JPH0324280B2 - - Google Patents
Info
- Publication number
- JPH0324280B2 JPH0324280B2 JP58126580A JP12658083A JPH0324280B2 JP H0324280 B2 JPH0324280 B2 JP H0324280B2 JP 58126580 A JP58126580 A JP 58126580A JP 12658083 A JP12658083 A JP 12658083A JP H0324280 B2 JPH0324280 B2 JP H0324280B2
- Authority
- JP
- Japan
- Prior art keywords
- tank
- denitrification
- nitrification
- reaction
- concentration
- 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 - Lifetime
Links
- 238000006243 chemical reaction Methods 0.000 claims description 48
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 41
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 31
- 239000001301 oxygen Substances 0.000 claims description 31
- 229910052760 oxygen Inorganic materials 0.000 claims description 31
- 241000894006 Bacteria Species 0.000 claims description 22
- 229910052757 nitrogen Inorganic materials 0.000 claims description 20
- 239000007788 liquid Substances 0.000 claims description 19
- 238000000034 method Methods 0.000 claims description 15
- 239000002351 wastewater Substances 0.000 claims description 11
- 230000001546 nitrifying effect Effects 0.000 claims description 10
- 230000029058 respiratory gaseous exchange Effects 0.000 claims description 9
- 239000007789 gas Substances 0.000 claims description 6
- 229910017464 nitrogen compound Inorganic materials 0.000 claims description 6
- 150000002830 nitrogen compounds Chemical class 0.000 claims description 6
- 238000003756 stirring Methods 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 16
- 238000002474 experimental method Methods 0.000 description 13
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 6
- 229910052799 carbon Inorganic materials 0.000 description 6
- 238000005273 aeration Methods 0.000 description 5
- 230000007423 decrease Effects 0.000 description 5
- 239000010800 human waste Substances 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000010802 sludge Substances 0.000 description 3
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000000241 respiratory effect Effects 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000006228 supernatant Substances 0.000 description 2
- 238000004065 wastewater treatment Methods 0.000 description 2
- 238000013019 agitation Methods 0.000 description 1
- 230000001580 bacterial effect Effects 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 244000005700 microbiome Species 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
Landscapes
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
Description
〔発明の技術分野〕
本発明は、廃水中の無機性窒素を、生物学的内
生呼吸型脱窒反応を利用して除去する廃水の処理
方法に関する。
〔発明の技術的背景とその問題点〕
近来し尿等の窒素化合物を高濃度に含有する有
機性廃水を生物学的に処理する場合、無希釈のま
