JP2004113983A - Fluorine or phosphorus-containing water treatment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently remove fluorine or phosphorus from water containing fluorine or phosphorus. <P>SOLUTION: In a zirconyl reaction tank 10, ZrO salt together with a polycondensate of phenol and formaldehyde is added to fluorine-containing water to insolubilize fluorine. In a flocculation tank 12, a polymer coagulant is added to the treated water from the zirconyl reaction tank 10 to perform flocculation. The treated water from the flocculation tank 12 is subjected to solid-liquid separation in a sedimentation tank 14 to efficiently remove fluorine or phosphorus from the water containing fluorine or phosphorus. The concentration of fluorine or phosphorus can be reduced in comparison with conventional anionic polymer coagulant by using both polycondensate of phenol and formaldehyde and ZrO salt. <P>COPYRIGHT: (C)2004,JPO

Description

【００２５】
フェノール類とホルムアルデヒド類の前記縮重合物は、水溶液に溶解させ、被処理水に添加したときに、被処理中で分散しやすくし、その反応スピードを高めることができる。前記縮重合物はアルカリ水溶液に溶解しやすいので、アルカリ水溶液に溶解したものを用いることがより好ましい。アルカリ水溶液にするために用いるアルカリ性物質としては、アルカリ金属、アルカリ土類金属等の水酸化物およびそれらの炭酸塩などの弱酸塩、アンモニア、アミン類等の水溶液であればよいが、好ましくは取り扱いが容易である水酸化ナトリウムや水酸化カリウムの水溶液である。アルカリ水溶液中における前記縮重合物の濃度は任意であるが、本実施形態では好ましくは重量パーセント濃度で１〜５０％の範囲である。前記縮重合物を含んだアルカリ水溶液の添加量は任意であるが、好ましくは１０〜数万ｍｇ／リットル（Ｌ）である。
【００２６】
本実施形態におけるジルコニル反応槽１０では、本実施形態で用いたＺｒＯ塩以外にも、金属の水溶性化合物として、ジルコニウムＺｒ、チタンＴｉ、ハフニウムＨｆ、バナジウムＶ、ニオブＮｂ、タンタルＴａの化合物として、塩化物、硫酸塩、硝酸塩、塩化酸化物、硫酸酸化物等が使用できる。また、希土類金属の化合物としては、スカンジウムＳｃ、イットリウムＹおよびランタノイドのランタンＬａ、セリウムＣｅ、プラセオジムＰｒ、ネオジムＮｄ、プロメチウムＰｍ、サマリウムＳｍ、ユウロピウムＥｕ、ガドリニウムＧｄ、テルビウムＴｂ、ジスプロシウムＤｙ、ホルミウムＨｏ、エルビウムＥｒ、ツリウムＴｍ、イッテルビウムＹｂ、ルテチウムＬｕの塩化物、硫酸塩、硝酸塩も使用できる。また、ジルコニル反応槽１０内はこれらが反応するのに最適なｐＨ、３〜７の範囲内にする必要があるが、ｐＨ４〜６の範囲内が好適である。
【００２７】
つぎにジルコニル反応槽１０の処理水は、沈殿槽１４に導入され、ここで固形物が沈殿分離される。すなわち、上述したフッ素を不溶化したＺｒＯ塩の凝集物が沈殿分離され、上澄み液としてフッ素濃度の低い処理水が得られる。
【００２８】
なお、凝集物を固液分離手段としては、沈殿槽１４に限定されることなく、各種の装置を利用することができる。特に、膜分離装置は、細かなＳＳまで確実に除去できるため、好適である。さらに、浮上分離、遠心分離、振動ふるいなども適宜利用可能である。
【００２９】
「実施形態２」
図２に、実施形態２の構成を示す。この実施形態２では、ジルコニル反応槽１０からの不溶化処理水を、直接沈殿槽１４に導入せず、凝集槽１２を介し沈殿槽１４に導入している。この凝集槽１２には、高分子凝集剤が供給され、ジルコニル反応槽１０で生成したフッ素の不溶化物が凝集粗大化され、その処理水が沈殿槽１４へと供給される。
【００３０】
ここで高分子凝集剤は、カチオン、アニオン、ノニオン性いずれの高分子凝集剤であってもよく、凝集効果のよいものを適宜採用する。例えば、アクリル酸とアクリルアミドの共重合物であるアニオン系高分子などが用いられている。なお、高分子凝集剤の分子量等は、特に限定されるわけではない。また、これら高分子凝集剤は、単独で又は混合物として用いることができる。さらに、これらの高分子凝集剤の添加量は任意に設定してよいが、凝集沈殿効果と経済性のバランスにより決定され、好ましくは添加量が１〜１００ｍｇ／リットル（Ｌ）の範囲である。
【００３１】
また、本実施形態で高分子凝集剤を添加する前に、無機凝集剤を添加することもできる。無機凝集剤としては、例えば硫酸第一鉄、硫酸第二鉄、ポリ硫酸鉄、塩化第一鉄、塩化第二鉄、ポリ塩化アルミニウム、硫酸アルミニウム（硫酸バンド）、塩化アルミニウム等の多価金属塩等を用いることができる。より好ましい凝集剤は、塩化第二鉄やポリ硫酸鉄である。これら無機凝集剤は、単独もしくは混合物として用いてもよい。
【００３２】
また、上述の金属の水溶性化合物、高分子凝集剤、無機凝集剤、ｐＨ調整剤、カルシウム塩などの各薬剤の種類や添加量、各槽における攪拌条件などは、最適となるように設定する。例えば、各薬剤の種類、添加量及び各槽における攪拌条件を変化させたジャーテストを行い、生じる凝集物のフロック径、固液分離性、発生汚泥量から容易に決定される。
【００３３】
「実施形態３、４」
図３、４は本発明の実施形態３、４をそれぞれ示すものである。この実施形態３、４では、実施形態１および実施形態２において、Ｚｒ反応層１０で添加する前記フェノール類とアルデヒド類の縮重合物を、ジルコニル反応槽１０の前段で予め添加している。
【００３４】
このような構成によっても、上記実施形態と同様にしてフッ素排水中のフッ素を除去することができる。
【００３５】
「実施形態５」
