump the waste water in which fine bubbles containing ozone are dissolved into the dissolution tank 66 from the drain inflow path 61. The waste water in which the fine bubbles are dissolved is pressurized at a pressure of 0.2 to 1 MPa for a predetermined time. Further, in order to increase the solubility of ozone, the melting tank 66 is cooled using the cooling jacket 70.
After a predetermined time has elapsed, the pumping pump 63, the oxygen gas generation unit 65, and the dissolution tank ozone gas supply unit 64 are stopped, the communication valve 68 is opened, and the drainage transport pump 69 is further driven to drive the inside of the dissolution tank 66. The waste water is transported into the reaction tank 6. Thereby, the waste water pressurized in the dissolution tank 66 and dissolved in a supersaturated state of ozone is discharged to the reaction tank 6 under atmospheric pressure. At this time, a large amount of dissolved fine bubbles appear in the reaction tank 6 and the pollutant is floated and separated. After the water level of the drainage in the reaction tank 6 reaches a position higher than the drainage suction port 9, the drainage transport pump 69 is stopped and the communication valve 68 is closed.
Next, the reaction tank first pump 11 is driven to circulate the waste water, and the oxygen gas generation unit 13 and the reaction tank ozone gas supply unit 12 are driven to remove fine bubbles containing ozone from the drain inlet 10 into the reaction tank 6. The waste water is treated with ozone in the reaction tank 6. When the temperature of the waste water is high, in order to increase the solubility of ozone in the waste water in the reaction tank 6, a cooling gas is injected into the waste water from the cooling gas injection nozzle 73 and the temperature of the waste water is a low temperature of 28 ° C. or less, preferably 20 ° C. or less. To maintain.
Since the subsequent usage method of the waste water treatment apparatus is the same as that described in the first embodiment, the description thereof is omitted.
[0039]
As described above, since the waste water treatment apparatus in the third embodiment is configured, in addition to the actions described in the first embodiment, the following actions are obtained.
(1) A dissolution tank connected to the drainage inlet, a pressure pump disposed in the drainage inflow passage to pressurize the wastewater and pressurize the inside of the dissolution tank, and a fine bubble connected to the drainage inflow passage and supplied to the drainage And a dissolution tank ozone gas supply unit for generating the ozone gas contained therein, so that the waste water is pressurized in the dissolution tank, ozone can be dissolved in a supersaturated state, and the oxidative decomposition efficiency by ozone can be enhanced.
(2) Since the waste water that was pressurized in the dissolution tank at a pressure of 0.2 to 1 Pa and dissolved in a supersaturated state of ozone is discharged to the reaction tank under atmospheric pressure, a large amount of dissolved ozone appears as fine bubbles. In addition, the floating separation and oxidative decomposition reaction of the pollutant are immediately performed, so that the wastewater treatment time can be remarkably shortened and the workability is excellent.
(3) Since the reaction tank and dissolution tank are equipped with a cooling device and a heat insulating member, the water temperature of the waste water can be kept low even in summer when the temperature is high, and the solubility of ozone is lowered and the oxidative decomposition reaction becomes poor. It can prevent that processing efficiency falls.
[0040]
(Embodiment 4)
FIG. 4 is a schematic diagram of a wastewater treatment apparatus according to Embodiment 4 of the present invention. In addition, the same thing as Embodiment 1 attaches | subjects the same code | symbol, and abbreviate | omits description.
In the figure, 80 is a wastewater treatment apparatus in the fourth embodiment, 81 is a wastewater supply path in which the drainage pump 3 is connected to one end, 82 is a drainage supply path 81 that is branched into a plurality, and the other end is a plurality of wastewater treatment apparatuses 1. The branch supply path 83 is connected to the branch supply path 82, the branch supply valve 84 is disposed in the branch supply path 82, a plurality of branch treated water discharge sections 84 having one end connected to each of the waste water treatment apparatuses 1, and the plurality 85 are disposed. A treated water discharge unit 86 where the branched treated water discharge unit 84 converges, and a solid-liquid separation device 86 such as a filtration device disposed in the treated water discharge unit 85.
