JP2003001284A - Method for cleaning water and device therefor - Google Patents
Method for cleaning water and device thereforInfo
- Publication number
- JP2003001284A JP2003001284A JP2001191567A JP2001191567A JP2003001284A JP 2003001284 A JP2003001284 A JP 2003001284A JP 2001191567 A JP2001191567 A JP 2001191567A JP 2001191567 A JP2001191567 A JP 2001191567A JP 2003001284 A JP2003001284 A JP 2003001284A
- Authority
- JP
- Japan
- Prior art keywords
- water
- entrapping immobilization
- treated
- microorganisms
- immobilization pellets
- 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.)
- Pending
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/10—Biological treatment of water, waste water, or sewage
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、例えば湖沼、池、
ダム、溜池、貯水池、河川、用水路、堀、運河、水槽、
地下水などの好気条件の被処理水を生物学的に処理する
包括固定化担体を用いた水質浄化方法、および水質浄化
装置に関する。TECHNICAL FIELD The present invention relates to lakes, ponds,
Dam, reservoir, reservoir, river, canal, moat, canal, tank,
The present invention relates to a water purification method and a water purification apparatus using an entrapping immobilization carrier that biologically treats water to be treated under aerobic conditions such as groundwater.
【０００２】[0002]
【従来の技術】従来、生物学的窒素除去を行う水質浄化
装置としては、微生物を固定化した包括固定化担体に好
気条件または嫌気条件の被処理水を導入し、包括固定化
担体の微生物を用いて被処理水を浄化するものがある。
この場合、包括固定化担体としては、硝化菌（好気性微
生物）、脱窒菌（嫌気性微生物）などの微生物をゲル状
固定化材などの固定化材に固定化し、粒径３〜５ｍｍ程
度に成形したものが多く用いられている。この水質浄化
装置を用いて硝化反応を生じさせて被処理水の浄化を行
うには、被処理水を好気条件とし、包括固定化担体の好
気性微生物による浄化処理を行わせる。また、この水質
浄化装置を用いて脱窒反応による窒素除去処理を行うに
は、被処理水を嫌気条件とし、包括固定化担体の嫌気性
微生物による脱窒作用によって、被処理水中の窒素（硝
酸態窒素）を窒素ガスに変換する。なお、硝化反応は、
通常、以下に示す式（１）に従って進行する。2. Description of the Related Art Conventionally, as a water purification apparatus for removing biological nitrogen, the water to be treated under aerobic or anaerobic conditions is introduced into an entrapping immobilization carrier on which microorganisms are immobilized, and microorganisms on the entrapping immobilization carrier are introduced. There is one that purifies the water to be treated using.
In this case, as the entrapping immobilization carrier, microorganisms such as nitrifying bacteria (aerobic microorganisms) and denitrifying bacteria (anaerobic microorganisms) are immobilized on an immobilizing material such as a gel immobilizing material to have a particle size of about 3 to 5 mm. Molded products are often used. In order to purify the water to be treated by causing a nitrification reaction using this water purification apparatus, the water to be treated is subjected to aerobic conditions and the entrapping immobilization pellets are subjected to a purification treatment with aerobic microorganisms. Further, in order to perform nitrogen removal treatment by a denitrification reaction using this water purification device, the water to be treated is subjected to anaerobic conditions, and the denitrification action of the entrapping immobilization carrier by the anaerobic microorganisms causes nitrogen (nitric acid) Converted nitrogen) to nitrogen gas. The nitrification reaction is
Usually, the process proceeds according to the following formula (1).
【化１】
また、脱窒反応は、通常、以下に示す式（２）に従って
進行する。[Chemical 1] The denitrification reaction usually proceeds according to the following equation (2).
【化２】 [Chemical 2]
【０００３】[0003]
【発明が解決しようとする課題】上記従来の水質浄化装
置では、好気条件の被処理水において脱窒反応を行わせ
て浄化を行う場合、この被処理水を嫌気条件にする必要
がある。このため、従来は、好気条件の被処理水を嫌気
条件とするために脱気装置を用いることも行われている
が、この場合には装置コストがかさむ問題がある。ま
た、嫌気条件の被処理水において硝化反応を行わせて浄
化を行う場合には、被処理水を好気条件とするために曝
気装置を用いられることも行われているが、この場合に
も装置コストがかさむ問題がある。本発明は、上記事情
に鑑みてなされたもので、好気条件の被処理水を単一の
包括固定化担体を用いて硝化反応と脱窒反応との両反応
を生じさせることにより好気条件の被処理水を効率良く
浄化できる水質浄化方法及びその装置を提供することを
目的とする。In the above-mentioned conventional water purification apparatus, when the denitrification reaction is performed on the water to be treated under aerobic conditions for purification, the water to be treated needs to be under anaerobic conditions. For this reason, conventionally, a deaerator has been used to bring the water to be treated under aerobic conditions into an anaerobic condition, but in this case, there is a problem that the cost of the device is high. Further, when purifying by performing a nitrification reaction in the treated water under anaerobic conditions, an aeration device is often used to bring the treated water into an aerobic condition. There is a problem that the device cost is high. The present invention has been made in view of the above circumstances, and aerobically treated water under aerobic conditions is subjected to both a nitrification reaction and a denitrification reaction by using a single entrapping immobilization carrier. It is an object of the present invention to provide a water quality purification method and apparatus capable of efficiently purifying water to be treated.
