JPH0952100A - Reduction of volume of organic sludge - Google Patents
Reduction of volume of organic sludgeInfo
- Publication number
- JPH0952100A JPH0952100A JP20713295A JP20713295A JPH0952100A JP H0952100 A JPH0952100 A JP H0952100A JP 20713295 A JP20713295 A JP 20713295A JP 20713295 A JP20713295 A JP 20713295A JP H0952100 A JPH0952100 A JP H0952100A
- Authority
- JP
- Japan
- Prior art keywords
- sludge
- aerobic digestion
- treatment
- organic
- solid
- 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.)
- Granted
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/20—Sludge processing
Landscapes
- Treatment Of Sludge (AREA)
Abstract
Description
【0001】[0001]
【発明の属する技術分野】本発明は、有機性廃水の処理
などにおいて生ずる余剰活性汚泥などの有機汚泥を大幅
に減量化する方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for significantly reducing the amount of organic sludge such as surplus activated sludge generated in the treatment of organic wastewater.
【0002】[0002]
【従来の技術】家庭下水などの有機性廃水を処理する活
性汚泥処理施設などからは多量の下水汚泥などの有機性
汚泥(以下、「原汚泥」ということもある)が発生して
おり、これらの有機性汚泥は余剰汚泥や生汚泥が含まれ
ていて、その発生量も下水道の施設の拡充に伴って増大
しており、現在この有機性汚泥の処理処分が最大の問題
となっている。従来、有機性汚泥は脱水助剤(有機高分
子ポリマーなど)を添加し、脱水機で脱水された後、焼
却処分されているが、汚泥が大量の場合には、脱水機及
び焼却炉が大規模なものになり、設備費、維持管理費な
どが多大の額となり、経済的にも困難となる。2. Description of the Related Art A large amount of organic sludge (hereinafter sometimes referred to as "raw sludge") such as sewage sludge is generated from activated sludge treatment facilities that treat organic wastewater such as domestic sewage. The organic sludge contains excess sludge and raw sludge, and the amount generated is increasing with the expansion of sewerage facilities. Currently, the treatment and disposal of this organic sludge is the biggest problem. Conventionally, organic sludge has been dehydrated with a dehydration aid (organic polymer, etc.) and then incinerated after being dehydrated. However, if a large amount of sludge is used, the dehydrator and incinerator are large. It becomes a large scale, and the equipment cost, the maintenance cost, etc. become enormous, and it becomes economically difficult.
【0003】この問題を解決する手段の1つとして、有
機性汚泥の減量化があり、それには種々の手段が提案さ
れており、従来よりその手段の1つである生物学的な汚
泥減量化方法として嫌気性消化法、好気性消化法が知ら
れているが、それらは長時間の滞留時間を必要とする割
りには減量化率が劣り、また難脱水性汚泥を生ずる等の
問題があり、最近はほとんど採用されていないのが実情
である。該有機性汚泥に対し加熱下で好気性消化をする
方法(特開昭55−34175号)も知られているが、
加熱費が高額であり、経済的な面などから実用性が乏し
いなどの欠点がある。One of the means for solving this problem is to reduce the amount of organic sludge, and various means have been proposed for it, and biological sludge reduction, which is one of the means, has been proposed. Anaerobic digestion method and aerobic digestion method are known as methods, but they have a problem that the reduction rate is inferior in comparison with the long residence time and that it produces hardly dehydratable sludge. The fact is that it has not been adopted recently. A method of aerobically digesting the organic sludge under heating is also known (JP-A-55-34175).
There are drawbacks such as high heating cost and poor practicability from the economical aspect.
【0004】[0004]
【解決しようとする課題】有機性廃水の活性汚泥処理法
などが効率的に実施できるようにするためには、そこか
ら生ずる有機性汚泥の減量化が長時間の処理を要せず、
また多くの熱エネルギーを要することなく行えるように
する技術の開発が必要であり、前記した欠点を解消する
ことが必要である。本発明は、好気性消化法を見直し、
有機性汚泥を効果的に減量化する新技術を提供すること
を課題とするものである。すなわち、本発明は、有機性
汚泥を効果的に減量化することによって、汚泥脱水機、
焼却炉に持ち込まれる汚泥量を大きく減少させ汚泥処理
工程を合理化することを課題とするものである。ここ
で、好気性消化とは汚泥を曝気し好気性条件下で所定時
間滞留させる操作をいうものである。[Problems to be solved] In order to efficiently carry out the activated sludge treatment method of organic wastewater, reduction of the amount of organic sludge generated therefrom does not require long-term treatment,
Further, it is necessary to develop a technique that can be performed without requiring a large amount of heat energy, and it is necessary to eliminate the above-mentioned drawbacks. The present invention reviews aerobic digestion,
It is an object to provide a new technology for effectively reducing the amount of organic sludge. That is, the present invention, by effectively reducing the amount of organic sludge, sludge dehydrator,
The objective is to greatly reduce the amount of sludge brought into the incinerator and to rationalize the sludge treatment process. Here, aerobic digestion refers to an operation in which sludge is aerated and retained for a predetermined time under aerobic conditions.