[0041]
The point in which the waste water treatment apparatus in Embodiment 4 differs from Embodiment 1 is that the waste water supply path 81 is branched and a plurality of waste water treatment apparatuses 1 are arranged in parallel.
[0042]
As described above, since the waste water treatment apparatus according to the fourth embodiment is configured, the following actions are obtained in addition to the actions described in the first embodiment.
(1) Since a plurality of wastewater treatment devices are arranged in parallel, wastewater treatment can be performed by sequentially supplying untreated wastewater to a wastewater treatment device that has finished wastewater treatment and discharged treated water, Waste water treatment capacity can be significantly increased.
[0043]
【Example】
Hereinafter, the present invention will be specifically described by way of examples. The present invention is not limited to these examples.
(Example 1)
The wastewater treatment effect was confirmed using the wastewater treatment apparatus described in the first embodiment. As the wastewater, the wastewater pumped up from the bottom of the sedimentation tank of the Ezaki Village Wastewater Purification Center in Tamanagawa Town, Yamaguchi Prefecture was used. The Ezaki settlement drainage purification center in Tamanagawa-cho, Yamaguchi Prefecture uses a screen to remove large impurities in the wastewater collected from each household, and then passes sludge and effluent water through a flow adjustment tank, contact aeration tank, and sedimentation tank. The wastewater is treated separately. The sedimentation tank precipitates and separates sludge separated from the contact material filled in the contact aeration tank, and the waste water pumped from the lower part of the sedimentation tank contains a large amount of sludge.
After 200 L of this waste water was stored in a reaction tank having a capacity of 250 L, the reaction tank ozone gas supply unit, the oxygen gas generation unit, and the reaction tank first pump were driven to supply fine bubbles containing ozone into the waste water. At this time, the ozone generation amount is 9.98 g / h, and the ozone gas concentration is 20.8 g / Nm.³Met. The concentration of ozone gas contained in the exhaust gas is 0 g / Nm.³Met. Furthermore, the 2nd pump of the reaction tank was driven, the waste water was sprayed from the defoaming nozzle, and the pollutant which adhered to the foam and floated and separated was repeatedly suspended in the waste water. Treated water is collected from the reaction tank at every elapsed time (treatment time) (every 0, 20, 50, 120 minutes) from the start of supplying fine bubbles containing ozone into the waste water, and suspended matter (SS ), BOD, COD, total nitrogen (hereinafter referred to as TN), and BOD of the filtrate filtered using glass fiber filter paper (GFP) having a pore size of 1 μm (hereinafter referred to as BOD)._SCOD of the filtrate (hereinafter referred to as COD)_SAmmoniacal nitrogen (NH)₄ ⁺-N), nitrate nitrogen (NO₃ ⁻-N), nitrite nitrogen (NO)₂ ⁻-N) was measured. BOD, COD (according to potassium permanganate oxidation method), TN, NH₄ ⁺-N, NO₃ ⁻-N, NO₂ ⁻-N was measured according to JIS K0102. Also, BOD_S, COD_SThe measurement was performed according to JIS K 0102 except for the filtration operation of the sample. The SS was measured according to the Environmental Agency Notification No. 59 of 1971.
In addition, the ozone injection rate in the wastewater treatment for 120 minutes was 99.8 mg / L. The temperature of the wastewater was 20 ° C.
[0044]
FIG. 5 is a diagram showing the relationship between the treatment time and SS, BOD, and COD in the treated water, and FIG. 6 shows the treatment time and TN, BOD in the treated water._S, COD_S, NH₄ ⁺It is the figure which showed the relationship of -N. Table 1 shows NO in treated water against treatment time.₃ ⁻-N, NO₂ ⁻It is the table | surface which showed the quantity of -N.
[Table 1]

From FIG. 5 to FIG. 6, SS, BOD, COD, TN, BOD in treated water in a treatment time of 120 minutes._S, COD_S, NH₄ ⁺It was confirmed that -N can be significantly reduced. In addition, each measured value 120 minutes after processing time is SS: 8.0 mg / L, BOD: 10.4 mg / L, COD: 10.6 mg / L, TN: 14.8 mg / L, BOD_S: 10.2 mg / L, COD_S: 8.5 mg / L, NH₄ ⁺-N: 0.34 mg / L.