まで高負荷運転によりBOD、窒素の除去を行う
ことが一般化しつつある。この場合の窒素除去は
硝化反応と脱窒反応で行なわれる。硝化反応は廃
水中のNH4 +を溶存酸素の存在下で硝化菌により
NO2 -、あるいはNO3 -に酸化する反応のことで、
一般的には次式で表現される。
2NH4 +＋3O2→2NO2 -＋2H2O＋4H+
NH4 +＋2O2→NO3 -＋H2O＋2H+
こうして生成したNO2 -、NO3 -（以下NOxとよ
ぶ）は脱窒工程において廃水中の有機炭素源を還
元剤として、脱窒菌により還元されN2ガスとな
り除去される。
こうした硝化反応と脱窒反応を単一槽で同時に
実施する方法はすでに開発されている（特開昭53
−92551号公報、57−204294号公報）。ただ、これ
らの槽から流出水の無機性窒素としては20〜60
mg／残存しており、さらに高度に窒素除去する
場合、単一槽の後段に硝化槽と脱窒槽の設置が必
要となる。
次に第１図によつてその一例を説明する。
無希釈のし尿等の窒素化合物を高濃度に含む原
水１を高負荷反応槽２に流入させ、ここで窒素と
BODの大部分が除去される。（高負荷反応槽２の
流出液の水質は後述の表１に示す）高負荷反応槽
２からの流出液は、固液分離は行わず生物濃度
（MLSS）はその濃度を維持し硝化菌と脱窒菌を
存在させたまま次の硝化槽３に導入される。硝化
槽３では曝気撹拌により高負荷反応槽２からの流
出液中の硝化菌を利用してNH3の硝化が行われ
NH3は高度に除去され、BODの除去も同時に行
われる。次に硝化槽３からの流出液は脱窒槽４に
導かれる。脱窒槽４では、高負荷反応槽２からの
流出液中に存在するNOxおよび硝化槽３で生成
したNOxの脱窒が行われる。このとき液中の
BOD濃度は低くなつているから、原水中の有機
質炭素源を利用する脱窒は行われない。このた
め、メタノール等の有機質炭素源を添加するか或
いは高負荷反応槽２から分離されずに流出液中に
残存しているMLSS中の脱窒菌の内生呼吸作用を
利用して内生呼吸型脱窒反応を行わせる。この内
生呼吸型脱窒反応とは脱窒菌の構成成分自体を還
元剤とする脱窒反応であり、一般に内生呼吸にお
いても水中の溶存酸素を利用するが、水中の溶存
酸素が低下すれば、NOx中の酸素を利用して脱
窒反応が進行するものである。有機炭素源を添加
せずに内生呼吸型脱窒反応を行わせると、有機炭
素源添加に比べて反応速度が低下するが、MLSS
を高濃度に維持することにより実用的速度で脱窒
が行われる。このようにして脱窒された流出液
は、沈澱池５に導かれ、固液分離され、上澄液は
放流され汚泥６は高負荷反応槽２に返送される。
上述のように内生呼吸型脱窒反応による脱窒を
行うときは有機炭素源を供給することなく脱窒が
行われるという利点はあるが、これを実用的速度
で行わせるには脱窒槽４にMLSSを高濃度に維持
する必要があり、このため微生物の自己分解によ
り硝化槽３でせつかく除去したNH3濃度が脱窒
槽４で増加するという欠点がある。その一例とし
て高負荷反応槽２の流出液を回分方式でNH3を
硝化させた後に脱窒素実験を行つた結果を第２図
に示す。
実験の条件
MLSS；15000mg／
硝化工程溶存酸素濃度；２mg／
水温；30℃
この第２図によれば、硝化工程においては無機
性窒素の増加が認められ、脱窒素工程ではNH3
の増加が認められる。脱窒素工程でのNH3の増
加は高濃度のMLSSの自己分解によるものであ
る。なお硝化工程でもNH3が増加しているので
あるが硝化されるため無機性窒素の増加となつて
表われている。このため、この方法では硝化の効
率が悪く、十分に窒素除去が行なえない。
〔発明の目的〕
本発明は上述の問題点に鑑み高負荷反応槽で高
度にBOD、窒素が除去された流出液を単一の硝
化脱窒槽に導き、この硝化脱窒槽の溶存酸素濃度
を０〜0.5mg／に維持するように曝気撹拌する
ことにより生物学的硝化反応と内生呼吸型脱窒反
応とを同時に行わせ、高負荷反応槽の流出液中に
残存する無機性窒素（NH3、NO2、NO3）を高
度に除去しようとするものである。
〔発明の概要〕
本発明は、高負荷反応槽で窒素化合物を高濃度
に含有する有機性廃水を生物学的BOD除去、窒
素除去を施すことにより得られた硝化菌と脱窒菌
が共に存在する流出液を、単一の硝化脱窒槽に導
入し、この液中に酸素含有ガスを導入して撹拌し
液中の溶存酸素濃度を０〜0.5mg／に維持する
ことにより、液中の無機性窒素（NH3、NO2、
NO3）を生物学的硝化反応と生物学的内生呼吸
型脱窒反応とにより除去するものである。
〔発明の実施例〕
次に本発明の実施例を第３図について説明す
る。
２は窒素化合物を高度に含有する無希釈のし尿
等の廃水よりなる原水１が導入される高負荷反応
槽で、高度の酸素溶解能力を有する。槽２内には
よく順養された硝化菌、脱窒菌、BOD酸化菌か
らなる活性汚泥が高濃度に維持されており、槽２
内に供給される酸素によりNH3の酸化とBODの
酸化が行われる。またNH3の酸化により生じた
NOxは脱窒菌によりN2ガスとして除去されるが、
この際NOx中の酸素を利用したBOCの酸化も行
われる。このようにして窒素とBODの大部分が
除去される。
７は硝化脱窒槽で高負荷反応槽２から硝化菌と
脱窒菌を含む微生物が分離されない液（NH3−
Ｎとして20〜50mg／、無機性窒素として20〜60
mg／）が導入されこの液中に酸素含有ガスが吹
き込まれて曝気撹拌され、液中の溶存酸素濃度が
常に０〜0.5mg／となるよう制御され生物学的
硝化反応と生物学的内生呼吸型脱窒反応とが同時
に行われる。硝化反応と脱窒反応とを同時に進行
させる条件としては、液中の溶存酸素濃度る０〜
0.5mg／、好ましくは0.1〜0.3mg／に維持する
ことが必要である。溶存酸素濃度が0.3mg／以
上で内生呼吸型脱窒反応は遅くなりだし、0.5
mg／以上では殆んど認められない。また溶存酸
素が0.1mg／以下では硝化反応が遅くなりだす。
また溶存酸素の存在によりBODの除去も同時に
行われる。この硝化脱窒槽７の溶存酸素濃度を
0.1〜0.3mg／で運転した場合は、その処理水質
を従来法の硝化槽と脱窒槽よりなる２槽方式の処