図５は、実施形態５の構成を示す図である。この実施形態５は、フッ素を高濃度で含有する排水に好適な構成である。すなわち、経済的観点から、本実施形態の希土類金属などを添加する処理は、フッ素濃度が低減された（好ましくは２０ｍｇ／Ｌ以下の）原水に適用することが好ましい。一方、エレクトロニクス産業排水などでは、フッ素濃度として、１００〜２０００ｍｇ／Ｌ程度である場合も多い。このような場合には、従来のカルシウム塩によるフッ素処理を行った後、残留するフッ素を本実施形態の実施形態１に示した処理によって除去することが好適である。
【００３６】
フッ素を高濃度で含有する原水は、まずカルシウム反応槽２０に導入される。このカルシウム反応槽２０には、消石灰や塩化カルシウムなどのカルシウム塩が供給される。なお、必要な場合には、水酸化ナトリウムなどのｐＨ調整剤も添加され、ｐＨがフッ化カルシウムの析出に適切なｐＨ（４〜１１程度）に調整される。カルシウム反応槽２０の処理水へのカルシウム塩添加量は、フッ素濃度を低減できれば良く、従来のフッ素処理以下の添加量でよい。
【００３７】
カルシウム反応槽２０において、カルシウム塩を添加しフッ化カルシウムを生成した後、そのままジルコニル反応槽１０に導入し、ここでＺｒＯ塩を添加すると同時にフェノール類とアルデヒド類の縮重合物を添加する。これによって、カルシウムと反応しなかった残留フッ素を不溶化することができる。
【００３８】
このような処理によって、高濃度のフッ素の大部分をカルシウム塩で除去し残留するフッ素を希土類金属などの水溶性化合物およびフェノール類とアルデヒド類の縮重合物によって効率的に除去することができる。
【００３９】
「実施形態６」
図６に、実施形態６の構成を示す。実施形態６では、ジルコニル反応槽１０と、沈殿槽１４の間に、凝集槽１２を設けている。このような処理によって、フッ素を低濃度にまで処理することができ、かつカルシウム塩や無機・有機凝集剤の添加量を比較的少なくすることができる。また、ＺｒＯ塩の添加量も比較的少なくてよい。なお、この処理においても、必要に応じて無機凝集剤を添加してもよい。
【００４０】
「実施形態７、８」
図７、８は、実施形態７、８をそれぞれ示す。実施形態７、８は、実施形態５、実施形態６のカルシウム反応槽２０において、前記フェノール類とアルデヒド類の縮重合物を添加したものである。これによって、前記実施形態３、４と同様に、ＺｒＯ塩を加えるジルコニル反応槽１０の前に、縮合物が予め添加される。
【００４１】
「その他」
上述の説明は、フッ素含有水の処理のみを対象とした。しかし、希土類金属、Ｔｉ、Ｚｒ、Ｈｆ、Ｖ、Ｎｂ、Ｔａのうち、少なくとも１種以上からなる金属の水溶性化合物は、リンに対しても、フッ素と同様の不溶化反応を起こす。そこで、上述の処理をそのままリン含有水に適用することができる。なお、リンは、リン酸カルシウムとして除去できるため、カルシウム塩を添加する処理もそのままリン含有水に適用することができ、例えば次の反応によりリンが不溶化される。なお、リンの形態はｐＨ等によって変化する。
【化３】
ＺｒＯＣｌ_２＋２Ｈ_２ＰＯ_４ ⁻→ＺｒＯ（Ｈ_２ＰＯ_４）_２＋２Ｃｌ⁻　（３）
ＺｒＯＣｌ_２＋ＨＰＯ_４ ^２−→ＺｒＯＨＰＯ_４＋２Ｃｌ⁻　　　　　　（４）
【００４２】
さらに、本発明は、フッ素とリンの両方を含有する水にも好適に適用できる。この場合、フッ素とリンの双方に対し当量以上の希土類金属塩等を添加すればよい。
【００４３】
【実施例】
「実験１」
フッ化ナトリウムを純水に溶解して、フッ素濃度２０ｍｇ−Ｆ／Ｌとなるようにしたものを調製し、これを原水として、処理実験を行った。
【００４４】
比較例１は、原水に、フッ素の不溶化剤としてジルコニウム含有率１０％の塩化酸化ジルコニウム水溶液を、５０ｍｇ−Ｚｒ／Ｌとなるように添加した。さらにｐＨ調整剤としてＮａＯＨを添加し、ｐＨ５に調整した。３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた。３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００４５】
比較例２は、比較例１で３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた後、高分子凝集剤を１ｍｇ／Ｌ添加する工程を加え、３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００４６】
実施例１は、フェノールとホルムアルデヒドの縮重合物を含むアルカリ水溶液を原水に添加し、同時にフッ素の不溶化剤としてジルコニウム含有率１０％の塩化ジルコニウム水溶液を、原水に５０ｍｇ−Ｚｒ／Ｌとなるように添加した。さらにｐＨ調整剤としてＮａＯＨを添加し、ｐＨ５に調整した。３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた。３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００４７】
実施例２は、実施例１で３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた後、高分子凝集剤を１ｍｇ／Ｌ添加する工程を加え、３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００４８】
実施例３は、フェノールとホルムアルデヒドの縮重合物を含むアルカリ水溶液を原水に添加し、実施例１とは異なり、３０分間攪拌した後、フッ素の不溶化剤としてジルコニウム含有率１０％の塩化酸化ジルコニウム水溶液を調製し、原水に５０ｍｇ−Ｚｒ／Ｌとなるように添加した。さらにｐＨ調整剤としてＮａＯＨを添加し、ｐＨ５に調整した。３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた。３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００４９】
実施例４は実施例３で３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた後、高分子凝集剤を１ｍｇ／Ｌ添加する工程を加え、３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００５０】
上記のように縮重合物の添加の有無及び時点、並びに高分子凝集剤の添加有無を変化させて実験した処理水中のフッ素濃度の結果を表１に示す。ここで縮重合物の添加の時点は上記の通り、ＺｒＯ塩の添加と同時かそれよりも前であるかで示している。
【表１】

【００５１】
