JP4490659B2

JP4490659B2 - Sewage treatment system

Info

Publication number: JP4490659B2
Application number: JP2003285364A
Authority: JP
Inventors: 正彦堤; 原卓巳小
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 2003-08-01
Filing date: 2003-08-01
Publication date: 2010-06-30
Anticipated expiration: 2023-08-01
Also published as: JP2005052721A

Description

本発明は、下水処理場、産業排水処理設備等において、微生物を利用して下水（産業排水を含む）中の有機物や固形物や栄養塩類などの汚濁物質を分解除去する下水処理システムに関するものである。 The present invention relates to a sewage treatment system that decomposes and removes organic matter, solid matter, nutrient salts, and other pollutants in sewage (including industrial wastewater) using microorganisms in sewage treatment plants, industrial wastewater treatment facilities, and the like. is there.

一般に、下水処理場においては、活性汚泥中に含まれる微生物が有する汚濁物質分解作用を利用する処理が行われている。このような活性汚泥微生物により、比較的分解の容易な易分解性物質を資化して除去することができる。しかし、処理対象となる下水中には、このような活性汚泥微生物では充分に分解しきれない、例えばフミン酸、フルボ酸、油分等の難分解性物質が多く含まれていることがある。そこで、最近は、活性汚泥微生物のような易分解性物質処理微生物の他に、難分解性物質処理微生物を併用することも行われている。 In general, in a sewage treatment plant, treatment using a pollutant decomposing action of microorganisms contained in activated sludge is performed. Such activated sludge microorganisms can assimilate and remove easily degradable substances that are relatively easy to decompose. However, the sewage to be treated may contain a large amount of hardly decomposable substances such as humic acid, fulvic acid, and oil that cannot be sufficiently decomposed by such activated sludge microorganisms. Therefore, recently, in addition to easily decomposable substance-treated microorganisms such as activated sludge microorganisms, it is also used in combination with hardly degradable substance treated microorganisms.

ここで、難分解性物質を処理する技術としては、例えば特許文献１〜３に開示されているものがある。特許文献１には、担子菌に対して糖類を基質として好気条件下で培養することにより難分解性物質であるフミン酸を処理する微生物の増殖技術が開示されている。特許文献２には、バチルスなどの微生物群とフミン酸及び分解酵素とを汚水へ供給して浄化処理する技術が開示されている。特許文献３には、バチルスなどの微生物群と、フミン酸を含む基質とを混合した微生物剤が開示されている。 Here, as a technique for processing a hardly decomposable substance, for example, there are those disclosed in Patent Documents 1 to 3. Patent Document 1 discloses a technique for growing a microorganism that treats humic acid, which is a hardly degradable substance, by culturing basidiomycetes on a saccharide as a substrate under aerobic conditions. Patent Document 2 discloses a technology for purifying by supplying a microbial group such as Bacillus, humic acid, and a degrading enzyme to sewage. Patent Document 3 discloses a microbial agent in which a microbial group such as Bacillus and a substrate containing humic acid are mixed.

これらの特許文献１〜３により図１１のような従来システムが考えられる。下水が最初沈殿池１に導入されると、最初沈殿池１内では大きな固形物が沈殿分離され、上澄み液が反応槽２内に送出されるようになっている。この反応槽２内には有用微生物である易分解性物質処理微生物（活性汚泥微生物）３及び難分解性物質処理微生物４が存在している。したがって、反応槽２内において、活性汚泥等の易分解性物質は易分解性物質処理微生物３の分解・資化機能により低減され、フミン酸等の難分解性物質は難分解性物質処理微生物４の分解・資化機能により低減されるようになっている。そして、易分解性物質及び難分解性物質が低減された処理水は下流側の最終沈殿池５に送られて資化増殖した微生物が沈殿分離された後、塩素混和池６に送られるようになっている。塩素混和池６に送られた処理水は消毒剤である塩素と混和され、この処理水中に含まれる大腸菌群等の有害微生物の殺菌が行われた後、河川へ放流水として放流されるようになっている。 A conventional system as shown in FIG. When sewage is first introduced into the settling basin 1, a large solid is precipitated and separated in the first settling basin 1, and the supernatant liquid is sent into the reaction tank 2. In the reaction tank 2, there are easily degradable substance-treated microorganisms (activated sludge microorganisms) 3 and hardly degradable substance-treated microorganisms 4 which are useful microorganisms. Therefore, in the reaction tank 2, easily degradable substances such as activated sludge are reduced by the decomposition and assimilation function of the easily decomposable substance-treated microorganism 3, and persistent substances such as humic acid are reduced. It has been reduced by the decomposition and assimilation function. The treated water in which the easily decomposable substance and the hardly decomposable substance are reduced is sent to the final settling basin 5 on the downstream side, and the microorganisms that have been assimilated and proliferated are separated and then sent to the chlorine mixing pond 6. It has become. The treated water sent to the chlorine-mixing pond 6 is mixed with the disinfectant chlorine, and after sterilizing harmful microorganisms such as coliform bacteria contained in the treated water, it is discharged into the river as discharge water. It has become.

最終沈殿池５の底部には水配管７が設けられており、沈殿した微生物は返送汚泥として返送汚泥ポンプ８により反応槽２の前段側に返送され、また残りは余剰汚泥として余剰汚泥ポンプ９により汚泥処理プロセスへ供給されるようになっている。 A water pipe 7 is provided at the bottom of the final sedimentation basin 5, and the settled microorganisms are returned to the upstream side of the reaction tank 2 by a return sludge pump 8 as return sludge, and the remainder is supplied by excess sludge pump 9 as excess sludge. It is supplied to the sludge treatment process.

反応槽２の底部には散気管１０が配設されている。この散気管１０には、バルブ１１を介してブロア１２からエアが送りこまれるようになっており、このエアが気泡１３となって反応槽２内の水に供給されるようになっている。そして、この気泡１３により水中に溶解した溶存酸素が易分解性物質処理微生物３と接触混合し、この混合の過程で易分解性物質の資化が行われる。 An aeration tube 10 is disposed at the bottom of the reaction tank 2. The air diffuser 10 is supplied with air from a blower 12 through a valve 11, and the air is supplied as bubbles 13 to the water in the reaction tank 2. Then, dissolved oxygen dissolved in water by the bubbles 13 contacts and mixes with the easily decomposable substance-treated microorganism 3, and utilization of the easily decomposable substance is performed during the mixing process.

