JP2004261729A

JP2004261729A - Water treatment system, and water treatment method

Info

Publication number: JP2004261729A
Application number: JP2003055511A
Authority: JP
Inventors: Noritaka Shibata; 規孝柴田; Kazushi Kondo; 和史近藤; Shinka Cho; 振家張
Original assignee: Mitsubishi Rayon Co Ltd
Current assignee: Mitsubishi Rayon Co Ltd
Priority date: 2003-03-03
Filing date: 2003-03-03
Publication date: 2004-09-24
Anticipated expiration: 2023-03-03
Also published as: JP4105006B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water treatment system and a water treatment method by which an objective substance in the water to be treated can be removed at low cost without remarkably varying treatment capacity in accordance with water temperature. <P>SOLUTION: An object substance in the water to be treated is adsorbed on an adsorbent by a first adsorption treatment device 11 and a second adsorption treatment device 12. The water subjected to the treatment by the adsorption treatment devices is biologically treated by a catalytic oxidation device 13 (biological treatment means). The amount of the adsorption agent charged to the water in the second adsorption treatment device 12 is controlled in accordance with the water temperature of the water measured by a temperature sensor 20 in the catalytic oxidation device 13. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、水処理システムおよび水処理方法に関し、特に、食品工場、アルコール工場、畜産施設等からの排出される、窒素、リンを高濃度に含む排水を処理するための水処理システムおよび水処理方法に関する。
【０００２】
【従来の技術】
排水中に含まれるアンモニア性窒素（ＮＨ_４ −Ｎ）を除去する方法としては、（ｉ）排水をｐＨ１０以上のアルカリ性にして瀑気し、アンモニア性窒素をアンモニアガスとして放出するエアストリッピング法、（ｉｉ）塩素ガスの酸化力でアンモニア性窒素を窒素ガスに酸化する塩素注入法、（ｉｉｉ）無機イオン交換体にアンモニア性窒素を吸着させるイオン交換吸着法、（ｉｖ）亜硝化菌、硝化菌によりＮＨ_４ ^＋をＮＯ_２ ⁻、ＮＯ_３ ⁻に酸化（硝化）し、さらに脱窒菌により窒素ガスとする生物学的硝化脱窒法、などがこれまでに提案されている。
【０００３】
しかしながら、上述したアンモニア性窒素の除去方法のうち、（ｉ）エアストリッピング法および（ｉｉ）塩素注入法は、使用する薬品の量が多く、処理コストが高くなるという問題を有していた。また、（ｉｉ）塩素注入法は、処理水中の残留塩素の問題も有していた。
【０００４】
（ｉｉｉ）イオン交換吸着法は、処理時間の短さから近年、開発が進められており、ゼオライトによるアンモニア性窒素の選択的吸着性に着目した方法が、いくつか開示されている。
特開平６−２６９７７６号公報には、排水中のアンモニア性窒素を、吸着処理槽内のゼオライトに吸着させる方法が開示されている。しかしながら、この方法では、ゼオライト自身のアンモニア吸着容量が非常に少ないため、処理能力が不十分であるという問題があった。
【０００５】
特開平１１−２３９７８５号公報には、ゼオライトのナトリウムイオン、カリウムイオンの一部をマグネシウムイオンで置換した置換ゼオライトを用いる方法が開示されている。この方法によれば、排水中のアンモニウムイオン濃度が３０ｍｇ／Ｌ以下の濃度であれば、安定した処理が可能である。しかしながら、アンモニウムイオン濃度が３０ｍｇ／Ｌを超える、特に１０００ｍｇ／Ｌ以上となると、置換ゼオライト単位質量あたりに吸着されたアンモニウムイオンが少ない状態で吸着平衡に達してしまうため、置換ゼオライトが本来有する吸着容量を効率よく使うことができず、置換ゼオライトの投入量が増え、処理コストが高くなるという問題があった。
【０００６】
これに対して、（ｉｖ）生物学的硝化脱窒法は、処理コストが安いため広く普及している。しかしながら、この方法では、排水の水温が１５℃以下になると、生物活性が低下し、処理能力が低下するするため、処理時間を延ばす必要があった。このように、（ｉｖ）生物学的硝化脱窒法は、その処理能力が温度に依存するため、安定した処理が難しいという問題があった。
【０００７】
【特許文献１】
特開平６−２６９７７６号公報（第２−５頁）
【特許文献２】
特開平１１−２３９７８５号公報（第２−６頁）
【０００８】
【発明が解決しようとする課題】
よって、本発明の目的は、水温によって処理能力が大きく変動することなく、低コストで被処理水中の対象物質を除去できる水処理システムおよび水処理方法を提供することにある。
【０００９】
【課題を解決するための手段】
すなわち、本発明の水処理システムは、被処理水中の対象物質を吸着剤に吸着させる吸着処理手段と、吸着処理手段で処理された被処理水を生物学的に処理する生物処理手段と、吸着処理手段の被処理水に吸着剤を投入する吸着剤投入手段と、生物処理手段における生物処理の能力を検知する能力検知手段と、能力検知手段で検知された生物処理の能力に応じて吸着剤の投入量を調整する投入量調整手段とを具備することを特徴とするものである。
【００１０】
また、本発明の水処理システムは、前記吸着処理手段を２段以上具備し、さらに、後段側の吸着処理手段で使用した吸着剤を前段側の吸着処理手段に移送する吸着剤移送手段を具備するものであることが望ましい。
また、本発明の水処理システムにおいては、前記能力検知手段は、温度センサであることが望ましい。
【００１１】
また、本発明の水処理方法は、被処理水中の対象物質を吸着剤に吸着させる吸着処理工程と、吸着処理工程で処理された被処理水を生物学的に処理する生物処理工程とを有し、吸着処理工程の被処理水に投入する吸着剤の量を、生物処理工程における生物処理の能力に応じて調整することを特徴とする。
【００１２】
また、本発明の水処理方法は、前記吸着処理工程を２工程以上有し、後工程側の吸着処理工程で使用した吸着剤を前工程側の吸着処理工程で再使用することが望ましい。
また、本発明の水処理方法においては、前記生物処理の能力を、生物処理工程における被処理水の温度から見積ることが望ましい。
【００１３】
【発明の実施の形態】
以下、本発明を詳しく説明する。
（形態例１）
図１は、本発明の水処理システムの一形態例を示す概略構成図である。この水処理システムは、被処理水の流入水量、ｐＨ等を調整する調整槽１０と、被処理水中の対象物質を吸着剤に吸着させる第１の吸着処理装置１１および第２の吸着処理装置１２（吸着処理手段）と、吸着処理装置で処理された被処理水を生物学的に処理する接触酸化装置１３（生物処理手段）と、接触酸化装置１３で処理された被処理水の固液分離を行う加圧浮上分離装置１４と、第２の吸着処理装置１２の被処理水に吸着剤を投入する吸着剤投入装置１５（吸着剤投入手段）と、第２の吸着処理装置１２の被処理水に凝集剤を投入する凝集剤投入装置１６と、第２の吸着処理装置１２で使用した吸着剤を第１の吸着処理装置１１に移送する吸着剤移送装置１７（吸着剤移送手段）と、第１の吸着処理装置１１で使用した吸着剤を回収する吸着剤回収装置１８と、吸着剤回収装置１８で回収された吸着剤を脱水処理する吸着剤脱水装置１９と、接触酸化装置１３における被処理水の水温を測定する温度センサ２０（能力検知手段）と、温度センサ２０で測定された水温に応じて、吸着剤投入装置１５からの吸着剤の投入量、吸着剤移送装置１７による吸着剤の移送量、吸着剤回収装置１８による吸着剤の回収量等を調整する制御装置２１（投入量調整手段）と、調整槽１０から第１の吸着処理装置１１へ被処理水を送液する被処理水供給装置２２とを具備して概略構成されるものである。
【００１４】
第１の吸着処理装置１１は、被処理水と吸着剤とを接触させる部分と吸着剤を沈降分離させる部分とを有する吸着処理槽２３と、吸着処理槽２３内の被処理水を攪拌する攪拌装置２４とを備えたものである。
同様に、第２の吸着処理装置１２は、吸着処理槽２５と、攪拌装置２６とを備えたものであり、第１の吸着処理装置１１で処理された被処理水が重力によって第２の吸着処理装置１２へと流れるように、第１の吸着処理装置１１よりも低い位置に設置されているものである。
【００１５】