【0005】[0005]
【課題を解決するための手段】本発明は、生物学的な好
気性消化と物理化学的な可溶化処理を新規な態様で結合
させ、有機性汚泥の効果的な減量を実現したものであ
る。すなわち、本発明は、以下に示す手段により前記の
課題を解決することができた。 (1)有機性汚泥を好気性消化する第1の好気性消化工
程と、該好気性消化工程からの消化汚泥を固液分離する
固液分離工程と、該固液分離工程からの分離汚泥の少な
くとも一部を加熱及び/又はアルカリ処理して可溶化す
る可溶化工程と、該可溶化工程からの可溶化汚泥をさら
に好気性消化する第2の好気性消化工程を有することを
特徴とする有機性汚泥の減量化方法。 (2)前記第2の好気性消化工程が有機性汚水の活性汚
泥曝気処理工程であることを特徴とする前記(1)項記
載の有機性汚泥の減量化方法。 (3)前記可溶化工程からの可溶化汚泥を第1の好気性
消化工程へ返送させ、第1の好気性消化工程により第2
の好気性消化工程を兼ねさせることを特徴とする前記
(1)又は(2)項記載の有機性汚泥の減量化方法。The present invention realizes effective reduction of organic sludge by combining biological aerobic digestion and physicochemical solubilization treatment in a novel manner. . That is, the present invention was able to solve the above problems by the means shown below. (1) First aerobic digestion step for aerobically digesting organic sludge, solid-liquid separation step for solid-liquid separation of digested sludge from the aerobic digestion step, and separation sludge from the solid-liquid separation step An organic matter characterized by comprising a solubilization step of solubilizing at least a part of it by heating and / or alkali treatment, and a second aerobic digestion step of further aerobic digesting the solubilized sludge from the solubilization step. Reduction method of activated sludge. (2) The method for reducing the amount of organic sludge according to the item (1), wherein the second aerobic digestion step is an activated sludge aeration treatment step of organic wastewater. (3) The solubilized sludge from the solubilization step is returned to the first aerobic digestion step, and the second aerobic digestion step is performed.
The method for reducing the amount of organic sludge according to the above (1) or (2), which also serves as the aerobic digestion step.
【0006】勿論、活性汚泥法において一般に行われて
いるように、(1)において分離汚泥の一部を第1の好
気性消化工程へ返送しても良い。また、第2の好気性消
化工程においても汚泥の一部を返送利用することは差し
支えない。本発明においては、有機性汚泥をまず好気性
消化工程において好気性消化し、生物学的に分解され易
い部分を減量化する。その好気性消化の処理は、従来知
られている好気性消化の方法により行うものであって、
前記した「生物学的に分解され易い部分」は、有機性汚
泥の汚泥SS重量の30〜40重量%程度であって、そ
の処理において炭酸ガスや低分子量の可溶性の有機化合
物となる結果、有機性汚泥はその分減量化される。その
好気性消化工程で処理されて出た消化汚泥を固液分離工
程で遠心分離などの手段により固液分離し、そこで固体
分として分離される汚泥(「分離汚泥」という)を次の
可溶化工程に送る。この固液分離工程で分離される液
(「分離液」という)は、NOx −N濃度が低ければ放
流することができるが、高いものは生物学的処理などに
廻される。Of course, a part of the separated sludge may be returned to the first aerobic digestion step in (1), as is generally done in the activated sludge method. Also, in the second aerobic digestion step, it is possible to return and utilize a part of the sludge. In the present invention, the organic sludge is first aerobically digested in the aerobic digestion step to reduce the amount of the portion easily biodegradable. The aerobic digestion treatment is performed by a conventionally known aerobic digestion method,
The above-mentioned "biologically easily decomposed portion" is about 30 to 40% by weight of the sludge SS weight of the organic sludge, and as a result of being carbon dioxide gas or a low molecular weight soluble organic compound in the treatment, The amount of the sludge is reduced accordingly. The digested sludge that has been processed in the aerobic digestion process is subjected to solid-liquid separation by means such as centrifugation in the solid-liquid separation process, and the sludge that is separated as a solid component (called "separated sludge") is then solubilized. Send to the process. Liquid separated in this solid-liquid separation step (referred to as "separated liquid") can be released A low NO x -N concentration, high is routed to such biological treatment.
