JPH0833898A - Treatment of organic sewage containing phosphorus - Google Patents
Treatment of organic sewage containing phosphorusInfo
- Publication number
- JPH0833898A JPH0833898A JP19122494A JP19122494A JPH0833898A JP H0833898 A JPH0833898 A JP H0833898A JP 19122494 A JP19122494 A JP 19122494A JP 19122494 A JP19122494 A JP 19122494A JP H0833898 A JPH0833898 A JP H0833898A
- Authority
- JP
- Japan
- Prior art keywords
- phosphorus
- adsorbent
- treated water
- organic wastewater
- treatment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
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- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
- Water Treatment By Sorption (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、し尿汚水、工場廃水、
下水などの有機性汚水を生物学的脱リン処理する場合の
新しいリン含有有機性汚水の処理方法を提供するもので
ある。特に、有機性汚水中のリンを安定して高度に除去
でき、沈殿汚泥の発生量を少なくできる新規リン含有有
機性汚水の処理方法に関するものである。BACKGROUND OF THE INVENTION The present invention relates to human waste water, industrial wastewater,
It is intended to provide a novel phosphorus-containing organic wastewater treatment method when biologically removing phosphorus from an organic wastewater such as sewage. In particular, the present invention relates to a novel phosphorus-containing organic wastewater treatment method capable of stably and highly removing phosphorus in organic wastewater and reducing the amount of sedimented sludge generated.
【０００２】[0002]
【従来の技術】下水などの有機性汚水中の汚染物質の１
つとしてリンがある。汚水中のリンを除去する技術とし
て種々研究開発されているが、中でも、有機性汚水を脱
リン処理する有効な方法の一つとして生物処理法があ
る。従来から、嫌気好気活性汚泥法による生物学的な脱
リン方法が知られている。しかし、この方法は汚水のリ
ンをある程度除去できるものの、安定してリンを高度に
除去することはできなかった。また、原水の水質変動と
くにＢＯＤ／Ｐ比が小さくなるとリン除去率が悪化する
という問題があった。また生物学的脱リン処理水に無機
凝集剤（ＣａＣｌ2）を添加して、残留するリンを除去
する方法は難脱水性の凝集汚泥（リン酸カルシウム等を
含む）が発生するため汚泥処理に負担を与えるという欠
点があった。2. Description of the Related Art One of pollutants in organic wastewater such as sewage
There is phosphorus as one. Various researches and developments have been carried out as a technique for removing phosphorus in wastewater, and among them, a biological treatment method is one of the effective methods for dephosphorizing organic wastewater. Conventionally, a biological dephosphorization method by an anaerobic aerobic activated sludge method has been known. However, although this method was able to remove phosphorus to some extent in the wastewater, it was not possible to stably and highly remove phosphorus. Further, there is a problem that the phosphorus removal rate deteriorates when the water quality variation of the raw water, especially the BOD / P ratio, decreases. In addition, a method of adding inorganic coagulant (CaCl 2 ) to biologically dephosphorized water to remove residual phosphorus causes coagulation sludge (including calcium phosphate, etc.) that is difficult to dehydrate, which is a burden on sludge treatment. There was a drawback of giving.
【０００３】[0003]
【発明が解決しようとする課題】本発明は、生物学的脱
リン処理方法に新たな技術思想を加え、前記の従来技術
の欠点を解決するものであり、リンを含む有機性汚水中
のリンを安定して高度に除去でき、活性汚泥の発生が少
ないリン含有有機性汚水の処理方法を提供することを目
的としている。DISCLOSURE OF THE INVENTION The present invention is to solve the above-mentioned drawbacks of the prior art by adding a new technical idea to the biological dephosphorization treatment method, and to remove phosphorus in organic wastewater containing phosphorus. It is an object of the present invention to provide a method for treating phosphorus-containing organic wastewater, which can stably and highly remove sewage and generate less activated sludge.