培養槽１４には培養液１５が貯溜されており、この培養液１５中に難分解性物質処理微生物４が培養されている。培養槽１４の底部には散気管１６が配設されており、この散気管１６にはコンプレッサ１７からエアが送りこまれ、このエアが気泡１８となって培養液１５中に供給されるようになっている。また、培養液１５には、難分解性物質処理微生物４の栄養源となる基質１９が投入されるようになっている。この基質１９と、気泡１８により供給される酸素とにより培養液１５中に存在する難分解性物質処理微生物４が高速で増殖されることになる。 A culture solution 15 is stored in the culture tank 14, and the hardly decomposable substance-treated microorganism 4 is cultured in the culture solution 15. An air diffuser 16 is provided at the bottom of the culture tank 14, and air is sent from the compressor 17 to the air diffuser 16, and the air is supplied as bubbles 18 into the culture solution 15. ing. In addition, a substrate 19 serving as a nutrient source for the hardly decomposable substance-treated microorganism 4 is introduced into the culture solution 15. The substrate 19 and the oxygen supplied by the bubbles 18 cause the hardly decomposable substance-treated microorganism 4 present in the culture solution 15 to grow at a high speed.

一般に、難分解性物質処理微生物４は易分解性物質処理微生物３ほどには強い繁殖力を持たず、また、易分解性物質処理微生物３により補食されたり淘汰されたりするという性質を持っている。したがって、反応槽２の運転がある程度の期間行われると、反応槽２内の難分解性物質処理微生物４の数は次第に減少し、そのため反応槽２での難分解性物質の処理機能が次第に低下してくる。培養槽１４は、このような難分解性物質処理微生物４の性質を考慮して設けられたものであり、供給ポンプ２０により培養槽１４内の難分解性物質処理微生物４が反応槽２内へ供給され補充されることにより、難分解性物質処理微生物４の減少を抑制し、難分解性物質に対する処理機能の低下の防止が図られるようになっている。
特開平２−１８０００号公報特開平５−３０５２９６号公報特開平１０−２７７５８６号公報 In general, the hardly decomposable substance-treated microorganism 4 does not have as strong a fertility as the easily degradable substance treated microorganism 3, and has the property of being supplemented or deceived by the easily degradable substance treated microorganism 3. Yes. Therefore, when the operation of the reaction tank 2 is performed for a certain period, the number of the hardly decomposable substance-treated microorganisms 4 in the reaction tank 2 gradually decreases, so that the function of treating the hardly decomposable substance in the reaction tank 2 gradually decreases. Come on. The culture tank 14 is provided in consideration of such properties of the hardly decomposable substance-treated microorganism 4, and the hardly degradable substance treated microorganism 4 in the culture tank 14 is brought into the reaction tank 2 by the supply pump 20. By being supplied and replenished, the decrease of the hardly decomposable substance-treated microorganism 4 is suppressed, and the reduction of the treatment function for the hardly decomposable substance is prevented.
Japanese Patent Laid-Open No. 2-18000 JP-A-5-305296 Japanese Patent Laid-Open No. 10-277586

しかし、難分解性物質処理微生物４は、バチルス属などの自然界の土壌から採取されスクリーニングされた微生物であり、下水処理場の環境には馴染みにくい微生物である。つまり、難分解性物質処理微生物４を補食する易分解性物質処理微生物３が存在したり、送りこまれる下水中に難分解性物質処理微生物４の増殖を阻害する成分が含まれていたり、BOD-SS負荷やHRT（水理学的滞留時間）等の水処理運転条件が合わなかったりすることなどがあるために、通常、難分解性物質処理微生物４が反応槽２内の環境に適応するのは困難である。そのため、多くの難分解性物質処理微生物４が死滅して、その数が減少し、難分解性物質の処理機能を一定レベル以上に向上させることができなかった。 However, the hardly decomposable substance-treated microorganism 4 is a microorganism that has been collected and screened from natural soil such as Bacillus, and is difficult to adapt to the environment of the sewage treatment plant. In other words, there are easily degradable substance-treated microorganisms 3 that supplement the hardly degradable substance-treated microorganisms 4, or components that inhibit the growth of the hardly degradable substance-treated microorganisms 4 are contained in the sewage that is fed. -Since the water treatment operation conditions such as SS load and HRT (hydraulic residence time) may not be met, the microorganisms 4 that are difficult to decompose are usually adapted to the environment in the reaction tank 2 It is difficult. Therefore, many persistent microbe-treated microorganisms 4 are killed, the number thereof is reduced, and the function of treating the hardly decomposable substance cannot be improved to a certain level or more.

図１２はこのような情況を示す特性図であり、（ａ）は培養槽１４内における難分解性物質処理微生物４の濃度X1、（ｂ）は反応槽２内における難分解性物質処理微生物４の濃度X2、（ｃ）は河川に放流される放流水に含まれる難分解性物質の濃度S1をそれぞれ示している。 FIG. 12 is a characteristic diagram showing such a situation. (A) is the concentration X1 of the hardly decomposable substance-treated microorganism 4 in the culture tank 14, and (b) is the hardly decomposable substance treated microorganism 4 in the reaction tank 2. Concentrations X2 and (c) respectively indicate the concentration S1 of the hardly decomposable substance contained in the discharged water discharged into the river.

この図において、時刻ｔ1，ｔ2，ｔ3は供給ポンプ２０が運転されるタイミングを示している。（ａ）に示されるように、各時刻で供給ポンプ２０が起動された直後は、培養槽１４内の難分解性物質処理微生物４の濃度X1は一時的に低下するが、その後再増殖されるために濃度X1は再び元のレベルに復帰する。一方、反応槽２では、（ｂ）に示されるように、供給ポンプ２０の起動直後は培養槽１４からの供給により難分解性物質処理微生物４の濃度X2は一時的に増加するが、上述した易分解性物質処理微生物３による補食や下水中の増殖阻害成分、あるいは水処理運転の不適合などの影響により間もなく減少してしまう。結局、（ｃ）に示されるように、放流水中の難分解性物質の濃度S1は供給ポンプ２０の起動直後に一時的に低減されるものの直ぐに元のレベルに戻ってしまい、充分な難分解性物質処理能力を得ることができなかった。 In this figure, times t1, t2, and t3 indicate timings at which the supply pump 20 is operated. As shown in (a), immediately after the supply pump 20 is started at each time, the concentration X1 of the hardly decomposable substance-treated microorganism 4 in the culture tank 14 is temporarily reduced, but then re-proliferated. Therefore, the concentration X1 returns to the original level again. On the other hand, in the reaction tank 2, as shown in (b), the concentration X2 of the hardly decomposable substance-treated microorganism 4 temporarily increases due to the supply from the culture tank 14 immediately after the supply pump 20 is started. It will soon decrease due to the effects of supplementation by the readily degradable substance-treated microorganism 3, growth inhibition components in sewage, or incompatibility of water treatment operation. Eventually, as shown in (c), although the concentration S1 of the hardly decomposable substance in the effluent is temporarily reduced immediately after the supply pump 20 is started, it immediately returns to the original level, so that it is sufficiently difficult to decompose. Material processing capacity could not be obtained.