理水質と比較すると、NH3濃度、BOD濃度は硝
化槽と略等しく、例えばNH3−N5mg／以下、
BOD20〜50mg／であり、NOx濃度は略脱窒槽
として等しい例えばNO2−N1mg／以下のもの
が得られる。
また、硝化脱窒槽７の液温は10〜40℃、PHは
6.0〜8.5に維持することが好ましい。水温が10℃
以下になると硝化菌、脱窒菌の活性が低下し、反
応速度が急に遅くなり、40℃以上になると、硝化
菌が死滅するようになるためである。さらにPHが
6.0以下になると硝化に必要なアルカリ度が低下
し硝化速度が遅くなり、PHが8.5以上になると一
般的に細菌の活性が低下するため反応速度が低下
する。したがつてPHは6.0〜8.85の範囲が適当で
ある。
５は沈澱池で、硝化脱窒槽７からの流出液が導
入され、固液分離されて上澄水は処理水として放
流され、汚泥６は前記高負荷反応槽２へ返送され
る。
〔発明の効果〕
本発明によれば、高負荷反応槽で窒素化合物を
高濃度に含有する有機性廃水に生物学的BOD除
去、窒素除去を施すことにより得られた硝化菌と
脱窒菌が共存する流出液を、単一の硝化脱窒槽に
導き、液中に酸素含有ガスを導いて撹拌し水中の
溶存酸素濃度を０〜0.5mg／に維持することに
より、液中の無機性窒素を生物学的硝化反応と生
物学的内生呼吸型脱窒反応とにより除去するため
硝化菌と脱窒菌の共存により単一槽内で生物学的
硝化反応と生物学的内生呼吸型脱窒反応が行われ
液中の溶存酸素濃度を０mg／以上にして硝化反
応を進行させかつ0.5mg／以下に維持して内生
呼吸型脱窒反応を同時に進行させることにより
BOD、NOx、NH3の高度な除去を行うことがで
きる。さらに硝化と脱窒を単一槽で行うため設備
が簡単化し装置の保守管理も容易となるものであ
る。
〔発明の実験例〕
次に本発明の実験例を説明する。
１ 実験の装置
[Technical Field of the Invention] The present invention relates to a wastewater treatment method that removes inorganic nitrogen from wastewater using a biological endogenous respiration type denitrification reaction. [Technical background of the invention and its problems] Recently, when organic wastewater containing a high concentration of nitrogen compounds such as human waste is biologically treated, BOD and nitrogen can be removed by high-load operation without dilution. It is becoming common to do this. Nitrogen removal in this case is performed by nitrification and denitrification reactions. Nitrification reaction converts NH4 + in wastewater by nitrifying bacteria in the presence of dissolved oxygen.
A reaction that oxidizes to NO 2 - or NO 3 - .
Generally, it is expressed by the following formula. 2NH 4 + +3O 2 →2NO 2 - +2H 2 O+4H + NH 4 + +2O 2 →NO 3 - +H 2 O+2H +NO 2 - and NO 3 - (hereinafter referred to as NO x ) generated in this way are removed from wastewater during the denitrification process. Using an organic carbon source as a reducing agent, denitrification bacteria reduce the nitrogen gas and remove it as N2 gas. A method for carrying out such nitrification and denitrification reactions simultaneously in a single tank has already been developed (Japanese Patent Application Laid-Open No. 53
-92551 publication, 57-204294 publication). However, the amount of inorganic nitrogen in the water flowing out from these tanks is 20 to 60%.
mg/remains, and if nitrogen is to be removed to a higher degree, it is necessary to install a nitrification tank and a denitrification tank after the single tank. Next, an example will be explained with reference to FIG. Raw water 1 containing a high concentration of nitrogen compounds such as undiluted human waste flows into a high-load reaction tank 2, where it is treated with nitrogen.
