JPH0811236B2 - Operation management method of anaerobic treatment tank - Google Patents
Operation management method of anaerobic treatment tankInfo
- Publication number
- JPH0811236B2 JPH0811236B2 JP41156490A JP41156490A JPH0811236B2 JP H0811236 B2 JPH0811236 B2 JP H0811236B2 JP 41156490 A JP41156490 A JP 41156490A JP 41156490 A JP41156490 A JP 41156490A JP H0811236 B2 JPH0811236 B2 JP H0811236B2
- Authority
- JP
- Japan
- Prior art keywords
- dissolved oxygen
- anaerobic
- tank
- operation management
- treatment tank
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E50/00—Technologies for the production of fuel of non-fossil origin
- Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/10—Biological treatment of water, waste water, or sewage
Landscapes
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
- Treatment Of Sludge (AREA)
- Biological Treatment Of Waste Water (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は下水廃水等を絶対嫌気性
菌であるメタン菌を利用して分解処理させる嫌気性処理
槽の運転管理方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anaerobic treatment tank operation control method for decomposing sewage wastewater and the like using methane bacteria which are absolutely anaerobic bacteria.
【０００２】従来、メタン菌を利用して下水廃水等を嫌
気性処理する場合には、嫌気槽内における運転状況を管
理するために酸化還元電位計により測定されたＯＲＰ
（酸化還元電位）が使用されており、処理が良好に行わ
れているときにはＯＲＰが−400mV 以下を示すことを指
標として運転管理がなされていた。[0002] Conventionally, when sewage wastewater or the like is anaerobically treated by utilizing methane bacteria, ORP measured by an oxidation-reduction potentiometer in order to control the operating condition in the anaerobic tank.
(Oxidation-reduction potential) was used, and the operation was controlled with the ORP of -400 mV or less as an index when the treatment was performed well.
【０００３】ところがＯＲＰはメタン菌の活性に直接影
響する溶存酸素量のみならず、廃水中に混入している他
の還元因子等により大きく変動するため、嫌気槽の運転
状況を正確に測定することは不可能であった。このため
にＯＲＰは運転管理の指標としての信憑性が薄く、酸素
濃度が極めて低い領域で処理することが望まれる嫌気槽
の運転状況を正確に管理することはできなかった。However, since the ORP varies greatly not only with the amount of dissolved oxygen that directly affects the activity of methane bacteria but also with other reducing factors mixed in the wastewater, the operating conditions of the anaerobic tank must be accurately measured. Was impossible. For this reason, ORP has a low credibility as an index for operation management, and it has not been possible to accurately manage the operation status of the anaerobic tank, which is desired to be processed in a region where the oxygen concentration is extremely low.
【発明が解決しようとする課題】[Problems to be Solved by the Invention]
【０００４】本発明は上記した従来の問題点を解消し
て、従来取り上げられなかった廃水中に溶存している酸
素量のみに着目し、その許容される濃度を具体的に見出
すとともに、その酸素量を正確に測定することにより嫌
気槽の運転状況を正確に管理することができる嫌気性処
理方法を提供するために完成されたものである。The present invention solves the above-mentioned conventional problems, pays attention only to the amount of oxygen dissolved in waste water, which has not been taken up before, and specifically finds the allowable concentration.
In addition, the present invention has been completed to provide an anaerobic treatment method capable of accurately controlling the operating condition of an anaerobic tank by accurately measuring the amount of oxygen .
【０００５】上記の課題は、有機性廃水を嫌気性処理す
る際に、嫌気性処理槽内の溶存酸素濃度を溶存酸素計で
測定しつつ処理する嫌気性処理槽の運転管理方法におい
て、ガード電極で保護された弁座シール型の陰極をロッ
ドを介してスプリングにより弾発させることにより該陰
極と絶縁体との間隙からの酸素の侵入を防止した構造の
溶存酸素計で測定しつつ、かつ、該溶存酸素濃度のの最
大値を３０ｐｐｂに維持しながら処理することを特徴と
する嫌気性処理槽の運転管理方法によって解決すること
ができる。The above-mentioned problem is solved by measuring the dissolved oxygen concentration in the anaerobic treatment tank with a dissolved oxygen meter when the organic wastewater is anaerobically treated.