接触酸化装置１３は、接触酸化槽２７と、この中に配置された、好気性微生物（汚泥）を付着させる接触材２８と、接触酸化槽２７に空気を供給するブロアポンプ２９と、接触材２８の下方に配置され、ブロアポンプ２９からの空気を接触酸化槽２７内に散気する散気管３０とを備えたものである。
加圧浮上分離装置１４は、加圧によって被処理水内に発生した微細な気泡により被処理水内の汚泥を浮上させ、被処理水を汚泥および処理水に分離するものであり、固液分離槽３１と、固液分離槽３１内の被処理水を加圧する、加圧タンク、加圧ポンプ等の加圧手段（図示略）と、浮上した汚泥を掻き取る、スクレーパー等の掻き取り手段３２とを備えたものである。
【００１６】
吸着剤投入装置１５は、複数の吸着処理装置のうち最後段の吸着処理装置へ吸着剤を投入するものであり、吸着剤を貯留する貯留容器（図示略）と、吸着剤を第２の吸着処理装置１２へ投入するための投入口（図示略）と、投入口に設けられた、吸着剤の投入速度（時間あたりの投入量）を調整する調整機構（図示略）とを備えたものである。
同様に、凝集剤投入装置１６は、複数の吸着処理装置のうち最後段の吸着処理装置へ凝集剤を投入するものであり、凝集剤を貯留する貯留容器（図示略）と、凝集剤を第２の吸着処理装置１２へ投入するための投入口（図示略）と、投入口に設けられた、凝集剤の投入速度（時間あたりの投入量）を調整する調整機構（図示略）とを備えたものである。
【００１７】
吸着剤移送装置１７は、第２の吸着処理装置１２の吸着処理槽２５の底に、凝集剤によって凝集、沈降した吸着剤３３を若干の被処理水とともに回収し、第１の吸着処理装置１１に供給するものである。吸着剤移送装置１７としては、例えば、スクリューポンプ、スネークポンプ、ギアポンプ、カスケードポンプ、チューブポンプなどの中から、吸着剤３３の粘性、濃度、量などに応じて適宜選択して用いることができる。
吸着剤回収装置１８は、第１の吸着処理装置１１の吸着処理槽２３の底に沈降した吸着剤３４を若干の被処理水とともに回収し、吸着剤脱水装置１９に移送するものである。吸着剤回収装置１８としては、例えば、スクリューポンプ、スネークポンプ、ギアポンプ、カスケードポンプ、チューブポンプなどの中から、吸着剤３４の粘性、濃度、量などに応じて適宜選択して用いることができる。
【００１８】
吸着剤脱水装置１９は、第１の吸着処理装置１１から回収された吸着剤から水を脱水し、脱水による排水を調整槽１０に戻し、脱水された吸着剤を得るものである。吸着剤脱水装置１９としては、ロール脱水方式の脱水機、加圧脱水方式の脱水機、真空脱水方式の脱水機などを用いることができる。
温度センサ２０は、接触酸化装置１３における生物処理の能力の尺度の一つである、接触酸化装置１３における被処理水の温度を測定するものである。
被処理水供給装置２２は、調整槽１０から第１の吸着処理装置１１へ被処理水を送液する送液ポンプであり、被処理水供給装置２２としては、例えばマグネットポンプ、渦巻きポンプ、ダイヤフラムポンプ、水中ポンプ、スクリューポンプ、スネークポンプ、ギアポンプ、カスケードポンプ、チューブポンプなどを用いることができる。
【００１９】
制御装置２１は、処理部（図示略）と、インターフェース部（図示略）とを具備して概略構成され、温度センサ２０で測定された水温に応じて、吸着剤投入装置１５からの吸着剤の投入量、吸着剤移送装置１７による吸着剤の移送量、吸着剤回収装置１８による吸着剤の回収量等を調整するものである。
【００２０】
処理部は、温度センサ２０からの温度情報と、被処理水の各水温における接触酸化装置１３の処理能力の測定結果に基づく水温−処理能力関係式とから、接触酸化装置１３の処理能力を見積り、そして、吸着剤投入装置１５からの吸着剤の投入量（投入速度）、吸着剤移送装置１７による吸着剤の移送量（移送速度）、吸着剤回収装置１８による吸着剤の回収量（回収速度）等を決定し、調整するものである。
インターフェイス部は、吸着剤投入装置１５、吸着剤移送装置１７、吸着剤回収装置１８、温度センサ２０等と、処理部との間を電気的に接続するものである。
【００２１】
なお、この処理部は専用のハードウエアにより実現されるものであってもよく、また、この処理部はメモリおよび中央演算装置（ＣＰＵ）によって構成され、処理部の機能を実現するためのプログラムをメモリにロードして実行することによりその機能を実現させるものであってもよい。
また、制御装置２１には、周辺機器として、入力装置、表示装置等が接続されるものとする。ここで、入力装置とは、ディスプレイタッチパネル、スイッチパネル、キーボード等の入力デバイスのことをいい、表示装置とは、ＣＲＴや液晶表示装置のことをいう。
【００２２】
次に、図示例の水処理システムを用いた水処理方法について説明する。
この水処理システムの運転開始時には、まず、第２の吸着処理装置１２に、吸着剤投入装置１５から吸着剤を、凝集剤投入装置１６から凝集剤を、それぞれ、第２の吸着処理装置１２内に所定量投入する。ついで、調整槽１０にて流入水量、ｐＨ等が調整された被処理水を被処理水供給装置２２によって第１の吸着処理装置１１に供給し、第１の吸着処理装置１１から溢れた被処理水を、第１の吸着処理装置１１と第２の吸着処理装置１２との高低差を利用して、第２の吸着処理装置１２に供給する。
【００２３】
ついで、第２の吸着処理装置１２に備えられた攪拌装置２６を作動させて、被処理水と吸着剤とを第２の吸着処理装置１２内で接触させ、被処理水中の対象物質を吸着剤に吸着させる。第２の吸着処理装置１２において所定時間、吸着処理を行った後、吸着剤移送装置１７を作動させ、第２の吸着処理装置１２の吸着処理槽２５の底に、凝集剤によって凝集、沈降した吸着剤３３を若干の被処理水とともに回収し、所定量の吸着剤を第１の吸着処理装置１１に供給し、第１の吸着処理装置１１に備えられた攪拌装置２４を作動させて、被処理水と吸着剤とを第１の吸着処理装置１１内で接触させ、被処理水中の対象物質を吸着剤に吸着させる。
【００２４】
第１の吸着処理装置１１において所定時間、吸着処理を行った後、調整槽１０の被処理水を被処理水供給装置２２によって第１の吸着処理装置１１に所定の供給速度で連続的に供給し、連続運転を開始する。連続運転の際には、吸着剤投入装置１５から吸着剤を、凝集剤投入装置１６から凝集剤を、それぞれ吸着処理装置１２内に所定の投入速度で連続的に供給し、かつ第２の吸着処理装置１２から吸着剤を吸着剤移送装置１７によって回収し、回収した吸着剤を所定の移送速度で第１の吸着処理装置１１に供給する。また、第１の吸着処理装置１１から吸着剤を吸着剤回収装置１８によって所定の回収速度で回収する。ここで、吸着処理装置からの吸着剤の回収は、被処理水の混入量を極力減らすために、断続的に行うことが好ましい。第１の吸着処理装置１１から回収された吸着剤を、吸着剤脱水装置１９にて脱水し、排水を調整槽１０に戻し、脱水された吸着剤を得る。脱水された吸着剤は、再利用または廃棄される。
【００２５】
連続運転の間、被処理水供給装置２２によって調整槽１０から第１の吸着処理装置１１に連続的に供給された被処理水は、まず、第１の吸着処理装置１１において吸着剤と接触し、被処理水中の対象物質が吸着剤に吸着される。吸着処理された被処理水は、第１の吸着処理装置１１から溢れ、第１の吸着処理装置１１と第２の吸着処理装置１２との高低差によって第２の吸着処理装置１２に供給され、第２の吸着処理装置１２において吸着剤と接触し、被処理水中の対象物質が吸着剤に吸着される。
【００２６】
第２の吸着処理装置１２において吸着処理された被処理水は、第２の吸着処理装置１２から溢れ、第２の吸着処理装置１２と接触酸化装置１３との高低差によって接触酸化装置１３に供給され、接触酸化装置１３において生物学的に処理される。具体的には、好気性微生物（汚泥）が付着した接触材２８にブロアポンプ２９からの空気を散気管３０から散気して、空気の存在下、好気性微生物によって対象物質を酸化、分解する。接触酸化装置１３において酸化処理された被処理水は、加圧浮上分離装置１４に供給され、汚泥および処理水に分離される。
【００２７】
吸着剤としては、対象物質が、アンモニア性窒素等の窒素化合物、色素、臭気物質などの場合は、合成ゼオライト、天然ゼオライト、人工ゼオライト等を用いることができる。また、対象物質が、リン化合物の場合は、無機凝集剤、酸化チタン、流用活性アルミナ、ケイ酸チタニウム等を用いることができる。
吸着剤は、粒径が小さいほど表面積が増加するので、平均粒径が０．０１〜５０μｍのものが好ましい。後述の膜分離装置を用いて固液分離を行う場合は、膜の孔径の範囲（膜の透過流速と菌などの阻止性との兼ね合い）から、０．２〜１０μｍの範囲が好ましく、一般的な沈降により固液分離を行う場合は、沈降性、攪拌による旋回性の点から、１〜２０μｍの範囲が好ましい。
【００２８】
吸着剤の投入量（投入速度）は、吸着剤の吸着能、吸着処理後の被処理水に含まれる対象物質の目標濃度、水処理システムで得られる処理水に含まれる対象物質の目標濃度、生物処理手段の処理能力等によって適宜決定される。
本発明においては、特に生物処理手段の処理能力に応じて吸着剤の投入量（投入速度）を調整することに特徴がある。具体的には、制御装置２１において、温度センサ２０からの温度情報と、被処理水の各水温における接触酸化装置１３の処理能力の測定結果に基づく水温−処理能力関係式とから、接触酸化装置１３の処理能力を見積り、そして、制御装置２１によって、吸着剤投入装置１５からの吸着剤の投入量（投入速度）、吸着剤移送装置１７による吸着剤の移送量（移送速度）、吸着剤回収装置１８による吸着剤の回収量（回収速度）等を決定し、調整する。
【００２９】