【０００４】[0004]
【課題を解決するための手段】請求項１の発明は、微生
物を固定化剤により固定化した包括固定化担体により、
好気条件の被処理水を浄化する水質浄化方法であって、
前記包括固定化担体は、前記好気条件下において、外側
部分が好気条件になり、かつ、内側部分が嫌気条件とな
る大きさを有することを特徴とする。請求項２の発明
は、微生物を固定化剤により固定化した包括固定化担体
により、好気条件の被処理水を浄化する水質浄化方法で
あって、前記包括固定化担体の最短径が７．５ｍｍ以上
１００ｍｍ以下の大きさであることを特徴とする。請求
項３の発明は、微生物を固定化剤により固定化した包括
固定化担体が収納された浄化体に好気条件の被処理水を
導入することにより当該被処理水を浄化する水質浄化装
置であって、前記包括固定化担体は、前記好気条件下に
おいて、外側部分が好気条件になり、かつ、内側部分が
嫌気条件となる大きさを有することを特徴とする。請求
項４の発明は、微生物を固定化剤により固定化した包括
固定化担体が収納された浄化体に好気条件の被処理水を
導入することにより当該被処理水を浄化する水質浄化装
置であって、前記包括固定化担体の最短径が７．５ｍｍ
以上１００ｍｍ以下の大きさであることを特徴とする。According to the invention of claim 1, an entrapping immobilization carrier in which a microorganism is immobilized by an immobilizing agent is used.
A method for purifying water under aerobic conditions, comprising:
The entrapping immobilization pellets are characterized in that, under the aerobic conditions, the outer part has an aerobic condition and the inner part has an anaerobic condition. The invention of claim 2 is a water purification method for purifying water to be treated under aerobic conditions by a comprehensive immobilization carrier in which microorganisms are immobilized by an immobilizing agent, wherein the shortest diameter of the comprehensive immobilization carrier is 7. It is characterized by having a size of 5 mm or more and 100 mm or less. The invention of claim 3 is a water purification apparatus for purifying the water to be treated by introducing the water to be treated under aerobic conditions into the purification body in which the entrapping immobilization carrier in which the microorganisms are immobilized by the immobilizing agent is stored. Then, the entrapping immobilization pellets are characterized in that they have a size such that, under the aerobic conditions, the outer part is an aerobic condition and the inner part is an anaerobic condition. The invention according to claim 4 is a water purification apparatus for purifying the water to be treated by introducing the water to be treated under aerobic conditions into the purification body in which the entrapping immobilization pellets in which microorganisms are immobilized by an immobilizing agent are stored. Therefore, the shortest diameter of the entrapping immobilization pellets is 7.5 mm
It is characterized in that the size is 100 mm or less.
【０００５】[0005]
【発明の実施の形態】図１は、本発明の水質浄化装置の
一実施形態に用いられる包括固定化担体を示すもので、
ここに示す包括固定化担体１は、 微生物をゲル状固定
化剤（固定化剤）により固定化して得られたものであ
る。包括固定化担体１は、上記微生物源（活性汚泥等）
と、未硬化のゲル状固定化剤（例えば単量体のエチレン
グリコール）とを混合した後、この未硬化ゲル状固定化
剤を、重合、架橋などにより硬化（ゲル化）させること
によって作製することができる。未硬化のゲル状固定化
剤を硬化させる際には、必要に応じて架橋剤、重合促進
剤、重合開始剤などを添加することができる。また、ゲ
ル状固定化剤としては、ポリエチレングリコール系樹
脂、ポリビニルアルコール系樹脂、ポリアクリルアミド
系樹脂、アルギン酸塩、カラギーナン、寒天などを用い
ることができる。なかでも特に、ポリエチレングリコー
ルを含む材料を用いるのが好ましい。ポリエチレングリ
コールを含む材料を用いる場合には、ポリエチレングリ
コールの含有率を１０〜１５重量％とするのが好まし
い。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an entrapping immobilization pellets used in an embodiment of the water purification apparatus of the present invention.
The entrapping immobilization pellets 1 shown here are obtained by immobilizing microorganisms with a gel-like immobilizing agent (immobilizing agent). The comprehensive immobilization carrier 1 is a source of the above microorganisms (activated sludge, etc.)
And an uncured gel-like immobilizing agent (for example, monomeric ethylene glycol) are mixed, and then the uncured gel-like immobilizing agent is cured (gelled) by polymerization, crosslinking, or the like. be able to. When curing the uncured gel-like fixing agent, a crosslinking agent, a polymerization accelerator, a polymerization initiator and the like can be added as necessary. As the gel-like fixing agent, polyethylene glycol-based resin, polyvinyl alcohol-based resin, polyacrylamide-based resin, alginate, carrageenan, agar or the like can be used. Especially, it is preferable to use a material containing polyethylene glycol. When using a material containing polyethylene glycol, the content of polyethylene glycol is preferably 10 to 15% by weight.
【０００６】包括固定化担体１内への微生物の固定化
は、活性汚泥や対称水域の底泥に生息する微生物を、こ
の底泥ごと固定化させることにより行なわれる。なお、
予め脱窒菌の生育に適した環境下（例えば硝酸態窒素お
よび炭素源が豊富に存在する嫌気条件下）において馴化
した活性汚泥ごと固定化しても良く、また純粋培養され
た脱窒菌のみを固定化しても良い。また、固定化する微
生物は脱窒菌以外の微生物でも良く、例えば、藻類の発
生が著しい水域では溶藻菌などの微生物を固定化すれ
ば、水質に最適な微生物を用いて浄化を行なうこともで
きる。この微生物源の使用量は、包括固定化担体１中の
微生物の含有率が０．１〜１０重量％以上（好ましくは
約２重量％）となるように設定するのが好ましい。The immobilization of the microorganisms in the entrapping immobilization pellets 1 is carried out by immobilizing the microorganisms inhabiting the activated sludge and the bottom mud in the symmetrical water area together with the bottom mud. In addition,
The activated sludge that has been acclimated in advance in an environment suitable for the growth of denitrifying bacteria (for example, under anaerobic conditions rich in nitrate nitrogen and carbon sources) may be immobilized, or only purely cultured denitrifying bacteria may be immobilized. May be. In addition, the microorganisms to be immobilized may be microorganisms other than denitrifying bacteria, for example, by immobilizing microorganisms such as lytic bacteria in water areas where algae are significantly generated, it is possible to perform purification using microorganisms most suitable for water quality. . The amount of the microorganism source used is preferably set so that the content of the microorganisms in the entrapping immobilization pellets 1 is 0.1 to 10% by weight or more (preferably about 2% by weight).
