JPS5849320B2 - alkaline - Google Patents
alkalineInfo
- Publication number
- JPS5849320B2 JPS5849320B2 JP50055478A JP5547875A JPS5849320B2 JP S5849320 B2 JPS5849320 B2 JP S5849320B2 JP 50055478 A JP50055478 A JP 50055478A JP 5547875 A JP5547875 A JP 5547875A JP S5849320 B2 JPS5849320 B2 JP S5849320B2
- Authority
- JP
- Japan
- Prior art keywords
- bacteria
- bod
- cod
- activated sludge
- protozoa
- 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.)
- Expired
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
- Y02W10/10—Biological treatment of water, waste water, or sewage
Landscapes
- Micro-Organisms Or Cultivation Processes Thereof (AREA)
- Activated Sludge Processes (AREA)
- Physical Water Treatments (AREA)
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
Description
【発明の詳細な説明】
本発明は生活系廃液および産業系廃液のうちアルカリ性
廃液から窒素と同時に化学的酸素要求化合物(COD)
、生物学的酸素要求化合物(BOD)、浮遊物質(SS
)を除去する方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for removing chemical oxygen-demanding compounds (COD) from alkaline waste liquids among domestic waste liquids and industrial waste liquids at the same time as nitrogen.
, Biological Oxygen Demanding Compounds (BOD), Suspended Solids (SS
).
し尿あるいは下水に含まれる窒素はアルブミノイド態の
ものとアンモニア態のものが主体であり、常用の活性汚
泥処理や物理化学処理による除去は困難で、現在一応実
施容易で比較的安価な方法は、アンモニアストリツピン
グ法であるとされている。Nitrogen contained in human waste or sewage is mainly in the form of albuminoid and ammonia, and it is difficult to remove it by conventional activated sludge treatment or physical chemical treatment. It is said to be a stripping method.
この方法は原液にアルカリを加え大量の空気と接触させ
て原液中のアンモニアを大気中に拡散させるもので、本
発明者等は先にこのアンモニアストリツピング法におい
て、排出したアンモニア含有空気を触媒の存在下、酸化
分解除去すること、また浄化排ガスの熱を回収しストリ
ツピング系を加温することによりアンモニア除去を安定
にする方法を提案した。In this method, ammonia in the stock solution is diffused into the atmosphere by adding alkali to the stock solution and bringing it into contact with a large amount of air. We proposed a method to stabilize ammonia removal by oxidative decomposition and removal in the presence of ammonia, and by recovering heat from purified exhaust gas and heating the stripping system.
(特願昭4 9−7 7 8 7 0 ) Lかしなが
らこの方法で除去可能なのはPO43−の一部(アルカ
リによる)、アルブミノイド態窒素の一部とアンモニア
態窒素のみである。(Japanese Patent Application No. 49-77-870) However, only part of PO43- (by alkali), part of albuminoid nitrogen, and ammonia nitrogen can be removed by this method.
そして大部分のCOD,BOD,SSは除去できず、こ
れらは後工程、いわゆる二次処理のばつ気槽におけるエ
アレーションによる活性汚泥法を用いねばならない。Most of COD, BOD, and SS cannot be removed, and they must be treated using an activated sludge method using aeration in a so-called secondary treatment aeration tank.
したがってばつ気槽に広い面積が必要で、その中で長時
間処理した後はじめて放流し得る状態に達するのである
。Therefore, a large area is required for the aeration tank, and the product can only be discharged after being treated there for a long time.
本発明者等はアンモニア含有廃液の処理にあたり、アン
モニア態窒素およびアルブミノイド態窒素と同時にCO
D,BOD,SSをも除去し得る方法について研究した
結果、アンモニアストリッピングでは通常、処理液の1
000〜2000倍容量の空気でばつ気を行なうので、
これを利用して好アルカリ性微生物を活性汚泥化するこ
とによりCOD,BOD,SSをも同時に除去すること
を思い至って本発明に到達したものである。In the treatment of ammonia-containing waste liquid, the present inventors have discovered that CO2 is added at the same time as ammonia nitrogen and albuminoid nitrogen.
As a result of research on methods that can also remove D, BOD, and SS, we found that in ammonia stripping, one part of the processing solution is usually
Since the air is evacuated with 000 to 2000 times the volume,
The present invention was developed based on the idea of simultaneously removing COD, BOD, and SS by converting alkaliphilic microorganisms into activated sludge using this fact.