【0007】可溶化工程においては、この分離汚泥を目
的とする汚泥減量化率に応じて、加熱単独、アルカリ処
理単独、加熱アルカリ処理併用のいずれかを行う。この
中、加熱アルカリ処理併用の手段がもっとも高い減量化
率が得られる。次にアルカリ処理単独の手段が高い減量
化率を与える。加熱処理では、加熱温度は50〜100
℃、加熱時間は1〜3時間、アルカリ処理の場合のpH
は9〜12程度、処理時間は1〜2時間が好適である。
それに使用するアルカリ剤は苛性ソーダが好ましい。こ
の加熱処理において、分離汚泥中の汚泥成分は分解して
低分子化する。また、アルカリ処理においても、分離汚
泥中の汚泥成分はアルカリにより分解して低分子化す
る。両者の併用形式ではその分解が著しく促進される。In the solubilization step, either heating alone, alkali treatment alone, or heat alkali treatment combination is carried out depending on the target sludge reduction rate of the separated sludge. Among these, the method using the heating alkali treatment together provides the highest weight reduction rate. Next, the alkali treatment alone provides a high weight reduction rate. In the heat treatment, the heating temperature is 50 to 100.
C, heating time 1-3 hours, pH in the case of alkali treatment
Is about 9 to 12, and the processing time is preferably 1 to 2 hours.
The caustic soda is preferably used as the alkaline agent. In this heat treatment, the sludge components in the separated sludge are decomposed and reduced in molecular weight. In addition, even in the alkali treatment, the sludge components in the separated sludge are decomposed by the alkali to have a low molecular weight. The combined use of the two significantly promotes the decomposition.
【0008】その可溶化処理工程からの流出液は第2の
好気性消化工程に送られる。この第2の好気性消化工程
では、前記の流出液の有機成分を好気性消化することに
より主として炭酸ガスとして系の外に放出させる。この
第2の好気性消化工程は、先の第1の好気性消化工程と
別に設けた装置において行ってもよいが、第1の好気性
消化工程の装置で兼ねさせるようにすることもできる。
この第2の好気性消化工程において、先の可溶化工程に
おいて分解して低分子化された成分は好気性消化により
容易に炭酸ガス等となり、除去されるため、汚泥の量が
減少する。The effluent from the solubilization process is sent to the second aerobic digestion process. In this second aerobic digestion step, the organic component of the effluent is aerobically digested to release mainly as carbon dioxide gas out of the system. This second aerobic digestion step may be performed by a device provided separately from the first aerobic digestion step, but it may be performed by the device for the first aerobic digestion step.
In this second aerobic digestion step, the components that have been decomposed into low molecular weight in the previous solubilization step are easily converted into carbon dioxide gas and the like by aerobic digestion and are removed, so that the amount of sludge is reduced.
【0009】この全体の処理において、第1の好気性消
化工程を受ける結果、有機性汚泥の量が減少し、かつ固
液分離され、そこで分離された液が除かれるので、可溶
化処理工程に流入する汚泥量は、当初の有機性汚泥の量
よりも少なくなる。この結果、当初の有機性汚泥を単に
可溶化処理する方法に比較して、必要な加熱費、アルカ
リ剤費が減少するという利点がある。また、本発明にお
いては、第1の好気性消化時間は5〜7日程度、可溶化
処理後の好気性消化時間は3〜5日程度で十分その効果
を達成する。可溶化処理後の第2の好気性消化処理に
は、汚水(下水等)の活性汚泥処理工程の曝気槽又は第
1の好気性消化工程を利用することができる。In this whole treatment, as a result of undergoing the first aerobic digestion step, the amount of organic sludge is reduced and solid-liquid separation is carried out, and the separated liquid is removed, so that the solubilization treatment step is carried out. The amount of sludge that flows in will be less than the amount of organic sludge initially. As a result, there is an advantage that required heating cost and alkali agent cost are reduced as compared with the method of simply solubilizing the organic sludge at the beginning. Further, in the present invention, the first aerobic digestion time is about 5 to 7 days, and the aerobic digestion time after the solubilization treatment is about 3 to 5 days to achieve the effect sufficiently. For the second aerobic digestion treatment after the solubilization treatment, the aeration tank of the activated sludge treatment process of sewage (sewage or the like) or the first aerobic digestion process can be used.