【０００４】[0004]
【課題を解決するための手段】本発明は、次の知見に基
づいて課題を解決する。すなわち生物学的脱リン処理水
には不可避的にリンが残留するが、この残留リンを活性
アルミナなどのリン吸着剤により除去し、リンが高度に
除去された処理水を得る。リン吸着剤のリン吸着量がほ
ぼ限度になる時点で、即ち、吸着処理後の処理水のリン
濃度が所定レベルに上昇した時点で吸着剤をアルカリ液
と接触させてリンを溶出させ、このリンを含むアルカリ
再生廃液を生物学的脱リン工程に返送して、再生廃液中
のリンを生物学的に脱リンするという知見である。この
新着想によって課題を解決できた。The present invention solves the problems based on the following findings. That is, although phosphorus remains inevitably in the biologically dephosphorized treated water, this residual phosphorus is removed by a phosphorus adsorbent such as activated alumina to obtain treated water in which phosphorus is highly removed. At the time when the phosphorus adsorption amount of the phosphorus adsorbent becomes almost the limit, that is, when the phosphorus concentration of the treated water after the adsorption treatment rises to a predetermined level, the adsorbent is contacted with an alkaline liquid to elute the phosphorus, and It is a finding that the alkaline reclaimed waste liquid containing is returned to the biological dephosphorization step to biologically dephosphorize phosphorus in the reclaimed waste liquid. This new idea solved the problem.
【０００５】即ち、本発明は、リンを含む有機性汚水を
生物学的に脱リンした後、該処理水をリン吸着剤と接触
させることにより、リンを高度に除去すると共に、間欠
的に該リン吸着剤をアルカリ液と接触させてリンをリン
吸着剤から液側に溶出させ、該溶出液を前記生物学的脱
リン工程に返送することを特徴とするリン含有有機性汚
水の処理方法である。又、リン吸着剤は充填層とするこ
とが好ましい。That is, according to the present invention, organic wastewater containing phosphorus is biologically dephosphorized, and then the treated water is brought into contact with a phosphorus adsorbent to highly remove phosphorus and intermittently remove the phosphorus. A method for treating phosphorus-containing organic wastewater, which comprises contacting a phosphorus adsorbent with an alkaline liquid to elute phosphorus from the phosphorus adsorbent to a liquid side, and returning the eluate to the biological dephosphorization step. is there. Further, the phosphorus adsorbent is preferably used as a packed bed.
【０００６】以上の方法によって、次の本発明独自の作
用が生じる。有機性汚水中のリンの大部分が、まず生物
学的脱リン処理によって活性汚泥に取り込まれ、除去さ
れる。その後、その処理水をリン吸着剤との接触によ
り、更にリンが高度に除去されるため、有機性汚水中の
リン濃度が変動した場合や、生物学的脱リン工程の脱リ
ン効果が悪化した場合も問題なく対応でき、常に高度な
リン除去効果が得られ、良好な処理水質が得られる。ま
た、リン吸着工程の再生廃液を処分するのに、生物学的
脱リンを利用するという新規な技術思想を用いたので、
再生廃液の処分に特別の設備が不要になり、イニシャル
コストやランニングコストを低減でき、更に再生廃液か
らは従来不可避であったＣａＣｌ2 等の無機凝集剤由来
の汚泥が発生しない。By the above method, the following unique action of the present invention occurs. Most of the phosphorus in organic wastewater is first taken up by activated sludge by biological dephosphorization treatment and removed. After that, the treated water is further removed by contacting it with a phosphorus adsorbent, so that the phosphorus concentration in the organic wastewater changes, and the dephosphorization effect of the biological dephosphorization process deteriorates. In this case, the problem can be dealt with without any problem, a high phosphorus removal effect can always be obtained, and good treated water quality can be obtained. In addition, since the new technical idea of utilizing biological dephosphorization was used to dispose of the recycled waste liquid in the phosphorus adsorption step,
No special equipment is required for the disposal of the regenerated waste liquid, the initial cost and running cost can be reduced, and sludge derived from an inorganic coagulant such as CaCl 2 which is conventionally inevitable is not generated from the regenerated waste liquid.
【０００７】以下に、図１を参照しながら本発明を具体
的に説明する。本発明の方法の一態様を示した図１にお
いては、生物学的脱リン工程としての生物学的脱リン槽
２、沈殿槽７及びリン吸着剤用のカラム１７から主に構
成される。生物学的脱リン槽２は、処理前半の嫌気部３
と後半の好気部４からなる。下水などのリン含有有機性
汚水１は、嫌気部３に導入され、次に好気部４が後続し
生物学的脱リン処理が行なわれる。好気部４には散気管
５が設置され、ブロワ６から空気が送り込まれる。好気
部４から流出する処理水は、沈殿槽７に送液され、流出
する活性汚泥は沈殿槽７において沈殿汚泥９として沈降
分離される。沈殿汚泥９の一部はリン含有率が高い余剰
汚泥１０として系外に排出される。他部は返送汚泥１１
として嫌気部３に循環される。沈殿汚泥９を除去した後
の生物脱リン処理水８にはリンが少量残留しているが活
性アルミナ等のリン吸着剤の充填槽１２に供給されてリ
ンが高度に除去された。The present invention will be described in detail below with reference to FIG. In FIG. 1 showing one embodiment of the method of the present invention, it is mainly composed of a biological dephosphorization tank 2 as a biological dephosphorization step, a precipitation tank 7 and a column 17 for a phosphorus adsorbent. The biological dephosphorization tank 2 has an anaerobic part 3 in the first half of the treatment.
