JPS5998800A - Biological treatment of waste water containing organic substance - Google Patents

Abstract

PURPOSE:To perform the efficient biological treatment of organic sludge, while making equipment small in size, by aerating separately precipitated sludge in a state mixed with anaerobic sludge, and returning the mixed sludge to the inlet of an intensive aeration tank and an aerobic tank. CONSTITUTION:Waste water a containing organic substance, e.g. waste water in processing marine or agricultural products, is collected in a conditioner tank 1, and its predetermined amount is continuously supplied to an anaerobic tank 2. Thereafter, treatment is sequentially performed in the order of an intensive aeration tank 3, a separator 4, an aerobic tank 5 and a separate precipitation tank 6. Aerobic sludge separately precipitated in the separate precipitation tank 6 is mixed with anaerobic sludge from the anaerobic tank 3 in a reaeration tank 7. The aerated matter is returned to the inlet of the intensive aeration tank 3 and also returned to the aerobic tank 5 to biologically treat the waste water. The waste water is returned to the aerobic tank 5 and biologically treated therein. In the anaerobic tank 2, the waste water is aerated with air introduced through a blower 8. Aerobes are mainly composed of genus zoogloea, and ferment, etc. may be included.

Description

【発明の詳細な説明】 この発明は水産加工廃水、人畜し原廃水、農産加工廃水
などの有機性物質を含む廃水の生物学的処理方法に関す
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a biological treatment method for wastewater containing organic substances, such as fishery processing wastewater, human and livestock processing wastewater, and agricultural processing wastewater.

周知のように、この種の廃水の生物学的処理方法として
は、第１図に示すような工程からなる活性汚泥法が従前
から使用されている。この方法は、廃水を一旦開接種Ａ
に溜めて、必要に応じて液性の均一化、栄養源の添加、
ＰＨ調節などの作業を施した後、その一定量を連続的に
曝気槽Ｂへ給水する。この曝気ｆｌＢに一定時間滞留中
に、廃水の有機性物質が、送風機Ｃから送り込まれる空
気により活発に活動している好気性細菌によって酸化分
解されて、活性ｌη泥（フロック）が形成され、この活
性汚泥と共に廃水が沈降分離槽りに送られる。そして、
沈降分離槽りにおいても、一定時間滞留させて、活性汚
泥と上澄液を分離させ、上澄液は処理水として放流され
る。一方、沈降した活性汚泥は、汚泥ポンプ已によって
一部を曝気槽Ｂへ返送して循環使用し曝気槽Ｂ内の活性
汚泥濃度を保持して、好気性細菌による酸化分解に役立
たせている。曝気槽Ｂへ返送した残余の活性汚泥は余剰
汚泥として、前記循環系外へ引き出して汚泥脱水機Ｆに
より液体と固体に分離され、固体は埋立、投棄等の処分
がなされる。As is well known, as a biological treatment method for this type of wastewater, the activated sludge method, which consists of the steps shown in FIG. 1, has been used for a long time. In this method, wastewater is first opened and inoculated with A.
to homogenize the liquid and add nutrients as necessary.
After performing work such as pH adjustment, a certain amount of water is continuously supplied to the aeration tank B. While remaining in this aeration flB for a certain period of time, organic substances in the wastewater are oxidized and decomposed by aerobic bacteria that are actively active by the air sent in from the blower C, forming activated lη mud (floc). Wastewater is sent to a settling tank along with activated sludge. and,
In the sedimentation separation tank, the activated sludge is allowed to remain for a certain period of time to separate the activated sludge from the supernatant, and the supernatant is discharged as treated water. On the other hand, a part of the settled activated sludge is returned to the aeration tank B by the sludge pump and used for circulation, and the activated sludge concentration in the aeration tank B is maintained to be useful for oxidative decomposition by aerobic bacteria. The remaining activated sludge returned to the aeration tank B is drawn out of the circulation system as surplus sludge and separated into liquid and solid by the sludge dehydrator F, and the solid is disposed of by landfilling, dumping, etc.

このような従来の活性汚泥法においては、廃水のＢ　Ｏ
Ｄ　？５度が高い場合には、好気性細菌による酸化分解
が進行しないために、所定のＢＯＤ濃度以上の廃水を活
性汚泥法で処理する場合には、稀釈水を多量に加えてＢ
ＯＤ濃度を低下させる必要がある。そして、この稀釈水
による廃水量の増加に伴い、曝気槽Ｂ等が大型化し運転
管理が複雑になるのに加えて、稀釈水の給水施設等の諸
経費の増加、さらには曝気槽Ｂにおける曝気量の増大に
伴う送風機Ｃの動力費の増加などの種々の欠点を伴なっ
ている。In such a conventional activated sludge method, wastewater B O
D? If the temperature is high, oxidative decomposition by aerobic bacteria will not proceed, so when treating wastewater with a BOD concentration higher than a specified level using the activated sludge method, add a large amount of diluted water to the BOD.
It is necessary to reduce the OD concentration. As the amount of wastewater due to this diluted water increases, aeration tank B etc. becomes larger and operation management becomes more complicated. This is accompanied by various drawbacks such as an increase in the power cost of the blower C as the volume increases.