In FIG. 6, BOD_S, COD_SWhen the value of is temporarily increased over the treatment time of 20 to 50 minutes, it indicates that the pollutant changed into a soluble substance that can pass through the filter paper by the oxidation of ozone, and then decomposed. I guess. In Table 1, NO is determined after 120 minutes of processing time.₃ ⁻-N, NO₂ ⁻The amount of -N increases because of the oxidizing action of ozone.₄ ⁺It is assumed that the decomposition of -N has progressed.
According to the drainage standards required by the Sewerage Law Enforcement Ordinance, BOD is set to 20 mg / L or less and SS is set to 70 mg / L or less by secondary treatment (specifically, treatment centered on the activated sludge method, sprinkling filtration method, etc.). Therefore, according to the present Example, it became clear that clean treated water significantly lower than the wastewater standard can be obtained by floating separation by ozone fine bubbles having strong oxidizing action and decomposition of pollutants.
[0045]
(Example 2)
The wastewater treatment effect was confirmed using the wastewater treatment apparatus described in the second embodiment. As the wastewater, the wastewater pumped up from the bottom of the sedimentation tank of the Ezaki Village Wastewater Purification Center in Tamanagawa Town, Yamaguchi Prefecture was used.
After the waste water 200L is stored in a reaction tank having a capacity of 250L, the temperature of the waste water in the reaction tank is maintained at 25 ° C. using a cooling jacket, and then the reaction tank ozone gas supply unit, oxygen gas generation unit, reaction tank first One pump was driven to supply fine bubbles containing ozone into the waste water. At this time, the ozone generation amount is 61.6 g / h, and the ozone gas concentration is 68.5 g / Nm.³Met. The concentration of ozone gas contained in the exhaust gas is 0 g / Nm.³Met. Furthermore, the 2nd pump of the reaction tank was driven, the waste water was sprayed from the defoaming nozzle, and the pollutant which adhered to the foam and floated and separated was repeatedly suspended in the waste water. After supplying fine bubbles containing ozone into the wastewater for 30 minutes (treatment time 30 minutes), collect the treated water and the waste gas and sludge slurry (hereinafter referred to as waste air and waste sludge) from the reaction tank. PH, dissolved oxygen (DO), BOD, COD, BOD_S, COD_S, Suspended matter (SS), volatile suspended matter (VSS), evaporation residue (residue after drying at 105-110 ° C. for 2 hours), loss on ignition (evaporation residue was ignited at a high temperature of about 800 ° C. Weight loss), total nitrogen (TN), ammoniacal nitrogen (NH₄ ⁺-N), nitrate nitrogen (NO₃ ⁻-N), nitrite nitrogen (NO)₂ ⁻-N), total phosphorus (TP), Cu, general bacterial count, and E. coli count. BOD, COD (according to potassium permanganate oxidation method), TN, NH₄ ⁺-N, NO₃ ⁻-N, NO₂ ⁻-N was measured according to JIS K0102. Also, BOD_S, COD_SThe measurement was performed according to JIS K 0102 except for the filtration operation of the sample. The SS was measured according to the Environmental Agency Notification No. 59 of 1971. Other analytical procedures were in accordance with the sewage test method. In addition, the ozone injection rate in the wastewater treatment for 30 minutes was 308 mg / L.
After all the waste water and sludge slurry in the reaction tank and treatment tank are discharged, 200 L of waste water pumped up from the sedimentation tank of the Ezaki settlement drainage purification center in Tamankawa-cho, Yamaguchi is stored in the same reaction tank, and then cooled. The temperature of the waste water in the reaction vessel was maintained at 20 ° C. using a jacket for the reactor. Next, the same treatment was performed for 30 minutes, and then treated water was collected and subjected to the same analysis. These analytical values were compared with those of untreated wastewater. The results are shown in Table 2.
[Table 2]

[0046]
From Table 2, the following became clear.