And the aerobic part 4 in the latter half. Phosphorus-containing organic wastewater 1 such as sewage is introduced into the anaerobic part 3, and then the aerobic part 4 is followed to perform biological dephosphorization treatment. An air diffuser 5 is installed in the aerobic section 4, and air is sent from the blower 6. The treated water flowing out from the aerobic part 4 is sent to the settling tank 7, and the activated sludge flowing out is settled and separated as the settling sludge 9 in the settling tank 7. A part of the settled sludge 9 is discharged out of the system as an excess sludge 10 having a high phosphorus content. Other parts return sludge 11
Is circulated to the anaerobic section 3. Although a small amount of phosphorus remains in the biological dephosphorization-treated water 8 after removing the settled sludge 9, the phosphorus was highly removed by being supplied to the filling tank 12 of the phosphorus adsorbent such as activated alumina.
【０００８】処理を続けるにしたがって、充填槽１２中
のリン吸着剤の吸着能力が限界に達するので生物脱リン
処理水８の流入を停止し、リン吸着剤の再生を次のよう
に行なう。弁１４を閉じ、弁１５を開け、アルカリ溶液
１６をカラム１７に通水すると吸着剤からリンが脱着さ
れ、液側に溶出する。ここで、アルカリ溶液としてはＮ
ａＯＨ、ＫＯＨ等が好ましく、好適濃度としては２〜４
％である。アルカリ溶液１６を所定時間通水するとリン
の脱着が完了するのでアルカリ溶液１６の供給を止め、
生物脱リン処理水８を供給し、カラム１７の水洗を行な
う。水洗排水を含む再生廃液１８は貯槽１９に溜められ
た後、ポンプ２０によって少量ずつ生物学的脱リン槽２
に供給する。この結果、水洗排水を含む再生廃液１８中
のリンは生物学的に除去され、極めて合理的に処分でき
る。生物学的脱リン工程として、生物学的硝化脱窒素を
組み込んだプロセスを採用して良く、ゲル固定化微生物
を用いる方法を適用しても当然構わない。リン吸着剤に
は、活性アルミナのほかに鹿沼土、アロフェン、酸化ア
ルミニウム、水酸化ジルコニウム、水酸化チタン、水酸
化鉄等のリン吸着量の大きい物質を適用して良い。リン
吸着剤は粒状のほかに粉末、スラリ状のものを用いても
良い。リン吸着剤と生物脱リン処理水との接触手段とし
ては、充填層方式、流動層方式、攪拌接触法などの諸方
法が挙げられ、リン吸着剤の充填された充填槽に導入す
ることにより、該処理水とリン吸着剤を接触させること
が好ましい。これにより、リン除去効果が向上し、リン
の溶出がより速やかに行える。再生廃液１８を短時間に
一挙に生物脱リン工程に返送するとショックロードを生
物脱リン工程に与えてしまい、リン除去効果が悪化する
ので少量を長時間にわたって返送するのが好ましい。具
体的には、再生廃液量をＱリットル、再生頻度をＴ時間
とするとき、該返送量はＱ／Ｔリットル／ｈの範囲に設
定する。この場合、原水のＢＯＤを高めるように再生廃
液にＢＯＤ源を添加するようにしても良い。As the treatment is continued, the adsorption capacity of the phosphorus adsorbent in the filling tank 12 reaches the limit, so the inflow of the biological dephosphorized water 8 is stopped, and the phosphorus adsorbent is regenerated as follows. When the valve 14 is closed, the valve 15 is opened, and the alkaline solution 16 is passed through the column 17, phosphorus is desorbed from the adsorbent and eluted to the liquid side. Here, the alkaline solution is N
aOH, KOH and the like are preferable, and the preferable concentration is 2 to 4
%. When the alkaline solution 16 is passed for a predetermined time, the desorption of phosphorus is completed, so the supply of the alkaline solution 16 is stopped,
The biological dephosphorized water 8 is supplied and the column 17 is washed with water. The recycled waste liquid 18 including the washing drainage is stored in the storage tank 19 and then pumped by the pump 20 little by little to the biological dephosphorization tank 2
Supply to. As a result, the phosphorus in the reclaimed waste liquid 18 containing the washing wastewater is biologically removed and can be disposed extremely reasonably. As the biological dephosphorization step, a process incorporating biological nitrification and denitrification may be adopted, and a method using a gel-immobilized microorganism may be applied. As the phosphorus adsorbent, a substance having a large phosphorus adsorption amount such as Kanuma soil, allophane, aluminum oxide, zirconium hydroxide, titanium hydroxide, and iron hydroxide may be applied in addition to activated alumina. The phosphorus adsorbent may be in the form of powder or slurry in addition to the granular form. Examples of the contacting means between the phosphorus adsorbent and the biologically dephosphorized water include a packed bed method, a