この発明は上記事情に鑑みてなされたものであって、廃
水のＢｏＤｎ度いがんにががわらず、極めて効率良く処
理することにより運転経費の軽減化、装置の小型化、運
転管理の単純化を図ることを目的とし、その特徴とする
ところは、第１の発明においては、調整槽から送られる
廃水を嫌気槽において、通性嫌気性細菌を含む嫌気性細
菌が顕在化した嫌気性汚泥状態を維持するのに適した曝
気量で曝気した後に、沈降分離槽から返送される好気性
汚泥及び前記嫌気槽からの嫌気性汚泥を再曝気槽に望め
て曝気して好気性汚泥の状態としたものを、前記嫌気槽
からの嫌気性汚泥と混合凝集し、強拍気槽で強曝気して
好気的状態とした後に、分離装置で汚泥を生育させ、こ
の汚泥は固液分離して固体部分を系外へ排出し、液体部
分は沈降分離槽から返送される好気性汚泥と混合して好
気槽でズーグレア（Ｚｏｏｇｌｏｅａ）尿細菌を含む好
気性細菌が活発化した好気性汚泥を生成するように曝気
した後、沈降分Ａｆｔ槽で沈降分離し上澄液を処理水と
して系外へ排出し、沈降した好気性汚泥を前記のように
、この廃水処理循環系内へ分配返送する廃水処理循環系
を形成したところにあり、第２の発明においては、第１
の発明における沈降分離槽よりの好気性汚泥を嫌気槽へ
も返送させるところにある。This invention was made in view of the above circumstances, and aims to reduce operating costs, downsize the equipment, and simplify operation management by treating wastewater extremely efficiently regardless of the BoDn degree. In the first invention, the wastewater sent from the adjustment tank is kept in an anaerobic sludge state in which anaerobic bacteria including facultative anaerobic bacteria are exposed in the anaerobic tank. After aerating at an aeration amount suitable for The sludge is mixed and flocculated with the anaerobic sludge from the anaerobic tank, and after being strongly aerated in the strong air tank to create an aerobic state, the sludge is grown in a separator, and this sludge is separated into solid and liquid to remove the solid part. It is discharged outside the system, and the liquid portion is mixed with aerobic sludge returned from the sedimentation separation tank to produce aerobic sludge in which aerobic bacteria including Zoogloea urine bacteria are activated in the aerobic tank. After aeration, a wastewater treatment circulation system that separates the sediment by sedimentation in the sedimentation Aft tank, discharges the supernatant liquid outside the system as treated water, and distributes and returns the settled aerobic sludge to the wastewater treatment circulation system as described above. In the second invention, the first
In the invention, aerobic sludge from the settling tank is also returned to the anaerobic tank.

この第１の発明を第２図を参照しつつ以下詳細に説明す
る。This first invention will be explained in detail below with reference to FIG.

この第１の発明は、廃水を調整槽１から嫌気槽２、強拍
気槽３、分離装置４、好気槽５、沈降分）亜種６及び沈
降分離槽６で沈降分離した好気性汚泥を再曝気槽７で嫌
気槽２からの嫌気性ｌη泥と混合して曝気したものを強
拍気槽３の入口へ返送させる共に好気槽５へも返送させ
る廃水処理循環系で生物学的に処理するものである。This first invention provides aerobic sludge obtained by separating wastewater from a regulating tank 1 through an anaerobic tank 2, a strong aerobic tank 3, a separator 4, an aerobic tank 5, a sedimentation subspecies 6, and a sedimentation separation tank 6. is mixed with anaerobic lη mud from the anaerobic tank 2 in the re-aeration tank 7, and the aerated mixture is returned to the inlet of the strong aeration tank 3 and also returned to the aerobic tank 5. It is processed accordingly.

この廃水処理循環系で作用する細菌のうち、好気性細菌
としてはズーグレア（Ｚｏｏｇｌｏｅａ）属が主体で、
その他酵母等も含まれ、嫌気性細菌とじては一部好気的
性質を有する通性嫌気性細菌、例えば、乳酸菌（Ｌａｃ
ｔｏｂａｃｉｌｌｕｓ　）属、ペディオコッカス（Ｐｅ
ｄｉｏｃｏｃｃｕｓ　）属、ストレゾ１−コツカス（Ｓ
ｔ、ｒｅｐｔｏｃｏｃｃｕｓ　）属、バチルス（Ｂａｃ
ｉｌｌｕｓ）属等に属する細菌が必須で、その他偏性嫌
気性細菌も含まれてもよい。これらあ好気性細菌及び嫌
気性細菌は廃水処理循環系の運転開始前に該系の中にあ
らかじめ投入おくことにより以後は該系の中で自然増殖
したものが使用される。Among the bacteria that act in this wastewater treatment circulation system, the main aerobic bacteria are the Zoogloea genus.
Other yeasts are also included, and anaerobic bacteria include facultative anaerobic bacteria that have some aerobic properties, such as lactic acid bacteria (Lac
tobacillus), Pediococcus (Pe
diococcus), Streso1-coccus (S
T, reptococcus) genus, Bacillus
Bacteria belonging to the genus Illus and the like are essential, and other obligate anaerobic bacteria may also be included. By introducing these aerobic bacteria and anaerobic bacteria into the wastewater treatment circulation system before the system starts operating, the bacteria that have grown naturally in the system can be used thereafter.

廃水は、水産加工廃水、畜産し原廃水、農産加工廃水、
その他の有機性物質を含む廃水であればその種類を問わ
ずにすべてこの発明方法で処理することができる。Wastewater includes fishery processing wastewater, raw livestock wastewater, agricultural processing wastewater,
Any type of wastewater containing other organic substances can be treated by the method of the present invention.

この廃水はまず調整槽１に築められ、ここで必要に応じ
て液性の均一化、栄養源の添加、ＰＨ調節などの作業が
行われる。そして、所定時間滞留させた後に、一定量が
連続的に嫌気槽２へ給水される。This wastewater is first collected in an adjustment tank 1, where operations such as equalization of liquid properties, addition of nutrients, and pH adjustment are performed as necessary. After the water has been retained for a predetermined period of time, a certain amount of water is continuously supplied to the anaerobic tank 2.

嫌気槽２においては、前記調整槽１から送られる廃水が
送風機８から送り込まれる空気によって曝気される。こ
の曝気は、廃水を弱く攪拌する目的と、嫌気性細菌の主
体をなす通性嫌気性細菌を顕在化させるため廃水中に溶
存酸素を微量に提供する目的のためであるから、単位汚
濁物質当りの曝気量は従来の活性汚泥法の曝気槽におけ
る曝気量の通常約１０分の１以下の弱い曝気でよいこと
が経験的、実験的に判明している。これより多い量の曝
気を行うと、混合液の攪拌は十分に行われるものの嫌気
性細菌が潜在化して曝気の目的に反することとなるため
である。このような条件に合致した曝気を行うことによ
り、嫌気槽２内においては、嫌気性細菌が顕在化した嫌
気性汚泥が生息している状態が維持される。In the anaerobic tank 2, the wastewater sent from the adjustment tank 1 is aerated with air sent from the blower 8. This aeration is for the purpose of stirring the wastewater weakly and providing a small amount of dissolved oxygen in the wastewater in order to bring out facultative anaerobic bacteria, which are the main group of anaerobic bacteria. It has been empirically and experimentally found that a weak aeration amount of about one-tenth or less of the aeration amount in the aeration tank of the conventional activated sludge method is sufficient. This is because if a larger amount of aeration is performed, although the mixed liquid will be sufficiently stirred, anaerobic bacteria will become latent, which will defeat the purpose of aeration. By performing aeration that meets these conditions, a state in which anaerobic sludge in which anaerobic bacteria are exposed is maintained in the anaerobic tank 2.