【０００７】本実施形態において、包括固定化担体１
は、これを用いて好気条件の被処理水を脱窒処理する際
に、内側部分４が嫌気条件となるように構成されてい
る。ここで、好気条件とは溶存酸素濃度が２mg／L以上
である被処理水であることを指し、嫌気条件とは、溶存
酸素濃度が２mg／L未満である被処理水であることを指
す。すなわち、図１に示すように、包括固定化担体１
は、好気条件の被処理水２中において、被処理水２中の
酸素が、拡散により包括固定化担体１の外側部分３に至
るものの、内側部分４には達しないように構成されてい
る。このため、包括固定化担体１は、外側部分３が好気
条件となり、内側部分４が嫌気条件となる。In this embodiment, the entrapping immobilization pellets 1
Is configured such that the inner portion 4 is in an anaerobic condition when denitrifying the water to be treated under aerobic conditions using this. Here, the aerobic condition means that the treated water has a dissolved oxygen concentration of 2 mg / L or more, and the anaerobic condition means that the treated oxygen has a dissolved oxygen concentration of less than 2 mg / L. . That is, as shown in FIG. 1, the entrapping immobilization pellets 1
Is configured such that, in the water 2 to be treated under aerobic conditions, oxygen in the water 2 to be treated reaches the outer portion 3 of the entrapping immobilization pellets 1 by diffusion, but does not reach the inner portion 4. . Therefore, in the entrapping immobilization pellets 1, the outer portion 3 is in an aerobic condition and the inner portion 4 is in an anaerobic condition.
【０００８】図２は、好気条件（溶存酸素濃度が２ｍｇ
／L以上）の被処理水を包括固定化担体１に供給した場
合の、包括固定化担体１の粒径の最短径の違いによる内
部構造の違いを模式的に示す図である。図２(A)は、包
括固定化担体１の粒径の最短径が７．５ｍｍ未満の場合
を、図２(B)は７．５ｍｍ以上１００ｍｍ以下の場合
を、図２(C)は１００ｍｍを超えた場合の包括固定化担
体１の内部の状態を示している。ここで、包括固定化担
体１の最短径とは、包括固定化担体１の粒径の一番短い
部分の長さをいい、例えば球状の担体であれば直径を指
し、直方体形状の担体であれば、短径のことを指す。図
２(A)に示される様に、最短径が７．５ｍｍ未満の包括
固定化担体１では、被処理水２中の酸素が、拡散により
包括固定化担体１の内側部分にまで硝化反応に利用され
きれずに浸透するため、包括固定化担体１内部に嫌気部
分を形成することができない。図２(B)に示される様
に、最短径を７．５ｍｍよりも大粒径とした場合には、
包括固定化担体１の内側部分４に嫌気部分が生じる。こ
れは、包括固定化担体１の最短径を７．５mm以上にして
いくと、被処理水２中の酸素は、包括固定化担体１の外
側部分３で硝化反応により消費されるからである。包括
固定化担体１の内側部分４に嫌気部分が形成されること
によって、内側部分４における脱窒反応効率を高めるこ
とができるようになる。そして、包括固定化担体１の粒
径の最短径を更に大きくしていくと、図２(C)に示され
る様に１００mmを超えたところで、内側部分４内に硝化
反応と脱窒反応とのいずれの反応にも使われない中央部
分５が生じることにより、単位体積当たりの処理効率が
低くなる。これは、包括固定化担体１の中央部分５に被
処理物質（硝酸態窒素等）が浸透しにくくなるためであ
る。従って、包括固定化担体１の最短径は、７．５ｍｍ
以上１００ｍｍ以下とするのが好ましい。好ましくは、
担体１の最短径は、１０ｍｍ以上１００ｍｍ以下とする
のがよく、２０ｍｍ以上７０ｍｍ以下とするのがより好
ましく、３０ｍｍ以上５０ｍｍ以下とするのがさらに好
ましい。FIG. 2 shows aerobic conditions (dissolved oxygen concentration is 2 mg).
FIG. 5 is a diagram schematically showing a difference in internal structure due to a difference in the shortest particle diameter of the entrapping immobilization pellets 1 when water to be treated (/ L or more) is supplied to the entrapping immobilization pellets 1. FIG. 2 (A) shows the case where the shortest particle diameter of the entrapping immobilization pellets 1 is less than 7.5 mm, FIG. 2 (B) shows the case of 7.5 mm or more and 100 mm or less, and FIG. 2 (C) shows 100 mm. The figure shows the internal state of the entrapping immobilization pellets 1 in the case of exceeding. Here, the shortest diameter of the entrapping immobilization pellets 1 refers to the length of the shortest particle size of the entrapping immobilization pellets 1, for example, a spherical pellet refers to the diameter, and may be a rectangular parallelepiped pellet. For example, it refers to the short diameter. As shown in FIG. 2 (A), in the entrapping immobilization pellets 1 having the shortest diameter of less than 7.5 mm, the oxygen in the water 2 to be treated is diffused to the inner part of the entrapping immobilization pellets 1 for nitrification reaction. An anaerobic part cannot be formed inside the entrapping immobilization pellets 1 because it penetrates without being utilized. As shown in Fig. 2 (B), when the shortest diameter is larger than 7.5 mm,
An anaerobic portion is generated in the inner portion 4 of the entrapping immobilization pellets 1. This is because when the shortest diameter of the entrapping immobilization pellets 1 is 7.5 mm or more, oxygen in the water 2 to be treated is consumed by the nitrification reaction in the outer portion 3 of the entrapping immobilization pellets 1. By forming an anaerobic part in the inner part 4 of the entrapping immobilization pellets 1, the denitrification reaction efficiency in the inner part 4 can be improved. When the shortest diameter of the entrapping immobilization pellets 1 is further increased, the nitrification reaction and the denitrification reaction occur in the inner portion 4 when the diameter exceeds 100 mm as shown in FIG. Since the central portion 5 which is not used in any of the reactions is generated, the processing efficiency per unit volume is lowered. This is because the substance to be treated (nitrate nitrogen, etc.) hardly penetrates into the central portion 5 of the entrapping immobilization pellets 1. Therefore, the shortest diameter of the comprehensive immobilization carrier 1 is 7.5 mm.