このように、比較例１、２で示される縮重合物を用いていない処理水は、いずれも６．４ｍｇ−Ｆ／Ｌ以上であるのに対し、縮重合物を用いた実施例１〜４では２．３ｍｇ−Ｆ／Ｌ以下と比較例に対し約１／３倍以下にまで処理水中のフッ素濃度を低減できていることがわかる。一方、縮重合物の添加の時点、高分子凝集剤添加の有無は、縮合物添加の有無ほど結果に影響を与えないことがわかる。本実験では前に添加するほうが、また高分子凝集剤を添加したもののほうが、処理水中のフッ素濃度をより低減できることがわかる。これにより、縮重合物と高分子凝集剤は異なった効果を奏するものであることがわかる。実際に、処理水を目視すると比較例１，２は微細なフロックが見られ、白濁していたが、実施例１〜４では処理水の上澄み液が透明であった。これは、実施例では縮重合物により、フロックが沈殿槽に汚泥となって沈みやすくなり、処理水のフッ素を従来と比べ、より低減できたためと考えられる。
【００５２】
「実験２」
さらに、本発明の縮重合物を利用して、フッ素含有水の処理実験を行った。フッ化ナトリウムを純水に溶解して、フッ素濃度２００ｍｇ−Ｆ／Ｌとなるようにしたものを調製し、原水とした。
【００５３】
比較例３は、原水にフッ化カルシウムを生じさせるためにカルシウム塩として消石灰を１０００ｍｇ／Ｌ添加して、３０分間攪拌し、その後、フッ素の不溶化剤としてジルコニウム含有率１０％の塩化酸化ジルコニウム水溶液を、５０ｍｇ−Ｚｒ／Ｌとなるように添加した。さらにｐＨ調整剤としてＮａＯＨを添加し、ｐＨ５に調整した。３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた。３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００５４】
比較例４は、比較例３で３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた後、高分子凝集剤を１ｍｇ／Ｌ添加する工程を加え、３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００５５】
実施例５は、原水にフッ化カルシウムを生じさせるためにカルシウム塩として消石灰を１０００ｍｇ／Ｌ添加して、３０分間攪拌し、その後、フェノールとホルムアルデヒドの縮重合物を含むアルカリ水溶液を原水に添加し、同時にフッ素の不溶化剤としてジルコニウム含有率１０％の塩化酸化ジルコニウム水溶液を原水に５０ｍｇ−Ｚｒ／Ｌとなるように添加した。さらにｐＨ調整剤としてＮａＯＨを添加し、ｐＨ５に調整した。３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた。３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００５６】
実施例６は、実施例５で３０分間撹拌させることで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた後、高分子凝集剤を１ｍｇ／Ｌ添加する工程を加え、３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００５７】
実施例７は、フェノールとホルムアルデヒドの縮重合物を含むアルカリ水溶液を、実施例１とは異なり、カルシウム塩とともに原水に添加し、３０分間攪拌した後、フッ素の不溶化剤としてジルコニウム含有率１０％の塩化酸化ジルコニウム水溶液を原水に５０ｍｇ−Ｚｒ／Ｌとなるように添加した。さらにｐＨ調整剤としてＮａＯＨを添加し、ｐＨ５に調整した。３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた。３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００５８】
実施例８は実施例７で３０分間撹拌することで、十分にフッ素とジルコニウム塩を反応させ、不溶化物を生成させた後、高分子凝集剤を１ｍｇ／Ｌ添加する工程を加え、３０分間静置し、凝集物が十分に沈殿した後の上澄み液を処理水として採取し、処理水のフッ素濃度を測定した。
【００５９】
上記のように縮重合物添加の有無および時点、並びに高分子凝集剤の添加の有無を変化させて実験した処理水中のフッ素濃度の結果を表２に示す。ここで縮重合物添加の時点は上記の通り、ＺｒＯ塩の添加と同時かそれよりも前であるかで示している。
【表２】

【００６０】
このように、比較例３、４で示される縮重合物を用いていない処理水は、いずれも８．５ｍｇ−Ｆ／Ｌ以上であるのに対し、縮重合物を用いた実施例５〜８では３．８ｍｇ−Ｆ／Ｌ以下と比較例に対し約２／５倍以下にまで処理水中のフッ素濃度を低減できていることがわかる。一方、縮重合物添加の時点、高分子凝集剤添加の有無は、縮合物添加の有無ほど結果に影響を与えないことがわかる。本実験では前に添加するほうが、また高分子凝集剤を添加したもののほうが、処理水中のフッ素濃度をより低減できることがわかる。これにより、縮重合物と高分子凝集剤は異なった効果を奏するものであることがわかる。実際に、処理水を目視すると比較例３，４は微細なフロックが見られ、白濁していたが、実施例５〜８では処理水の上澄み液が透明であった。これは、実施例では縮重合物により、フロックが沈殿槽に汚泥となって沈みやすくなり、処理水のフッ素を従来と比べより低減できたためと考えられる。
【００６１】
【発明の効果】
以上説明したように、本発明によれば、フェノールとホルムアルデヒドの縮重合物を添加することにより、希土類金属、Ｔｉ、Ｚｒ、Ｈｆ、Ｖ、Ｎｂ、Ｔａの水溶性化合物の不溶化剤がフッ素やリンを不溶化させるのに適しているｐＨ３〜７（より好ましくは４〜６）において添加しても、効果的な凝集処理を行うことができる。そのため、フロックが沈殿槽において沈降しやすくなり、処理水のフッ素またはリンを従来と比べより低減することができる。
【図面の簡単な説明】
【図１】実施形態１の構成を示す図である。
【図２】実施形態２の構成を示す図である。
【図３】実施形態３の構成を示す図である。
【図４】実施形態４の構成を示す図である。
【図５】実施形態５の構成を示す図である。
【図６】実施形態６の構成を示す図である。
【図７】実施形態７の構成を示す図である。
【図８】実施形態８の構成を示す図である。
【符号の説明】
１０　ジルコニル反応槽、１２　凝集槽、１４　沈殿槽、２０　カルシウム反応槽。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for treating fluorine- or phosphorus-containing water, and particularly to a method for adding a water-soluble compound of at least one of rare earth metals, Ti, Zr, Hf, V, Nb, and Ta.