本発明は上記事情に鑑みてなされたものであり、難分解性物質処理微生物の減少を抑制し、難分解性物質に対する充分な処理機能を確保することが可能な下水処理システムを提供することを目的としている。 The present invention has been made in view of the above circumstances, and provides a sewage treatment system capable of suppressing the decrease in microorganisms treated with hardly decomposable substances and ensuring a sufficient treatment function for the hardly degradable substances. It is aimed.

上記課題を解決するための手段として、請求項１記載の発明は、易分解性物質処理微生物と共に難分解性物質処理微生物が存在しており、この難分解性物質処理微生物が有する分解・資化機能を利用して導入下水中に含まれる難分解性物質の除去を行う反応槽と、前記難分解性物質処理微生物が培養されており、前記反応槽内の難分解性物質処理微生物が低減した場合に、この難分解性物質処理微生物を前記反応槽に対して補充する培養槽と、を備えた下水処理システムにおいて、前記反応槽の下流側に位置する個所であって且つシステム外部の河川へ放流水を排出する排出口付近の個所から、馴化された難分解性物質処理微生物が存在している河川底泥を含む水を前記培養槽へ還流させる馴化微生物還流手段を備えた、ことを特徴とする。 As a means for solving the above-mentioned problems, the invention according to claim 1 is characterized in that the microorganisms treated with the hardly decomposable substance exist together with the microorganisms treated with the easily degradable substance , and the degradation / utilization of the microorganism treated with the hardly decomposed substance The reaction tank that removes the hardly decomposable substance contained in the introduced sewage using the function and the hardly decomposable substance treated microorganism are cultured, and the hardly degradable substance treated microorganism in the reaction tank is reduced. In this case, in a sewage treatment system comprising a culture tank for replenishing the reaction tank with the hardly decomposable substance-treated microorganism, the plant is located on the downstream side of the reaction tank and to a river outside the system. It is equipped with a conditioned microorganism return means for returning water containing river bottom mud containing conditioned refractory substance-treated microorganisms from the vicinity of the discharge port for discharging the discharged water to the culture tank. And

請求項２記載の発明は、請求項１記載の発明において、前記培養槽に対し、人工的に生成した基質の供給、又はシステム内部の所定個所から採取した難分解性物質の基質としての供給を、行う基質供給手段を備えた、ことを特徴とする。 The invention according to claim 2 is the invention according to claim 1, wherein supply of the artificially generated substrate or supply of a hardly degradable substance collected from a predetermined location inside the system as the substrate to the culture tank is performed. The substrate supply means for performing is provided.

請求項３記載の発明は、請求項１記載の発明において、前記反応槽の下流側に最終沈殿池が設置されると共に、該最終沈殿池の一部の領域に前記難分解性物質処理微生物が存在しており、前記培養槽で培養している前記難分解性物質処理微生物の補充を、前記反応槽に代えて該最終沈殿池に対して行うようにした、ことを特徴とする。 The invention according to claim 3 is the invention according to claim 1, wherein a final sedimentation basin is installed on the downstream side of the reaction tank, and the hardly decomposable substance-treated microorganism is present in a partial region of the final sedimentation basin. Replenishment of the hardly decomposable substance-treated microorganisms that exist and are cultured in the culture tank is performed on the final sedimentation basin instead of the reaction tank.

請求項４記載の発明は、請求項１乃至３のいずれかに記載の発明において、前記反応槽内及び前記培養槽内には、各下水中及び培養液中に外部空気を供給するための散気管が配設されており、これら両散気管に対する外部空気の供給は１台のブロアを共用して行う、ことを特徴とする。 According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, a dispersion for supplying external air into the sewage and the culture solution is provided in the reaction tank and the culture tank. A trachea is provided, and external air is supplied to both the air diffusers by using one blower in common.

請求項５記載の発明は、請求項１乃至４のいずれかに記載の発明において、前記反応槽に存在する難分解性物質処理微生物を第１の難分解性物質処理微生物、この第１の難分解性物質処理微生物を培養する前記培養槽を第１の培養槽、前記還流手段を第１の還流手段とした場合に、前記反応槽の上流側に最初沈殿池が設置されると共に、この最初沈殿池に存在する第２の難分解性物質処理微生物を培養する第２の培養槽が設置され、この最初沈殿池又はその付近の個所から馴化された第２の難分解性物質処理微生物を含む水を該第２の培養槽へ還流させる第２の還流手段が設けられており、前記第２の還流手段により前記第２の難分解性物質処理微生物が前記最初沈殿池に対して補充される、ことを特徴とする。 The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the hardly decomposable substance-treated microorganism present in the reaction tank is designated as the first hardly degradable substance treated microorganism, the first difficulty. When the culture tank for culturing the degradable substance-treated microorganism is the first culture tank and the reflux means is the first reflux means, a first sedimentation basin is installed upstream of the reaction tank, A second culture tank for culturing the second persistent substance-treating microorganism existing in the sedimentation basin is installed, and includes the second persistent substance-treating microorganism conditioned from the first sedimentation basin or the vicinity thereof Second reflux means for refluxing water to the second culture tank is provided, and the second persistent microorganisms are replenished to the first sedimentation basin by the second reflux means. It is characterized by that.

請求項６記載の発明は、請求項１乃至４のいずれかに記載の発明において、前記反応槽に存在する難分解性物質処理微生物を第１の難分解性物質処理微生物、この第１の難分解性物質処理微生物を培養する前記培養槽を第１の培養槽、前記還流手段を第１の還流手段とした場合に、前記反応槽の下流側に最終沈殿池が設置されると共に、この最終沈殿池に存在する第２の難分解性物質処理微生物を培養する第２の培養槽が設置され、この最終沈殿池又はその付近の個所から馴化された第２の難分解性物質処理微生物を含む水を該第２の培養槽へ還流させる第２の還流手段が設けられており、前記第２の還流手段により前記第２の難分解性物質処理微生物を前記最終沈殿池に対して補充する、ことを特徴とする。 The invention according to claim 6 is the invention according to any one of claims 1 to 4, wherein the hardly decomposable substance-treated microorganism present in the reaction tank is designated as the first hardly degradable substance treated microorganism, the first difficulty. When the culture tank for culturing the degradable substance-treated microorganism is the first culture tank and the reflux means is the first reflux means, a final sedimentation basin is installed on the downstream side of the reaction tank. A second culture tank for culturing the second persistent substance-treated microorganism existing in the sedimentation basin is installed, and includes the second persistent substance-treated microorganism acclimatized from the final sedimentation basin or the vicinity thereof. Second reflux means for refluxing water to the second culture tank is provided, and the second refractory substance-treated microorganism is replenished to the final sedimentation basin by the second reflux means. It is characterized by that.