It is preferably 100 mm or less. Preferably,
The shortest diameter of the carrier 1 is preferably 10 mm or more and 100 mm or less, more preferably 20 mm or more and 70 mm or less, and further preferably 30 mm or more and 50 mm or less.
【０００９】図３は、本発明の水質浄化装置の一実施形
態を示すもので、ここに示す水質浄化装置９は、最短径
が７．５ｍｍ〜１００ｍｍの範囲内の粒径を有する包括
固定化担体１と、この包括固定化担体１が収納された密
閉容器６とからなる浄化体７と、該浄化体７内に好気条
件の被処理水２を導入するポンプ８とから構成されてい
る。なお、本実施形態では密閉容器６を用いたが、一部
開放している容器を用いてもよいのは、もちろんであ
る。浄化体７は、その上面と下面を板状の上下板部１
０、１１で密閉し、該上下板部１０、１１には被処理水
１をポンプ７により浄化体６内に給送するための図示せ
ぬ管路、及び排水のための図示せぬ管路が設けられてい
る。ここで、包括固定化担体１は浄化体７内に包括固定
化担体１が流動することないよう詰められ、これにより
固定床が形成されている。浄化体７内に包括固定化担体
１を固定的に設けることにより、流動床と比して再曝気
による溶存酸素濃度の増加を防ぐことができる。また、
被処理水２の給水口近傍と比して排水口に近づくにつ
れ、溶存酸素濃度が低くなるため、浄化体７の排水口近
傍では、より脱窒反応を起こしやすい条件とすることが
できる。浄化体７内部に給送された被処理水１は、重な
り合った包括固定化担体１の隙間部を通過し、浄化体７
下面に設けられた図示せぬ排水管路より系外に排出され
る。FIG. 3 shows an embodiment of the water purification apparatus of the present invention. In the water purification apparatus 9 shown here, entrapping immobilization having a particle diameter within the range of the shortest diameter of 7.5 mm to 100 mm is carried out. It is composed of a carrier 1, a purification body 7 including a closed container 6 accommodating the entrapping immobilization carrier 1, and a pump 8 for introducing the water 2 to be treated under aerobic conditions into the purification body 7. . Although the closed container 6 is used in the present embodiment, it goes without saying that a partially opened container may be used. The purifying body 7 has a plate-like upper and lower plate portion 1 whose upper and lower surfaces are
0 and 11, and a pipe line (not shown) for feeding the water to be treated 1 into the purifying body 6 by the pump 7 and a pipe line for draining water to the upper and lower plate parts 10, 11. Is provided. Here, the entrapping immobilization pellets 1 are packed in the purifying body 7 so that the entrapping immobilization pellets 1 do not flow, thereby forming a fixed bed. By fixing the entrapping immobilization pellets 1 in the purification body 7, it is possible to prevent an increase in the dissolved oxygen concentration due to re-aeration as compared with the fluidized bed. Also,
Since the dissolved oxygen concentration becomes lower as the treated water 2 is closer to the drainage port as compared to the vicinity of the water supply port of the water to be treated 2, it can be set as a condition in which the denitrification reaction is more likely to occur near the drainage port of the purification body 7. The water to be treated 1 fed into the purifying body 7 passes through the gap between the entrapping immobilization pellets 1 that overlap with each other, and the purifying body 7
It is discharged to the outside of the system from a drainage pipe (not shown) provided on the lower surface.
【００１０】以下、浄化体７内部における被処理水２の
浄化処理過程を詳しく説明する。浄化体７内部に流入し
た被処理水２中のアンモニア態窒素は、包括固定化担体
１の外側部分３に硝化菌や他の従属栄養菌などの好気性
微生物を付着、繁殖させる。ここで、包括固定化担体１
には好気性従属栄養素菌、硝化菌、脱窒菌などの微生物
が固定化されている。被処理水２中に含まれている除去
対象となる有機物及び窒素成分は包括固定化担体１に供
給される。供給された有機物及び窒素成分は包括固定化
担体１に固定的に設けられている微生物と接触すること
により分解、除去される。包括固定化担体の粒径の最短
径は、７．５ｍｍ以上１００ｍｍ以下の大きさを有して
いるため、被処理水２中の酸素は、包括固定化担体１の
外側部分３の好気性微生物により消費され、内側部分４
には達しない。このため、包括固定化担体１は、外側部
分３が好気条件となり、内側部分４が嫌気条件となる。
ここで被処理水２の浄化の過程について説明する。ま
ず、被処理水２中のアンモニア態窒素は、包括固定化担
体１の外側部分３の硝化菌により式（１）に示すように
硝化され、硝酸態窒素となる。The purification process of the water to be treated 2 inside the purification body 7 will be described in detail below. The ammonia nitrogen in the water to be treated 2 that has flowed into the purification body 7 causes aerobic microorganisms such as nitrifying bacteria and other heterotrophic bacteria to adhere and propagate on the outer portion 3 of the entrapping immobilization pellets 1. Here, the comprehensive immobilization carrier 1
Microorganisms such as aerobic heterotrophic bacteria, nitrifying bacteria, and denitrifying bacteria are immobilized on the. Organic substances and nitrogen components to be removed which are contained in the water to be treated 2 are supplied to the entrapping immobilization pellets 1. The supplied organic matter and nitrogen component are decomposed and removed by contacting the microorganisms fixedly provided on the entrapping immobilization pellets 1. Since the shortest diameter of the entrapping immobilization pellets is 7.5 mm or more and 100 mm or less, oxygen in the water 2 to be treated is aerobic microorganisms in the outer portion 3 of the entrapping immobilization pellets 1. Consumed by the inner part 4
Does not reach Therefore, in the entrapping immobilization pellets 1, the outer portion 3 is in an aerobic condition and the inner portion 4 is in an anaerobic condition.