すなわち本発明は液温30〜50℃、pH9.5〜11
の範囲にしたアルカリ性廃液中に空気を送りこんでばっ
気して活性汚泥化し、好アルカリ性細菌を繁殖させてア
ンモニア態窒素を除くと同時に脱COD,脱BODおよ
び脱SSを行なうことを特徴とするアルカリ性廃液の処
理方法に関する。That is, in the present invention, the liquid temperature is 30 to 50°C, and the pH is 9.5 to 11.
An alkaline waste liquid characterized in that air is pumped into the alkaline waste liquid to aerate it to form activated sludge, and alkaliphilic bacteria are propagated to remove ammonia nitrogen and at the same time remove COD, BOD, and SS. Regarding the processing method.
活性汚泥とは、下水を長時間充分な酸素供給下で攪拌さ
れたときに形或される生物の集合体を指し、細菌、原生
動物、菌類、後生動物の4種類で構威されているが、特
に細菌類と原生動物が浄化の主役をになっている。Activated sludge refers to a collection of living organisms formed when sewage is stirred with sufficient oxygen supply for a long period of time, and is made up of four types: bacteria, protozoa, fungi, and metazoa. In particular, bacteria and protozoa play a major role in purification.
この生物集合体の浄化能は、集中体中の細菌による生物
学的酸化作用と、集合体そのものによる吸着作用の2つ
によって生じるといわれている。The purification ability of this biological aggregate is said to be caused by two factors: biological oxidation by the bacteria in the aggregate and adsorption by the aggregate itself.
生物学的酸化作用については、汚水中の有機物(BOD
,COD,SS)は好気性条件下で上記集合体中の細菌
により生物学的酸化作用で消費され、更に細菌は原生動
物により補食されることにより除去され汚水は浄化され
る。Regarding biological oxidation, organic matter (BOD) in wastewater
, COD, SS) are consumed by the bacteria in the aggregate under aerobic conditions through biological oxidation, and the bacteria are further removed by being eaten by protozoa, thereby purifying the wastewater.
以上のように有機物(BOD.COD,SS)→細菌→
原生動物の食物連鎖が構威されることにより浄化のメカ
ニズムが生れる。As mentioned above, organic matter (BOD.COD, SS) → bacteria →
A purification mechanism is created by disrupting the protozoan food chain.
このように原生動物が細菌と食物連鎖の関係にあるので
、運転条件、原水等の変化により細菌の変化(優占種の
変化等)が起ると原生動物にも変化が生じるので、原生
動物に注目すれば細菌およびひいては活性汚泥運転条件
、原水水質や浄化能力をも知ることができる。In this way, protozoa are in a food chain relationship with bacteria, so if there is a change in bacteria (such as a change in the dominant species) due to changes in operating conditions or raw water, changes will also occur in protozoa. By paying attention to this, we can learn about bacteria, activated sludge operating conditions, raw water quality, and purification ability.
すなわち原生動物が良好に存在する環境は細菌にも良好
なものであり浄化力も高いといえる。In other words, an environment where protozoa exist favorably is also favorable for bacteria and has a high purifying power.
この原生動物は普通37℃以下、pH 7〜8で増殖す
るがpH11付近で存在する種類があり、この種が十分
に生棲できるということは高いpH.で生棲する細菌が
あり、高いpHの原水の処理が可能ということである。This protozoan normally grows at a temperature below 37°C and a pH of 7 to 8, but there are some species that exist at a pH of around 11. This means that there are bacteria that live in the water, making it possible to treat raw water with a high pH.
本発明はこのアルカリ側で生棲する細菌を活性汚泥に利
用し、同様にアルカリ側で生棲する原生動物と組合わせ
ることによりpHの高い廃水を処理するところに特徴を
有する。The present invention is characterized in that it uses bacteria that live on the alkaline side in activated sludge and combines them with protozoa that also live on the alkaline side to treat high pH wastewater.
本発明で用いられる好アルカリ性細菌は、多《は土壌中
に土壌11中に10’個程度の割合で生存しており、た
とえばバチルス(桿状菌)A40−2があり、これはp
H7.5〜11位の範囲で生育できる。The alkaliphilic bacteria used in the present invention live in the soil at a ratio of about 10' in the soil, for example, Bacillus (rod-shaped bacterium) A40-2, which is
It can grow in the range of H7.5 to H11.