以上のように、本発明に係る下水処理方法及び下水処理システムによれば、難分解性物質処理微生物の減少を抑制し、難分解性物質に対する充分な処理機能を確保することができる。 As described above, according to the sewage treatment method and the sewage treatment system according to the present invention, it is possible to suppress a decrease in the hardly decomposable substance-treated microorganisms and ensure a sufficient treatment function for the hardly decomposable substance.

図１は、本発明の第１の実施形態に係る下水処理システムの構成図である。図１が図１１と異なる点は、河川の下水処理場放流口付近の底泥２３を含む水を、馴化微生物還流手段としての供給ポンプ２４が培養槽１４に供給するようになっている点である。 FIG. 1 is a configuration diagram of a sewage treatment system according to the first embodiment of the present invention. 1 differs from FIG. 11 in that water including bottom mud 23 in the vicinity of the river sewage treatment plant outlet is supplied to the culture tank 14 by a supply pump 24 as a conditioned microorganism return means. is there.

放流口付近の底泥２３は、フミン酸等の難分解性物質を多く含んでいる放流水と接触しているので、その中には下水処理場の環境に馴化され、これらの難分解性物質を処理可能な難分解性物質処理微生物が存在している。したがって、この底泥２３を含んでいる水を供給ポンプ２４により培養槽１４内に供給してやれば、培養槽１４内には馴化された難分解性物質処理微生物４Ａが投入される。そして、図１の構成では、この下水処理場の環境に馴化された難分解性物質処理微生物４Ａを、培養槽１４内で培養し増殖して供給ポンプ２０により反応槽２内に供給するようになっている。 The bottom mud 23 in the vicinity of the discharge outlet is in contact with the discharge water containing a large amount of refractory substances such as humic acid, and therefore, it is acclimatized to the environment of the sewage treatment plant, and these refractory substances are included. There exist microorganisms that are capable of treating refractory substances. Therefore, if water containing the bottom mud 23 is supplied into the culture tank 14 by the supply pump 24, the acclimatized hardly decomposable substance-treated microorganism 4A is introduced into the culture tank 14. In the configuration of FIG. 1, the hardly decomposable substance-treated microorganism 4A acclimatized to the environment of the sewage treatment plant is cultured and grown in the culture tank 14 and supplied into the reaction tank 2 by the supply pump 20. It has become.

この難分解性物質処理微生物４Ａは、下水処理場の環境に馴化されているために、易分解性物質処理微生物３に補食されたり、下水中の水質成分により増殖が阻害されたりすることがなく、また、BOD-SS負荷やHRT（水理学的滞留時間）等の水処理運転条件にも合致する。したがって、反応槽２における難分解性物質に対する処理機能を向上させることができる。 Since this hardly decomposable substance-treated microorganism 4A is acclimatized to the environment of the sewage treatment plant, it may be supplemented by the easily degradable substance-treated microorganism 3 or its growth may be inhibited by water quality components in the sewage. It also meets the water treatment operating conditions such as BOD-SS load and HRT (hydraulic residence time). Therefore, the processing function for the hardly decomposable substance in the reaction tank 2 can be improved.

図２は、反応槽２における難分解性物質に対する処理機能の向上を示す特性図であり、（ａ）は培養槽１４内における難分解性物質処理微生物Ａ４の濃度X1、（ｂ）は反応槽２内における難分解性物質処理微生物４Ａの濃度X2、（ｃ）は河川に放流される放流水に含まれる難分解性物質の濃度S1をそれぞれ示している。 FIG. 2 is a characteristic diagram showing the improvement of the treatment function for the hardly decomposable substance in the reaction tank 2, wherein (a) is the concentration X1 of the hardly decomposable substance-treated microorganism A4 in the culture tank 14, and (b) is the reaction tank. 2, the concentration X2 and (c) of the hardly decomposable substance-treated microorganism 4A indicate the concentration S1 of the hardly decomposable substance contained in the discharged water discharged into the river.

この図において、時刻ｔ1，ｔ2，ｔ3は供給ポンプ２０が運転されるタイミングを示している。（ａ）に示されるように、各時刻で供給ポンプ２０が起動された直後は、培養槽１４内の難分解性物質処理微生物４Ａの濃度X1は一時的に低下するが、その後再増殖されるために濃度X1は再び元のレベルに復帰する。この特性は図１２の場合と同様である。一方、反応槽２では、（ｂ）に示されるように、時刻ｔ1で供給ポンプ２０が起動されると培養槽１４からの供給により難分解性物質処理微生物４Ａの濃度X2は、時刻ｔ1直後は急激に増加し、その後は時刻ｔ2まで減少することなく緩やかに増加し続ける。そして、時刻ｔ2で供給ポンプ２０が再度起動されると、濃度X2は、時刻ｔ2直後は急激に増加し、その後は時刻ｔ3まで減少することなく緩やかに増加し続ける。時刻ｔ3以降も同様の状態で濃度X2が増加する。 In this figure, times t1, t2, and t3 indicate timings at which the supply pump 20 is operated. As shown in (a), immediately after the supply pump 20 is started at each time, the concentration X1 of the hardly decomposable substance-treated microorganism 4A in the culture tank 14 is temporarily reduced, but is then regrown. Therefore, the concentration X1 returns to the original level again. This characteristic is the same as in the case of FIG. On the other hand, in the reaction tank 2, as shown in (b), when the supply pump 20 is started at time t1, the concentration X2 of the hardly decomposable substance-treated microorganism 4A by the supply from the culture tank 14 is immediately after time t1. It increases rapidly and then continues to increase slowly without decreasing until time t2. When the supply pump 20 is started again at time t2, the concentration X2 increases rapidly immediately after time t2, and then continues to increase gently without decreasing until time t3. The concentration X2 increases in the same state after time t3.

したがって、塩素混和池６から放流される放流水中の難分解性物質の濃度S1も、（ｂ）に示した濃度X2の増加に対応するように、元のレベルに戻ることなく低減され続け、充分な難分解性物質処理能力を示す結果となっている。なお、本実施形態では、供給ポンプ２０の運転を時刻ｔ1，ｔ2，ｔ3のタイミングで示すように間欠的な運転としているが、供給量を調整しながら連続的な運転とすることも可能である。 Therefore, the concentration S1 of the hardly decomposable substance in the effluent discharged from the chlorine mixing pond 6 continues to be reduced without returning to the original level so as to correspond to the increase in the concentration X2 shown in (b). The result shows the ability to treat difficult persistent substances. In the present embodiment, the operation of the supply pump 20 is intermittent as shown at the timings t1, t2, and t3. However, it is possible to perform continuous operation while adjusting the supply amount. .