尚、前記調整槽１と嫌気槽２は廃水の性質あるいは諸般
の事情により調整槽１と嫌気槽２を一つにまとめてこれ
ら２つの槽１．２を兼ねる調整嫌気槽とすることができ
るが、これはこの発明方法の技術的範囲に含まれるもの
である。Incidentally, depending on the nature of the wastewater or various circumstances, the regulating tank 1 and anaerobic tank 2 may be combined into one regulating anaerobic tank that also serves as these two tanks 1.2. , which is included in the technical scope of the method of this invention.

再曝気槽７においては、前記嫌気槽２供給される嫌気性
汚泥と沈降分離槽６から汚泥ポンプ９により返送される
好気性ｌη泥が投入されて送風機８からの空気により眠
気されて、全体としてズーグレア（Ｚｏｏｇｌｏｅａ）
属細菌を含む好気性細菌が活発化した好気性汚泥が生成
される。この再曝気槽７　　　・を設りた理由は、廃水
処理循環系における廃水の浄化作用が促進されることに
より、沈降分離槽６において生成される好気性汚泥の濃
度が低くなって、嫌気槽２からの嫌気性汚泥と混合させ
た際に、汚泥が生成しにくくなるので、嫌気槽２からの
嫌気性汚泥を含む廃水と共に曝気して好気性汚泥を増量
させるためである。In the reaeration tank 7, the anaerobic sludge supplied to the anaerobic tank 2 and the aerobic lη sludge returned from the sedimentation separation tank 6 by the sludge pump 9 are put into the re-aeration tank 7, and are made drowsy by the air from the blower 8. Zoogloea
Aerobic sludge is produced in which aerobic bacteria including bacteria of the genus are activated. The reason for providing this re-aeration tank 7 is that by promoting the purification effect of wastewater in the wastewater treatment circulation system, the concentration of aerobic sludge produced in the sedimentation separation tank 6 is lowered, and the anaerobic tank 2 This is because sludge is difficult to generate when mixed with anaerobic sludge from the anaerobic tank 2, so the amount of aerobic sludge is increased by aeration together with the wastewater containing anaerobic sludge from the anaerobic tank 2.

強拍気槽３においては、前記嫌気槽２から供給される嫌
気性汚泥と前記再曝気槽７からのズーグレア（Ｚｏｏｇ
ｌｏｅａ）属細菌を含む好気性汚泥が混合投入される。In the strong aeration tank 3, anaerobic sludge supplied from the anaerobic tank 2 and zooglare from the reaeration tank 7 are mixed.
Aerobic sludge containing bacteria of the genus Loea is mixed and input.

この両者の投入量は固形物濃度で等量か好気性汚泥が少
し多い目に投入される。この２つの種類の異なる汚泥は
それぞれ相反する物理化学的性質を有しており、これら
相反する物理化学的性質のうち、クーロン力、ファンデ
ルワールス力による好気性汚泥と嫌気性汚泥との親和性
の増大、並びに２つの汚泥間ににけるある種の高分子間
結合反応の形成及び好気性細菌により形成された粘膜に
よる粘着力などの相乗効果により、２つの汚泥間におけ
る強固な凝集力がもたらされる。The amounts of both are equal in terms of solids concentration, or the amount of aerobic sludge is slightly larger. These two different types of sludge have contradictory physicochemical properties, and among these contradictory physicochemical properties, the affinity between aerobic sludge and anaerobic sludge due to Coulomb force and van der Waals force The strong cohesive force between the two sludges is brought about by synergistic effects such as an increase in the amount of sludge, the formation of a certain type of polymer bonding reaction between the two sludges, and the adhesive force due to the mucous membrane formed by aerobic bacteria. It will be done.

この強固な凝集力並びに凝集の進行に伴う熔解成分の取
り込み効果によって、好気性細菌と嫌気性細菌が共に顕
在化した新たな汚泥が生成されると共に、廃水゛の浄化
作用が促進されるのである。ちなみに、同一廃水から生
成された好気性汚泥と嫌気性汚泥は、上記のような強固
な凝集力を有するが、これに反して、異った廃水から生
成された好気性汚泥と嫌気性汚泥との間には、はとんど
凝集力が生しないことが実験的に判明している。このこ
とば、耐染反応が、単にクーロン力、ファンデルワール
ス力にのみによるものではなく、ある種の高分子間結合
反応の存在を示すものである。嫌気性細菌としては、前
記した通性嫌気性細菌の添加が不可欠であるが、通性嫌
気性細菌として乳酸菌属細菌を含ませた場合には、この
乳酸菌の作用によって、嫌気性汚泥の生成が助長され強
固な凝集効果が一段と増大すると同時に、嫌気槽２にお
ける嫌気的条件の元での腐敗細菌の増殖に伴う腐敗状態
の進行が遅延され、従って腐敗臭の発生が防止される効
果がある。Due to this strong cohesive force and the effect of incorporating dissolved components as coagulation progresses, new sludge containing both aerobic and anaerobic bacteria is generated, and the purification effect of wastewater is promoted. . By the way, aerobic sludge and anaerobic sludge produced from the same wastewater have a strong cohesive force as described above, but on the other hand, aerobic sludge and anaerobic sludge produced from different wastewater It has been experimentally found that no cohesive force is generated between the two. This word indicates that the dye-resistance reaction is not simply due to Coulomb force or van der Waals force, but also the existence of a certain type of polymer bonding reaction. As anaerobic bacteria, it is essential to add the facultative anaerobic bacteria mentioned above, but when lactic acid bacteria are added as facultative anaerobic bacteria, the production of anaerobic sludge is inhibited by the action of these lactic acid bacteria. At the same time, the enhanced and strong coagulation effect is further increased, and at the same time, the progress of putrefaction due to the proliferation of putrefaction bacteria under anaerobic conditions in the anaerobic tank 2 is delayed, and therefore the occurrence of putrefaction odor is prevented.