(1) By maintaining the water temperature of the waste water at 20 ° C., it was confirmed that the pH of the treated water was lowered and the amount of dissolved oxygen was increased as compared with the case where it was maintained at 25 ° C. This indicates that the lower the water temperature, the higher the solubility of ozone and the more active the oxidative decomposition. Moreover, it became clear that it shows about 10 times as high value compared with the amount of dissolved oxygen of waste water (raw water). This indicates that the treated water, foam and mud have changed to aerobic water and soil quality.
(2) By maintaining the temperature of the waste water at 20 ° C, compared to the case of maintaining at 25 ° C, BOD_S, COD_SWas confirmed to be high. This indicates that since the oxidative decomposition by ozone is activated, the organic matter in the waste water is decomposed to reduce the molecular weight and increase the soluble organic matter.
(3) It was confirmed that the amount of Cu in the treated water was significantly reduced as compared with the waste water. This indicates that Cu ions in the wastewater are oxidized and deposited, separated from the treated water, and contained in the exhausted foam and the mud. As a result, it has been clarified that the solid content collected by dehydrating the treated water has an extremely low content of Cu as a soil contaminant. In addition, it has been clarified that the foam and mud contain a large amount of nutrient salts such as nitrogen and phosphorus, which is suitable for plant cultivation.
(4) It was confirmed that the number of general bacteria and E. coli in the treated water can be reduced to almost zero (the drainage standard required by the Sewerage Law Enforcement Ordinance is secondary treatment, and the number of coliforms is 3000 / cm.³Less than). As a result, it has been clarified that the solid content collected by dehydrating the treated water, the treated water, the waste mud and the discharged foam is aseptic and very sanitary. From these results, it has been shown that solid waste such as excess sludge, which has been mostly landfilled in the past, can be recycled as a soil conditioner, and wastewater can be effectively utilized as a resource.
(5) Compared with wastewater (raw water), the viscosity of treated water is reduced, and the amount of evaporation residue of foam and mud is increased to about 5 times the amount of evaporation residue of wastewater. It was. This indicates that the concentration of exhausted foam / mud is about 5 times as high as that of the wastewater and is remarkably concentrated. As a result, according to the present Example, it became clear that the concentration property of sludge can be improved and the generation amount of solid wastes such as excess sludge can be greatly reduced.
[0047]
【The invention's effect】
As described above, according to the wastewater treatment apparatus of the present invention and the method for producing a soil conditioner using the same, the following advantageous effects can be obtained.
According to the invention of claim 1,
(1) A reaction tank in which wastewater is stored, a reaction layer first communication part communicating with the reaction tank, a reaction tank first pump disposed in the reaction layer first communication part, and ozone gas are supplied into the system. A reaction tank ozone gas supply unit, so that ozone gas is diffused and supplied to the waste water in the reaction tank and the first communication part of the reaction tank to oxidize organic matter in the waste water by the oxidizing power of ozone. It is possible to provide a wastewater treatment apparatus capable of obtaining clean treated water significantly lower than the wastewater standard by performing decomposition, metal ion oxidation / precipitation, wastewater deodorization, decolorization, sterilization, and the like. For this reason, the waste water treatment apparatus excellent in the versatility which can be widely used not only for a process of industrial wastewater etc. but in general water treatments, such as clean water and industrial water, can be provided.
(2) Since ozone gas is supplied to the upstream side of the reaction tank first pump, the supplied ozone gas can be diffused as fine bubbles in the waste water by the impeller of the reaction tank first pump. Moreover, since the waste water is circulated with the reaction layer first communicating portion, the waste water is agitated in the reaction tank, and the waste water is accompanied by the fine bubble ozone gas and repeatedly comes into contact with the ozone gas, thereby improving the waste water treatment efficiency.
(3) Oxidative decomposition of organic matter such as protein in sludge is oxidatively decomposed and solubilized by the oxidative decomposition of ozone, and the viscosity of sludge is reduced by the decomposition of protein that develops viscosity. It is possible to provide a wastewater treatment apparatus that can improve the performance and greatly reduce the amount of sludge generated.