[0002]
[Prior art]
In the electronics industry that manufactures semiconductors, liquid crystals, and the like, fluorine is used in the manufacturing process, and thus the wastewater in the electronics industry often contains fluorine. As a method for removing the fluorine discharged from the fluorine-containing water, a calcium salt is added to raw water to precipitate fine particles of calcium fluoride, and these fine particles are made of an Al, Fe-based inorganic coagulant or A method of coagulating with a molecular coagulant and separating by precipitation is employed. According to this method, the amount of treated water fluorine can be reduced to 10 to 20 mg / l. However, in Japan, the emission standard for fluorine was increased from 15 mg / l to 8 mg / l in July 2001, and it became necessary to further treat fluorine.
[0003]
As a method of treating fluorine to a high degree, a method of increasing the amount of an aggregating agent added in the above-mentioned coagulation precipitation, or performing another coagulation precipitation again in the latter stage of the above coagulation precipitation treatment is employed. The amount of the inorganic coagulant used in such treatment is 2000 to 5000 mg / l, and fluorine is adsorbed on Al or Fe hydroxide to improve the fluorine removal rate. By this method, the concentration of fluorine in the treated water can be reduced to 2 to 8 mg / l.
[0004]
As another method, it has been proposed that a hydrated oxide of Zr or Ce is supported on a resin, or a fluorine adsorbent granulated with a polymer substance is used to improve the fluorine removal rate (Patent Document 1). (Japanese Patent Publication No. 6-79665) and Patent Document 2 (Japanese Patent Publication No. 61-47134). According to these methods, it is said that the treated water fluorine can be reduced to 0 to 1 mg / l.
[0005]
Here, the adsorbent is a hydrated oxide MO _n · XH ₂ O (≒ M (OH) _m ) generated by adding an alkali to a rare earth element or a salt of Ti or Zr or heating and hydrolyzing the salt. Utilizing such a property that a substance as shown exchanges anions with anions such as PO ₄ ³⁻ , F ⁻ , and SO ₄ ²⁻ on the acidic side and exchanges cations on the alkali side (Patent Document 3 (Patent Document 3)). Japanese Patent Publication No. 2-17220) and Patent Document 4 (JP-A-60-172353). M is a metal, and X, m, and n are arbitrary numbers.
[0006]
In addition, phosphorus is often contained in wastewater from the electronics industry, and phosphorus is also contained in wastewater from households. Phosphorus must be removed from the viewpoint of preventing eutrophication in closed water areas, and is subject to additional regulations in many areas. In order to remove phosphorus, similarly to the case of fluorine, a calcium salt is added and coagulated and precipitated as calcium phosphate, and an aluminum or iron-based inorganic coagulant is used to coagulate as aluminum phosphate or iron phosphate. A precipitation treatment method is used. Further, the above adsorbent can treat not only fluorine ions (F ⁻ ) but also phosphoric acid (PO ₄ ³⁻ ). Therefore, these adsorbents can be used for phosphorus removal.
[0007]
[Patent Document 1]
Japanese Patent Publication No. 6-79665 [Patent Document 2]
Japanese Patent Publication No. 61-47134 [Patent Document 3]
Japanese Patent Publication No. 2-17220 [Patent Document 4]
JP-A-60-172353
[Problems to be solved by the invention]
In the coagulation sedimentation method, several thousand mg / l of an Al or Fe-based inorganic coagulant is added to reduce fluorine or phosphorus. Such flocculated sludge incorporates water molecules into its floc, so that the sludge dewatering property is poor, and the amount of added flocculant increases the amount of generated sludge. Therefore, there is a problem that the sludge disposal cost increases. In addition, the process of generating such a large amount of waste is a technology that goes against the social demand for reducing the amount of waste.
[0009]
On the other hand, the fluorine adsorbent does not increase sludge, but has a low adsorption speed and a large amount of adsorbent used. For this reason, there is a problem that the processing cost is very high. There is also a problem that the adsorbent is degraded by the oxidizing agent such as hydrogen peroxide contained in the wastewater of the electronics industry and the hydrofluoric acid of the raw water, and the base material collapses and flows out.
[0010]
The present invention has been made in view of the above problems, and has as its object to provide a processing apparatus capable of efficiently removing fluorine or phosphorus from fluorine or phosphorus-containing water.
[0011]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a water-soluble compound of at least one metal selected from the group consisting of rare earth metals, Ti, Zr, Hf, V, Nb, and Ta, and condensation polymerization of phenols and aldehydes. And fluorine-containing or phosphorus-containing water.
[0012]
Further, the condensation polymer may be a condensation polymer of phenol and formaldehyde.
[0013]
Further, the polycondensate may be contained in an aqueous alkaline solution and added to water containing fluorine or phosphorus.
[0014]
The polycondensate may be added at the same time as or before the water-soluble metal.
[0015]
After adding the water-soluble compound of the metal and the condensation polymer, a polymer flocculant may be further added.
[0016]
As described above, in the present invention, a water-soluble compound of a rare earth metal, Ti, Zr, Hf, V, Nb, and Ta is added as a fluorine or phosphorus insolubilizing agent. These metals can insolubilize fluorine and phosphorus in an amount equivalent to a reaction formula equivalent to fluorine phosphorus. Therefore, the amount of addition is small and the amount of generated sludge is also small. Furthermore, the reaction product becomes a hydrate, and there is little possibility of taking in water, and the dewatering property of the generated sludge is improved. Therefore, the amount of generated sludge can be reduced, and the sludge disposal cost can be reduced.