例えば、被処理水の水温が２０℃の場合に吸着処理および生物処理による対象物質の目標除去率（目標水質）を達成するための吸着剤の投入量（投入速度）を、運転開始時に初期投入量として設定しておく。連続運転中に水温が２０℃より下がった場合、生物活性の低下に伴う接触酸化装置１３の処理能力の低下の度合いに合わせて、吸着剤の投入量（投入速度）を増やし、被処理水の時間あたりの吸着処理量（調整槽１０からの被処理水の供給速度）に対する吸着剤の量を増やす。一方、水温が２０℃より上がった場合、生物活性の上昇に伴う接触酸化装置１３の処理能力の増加の度合いに合わせて、吸着剤の投入量（投入速度）を減らし、被処理水の時間あたりの吸着処理量（調整槽１０からの被処理水の供給速度）に対する吸着剤の量を減らす。なお、吸着剤投入装置１５からの吸着剤の投入量（投入速度）の変化に合わせて、吸着剤移送装置１７による吸着剤の移送量（移送速度）および吸着剤回収装置１８による吸着剤の回収量（回収速度）を調整する必要があることは無論である。
【００３０】
吸着剤を凝集させるための凝集剤としては、無機凝集剤、有機高分子凝集剤、凝集助剤を用いることができる。中でも、使用済みのゼオライトを土壌に還元することが可能であり、廃棄物が発生しないことから、鉄系の無機凝集剤が好適である。
凝集剤の投入量（投入速度）は、無機凝集剤の場合、吸着剤であるゼオライトの沈降性、被処理水中のリン濃度、水処理システムで得られる処理水に含まれるリンの目標濃度等の条件によって、適宜決定すればよい。
有機高分子凝集剤は、無機凝集剤と併用することが好ましく、その投入量は無機凝集剤の場合と同様に適宜決定すればよい。
【００３１】
第１の吸着処理装置１１および第２の吸着処理装置１２における、被処理水の滞留時間は、被処理水中の対象物質の濃度、吸着剤の種類、量などの条件に応じて適宜決定すればよい。この滞留時間は、被処理水供給装置２２による第１の吸着処理装置１１への被処理水の供給速度を調整することにより、調節することができる。
また、接触酸化装置１３における被処理水の滞留時間は、被処理水中の対象物質の濃度、接触酸化槽２７の容積などの条件に応じて適宜決定すればよい。
【００３２】
以上説明した水処理システムにあっては、被処理水中の対象物質を吸着剤に吸着させる吸着処理装置と、吸着処理された被処理水を生物学的に処理する接触酸化装置１３とを併用しているので、吸着処理装置における吸着剤の使用量を吸着処理装置単独の場合に比べて低減することができる。
また、吸着処理装置と接触酸化装置１３とを併用し、かつ吸着処理装置内の被処理水に投入する吸着剤の量を接触酸化装置１３の生物処理の能力に応じて調整する制御装置２１を設けているので、水温低下による生物処理の能力の低下を吸着処理装置で補うことができる。また、水温上昇によって生物処理の能力が向上した場合は、吸着処理装置における吸着剤の量を減らすことができる。
また、接触酸化装置１３を用いているので、吸着処理装置単独の場合では除去できなかった有機性物質も除去することができる。
このような水処理システムにあっては、良質な処理水を年間を通して安定的に低コストで得ることができる。
【００３３】
また、第１の吸着処理装置１１および第２の吸着処理装置１２を具備し、第２の吸着処理装置１２で使用した吸着剤を第１の吸着処理装置１１に移送する吸着剤移送装置１７を具備しているので、以下の理由から、吸着剤の効率的な使用が可能である。すなわち、吸着剤であるゼオライトは、アンモニウムイオンの濃度が低い方が、吸着剤単位質量あたりのアンモニウムイオンの吸着量が多くなる傾向がある。よって、アンモニウムイオン濃度が比較的低い第２の吸着処理装置１２においてフレッシュな吸着剤を用いた方がアンモニウムイオンの吸着効率がよい。第２の吸着処理装置１２において使用された吸着剤の吸着能は、飽和に達していないので、これを第１の吸着処理装置１１にて再利用することが可能であり、吸着剤をより効率的に使用できる。
【００３４】
また、以上説明した水処理方法にあっては、被処理水中の対象物質を吸着剤に吸着させる吸着処理工程と、吸着処理された被処理水を生物学的に処理する生物処理工程とを併用しているので、吸着処理工程における吸着剤の使用量を吸着処理工程単独の場合に比べて低減することができる。
また、吸着処理工程と生物処理工程とを併用し、かつ吸着処理工程において被処理水に投入する吸着剤の量を、生物処理工程の生物処理の能力に応じて調整しているので、水温低下による生物処理の能力の低下を吸着処理工程で補うことができる。また、水温上昇によって生物処理の能力が向上した場合は、吸着処理工程における吸着剤の量を減らすことができる。
また、生物処理工程を有しているので、吸着処理工程単独の場合では除去できなかった有機性物質も除去することができる。
このような水処理方法にあっては、良質な処理水を年間を通して安定的に低コストで得ることができる。
【００３５】
（形態例２）
なお、本発明における生物処理手段は、上述の接触酸化法による装置（接触酸化装置１３）に限定はされず、標準活性汚泥法、膜分離式活性汚泥法、オキシデーションディチ法（ＯＤ法）などの硝化脱窒法による装置を用いることができる。以下、膜分離式活性汚泥法の装置を用いた例について説明する。
【００３６】
図２は、本発明の水処理システムの他の形態例を示す概略構成図であり、この水処理システムは、図１の水処理システムにおける接触酸化装置１３および加圧浮上分離装置１４の代わりに、浸漬型膜分離装置４０を設けたものである。
浸漬型膜分離装置４０は、被処理水の生物処理および固液分離を行うものであり、膜分離槽４１と、この中に配置された中空糸膜モジュール４２と、これに接続された吸引ポンプ４３と、膜分離槽４１に空気を供給するブロアポンプ４４と、中空糸膜モジュール４２の下方に配置され、ブロアポンプ４４からの空気を膜分離槽４１内に散気する散気管４５とを備えたものである。
中空糸膜モジュール４２は、略平行にシート状に配列された複数本の中空糸膜４６と、この両端部をその開口を維持したまま支持する２本の集水管４７とを備え、集水管４７の端部が吸引ポンプ４３に接続されたものである。
【００３７】
次に、図示例の水処理システムを用いた水処理方法について説明する。
吸着処理工程は、形態例１の水処理システムを用いた場合と同じなので、説明を省略する。
第２の吸着処理装置１２において吸着処理された被処理水は、第２の吸着処理装置１２から溢れ、第２の吸着処理装置１２と浸漬型膜分離装置４０との高低差によって浸漬型膜分離装置４０に供給され、浸漬型膜分離装置４０において生物学的に処理され、固液分離される。具体的には、好気性微生物（汚泥）を含む被処理水にブロアポンプ４４からの空気を散気管４５から散気して、空気の存在下、好気性微生物によって対象物質を酸化、分解する。これと同時に、吸引ポンプ４３を作動させることにより、浸漬型膜分離装置４０の被処理水が中空糸膜４６を介して吸引され、その膜面で微生物や吸着剤等の固形物が捕らえられ、吸引ポンプ４３側から処理水が得られる。
【００３８】
（その他の形態）
本発明の水処理システムは、図示例のものに限定はされず、吸着処理手段と、生物処理手段と、吸着剤投入手段と、生物処理手段における生物処理の能力を検知する能力検知手段と、能力検知手段で検知された生物処理の能力に応じて吸着剤の投入量を調整する投入量調整手段とを具備するものであればよい。
例えば、吸着処理手段は、図示例のように２段のものに限定はされず、１段のものであっても、３段以上のものであっても構わない。吸着処理手段は、被処理水の種類、水処理システムで得られる処理水に含まれる対象物質の目標濃度等に応じてその段数を適宜設計すればよい。
【００３９】
また、能力検知手段は、図示例のような温度センサ２０に限定はされず、能力検知手段として、生物処理手段における処理水のＣＯＤ（化学的酸素要求量）やアンモニア性窒素濃度を測定するセンサ等を用いても構わない。容易に生物処理手段における生物処理の能力を検知することができることから、能力検知手段としては、温度センサが好適である。
また、第１の吸着処理装置１１から第２の吸着処理装置１２への被処理水の送液、および第２の吸着処理装置１２から接触酸化装置１３または浸漬型膜分離装置４０への被処理水の送液は、図示例では、各装置の高低差を利用した重力式で送液しているが、各装置間に送液ポンプを設けて、これで被処理水を送液しても構わない。
【００４０】
また、浸漬型膜分離装置４０においては、吸引ポンプ４３によって被処理水を中空糸膜４６を介して吸引し、処理水と固形分とを分離しているが、吸引ポンプ４３の代わりに、浸漬型膜分離装置４０よりも下方に貯水槽を設け、重力やサイフォン効果を利用して被処理水を中空糸膜４６を介して吸引し、この貯水槽に処理水を送液するようにしてもよい。吸引ポンプ４３を使用しないことによって、より低コストで処理水を得ることができる。
【００４１】
また、膜分離装置を用いる場合、これに用いる分離膜としては、中空糸膜以外に、平膜、管状膜、セラミック膜、金属膜等の各種分離膜を用いることができる。分離膜の材質も、固液分離が可能なものであればよく、高分子、金属、セラミックなどから選ぶことができる。
分離膜の平均孔径は、分離膜の二次側への吸着剤の流入を防ぐために、吸着剤の平均粒径よりも小さいことが好ましく、具体的には、０．０１〜５μｍが好ましく、０．１〜１．０μｍがより好ましい。また、中空糸膜の平均孔径を０．２μｍ以下とすると、被処理水中の微生物類をほぼ完全に膜面で捕らえることができる。
【００４２】
また、本発明の水処理方法においては、吸着処理工程の被処理水に投入する吸着剤の量を、制御装置２１で自動調整する代わりに、作業者によって調整してもよい。
例えば、生物処理工程における被処理水の水温が１５℃以下となった場合、生物活性の低下に伴う生物処理の能力の低下が顕著となるので、吸着処理工程の被処理水に投入する吸着剤の投入量を、２０℃における投入量に対して増やす。この時の投入量は、２０℃における投入量に対して５質量％以上１００質量％以下増やすことが好ましい。投入量の増加割合が５質量％未満では、生物処理工程における生物処理の能力の低下を補うことができず、投入量の増加割合が１００質量％を超えると、吸着剤のコストが増加するだけではなく、被処理水の粘度が高くなり、送液ポンプ等への負荷が増加し、メンテナンスのコストも増加する。