In the operation management method of the anaerobic treatment tank which treats while measuring
The valve seat seal type cathode protected by the guard electrode.
The spring is repelled by a spring
With a structure that prevents oxygen from entering through the gap between the pole and the insulator
While measuring with a dissolved oxygen meter,
Daine a can be solved by operation management method of anaerobic treatment tank, characterized in that the process while maintaining the 30pp b.
【０００６】以下に本発明を図示の実施例とともに更に
詳細に説明する。The present invention will be described in more detail below with reference to the embodiments shown in the drawings.
【０００７】[0007]
【実施例】図１は有機性廃水を嫌気性処理するための実
験装置を示すもので、１はメタン菌による発酵処理が行
われる嫌気槽、２は基質貯留槽、３は基質貯留槽２から
有機性廃水である基質を嫌気槽１へ投入するための投入
ポンプ、４は嫌気槽１内の液を攪拌する循環ポンプ、５
は処理水受槽、６は嫌気槽１内のメタン発酵により生じ
たメタンガスを貯留するガスホルダーである。嫌気槽１
内にはメタン菌を固定した固定床７が設けられており、
有機性廃水のメタン発酵を行わせている。EXAMPLE FIG. 1 shows an experimental apparatus for anaerobic treatment of organic wastewater, 1 is an anaerobic tank in which fermentation treatment with methane bacteria is performed, 2 is a substrate storage tank, 3 is a substrate storage tank 2 A charging pump for charging a substrate which is an organic wastewater into the anaerobic tank 1, a circulation pump 5 for stirring the liquid in the anaerobic tank 1,
Is a treated water receiving tank, and 6 is a gas holder for storing methane gas generated by methane fermentation in the anaerobic tank 1. Anaerobic tank 1
There is a fixed bed 7 in which methane bacteria are fixed,
Methane fermentation of organic wastewater is performed.
【０００８】このような嫌気槽１の底部には、酸素不透
過性のチューブ８を介して溶存酸素計９が接続されてい
る。この溶存酸素計９は槽内液が流されるチャンバー１
０と、電極部１１と、溶存酸素計本体１２とから構成さ
れるものである。A dissolved oxygen meter 9 is connected to the bottom of the anaerobic tank 1 through an oxygen impermeable tube 8. This dissolved oxygen meter 9 is a chamber 1 in which the liquid in the tank is made to flow.
0, the electrode part 11, and the dissolved oxygen meter main body 12 are comprised.
【０００９】実施例の溶存酸素計９は酸素分圧に感応す
るポーラログラフィック方式のもので、酸素分圧に対応
する酸素分子が半透膜を通じて陰極に達し、電気化学反
応を生じて電流が流れることを利用して酸素濃度を測定
する方式のものである。ところが通常の溶存酸素計では
酸素濃度が１ppm 以下になると電極部内の絶縁体から滲
み出す酸素等により測定誤差が指数関数的に増大し、絶
対嫌気性菌であるメタン菌に適した低濃度領域の酸素濃
度は測定できない。そこで実施例では図２に示される特
殊な構造の溶存酸素計９を使用することにしている。The dissolved oxygen meter 9 of the embodiment is a polarographic type which is sensitive to the oxygen partial pressure. Oxygen molecules corresponding to the oxygen partial pressure reach the cathode through the semipermeable membrane and cause an electrochemical reaction to generate an electric current. This is a method of measuring the oxygen concentration by utilizing the flow. However, in a normal dissolved oxygen meter, when the oxygen concentration is 1 ppm or less, the measurement error exponentially increases due to oxygen that oozes out from the insulator inside the electrode part, and the low concentration range suitable for methane bacteria which is an absolute anaerobic bacterium. Oxygen concentration cannot be measured. Therefore, in the embodiment it is to use the dissolved oxygen meter 9 special structure shown in FIG.