fluidized bed method, and a stirring contact method, and the like. It is preferable to bring the treated water into contact with the phosphorus adsorbent. This improves the phosphorus removal effect and allows the phosphorus to be eluted more quickly. When the recycled waste liquid 18 is returned to the biological dephosphorization step all at once in a short time, shock load is given to the biological dephosphorization step, and the phosphorus removal effect deteriorates. Therefore, it is preferable to return a small amount for a long time. Specifically, when the amount of waste liquid to be recycled is Q liters and the frequency of regeneration is T hours, the returned amount is set to the range of Q / T liters / h. In this case, a BOD source may be added to the regeneration waste liquid so as to increase the BOD of raw water.
【０００９】[0009]
【実施例】以下、実施例を示して、本発明の内容を具体
的に説明するが、本発明の内容がこれらに限定されるも
のではない。下水（平均水質ＳＳ１４０ｍｇ／リット
ル、ＢＯＤ１２０ｍｇ／リットル、リン濃度４．２ｍｇ
／リットル）を対象として本発明の実証試験を図１にし
たがって７か月間実験した。実験条件を表−１に示す。
この結果、処理中の生物脱リン処理水のリン濃度は０．
６〜１．３ｍｇ／リットルと変動したが、リン吸着カラ
ムからの処理水中のリン濃度は常に０．３ｍｇ／リット
ル以下であった。又、リン吸着カラムからの処理水中の
ＢＯＤ３ｍｇ／リットル、及びＳＳ２ｍｇ／リットルと
有機物、懸濁物も高度に除去された。余剰汚泥発生量は
下水１ｍ3 当たり１３５ｇであった。EXAMPLES The contents of the present invention will be specifically described below with reference to examples, but the contents of the present invention are not limited thereto. Sewage (average water quality SS 140 mg / liter, BOD 120 mg / liter, phosphorus concentration 4.2 mg
/ Liter), a verification test of the present invention was conducted for 7 months according to FIG. The experimental conditions are shown in Table-1.
As a result, the phosphorus concentration of the biologically dephosphorized water during the treatment was 0.
Although varying from 6 to 1.3 mg / liter, the phosphorus concentration in the treated water from the phosphorus adsorption column was always 0.3 mg / liter or less. Further, BOD 3 mg / liter and SS 2 mg / liter in the treated water from the phosphorus adsorption column as well as organic matter and suspension were highly removed. The amount of surplus sludge generated was 135 g per 1 m 3 of sewage.
【００１０】[0010]
【表１】 [Table 1]
【００１１】以上の結果から、本発明の実施例では、生
物学的脱リン処理のみの処理と比較して、７ヵ月間安定
して高度なリン除去が行えたことが示された。From the above results, it was shown that in the examples of the present invention, a high degree of phosphorus removal could be stably performed for 7 months, as compared with the treatment only by the biological phosphorus removal treatment.
【００１２】[0012]
【発明の効果】本発明のように、生物学的脱リン処理、
更にリン吸着剤によるリン吸着処理により、原水水質変
動、及び生物脱リン工程のリン除去効果の変動があって
も常にリン濃度の低い処理水が得られ、常に良好な水質
の処理水が得られる。無機凝集剤による吸着法によって
リン除去を行なう場合の問題点はリン吸着工程の再生廃
液からリンを含む汚泥が大量に発生する事であるが、本
発明では汚泥が殆ど発生しない。リン吸着剤の再生廃液
を生物学的脱リン工程に返送するので、リン吸着剤の再
生廃液の処分のための特別の設備が不要である。Industrial Applicability As in the present invention, biological dephosphorization treatment,
Furthermore, by the phosphorus adsorption treatment with a phosphorus adsorbent, treated water with a low phosphorus concentration can always be obtained even if there are fluctuations in the raw water quality and the phosphorus removal effect in the biological dephosphorization process, and treated water of good quality can always be obtained. . A problem in removing phosphorus by the adsorption method using an inorganic coagulant is that a large amount of sludge containing phosphorus is generated from the regenerated waste liquid in the phosphorus adsorption step, but in the present invention, sludge is hardly generated. Since the recycled waste liquid of the phosphorus adsorbent is returned to the biological dephosphorization process, no special equipment is required for the disposal of the recycled waste liquid of the phosphorus adsorbent.