【００４３】
一方、生物処理工程における被処理水の水温が２５℃以上となった場合、生物活性の上昇に伴って生物処理の能力が上がるので、吸着処理工程の被処理水に投入する吸着剤の投入量を、２０℃における投入量に対して減らすことができる。この時の投入量は、２０℃における投入量に対して５質量％以上減らすことが好ましい。投入量の削減割合が５質量％未満では、生物活性の上昇のメリットを吸収剤のコスト削減という形で十分に享受できない。
【００４４】
【実施例】
以下、具体的な実施例について説明する。
［実施例１］
図２に示す水処理システムを用いて、アンモニウムイオンを含む被処理水を処理した。第１の吸着処理槽２３および第２の吸着処理槽２５としては、容積が３Ｌのものを用い、膜分離槽４１としては、容積が６Ｌのものを用いた。
吸着剤としては、アンモニウムイオンを吸着する作用を持つゼオライト（平均粒径４．０μｍ）を用い、吸着剤を凝集させる凝集剤としては、ＰＦＣ（ポリ塩化鉄）を用いた。
【００４５】
水処理システムの運転条件は以下の通りである。
（１）被処理水中のアンモニウムイオン濃度：１００ｍｇ／Ｌ
（２）被処理水中のリン濃度：１０ｍｇ／Ｌ
（３）被処理水中の細菌：１．２×１０^６ＣＦＵ／ｍＬ
（４）被処理水の濁度：３
（５）被処理水の水温：２０℃
（６）被処理水の第１の吸着処理装置１１への供給速度：２Ｌ／ｈｒ
（７）第１の吸着処理装置１１および第２の吸着処理装置１２における被処理水の滞留時間：各１．５時間
（８）第１の吸着処理装置１１および第２の吸着処理装置１２におけるゼオライト濃度：各３０００ｍｇ／Ｌ
（９）吸着剤移送装置１７によるゼオライト移送速度：１８ｇ／ｈｒ
（１０）第１の吸着処理装置１１からの使用済みゼオライト回収速度：１８ｇ／ｈｒ
（１１）第２の吸着処理装置１２へのフレッシュなゼオライトの投入速度：１８ｇ／ｈｒ
（１２）第２の吸着処理装置１２へのＰＦＣ（ポリ塩化鉄）の投入は、被処理水中のＰＦＣ濃度が１０ｐｐｍとなるように連続的に行った。
（１３）浸漬型膜分離装置４０における被処理水の滞留時間：３時間
（１４）中空糸膜の分画特性：０．１μｍ
【００４６】
以上の条件で、水処理システムを定常運転し、処理水を得た。処理水のアンモニウム濃度は８．５ｍｇ／Ｌ、リン濃度は０．８ｍｇ／Ｌであった。また、処理水から細菌は全く検出されなかった。また、処理水の濁度は１であった。このように、図２に示す水処理システムによって、良質な処理水を得ることができた。
【００４７】
［実施例２］
被処理水の水温を３０℃に変更して実施例１と同様に被処理水を処理した。ゼオライトの投入速度、ゼオライト移送速度およびゼオライト回収速度を、被処理水の水温が２０℃の時よりも１０％減らした。
（５）被処理水の水温：３０℃
（８）第１の吸着処理装置１１および第２の吸着処理装置１２におけるゼオライト濃度：各２７００ｍｇ／Ｌ
（９）吸着剤移送装置１７によるゼオライト移送速度：１６．２ｇ／ｈｒ
（１０）第１の吸着処理装置１１からの使用済みゼオライト回収速度：１６．２ｇ／ｈｒ
（１１）第２の吸着処理装置１２へのフレッシュなゼオライトの投入速度：１６．２ｇ／ｈｒ
【００４８】
以上の条件で、水処理システムを定常運転し、処理水を得た。処理水のアンモニウム濃度は９．２ｍｇ／Ｌ、リン濃度は０．６ｍｇ／Ｌであった。また、処理水から細菌は全く検出されなかった。また、処理水の濁度は１であった。このように、被処理水の水温が２０℃の時とほぼ変わらない水質の処理水を得ることができた。
【００４９】
［実施例３］
被処理水の水温を１３℃に変更して実施例１と同様に被処理水を処理した。ゼオライトの投入速度、ゼオライト移送速度およびゼオライト回収速度を、被処理水の水温が２０℃の時よりも２０％増やした。
（５）被処理水の水温：１３℃
（８）第１の吸着処理装置１１および第２の吸着処理装置１２におけるゼオライト濃度：各３６００ｍｇ／Ｌ
（９）吸着剤移送装置１７によるゼオライト移送速度：２１．６ｇ／ｈｒ
（１０）第１の吸着処理装置１１からの使用済みゼオライト回収速度：２１．６ｇ／ｈｒ
（１１）第２の吸着処理装置１２へのフレッシュなゼオライトの投入速度：２１．６ｇ／ｈｒ
【００５０】
以上の条件で、水処理システムを定常運転し、処理水を得た。処理水のアンモニウム濃度は８．５ｍｇ／Ｌ、リン濃度は０．８ｍｇ／Ｌであった。また、処理水から細菌は全く検出されなかった。また、処理水の濁度は１であった。このように、被処理水の水温が２０℃の時とほぼ変わらない水質の処理水を得ることができた。
【００５１】
［実施例４］
水処理システムを図１に示すものに変更した以外は、実施例２と同様に被処理水を処理した。接触酸化槽２７としては、容積が６Ｌのものを用いた。ゼオライトの投入速度、ゼオライト移送速度およびゼオライト回収速度を、被処理水の水温が２０℃の時よりも１５％減らした。
（５）被処理水の水温：３０℃
（８）第１の吸着処理装置１１および第２の吸着処理装置１２におけるゼオライト濃度：各２５５０ｍｇ／Ｌ
（９）吸着剤移送装置１７によるゼオライト移送速度：１５．３ｇ／ｈｒ
（１０）第１の吸着処理装置１１からの使用済みゼオライト回収速度：１５．３ｇ／ｈｒ
（１１）第２の吸着処理装置１２へのフレッシュなゼオライトの投入速度：１５．３ｇ／ｈｒ
以上の条件で、水処理システムを定常運転し、処理水を得た。処理水のアンモニウム濃度は１０．５ｍｇ／Ｌ、リン濃度は０．８ｍｇ／Ｌであった。
【００５２】
［実施例５］
水処理システムを図１に示すものに変更した以外は、実施例３と同様に被処理水を処理した。ゼオライトの投入速度、ゼオライト移送速度およびゼオライト回収速度を、被処理水の水温が２０℃の時よりも２０％増やした。
（５）被処理水の水温：１３℃
（８）第１の吸着処理装置１１および第２の吸着処理装置１２におけるゼオライト濃度：各３６００ｍｇ／Ｌ
（９）吸着剤移送装置１７によるゼオライト移送速度：２１．６ｇ／ｈｒ
（１０）第１の吸着処理装置１１からの使用済みゼオライト回収速度：２１．６ｇ／ｈｒ
（１１）第２の吸着処理装置１２へのフレッシュなゼオライトの投入速度：２１．６ｇ／ｈｒ
以上の条件で、水処理システムを定常運転し、処理水を得た。処理水のアンモニウム濃度は１０．０ｍｇ／Ｌ、リン濃度は０．９ｍｇ／Ｌであった。
【００５３】
［比較例１］
被処理水の水温を１３℃に変更して実施例１と同様に被処理水を処理した。ただし、ゼオライトの投入速度、ゼオライト移送速度およびゼオライト回収速度を、被処理水の水温が２０℃の時と同じにした。
以上の条件で、水処理システムを定常運転し、処理水を得た。処理水のアンモニウム濃度は２８．５ｍｇ／Ｌ、リン濃度は３．８ｍｇ／Ｌであり、処理能力が低下した。
【００５４】
【発明の効果】
以上説明したように、本発明の水処理システムは、被処理水中の対象物質を吸着剤に吸着させる吸着処理手段と、吸着処理手段で処理された被処理水を生物学的に処理する生物処理手段と、吸着処理手段の被処理水に吸着剤を投入する吸着剤投入手段と、生物処理手段における生物処理の能力を検知する能力検知手段と、能力検知手段で検知された生物処理の能力に応じて吸着剤の投入量を調整する投入量調整手段とを具備するものであるので、水温によって処理能力が大きく変動することなく、低コストで被処理水中の対象物質を除去できる。
【００５５】
また、本発明の水処理システムが、前記吸着処理手段を２段以上具備し、さらに、後段側の吸着処理手段で使用した吸着剤を前段側の吸着処理手段に移送する吸着剤移送手段を具備するものであれば、吸着剤の効率的な使用が可能となる。
また、前記能力検知手段が、温度センサであれば、容易に生物処理手段における生物処理の能力を検知することができる。
【００５６】
また、本発明の水処理方法は、被処理水中の対象物質を吸着剤に吸着させる吸着処理工程と、吸着処理工程で処理された被処理水を生物学的に処理する生物処理工程とを有し、吸着処理工程の被処理水に投入する吸着剤の量を、生物処理工程における生物処理の能力に応じて調整する方法であるので、水温によって処理能力が大きく変動することなく、低コストで被処理水中の対象物質を除去できる。
【００５７】
また、本発明の水処理方法が、前記吸着処理工程を２工程以上有し、後工程側の吸着処理工程で使用した吸着剤を前工程側の吸着処理工程で再使用する方法であれば、吸着剤の効率的な使用が可能となる。
また、前記生物処理の能力を、生物処理工程における被処理水の温度から見積るようにすれば、容易に生物処理工程における生物処理の能力を検知することができる。
【図面の簡単な説明】
【図１】本発明の水処理システムの一例を示す概略構成図である。
【図２】本発明の水処理システムの他の例を示す概略構成図である。
【符号の説明】
１１第１の吸着処理装置（吸着処理手段）
１２第２の吸着処理装置（吸着処理手段）
１３接触酸化装置（生物処理手段）
１５吸着剤投入装置（吸着剤投入手段）
１７吸着剤移送装置（吸着剤移送手段）
２０温度センサ（能力検知手段）
２１制御装置（投入量調整手段）
４０浸漬型膜分離装置（生物処理手段）[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a water treatment system and a water treatment method, and more particularly, to a water treatment system and a water treatment for treating wastewater containing a high concentration of nitrogen and phosphorus discharged from food factories, alcohol factories, livestock facilities, and the like. About the method.