【００１０】図２の溶存酸素計９において、１３は厚さ
が２μ程度の半透膜、１４は純金製の陰極、１５は純銀
製の陽極である。この溶存酸素計９では陰極１４の周囲
に銀製のガード電極１６が設けてあり、このガード電極
１６は陰極１４と同電位に保たれているので外部から侵
入する酸素分子が陰極１４に到達する前にガード電極１
６により除去される。また１７はサファイア製の絶縁体
であるが、その裏側から陰極１４との微細な隙間を通じ
て酸素分子が侵入する可能性がある。そこでこの溶存酸
素計９では陰極１４の形状を弁座シール型とし、陰極１
４をロッド１８を介してスプリング１９により下方へ弾
発させることにより、陰極１４と絶縁体１７との間隙か
らの酸素分子の侵入を防止している。このような構造の
溶存酸素計９を使用すれば、電極内に存在する微量の酸
素による誤差をなくし、嫌気槽１の槽内液の酸素濃度を
１ppb まで正確に測定することが可能となる。In the dissolved oxygen meter 9 of FIG. 2, 13 is a semipermeable membrane having a thickness of about 2 μ, 14 is a cathode made of pure gold, and 15 is an anode made of pure silver. In this dissolved oxygen meter 9, a silver guard electrode 16 is provided around the cathode 14, and since this guard electrode 16 is kept at the same potential as the cathode 14, before oxygen molecules invading from the outside reach the cathode 14. On the guard electrode 1
Removed by 6. Further, 17 is an insulator made of sapphire, but oxygen molecules may enter from the back side through a minute gap with the cathode 14. Therefore, in this dissolved oxygen meter 9, the shape of the cathode 14 is a valve seat seal type, and the cathode 1
4 is elastically urged downward by a spring 19 via a rod 18, so that oxygen molecules are prevented from entering through the gap between the cathode 14 and the insulator 17. By using the dissolved oxygen meter 9 having such a structure, it is possible to eliminate an error due to a slight amount of oxygen existing in the electrode and to accurately measure the oxygen concentration of the liquid in the anaerobic tank 1 to 1 ppb.
【００１１】本発明では、上記したような構造のポーラ
ログラフィック方式の溶存酸素計９を使用し、嫌気槽１
の槽内液の酸素濃度を定期的に測定する。そして槽内の
溶存酸素濃度の最大値を30ppb に維持することを指標と
して運転管理を行う。In the present invention, using a dissolved oxygen meter 9 of polarographic method structure as noted above, the anaerobic tank 1
Oxygen concentration of the liquid in the tank is measured regularly. Then, operation management will be performed with the index of maintaining the maximum dissolved oxygen concentration in the tank at 30 pp b .
【００１２】ここで指標となる溶存酸素濃度の最大値を
30ppb としたのは、次に示す通り溶存酸素濃度がこれを
超過するとメタン菌の処理能力が低下するためである。Here, the maximum value of the dissolved oxygen concentration which is an index is
Was a 30Pp b, as dissolved oxygen concentration shown below is this
It exceeds the processing capacity of the methane bacteria in order to decrease.
【００１３】すなわち、図３は図１の実験装置を利用し
て嫌気槽１の槽内液の酸素濃度を変化させつつ揮発性有
機酸（ＶＦＡ）の発生量を測定した結果を示すものであ
る。測定は同一条件で２４時間の運転後に行った。図３
のグラフから明らかなように、嫌気槽１の槽内液の溶存
酸素濃度が30ppb を越えると揮発性有機酸の発生量が顕
著に増加し、一応の目処とされる５００mg/lを越えるよ
うになる。That is, FIG. 3 shows the results of measuring the amount of volatile organic acid (VFA) generated while changing the oxygen concentration of the liquid in the anaerobic tank 1 using the experimental apparatus of FIG. . The measurement was performed under the same conditions after 24 hours of operation. FIG.
As is clear from the graph, when the dissolved oxygen concentration of the liquid in the anaerobic tank 1 exceeds 30 ppb, the amount of volatile organic acids generated remarkably increases, so that the volatile organic acid exceeds 500 mg / l. Become.