[0017]
However, at a pH of 3 to 7 where a water-soluble metal compound such as a rare earth is suitable for insolubilizing fluorine and phosphorus, the floc tends to be fine, and solid-liquid separation cannot be sufficiently performed due to precipitation separation. There is.
[0018]
However, when fluorine or phosphorus is insolubilized by a water-soluble metal compound such as a rare earth element, if a condensation polymer of phenols and aldehydes is present, the water solubility of the rare earth metal, Ti, Zr, Hf, V, Nb, and Ta is reduced. At a pH of 3 to 7, more preferably 4 to 6, which is suitable for precipitating fluorine or phosphorus as an insolubilized substance, the polycondensation product of phenols and formaldehyde is insolubilized, and the insolubilized fluorine or phosphorus is insoluble. A relatively large floc can be obtained. Therefore, it is possible to prevent the insolubilized fluorine or phosphorus from leaking into the treated water, and it is possible to maintain the concentration of fluorine or phosphorus in the treated water sufficiently low.
[0019]
As the polycondensation product of phenols and aldehydes, those sold under the trade name "Orgafix DN-1 (trade name)" by Organo Corporation are suitable. This condensate is generally used to coagulate and remove nonionic surfactants and polyvinyl alcohol (PVA), but is also used to coagulate and remove insolubilized fluorine and phosphorus as in the present invention. It turned out to be effective.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention (hereinafter, referred to as embodiments) will be described. Note that the present embodiment is a preferred example for implementing the present invention, and the present invention is not limited to the present embodiment.
[0021]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a fluorine-containing wastewater is used as raw water, a water-soluble compound of ZrO salt (preferably ZrOCl ₂ ) is added as an insolubilizing agent of fluorine or phosphorus, and a condensation polymer of phenol and formaldehyde is added at the same time to promote condensation. Polymers dissolved in an aqueous alkali solution (Orgafix DN-1 (trade name)) are used.
[0022]
"Embodiment 1"
FIG. 1 is a diagram illustrating the configuration of the first embodiment. Raw water containing fluorine such as hydrofluoric acid is introduced into the zirconyl reaction tank 10. The zirconyl reaction tank 10 is supplied with an aqueous solution containing a ZrO salt (for example, zirconyl chloride (ZrOCl ₂ ) and a condensation polymer of phenol and formaldehyde, and a pH adjuster such as sodium hydroxide (pH of raw water is adjusted). An acid is supplied to lower the pH, and an alkali is supplied to raise the pH.The pH in the zirconyl reaction tank 10 is adjusted to 3 to 7, preferably 4 to 6 with a pH adjuster. In the reaction tank 10, the fluorine reacts with ZrO ²⁻ to become ZrOF ₂ and is insolubilized.
[0023]
That is,
Embedded image
ZrOCl ₂ + 2F ⁻ → ZrOF ₂ + 2Cl ⁻ (1)
By this reaction, fluorine is insolubilized. Further, the pH in the zirconyl reaction tank 10 is adjusted to a range of 3 to 7 with sodium hydroxide or the like. Thereby, the above-mentioned reaction proceeds rapidly.
[0024]
Here, the condensation polymer may be a condensation polymer of phenols and formaldehydes. Examples of phenols that can be used in the synthesis of this condensation polymer include phenol, σ-cresol, p-cresol, bromophenol, methylphenol, ethylphenol, xylenol, nitrophenol, pyrogallol, tannin, diphenol, dioxy Substances having a phenolic hydroxyl group, such as phenylpropane, dihydroxydiphenylsulfone, and mixtures thereof, can be mentioned. Aldehydes that can be used in the synthesis of the condensation polymer include, for example, formaldehyde, acetaldehyde, and mixtures thereof. As a typical and preferred example of a condensation polymer of phenols and aldehydes used in the present invention, the chemical structure of a condensation polymer of phenol and formaldehyde is represented by the following chemical formula (2). The number of repetitions n in the following chemical formula (2) is arbitrary, but is preferably 2 to 10, and more preferably 5 to 7 from the viewpoint of the aggregation effect.
Embedded image

[0025]
The polycondensate of phenols and formaldehydes can be dissolved in an aqueous solution and, when added to the water to be treated, can be easily dispersed during the treatment and the reaction speed can be increased. Since the condensation polymer is easily dissolved in an aqueous alkaline solution, it is more preferable to use one dissolved in an aqueous alkaline solution. The alkaline substance used to make the aqueous alkali solution may be an aqueous solution of an alkali metal, a hydroxide of an alkaline earth metal or the like, a weak acid salt such as a carbonate thereof, ammonia, an amine, or the like. Is an aqueous solution of sodium hydroxide or potassium hydroxide. The concentration of the polycondensate in the aqueous alkaline solution is arbitrary, but is preferably in the range of 1 to 50% by weight in this embodiment. The amount of the aqueous alkali solution containing the polycondensate is optional, but is preferably from 100 to several hundred thousand mg / liter (L).
[0026]
In the zirconyl reaction tank 10 in the present embodiment, in addition to the ZrO salt used in the present embodiment, as a water-soluble compound of a metal, zirconium Zr, titanium Ti, hafnium Hf, vanadium V, niobium Nb, a compound of tantalum Ta, Chloride, sulfate, nitrate, chloride oxide, sulfate oxide and the like can be used. Examples of the rare earth metal compounds include scandium Sc, yttrium Y and the lanthanide lanthanum La, cerium Ce, praseodymium Pr, neodymium Nd, promethium Pm, samarium Sm, europium Eu, gadolinium Gd, terbium Tb, dysprosium Dy, and holmium Ho. Erbium Er, thulium Tm, ytterbium Yb, and lutetium Lu chloride, sulfate, and nitrate can also be used. Further, the pH in the zirconyl reaction tank 10 needs to be within the range of 3 to 7 which is optimum for the reaction thereof, but the pH is preferably in the range of 4 to 6.
[0027]
Next, the treated water in the zirconyl reaction tank 10 is introduced into a precipitation tank 14, where solids are separated by precipitation. That is, the above-described aggregate of the ZrO salt in which fluorine has been insolubilized is separated by precipitation, and treated water having a low fluorine concentration is obtained as a supernatant.