Here, the process of purifying the treated water 2 will be described. First, the ammonia nitrogen in the water to be treated 2 is nitrified by the nitrifying bacteria in the outer portion 3 of the entrapping immobilization pellets 1 as shown in formula (1) to become nitrate nitrogen.
【化３】
被処理水中の硝酸態窒素は、外側部分３では除去されず
に、担体１内に浸入し、拡散により内側部分４に達す
る。よって、好気条件の外側部分３では脱窒反応が起こ
らないものの、嫌気条件となる内側部分４において、被
処理水中の硝酸態窒素が、式（２）に示す脱窒反応によ
り還元され、窒素ガスとなる。[Chemical 3] The nitrate nitrogen in the water to be treated is not removed by the outer portion 3 but penetrates into the carrier 1 and reaches the inner portion 4 by diffusion. Therefore, although the denitrification reaction does not occur in the outer part 3 under aerobic conditions, the nitrate nitrogen in the water to be treated is reduced by the denitrification reaction shown in the formula (2) in the inner part 4 under anaerobic conditions, and It becomes gas.
【化４】 [Chemical 4]
【００１１】このように、被処理水２が浄化体６を通過
する過程で、被処理水２中の窒素成分及び有機物は除去
され、低窒素濃度の処理水を得ることができる。As described above, in the process of the treated water 2 passing through the purifying body 6, the nitrogen component and the organic matter in the treated water 2 are removed, and the treated water having a low nitrogen concentration can be obtained.
【００１２】以上のように、包括固定化担体１は、被処
理水２の溶存酸素濃度が２ｍｇ／L以上（好ましくは５
〜７mg／L）の好気条件下において、包括固定化担体１
の最短径を７．５ｍｍ〜１００ｍｍの範囲内とすること
により、担体の外側部分３は好気条件、内側部分４は嫌
気条件となる。つまり、包括固定化担体１の外側部分３
には好気性微生物が、包括固定化担体１の内側部分４に
は嫌気性の微生物が生息するようになるので、被処理水
２が好気条件である場合でも、担体１の内側部分４にお
いて嫌気条件下で脱窒反応を進行させ、低窒素濃度の処
理水を得ることができる。また、１つの包括固定化担体
１で好気−嫌気処理を同時に起こすことができる。よっ
て、好気条件である被処理水の脱窒反応を促すことがで
きるため、脱気装置を用いる必要がなく、設備コストを
低く抑えることができる。As described above, the entrapping immobilization pellets 1 have a dissolved oxygen concentration of the water 2 to be treated of 2 mg / L or more (preferably 5).
~ 7 mg / L) under aerobic conditions, entrapping immobilization pellets 1
By setting the shortest diameter of the carrier to be in the range of 7.5 mm to 100 mm, the outer part 3 of the carrier is aerobic and the inner part 4 is anaerobic. That is, the outer portion 3 of the comprehensive immobilization carrier 1
Since the aerobic microorganisms and the anaerobic microorganisms inhabit the inner portion 4 of the entrapping immobilization carrier 1, even in the aerobic condition of the treated water 2, the inner portion 4 of the carrier 1 The denitrification reaction can proceed under anaerobic conditions to obtain treated water with a low nitrogen concentration. Further, one entrapping immobilization pellets 1 can simultaneously perform aerobic-anaerobic treatment. Therefore, the denitrification reaction of the water to be treated, which is an aerobic condition, can be promoted, so that it is not necessary to use a deaerator, and the equipment cost can be kept low.
【００１３】また一般に、窒素除去処理において硝化反
応が抑制されると、硝化反応の中間体であるＮＯＨ（式
（１）を参照）に由来する温室効果ガスであるＮ2Ｏの
発生量が増大することがあることが知られている。上記
担体１では、内側部分４において嫌気条件下で脱窒処理
を効率よく行うことができるため、担体外側部分３で生
成した硝酸態窒素は、滞ることなく直ちに脱窒処理され
る。この様に前記式（１）に示す反応が逐次的に起こる
ので、中間生成物ＮＯＨの濃度を低く維持し、Ｎ2Ｏの
生成を抑制し、温室効果による環境悪化を最小限に抑え
ることができる。In general, when the nitrification reaction is suppressed in the nitrogen removal treatment, the amount of greenhouse gas N 2 O derived from NOH (see equation (1)), which is an intermediate of the nitrification reaction, increases. It is known to do. In the carrier 1, since the denitrification treatment can be efficiently performed in the inner portion 4 under anaerobic conditions, the nitrate nitrogen generated in the carrier outer portion 3 is immediately denitrified without delay. Since the reaction represented by the above formula (1) occurs sequentially in this manner, the concentration of the intermediate product NOH can be kept low, the production of N 2 O can be suppressed, and the environmental deterioration due to the greenhouse effect can be minimized. it can.
