JP2004321959A - Waste liquid treatment apparatus - Google Patents

Waste liquid treatment apparatus Download PDF

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Publication number
JP2004321959A
JP2004321959A JP2003121082A JP2003121082A JP2004321959A JP 2004321959 A JP2004321959 A JP 2004321959A JP 2003121082 A JP2003121082 A JP 2003121082A JP 2003121082 A JP2003121082 A JP 2003121082A JP 2004321959 A JP2004321959 A JP 2004321959A
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JP
Japan
Prior art keywords
waste liquid
ozone gas
ozone
organic matter
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.)
Pending
Application number
JP2003121082A
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Japanese (ja)
Inventor
Hiroyuki Tsuchiya
弘行 土屋
Misoji Ebine
三十治 海老根
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Engineering Co Ltd
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Hitachi Engineering Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hitachi Engineering Co Ltd filed Critical Hitachi Engineering Co Ltd
Priority to JP2003121082A priority Critical patent/JP2004321959A/en
Publication of JP2004321959A publication Critical patent/JP2004321959A/en
Pending legal-status Critical Current

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Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus which efficiently carries out the oxidative degradation of organic substances contained in a waste liquid discharged from general households, food manufacturing industry, and the like. <P>SOLUTION: Ozone gas generated by an ozonizer 4 and the waste liquid drawn from the bottom of a treatment tank 3 are fed to a microbubble generator 1 through a pressurization pump 5. The generated ozone microbubbles are fed into the waste liquid in the treatment tank 3 from the openings of a gas blowout pipe 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【0001】
【発明の属する技術分野】
本発明は、一般家庭、食品製造業等から排出される廃液の処理装置係り、特に廃液中に含まれる有機物を分解処理する廃液の処理装置に関する。
【0002】
【従来の技術】
【特許文献1】特開平6−304581号公報
一般家庭、食品製造業等から排出される廃液中には有機物が含まれている。この廃液を放流するには廃液中の有機物を分解処理する必要がある。有機物を含有する廃液を処理する方法として、有機物含有廃液にオゾンガスを吹き込むことが知られている。廃液中にオゾンガスを吹き込み溶解させ、有機物が溶解したオゾンと化学反応して酸化分解される。
【0003】
廃液中に吹きこむオゾンガスは気泡の大きさがミリメートル以上のものが用いられている。ミリメートル以上の径を有する気泡(ミリバブルと呼称する)は廃液中での上昇速度が大きくなる。オゾンガスは上昇速度が大きいと廃液中に十分溶け込む前に液面に到達して消滅する。
【0004】
【発明が解決しようとする課題】
従来技術はミリバブルのオゾンガスを吹き込んで廃液中に溶解させているが、十分溶け込む前に液面に到達して消滅するために酸化分解効率が低いという問題点を有する。
【0005】
本発明の目的は一般家庭、食品製造業等から排出される有機物含有廃液に含まれる有機物を効率良く酸化分解することができる廃液の処理装置を提供することにある。
【0006】
【課題を解決するための手段】
本発明の特徴とするところは、オゾンガスと処理槽から加圧ポンプによって圧送される有機物含有廃液を混合してオゾンガスの気泡径を微細化してマイクロバブルとし、マイクロバブル化されたオゾンガスを処理槽の下部に供給するようにしたことにある。
【0007】
換言すると、本発明はオゾンガスと加圧ポンプで圧送される有機物含有廃液とを高遠心力場において混合することにより、オゾンガスの気泡径を微細化して処理槽の下部に供給するようにしたものである。
【0008】
本発明はオゾンガスの気泡径を微細化しているので上昇速度が小さくなり廃液中に十分溶解でき有機物含有廃液に含まれる有機物を効率良く酸化分解することができる。
【0009】
【発明の実施の形態】
図1に本発明の一実施例を示す。
【0010】
図1において、有機物を含む廃液は有機物含有廃液にオゾンガスを溶解させ有機物を酸化分解処理する処理槽3に貯められる。オゾン発生装置4には空気または酸素ガスが供給される。オゾン発生装置4は高電界放電場において空気または酸素からオゾンガスを生成しマイクロバブル発生装置1に供給する。