Most of the BOD is removed. (The water quality of the effluent from the high-load reaction tank 2 is shown in Table 1 below.) The effluent from the high-load reaction tank 2 is not subjected to solid-liquid separation, and the biological concentration (MLSS) is maintained at the same concentration. The denitrifying bacteria are introduced into the next nitrification tank 3 with the denitrifying bacteria still present. In the nitrification tank 3, nitrification of NH 3 is performed using nitrifying bacteria in the effluent from the high-load reaction tank 2 through aeration and agitation.
NH3 is highly removed and BOD is removed at the same time. Next, the effluent from the nitrification tank 3 is led to the denitrification tank 4. In the denitrification tank 4, NO x present in the effluent from the high-load reaction tank 2 and NO x generated in the nitrification tank 3 are denitrified. At this time, in the liquid
Since the BOD concentration is low, denitrification using organic carbon sources in the raw water is not performed. Therefore, by adding an organic carbon source such as methanol or by utilizing the endogenous respiration of denitrifying bacteria in the MLSS that remains in the effluent without being separated from the high-load reaction tank 2, endogenous respiration can be performed. Allow denitrification reaction to occur. This endogenous respiration-type denitrification reaction is a denitrification reaction that uses the constituent components of denitrifying bacteria itself as a reducing agent.Generally, endogenous respiration also uses dissolved oxygen in water, but if dissolved oxygen in water decreases, , the denitrification reaction proceeds using oxygen in NO x . When an endogenous respiration type denitrification reaction is performed without adding an organic carbon source, the reaction rate is lower than when an organic carbon source is added, but MLSS
By maintaining a high concentration of nitrogen, denitrification is carried out at a practical rate. The effluent denitrified in this way is led to the sedimentation tank 5, where it is separated into solid and liquid, the supernatant liquid is discharged, and the sludge 6 is returned to the high-load reaction tank 2. As mentioned above, denitrification by endogenous respiration type denitrification reaction has the advantage that denitrification is performed without supplying an organic carbon source, but in order to perform this at a practical rate, denitrification tank 4 is required. It is necessary to maintain the MLSS at a high concentration, which has the drawback that the NH 3 concentration painstakingly removed in the nitrification tank 3 increases in the denitrification tank 4 due to self-decomposition of microorganisms. As an example, FIG. 2 shows the results of a denitrification experiment conducted after nitrifying NH 3 from the effluent from the high-load reaction tank 2 in a batch manner. Experimental conditions MLSS: 15000mg/Nitrification process Dissolved oxygen concentration: 2mg/Water temperature: 30℃ According to this figure 2, an increase in inorganic nitrogen is observed in the nitrification process, and NH3 in the denitrification process.
An increase was observed. The increase in NH 3 during the denitrification process is due to the autodecomposition of high concentrations of MLSS. Note that NH 3 is also increased in the nitrification process, but because it is nitrified, it appears as an increase in inorganic nitrogen. For this reason, this method has poor nitrification efficiency and cannot sufficiently remove nitrogen. [Object of the Invention] In view of the above-mentioned problems, the present invention introduces the effluent from which BOD and nitrogen have been highly removed in a high-load reaction tank to a single nitrification-denitrification tank, and reduces the dissolved oxygen concentration in this nitrification-denitrification tank to 0. Biological nitrification and endogenous respiration-type denitrification reactions are carried out simultaneously by aeration and stirring to maintain a concentration of ~0.5 mg/day, and inorganic nitrogen (NH 3 ) remaining in the effluent of the high-load reaction tank is , NO 2 , NO 3 ). [Summary of the Invention] The present invention is a method of treating organic wastewater containing a high concentration of nitrogen compounds with biological BOD removal and nitrogen removal in a high-load reaction tank, in which both nitrifying bacteria and denitrifying bacteria exist. The effluent is introduced into a single nitrification and denitrification tank, and an oxygen-containing gas is introduced into the liquid and stirred to maintain the dissolved oxygen concentration in the liquid at 0 to 0.5mg/. Nitrogen (NH 3 , NO 2 ,
NO 3 ) is removed by a biological nitrification reaction and a biological endogenous respiration-type denitrification reaction. [Embodiment of the Invention] Next, an embodiment of the present invention will be described with reference to FIG. Reference numeral 2 denotes a high-load reaction tank into which raw water 1 consisting of undiluted waste water such as human waste containing a high degree of nitrogen compounds is introduced, and has a high oxygen dissolving ability. In tank 2, activated sludge consisting of well-acclimated nitrifying bacteria, denitrifying bacteria, and BOD oxidizing bacteria is maintained at a high concentration.