このようにして、新たに生成した汚泥は強拍気槽３で強
曝気して好気性汚泥とした後、分離装置４へ送って廃水
と汚泥に分離し、分離して取り出した汚泥は汚泥脱水機
１０によって固液分離されて、固体部分はこの廃水処理
循環系外へ排出され、液体部分は好気槽５へ送られる。In this way, the newly generated sludge is strongly aerated in the strong air tank 3 to make it aerobic sludge, and then sent to the separator 4 where it is separated into wastewater and sludge, and the separated sludge is dehydrated. Solid-liquid separation is performed by the machine 10, and the solid portion is discharged outside the wastewater treatment circulation system, and the liquid portion is sent to the aerobic tank 5.

この分離装置４は第２図及び第３図に示する沈降槽形式
のものに限定されず、その他のｌａ械的、物理的手段に
よる分離装置をも含むものである。強拍気槽３における
強曝気は、分離装置４における廃水と汚泥の分離を容易
するためである。This separation device 4 is not limited to the sedimentation tank type shown in FIGS. 2 and 3, but also includes separation devices using other mechanical or physical means. The purpose of strong aeration in the strong air tank 3 is to facilitate separation of wastewater and sludge in the separation device 4.

尚、通性嫌気性細菌として乳酸菌属細菌が主体をなす場
合においては、分離装置４での引抜き汚泥は乳酸菌属細
菌等の嫌気性細菌の作用により、放置状態においても腐
敗が進行せず、従って、汚泥による二次公害はもたらさ
れない。In addition, when the facultative anaerobic bacteria are mainly bacteria of the genus Lactobacillus, the sludge extracted by the separation device 4 does not deteriorate even if left unattended due to the action of anaerobic bacteria such as bacteria of the genus Lactobacillus, and therefore , no secondary pollution is caused by sludge.

好気槽５においては、前記のように、分離装置４で汚泥
を分離した残余の廃水と汚泥脱水機１０で生じた液体部
分が、沈降分離槽６から汚泥ポンプ９により返送される
好気性汚泥と混合投入されて、送風機８から送り込まれ
る空気によって曝気される。分離装置４からの廃水の汚
濁濃度は薄くなっているので、沈降分離槽５からの好気
性汚泥と混合することにより、汚濁濃度を濃くして好気
槽５におけるズーグレア（Ｚｏｏｇｌｏｅａ）　ｆｓ細
菌を含む好気性細菌が活発化した新な好気性汚泥の生成
を可能ならしめるのである。これにより、分離装置４か
らの廃水が更に浄化される。In the aerobic tank 5, as described above, the residual wastewater after sludge separation in the separator 4 and the liquid portion generated in the sludge dehydrator 10 are mixed into aerobic sludge, which is returned from the sedimentation separation tank 6 by the sludge pump 9. The mixture is mixed with air and aerated with air sent from the blower 8. Since the pollution concentration of the wastewater from the separation device 4 is low, by mixing it with the aerobic sludge from the sedimentation separation tank 5, the pollution concentration is increased to contain Zoogloea fs bacteria in the aerobic tank 5. This enables the production of new aerobic sludge in which aerobic bacteria are activated. This further purifies the wastewater from the separator 4.

沈降分離槽６には、上述のようにして生成された好気性
ｌη泥を含む廃水が一定量連続的に人孔られる。そして
、この沈降分離槽６において沈降した好気性汚泥は汚泥
ポンプ９によって、前記のように、再唱気槽７及び好気
槽５の入口−・と分配して返送され、一方、上澄液の汚
濁濃度は好気槽５におりる新な好気性汚泥の生成によっ
て基準値以下に低下しているので、そのまま処理水とし
て放流される。A certain amount of wastewater containing the aerobic lη mud produced as described above is continuously fed into the sedimentation separation tank 6 . The aerobic sludge that has settled in the sedimentation separation tank 6 is distributed and returned to the inlets of the recasting tank 7 and the aerobic tank 5 by the sludge pump 9, as described above, while the supernatant liquid Since the pollution concentration of the water has been reduced to below the standard value due to the production of new aerobic sludge in the aerobic tank 5, it is discharged as is as treated water.

尚、嫌気槽２においては、運転開始前に投入された通性
嫌気性細菌を含む嫌気性細菌が曝気によって廃水の流出
入にもかかわらず増殖し続けて嫌気性汚泥を生成してい
るが、廃水の汚濁濃度が諸種の理由によって減少した場
合には前記嫌気性細菌の増殖が不可能となることも生し
得るので、第３図に示すように、沈降分離槽６で分離し
た好気性細菌が顕在化し嫌気性細菌が潜在化した好気性
Ｆ５泥を嫌気槽２へも返送する廃水処理循環系とするこ
とができる。この第２の発明の系の場合には、好気性汚
泥中に潜在化しいる嫌気性細菌が嫌気槽２で前記した陽
気によって顕在化し増殖することができるからである。In addition, in the anaerobic tank 2, anaerobic bacteria including facultative anaerobic bacteria that were added before the start of operation continue to proliferate due to aeration despite the inflow and outflow of wastewater, and produce anaerobic sludge. If the concentration of pollution in the wastewater decreases for various reasons, it may become impossible for the anaerobic bacteria to grow, so as shown in FIG. The wastewater treatment circulation system can also return to the anaerobic tank 2 the aerobic F5 mud in which anaerobic bacteria have become apparent and anaerobic bacteria have become latent. This is because, in the case of the system of the second invention, anaerobic bacteria latent in the aerobic sludge can be brought to the surface and multiplied by the above-mentioned positive air in the anaerobic tank 2.