図３は、本発明の第１の参考例に係る下水処理システムの構成図である。図３が図１と異なる点は、馴化微生物還流手段としての供給ポンプ２４が、塩素混和池６の出口付近の放流水を培養槽１４に供給するようになっている点である。このような塩素混和池６の出口付近の放流水中に含まれる難分解性物質処理微生物４Ａは消毒剤である塩素の存在にかかわらず生存してきたものである。したがって、このような微生物を培養槽１４に供給することにより、耐塩素性を有する難分解性物質処理微生物４Ａを獲得し、これを増殖して反応槽２へ供給することができる。 FIG. 3 is a configuration diagram of the sewage treatment system according to the first reference example of the present invention. 3 is different from FIG. 1 in that a supply pump 24 as a conditioned microorganism reflux means supplies the effluent water near the outlet of the chlorine mixing pond 6 to the culture tank 14. Such a hardly decomposable substance-treated microorganism 4A contained in the discharged water near the outlet of the chlorine-mixing pond 6 has survived regardless of the presence of chlorine as a disinfectant. Therefore, by supplying such microorganisms to the culture tank 14, it is possible to acquire the hardly decomposable substance-treated microorganism 4A having chlorine resistance, and to proliferate and supply it to the reaction tank 2.

図４は、本発明の第２の参考例に係る下水処理システムの構成図である。この図４では、図１及び図３において省略されていた汚泥処理系が図示されている。すなわち、余剰汚泥ポンプ９からの余剰汚泥は汚泥濃縮槽２５に送られ、ここで濃縮された後、濃縮汚泥ポンプ２６により汚泥消化槽２７に送られる。汚泥消化槽２７で消化された汚泥は、消化汚泥ポンプ２８により汚泥脱水機２９に送られて脱水され、この脱水作用により液状から固形状つまりケーキのような形状をした所謂「脱水ケーキ」が生成される。また、最初沈殿池１の底部からは生汚泥引抜ポンプ３０により生汚泥が引き抜かれ、この生汚泥が余剰汚泥ポンプ９からの余剰汚泥と共に汚泥濃縮槽２５に送られて処理されるようになっている。 FIG. 4 is a configuration diagram of a sewage treatment system according to a second reference example of the present invention. In FIG. 4, a sludge treatment system omitted in FIGS. 1 and 3 is shown. That is, the excess sludge from the excess sludge pump 9 is sent to the sludge concentration tank 25, concentrated here, and then sent to the sludge digestion tank 27 by the concentrated sludge pump 26. The sludge digested in the sludge digestion tank 27 is sent to a sludge dewatering machine 29 by a digested sludge pump 28 and dehydrated, and this dewatering action produces a so-called “dehydrated cake” that is shaped like a cake from a liquid. Is done. Moreover, raw sludge is extracted from the bottom of the sedimentation tank 1 by the raw sludge extraction pump 30, and this raw sludge is sent to the sludge concentration tank 25 together with the excess sludge from the excess sludge pump 9 for processing. Yes.

そして、供給ポンプ２４は汚泥濃縮槽２５の底部から濃縮汚泥を引き抜き、これを培養槽１４に供給するようになっている。この濃縮汚泥中には難分解性物質処理微生物４Ａが生息しているが、この濃縮汚泥中には、また活性汚泥微生物などの易分解性物質処理微生物３も生息している。したがって、この難分解性物質処理微生物４Ａは易分解性物質処理微生物３との共存可能性が大きく、易分解性物質処理微生物３が増殖した汚泥を減量化する機能を有している。なお、図４では、汚泥濃縮槽２５からの汚泥を培養槽１４に供給する例を示したが、汚泥消化槽２７からの汚泥や汚泥脱水機２９からの汚泥、あるいは最終沈殿池５からの汚泥を引き抜き、これを培養槽１４に供給する構成としてもよい。 The supply pump 24 draws the concentrated sludge from the bottom of the sludge concentration tank 25 and supplies it to the culture tank 14. In this concentrated sludge, the hardly decomposable substance-treated microorganism 4A lives, but in this concentrated sludge, the easily degradable substance treated microorganism 3 such as activated sludge microorganisms also lives. Therefore, the hardly decomposable substance-treated microorganism 4A has a high possibility of coexistence with the easily degradable substance treated microorganism 3, and has a function of reducing the amount of sludge on which the easily degradable substance treated microorganism 3 has grown. 4 shows an example in which the sludge from the sludge concentration tank 25 is supplied to the culture tank 14, the sludge from the sludge digestion tank 27, the sludge from the sludge dehydrator 29, or the sludge from the final sedimentation tank 5 is shown. It is good also as a structure which pulls out and supplies this to the culture tank 14. FIG.

図５は、本発明の第２の実施形態に係る下水処理システムの構成図である。図５が図１と異なる点は、最終沈殿池５から塩素混和池６に送出される処理水が基質供給ポンプ３１により培養槽１４に供給されるようになっている点である。すなわち、この処理水中には難分解性物質が含まれれており、この難分解性物質は培養槽１４内に生息している難分解性物質処理微生物４Ａの栄養源つまり基質となり得るものである。したたがって、この難分解性物質を基質供給ポンプ３１により培養槽１４内に供給することにより、難分解性物質処理微生物４Ａを高速に増殖することができるようになる。 FIG. 5 is a configuration diagram of a sewage treatment system according to the second embodiment of the present invention. FIG. 5 differs from FIG. 1 in that treated water sent from the final sedimentation basin 5 to the chlorine mixing basin 6 is supplied to the culture tank 14 by the substrate supply pump 31. That is, the treated water contains a hardly decomposable substance, and this hardly degradable substance can serve as a nutrient source, that is, a substrate for the hardly decomposable substance treated microorganism 4A inhabiting in the culture tank 14. Therefore, by supplying this hardly decomposable substance into the culture tank 14 by the substrate supply pump 31, the hardly decomposable substance-treated microorganism 4A can be proliferated at high speed.

なお、上記した例は、最終沈殿池５から排出される処理水の一部を培養槽１４に対する基質として流用した例を示したが、予め基質として用いることを前提に人工的に生成したものを培養槽１４に供給する構成とすることもできる。また、この基質は基質供給ポンプ３１を用いなくても、手動により培養槽１４内に投入することは可能である。 In addition, although the above-mentioned example showed the example which diverted a part of the treated water discharged | emitted from the final sedimentation basin 5 as a substrate with respect to the culture tank 14, what was artificially produced | generated previously on the assumption that it uses as a substrate. It can also be set as the structure supplied to the culture tank 14. FIG. Further, this substrate can be manually introduced into the culture tank 14 without using the substrate supply pump 31.