【００１４】[0014]
【実施例】以下、具体例を示して本発明の効果を明確に
する。図４に本発明の効果を明確にするための試験装置
２１を示す。該試験装置２１は、実際の水質浄化装置を
模擬した装置である。ビーカー１２内に針金１３等でビ
ーカー１２上部につるした金網１４の内部に、包括固定
化担体１を充填させる。なお、該金網１４は、内部に充
填させる包括固定化担体１よりも小さい網目を有するも
のを用いる。ビーカー１２底部にはビーカー１２内の水
に常に酸素を供給し続けるため、撹拌子１５を設置す
る。撹拌子１５は、ビーカー１２内の被処理水２の溶存
酸素濃度を調節するために用いる。例えば溶存酸素濃度
を常に７ｍｇ／Lとするためには、撹拌子１５の撹拌速
度は２００〜５００rpmとする。試験装置２１に用いる
包括固定化担体１は活性汚泥を固定化剤にポリマを用い
て包括固定させる。その際、ポリマ濃度は１０〜１５
％、微生物の濃度は２％、担体充填量は１Lとする。ま
た、被処理水量は５Lとし、試験を行なう。
（試験例１）硝酸態窒素を含む被処理水を、試験装置２
１を用いて浄化処理した。金網１４内に充填させる包括
固定化担体１の最短径を３ｍｍとした時と、３〜５ｃｍ
とした時の２通りにおいて、ビーカー１２内の溶存酸素
濃度を変化させた時の試験開始後、一定時間後の窒素除
去率を求めた。試験結果を、溶存酸素濃度と、窒素除去
率との関係を示すグラフである図５を用いて説明する。
溶存酸素濃度が０〜１mg／Lの範囲であるとき、窒素除
去率はどちらも１００％であるが、溶存酸素濃度が１ｍ
ｇ／Lを超えたところで、包括固定化担体１の最短径が
３ｍｍの被処理水２の窒素除去率が大幅に低下し始める
のに対し、包括固定化担体１の最短径が３〜５ｃｍの被
処理水２の窒素除去率は多少低下し始めるものの、９０
％以上の窒素除去率を維持する。上記結果を考察する
と、包括固定化担体１の最短径が３〜５ｃｍと大きい担
体は、被処理水２中の窒素成分に含まれる酸素を包括固
定化担体１の外側部分３で好気性微生物により消費さ
せ、担体内側部分に嫌気部分を形成させることにより脱
窒反応を起こす事ができたと考えられる。包括固定化担
体１の最短径が３ｍｍと小さい担体は、嫌気条件下、つ
まり溶存酸素濃度が０〜２ｍｇ／Lの範囲内において
は、嫌気脱窒処理が可能であったが、好気条件下におい
ては、溶存酸素濃度が高いため、包括固定化担体１の内
側部分で酸素を消費することができず、嫌気部分を形成
させることができなかったと考えられる。
（試験例２）図６は、溶存酸素濃度を７ｍｇ／Lに固定
しておき、包括固定化担体１の最短径を変化させた場合
の試験開始後、一定時間後の窒素除去率を示すグラフで
ある。同図に示される様に、包括固定化担体１の最短径
が７．５ｍｍ未満の大きさの包括固定化担体１は、担体
内で嫌気部分を作ることができず、窒素除去率が低い。
また、包括固定化担体１の最短径が、７．５ｍｍのとこ
ろから窒素除去率が増加していることがわかる。これ
は、酸素成分が担体外側部分３で消費され、嫌気部分が
担体内側部分４に生じ、そこで脱窒反応が行なわれてい
ると解釈できる。つぎに、包括固定化担体１の最短径を
さらに大きくしていくと、最短径が約４ｃｍのところで
窒素除去率が最大となり、その後は最短径が大きくなる
につれて、窒素除去率が低下しているのがわかる。これ
は、最短径を大きくすると、包括固定化担体１の中央部
分５にまで被処理物質（硝酸態窒素等）が浸透しにくく
なるため、嫌気部分を形成しているにもかかわらず、脱
窒をおこなえない、つまり反応に使われない部分が形成
されることになり、結果として、窒素除去率が低下する
ことになるためと考えられる。EXAMPLES Hereinafter, the effects of the present invention will be clarified by showing concrete examples. FIG. 4 shows a test apparatus 21 for clarifying the effect of the present invention. The test device 21 is a device simulating an actual water purification device. The entrapping immobilization pellets 1 are filled into the inside of the wire net 14 suspended above the beaker 12 by the wire 13 or the like in the beaker 12. The wire mesh 14 has a mesh smaller than that of the entrapping immobilization pellets 1 to be filled inside. A stir bar 15 is installed at the bottom of the beaker 12 in order to constantly supply oxygen to the water in the beaker 12. The stirrer 15 is used to adjust the dissolved oxygen concentration of the water 2 to be treated in the beaker 12. For example, in order to always maintain the dissolved oxygen concentration at 7 mg / L, the stirring speed of the stirrer 15 is set to 200 to 500 rpm. The entrapping immobilization pellets 1 used in the test apparatus 21 entraps and fixes activated sludge by using a polymer as an immobilizing agent. At that time, the polymer concentration is 10 to 15
%, The concentration of microorganisms is 2%, and the carrier filling amount is 1L. The amount of water to be treated is 5L and the test is conducted. (Test Example 1) A test device 2 was used to treat water to be treated containing nitrate nitrogen.
1 was used for purification treatment. When the shortest diameter of the entrapping immobilization pellets 1 to be filled in the wire net 14 is 3 mm, and 3 to 5 cm
In two cases, the nitrogen removal rate was determined after a fixed time from the start of the test when the dissolved oxygen concentration in the beaker 12 was changed. The test results will be described with reference to FIG. 5, which is a graph showing the relationship between the dissolved oxygen concentration and the nitrogen removal rate.
When the dissolved oxygen concentration is in the range of 0 to 1 mg / L, the nitrogen removal rates are both 100%, but the dissolved oxygen concentration is 1 m.