このとき、好気性細菌は潜在化し、た状態となっている
。従って、この第２の発明の系εこおいては、嫌気槽２
を出た廃水中には、嫌気性細菌が顕在化し好気性細菌が
潜在化した嫌気性汚泥が含まれているが、この嫌気性汚
泥を含む廃水と沈降分離槽６から再曝気槽７を経由して
返送される好気性細菌が顕在化し嫌気性細菌が潜在化し
ている好気性汚泥が混合されて新たな汚泥を生成するの
は、前記系と同様である。又、この系の場合には、前記
沈降分離槽６で沈陣分離されて返送される汚泥の嫌気槽
２、好気槽５及び再曝気槽７への分配返送量は、嫌気槽
２への返送量が最も少く、再曝気槽又は好気槽５への返
送量の約１０分の１以下である。この理由は、嫌気槽２
への好気性汚泥の返送は、好気性汚泥中に好気性細菌と
共に顕潜在化している嫌気性細菌を廃水と混合して、嫌
気槽２内における嫌気的条件でこれら嫌気性細菌を増殖
するためであるので少くてよいが、再曝気槽７及び好気
槽５人口においては、廃水処理効果を高めるために多量
の返送が必要となるのである。しかし、廃水の汚濁濃度
が極端に低い場合には、嫌気槽２への返送量を前記量以
上に返送したり、あるいは、嫌気槽２の出口において、
図外の嫌気沈降槽を設けて得た嫌気濃縮汚泥を嫌気槽２
に直接戻すｌ・要がある。通性嫌気性細菌に乳酸菌属細
菌を含ませた場合の効果については、前記系と同じであ
る。At this time, aerobic bacteria are in a latent state. Therefore, in the system ε of this second invention, the anaerobic tank 2
The wastewater that exits contains anaerobic sludge in which anaerobic bacteria have become apparent and aerobic bacteria have become latent, and the wastewater containing this anaerobic sludge is passed from the sedimentation separation tank 6 to the reaeration tank 7. Similar to the system described above, the aerobic sludge that is returned and has exposed aerobic bacteria and latent anaerobic bacteria is mixed to generate new sludge. In addition, in the case of this system, the amount of sludge separated and returned to the anaerobic tank 2, aerobic tank 5, and reaeration tank 7 after being separated in the sedimentation separation tank 6 is equal to the amount of sludge returned to the anaerobic tank 2. The amount returned is the smallest, about one-tenth or less of the amount returned to the reaeration tank or aerobic tank 5. The reason for this is that the anaerobic tank 2
The purpose of returning the aerobic sludge to is to mix the anaerobic bacteria that have become visible and latent together with the aerobic bacteria in the aerobic sludge with wastewater, and to multiply these anaerobic bacteria under anaerobic conditions in the anaerobic tank 2. Therefore, a small amount is sufficient, but in the case of the reaeration tank 7 and the aerobic tank 5 population, a large amount of return is required to enhance the wastewater treatment effect. However, if the concentration of pollution in the wastewater is extremely low, the amount returned to the anaerobic tank 2 may be greater than the above amount, or at the outlet of the anaerobic tank 2,
Anaerobic thickened sludge obtained by installing an anaerobic settling tank (not shown) is transferred to anaerobic tank 2.
There is a need to return it directly to . The effects when the facultative anaerobic bacteria include bacteria belonging to the genus Lactic Acid Bacteria are the same as in the above system.

上記第１の発明と第２の発明の２つの廃水処理循環系の
説明において、嫌気槽２、強拍気槽３、好気槽５及び再
曝気槽７における曝気を送風機８から送り込まれる空気
によって行う例について説明したが、これに代えて、他
の手段による曝気であってもよいのは勿論である。In the above description of the two wastewater treatment circulation systems of the first invention and the second invention, aeration in the anaerobic tank 2, strong aerobic tank 3, aerobic tank 5, and reaeration tank 7 is carried out by air sent from the blower 8. Although an example in which aeration is carried out has been described, it goes without saying that aeration may be carried out by other means instead of this.

以上の説明から明らかなように、この発明方法は、同一
廃水処理循環系内において、好気性細菌が顕在化し嫌気
性細菌が潜在化した好気性汚泥と嫌気性細菌が顕在化し
た嫌気性汚泥を生成し、次に、これら２つの相反する物
理化学的性質を有する汚泥を混合することによって生じ
る親和性の増大及び粘着力などの相乗効果により生じる
強固な凝集力と６集の進行に伴う溶解成分の取り込み効
果によって、好気性細菌と嫌気性細菌が共に顕在化した
新たな汚泥を生成すると共に好気性汚泥の作用により廃
水の浄化をおこなうものである。そして、これらの新た
な汚泥の生成により廃水のＢＯＤａ度は激減されるため
に、廃水のＢＯＤ濃度が高い場合であっても、従来の活
性汚泥法のように廃水を稀釈してＢＯＤ濃度を低下させ
る必要はなくなるので、廃水量は増加せず、従って好気
槽等は小型のものでよ（なり廃水処理施設全体も小型化
されると共に運転管理が単純化される効果力くある。更
に、稀釈水の不要に伴う給水施設の諸経費の軽減化、好
気槽の小型化並びに汚濁負担の減少に伴って曝気量も少
くてよいために送風機の動力費が軽減されるなど運転経
費の大巾な軽減化を図ることができる。更に又、通性嫌
気性細菌として乳酸菌属細菌が含まれた場合には分離装
置で分ｚ１１シた汚泥にも乳酸菌属が含まれるため悪臭
の発生等の二次公害の発生が阻止される。又、強拍気槽
を設げることによって分離装置における廃水とｌη泥の
分離が容易となると共に、再曝気槽を設番すて、嫌気槽
からの嫌気性汚泥と沈降分離槽からの好気性汚泥を再曝
気して全体として好気性汚泥を生成するようにしたので
、沈降分離槽からの返送汚泥の濃度が低い場合であって
も、廃水処理することが可能となる。As is clear from the above explanation, the method of the present invention can separate aerobic sludge in which aerobic bacteria are exposed and anaerobic bacteria latent, and anaerobic sludge in which anaerobic bacteria are exposed, in the same wastewater treatment circulation system. Then, by mixing these two sludges with contradictory physicochemical properties, strong cohesive force occurs due to synergistic effects such as increased affinity and adhesive strength, and dissolved components as the sludge progresses. Due to the uptake effect, new sludge is generated in which both aerobic and anaerobic bacteria are present, and wastewater is purified by the action of aerobic sludge. The BODa content of the wastewater is drastically reduced by the generation of these new sludges, so even if the BOD concentration of the wastewater is high, the BOD concentration cannot be reduced by diluting the wastewater as in the conventional activated sludge method. Since there is no need to do this, the amount of wastewater does not increase, and therefore aerobic tanks, etc. can be made smaller (this has the effect of downsizing the entire wastewater treatment facility and simplifying operation and management.Furthermore, Reduced overheads for water supply facilities due to no need for diluted water, smaller aerobic tanks, and reduced pollution burden, which reduces the amount of aeration required, reducing blower power costs and other operating costs. Furthermore, if Lactobacillus bacteria are included as facultative anaerobic bacteria, the sludge separated by the separator will also contain Lactobacillus bacteria, which may cause problems such as the generation of bad odors. The occurrence of secondary pollution is prevented.In addition, by installing a strong aeration tank, it becomes easier to separate wastewater and lη mud in the separator, and a re-aeration tank can be installed to remove water from the anaerobic tank. Anaerobic sludge and aerobic sludge from the sedimentation tank are re-aerated to produce aerobic sludge as a whole, so even if the concentration of sludge returned from the sedimentation tank is low, wastewater treatment is possible. becomes possible.