[0002]
[Prior art]
Ammonia nitrogen (NH) contained in wastewater₄ -N) can be removed by (i) an air stripping method in which the wastewater is made alkaline with a pH of 10 or more and a waterfall occurs, and ammonia nitrogen is released as ammonia gas, and (ii) ammonia nitrogen is oxidized by chlorine gas. Injection method of oxidizing nitrogen into nitrogen gas, (iii) ion exchange adsorption method of adsorbing ammoniacal nitrogen to an inorganic ion exchanger, (iv) NH3 by nitrifying bacteria and nitrifying bacteria₄ ⁺NO₂ ⁻, NO₃ ⁻A biological nitrification and denitrification method, which oxidizes (nitrifies) nitrogen to nitrogen gas by a denitrifying bacterium, has been proposed.
[0003]
However, among the above-described methods for removing ammoniacal nitrogen, (i) the air stripping method and (ii) the chlorine injection method have a problem that the amount of chemicals used is large and the treatment cost is high. Further, (ii) the chlorine injection method also had a problem of residual chlorine in the treated water.
[0004]
(Iii) The ion exchange adsorption method has been recently developed due to the short processing time, and several methods have been disclosed which focus on the selective adsorption of ammoniacal nitrogen by zeolite.
JP-A-6-269776 discloses a method of adsorbing ammoniacal nitrogen in wastewater to zeolite in an adsorption treatment tank. However, this method has a problem that the processing capacity is insufficient because the ammonia adsorption capacity of zeolite itself is very small.
[0005]
JP-A-11-239785 discloses a method using a substituted zeolite in which sodium ions and potassium ions of zeolite are partially substituted with magnesium ions. According to this method, if the concentration of ammonium ions in the wastewater is 30 mg / L or less, stable treatment can be performed. However, when the ammonium ion concentration exceeds 30 mg / L, especially 1000 mg / L or more, the adsorption equilibrium is reached in a state where the amount of ammonium ion adsorbed per unit mass of the substituted zeolite is small, so that the adsorption capacity originally possessed by the substituted zeolite Cannot be used efficiently, the amount of substituted zeolite to be charged increases, and the processing cost increases.
[0006]
On the other hand, (iv) biological nitrification denitrification is widely used because of its low processing cost. However, in this method, when the water temperature of the wastewater falls to 15 ° C. or lower, the biological activity decreases and the treatment capacity decreases, so that it was necessary to extend the treatment time. As described above, (iv) the biological nitrification and denitrification method has a problem that stable processing is difficult because its processing ability depends on temperature.
[0007]
[Patent Document 1]
JP-A-6-269776 (pages 2-5)
[Patent Document 2]
JP-A-11-239785 (pages 2-6)
[0008]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to provide a water treatment system and a water treatment method that can remove a target substance in water to be treated at low cost without a great change in treatment capacity depending on the water temperature.
[0009]
[Means for Solving the Problems]
That is, the water treatment system of the present invention comprises: an adsorption treatment means for adsorbing a target substance in the treatment water to an adsorbent; a biological treatment means for biologically treating the treatment water treated by the adsorption treatment means; Adsorbent charging means for charging the adsorbent into the water to be treated by the processing means, capacity detecting means for detecting the biological processing capacity of the biological processing means, and adsorbent in accordance with the biological processing capacity detected by the capacity detecting means And a charging amount adjusting means for adjusting the charging amount.
[0010]
Further, the water treatment system of the present invention is provided with two or more stages of the adsorption treatment means, and further with an adsorbent transfer means for transferring the adsorbent used in the latter adsorption treatment means to the former adsorption treatment means. It is desirable that
Further, in the water treatment system of the present invention, it is preferable that the capacity detecting means is a temperature sensor.
[0011]
Further, the water treatment method of the present invention has an adsorption treatment step of adsorbing a target substance in the treatment water to an adsorbent, and a biological treatment step of biologically treating the treatment water treated in the adsorption treatment step. The amount of the adsorbent to be added to the water to be treated in the adsorption treatment step is adjusted according to the biological treatment capacity in the biological treatment step.
[0012]
Further, the water treatment method of the present invention preferably has two or more adsorption treatment steps, and the adsorbent used in the subsequent adsorption treatment step is preferably reused in the preceding adsorption treatment step.
Further, in the water treatment method of the present invention, it is desirable to estimate the capacity of the biological treatment from the temperature of the water to be treated in the biological treatment step.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
(Form example 1)
FIG. 1 is a schematic configuration diagram showing one embodiment of the water treatment system of the present invention. This water treatment system comprises an adjustment tank 10 for adjusting the amount of inflow water, pH and the like of the water to be treated, a first adsorption treatment device 11 and a second adsorption treatment device 12 for adsorbing a target substance in the treatment water to an adsorbent. (Adsorption treatment means), a contact oxidation device 13 (biological treatment means) for biologically treating the water to be treated treated by the adsorption treatment device, and solid-liquid separation of the treatment water treated by the contact oxidation device 13 Pressurized flotation device 14, an adsorbent input device 15 (adsorbent input means) for inputting an adsorbent into the water to be treated of the second adsorption processing device 12, and a treatment target of the second adsorption treatment device 12. A flocculant feeding device 16 for feeding a flocculant into water, an adsorbent transfer device 17 (adsorbent transfer means) for transferring the adsorbent used in the second adsorption treatment device 12 to the first adsorption treatment device 11, The adsorbent used in the first adsorption processing device 11 is collected. An adsorbent recovery device 18; an adsorbent dehydration device 19 for dehydrating the adsorbent recovered by the adsorbent recovery device 18; and a temperature sensor 20 (capacity detecting means) for measuring the temperature of the water to be treated in the contact oxidation device 13. And the amount of adsorbent input from the adsorbent input device 15, the amount of adsorbent transferred by the adsorbent transfer device 17, and the amount of adsorbent recovered by the adsorbent recovery device 18 according to the water temperature measured by the temperature sensor 20. And a control unit 21 (feed amount adjusting means) for adjusting the amount of water to be treated, and a treated water supply device 22 for feeding treated water from the regulating tank 10 to the first adsorption treatment device 11. It is.
[0014]
The first adsorption treatment apparatus 11 includes an adsorption treatment tank 23 having a portion for bringing the water to be treated into contact with the adsorbent and a portion for causing the adsorbent to settle and separate, and a stirring device for stirring the water to be treated in the adsorption treatment tank 23. And a device 24.
Similarly, the second adsorption treatment device 12 includes an adsorption treatment tank 25 and a stirring device 26, and the water to be treated treated by the first adsorption treatment device 11 is subjected to the second adsorption treatment by gravity. It is installed at a position lower than the first adsorption processing apparatus 11 so as to flow to the processing apparatus 12.
[0015]
The contact oxidation device 13 includes a contact oxidation tank 27, a contact member 28 disposed therein to adhere aerobic microorganisms (sludge), a blower pump 29 for supplying air to the contact oxidation tank 27, and a contact member 28. A diffuser 30 is provided below and diffuses air from the blower pump 29 into the contact oxidation tank 27.
The pressure flotation / separation device 14 floats the sludge in the water to be treated by fine bubbles generated in the water to be treated by pressurization, and separates the water to be treated into sludge and treated water. A tank 31, a pressurizing means (not shown) such as a pressurizing tank and a pressurizing pump for pressurizing the water to be treated in the solid-liquid separation tank 31, a scraping means 32 for scraping the floating sludge, a scraper or the like It is provided with.
[0016]
The adsorbent charging device 15 is for charging the adsorbent to the last adsorption treatment device among the plurality of adsorption treatment devices, and includes a storage container (not shown) for storing the adsorbent and a second adsorption treatment device. It has a charging port (not shown) for charging into the processing apparatus 12 and an adjusting mechanism (not shown) for adjusting the charging speed (charging amount per time) of the adsorbent provided at the charging port. is there.
Similarly, the coagulant charging device 16 is for charging the coagulant into the last adsorption device among the plurality of adsorption devices, and stores a coagulant (not shown) for storing the coagulant and a coagulant. And an adjusting mechanism (not shown) provided at the inlet for adjusting the feeding speed (amount per hour) of the flocculant. It is a thing.
[0017]
The adsorbent transfer device 17 collects the adsorbent 33 coagulated and settled by the coagulant at the bottom of the adsorption treatment tank 25 of the second adsorption treatment device 12 together with some water to be treated. To supply. As the adsorbent transfer device 17, for example, a screw pump, a snake pump, a gear pump, a cascade pump, a tube pump, or the like can be appropriately selected and used according to the viscosity, concentration, amount, and the like of the adsorbent 33.
The adsorbent recovery device 18 collects the adsorbent 34 settled at the bottom of the adsorption treatment tank 23 of the first adsorption treatment device 11 together with a small amount of water to be treated, and transfers it to the adsorbent dehydration device 19. As the adsorbent recovery device 18, for example, a screw pump, a snake pump, a gear pump, a cascade pump, a tube pump, or the like can be appropriately selected and used according to the viscosity, concentration, amount, and the like of the adsorbent 34.
[0018]
The adsorbent dehydrating device 19 dehydrates water from the adsorbent recovered from the first adsorption treatment device 11, returns the wastewater from the dehydration to the adjusting tank 10, and obtains the dehydrated adsorbent. As the adsorbent dehydrator 19, a roll dehydrator, a pressure dehydrator, a vacuum dehydrator, or the like can be used.
The temperature sensor 20 measures the temperature of the water to be treated in the catalytic oxidizer 13, which is one of the measures of the biological treatment capacity of the catalytic oxidizer 13.
The to-be-treated water supply device 22 is a liquid feed pump that sends the to-be-treated water from the adjustment tank 10 to the first adsorption treatment device 11. Examples of the to-be-treated water supply device 22 include a magnet pump, a spiral pump, and a diaphragm. A pump, a submersible pump, a screw pump, a snake pump, a gear pump, a cascade pump, a tube pump, or the like can be used.