またバチルスA 2 2 1の生産するタンパク質分解
酵素であるアルカリプロテアーゼは酵素作用のための最
適pHがアルカリ側にありpH 1 3においても十分
に酵素作用があるという特徴がある。Furthermore, alkaline protease, which is a proteolytic enzyme produced by Bacillus A 2 2 1, has the characteristic that the optimum pH for enzymatic action is on the alkaline side, and that it has sufficient enzymatic action even at pH 13.
なおこれは洗剤に対する安定性もあり、耐熱性も極めて
よい。Additionally, it is stable against detergents and has extremely good heat resistance.
生育の速度と温度は今まで見出されたもので60℃が最
高で、現在のところ多くのものの最適温度は30〜37
゜Cである。The highest growth rate and temperature found so far is 60℃, and currently the optimum temperature for many species is 30-37℃.
It is °C.
コノ他ノ好アルカリ性細菌としてはバチルスサビリス(
Bacillus Subtilis )等があり、
これらは通常の活性汚泥と同様に、運転条件(温度、p
H、負荷等)や原水基質に慣れさせるため馴致という操
作を行なってはじめて処理可能となる。Bacillus subilis (
Bacillus Subtilis ), etc.
Similar to normal activated sludge, these are subject to operating conditions (temperature, p.
Treatment is possible only after an acclimatization operation is performed to get the animals used to the raw water substrate (H, load, etc.) and the raw water substrate.
好アルカリ性微生物を馴致し活性汚泥化すればこれを補
食する原生動物もアルカリ性で十分に存在し生棲するこ
とは可能であり、例えば繊毛虫類のコルポダ( Col
poda )のある種はPH3〜11の範囲のpH域で
存在している。If alkaliphilic microorganisms are acclimatized and turned into activated sludge, protozoa that feed on them can also exist in sufficient alkaline conditions and can survive, such as the ciliate Colpoda (Col).
Some species of P. poda) exist in the pH range from PH3 to 11.
この活性汚泥では37℃以下、アルカリ性で有機物(B
OD、COD,SS物質)→活性汚泥好アルカリ性細菌
→好アルカリ性原生動物という食物連鎖が構成され、原
水(一次処理液中)のBOD,COD、SSが除去され
る。In this activated sludge, the temperature is below 37℃, it is alkaline and organic matter (B
A food chain consisting of OD, COD, SS substances) → activated sludge alkalophilic bacteria → alkaliphilic protozoa is formed, and BOD, COD, and SS from the raw water (in the primary treatment liquid) are removed.
また運転温度条件についても活性汚泥は55℃でも高い
BOD,COD除去能を持つといわれる。Regarding operating temperature conditions, activated sludge is said to have high BOD and COD removal ability even at 55°C.
( Shindala 1 9 7 0 )。(Shindala 1970).
高温では一定量の微生物が多くの有機物を処理でき、水
の粘性が低下するために汚泥粒子の凝集や沈殿が円滑に
行なわれ、反応速度の増加、病原性微生物の死滅など多
くの利点がある。At high temperatures, a certain amount of microorganisms can process a large amount of organic matter, and because the viscosity of water is reduced, sludge particles can coagulate and settle smoothly, which has many advantages such as increasing the reaction rate and killing pathogenic microorganisms. .
好アルカリ性細菌は60’C付近で生棲するものもある
ので45〜50℃の範囲で繁殖する好アルカリ性細菌を
馴致し活性汚泥化すれば高温アルカリ性廃水処理も可能
である。Since some alkaliphilic bacteria live at around 60'C, it is possible to treat high-temperature alkaline wastewater by adapting alkaliphilic bacteria that breed in the range of 45 to 50C and turning it into activated sludge.
また処理水中に懸濁している細菌は原生動物によって凝
集させなげればならない。Also, bacteria suspended in the treated water must be flocculated by protozoa.
すなわち原生動物の存在する場合と細菌のみの場合での
活性汚泥処理水質を比較すると、原生動物が存在する場
合は透明な処理水が得られ、存在しない場合に比べSS
、COD,BOD、有機性窒素も著して低く、全生菌類
や大腸菌群の除去にも有効である。In other words, when comparing the quality of activated sludge treated water when protozoa are present and when only bacteria are present, clear treated water is obtained when protozoa are present, and SS is lower than when protozoa are present.
, COD, BOD, and organic nitrogen are also extremely low, and it is also effective in removing all living bacteria and coliform bacteria.
( Curds :l969、Pike &Curds
1 9 7 1 )。(Curds: l969, Pike & Curds
1971).