次にこの発明の実施例を第２の発明の廃水処理循環系に
適用した場合について説明する。Next, a case will be described in which an embodiment of the present invention is applied to the wastewater treatment circulation system of the second invention.

廃水−水産加工廃水、ＢＯＤ濃度は６０００ｐｐｍ、−
日当りの廃水量５００ｔ。Wastewater - Fishery processing wastewater, BOD concentration is 6000 ppm, -
Amount of wastewater per day is 500 tons.

調整槽−廃水水質の調整傑作はなし、毎分的０．３４７
ｔの廃水を連続的に嫌気槽へ供給。Regulation tank - wastewater quality regulation No masterpiece, 0.347 per minute
t of wastewater is continuously supplied to the anaerobic tank.

嫌気槽−用分間当りの曝気量は１．５　ｍ／分（曝気槽
の１／１０の量） 廃水平均滞留時間は６時間。Anaerobic tank - Aeration volume per minute is 1.5 m/min (1/10 volume of the aeration tank) Average residence time of wastewater is 6 hours.

好気性汚泥の返送量は２５ｔ／日。The amount of aerobic sludge returned is 25 tons/day.

尚、嫌気槽における廃水の滞留時間は３時間辺上２４時
間以内が標準で、ＢＯＤ濃度により差異が生じる。Note that the standard residence time of wastewater in the anaerobic tank is between 3 hours and 24 hours, and it varies depending on the BOD concentration.

強拍気槽−廃水の滞留時間は１時間、２００　ｍ　／　
ＢＯＤｋｇ、　３．２５ｎ？／分。Strong air tank - residence time of wastewater is 1 hour, 200 m /
BODkg, 3.25n? /min.

分離装置−人口におけるＢ　ＯＤ　濃度は６０００ｐｐ
ｍ、出口におけるＢ　ＯＤ　’ｊＡ度は７５０ｐｐｍ　
（８２％減）。Separation device - B OD concentration in the population is 6000 pp
m, B OD 'jA degree at the exit is 750 ppm
(82% decrease).

廃水（汚泥）の平均滞留時間は約３０分。The average residence time of wastewater (sludge) is approximately 30 minutes.

生成された汚泥の量は３２ｔ／日。（９２％水分を含む
） 乾燥固体部分−２，６ｔ／Ｂ。The amount of sludge produced was 32 tons/day. (Contains 92% water) Dry solids portion - 2,6 t/B.

好気槽−人口におけるＢＯＤ濃度は５６０ｐｐｍ、出口
におけるＢＯＤ濃度は１１００ｐｐ。Aerobic tank - BOD concentration in the population is 560 ppm, BOD concentration at the outlet is 1100 ppm.

廃水（ｌη泥）の平均滞留時間は１６時間。The average residence time of wastewater (lη mud) is 16 hours.

好気性汚泥の返送量は２５０ｔ／日。The amount of aerobic sludge returned is 250 tons/day.

尚、好気槽乙こおける廃水（汚泥）の滞留時間は１２時
間以上２４時間以内が標準で、好気槽入口Ｂ　ＯＤ　Ｗ
ｉ度により差異が生じる。The standard retention time of wastewater (sludge) in the aerobic tank is 12 hours or more and less than 24 hours.
Differences occur depending on the i degree.

空気量を５０ｍ／ＢＯＤｋｇとして、 （７５０ｔ／日＋２５０ｔ／日）Ｘｏ、５６　（ＢＯＤ
濃度５６０ｐｐｍ）　ｘ　５０　ｍ　／　Ｂ　ＯＤ　ｋ
ｇ÷２４時間÷６０分Ｘ　２　／　３−１３．１ｍ／分
、 再曝気槽−汚泥の滞留時間４時間。５０ｎ（／ＢＯＤｋ
ｇ、　３．２５醒／分。Assuming the air volume is 50m/BODkg, (750t/day + 250t/day)Xo, 56 (BOD
Concentration 560ppm) x 50 m/B OD k
g ÷ 24 hours ÷ 60 minutes x 2 / 3 - 13.1 m/min, Re-aeration tank - sludge retention time 4 hours. 50n(/BODk
g, 3.25 wakes/min.

４ｇ　ｐｌ気１−１３．Ｉｎ？／分＋１．５　ｍ／分＋
３．２５ｍ／分＋３．２５耐／分−２１，１耐／分沈降
分離槽−人口におけるＢＯＤ濃度は１１００ｐｐ。4g pl 1-13. In? /min+1.5 m/min+
3.25 m/min + 3.25 resistance/min - 21,1 resistance/min settling tank - BOD concentration in population is 1100 pp.

放流する処理水のＢＯＤ濃度は規制値以内。BOD concentration in treated water discharged is within regulatory limits.

廃水（汚泥）の平均滞留時間は２時間。The average residence time of wastewater (sludge) is 2 hours.

放流する処理水の量は４９３ｔ／日。The amount of treated water discharged is 493 tons/day.

尚、同一条件の廃水を活性汚泥法で処理した場合と前実
施例との比較を述べる。A comparison will be made between the case where wastewater under the same conditions was treated by the activated sludge method and the previous example.

廃水のＢ　ＯＤ　濃度が６０００ｐｐｍであれば、通常
稀釈水によって２０００ｐｐｍ以下に稀釈しなければ活
性汚泥法においては処理が不能であるが、仮りに処理さ
れるものとして比較する。If the B OD concentration of the wastewater is 6000 ppm, it cannot be treated by the activated sludge method unless it is diluted to 2000 ppm or less with dilution water, but the comparison will be made assuming that it is treated.

前実施例と同様にＢＯＤ濃度１　ｋｇ処理するのに要す
る空気量を５Ｏｒ＋？／　Ｂ　ＯＤｋｇとして、５００
ｔ／日Ｘ６　　（ＢＯＤｃ度６０００ｐｐｍ　）　　Ｘ
５Ｑｒ＋？÷２４時間÷６０分−１０４ｒ＋？／分。As in the previous example, the amount of air required to process 1 kg of BOD concentration was set to 5Or+? / B ODkg, 500
t/day x6 (BODc degree 6000ppm)
5Qr+? ÷24 hours ÷ 60 minutes - 104r+? /min.