[0028]
In addition, as a solid-liquid separation means of the aggregate, various devices can be used without being limited to the precipitation tank 14. In particular, a membrane separation device is preferable because it can reliably remove even fine SS. Further, flotation, centrifugal separation, vibrating sieve, and the like can be appropriately used.
[0029]
"Embodiment 2"
FIG. 2 shows the configuration of the second embodiment. In the second embodiment, the insolubilized water from the zirconyl reaction tank 10 is not directly introduced into the precipitation tank 14 but is introduced into the precipitation tank 14 via the coagulation tank 12. The coagulation tank 12 is supplied with a polymer coagulant, the insolubilized fluorine generated in the zirconyl reaction tank 10 is coagulated and coarsened, and the treated water is supplied to the precipitation tank 14.
[0030]
Here, the polymer flocculant may be any of a cationic, anionic and nonionic polymer flocculant, and a polymer having a good flocculating effect is appropriately employed. For example, an anionic polymer that is a copolymer of acrylic acid and acrylamide is used. The molecular weight and the like of the polymer flocculant are not particularly limited. These polymer flocculants can be used alone or as a mixture. Further, the amount of the polymer flocculant to be added may be arbitrarily set, but is determined by the balance between the flocculation effect and the economical efficiency, and is preferably in the range of 1 to 100 mg / liter (L).
[0031]
In addition, before adding the polymer flocculant in the present embodiment, an inorganic flocculant can be added. Examples of the inorganic flocculant include polyvalent metal salts such as ferrous sulfate, ferric sulfate, polyiron sulfate, ferrous chloride, ferric chloride, polyaluminum chloride, aluminum sulfate (sulfate band), and aluminum chloride. Etc. can be used. More preferred flocculants are ferric chloride and polysulfate. These inorganic coagulants may be used alone or as a mixture.
[0032]
Further, the types and amounts of the above-mentioned water-soluble compounds of metals, polymer coagulants, inorganic coagulants, pH adjusters, calcium salts and the like, and stirring conditions in each tank are set to be optimal. . For example, a jar test in which the type and amount of each chemical and the stirring conditions in each tank are changed is performed, and the jar test is easily determined from the floc diameter of the resulting aggregate, solid-liquid separation property, and the amount of generated sludge.
[0033]
"Embodiments 3 and 4"
3 and 4 show Embodiments 3 and 4 of the present invention, respectively. In Embodiments 3 and 4, in Embodiments 1 and 2, the condensation polymer of the phenols and aldehydes added in the Zr reaction layer 10 is added in advance in the zirconyl reaction tank 10.
[0034]
With such a configuration, fluorine in the fluorine wastewater can be removed in the same manner as in the above embodiment.
[0035]
"Embodiment 5"
FIG. 5 is a diagram illustrating a configuration of the fifth embodiment. The fifth embodiment is suitable for drainage containing a high concentration of fluorine. That is, from an economic viewpoint, the treatment of adding a rare earth metal or the like according to the present embodiment is preferably applied to raw water having a reduced fluorine concentration (preferably 20 mg / L or less). On the other hand, in the case of industrial industrial wastewater, the fluorine concentration is often about 100 to 2000 mg / L. In such a case, it is preferable to remove the remaining fluorine by the treatment described in Embodiment 1 of the present embodiment after performing the conventional fluorine treatment with a calcium salt.
[0036]
Raw water containing a high concentration of fluorine is first introduced into the calcium reaction tank 20. A calcium salt such as slaked lime or calcium chloride is supplied to the calcium reaction tank 20. If necessary, a pH adjuster such as sodium hydroxide is also added to adjust the pH to a suitable pH (about 4 to 11) for the precipitation of calcium fluoride. The amount of calcium salt added to the treated water in the calcium reaction tank 20 may be any amount as long as the fluorine concentration can be reduced, and may be an amount less than the conventional amount of fluorine treatment.
[0037]
In the calcium reaction tank 20, after adding calcium salt to generate calcium fluoride, the mixture is directly introduced into the zirconyl reaction tank 10, where the ZrO salt is added and simultaneously a condensation polymer of phenols and aldehydes is added. This makes it possible to insolubilize residual fluorine that has not reacted with calcium.
[0038]
By such a treatment, most of the high-concentration fluorine is removed with a calcium salt, and the remaining fluorine can be efficiently removed by a water-soluble compound such as a rare earth metal and a condensation polymer of phenols and aldehydes.
[0039]
"Embodiment 6"
FIG. 6 shows a configuration of the sixth embodiment. In the sixth embodiment, the coagulation tank 12 is provided between the zirconyl reaction tank 10 and the precipitation tank 14. By such a treatment, fluorine can be treated to a low concentration, and the addition amount of a calcium salt or an inorganic / organic coagulant can be relatively reduced. Further, the addition amount of the ZrO salt may be relatively small. In this treatment, an inorganic coagulant may be added as necessary.
[0040]
"Embodiments 7 and 8"
7 and 8 show Embodiments 7 and 8, respectively. Embodiments 7 and 8 are obtained by adding a condensation polymer of the phenols and aldehydes to the calcium reaction tank 20 of Embodiments 5 and 6. As a result, similarly to Embodiments 3 and 4, the condensate is added in advance before the zirconyl reaction tank 10 for adding the ZrO salt.
[0041]
"Other"
The above description has been directed only to the treatment of fluorine-containing water. However, a water-soluble compound of a metal composed of at least one of rare earth metals, Ti, Zr, Hf, V, Nb, and Ta also causes the same insolubilization reaction with phosphorus as fluorine. Therefore, the above-described treatment can be directly applied to the phosphorus-containing water. In addition, since phosphorus can be removed as calcium phosphate, the treatment of adding a calcium salt can be applied to phosphorus-containing water as it is, and for example, phosphorus is insolubilized by the following reaction. Note that the form of phosphorus changes depending on the pH and the like.