【図１】本発明の方法の一態様を示した工程図である。FIG. 1 is a process chart showing one embodiment of the method of the present invention.
１ 有機性汚水 ２ 生物学的脱リン槽 ３ 嫌気部 ４ 好気部 ５ 散気管 ６ ブロワ ７ 沈殿槽 ８ 生物脱リン処理水 ９ 沈殿汚泥 １０ 余剰汚泥 １１ 返送汚泥 １２ リン吸着剤の充填槽 １３ 高度処理水 １４ 弁 １５ 弁 １６ アルカリ溶液 １７ カラム １８ 再生廃液 1 Organic Sewage 2 Biological dephosphorization tank 3 Anaerobic part 4 Aerobic part 5 Diffuser pipe 6 Blower 7 Precipitation tank 8 Biodephosphorization treated water 9 Precipitated sludge 10 Excess sludge 11 Return sludge 12 Phosphorus adsorbent filling tank 13 Advanced Treated water 14 valves 15 valves 16 alkaline solutions 17 columns 18 regeneration waste liquid
Claims (2)
ンした後、該処理水をリン吸着剤と接触させることによ
り、リンを高度に除去すると共に、間欠的に該リン吸着
剤をアルカリ液と接触させてリンをリン吸着剤から液側
に溶出させ、該溶出液を前記生物学的脱リン工程に返送
することを特徴とするリン含有有機性汚水の処理方法。1. An organic wastewater containing phosphorus is biologically dephosphorized, and then the treated water is brought into contact with a phosphorus adsorbent to highly remove phosphorus, and the phosphorus adsorbent is intermittently removed. A method for treating phosphorus-containing organic wastewater, which comprises contacting with an alkaline solution to dissolve phosphorus from the phosphorus adsorbent to the liquid side, and returning the eluted solution to the biological dephosphorization step.
ンした後の処理水を、リン吸着剤の充填された充填槽に
導入することにより、該処理水とリン吸着剤を接触させ
ることを特徴とする請求項１に記載のリン含有有機性汚
水の処理方法。2. The treated water after biologically dephosphorizing the organic wastewater containing phosphorus is introduced into a filling tank filled with the phosphorus adsorbent to bring the treated water and the phosphorus adsorbent into contact with each other. The method for treating phosphorus-containing organic wastewater according to claim 1, wherein
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19122494A JPH0833898A (en) | 1994-07-22 | 1994-07-22 | Treatment of organic sewage containing phosphorus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19122494A JPH0833898A (en) | 1994-07-22 | 1994-07-22 | Treatment of organic sewage containing phosphorus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0833898A true JPH0833898A (en) | 1996-02-06 |
Family
ID=16270965
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19122494A Withdrawn JPH0833898A (en) | 1994-07-22 | 1994-07-22 | Treatment of organic sewage containing phosphorus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0833898A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001058190A (en) * | 1999-08-20 | 2001-03-06 | Kurita Water Ind Ltd | Phosphorus-containing water treatment apparatus |
| KR101141928B1 (en) * | 2011-10-19 | 2012-05-14 | 코오롱워터앤에너지 주식회사 | A sewage or wastewater treatment apparatus and method using phosphorus collection and recycling coagulant |
| KR20220149474A (en) | 2021-04-30 | 2022-11-08 | 한국건설기술연구원 | Biological treatment plant for continuous feeding and intermittent discharge for advanced treatment of sewage and wastewater, and method for the same |
-
1994
- 1994-07-22 JP JP19122494A patent/JPH0833898A/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001058190A (en) * | 1999-08-20 | 2001-03-06 | Kurita Water Ind Ltd | Phosphorus-containing water treatment apparatus |
| KR101141928B1 (en) * | 2011-10-19 | 2012-05-14 | 코오롱워터앤에너지 주식회사 | A sewage or wastewater treatment apparatus and method using phosphorus collection and recycling coagulant |
| KR20220149474A (en) | 2021-04-30 | 2022-11-08 | 한국건설기술연구원 | Biological treatment plant for continuous feeding and intermittent discharge for advanced treatment of sewage and wastewater, and method for the same |
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