When g / L is exceeded, the nitrogen removal rate of the treated water 2 having the shortest diameter of the entrapping immobilization pellets 1 of 3 mm starts to significantly decrease, whereas the shortest diameter of the entrapping immobilization pellets 1 is 3 to 5 cm. Although the nitrogen removal rate of the treated water 2 begins to drop slightly,
Maintain nitrogen removal rate of over%. Considering the above results, the entrapping immobilization pellets 1 having a large shortest diameter of 3 to 5 cm show that oxygen contained in the nitrogen component in the water 2 to be treated is aerobic microorganisms in the outer portion 3 of the entrapping immobilization pellets 1. It is considered that the denitrification reaction could be caused by consuming it and forming an anaerobic part inside the carrier. The entrapping immobilization pellets 1 with a shortest diameter of 3 mm were capable of anaerobic denitrification under anaerobic conditions, that is, within a dissolved oxygen concentration range of 0 to 2 mg / L, but under aerobic conditions. It is considered that, since the dissolved oxygen concentration was high, oxygen could not be consumed in the inner part of the entrapping immobilization pellets 1 and the anaerobic part could not be formed. (Test Example 2) FIG. 6 is a graph showing the nitrogen removal rate after a fixed time after starting the test when the dissolved oxygen concentration is fixed at 7 mg / L and the shortest diameter of the entrapping immobilization pellets 1 is changed. Is. As shown in the same figure, the entrapping immobilization pellets 1 having the shortest diameter of the entrapping immobilization pellets 1 of less than 7.5 mm cannot form an anaerobic portion in the pellets and have a low nitrogen removal rate.
Further, it can be seen that the nitrogen removal rate is increased when the shortest diameter of the entrapping immobilization pellets 1 is 7.5 mm. This can be interpreted that the oxygen component is consumed in the outer portion 3 of the carrier, and the anaerobic portion is generated in the inner portion 4 of the carrier, where the denitrification reaction is performed. Next, when the shortest diameter of the entrapping immobilization pellets 1 is further increased, the nitrogen removal rate becomes maximum when the shortest diameter is about 4 cm, and thereafter, the nitrogen removal rate decreases as the shortest diameter increases. I understand. This is because if the shortest diameter is increased, it becomes difficult for the substance to be treated (nitrate nitrogen etc.) to permeate into the central portion 5 of the entrapping immobilization pellets 1, so that denitrification occurs even if an anaerobic portion is formed. It is thought that this is because a portion that cannot be used, that is, a portion that is not used in the reaction, is formed, and as a result, the nitrogen removal rate decreases.
【００１５】なお、本実施例では、包括固定化担体１の
みを浄化体６に充填し、浄化を行ったが、これに限ら
ず、包括固定化担体１以外の担体、例えばひも状担体、
スポンジ状担体、木炭、粒状担体など担体の表面に付
着、生成した微生物の作用を利用する担体と混在させて
用いてもよいのはもちろんである。In this embodiment, the purifying body 6 was filled with only the entrapping immobilization pellets 1 for purification. However, the present invention is not limited to this, and a carrier other than the entrapping immobilization pellets 1, for example, a string-shaped carrier,
Of course, it may be mixed with a carrier such as a sponge-like carrier, charcoal, or a granular carrier that adheres to the surface of the carrier and utilizes the action of the microorganisms produced.
【００１６】[0016]
【発明の効果】以上説明したように、本発明では、水質
浄化方法及びその装置に使用される包括固定化担体の大
きさを、好気条件下において、外側部分が好気条件にな
り、かつ、内側部分が嫌気条件となる大きさ、あるい
は、その最短径が７．５ｍｍ以上１００ｍｍ以下の大き
さとしたため、好気条件の被処理水を単一の包括固定化
担体を用いて硝化反応と脱窒反応との両反応を生じさせ
ることができ、好気条件の被処理水を効率良く浄化する
ことができる。また、被処理水の脱窒反応と硝化反応と
の両反応を単一の包括固定化担体で行わせることができ
るので、脱窒反応と硝化反応との両反応を行わせるため
に従来のような、脱気装置や曝気装置を用いる必要がな
く、設備コストを低く抑えることができる。As described above, according to the present invention, the size of the entrapping immobilization pellets used in the method for purifying water and the apparatus therefor is such that the outer portion is aerobic under aerobic conditions, and Since the inner part is anaerobic-sized or the shortest diameter is 7.5 mm or more and 100 mm or less, aerobically treated water is treated with nitrification reaction and denitrification using a single entrapping immobilization carrier. Both the nitrification reaction and the reaction can be caused, and the water to be treated under aerobic conditions can be efficiently purified. Further, since both the denitrification reaction and the nitrification reaction of the water to be treated can be carried out by a single entrapping immobilization carrier, the conventional method for carrying out both the denitrification reaction and the nitrification reaction is required. It is not necessary to use a deaeration device or an aeration device, and the equipment cost can be kept low.
【図１】 本発明の水質浄化装置の一実施形態に用いる
ことができる包括固定化担体を示す断面図である。FIG. 1 is a cross-sectional view showing an entrapping immobilization pellets that can be used in an embodiment of a water purification apparatus of the present invention.
【図２】 包括固定化担体の最短径の違いによる内部構
造の違いを模式的に示す図である。FIG. 2 is a diagram schematically showing a difference in internal structure due to a difference in the shortest diameter of the entrapping immobilization pellets.
【図３】 本発明の水質浄化装置の一実施形態を示す概
略構成図である。FIG. 3 is a schematic configuration diagram showing an embodiment of a water purification device of the present invention.
【図４】 試験装置を示す図である。FIG. 4 is a diagram showing a test apparatus.
【図５】 溶存酸素濃度と窒素除去率との関係を示すグ
ラフである。FIG. 5 is a graph showing the relationship between the dissolved oxygen concentration and the nitrogen removal rate.
【図６】 包括固定化担体の最短径を変化させた場合の
窒素除去率を示すグラフである。FIG. 6 is a graph showing a nitrogen removal rate when the shortest diameter of the entrapping immobilization pellets was changed.