[0019]
The control device 21 includes a processing unit (not shown) and an interface unit (not shown), and is schematically configured. The control unit 21 receives the adsorbent from the adsorbent input device 15 according to the water temperature measured by the temperature sensor 20. It adjusts the input amount, the amount of adsorbent transferred by the adsorbent transfer device 17, the amount of adsorbent recovered by the adsorbent recovery device 18, and the like.
[0020]
The processing unit estimates the processing capacity of the catalytic oxidizer 13 from the temperature information from the temperature sensor 20 and the water temperature-processing capacity relational expression based on the measurement result of the processing capacity of the catalytic oxidizer 13 at each water temperature of the water to be treated. Then, the amount of adsorbent supplied from the adsorbent input device 15 (input speed), the amount of adsorbent transferred by the adsorbent transfer device 17 (transfer speed), the amount of adsorbent recovered by the adsorbent recovery device 18 (recovery speed) ) Is determined and adjusted.
The interface unit electrically connects the adsorbent input device 15, the adsorbent transfer device 17, the adsorbent recovery device 18, the temperature sensor 20, and the like to the processing unit.
[0021]
Note that this processing unit may be realized by dedicated hardware, and this processing unit includes a memory and a central processing unit (CPU), and stores a program for realizing the function of the processing unit. The function may be realized by loading it into a memory and executing it.
In addition, an input device, a display device, and the like are connected to the control device 21 as peripheral devices. Here, the input device refers to an input device such as a display touch panel, a switch panel, and a keyboard, and the display device refers to a CRT or a liquid crystal display device.
[0022]
Next, a water treatment method using the water treatment system of the illustrated example will be described.
At the start of the operation of the water treatment system, first, the adsorbent from the adsorbent charging device 15 and the flocculant from the flocculant charging device 16 are respectively supplied to the second adsorption processing device 12. A predetermined amount. Then, the water to be treated, whose flow rate, pH, etc. has been adjusted in the adjusting tank 10, is supplied to the first adsorption treatment apparatus 11 by the treatment water supply device 22, and the treatment water overflowing from the first adsorption treatment apparatus 11 is supplied. Water is supplied to the second adsorption processing device 12 using the height difference between the first adsorption processing device 11 and the second adsorption processing device 12.
[0023]
Next, the agitation device 26 provided in the second adsorption treatment device 12 is operated to bring the water to be treated into contact with the adsorbent in the second adsorption treatment device 12, and the target substance in the water to be treated is adsorbed. To be absorbed. After performing the adsorption treatment for a predetermined time in the second adsorption treatment device 12, the adsorbent transfer device 17 was operated, and the coagulation agent settled and settled on the bottom of the adsorption treatment tank 25 of the second adsorption treatment device 12. The adsorbent 33 is recovered together with a small amount of water to be treated, a predetermined amount of the adsorbent is supplied to the first adsorption treatment device 11, and the stirring device 24 provided in the first adsorption treatment device 11 is operated to The treated water is brought into contact with the adsorbent in the first adsorption treatment device 11, and the target substance in the water to be treated is adsorbed by the adsorbent.
[0024]
After performing the adsorption treatment in the first adsorption treatment device 11 for a predetermined time, the water to be treated in the adjustment tank 10 is continuously supplied to the first adsorption treatment device 11 by the treatment water supply device 22 at a predetermined supply speed. And start continuous operation. In the continuous operation, the adsorbent is supplied from the adsorbent input device 15 and the coagulant is supplied from the coagulant input device 16 into the adsorption processing device 12 continuously at a predetermined input speed. The adsorbent is collected from the treatment device 12 by the adsorbent transfer device 17, and the collected adsorbent is supplied to the first adsorption treatment device 11 at a predetermined transfer speed. In addition, the adsorbent is recovered from the first adsorption processing device 11 by the adsorbent recovery device 18 at a predetermined recovery speed. Here, the recovery of the adsorbent from the adsorption treatment apparatus is preferably performed intermittently in order to minimize the amount of water to be treated mixed. The adsorbent recovered from the first adsorption treatment device 11 is dehydrated by the adsorbent dehydrator 19, and the wastewater is returned to the adjusting tank 10 to obtain a dehydrated adsorbent. The desorbed sorbent is reused or discarded.
[0025]
During continuous operation, the water to be treated continuously supplied from the regulating tank 10 to the first adsorption treatment device 11 by the treatment water supply device 22 first contacts the adsorbent in the first adsorption treatment device 11. Then, the target substance in the water to be treated is adsorbed by the adsorbent. The water to be subjected to the adsorption treatment overflows from the first adsorption treatment device 11 and is supplied to the second adsorption treatment device 12 by a height difference between the first adsorption treatment device 11 and the second adsorption treatment device 12, In the second adsorption processing device 12, the target substance in the water to be treated is adsorbed by the adsorbent by coming into contact with the adsorbent.
[0026]
The water to be treated, which has been subjected to the adsorption treatment in the second adsorption treatment device 12, overflows from the second adsorption treatment device 12, and is supplied to the contact oxidation device 13 by the height difference between the second adsorption treatment device 12 and the contact oxidation device 13. And biologically treated in the catalytic oxidizer 13. Specifically, air from the blower pump 29 is diffused from the air diffuser 30 to the contact material 28 to which the aerobic microorganisms (sludge) adhere, and the target material is oxidized and decomposed by the aerobic microorganisms in the presence of air. The water to be oxidized in the contact oxidizing device 13 is supplied to the pressurized flotation device 14, where it is separated into sludge and treated water.
[0027]
As the adsorbent, when the target substance is a nitrogen compound such as ammoniacal nitrogen, a pigment, an odorant, or the like, synthetic zeolite, natural zeolite, artificial zeolite, or the like can be used. Further, when the target substance is a phosphorus compound, an inorganic coagulant, titanium oxide, activated alumina, titanium silicate, or the like can be used.
Since the surface area increases as the particle size of the adsorbent decreases, the adsorbent preferably has an average particle size of 0.01 to 50 μm. When solid-liquid separation is performed using a membrane separation device described below, the range of 0.2 to 10 μm is preferable from the range of the pore size of the membrane (the balance between the permeation flow rate of the membrane and the inhibition of bacteria). When the solid-liquid separation is carried out by gentle sedimentation, the range of 1 to 20 μm is preferable in terms of sedimentation and swirling by stirring.
[0028]
The input amount (input speed) of the adsorbent is determined by the adsorbent adsorption capacity, the target concentration of the target substance contained in the water to be treated after the adsorption treatment, the target concentration of the target substance contained in the treated water obtained by the water treatment system, It is appropriately determined according to the processing capacity of the biological treatment means.
The present invention is characterized in that the input amount (input speed) of the adsorbent is adjusted particularly according to the processing capacity of the biological processing means. Specifically, in the control device 21, the temperature of the contact oxidizing device is calculated from the temperature information from the temperature sensor 20 and the water temperature-processing capability relational expression based on the measurement result of the processing capability of the contact oxidizing device 13 at each water temperature of the water to be treated. The processing capacity of the adsorbent 13 is estimated, and the controller 21 controls the adsorbent input amount (input speed) from the adsorbent input device 15, the adsorbent transfer amount (transfer speed) by the adsorbent transfer device 17, and the adsorbent recovery. The amount (recovery speed) of the adsorbent recovered by the device 18 is determined and adjusted.
[0029]
For example, when the temperature of the water to be treated is 20 ° C., the amount of the adsorbent (input speed) for achieving the target removal rate (target water quality) of the target substance by the adsorption treatment and the biological treatment is initially input at the start of operation. Set as an amount. When the water temperature falls below 20 ° C. during the continuous operation, the input amount (input speed) of the adsorbent is increased in accordance with the degree of reduction in the treatment capacity of the catalytic oxidizer 13 due to the decrease in biological activity, and The amount of the adsorbent is increased with respect to the amount of adsorption treatment per hour (the supply speed of the water to be treated from the adjustment tank 10). On the other hand, when the water temperature rises above 20 ° C., the input amount (input speed) of the adsorbent is reduced in accordance with the degree of increase in the processing capacity of the catalytic oxidation device 13 accompanying the increase in biological activity, and The amount of the adsorbent with respect to the adsorption treatment amount (the supply speed of the water to be treated from the adjustment tank 10) is reduced. The amount of adsorbent transferred by the adsorbent transfer device 17 (transfer speed) and the recovery of the adsorbent by the adsorbent recovery device 18 are adjusted in accordance with the change in the amount (input speed) of the adsorbent from the adsorbent input device 15. Of course, it is necessary to adjust the amount (recovery speed).
[0030]
As a flocculant for flocculating the adsorbent, an inorganic flocculant, an organic polymer flocculant, and a flocculant can be used. Among them, an iron-based inorganic coagulant is preferable because it can reduce used zeolite to soil and does not generate waste.
In the case of an inorganic flocculant, the amount of the flocculant to be charged (feeding rate) is determined based on the sedimentation of zeolite as an adsorbent, the concentration of phosphorus in the water to be treated, the target concentration of phosphorus contained in the treated water obtained by the water treatment system, and the like. What is necessary is just to determine suitably according to conditions.
The organic polymer coagulant is preferably used in combination with the inorganic coagulant, and the amount of the organic coagulant may be appropriately determined as in the case of the inorganic coagulant.
[0031]
The residence time of the water to be treated in the first adsorption treatment device 11 and the second adsorption treatment device 12 may be appropriately determined according to conditions such as the concentration of the target substance in the treatment water, the type and amount of the adsorbent, and the like. Good. This residence time can be adjusted by adjusting the supply speed of the water to be treated to the first adsorption treatment device 11 by the water supply device 22.
Further, the residence time of the water to be treated in the contact oxidation device 13 may be appropriately determined according to conditions such as the concentration of the target substance in the water to be treated and the volume of the contact oxidation tank 27.