【0010】[0010]
【発明の実施の形態】本発明の実施においては、その目
的とする有機性汚泥の減量化を最も効率的に、あるいは
最大限度で達成する上で、種々の形態を取ることができ
る。本発明の実施フロー例を図1ないし図3に示す。図
1は、第1の好気性消化処理と可溶化処理後の汚泥の第
2の好気性消化処理を別個の槽で行うものである。図2
は、可溶化処理後の汚泥を第1の好気性消化処理工程に
返送するものであって、槽の数を減らせる利点がある。
図3は、可溶化処理後の汚泥を有機性汚水の活性汚泥処
理の曝気槽に供給するものである。BEST MODE FOR CARRYING OUT THE INVENTION In carrying out the present invention, various forms can be adopted in order to achieve the target reduction of the amount of organic sludge most efficiently or to the maximum extent. An example of an implementation flow of the present invention is shown in FIGS. FIG. 1 shows that the first aerobic digestion treatment and the second aerobic digestion treatment of sludge after the solubilization treatment are performed in separate tanks. FIG.
Is for returning the sludge after the solubilization treatment to the first aerobic digestion treatment step, and has an advantage that the number of tanks can be reduced.
FIG. 3 shows that the sludge after the solubilization treatment is supplied to the aeration tank for the activated sludge treatment of the organic wastewater.
【0011】[0011]
【実施例】以下、実施例により本発明を具体的に説明す
る。 実施例1 下水の活性汚泥処理施設から発生する余剰活性汚泥(固
形物濃度12.0g/リットル)を第1の好気性消化工
程で温度が常温で、滞留日数5日の条件で好気性消化し
たところ、固形物濃度が7.2g/リットルに減少し
た。これを遠心分離機で固形物濃度が25g/リットル
に濃縮した。その際に分離される分離汚泥の量は当初の
汚泥(「原汚泥」という)の量の約1/3であった。そ
の分離汚泥に苛性ソーダを添加してpH11に調整し、
90℃で3時間攪拌した結果、固形物が可溶化し、固形
物濃度が6.2g/リットルに減少した。これを第2の
好気性消化工程で温度35℃、滞在日数7日の条件で好
気性消化した結果、固形物濃度は4.7g/リットルで
あった。従って、原汚泥の88.8%が減量したことに
なり、本発明の効果が実証された。The present invention will be described below in detail with reference to examples. Example 1 Excessive activated sludge (solids concentration: 12.0 g / liter) generated from an activated sludge treatment facility for sewage was aerobically digested in a first aerobic digestion step at a temperature of room temperature and a retention period of 5 days. However, the solid content concentration was reduced to 7.2 g / liter. This was concentrated with a centrifuge to a solid concentration of 25 g / liter. The amount of separated sludge separated at that time was about 1/3 of the amount of the original sludge (referred to as "original sludge"). Add caustic soda to the separated sludge to adjust the pH to 11,
As a result of stirring at 90 ° C. for 3 hours, the solid matter was solubilized and the solid matter concentration was reduced to 6.2 g / liter. This was subjected to aerobic digestion in the second aerobic digestion step under the conditions of a temperature of 35 ° C. and a staying period of 7 days, and as a result, the solid content was 4.7 g / liter. Therefore, the amount of raw sludge was reduced by 88.8%, demonstrating the effect of the present invention.
【0012】比較例 前記の余剰活性汚泥を第1の好気性消化工程、可溶化処
理をしただけのものは、最終的な処理物は固形物濃度が
6.2g/リットルであり、そのために必要とされる苛
性ソーダの量は実施例1の場合に比して約3.5倍も多
いものであった。Comparative Example The above-mentioned surplus activated sludge, which was only subjected to the first aerobic digestion step and solubilization treatment, had a solid concentration of 6.2 g / liter in the final treated product, which was necessary for that purpose. The amount of caustic soda was about 3.5 times as much as that in Example 1.