図６は、本発明の第３の実施形態に係る下水処理システムの構成図である。図１の構成では、供給ポンプ２０が培養槽１４から難分解性物質処理微生物４Ａが含まれている培養液１５を反応槽２に供給する構成となっていたが、この第３の実施形態では、最終沈殿池５内に仕切壁３２を設けることにより難分解性物質処理微生物４Ａが生息する領域Ｒ1を形成し、この領域Ｒ1に供給ポンプ２０が培養槽１４からの難分解性物質処理微生物４Ａの供給・補充を行う構成としている。 FIG. 6 is a configuration diagram of a sewage treatment system according to the third embodiment of the present invention. In the configuration of FIG. 1, the supply pump 20 is configured to supply the culture solution 15 containing the hardly degradable substance-treated microorganism 4 </ b> A from the culture vessel 14 to the reaction vessel 2. In the third embodiment , Then, by providing a partition wall 32 in the final sedimentation basin 5, a region R1 where the hardly decomposable substance-treated microorganisms 4A inhabit is formed. Supply and replenishment.

この図６の構成によれば、反応槽２を易分解性物質処理微生物３が主として存在する場所とし、最終沈殿池５の領域Ｒ1を難分解性物質処理微生物４Ａが主として存在する場所であるというように、２種類の微生物を別個の場所に截然と区分することができるので、これら２種類の微生物の管理を容易に行うことができるというメリットがある。 According to the configuration of FIG. 6, the reaction tank 2 is a place where the easily decomposable substance-treated microorganisms 3 are mainly present, and the region R1 of the final sedimentation basin 5 is a place where the hardly degradable substance-treated microorganisms 4A are mainly present. As described above, since the two types of microorganisms can be clearly divided into different places, there is an advantage that these two types of microorganisms can be easily managed.

図７は、本発明の第４の実施形態に係る下水処理システムの構成図である。図７が図１と異なる点は、培養槽１４内の散気管１６にエアを供給するコンプレッサ１７を省略し、その代わりにブロア１２からのエアをバルブ３３を介して散気管１６に供給するようにした点である。このように、１台のブロア１２を反応槽２及び培養槽１４の双方の散気管１０，１６に対して共用することにより、コンプレッサ１７を省略することができると共に、電力消費量を低減することができ省エネルギー化を図ることができる。 FIG. 7 is a configuration diagram of a sewage treatment system according to the fourth embodiment of the present invention. 7 is different from FIG. 1 in that the compressor 17 for supplying air to the air diffuser 16 in the culture tank 14 is omitted, and air from the blower 12 is supplied to the air diffuser 16 via the valve 33 instead. This is the point. Thus, by sharing one blower 12 for the diffuser tubes 10 and 16 of both the reaction tank 2 and the culture tank 14, the compressor 17 can be omitted and the power consumption can be reduced. Can save energy.

この場合、培養槽１４に攪拌機（図示せず）を配設し、その攪拌動作により気泡１８内に含まれる酸素と難分解性物質処理微生物４Ａとの接触を活発に行わせるようにして増殖速度を速くする構成を採用することもできる。また、培養槽１４の上部を密閉構造にして培養槽１４内部を嫌気状態にすることにより、嫌気性の難分解性物質処理微生物４Ａを培養することができる。 In this case, a stirrer (not shown) is provided in the culture tank 14 and the growth rate is such that the oxygen contained in the bubbles 18 and the hardly decomposable substance-treated microorganism 4A are actively contacted by the stirring operation. It is also possible to adopt a configuration that speeds up the operation. Moreover, the anaerobic refractory substance-treated microorganism 4A can be cultured by making the upper part of the culture tank 14 into a sealed structure and making the culture tank 14 anaerobic.

図８は、本発明の第５の実施形態に係る下水処理システムの構成図である。この実施形態は、図１の構成に別の培養槽を追加し、異なる性質を有する難分解性物質処理微生物を反応槽２とは異なる槽に補充するようにしたものである（なお、この図８では、図１において符号４，１４，２０，２４で表されていた構成要素について、「Ａ」を付した符号にすると共に、その名称の頭に「第１の」という文言を付して、同様の機能を有する構成要素の相違を明確にしている。）。 FIG. 8 is a configuration diagram of a sewage treatment system according to the fifth embodiment of the present invention. In this embodiment, another culture tank is added to the configuration of FIG. 1, and a hardly degradable substance-treated microorganism having different properties is replenished to a tank different from the reaction tank 2 (this figure). In FIG. 8, the components represented by reference numerals 4, 14, 20, and 24 in FIG. 1 are changed to reference signs with “A” and the word “first” is added at the beginning of the name. , To clarify the difference between components having similar functions.)

すなわち、最初沈殿池１から反応槽２へ向けて送出される下水の一部が第２の供給ポンプ２４Ｂにより第２の培養槽１４Ｂ内に供給されるようになっている。この下水中には、下水処理場の環境に馴化された第２の難分解性物質処理微生物４Ｂが含まれており、この第２の難分解性物質処理微生物４Ｂを培養槽１４Ｂ内で増殖することができる。そして、第２の供給ポンプ２０Ｂは、この増殖した第２の難分解性物質処理微生物４Ｂを最初沈殿池１内に供給するようになっている。 That is, a part of the sewage that is initially sent from the settling tank 1 toward the reaction tank 2 is supplied into the second culture tank 14B by the second supply pump 24B. The sewage contains a second hardly decomposable substance-treated microorganism 4B adapted to the environment of the sewage treatment plant, and the second hardly degradable substance treated microorganism 4B is propagated in the culture tank 14B. be able to. The second supply pump 20 </ b> B supplies the grown second hardly decomposable substance-treated microorganism 4 </ b> B into the first sedimentation tank 1.

上記の第２の難分解性物質処理微生物４Ｂは、第１の難分解性物質処理微生物４Ａとは異なる機能を有するものである。例えば、第２の難分解性物質処理微生物４Ｂは、セルロースなどの高分子有機物の他に、硫化水素などの無機物も分解する機能を有している。また、嫌気状態活性化機能を有しており、嫌気部が設けられている曝気槽に適用することができる。なお、図８に示した例では、この第２の難分解性物質処理微生物４Ｂを最初沈殿池１の出口付近から採取して第２の培養槽１４Ｂに送りこむ構成を示したが、最初沈殿池１から採取してもよく、あるいは最初沈殿池１の更に上流側に位置するポンプ井や流入渠などから採取する構成とすることもできる。 The second hardly decomposable substance-treated microorganism 4B has a function different from that of the first hardly degradable substance treated microorganism 4A. For example, the second hardly decomposable substance-treated microorganism 4B has a function of decomposing inorganic substances such as hydrogen sulfide in addition to high molecular organic substances such as cellulose. Moreover, it has an anaerobic state activation function and can be applied to the aeration tank in which the anaerobic part is provided. In the example shown in FIG. 8, a configuration is shown in which the second hardly decomposable substance-treated microorganism 4B is collected from the vicinity of the outlet of the first sedimentation tank 1 and sent to the second culture tank 14B. The sample may be collected from 1 or may be collected from a pump well or an inflow basin located further upstream of the first settling basin 1.