[0032]
In the water treatment system described above, the adsorption treatment device for adsorbing the target substance in the water to be treated to the adsorbent and the contact oxidizing device 13 for biologically treating the water subjected to the adsorption treatment are used in combination. Therefore, the amount of the adsorbent used in the adsorption processing apparatus can be reduced as compared with the case where the adsorption processing apparatus is used alone.
Further, a control device 21 that uses both the adsorption treatment device and the contact oxidation device 13 and adjusts the amount of the adsorbent to be introduced into the water to be treated in the adsorption treatment device according to the biological treatment capability of the contact oxidation device 13 is provided. Since it is provided, it is possible to compensate for the decrease in the biological treatment ability due to the decrease in water temperature by the adsorption treatment device. Further, when the ability of biological treatment is improved due to a rise in water temperature, the amount of adsorbent in the adsorption treatment device can be reduced.
Further, since the contact oxidation device 13 is used, organic substances that could not be removed by the adsorption treatment device alone can also be removed.
In such a water treatment system, high quality treated water can be stably obtained at low cost throughout the year.
[0033]
In addition, a first adsorption processing device 11 and a second adsorption processing device 12 are provided, and an adsorbent transfer device 17 for transferring the adsorbent used in the second adsorption processing device 12 to the first adsorption processing device 11 is provided. As a result, the adsorbent can be used efficiently for the following reasons. That is, in the zeolite that is the adsorbent, the lower the concentration of ammonium ions, the more the amount of ammonium ions adsorbed per unit mass of the adsorbent tends to increase. Therefore, the efficiency of ammonium ion adsorption is better when a fresh adsorbent is used in the second adsorption treatment device 12 having a relatively low ammonium ion concentration. Since the adsorption capacity of the adsorbent used in the second adsorption treatment device 12 has not reached saturation, it can be reused in the first adsorption treatment device 11 and the adsorbent can be used more efficiently. Can be used
[0034]
Further, in the water treatment method described above, the adsorption treatment step of adsorbing the target substance in the water to be treated to the adsorbent and the biological treatment step of biologically treating the water subjected to the adsorption treatment are used in combination. Therefore, the amount of the adsorbent used in the adsorption process can be reduced as compared with the case where the adsorption process is used alone.
In addition, since the adsorption treatment step and the biological treatment step are used together, and the amount of the adsorbent to be added to the water to be treated in the adsorption treatment step is adjusted according to the biological treatment capacity of the biological treatment step, the water temperature decreases. The decrease in the biological treatment ability due to the above can be compensated for by the adsorption treatment step. In addition, when the biological treatment ability is improved due to a rise in water temperature, the amount of the adsorbent in the adsorption treatment step can be reduced.
In addition, since it has a biological treatment step, it is possible to remove organic substances that could not be removed by the adsorption treatment step alone.
In such a water treatment method, high-quality treated water can be stably obtained at low cost throughout the year.
[0035]
(Form example 2)
In addition, the biological treatment means in the present invention is not limited to the above-described apparatus using the catalytic oxidation method (the catalytic oxidation apparatus 13), but includes a standard activated sludge method, a membrane separation activated sludge method, and an oxidation ditch method (OD method). For example, an apparatus based on the nitrification denitrification method can be used. Hereinafter, an example using an apparatus of a membrane separation type activated sludge method will be described.
[0036]
FIG. 2 is a schematic configuration diagram showing another embodiment of the water treatment system of the present invention. The water treatment system is different from the contact oxidation device 13 and the pressure flotation device 14 in the water treatment system of FIG. , An immersion type membrane separation device 40 is provided.
The immersion type membrane separation device 40 performs biological treatment and solid-liquid separation of the water to be treated, and includes a membrane separation tank 41, a hollow fiber membrane module 42 disposed therein, and a suction pump connected thereto. 43, a blower pump 44 for supplying air to the membrane separation tank 41, and an air diffuser 45 disposed below the hollow fiber membrane module 42 and for diffusing air from the blower pump 44 into the membrane separation tank 41. It is.
The hollow fiber membrane module 42 includes a plurality of hollow fiber membranes 46 arranged in a substantially parallel sheet shape, and two water collecting pipes 47 supporting both ends of the hollow fiber membranes while maintaining their openings. Is connected to the suction pump 43.
[0037]
Next, a water treatment method using the water treatment system of the illustrated example will be described.
The adsorption process is the same as the case where the water treatment system of the first embodiment is used, and the description is omitted.
The water to be treated, which has been subjected to the adsorption treatment in the second adsorption treatment device 12, overflows from the second adsorption treatment device 12, and is immersed in the immersion type membrane separation device due to the height difference between the second adsorption treatment device 12 and the immersion type membrane separation device 40. The liquid is supplied to the apparatus 40, biologically treated in the immersion type membrane separation apparatus 40, and subjected to solid-liquid separation. Specifically, air from the blower pump 44 is diffused through the air diffuser 45 into the water to be treated containing aerobic microorganisms (sludge), and the target substance is oxidized and decomposed by the aerobic microorganisms in the presence of air. At the same time, by operating the suction pump 43, the water to be treated in the immersion type membrane separation device 40 is sucked through the hollow fiber membrane 46, and solid substances such as microorganisms and adsorbents are captured on the membrane surface, Treated water is obtained from the suction pump 43 side.
[0038]
(Other forms)
The water treatment system of the present invention is not limited to the example shown in the drawings, and the adsorption treatment means, the biological treatment means, the adsorbent charging means, and the ability detection means for detecting the biological treatment ability in the biological treatment means, What is necessary is just to be provided with the input amount adjustment means which adjusts the input amount of an adsorbent according to the biological treatment capacity detected by the capacity detection means.
For example, the adsorption processing means is not limited to two-stage as shown in the illustrated example, but may be one-stage or three-stage or more. The number of stages of the adsorption treatment means may be appropriately designed according to the type of the water to be treated, the target concentration of the target substance contained in the treated water obtained by the water treatment system, and the like.
[0039]
Further, the capacity detecting means is not limited to the temperature sensor 20 as shown in the illustrated example. As the capacity detecting means, a sensor for measuring COD (chemical oxygen demand) of treated water and ammonia nitrogen concentration in the biological treatment means is used. Etc. may be used. Since the ability of biological treatment in the biological treatment means can be easily detected, a temperature sensor is suitable as the ability detection means.
In addition, the supply of the water to be treated from the first adsorption treatment device 11 to the second adsorption treatment device 12 and the treatment of the treatment water from the second adsorption treatment device 12 to the contact oxidation device 13 or the immersion type membrane separation device 40. In the illustrated example, water is supplied by gravity using the height difference of each device.However, even if a liquid supply pump is provided between each device and the water to be treated is supplied by this, I do not care.
[0040]
Further, in the immersion type membrane separation device 40, the water to be treated is sucked by the suction pump 43 through the hollow fiber membrane 46 to separate the treated water and the solid content. A water storage tank is provided below the mold membrane separation device 40, and the water to be treated is sucked through the hollow fiber membrane 46 by utilizing the gravity and the siphon effect, and the treated water is sent to the water storage tank. Good. By not using the suction pump 43, treated water can be obtained at lower cost.
[0041]
When a membrane separation device is used, various separation membranes such as a flat membrane, a tubular membrane, a ceramic membrane, and a metal membrane can be used as the separation membrane used for the membrane separation apparatus. The material of the separation membrane may be any material capable of solid-liquid separation, and may be selected from polymers, metals, ceramics, and the like.
The average pore size of the separation membrane is preferably smaller than the average particle size of the adsorbent in order to prevent the adsorbent from flowing into the secondary side of the separation membrane, specifically, 0.01 to 5 μm, 0.1 to 1.0 μm is more preferable. When the average pore diameter of the hollow fiber membrane is 0.2 μm or less, microorganisms in the water to be treated can be almost completely captured on the membrane surface.
[0042]
In the water treatment method of the present invention, the amount of the adsorbent to be introduced into the water to be treated in the adsorption treatment step may be adjusted by an operator instead of being automatically adjusted by the control device 21.
For example, when the temperature of the water to be treated in the biological treatment step is 15 ° C. or less, the decrease in the biological treatment capacity due to the decrease in biological activity becomes remarkable. Is increased relative to the dosage at 20 ° C. It is preferable that the input amount at this time is increased from 5% by mass to 100% by mass with respect to the input amount at 20 ° C. If the rate of increase of the input amount is less than 5% by mass, the decrease in the ability of biological treatment in the biological treatment step cannot be compensated. If the rate of increase of the input amount exceeds 100% by mass, the cost of the adsorbent will only increase. Instead, the viscosity of the water to be treated increases, the load on the liquid feed pump and the like increases, and the maintenance cost also increases.
[0043]
On the other hand, when the temperature of the water to be treated in the biological treatment step is 25 ° C. or higher, the amount of the adsorbent to be added to the water to be treated in the adsorption treatment step is increased because the biological treatment capacity increases with an increase in biological activity. Can be reduced relative to the charge at 20 ° C. It is preferable that the input amount at this time is reduced by 5% by mass or more relative to the input amount at 20 ° C. If the reduction ratio of the input amount is less than 5% by mass, the merit of increasing the biological activity cannot be sufficiently enjoyed in the form of cost reduction of the absorbent.
[0044]
【Example】
Hereinafter, specific examples will be described.
[Example 1]
The water to be treated containing ammonium ions was treated using the water treatment system shown in FIG. As the first adsorption processing tank 23 and the second adsorption processing tank 25, those having a volume of 3 L were used, and as the membrane separation tank 41, those having a volume of 6 L were used.
As an adsorbent, zeolite (average particle size: 4.0 μm) having an action of adsorbing ammonium ions was used, and as an aggregating agent for coagulating the adsorbent, PFC (polyiron chloride) was used.
[0045]
The operating conditions of the water treatment system are as follows.