Embedded image
ZrOCl ₂ + 2H ₂ PO ₄ ⁻ → ZrO (H ₂ PO ₄ ) ₂ + 2Cl ⁻ (3)
ZrOCl ₂ + HPO ₄ ²⁻ → ZrOHPO ₄ + 2Cl ⁻ (4)
[0042]
Further, the present invention can be suitably applied to water containing both fluorine and phosphorus. In this case, it is sufficient to add a rare earth metal salt or the like in an equivalent amount or more to both fluorine and phosphorus.
[0043]
【Example】
"Experiment 1"
Sodium fluoride was dissolved in pure water to prepare a fluorine concentration of 20 mg-F / L, and this was used as raw water to conduct a treatment experiment.
[0044]
In Comparative Example 1, an aqueous solution of zirconium chloride having a zirconium content of 10% as a fluorine insolubilizing agent was added to raw water so as to be 50 mg-Zr / L. Further, NaOH was added as a pH adjuster to adjust the pH to 5. By stirring for 30 minutes, the fluorine and the zirconium salt were sufficiently reacted to generate an insolubilized product. The mixture was allowed to stand for 30 minutes, and after the aggregates were sufficiently precipitated, the supernatant was collected as treated water, and the fluorine concentration of the treated water was measured.
[0045]
Comparative Example 2 is a method in which the fluorine and the zirconium salt are sufficiently reacted by stirring for 30 minutes in Comparative Example 1 to generate an insolubilized substance, and then a step of adding a polymer flocculant at 1 mg / L is added, and then for 30 minutes. After standing, the supernatant liquid after the aggregates sufficiently precipitated was collected as treated water, and the fluorine concentration of the treated water was measured.
[0046]
In Example 1, an aqueous alkaline solution containing a condensation polymer of phenol and formaldehyde was added to raw water, and at the same time, a 10% zirconium chloride aqueous solution having a zirconium content of 10% as a fluorine insolubilizing agent was added to the raw water so as to be 50 mg-Zr / L. Was added. Further, NaOH was added as a pH adjuster to adjust the pH to 5. By stirring for 30 minutes, the fluorine and the zirconium salt were sufficiently reacted to generate an insolubilized product. The mixture was allowed to stand for 30 minutes, and after the aggregates were sufficiently precipitated, the supernatant was collected as treated water, and the fluorine concentration of the treated water was measured.
[0047]
In Example 2, a process of adding 1 mg / L of a polymer flocculant was added after the fluorine and the zirconium salt were sufficiently reacted by stirring for 30 minutes in Example 1 to generate an insolubilized substance. After standing, the supernatant liquid after the aggregates sufficiently precipitated was collected as treated water, and the fluorine concentration of the treated water was measured.
[0048]
Example 3 differs from Example 1 in that an alkaline aqueous solution containing a condensation polymer of phenol and formaldehyde is added to raw water, and after stirring for 30 minutes, an aqueous solution of zirconium chloride having a zirconium content of 10% is used as a fluorine insolubilizing agent. Was prepared and added to the raw water so as to be 50 mg-Zr / L. Further, NaOH was added as a pH adjuster to adjust the pH to 5. By stirring for 30 minutes, the fluorine and the zirconium salt were sufficiently reacted to generate an insolubilized product. The mixture was allowed to stand for 30 minutes, and after the aggregates were sufficiently precipitated, the supernatant was collected as treated water, and the fluorine concentration of the treated water was measured.
[0049]
In Example 4, a process of adding 1 mg / L of a polymer flocculant was added after the fluorine and zirconium salts were sufficiently reacted with each other by stirring for 30 minutes in Example 3 to generate an insolubilized substance, and the mixture was allowed to stand for 30 minutes. After the aggregates were sufficiently precipitated, the supernatant was collected as treated water, and the fluorine concentration of the treated water was measured.
[0050]
Table 1 shows the results of the fluorine concentration in the treated water that were tested by changing the presence and time of addition of the polycondensate and the presence or absence of the polymer flocculant as described above. Here, as described above, the point of addition of the polycondensate is indicated by whether it is simultaneous with or before the addition of the ZrO salt.
[Table 1]

[0051]
As described above, the treated water containing no polycondensate shown in Comparative Examples 1 and 2 is 6.4 mg-F / L or more, whereas Examples 1 to 4 using the polycondensate are used. It can be seen that the fluorine concentration in the treated water was reduced to 2.3 mg-F / L or less, which was about 1/3 or less of the comparative example. On the other hand, it can be seen that the presence or absence of the addition of the polymer flocculant at the time of addition of the condensation polymer does not affect the result as much as the presence or absence of addition of the condensate. In this experiment, it can be seen that the addition before the addition and the addition of the polymer flocculant can further reduce the fluorine concentration in the treated water. This indicates that the polycondensate and the polymer flocculant have different effects. Actually, when the treated water was visually observed, fine flocs were observed in Comparative Examples 1 and 2, and the treated water was cloudy, but in Examples 1 to 4, the supernatant of the treated water was transparent. This is presumably because in the examples, the floc was easily sludge as sludge in the sedimentation tank due to the polycondensate, and the fluorine in the treated water could be reduced more than before.
[0052]
"Experiment 2"
Furthermore, a treatment experiment of fluorine-containing water was conducted using the condensation polymer of the present invention. Sodium fluoride was dissolved in pure water to prepare a fluorine concentration of 200 mg-F / L, which was used as raw water.
[0053]
In Comparative Example 3, 1000 mg / L of slaked lime was added as a calcium salt in order to generate calcium fluoride in raw water, and the mixture was stirred for 30 minutes. Thereafter, an aqueous solution of zirconium oxide having a zirconium content of 10% was used as a fluorine insolubilizing agent. , 50 mg-Zr / L. Further, NaOH was added as a pH adjuster to adjust the pH to 5. By stirring for 30 minutes, the fluorine and the zirconium salt were sufficiently reacted to generate an insolubilized product. The mixture was allowed to stand for 30 minutes, and after the aggregates were sufficiently precipitated, the supernatant was collected as treated water, and the fluorine concentration of the treated water was measured.