図９は、本発明の第６の実施形態に係る下水処理システムの構成図である。図９が図８と異なる点は、第２の供給ポンプ２４Ｂが最終沈殿池５の底部から引き抜かれる処理水の一部を第２の培養槽１４Ｂに供給し、第２の供給ポンプ２０Ｂが、増殖された第２の難分解性物質処理微生物４Ｂを最終沈殿池５に対して補充するようになっている点である。 FIG. 9 is a configuration diagram of a sewage treatment system according to the sixth embodiment of the present invention. 9 differs from FIG. 8 in that the second supply pump 24B supplies a part of the treated water drawn from the bottom of the final sedimentation basin 5 to the second culture tank 14B, and the second supply pump 20B It is the point which supplements the propagated 2nd hardly decomposable substance treatment microorganism 4B with respect to the final sedimentation basin 5. FIG.

但し、図９における第２の難分解性物質処理微生物４Ｂは、図８における微生物４Ｂとは異なる性質を有するものである。この図９における微生物４Ｂは、図４において供給ポンプ２４により培養槽１４に供給される汚泥濃縮槽２５からの濃縮汚泥中に含まれる微生物に近い性質を有するものであり、易分解性物質処理微生物３との共存可能性が大きく、易分解性物質処理微生物３が増殖した汚泥を減量化する機能を有している。 However, the second hardly decomposable substance-treated microorganism 4B in FIG. 9 has different properties from the microorganism 4B in FIG. The microorganism 4B in FIG. 9 has a property close to that of microorganisms contained in the concentrated sludge from the sludge concentration tank 25 supplied to the culture tank 14 by the supply pump 24 in FIG. The coexistence possibility with 3 is large, and it has the function to reduce the sludge which the easily degradable substance processing microorganisms 3 propagated.

図１０は、本発明の第３の参考例に係る下水処理システムの構成図である。この参考例は、図４の構成における汚泥濃縮槽２５から濃縮汚泥以外の水を返流ポンプ３４により最初沈殿池１に返流する構成としたものである。つまり、汚泥濃縮槽２５から濃縮汚泥ポンプ２６を介して汚泥消化槽２７へ送出されるのは濃縮汚泥であり、それ以外の水は、通常、別の水処理系に送出して処理する必要がある。本実施形態では、この濃縮汚泥以外の水成分を最初沈殿池１に戻すようにしている。 FIG. 10 is a configuration diagram of a sewage treatment system according to a third reference example of the present invention. In this reference example, water other than the concentrated sludge is first returned from the sludge concentration tank 25 in the configuration of FIG. That is, it is the concentrated sludge that is sent from the sludge concentration tank 25 to the sludge digestion tank 27 via the concentrated sludge pump 26, and the other water usually needs to be sent to another water treatment system for processing. is there. In this embodiment, water components other than this concentrated sludge are returned to the settling basin 1 first.

そして、この返流される水成分中には、下水よりも高濃度のアンモニア性窒素やリンが存在するので、必ずしも難分解性物質処理微生物とは言えないが、窒素分解機能やリン負荷耐性機能、あるいは低PH耐性機能等を有する微生物が含まれている。したがって、このような微生物を供給ポンプ２０により反応槽２内に送りこむことによって、反応槽２での水処理機能を向上させることができる。 In this returned water component, ammonia nitrogen and phosphorus having a higher concentration than sewage are present, so it cannot necessarily be said to be a hardly-degradable substance-treated microorganism, but the nitrogen decomposition function and phosphorus load resistance function. Or a microorganism having a low PH resistance function or the like. Therefore, the water treatment function in the reaction tank 2 can be improved by feeding such microorganisms into the reaction tank 2 by the supply pump 20.

なお、図１０では、汚泥濃縮槽２５からの水を最初沈殿池１へ返流する構成につき示したが、汚泥消化槽２７又は汚泥脱水機２９からの水を最初沈殿池１へ返流する構成としてもよく、あるいは更に、汚泥濃縮槽２５、汚泥消化槽２７、及び汚泥脱水機２９の全ての槽からの水を最初沈殿池１へ返流する構成としてもよい。 In addition, in FIG. 10, although shown about the structure which returns the water from the sludge concentration tank 25 to the first sedimentation tank 1, the structure which returns the water from the sludge digestion tank 27 or the sludge dehydrator 29 to the first sedimentation tank 1 Alternatively, the water from all the sludge concentration tank 25, the sludge digestion tank 27, and the sludge dehydrator 29 may be first returned to the settling basin 1.

本発明の第１の実施形態に係る下水処理システムの構成図。1 is a configuration diagram of a sewage treatment system according to a first embodiment of the present invention. 図１の反応槽２における難分解性物質に対する処理機能の向上を示す特性図であり、（ａ）は培養槽１４内における難分解性物質処理微生物Ａ４の濃度X1、（ｂ）は反応槽２内における難分解性物質処理微生物４Ａの濃度X2、（ｃ）は河川に放流される放流水に含まれる難分解性物質の濃度S1をそれぞれ示している。It is a characteristic view which shows the improvement of the processing function with respect to the hardly decomposable substance in the reaction tank 2 of FIG. 1, (a) is density | concentration X1 of the hardly decomposable substance processing microbe A4 in the culture tank 14, (b) is the reaction tank 2. The concentration X2 and (c) of the hardly decomposable substance-treated microorganism 4A in the inside indicate the concentration S1 of the hardly decomposable substance contained in the discharged water discharged into the river, respectively. 本発明の第１の参考例に係る下水処理システムの構成図。The block diagram of the sewage treatment system which concerns on the 1st reference example of this invention. 本発明の第２の参考例に係る下水処理システムの構成図。The block diagram of the sewage treatment system which concerns on the 2nd reference example of this invention. 本発明の第２の実施形態に係る下水処理システムの構成図。The block diagram of the sewage treatment system which concerns on the 2nd Embodiment of this invention. 本発明の第３の実施形態に係る下水処理システムの構成図。The block diagram of the sewage treatment system which concerns on the 3rd Embodiment of this invention. 本発明の第４の実施形態に係る下水処理システムの構成図。The block diagram of the sewage treatment system which concerns on the 4th Embodiment of this invention. 本発明の第５の実施形態に係る下水処理システムの構成図。The block diagram of the sewage treatment system which concerns on the 5th Embodiment of this invention. 本発明の第６の実施形態に係る下水処理システムの構成図。The block diagram of the sewage treatment system which concerns on the 6th Embodiment of this invention. 本発明の第３の参考例に係る下水処理システムの構成図。The block diagram of the sewage treatment system which concerns on the 3rd reference example of this invention. 従来例に係る下水処理システムの構成図。The block diagram of the sewage treatment system which concerns on a prior art example. 図１１の構成についての課題を説明するための特性図であり、（ａ）は培養槽１４内における難分解性物質処理微生物４の濃度X1、（ｂ）は反応槽２内における難分解性物質処理微生物４の濃度X2、（ｃ）は河川に放流される放流水に含まれる難分解性物質の濃度S1をそれぞれ示している。FIG. 12 is a characteristic diagram for explaining the problem with the configuration of FIG. 11, (a) is the concentration X1 of the hardly decomposable substance-treated microorganism 4 in the culture tank 14, and (b) is the hardly decomposable substance in the reaction tank 2. The concentration X2 and (c) of the treated microorganism 4 indicate the concentration S1 of the hardly decomposable substance contained in the discharged water discharged into the river.