The oxygen supplied inside oxidizes NH 3 and BOD. Also, the oxidation of NH 3
NO x is removed as N 2 gas by denitrifying bacteria,
At this time, BOC is also oxidized using oxygen in NO x . In this way most of the nitrogen and BOD are removed. 7 is a nitrification-denitrification tank in which the liquid (NH 3 −
20 to 50 mg/as N, 20 to 60 as inorganic nitrogen
mg/) is introduced into the liquid, oxygen-containing gas is blown into the liquid, aeration is agitated, and the dissolved oxygen concentration in the liquid is always controlled to be 0 to 0.5 mg/. A respiratory denitrification reaction is carried out simultaneously. The conditions for simultaneous progress of nitrification and denitrification reactions are as follows: the dissolved oxygen concentration in the liquid is 0~
It is necessary to maintain it at 0.5 mg/, preferably 0.1-0.3 mg/. When the dissolved oxygen concentration is 0.3 mg/ or more, the endogenous respiration type denitrification reaction starts to slow down, and the concentration of 0.5
It is hardly recognized at mg/ or more. Furthermore, when dissolved oxygen is less than 0.1 mg/day, the nitrification reaction begins to slow down.
Also, BOD is removed at the same time due to the presence of dissolved oxygen. The dissolved oxygen concentration in this nitrification and denitrification tank 7 is
When operating at 0.1 to 0.3mg/, the treated water quality is compared with the treated water quality of the conventional two-tank system consisting of a nitrification tank and a denitrification tank, and the NH 3 concentration and BOD concentration are approximately the same as the nitrification tank. 3 −N5mg/or less,
The BOD is 20 to 50 mg/, and the NO x concentration is approximately equal to that of a denitrification tank, for example, NO 2 -N 1 mg/or less. In addition, the liquid temperature in the nitrification and denitrification tank 7 is 10 to 40℃, and the pH is
It is preferable to maintain it between 6.0 and 8.5. Water temperature is 10℃
This is because when the temperature is below 40°C, the activity of nitrifying bacteria and denitrifying bacteria decreases, and the reaction rate suddenly slows down, and when the temperature exceeds 40°C, nitrifying bacteria become extinct. Furthermore, the PH
When the pH is below 6.0, the alkalinity required for nitrification decreases and the nitrification rate slows down, and when the pH becomes 8.5 or above, the reaction rate generally decreases due to a decrease in bacterial activity. Therefore, a suitable pH range is 6.0 to 8.85. Reference numeral 5 denotes a sedimentation tank, into which the effluent from the nitrification and denitrification tank 7 is introduced, solid-liquid separation is performed, and the supernatant water is discharged as treated water, and the sludge 6 is returned to the high-load reaction tank 2. [Effects of the Invention] According to the present invention, nitrifying bacteria and denitrifying bacteria coexist by performing biological BOD removal and nitrogen removal on organic wastewater containing a high concentration of nitrogen compounds in a high-load reaction tank. The effluent is introduced into a single nitrification-denitrification tank, and oxygen-containing gas is introduced into the liquid and stirred to maintain the dissolved oxygen concentration in the water at 0 to 0.5mg/. Biological nitrification and biological endogenous respiratory denitrification reactions occur in a single tank due to the coexistence of nitrifying bacteria and denitrifying bacteria. By increasing the dissolved oxygen concentration in the liquid to 0 mg/ or more to allow the nitrification reaction to proceed, and maintaining it to 0.5 mg/ or less to allow the endogenous respiration-type denitrification reaction to proceed at the same time.
A high level of removal of BOD, NO x and NH 3 can be performed. Furthermore, since nitrification and denitrification are carried out in a single tank, the equipment is simplified and maintenance of the equipment is also easier. [Experimental Examples of the Invention] Next, experimental examples of the present invention will be described. 1 Experimental equipment
【表】
２ 試料
原水として、処理水量15m3／日でし尿の無希
釈処理を行つている実設備の高負荷反応槽内の
反応液を用いた。反応液の性状は下記表１のと
おりである。[Table] 2 Samples As the raw water, we used the reaction liquid in a high-load reaction tank of an actual facility that performs undiluted treatment of human waste with a treated water volume of 15 m 3 /day. The properties of the reaction solution are shown in Table 1 below.