(4) Ozone gas is used for oxidative decomposition, so it is stable enough to obtain treated water with good water quality even against changes in influent water quality, water volume, and environmental conditions such as climate. A waste water treatment apparatus can be provided.
(5) Oxygen is generated by oxidative decomposition using ozone, so it does not cause secondary environmental pollution in the surrounding environment, and it is sterilized by the strong oxidizing power of ozone to obtain sanitary treated water and sludge. A waste water treatment apparatus can be provided. Furthermore, since the treated water has been changed to aerobic water quality due to the oxidizing power of ozone, it can be discharged into rivers, etc., and can also be injected into a biodegradation tank as a pretreatment for biological treatment. A processing device can be provided.
(6) Since the structure of the equipment is simple, construction costs and operation management costs can be reduced, and the equipment load can be reduced. In addition to large-scale wastewater treatment in suburban areas and factories, It is possible to provide a wastewater treatment apparatus that can be used as a small-scale wastewater treatment apparatus that performs wastewater treatment for each polluted water source or small village in an agricultural and mountain village area. In addition, since it does not require a lot of site space for installation, it can be used as a mobile wastewater treatment device that can be mounted on a vehicle or the like to circulate polluted water sources or small villages, etc., and has excellent versatility. An apparatus can be provided.
[0048]
According to invention of Claim 2, in addition to the effect of Claim 1,
(1) Since the fine bubble generating means is disposed in the first communicating portion of the reaction tank, ozone gas can be contained in the fine bubbles and supplied into the waste water, and the residence time of ozone in the waste water can be increased. A wastewater treatment device that can increase the solubility of ozone in the wastewater and activate the oxidative decomposition reaction, and that the pollutant in the wastewater adheres to the fine bubbles and floats and separates and is extremely excellent in wastewater treatment efficiency. Can be provided.
[0049]
According to invention of Claim 3, in addition to the effect of Claim 1 or 2,
(1) Since it comprises a reaction tank second communication part, a reaction tank second pump disposed in the reaction tank second communication part, and a defoaming nozzle connected to the reaction tank second communication part, The pollutant that adheres to the injected fine bubbles and floats and separates can be defoamed by spraying the drainage from the defoaming nozzle, and the pollutant can be suspended again in the drainage. Moreover, it is possible to repeatedly contact the wastewater droplets or the like with the ozone gas layer above the reaction tank. Accordingly, it is possible to provide a wastewater treatment apparatus with high wastewater treatment efficiency in which the pollutant is repeatedly contacted with ozone gas and the decomposition of the pollutant is promoted.
[0050]
According to the invention of claim 4, in addition to the effect of any one of claims 1 to 3,
(1) Since the reaction tank is equipped with a cooling device and a heat insulating member, the temperature of the waste water can be kept low even in the summer when the temperature is high, and the waste water treatment efficiency is improved by increasing the solubility of ozone and improving the reaction such as oxidative decomposition reaction. High wastewater treatment equipment can be provided.
[0051]
According to invention of Claim 5, in addition to the effect of any one of Claims 1 to 4,
(1) Since the water temperature of the waste water in the reaction tank is maintained at a low temperature, a waste water treatment apparatus excellent in stability capable of preventing a decrease in the solubility of ozone and obtaining a stable waste water treatment efficiency is provided. be able to.
[0052]
According to invention of Claim 6, in addition to the effect of any one of Claims 1 to 5,
(1) Since it has a sludge slurry discharge part and a drainage part, the sludge deposited on the bottom of the reaction tank after the ozone treatment of the waste water and the sludge adhering to fine bubbles are separated from the treated water outside the reaction tank. Therefore, it is possible to provide a waste water treatment apparatus that can separate and concentrate sludge in the waste water, has high concentrating properties, and generates less solid waste.
[0053]
According to invention of Claim 7, in addition to the effect of Claim 6,
(1) Since it has a treatment tank connected to the sludge slurry discharge section and the exhaust bubble section, sludge discharged from the reaction tank can be further oxidized and decomposed using ozone in the treatment tank, and solids such as sludge It is possible to provide a wastewater treatment apparatus capable of reducing waste volume.