以上の２つの計算例でも明らかなように、この発明法に
よると、従来の活性汚泥法と消費電力の点で比較して、
送風機動力が約５分の１で済むので、大巾な電力を節約
することができる。As is clear from the above two calculation examples, according to this invention method, compared to the conventional activated sludge method in terms of power consumption,
Since the blower power is reduced to about one-fifth, a large amount of electricity can be saved.

尚、通常はこの廃水条件では処理できないので、３倍程
度に稀釈しなければならない。この場合、廃水量が３倍
程度になるために、諸設備の大型化、稀釈水の必要性、
運転操作の複雑化などの種々の欠点が生じる。Note that normally treatment cannot be performed under these wastewater conditions, so the wastewater must be diluted approximately three times. In this case, the amount of wastewater will triple, which will require larger equipment, the need for diluted water, etc.
Various drawbacks arise, such as complication of driving operations.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は従来の活性汚泥法の一般的なフローシート、第
２図及び第３図はこの発明方法のフローシート例をそれ
ぞれ示す。 ■−・調整槽、２・−嫌気槽、３−強拍気槽、４・−・
分！４を装置、５−好気槽、６−沈降分離槽、７−再眠
気槽。 特許出願人　　　　内　水　　　護 同代理人　　　　　渡　辺　三　彦 手続補正書（自発） ツノ−ゝ。 ′こ、 昭和５８年５゛月′イ３日 特許庁長官　若杉和夫殿 １、事件の表示 昭和５７年特許願第２０９０９２号。 ２、発明の名称 有機性物質を含む廃水の生物学的処理方法３、補正をす
る者 事件との関係　特許出願人 氏名　内水　　護 ４、代理人　〒５３０電話大＋ｈｏ６（３６１）　３８
３１住所　大阪市北区大融町２番２１号 （１）　　明細ｖＩ７の発明の詳細な説明の憫６、補正
の内容 （１）発明の詳♀ＩＩＩな説明の樹 ■　明細書第７頁第１６行目 「せる共に」を「せると共に」に補正する。 ■　明細書筒９．！″を第１９行目 「嫌気槽２供給」を「嫌気槽２から供給」に補正する。 ■　明細１店、第１１奥第１行目 「ににける」を「りこおりる」にン市正する。 ■　明細書第１２呉第２行目 「元での」を「下での号に補正する。 ■　明わ１１書第１２臭第２０行目 「泥によるｊを「記の腐敗臭による」に補正する。 ■　明イ：Ｈ書第１５貞第６行目 １−再曝気槽又は」を「再曝気槽７又は」に補正する。 以上FIG. 1 shows a general flow sheet for the conventional activated sludge method, and FIGS. 2 and 3 show examples of flow sheets for the method of the present invention. ■--adjustment tank, 2--anaerobic tank, 3-strong aerobic tank, 4--
Minute! 4 is an apparatus, 5-aerobic tank, 6-sedimentation separation tank, 7-re-drowsiness tank. Patent Applicant Uchimizu Mizuhiko Watanabe, Attorney-at-Law, Procedural Amendment (Voluntary) Tsuno-ゝ. Kazuo Wakasugi, Commissioner of the Japan Patent Office, dated May 3, 1982, 1. Indication of the case, Patent Application No. 209092 of 1988. 2. Name of the invention: Biological treatment method for wastewater containing organic substances 3. Relationship with the person making the amendment Patent applicant's name: Mamoru Naimizu 4, Agent: 530 Telephone University + HO6 (361) 38
31 Address 2-21 Oyu-cho, Kita-ku, Osaka (1) Detailed explanation of the invention in specification vI7 6, contents of amendments (1) Detailed explanation of the invention ■ Page 7 of the specification In the 16th line, ``Seruko'' is corrected to ``Serutoto''. ■ Statement tube9. ! '' on the 19th line, "Anaerobic tank 2 supply" is corrected to "Supply from anaerobic tank 2". ■ On the 1st store in the statement, change ``Ninikeru'' to ``Rikooriru'' in the 1st line of the 11th back. ■ In the 2nd line of the 12th Wu of the specification, ``formerly'' is amended to ``the number below.'' ■ In the 20th line of the 12th odor of the 11th book of Meiwa, ``j due to mud'' is changed to ``due to the rotten odor of the record.'' to correct. ■ Clear text: Book H, No. 15, line 6, 1-Reaeration tank or'' is corrected to ``Reaeration tank 7 or''. that's all

Claims (1)