【表】
３ 実験の方法
実験１；硝化槽と脱窒槽を用いて従来の方法に
より硝化槽で曝気による硝化反応、脱窒槽で
内生呼吸型脱窒反応を行わせた。
実験２；
実験３；
実験４；脱窒槽を単独で用い曝気による
硝化反応と内生呼吸型脱窒反応
を同時に行わせた。
各実験の運転条件は下記表２の通りである。[Table] 3 Experimental method Experiment 1: Using a nitrification tank and a denitrification tank, a nitrification reaction by aeration was carried out in the nitrification tank and an endogenous respiration-type denitrification reaction was carried out in the denitrification tank using the conventional method. Experiment 2; Experiment 3; Experiment 4: A denitrification tank was used alone to simultaneously carry out the nitrification reaction by aeration and the endogenous respiration type denitrification reaction. The operating conditions for each experiment are shown in Table 2 below.
【表】
＊ 実験１の溶存酸素濃度は硝化槽の溶存酸
素濃度を示す。
４ 実験の結果
実験の結果は下記表３の通りである。[Table] * The dissolved oxygen concentration in Experiment 1 indicates the dissolved oxygen concentration in the nitrification tank.
4 Experimental Results The experimental results are shown in Table 3 below.
【表】
上記表３より、従来法である実験１は、脱窒槽
では硝化槽で生成したNOxは除去されているが、
硝化槽で除去されたBOD、NH3が増加している。
実験２〜４は何れも単一の脱窒槽で夫々異なる溶
存酸素濃度で硝化と脱窒を同時に行つたものであ
るが、実験２は、溶存酸素濃度を０mg／に維持
すると、BOD、NOxは除去されるが硝化が完全
でなく、NH3が雑存することを示し、実験３は、
溶存酸素濃度が0.1〜0.3mg／に維持すると、
BOD、NH3、NOxが高度に除去されることを示
し、実験４は、溶存酸素濃度を0.5〜0.8mg／に
維持すると、BOD、NH3は除去されるが、脱窒
が完全でなくNOxが残存することを示している。
したがつて本発明の方法で溶存酸素濃度は、特
に0.1〜0.3mg／が好適であることがわかる。[Table] From Table 3 above, in Experiment 1, which is the conventional method, NO x generated in the nitrification tank was removed in the denitrification tank, but
BOD and NH3 removed in the nitrification tank are increasing.
In Experiments 2 to 4, nitrification and denitrification were performed simultaneously at different dissolved oxygen concentrations in a single denitrification tank, but in Experiment 2, when the dissolved oxygen concentration was maintained at 0 mg/, BOD, NO x is removed, but nitrification is not complete, indicating that NH3 is present, and Experiment 3 shows that
When the dissolved oxygen concentration is maintained at 0.1 to 0.3 mg/
Experiment 4 showed that BOD, NH 3 and NO x were removed to a high degree, and when the dissolved oxygen concentration was maintained at 0.5 to 0.8 mg/, BOD and NH 3 were removed, but denitrification was not complete. This indicates that NO x remains. Therefore, it can be seen that in the method of the present invention, the dissolved oxygen concentration is particularly preferably 0.1 to 0.3 mg/.
第１図は従来の廃水処理方法の工程説明図、第
２図は同上工程における無機性窒素の濃度と反応
時間の関係図、第３図は本発明の一実施例を示す
工程説明図である。
２……高負荷反応槽、７……硝化脱窒槽。
Fig. 1 is a process explanatory diagram of a conventional wastewater treatment method, Fig. 2 is a diagram showing the relationship between the concentration of inorganic nitrogen and reaction time in the same process, and Fig. 3 is a process explanatory diagram showing an embodiment of the present invention. . 2... High load reaction tank, 7... Nitrification denitrification tank.