また原生動物を利用すればより多くの廃水中のBOD、
COD,SSを除去でき、当然活性汚泥状態も細菌のみ
よりは良くなり、また原生動物が存在することは活性汚
泥が一生態系として安定しており、食物連環により有機
物、生物のバランスがとれているということである。Also, if protozoa are used, more BOD,
COD and SS can be removed, and the condition of activated sludge is naturally better than that of bacteria alone. Also, the presence of protozoa means that activated sludge is stable as an ecosystem, and the balance of organic matter and living things is maintained through the food chain. It means that there is.
したがって細菌のみの場合より原生動物が存在した方が
より良い処理水質が得られる。Therefore, better treated water quality can be obtained when protozoa are present than when only bacteria are present.
一方原生動物は37℃以上では生棲テキナいので、良質
な処理水を得たいときには更に水温を下げればよい。On the other hand, protozoa cannot survive at temperatures above 37°C, so if you want to obtain high-quality treated water, you can lower the water temperature even further.
即ち温度条件により次の2つの処理法がある。That is, there are the following two processing methods depending on the temperature conditions.
そして温度を下げることによってバルキングがある程度
抑制できる。By lowering the temperature, bulking can be suppressed to some extent.
一方発生するアンモニア含有空気はそのまま大気中に放
散してもよいが、前述の方法(特願昭49−77870
)のように触媒によって比較的低温で酸化分解し、更に
そのようにして得られた排ガスの熱を前記ストリツピン
グの際に使用することが好ましい。On the other hand, the generated ammonia-containing air may be released into the atmosphere as it is, but the method described above (Japanese Patent Application No. 77870/1989
), it is preferable to carry out oxidative decomposition using a catalyst at a relatively low temperature, and to use the heat of the exhaust gas thus obtained in the stripping process.
酸化分解の際の触媒はクロム系などアンモニア酸化触媒
ならば何でもよく、酸化分解温度は250〜400℃で
ある。Any catalyst for oxidative decomposition may be used as long as it is an ammonia oxidation catalyst such as a chromium-based catalyst, and the oxidative decomposition temperature is 250 to 400°C.
本発明方法によりアンモニア含有廃液からの脱窒素と同
時にBOD,COD,SSを除くことができ、その際の
工程数も一工程ですみ、その除去率も90%以上と高い
ものである。By the method of the present invention, BOD, COD, and SS can be removed at the same time as denitrification from an ammonia-containing waste liquid, and only one step is required, and the removal rate is as high as 90% or more.
次に本発明を添付図面にしたがって更に詳細に説明する
。Next, the present invention will be explained in more detail with reference to the accompanying drawings.
pH9〜11で、COD500〜1000ppm1BO
D1000ppm、アンモニア態窒素1000〜3 0
0 0 ppmを含む廃液をライン1からpH調整槽
2に導入し、NaOHまたはCa(OH)2等のアルカ
リを加えてpHを10〜11に調整する。At pH 9-11, COD 500-1000ppm1BO
D1000ppm, ammonia nitrogen 1000-30
A waste liquid containing 0.0 ppm is introduced from line 1 into pH adjustment tank 2, and the pH is adjusted to 10 to 11 by adding an alkali such as NaOH or Ca(OH)2.
なお廃液のpHがはじめからこの範囲にあるときはpH
調整槽2を省略できる。In addition, if the pH of the waste liquid is within this range from the beginning, the pH
The adjustment tank 2 can be omitted.
pHを調整した廃液はライ/3からばつ気槽4に導入す
る。The pH-adjusted waste liquid is introduced into the aeration tank 4 from Lie/3.
このばつ気槽4には、ライン5−脱CO2槽6一熱交換
器7−ライン8−ブロア9−ライン10を経た空気を送
る。Air is sent to this aeration tank 4 through a line 5 - a CO2 removal tank 6 - a heat exchanger 7 - a line 8 - a blower 9 - a line 10.
ばっ気槽で脱窒素、脱BOD、脱COD、脱SSを終え
た廃液および汚泥の一部をライン11かも希釈調整槽1
2に導入して酸性物質でpHを8.5に調整すると共に
水で希釈する。Part of the waste liquid and sludge that have been denitrified, BOD, COD, and SS removed in the aeration tank is transferred to line 11 or dilution adjustment tank 1.
2 and adjust the pH to 8.5 with an acidic substance and dilute with water.