【0013】[0013]
【発明の効果】本発明によれば、有機性汚泥の減量効果
が大きく、加熱とアルカリ添加の併用の場合には約90
%もの減量を達成することができる。また、可溶化処理
に要する加熱費やアルカリ費を大幅に削減することがで
きる。最終的に汚泥を脱水処理するのに用いる汚泥脱水
機の規模が著しく小さいものでよく、その規模を縮小す
ることができる。EFFECTS OF THE INVENTION According to the present invention, the effect of reducing the amount of organic sludge is great.
As much as a% weight loss can be achieved. Further, the heating cost and alkali cost required for the solubilization treatment can be significantly reduced. The scale of the sludge dehydrator used to finally dehydrate the sludge may be extremely small, and the scale can be reduced.
【図1】図1は、本発明において、第1の好気性消化工
程と第2の好気性消化工程とを別個の槽で行う方法の場
合を示す。FIG. 1 shows a case of a method of performing the first aerobic digestion step and the second aerobic digestion step in separate tanks in the present invention.
【図2】図2は、可溶化汚泥を第1の好気性消化工程へ
返送し、第2の好気性消化工程を第1の好気性消化工程
で兼用させる本発明の処理方法の場合を示す。FIG. 2 shows a case of the treatment method of the present invention in which the solubilized sludge is returned to the first aerobic digestion step, and the second aerobic digestion step is also used in the first aerobic digestion step. .
【図3】図3は、可溶化汚泥を有機性廃水の活性汚泥曝
気槽へ送り、、第2の好気性消化工程を活性汚泥曝気槽
で兼用させる本発明の処理方法の場合を示す。FIG. 3 shows the case of the treatment method of the present invention in which the solubilized sludge is sent to the activated sludge aeration tank of the organic wastewater, and the second aerobic digestion step is also used in the activated sludge aeration tank.
Claims (3)
性消化工程と、該好気性消化工程からの消化汚泥を固液
分離する固液分離工程と、該固液分離工程からの分離汚
泥の少なくとも一部を加熱及び/又はアルカリ処理して
可溶化する可溶化工程と、該可溶化工程からの可溶化汚
泥をさらに好気性消化する第2の好気性消化工程を有す
ることを特徴とする有機性汚泥の減量化方法。1. A first aerobic digestion step for aerobically digesting organic sludge, a solid-liquid separation step for solid-liquid separation of digested sludge from the aerobic digestion step, and a separation from the solid-liquid separation step. A solubilization step of solubilizing at least a part of the sludge by heating and / or alkali treatment, and a second aerobic digestion step of further aerobic digesting the solubilized sludge from the solubilization step. Method for reducing organic sludge.
の活性汚泥曝気処理工程であることを特徴とする請求項
1記載の有機性汚泥の減量化方法。2. The method for reducing the amount of organic sludge according to claim 1, wherein the second aerobic digestion step is an activated sludge aeration treatment step of organic wastewater.
の好気性消化工程へ返送させ、第1の好気性消化工程に
より第2の好気性消化工程を兼ねさせることを特徴とす
る請求項1又は2記載の有機性汚泥の減量化方法。3. The solubilized sludge from the solubilization step is first
3. The method for reducing the amount of organic sludge according to claim 1 or 2, wherein the method is returned to the aerobic digestion step, and the first aerobic digestion step also serves as the second aerobic digestion step.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP20713295A JP3447024B2 (en) | 1995-08-14 | 1995-08-14 | How to reduce organic sludge |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP20713295A JP3447024B2 (en) | 1995-08-14 | 1995-08-14 | How to reduce organic sludge |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0952100A true JPH0952100A (en) | 1997-02-25 |
JP3447024B2 JP3447024B2 (en) | 2003-09-16 |
Family
ID=16534730
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP20713295A Expired - Fee Related JP3447024B2 (en) | 1995-08-14 | 1995-08-14 | How to reduce organic sludge |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3447024B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2016221491A (en) * | 2015-06-03 | 2016-12-28 | オルガノ株式会社 | Organic wastewater treatment method and organic wastewater treatment equipment |
-
1995
- 1995-08-14 JP JP20713295A patent/JP3447024B2/en not_active Expired - Fee Related
Cited By (1)
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