Claims (1)
る有機性廃水に生物学的BOD除去、窒素除去を
施すことにより得られた硝化菌と脱窒菌が共存す
る流出液を、単一の硝化脱窒槽に導き、液中に酸
素含有ガスを導いて撹拌し液中の溶存酸素濃度を
０〜0.5mg／に維持することにより、液中の無
機性窒素を生物学的硝化反応と生物学的内生呼吸
型脱窒反応とにより除去することを特徴とする廃
水の処理方法。 ２ 硝化脱窒槽の液中の溶存酸素濃度を0.1〜0.3
mg／に維持することを特徴とする特許請求の範
囲第１項記載の廃水の処理方法。[Claims] 1. The effluent in which nitrifying bacteria and denitrifying bacteria coexist is obtained by biologically removing BOD and nitrogen from organic wastewater containing a high concentration of nitrogen compounds in a high-load reaction tank. The inorganic nitrogen in the liquid is biologically nitrified by introducing oxygen-containing gas into the liquid and stirring it to maintain the dissolved oxygen concentration in the liquid at 0 to 0.5mg/. A method for treating wastewater characterized by removal by a reaction and a biological endogenous respiration type denitrification reaction. 2 Set the dissolved oxygen concentration in the liquid in the nitrification and denitrification tank to 0.1 to 0.3.
The method for treating wastewater according to claim 1, characterized in that the wastewater is maintained at a concentration of mg/mg/ml.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12658083A JPS6019098A (en) | 1983-07-12 | 1983-07-12 | Treatment of waste water |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12658083A JPS6019098A (en) | 1983-07-12 | 1983-07-12 | Treatment of waste water |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6019098A JPS6019098A (en) | 1985-01-31 |
| JPH0324280B2 true JPH0324280B2 (en) | 1991-04-02 |
Family
ID=14938685
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12658083A Granted JPS6019098A (en) | 1983-07-12 | 1983-07-12 | Treatment of waste water |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6019098A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6373629B2 (en) * | 2014-04-25 | 2018-08-15 | 株式会社日立製作所 | Water treatment monitoring and control system, water treatment system having the same, and water treatment method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5724699A (en) * | 1980-07-17 | 1982-02-09 | Mitsubishi Heavy Ind Ltd | Disposal of highly concentrated waste liquid |
| JPS57204294A (en) * | 1981-06-10 | 1982-12-14 | Kubota Ltd | Denitrification of water |
-
1983
- 1983-07-12 JP JP12658083A patent/JPS6019098A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5724699A (en) * | 1980-07-17 | 1982-02-09 | Mitsubishi Heavy Ind Ltd | Disposal of highly concentrated waste liquid |
| JPS57204294A (en) * | 1981-06-10 | 1982-12-14 | Kubota Ltd | Denitrification of water |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6019098A (en) | 1985-01-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2003053387A (en) | Method for biologically removing nitrogen | |
| JP4649911B2 (en) | Treatment of organic matter and nitrogen-containing wastewater | |
| JP4882175B2 (en) | Nitrification method | |
| JP2003126887A (en) | Method and device for treating water containing phosphorus and ammonia | |
| JP4302341B2 (en) | Biological nitrogen removal method and apparatus | |
| JP2006272172A (en) | Method and apparatus for biologically treating nitrogen-containing water | |
| JP4957229B2 (en) | Waste water treatment method and waste water treatment apparatus | |
| JP4320515B2 (en) | Method for treating raw water containing phosphorus and ammonia nitrogen | |
| JP4570550B2 (en) | Nitrogen removal method and apparatus for high concentration organic wastewater | |
| JP3377346B2 (en) | Organic wastewater treatment method and apparatus | |
| KR100470350B1 (en) | Method for disposing of livestock waste water | |
| JPH0324280B2 (en) | ||
| JP3358388B2 (en) | Treatment method for selenium-containing water | |
| JP3944981B2 (en) | Method for treating selenium and nitrogen-containing water | |
| JP3837757B2 (en) | Method for treating selenium-containing water | |
| JP2001259688A (en) | Waste liquid treating method | |
| JP3358389B2 (en) | Treatment method for selenium-containing water | |
| JPH0994596A (en) | Removal and recovery of phosphorus from organic sewage | |
| JPH09122679A (en) | Method for processing organic waste water and its apparatus | |
| JPH03275196A (en) | Nitrous acid type nitrifying and denitrifying treatment device | |
| JP3837763B2 (en) | Method for treating selenium-containing water | |
| JP3639679B2 (en) | Nitrogen removal method of wastewater by modified activated sludge circulation method | |
| JPS63291698A (en) | Biological denitrification of waste water | |
| JPH09290290A (en) | Treatment of coke-oven gas liquor | |
| JP2002273476A (en) | Treatment of waste water containing high-concentration nitrogen |