【００１４】また図４は同様に嫌気槽１の槽内液の酸素
濃度を変化させつつ発生ガス中のメタン含量を測定した
結果を示すものである。図４のグラフから明らかなよう
に、嫌気槽１の槽内液の溶存酸素濃度が30ppb を越える
と発生ガス中のメタン含量は低下し、一応の目処とされ
る６０％を下回るようになる。Similarly, FIG. 4 shows the results of measuring the methane content in the evolved gas while changing the oxygen concentration of the liquid in the anaerobic tank 1. As is clear from the graph of FIG. 4, when the dissolved oxygen concentration of the liquid in the tank of the anaerobic tank 1 exceeds 30 ppb, the methane content in the generated gas decreases, and falls below 60%, which is a tentative target.
【００１５】このような減少が起こる原因としては、溶
存酸素濃度が30ppb を越えるとメタン菌の活性が低下
し、槽内に共存している通性嫌気性菌の酸生成菌が優勢
となり、次第に有機酸が蓄積されていくことが考えられ
る。また酸生成反応によって生ずる炭酸ガスの増加に伴
い、発生ガス中のメタン含量は低下することとなる。The cause of such a decrease is that when the dissolved oxygen concentration exceeds 30 ppb, the activity of methane bacteria decreases, and acid-producing bacteria of facultative anaerobic bacteria coexisting in the tank become dominant, and gradually. It is possible that organic acids accumulate. Further, as the carbon dioxide gas generated by the acid generation reaction increases, the methane content in the generated gas decreases.
【００１６】このように、槽内の溶存酸素濃度の最大値
を30ppb に維持することを指標として運転管理を行え
ば、常にメタン菌の活性をハイレベルに維持したままで
嫌気性処理を進行させることができる。[0016] Anaerobic Thus, while maintaining by performing the operation management as an index to keep the maximum value <br/> dissolved oxygen concentration in the bath to 30Pp b, always the activity of methane bacteria in a high level Sexual processing can proceed.
【００１７】[0017]
【発明の効果】以上に説明したように、本発明によれば
従来は管理指標とされることのなかった槽内の溶存酸素
濃度をｐｐｂ単位まで精度よく測定することができると
ともに、その最大値を３０ｐｐｂに維持することを指標
として運転管理を行うので、メタン菌の活性を直接把握
することができ、メタン菌の活性をハイレベルに維持し
て効率良く嫌気性処理を行うことができる。なお、溶存
酸素濃度が３０ｐｐｂを越えたときには酸素混入の原因
を直ちに調査して取り除くことができ、メタン菌の失活
等のトラブルを未然に防止することができるようにな
る。よって本発明は従来の問題点を解決した嫌気性処理
槽の運転管理方法として、産業の発展に寄与するところ
は極めて大きいものである。As described above, according to the present invention, conventional according to the present invention to be able to measure accurately the concentration of dissolved oxygen which was not in the tank it is are managed index up ppb units
Because both perform the operation management as an index to keep the maximum value 30Pp b, it is possible to directly understand the activity of methane bacteria, efficiently anaerobic treatment to maintain the activity of methane bacteria in a high level It can be carried out. When the dissolved oxygen concentration exceeds 30 ppb, the cause of oxygen contamination can be immediately investigated and removed, and troubles such as deactivation of methane bacteria can be prevented. Therefore, the present invention, as an operation management method for an anaerobic treatment tank that solves the conventional problems, has a great contribution to the industrial development.
【００１８】[0018]
【図１】本発明の実施例に用いた嫌気性処理装置の配管
系統図である。FIG. 1 is a piping system diagram of an anaerobic treatment apparatus used in an example of the present invention.
【図２】本発明の実施例に用いた溶存酸素計の電極部の
断面図である。FIG. 2 is a sectional view of an electrode portion of a dissolved oxygen meter used in an example of the present invention.