(2) Since sludge settled on the bottom of the reaction tank and sludge that floats and separates by adhering to fine bubbles can be guided to the treatment tank to concentrate and reduce the volume of sludge, waste water is discharged in parallel in the reaction tank and the treatment tank. It is possible to provide a wastewater treatment apparatus that can proceed with the treatment and is excellent in workability.
[0054]
According to invention of Claim 8 of this invention, in addition to the effect of any one of Claims 1 thru | or 7,
(1) a dissolution tank connected to the drainage inlet, a pressure pump disposed in the drainage inflow path to pressurize the wastewater and pressurize the inside of the dissolution tank, a dissolution tank ozone gas supply unit connected to the drainage inflow path, Since the waste water is pressurized in the dissolution tank and ozone can be dissolved in a supersaturated state, a waste water treatment apparatus that can improve the oxidative decomposition efficiency by ozone can be provided.
(2) Since the wastewater that has been pressurized in the dissolution tank and dissolved in a supersaturated state of ozone is released into the reaction tank under atmospheric pressure, a large amount of dissolved ozone appears as fine bubbles, and the floating separation and oxidation of pollutants It is possible to provide a wastewater treatment apparatus that can perform the decomposition reaction immediately and can significantly reduce the wastewater treatment time and is excellent in workability.
[0055]
According to invention of Claim 9 of this invention,
(1) Since the ozone-treated treated water or sludge slurry is dehydrated and the solid content is collected, a method for producing a soil amendment that can produce aseptic and hygienic soil amendment without bacteria such as Escherichia coli is provided. can do. Moreover, since the dissolved oxygen amount of treated water etc. is remarkably high, the manufacturing method of the soil improvement material which can manufacture the soil improvement material suitable for cultivation of a crop with high aerobic property of solid content and soil bacteria etc. is easy to propagate is provided. Can do. Moreover, the manufacturing method of the soil improvement material which can manufacture the soil improvement material with little content of soil pollutants, such as copper, cadmium, and zinc, can be provided from the solid content extract | collected by dehydrating the treated water.
(2) The solid content obtained by solid-liquid separation of the treated water can provide a method for producing a soil conditioner suitable for cultivation of crops because the organic matter is decomposed and contains nitrogen, phosphorus and the like.
(3) Since it has been changed to an aerobic soil due to the oxidizing power of ozone, it can be easily composted after adding organic matter such as rice husk and straw and can be used to produce a soil improver with excellent versatility. A method for producing an improved material can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a wastewater treatment apparatus in Embodiment 1. FIG.
FIG. 2 is a schematic diagram of a wastewater treatment apparatus according to Embodiment 2.
FIG. 3 is a schematic diagram of a wastewater treatment apparatus according to Embodiment 3.
4 is a schematic diagram of a wastewater treatment apparatus according to Embodiment 4. FIG.