Explanation of symbols

１最初沈殿池
２反応槽
３易分解性物質処理微生物
４難分解性物質処理微生物
４Ａ第１の難分解性物質処理微生物
４Ｂ第２の難分解性物質処理微生物
５最終沈殿池
６塩素混和池
７水配管
８返送汚泥ポンプ
９余剰汚泥ポンプ
１０散気管
１１バルブ
１２ブロア
１３気泡
１４培養槽
１４Ａ第１の培養槽
１４Ｂ第２の培養槽
１５培養液
１６散気管
１７コンプレッサ
１８気泡
１９基質
２０供給ポンプ
２０Ａ第１の供給ポンプ
２０Ｂ第２の供給ポンプ
２１塩素貯溜槽
２２注入ポンプ
２３底泥
２４供給ポンプ
２４Ａ第１の供給ポンプ
２４Ｂ第２の供給ポンプ
２５汚泥濃縮槽
２６濃縮汚泥ポンプ
２７汚泥消化槽
２８消化汚泥ポンプ
２９汚泥脱水機
３０生汚泥引抜ポンプ
３１基質供給ポンプ
３２仕切壁
３３バルブ
３４返流ポンプ
Ｒ1 領域 DESCRIPTION OF SYMBOLS 1 First sedimentation basin 2 Reaction tank 3 Easily degradable substance processing microorganism 4 Refractory substance treatment microorganism 4A 1st refractory substance treatment microorganism 4B 2nd refractory substance treatment microorganism 5 Final sedimentation tank 6 Chlorine mixing pond 7 Water pipe 8 Return sludge pump 9 Surplus sludge pump 10 Aeration pipe 11 Valve 12 Blower 13 Bubble 14 Culture tank 14A First culture tank 14B Second culture tank 15 Culture solution 16 Aeration pipe 17 Compressor 18 Bubble 19 Substrate 20 Supply pump 20A First supply pump 20B Second supply pump 21 Chlorine reservoir 22 Injection pump 23 Bottom mud 24 Supply pump 24A First supply pump 24B Second supply pump 25 Sludge concentration tank 26 Concentrated sludge pump 27 Sludge digestion tank 28 Digestion Sludge pump 29 Sludge dewatering machine 30 Raw sludge extraction pump 31 Substrate supply pump 32 Partition wall 33 Valve 34 Return pump R1 Pass

Claims

There are microorganisms that are treated with difficult-to-decompose substances together with microorganisms that are treated with easily-degradable substances. The degradation and assimilation functions of these microorganisms with treated with degradable substances can be used to remove the substances that are difficult to degrade. A reaction vessel to perform,
When the refractory substance-treated microorganism is cultured, and the refractory substance-treated microorganism in the reaction tank is reduced, a culture tank that replenishes the reaction tank with the refractory substance-treated microorganism;
In a sewage treatment system with
Includes river bottom mud where conditioned refractory substance-treated microorganisms exist from a location located downstream of the reaction tank and near a discharge port for discharging discharged water to a river outside the system. Conditioned microorganism reflux means for refluxing water to the culture tank,
A sewage treatment system characterized by that.

Provided with a substrate supply means for supplying the artificially generated substrate or supplying the substrate as a substrate of a hardly decomposable substance collected from a predetermined location inside the system,
The sewage treatment system according to claim 1 .

A final sedimentation basin is installed on the downstream side of the reaction tank, and the hardly decomposable substance-treated microorganism is present in a partial region of the final sedimentation basin, and the persistent degradation is cultured in the culture tank Replenishment of the substance-treated microorganism was performed on the final sedimentation basin instead of the reaction tank.
The sewage treatment system according to claim 1 .

In the reaction tank and the culture tank, a diffuser pipe for supplying external air to each sewage and culture solution is provided, and the supply of external air to both the diffuser pipes is performed by one blower. To share,
The sewage treatment system according to any one of claims 1 to 3 .

The hardly degradable substance-treated microorganism present in the reaction tank is the first hardly degradable substance treated microorganism, the culture tank for culturing the first hardly degradable substance treated microorganism is the first culture tank, and the reflux means. When the first reflux means is used,
A first sedimentation basin is installed upstream of the reaction tank, and a second culture tank for culturing the second persistent substance-treated microorganism existing in the first sedimentation basin is installed. A second reflux means for refluxing the water containing the second persistent substance-treated microorganism conditioned from a nearby location to the second culture tank;
The second refractory substance-treated microorganism is replenished to the first sedimentation basin by the second reflux means.
A sewage treatment system according to any one of claims 1 to 4 .

The hardly degradable substance-treated microorganism present in the reaction tank is the first hardly degradable substance treated microorganism, the culture tank for culturing the first hardly degradable substance treated microorganism is the first culture tank, and the reflux means. When the first reflux means is used,
A final sedimentation basin is installed on the downstream side of the reaction tank, and a second culture tank for culturing the second hardly decomposable substance-treated microorganism existing in the final sedimentation basin is installed. A second reflux means for refluxing the water containing the second persistent substance-treated microorganism conditioned from a nearby location to the second culture tank;
Replenishing the final sedimentation basin with the second persistent substance-treated microorganism by the second reflux means;
A sewage treatment system according to any one of claims 1 to 4 .