【特許請求の範囲】 １、　有機性物質を含む廃水を調整槽から嫌気槽、再曝
気槽、強拍気槽、分離装置、好気槽及び沈降分離槽へと
送ると共に沈降分離槽で沈降分離した好気性汚泥を好気
槽及び再曝気槽を経由して前記強拍気槽の入口へ分配返
送させる廃水処理循環系であって、前記嫌気槽において
は、調整槽から供給される廃水を通性嫌気性細菌を含む
嫌気性細菌が顕在化した嫌気性汚泥の状態を維持するの
に適する曝気量で曝気し、前記再曝気槽においては、上
記嫌気槽から供給される嫌気性汚泥を含む廃水と沈降分
離槽から返送される好気性？ｒ５泥を混合し曝気してズ
ーグレア（Ｚｏｏｇｌｏｅａ）属細菌を含む好気性細菌
が活発化した好気性汚泥状態とした後、嫌気槽からの嫌
気性汚泥と該再曝気槽がらの好気性汚泥を混合して凝集
させた汚泥を含む廃水を強拍気槽で強曝気して全体とし
て好気性細菌が活発化した好気性汚泥の状態としてから
、分離装置で廃水と汚泥を分離して、汚泥は廃水処理循
環系外へ排出し、前記好気槽においては、上記分離装置
で汚泥を除いた廃水と沈降分離槽から返送される前記好
気性汚泥を含む廃水を混合したものを、陽気してズーグ
レア（Ｚｏｏｇｌｏｅａ）属細菌を含む好気性細菌が活
発化した好気性汚泥を生成させてから沈降分離槽へ送っ
て、上澄液と好気性汚泥を分δ）ｔし、上澄液は処理水
としてこの廃水処理循環系外へ排出し、好気性汚泥は前
記の通り、この廃水処理循環系内へ分配返送することを
特徴とする有機性物質を含む廃水の生物学的処理方法。 ２、前記通性嫌気性細菌が乳酸菌属細菌を含む通性嫌気
性細菌である特許請求の範囲第１項記載の有機性物質を
含む廃水の生物学的処理方法。 ３、　有機性物質を含む廃水を調整槽から嫌気槽、再曝
気槽、強拍気槽、分離装置、好気槽及び沈降分離槽へと
送ると共に沈降分ｚ）１糟で沈降分離した好気性汚泥を
好気槽及び再曝気槽を経由して前記強拍気槽の入口並び
に嫌気槽へ分配返送させる廃水処理循環系であって、前
記嫌気槽においては、調整槽から給水される廃水と沈降
分離槽から返送される好気性汚泥を混合したものを通性
嫌気性細菌を含む嫌気性細菌が顕在化した嫌気性汚泥の
状態を維持するのに適する曝気量で曝気し、前記再曝気
槽においては、上記嫌気槽から供給される嫌気性ｌη泥
を含む廃水と沈降分離槽から返送される好気性汚泥を混
合し曝気してズーグレア（Ｚｏｏｇｌ。 ｅａ）尿細菌を含む好気性細菌が活発化した好気性汚泥
の状態とした後、嫌気槽からの嫌気性汚泥と咳再曝気槽
からの好気性汚泥を混合して凝集させた汚泥を含む廃水
を強拍気槽で強曝気して全体として好気性細菌が活発化
した好気性汚泥の状態としてから、分離装置で廃水と汚
泥を分離して、汚泥は廃水処理循環系外へ排出し、前記
好気槽においては、上記分離装置で汚泥を除いた廃水と
沈降分！１ｉｌＩ槽から返送される好気性汚泥を混合し
たものを曝気と７でズーグレア（Ｚｏｏｇｌｏｅａ）尿
細菌を含む好気性細菌が活発化した好気性汚泥を生成さ
せてから沈降分離槽へ送って、上澄液と好気性汚泥を分
離し、上澄液は処理水としてこの廃水処理循環系外へ排
出し、好気性汚泥は前記の通り、この廃水処理循環系内
へ分配返送することを特徴とする有機性物質を含む廃水
の生物学的処理方法。 ４、　前記通性嫌気性細菌が乳酸菌Ｂ細菌を含む通性嫌
気性細菌である特許請求の範囲第３項記載の有機性物質
を含む廃水の生物学的処理方法。[Claims] 1. Sending wastewater containing organic substances from the adjustment tank to the anaerobic tank, reaeration tank, strong aeration tank, separation device, aerobic tank, and sedimentation tank, and performing sedimentation separation in the sedimentation tank. A wastewater treatment circulation system that distributes and returns the aerobic sludge to the inlet of the strong aerobic tank via an aerobic tank and a reaeration tank, and in the anaerobic tank, the wastewater supplied from the adjustment tank is passed through. The wastewater containing the anaerobic sludge supplied from the anaerobic tank is aerated at an aeration amount suitable for maintaining the state of anaerobic sludge in which anaerobic bacteria including anaerobic bacteria have become apparent. and aerobic water returned from the sedimentation tank? After mixing and aerating the R5 mud to create an aerobic sludge state in which aerobic bacteria including Zoogloea bacteria are activated, the anaerobic sludge from the anaerobic tank and the aerobic sludge from the reaeration tank are mixed. The wastewater containing the flocculated sludge is strongly aerated in a strong air tank to create an aerobic sludge state in which aerobic bacteria are activated as a whole, and then the wastewater and sludge are separated in a separator, and the sludge is separated from the wastewater. It is discharged outside the treatment circulation system, and in the aerobic tank, a mixture of the wastewater from which the sludge has been removed in the separation device and the wastewater containing the aerobic sludge returned from the sedimentation separation tank is mixed with zooglare ( After generating aerobic sludge in which aerobic bacteria including bacteria of the genus Zoogloea are activated, it is sent to a sedimentation separation tank to separate the supernatant liquid and aerobic sludge, and the supernatant liquid is used as treated water. A biological treatment method for wastewater containing organic substances, characterized in that the wastewater is discharged outside the wastewater treatment circulation system, and the aerobic sludge is distributed and returned to the wastewater treatment circulation system as described above. 2. The method for biological treatment of wastewater containing organic substances according to claim 1, wherein the facultative anaerobic bacteria are facultative anaerobic bacteria including bacteria of the genus Lactobacillus. 3. Send the wastewater containing organic substances from the adjustment tank to the anaerobic tank, reaeration tank, strong aerobic tank, separator, aerobic tank, and sedimentation separation tank, and collect the sedimentation fraction (z) aerobic water separated by sedimentation in 1 pot. A wastewater treatment circulation system that distributes and returns sludge to the inlet of the strong aerobic tank and the anaerobic tank via an aerobic tank and a reaeration tank, and in the anaerobic tank, wastewater supplied from the adjustment tank and sediment are separated. The mixed aerobic sludge returned from the separation tank is aerated with an amount of aeration suitable for maintaining the state of anaerobic sludge in which anaerobic bacteria including facultative anaerobic bacteria are exposed, and the mixture is aerated in the re-aeration tank. The wastewater containing the anaerobic lη mud supplied from the anaerobic tank was mixed with the aerobic sludge returned from the sedimentation separation tank and aerated to activate aerobic bacteria including zooglea (Zooglea) urine bacteria. After making it into an aerobic sludge state, the anaerobic sludge from the anaerobic tank and the aerobic sludge from the cough re-aeration tank are mixed and flocculated, and the wastewater containing the flocculated sludge is strongly aerated in the strong aerobic tank to improve the overall quality. After the aerobic sludge is in a state where airborne bacteria are activated, wastewater and sludge are separated in a separator, and the sludge is discharged outside the wastewater treatment circulation system, and in the aerobic tank, the sludge is removed by the separator. wastewater and sedimentation! The mixed aerobic sludge returned from the 1ilI tank is aerated and processed in Step 7 to produce aerobic sludge in which aerobic bacteria including Zoogloea bacteria are activated, and then sent to the sedimentation separation tank to remove the supernatant. The organic sludge is characterized in that the liquid and aerobic sludge are separated, the supernatant liquid is discharged as treated water outside the wastewater treatment circulation system, and the aerobic sludge is distributed and returned to the wastewater treatment circulation system as described above. Biological treatment method for wastewater containing pollutants. 4. The method for biological treatment of wastewater containing organic substances according to claim 3, wherein the facultative anaerobic bacteria are facultative anaerobic bacteria including lactic acid bacteria B.