この調整槽を出た液はライン13より沈殿槽14に導入
して上澄液はライン15かも放流し、沈殿した汚泥の一
音巨まライン17から曝気槽4に返送し、余剰の汚泥は
ライン16から排出する。The liquid exiting this adjustment tank is introduced into the settling tank 14 through line 13, the supernatant liquid is also discharged through line 15, and the settled sludge is returned to the aeration tank 4 through line 17, and the excess sludge is Discharge from line 16.
この活性汚泥工程の条件は次の様である。The conditions for this activated sludge process are as follows.
BOD−MLSS負荷0.3〜0. 4.kg/M L
S S kg・d、汚泥返送率25%、MLS 8
3 0 0 0 〜4 0 0 0 ppm,空気量4
.0 〜1 5.0 m”/分、BOD容積負荷1〜1
.7kg/m3・d、ばつ気時間8〜14時間である。BOD-MLSS load 0.3~0. 4. kg/ML
S S kg・d, sludge return rate 25%, MLS 8
3000 to 4000 ppm, air amount 4
.. 0 to 1 5.0 m”/min, BOD volumetric load 1 to 1
.. 7 kg/m3·d, exposure time 8 to 14 hours.
ライン15からの放流水はBOD40〜20pμ、CO
D80〜40ppm、アンモニア態窒素15ppm,S
S40 〜20ppm(GFP法による)を含有する。The water discharged from line 15 has a BOD of 40 to 20 pμ and a CO
D80-40ppm, ammonia nitrogen 15ppm, S
Contains S40 to 20 ppm (according to the GFP method).
一方ばつき槽から排出される3 0 0 0 ppmの
アンモニアを含有する空気はライン18から触媒塔19
に入り、ここで酸化分解を受けアンモニア含有量3 0
ppmとなってライン20から熱交換器7に入ってば
つ気槽に送る空気を暖めた後ライン21から、ライン2
2からの空気と共に排気塔23に入り、アンモニア含有
量5 ppm、となってライン24かも放出される。On the other hand, the air containing 3000 ppm ammonia discharged from the dusting tank is sent from line 18 to catalyst column 19.
where it undergoes oxidative decomposition and has an ammonia content of 30
ppm and enters the heat exchanger 7 from the line 20 to warm the air sent to the aeration tank, and then from the line 21 to the line 2.
It enters the exhaust tower 23 together with the air from 2 and is also discharged into line 24 with an ammonia content of 5 ppm.
以上詳述したように、本発明方法によれば、従来BOD
,COD,SSの除去と、アンモニア態窒素の除去とを
別個に行っていた2つの技術を、■槽のみ(すなわち、
添付図面でいえば、1つのばっ気槽4のみ)で同時に行
うことができる。As detailed above, according to the method of the present invention, conventional BOD
, COD, SS and ammonia nitrogen were removed separately.
In the attached drawing, only one aeration tank 4) can be used at the same time.
添付図面は本発明の一実施態様を示すフローシ一トであ
る。The accompanying drawing is a flow sheet illustrating one embodiment of the invention.
Claims (1)
廃液中に空気を送りこんでばつ気し、好アルカリ性細菌
を繁殖させて活性汚泥化することにより、アンモニア態
窒素を除《と同時に化学的酸素要求化合物(COD)、
生物学的酸素要求化合物(BOD)および浮遊物質(S
S)を除くことを特徴とするアルカリ性廃液の処理方法
。1 Air is pumped into the alkaline waste liquid with a liquid temperature of 30 to 50°C and a pH of 9.5 to 11 to aerate it, and alkaliphilic bacteria are propagated to turn it into activated sludge, which removes ammonia nitrogen. oxygen demanding compounds (COD),
Biological oxygen demand compounds (BOD) and suspended solids (S
A method for treating alkaline waste liquid characterized by removing S).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP50055478A JPS5849320B2 (en) | 1975-05-13 | 1975-05-13 | alkaline |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP50055478A JPS5849320B2 (en) | 1975-05-13 | 1975-05-13 | alkaline |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS51132654A JPS51132654A (en) | 1976-11-17 |
JPS5849320B2 true JPS5849320B2 (en) | 1983-11-02 |
Family
ID=12999710
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP50055478A Expired JPS5849320B2 (en) | 1975-05-13 | 1975-05-13 | alkaline |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5849320B2 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2002028693A (en) * | 2000-07-14 | 2002-01-29 | Kurabo Ind Ltd | Method for treating alkaline wastewater |
-
1975
- 1975-05-13 JP JP50055478A patent/JPS5849320B2/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
JPS51132654A (en) | 1976-11-17 |
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