(1) Ammonium ion concentration in treated water: 100 mg / L
(2) Phosphorus concentration in the water to be treated: 10 mg / L
(3) Bacteria in the water to be treated: 1.2 × 10⁶ CFU / mL
(4) Turbidity of water to be treated: 3
(5) Water temperature of the water to be treated: 20 ° C
(6) Supply rate of the water to be treated to the first adsorption treatment apparatus 11: 2 L / hr
(7) Residence time of the water to be treated in the first adsorption treatment device 11 and the second adsorption treatment device 12: 1.5 hours each
(8) Zeolite concentration in the first adsorption processing apparatus 11 and the second adsorption processing apparatus 12: 3000 mg / L each
(9) Zeolite transfer speed by the adsorbent transfer device 17: 18 g / hr
(10) Recovery rate of used zeolite from the first adsorption treatment device 11: 18 g / hr
(11) Charge rate of fresh zeolite to the second adsorption treatment device 12: 18 g / hr
(12) The introduction of PFC (polyiron chloride) into the second adsorption treatment apparatus 12 was continuously performed so that the PFC concentration in the water to be treated became 10 ppm.
(13) Residence time of the water to be treated in the immersion type membrane separation device 40: 3 hours
(14) Fractionation characteristics of hollow fiber membrane: 0.1 μm
[0046]
Under the above conditions, the water treatment system was steadily operated to obtain treated water. The ammonium concentration of the treated water was 8.5 mg / L, and the phosphorus concentration was 0.8 mg / L. No bacteria were detected in the treated water. The turbidity of the treated water was 1. Thus, high quality treated water was obtained by the water treatment system shown in FIG.
[0047]
[Example 2]
The temperature of the water to be treated was changed to 30 ° C., and the water to be treated was treated in the same manner as in Example 1. The zeolite charging rate, zeolite transfer rate, and zeolite recovery rate were reduced by 10% from when the temperature of the water to be treated was 20 ° C.
(5) Water temperature of the water to be treated: 30 ° C
(8) Zeolite concentration in the first adsorption treatment device 11 and the second adsorption treatment device 12: 2700 mg / L each
(9) Zeolite transfer speed by the adsorbent transfer device 17: 16.2 g / hr
(10) Recovery rate of used zeolite from the first adsorption treatment device 11: 16.2 g / hr
(11) Feeding rate of fresh zeolite to the second adsorption treatment device 12: 16.2 g / hr
[0048]
Under the above conditions, the water treatment system was steadily operated to obtain treated water. The ammonium concentration of the treated water was 9.2 mg / L, and the phosphorus concentration was 0.6 mg / L. No bacteria were detected in the treated water. The turbidity of the treated water was 1. As described above, it was possible to obtain treated water having substantially the same water quality as that when the temperature of the treated water was 20 ° C.
[0049]
[Example 3]
The temperature of the water to be treated was changed to 13 ° C., and the water to be treated was treated in the same manner as in Example 1. The zeolite loading rate, zeolite transfer rate, and zeolite recovery rate were increased by 20% from when the temperature of the water to be treated was 20 ° C.
(5) Water temperature of the water to be treated: 13 ° C
(8) Zeolite concentration in the first adsorption treatment device 11 and the second adsorption treatment device 12: 3600 mg / L each
(9) Zeolite transfer speed by the adsorbent transfer device 17: 21.6 g / hr
(10) Used zeolite recovery rate from the first adsorption treatment device 11: 21.6 g / hr
(11) Input speed of fresh zeolite to the second adsorption treatment device 12: 21.6 g / hr
[0050]
Under the above conditions, the water treatment system was steadily operated to obtain treated water. The ammonium concentration of the treated water was 8.5 mg / L, and the phosphorus concentration was 0.8 mg / L. No bacteria were detected in the treated water. The turbidity of the treated water was 1. As described above, it was possible to obtain treated water having substantially the same water quality as that when the temperature of the treated water was 20 ° C.
[0051]
[Example 4]
The water to be treated was treated in the same manner as in Example 2 except that the water treatment system was changed to that shown in FIG. As the contact oxidation tank 27, a tank having a volume of 6 L was used. The zeolite loading rate, zeolite transfer rate, and zeolite recovery rate were reduced by 15% from when the temperature of the water to be treated was 20 ° C.
(5) Water temperature of the water to be treated: 30 ° C
(8) Zeolite concentration in the first adsorption processing apparatus 11 and the second adsorption processing apparatus 12: 2550 mg / L each
(9) Zeolite transfer speed by the adsorbent transfer device 17: 15.3 g / hr
(10) Used zeolite recovery rate from the first adsorption treatment device 11: 15.3 g / hr
(11) Charge rate of fresh zeolite to the second adsorption treatment device 12: 15.3 g / hr
Under the above conditions, the water treatment system was steadily operated to obtain treated water. The ammonium concentration of the treated water was 10.5 mg / L, and the phosphorus concentration was 0.8 mg / L.
[0052]
[Example 5]
The water to be treated was treated in the same manner as in Example 3, except that the water treatment system was changed to that shown in FIG. The zeolite loading rate, zeolite transfer rate, and zeolite recovery rate were increased by 20% from when the temperature of the water to be treated was 20 ° C.
(5) Water temperature of the water to be treated: 13 ° C
(8) Zeolite concentration in the first adsorption treatment device 11 and the second adsorption treatment device 12: 3600 mg / L each
(9) Zeolite transfer speed by the adsorbent transfer device 17: 21.6 g / hr
(10) Used zeolite recovery rate from the first adsorption treatment device 11: 21.6 g / hr
(11) Input speed of fresh zeolite to the second adsorption treatment device 12: 21.6 g / hr
Under the above conditions, the water treatment system was steadily operated to obtain treated water. The ammonium concentration of the treated water was 10.0 mg / L, and the phosphorus concentration was 0.9 mg / L.
[0053]
[Comparative Example 1]
The temperature of the water to be treated was changed to 13 ° C., and the water to be treated was treated in the same manner as in Example 1. However, the feeding speed of zeolite, the transfer speed of zeolite and the recovery speed of zeolite were the same as those when the temperature of the water to be treated was 20 ° C.
Under the above conditions, the water treatment system was steadily operated to obtain treated water. The ammonium concentration of the treated water was 28.5 mg / L and the phosphorus concentration was 3.8 mg / L, and the treatment capacity was reduced.
[0054]
【The invention's effect】
As described above, the water treatment system of the present invention includes an adsorption treatment means for adsorbing a target substance in the treatment water to an adsorbent, and a biological treatment for biologically treating the treatment water treated by the adsorption treatment means. Means, an adsorbent charging means for charging the adsorbent into the water to be treated by the adsorption processing means, a capacity detecting means for detecting the biological processing capability of the biological processing means, and a biological processing capacity detected by the capacity detecting means. Since the apparatus is provided with an input amount adjusting means for adjusting the input amount of the adsorbent in response, the target substance in the water to be treated can be removed at a low cost without a large change in the processing capacity depending on the water temperature.
[0055]
Further, the water treatment system of the present invention is provided with two or more adsorption treatment means, and further with an adsorbent transfer means for transferring the adsorbent used in the subsequent adsorption treatment means to the preceding adsorption treatment means. If it does, the adsorbent can be used efficiently.
Further, if the capacity detecting means is a temperature sensor, the ability of biological treatment in the biological treatment means can be easily detected.
[0056]
Further, the water treatment method of the present invention has an adsorption treatment step of adsorbing a target substance in the treatment water to an adsorbent, and a biological treatment step of biologically treating the treatment water treated in the adsorption treatment step. However, since the amount of the adsorbent to be added to the water to be treated in the adsorption treatment step is adjusted according to the biological treatment capacity in the biological treatment step, the treatment capacity does not greatly vary depending on the water temperature, and the cost is low. The target substance in the water to be treated can be removed.
[0057]
In addition, if the water treatment method of the present invention has two or more adsorption treatment steps, and the adsorbent used in the subsequent adsorption treatment step is reused in the previous adsorption treatment step, The efficient use of the adsorbent becomes possible.
In addition, if the ability of the biological treatment is estimated from the temperature of the water to be treated in the biological treatment step, the ability of the biological treatment in the biological treatment step can be easily detected.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing an example of a water treatment system of the present invention.
FIG. 2 is a schematic configuration diagram showing another example of the water treatment system of the present invention.
[Explanation of symbols]
11 1st adsorption processing apparatus (adsorption processing means)
12 Second adsorption processing device (adsorption processing means)
13 Catalytic oxidation equipment (biological treatment means)
15 Adsorbent input device (adsorbent input means)
17 Adsorbent transfer device (adsorbent transfer means)
20 temperature sensor (capability detection means)
21 control device (input amount adjustment means)
40 Immersion type membrane separation device (biological treatment means)

Claims

Adsorption treatment means for adsorbing the target substance in the water to be treated to the adsorbent,
Biological treatment means for biologically treating the water to be treated treated by the adsorption treatment means,
Adsorbent charging means for charging the adsorbent to the water to be treated by the adsorption processing means,
A capacity detecting means for detecting a capacity of biological treatment in the biological treatment means;
A water treatment system comprising: an input amount adjusting unit that adjusts an input amount of an adsorbent according to the biological treatment capability detected by the capability detection unit.

Comprising two or more adsorption treatment means,
2. The water treatment system according to claim 1, further comprising an adsorbent transfer means for transferring the adsorbent used in the latter adsorption treatment means to the former adsorption treatment means.

The water treatment system according to claim 1, wherein the capacity detection unit is a temperature sensor.

An adsorption treatment step of adsorbing the target substance in the water to be treated to the adsorbent,
Having a biological treatment step of biologically treating the water to be treated treated in the adsorption treatment step,
A water treatment method comprising: adjusting an amount of an adsorbent to be added to water to be treated in an adsorption treatment step according to a biological treatment ability in the biological treatment step.

Having two or more adsorption treatment steps,
5. The water treatment method according to claim 4, wherein the adsorbent used in the adsorption process in the post-process is reused in the adsorption process in the pre-process.

The water treatment method according to claim 4 or 5, wherein the capacity of the biological treatment is estimated from the temperature of the water to be treated in the biological treatment step.