【図３】溶存酸素濃度と揮発性有機酸の発生量との関係
を示すグラフである。FIG. 3 is a graph showing the relationship between the dissolved oxygen concentration and the amount of volatile organic acids generated.
【図４】溶存酸素濃度と発生ガス中のメタン含量との関
係を示すグラフである。FIG. 4 is a graph showing the relationship between the dissolved oxygen concentration and the methane content in the generated gas.
１ 嫌気槽 ９ 溶存酸素計 １４ 陰極 １６ ガード電極 1 Anaerobic tank 9 Dissolved oxygen meter 14 Cathode 16 Guard electrode
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｇ０１Ｎ 27/404 (72)発明者 山崎 仁敬 愛知県名古屋市瑞穂区岳見町１丁目34番地 日本ガイシ岳見寮108号 (56)参考文献 特開 昭52−117195（ＪＰ，Ａ) 特開 昭59−3345（ＪＰ，Ａ) 高原義昌編著、廃水の生物処理、昭和55 −４−30発行、（株）地球社、第167〜182 頁（特に図６−６参照)─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 6 Identification number Internal reference number FI Technical indication location G01N 27/404 (72) Inventor Hitoshi Yamazaki 1-34 Takemi-cho, Mizuho-ku, Nagoya, Aichi Japan Gaishi Takemi Dormitory No. 108 (56) Reference JP-A-52-117195 (JP, A) JP-A-59-3345 (JP, A) edited by Yoshimasa Takahara, biological treatment of wastewater, published 55-4-30, Earth Co., Ltd., pp. 167-182 (see especially Fig. 6-6)
Claims (1)
性処理槽内の溶存酸素濃度を溶存酸素計で測定しつつ処
理する嫌気性処理槽の運転管理方法において、ガード電
極で保護された弁座シール型の陰極をロッドを介してス
プリングにより弾発させることにより該陰極と絶縁体と
の間隙からの酸素の侵入を防止した構造の溶存酸素計で
測定しつつ、かつ、該溶存酸素濃度のの最大値を３０ｐ
ｐｂに維持しながら処理することを特徴とする嫌気性処
理槽の運転管理方法。The method according to claim 1 the organic wastewater in processing anaerobic, anaerobic
The dissolved oxygen concentration in the oxidative treatment tank is measured with a dissolved oxygen meter.
In the operation management method of the anaerobic treatment tank,
A valve-seal type cathode protected by a pole is swung through a rod.
By pulling the cathode and the insulator
With a dissolved oxygen meter with a structure that prevents the intrusion of oxygen from the gap of
While measuring, the maximum value of the dissolved oxygen concentration is 30p
operation management method of the anaerobic treatment tank, characterized in that the process while maintaining the p b.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP41156490A JPH0811236B2 (en) | 1990-12-17 | 1990-12-17 | Operation management method of anaerobic treatment tank |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP41156490A JPH0811236B2 (en) | 1990-12-17 | 1990-12-17 | Operation management method of anaerobic treatment tank |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04215897A JPH04215897A (en) | 1992-08-06 |
| JPH0811236B2 true JPH0811236B2 (en) | 1996-02-07 |
Family
ID=18520549
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP41156490A Expired - Lifetime JPH0811236B2 (en) | 1990-12-17 | 1990-12-17 | Operation management method of anaerobic treatment tank |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0811236B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6336757B2 (en) * | 2012-11-29 | 2018-06-06 | 株式会社 堀場アドバンスドテクノ | measuring device |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH619047A5 (en) * | 1976-03-12 | 1980-08-29 | Orbisphere Corp | |
| JPS593345A (en) * | 1982-06-30 | 1984-01-10 | Hitachi Ltd | Dissolved oxygen meter equipped with electrode for removing interfering component |
-
1990
- 1990-12-17 JP JP41156490A patent/JPH0811236B2/en not_active Expired - Lifetime
Non-Patent Citations (1)
| Title |
|---|
| 高原義昌編著、廃水の生物処理、昭和５５−４−３０発行、（株）地球社、第１６７〜１８２頁（特に図６−６参照） |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04215897A (en) | 1992-08-06 |
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