１・・・包括固定化担体、２・・・被処理水、３・・・外側部
分、４・・・内側部分、７・・・浄化体、９・・・水質浄化装置1 ... entrapping immobilization carrier, 2 ... treated water, 3 ... outside part, 4 ... inside part, 7 ... purification body, 9 ... water purification device
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ テーマコート゛(参考） Ｃ１２Ｎ 11/08 Ｃ１２Ｎ 11/08 Ｄ (72)発明者 森 直道 東京都千代田区内神田一丁目１番14号 日 立プラント建設株式会社内 (72)発明者 浅井 史子 神奈川県川崎市川崎区富士見１丁目６番３ 号 トキコ株式会社内 (72)発明者 岩田 照史 神奈川県川崎市川崎区富士見１丁目６番３ 号 トキコ株式会社内 Ｆターム(参考） 4B029 AA02 AA21 BB02 CC05 DF04 4B033 NA02 NA12 NB34 NB37 NB66 NC06 ND04 NE07 NF06 4D003 AA01 AB11 BA06 DA01 EA01 EA17 EA19 EA30 4D040 BB02 BB07 BB42 BB52 BB82─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. 7 Identification code FI theme code (reference) C12N 11/08 C12N 11/08 D (72) Inventor Naomichi Mori 1-1-14 Uchikanda, Chiyoda-ku, Tokyo No. Hititsu Plant Construction Co., Ltd. (72) Inventor Fumiko Asai 1-3-6 Fujimi, Kawasaki-ku, Kawasaki-shi, Kanagawa Tokiko Co., Ltd. (72) Terumi Iwata 1-6 Fujimi, Kawasaki-ku, Kawasaki-shi, Kanagawa No. 3 Tokico F-term (reference) 4B029 AA02 AA21 BB02 CC05 DF04 4B033 NA02 NA12 NB34 NB37 NB66 NC06 ND04 NE07 NF06 4D003 AA01 AB11 BA06 DA01 EA01 EA17 EA19 EA30 4D040 BB02 BB07 BB42 BB42 BB42
Claims (4)
固定化担体により、好気条件の被処理水を浄化する水質
浄化方法であって、前記包括固定化担体は、前記好気条
件下において、外側部分が好気条件になり、かつ、内側
部分が嫌気条件となる大きさを有することを特徴とする
水質浄化方法。1. A water purification method for purifying water to be treated under aerobic conditions by using an entrapping immobilization carrier in which microorganisms are immobilized by an immobilizing agent, wherein the entrapping immobilization carrier is under the aerobic condition. A method for water purification, characterized in that the outer part has an aerobic condition and the inner part has an anaerobic condition.
固定化担体により、好気条件の被処理水を浄化する水質
浄化方法であって、前記包括固定化担体の最短径が７．
５ｍｍ以上１００ｍｍ以下の大きさであることを特徴と
する水質浄化方法。2. A water purification method for purifying water to be treated under aerobic conditions by using a comprehensive immobilization carrier in which microorganisms are immobilized with an immobilizing agent, wherein the entrapping immobilization carrier has a shortest diameter of 7.
A method for purifying water, which has a size of 5 mm or more and 100 mm or less.
固定化担体が収納された浄化体に好気条件の被処理水を
導入することにより当該被処理水を浄化する水質浄化装
置であって、前記包括固定化担体は、前記好気条件下に
おいて、外側部分が好気条件になり、かつ、内側部分が
嫌気条件となる大きさを有することを特徴とする水質浄
化装置。3. A water purification apparatus for purifying the water to be treated by introducing the water to be treated under aerobic conditions into a purification body containing a comprehensive immobilization carrier in which microorganisms are immobilized by an immobilizing agent. In the water purification device, the entrapping immobilization pellets have a size such that an outer part thereof is an aerobic condition and an inner part thereof is an anaerobic condition under the aerobic condition.
固定化担体が収納された浄化体に好気条件の被処理水を
導入することにより当該被処理水を浄化する水質浄化装
置であって、前記包括固定化担体の最短径が７．５ｍｍ
以上１００ｍｍ以下の大きさであることを特徴とする水
質浄化装置。4. A water purification apparatus for purifying the water to be treated by introducing the water to be treated under aerobic conditions into a purification body containing a comprehensive immobilization carrier in which microorganisms are immobilized by an immobilizing agent. , The shortest diameter of the entrapping immobilization pellets is 7.5 mm
A water purification apparatus having a size of 100 mm or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001191567A JP2003001284A (en) | 2001-06-25 | 2001-06-25 | Method for cleaning water and device therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001191567A JP2003001284A (en) | 2001-06-25 | 2001-06-25 | Method for cleaning water and device therefor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2003001284A true JP2003001284A (en) | 2003-01-07 |
Family
ID=19030171
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001191567A Pending JP2003001284A (en) | 2001-06-25 | 2001-06-25 | Method for cleaning water and device therefor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2003001284A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20070064280A (en) * | 2005-12-15 | 2007-06-20 | 가부시키가이샤 히타치플랜트테크놀로지 | Storage and manufacturing methods of encapsulated immobilization media |
| JP2009208024A (en) * | 2008-03-05 | 2009-09-17 | Nippon Kensetsu Gijutsu Kk | Water purification apparatus |
| JP2010179213A (en) * | 2009-02-04 | 2010-08-19 | Eco Earth Engineering Kk | Method and facility for purifying pollutant |
| JP2011212640A (en) * | 2010-04-02 | 2011-10-27 | Ihi Corp | Water clarifying method, water clarifying agent and method for producing water clarifying agent |
-
2001
- 2001-06-25 JP JP2001191567A patent/JP2003001284A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20070064280A (en) * | 2005-12-15 | 2007-06-20 | 가부시키가이샤 히타치플랜트테크놀로지 | Storage and manufacturing methods of encapsulated immobilization media |
| JP2009208024A (en) * | 2008-03-05 | 2009-09-17 | Nippon Kensetsu Gijutsu Kk | Water purification apparatus |
| JP2010179213A (en) * | 2009-02-04 | 2010-08-19 | Eco Earth Engineering Kk | Method and facility for purifying pollutant |
| JP2011212640A (en) * | 2010-04-02 | 2011-10-27 | Ihi Corp | Water clarifying method, water clarifying agent and method for producing water clarifying agent |
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