[0054]
Comparative Example 4 is a process in which the fluorine and the zirconium salt are sufficiently reacted by stirring for 30 minutes in Comparative Example 3 to produce an insolubilized substance, and then a step of adding a polymer flocculant at 1 mg / L is added, and then for 30 minutes. After standing, the supernatant liquid after the aggregates sufficiently precipitated was collected as treated water, and the fluorine concentration of the treated water was measured.
[0055]
In Example 5, 1000 mg / L of slaked lime was added as a calcium salt in order to generate calcium fluoride in the raw water, and the mixture was stirred for 30 minutes. Thereafter, an alkaline aqueous solution containing a condensation polymer of phenol and formaldehyde was added to the raw water. At the same time, an aqueous solution of zirconium chloride having a zirconium content of 10% as a fluorine insolubilizing agent was added to the raw water so as to be 50 mg-Zr / L. Further, NaOH was added as a pH adjuster to adjust the pH to 5. By stirring for 30 minutes, the fluorine and the zirconium salt were sufficiently reacted to generate an insolubilized product. The mixture was allowed to stand for 30 minutes, and after the aggregates were sufficiently precipitated, the supernatant was collected as treated water, and the fluorine concentration of the treated water was measured.
[0056]
In Example 6, after stirring for 30 minutes in Example 5 to sufficiently react the fluorine and the zirconium salt to generate an insolubilized substance, a step of adding a polymer flocculant at 1 mg / L was added, and the mixture was added for 30 minutes. After standing, the supernatant liquid after the aggregates sufficiently precipitated was collected as treated water, and the fluorine concentration of the treated water was measured.
[0057]
In Example 7, unlike Example 1, an alkaline aqueous solution containing a condensation polymer of phenol and formaldehyde was added to raw water together with a calcium salt and stirred for 30 minutes, and then a zirconium content of 10% was used as a fluorine insolubilizing agent. An aqueous solution of zirconium chloride was added to the raw water at a concentration of 50 mg-Zr / L. Further, NaOH was added as a pH adjuster to adjust the pH to 5. By stirring for 30 minutes, the fluorine and the zirconium salt were sufficiently reacted to generate an insolubilized product. The mixture was allowed to stand for 30 minutes, and after the aggregates were sufficiently precipitated, the supernatant was collected as treated water, and the fluorine concentration of the treated water was measured.
[0058]
In Example 8, a process of adding 1 mg / L of a polymer flocculant was added after stirring for 30 minutes in Example 7 to sufficiently react fluorine and a zirconium salt to generate an insolubilized substance, and then allowed to stand for 30 minutes. After the aggregates were sufficiently precipitated, the supernatant was collected as treated water, and the fluorine concentration of the treated water was measured.
[0059]
Table 2 shows the results of the fluorine concentration in the treated water which were tested by changing the presence and time of addition of the polycondensate and the presence or absence of the polymer flocculant as described above. Here, as described above, the time of addition of the condensation polymer is indicated by whether it is simultaneous with or before the addition of the ZrO salt.
[Table 2]

[0060]
As described above, the treated water containing no polycondensate shown in Comparative Examples 3 and 4 is 8.5 mg-F / L or more, whereas Examples 5 to 8 using condensate are used. As a result, it can be seen that the fluorine concentration in the treated water can be reduced to 3.8 mg-F / L or less, about 2/5 or less of the comparative example. On the other hand, it can be seen that the presence or absence of the addition of the polymer flocculant at the time of addition of the condensation polymer does not affect the result as much as the presence or absence of the addition of the condensate. In this experiment, it can be seen that the addition before the addition and the addition of the polymer flocculant can further reduce the fluorine concentration in the treated water. This indicates that the polycondensate and the polymer flocculant have different effects. Actually, when the treated water was visually observed, fine flocs were observed in Comparative Examples 3 and 4, and the treated water was cloudy, but in Examples 5 to 8, the supernatant of the treated water was transparent. This is presumably because in the examples, the floc was easily sludge as sludge in the sedimentation tank by the polycondensate, and the fluorine in the treated water could be reduced more than before.
[0061]
【The invention's effect】
As described above, according to the present invention, by adding a condensation polymer of phenol and formaldehyde, the insolubilizing agent for the water-soluble compound of rare earth metal, Ti, Zr, Hf, V, Nb, and Ta is changed to fluorine or phosphorus. Can be effectively aggregated even when added at a pH of 3 to 7 (more preferably 4 to 6) which is suitable for insolubilizing. For this reason, the flocs tend to settle in the sedimentation tank, and the amount of fluorine or phosphorus in the treated water can be reduced as compared with the conventional case.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a first embodiment.
FIG. 2 is a diagram showing a configuration of a second embodiment.
FIG. 3 is a diagram illustrating a configuration of a third embodiment.
FIG. 4 is a diagram showing a configuration of a fourth embodiment.
FIG. 5 is a diagram showing a configuration of a fifth embodiment.
FIG. 6 is a diagram showing a configuration of a sixth embodiment.
FIG. 7 is a diagram showing a configuration of a seventh embodiment.
FIG. 8 is a diagram showing a configuration of an eighth embodiment.
[Explanation of symbols]
10 zirconyl reaction tank, 12 coagulation tank, 14 sedimentation tank, 20 calcium reaction tank.

Claims (5)

A water-soluble compound of at least one of rare earth metals, Ti, Zr, Hf, V, Nb, and Ta;
Polycondensates of phenols and aldehydes,
Is added to the fluorine- or phosphorus-containing water. The method according to claim 1, wherein the polycondensate is a polycondensate of phenol and formaldehyde. The method for treating fluorine- or phosphorus-containing water according to claim 1 or 2, wherein the polycondensate is added to fluorine- or phosphorus-containing water while being contained in an aqueous alkaline solution. The method for treating water containing fluorine or phosphorus according to any one of claims 1 to 3, wherein the polycondensate is added at the same time as or before the water-soluble metal. After adding the water-soluble compound of the metal and the condensation polymer,
The method for treating water containing fluorine or phosphorus according to claim 1, further comprising adding a polymer coagulant.

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