FIG. 5 is a diagram showing the relationship between treatment time and SS, BOD, COD in treated water
[Figure 6] Treatment time and TN, BOD in treated water_S, COD_S, NH₄ ⁺-N relationship diagram
[Explanation of symbols]
1 Wastewater treatment equipment
2 Drainage storage tank
3 Drainage pump
4 Drain supply channel
5 Drain supply valve
6 Reaction tank
7 Drainage inlet
8 Reaction tank 1st communication part
9 Drainage suction port
10 Drainage inlet
11 Reaction tank first pump
12 Reaction tank ozone gas supply section
13 Oxygen gas generator
14 Reaction tank 2nd communication part
15 Reaction tank second pump
16 Defoaming nozzle
17 Sludge slurry discharge section
18 Mud valve
19 Mud pump
20 Solid-liquid separator
21 Foaming part
22 Foam pump
23 treated water discharge section
24 Treated water discharge valve
25 treated water discharge pump
26 Solid-liquid separator
27 Exhaust gas pipe
28 Ozone concentration detector
29 Waste ozone treatment device
30 Wastewater treatment equipment
31 Cooling jacket
32 Treatment tank
33 Treatment tank 1st communication part
33a Fine bubble generation means
34 Sludge suction port
35 Sludge inlet
36 Treatment tank first pump
37 Treatment tank ozone gas supply part
38 Oxygen gas generator
39 Treatment tank 2nd communication part
40 Treatment tank second pump
41 Defoaming nozzle
42 1st sludge discharge part
43 1st sludge discharge valve
44 Second sludge discharge section
45 Second sludge discharge valve
46 Sludge discharge section
47 Sludge discharge pump
48 Solid-liquid separator
49 Exhaust gas pipe
50 ozone concentration detector
51 Waste ozone treatment equipment
60 Wastewater treatment equipment
61 Drainage inflow channel
62 Drainage inflow valve
63 Pressure feed pump
64 Dissolution tank ozone gas supply section
65 Oxygen gas generator
66 Dissolution tank
67 Communication Department
68 communication valve
69 Wastewater transport pump
70 Cooling jacket
71 Heat insulation material
72 Cooling gas generator
73 Cooling gas injection nozzle
80 Wastewater treatment equipment
81 Drain supply channel
82 Branch supply path
83 Branch supply valve
84 Branched water discharge section
85 treated water discharge unit
86 Solid-liquid separator

Claims (9)

A reaction tank having a drainage inlet and storing drainage; a drainage suction port at one end; a drainage inlet at the other end; and a reaction tank first communication part communicating with the reaction tank; and the reaction tank first communication A reaction tank first pump that circulates waste water disposed in the unit, a reaction tank ozone gas supply unit that is connected to the reaction tank first communication part upstream of the reaction tank first pump and supplies ozone gas into the system; A wastewater treatment apparatus comprising: The waste water treatment apparatus according to claim 1, wherein fine bubble generating means is disposed in the first communication portion of the reaction tank. A reaction tank second communication part whose one end communicates with a predetermined part of the reaction tank and the other end communicates with an upper part of the reaction tank, and a reaction tank second which is disposed in the reaction tank second communication part and circulates waste water. The wastewater treatment apparatus according to claim 1 or 2, further comprising a pump and a defoaming nozzle connected to the other end of the second communication portion of the reaction tank. The waste water treatment apparatus according to any one of claims 1 to 3, further comprising a cooling device disposed in the reaction tank and / or a heat insulating member covering the reaction tank. The waste water treatment apparatus according to any one of claims 1 to 4, wherein the temperature of the waste water in the reaction tank is maintained at 28 ° C or lower, preferably 20 ° C or lower. The sludge slurry discharge part connected to the predetermined part of the bottom part or the side part of the said reaction tank, and / or the bubble removal part connected to the predetermined part above the said reaction tank, It is characterized by the above-mentioned. The waste water treatment apparatus of any one of thru | or 5. A treatment tank connected to the sludge slurry discharge part and / or the bubble removing part; a treatment tank first communication part in which a sludge suction port is formed at one end and a sludge injection port is formed at the other end; A treatment tank first pump that is disposed in the treatment tank first communication section and circulates sludge; and a treatment tank ozone gas supply section connected to the treatment tank first communication section on the upstream side of the treatment tank first pump; The waste water treatment apparatus according to claim 6, wherein the waste water treatment apparatus is provided. A dissolution tank connected to the drainage inlet, a drainage inflow path connected to the dissolution tank to allow wastewater to flow into the dissolution tank, and disposed in the drainage inflow path to pump wastewater and add to the inside of the dissolution tank. The wastewater according to any one of claims 1 to 7, further comprising: a pressure pump for compressing, and a dissolution tank ozone gas supply unit connected to the drainage inflow passage upstream of the pressure pump. Processing equipment. An ozone treatment process for supplying ozone gas while circulating the wastewater stored in the reaction tank using the wastewater treatment apparatus according to any one of claims 1 to 8, and ozone treatment of the wastewater, and the ozone treatment process. A discharge step of discharging the treated water and sludge slurry from the reaction tank, and a solid content used alone or in combination as a soil conditioner by dehydrating the discharged treated water and / or sludge slurry. And a dehydration treatment step for collecting the soil.

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