【0011】
処理槽3の下部には移送ライン10が設けられ加圧ポンプ5に接続されている。廃液は加圧ポンプ5から移送ライン11を介してマイクロバブル発生装置1に圧送される。加圧ポンプ5により圧送された廃液はマイクロバブル発生装置1の内部で回転しオゾンガスを吸い込むようになる。
【0012】
マイクロバブル発生装置1の内部は廃液の回転により高遠心力になっているため、オゾンガスは廃液と高遠心力場で混合され微細な径を有するいわゆるマイクロバブル化される。
【0013】
マイクロバブルは「その発生時において、気泡径が10〜40μm程度のごく微細な気泡」と定義されている。このことは、例えば、刊行物「水工学論文集」(土木学会発行、第46号、第1163〜1168頁、2002年2月発行)。
【0014】
マイクロバブル発生装置1により生成されたオゾンガスマイクロバブルは移送ライン12を介し、処理槽3の下部に設置されているガス吹き出しパイプ2の開口部から廃液中に通気される。ガス吹き出しパイプ2の開口部より処理液中に通気されたオゾンガスマイクロバブルは気泡径が10〜40μm程度と小さいため、廃液中での上昇速度が非常に小さく、上昇過程で消失し、廃液中に溶解する。すなわち、オゾンガスの廃液中への溶解性が高くなる。
【0015】
溶解したオゾンは廃液中の有機物と化学反応し、有機物は酸化分解される。処理槽3内の廃液は攪拌装置6により攪拌され、槽内の廃液は均一な状態に保たれる。廃液中の有機物の濃度は処理槽3に接続された総有機炭素(Total Organic Carbon、TOC)メータ7により測定される。
このように処理された廃液は移送ライン8より次工程へ移送される。同時に移送ライン9から新しい処理液が投入される。
【0016】
このように廃液の有機物を処理するのであるが、本発明の効果を具体的に試験結果に基づいて説明する。
【0017】
有機物濃度60ppmの廃液100lを供試試料とし、空気1l/minをオゾン発生装置4に供給し、生成したオゾンガスをマイクロバブル発生装置1に供給する。また、廃液30l/minをマイクロバブル発生装置1に圧送し、生成したオゾンマイクロバブルを廃液に連続的に通気し、2時間後の有機物濃度を測定した結果、3ppmと大幅に低減することができた。
【0018】
比較例として、空気1l/minをオゾン発生装置4に供給し、マイクロバブル発生装置1を経由せずに廃液中に通気したところ、2時間後の有機物濃度は10ppmであった。これらの試験結果により、本発明の効果は明らかであることが判る。
【0019】
このように廃液の有機物を処理するのであるが、オゾンガスの気泡径を微細化しているので上昇速度が小さくなり廃液中に十分溶解でき有機物含有廃液に含まれる有機物を効率良く酸化分解することができる。
【0020】
【発明の効果】
本発明はオゾンガスの気泡径を微細化しているので上昇速度が小さくなり廃液中に十分溶解でき有機物含有廃液に含まれる有機物を効率良く酸化分解することができる。
【図面の簡単な説明】
【図1】本発明の一実施例を示す構成図である。
【符号の説明】
1…マイクロバブル発生装置、2…ガス吹き出しパイプ、3…処理槽、4…オゾン発生装置、5…加圧ポンプ、6…攪拌装置、7…TOCメータ、8〜12…移送ライン。
[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for treating waste liquid discharged from general households, the food manufacturing industry, and the like, and more particularly to an apparatus for treating waste liquid that decomposes organic substances contained in the waste liquid.
[0002]
[Prior art]
[Patent Document 1] Japanese Patent Application Laid-Open No. 6-304581 The waste liquid discharged from ordinary households, the food manufacturing industry, and the like contains organic substances. In order to discharge this waste liquid, it is necessary to decompose organic substances in the waste liquid. As a method of treating a waste liquid containing an organic substance, it is known to blow ozone gas into the waste liquid containing an organic substance. Ozone gas is blown into the waste liquid to dissolve it, and the organic matter chemically reacts with the dissolved ozone to be oxidatively decomposed.
[0003]
The ozone gas blown into the waste liquid has a bubble size of millimeters or more. Bubbles having a diameter of millimeters or more (referred to as millibubbles) have a high rise speed in the waste liquid. If the rising speed of the ozone gas is high, the ozone gas reaches the liquid level before being sufficiently dissolved in the waste liquid and disappears.
[0004]
[Problems to be solved by the invention]
In the prior art, ozone gas of millibubbles is blown into the waste liquid to dissolve it, but it has a problem that the oxidative decomposition efficiency is low because the ozone gas reaches the liquid surface before being sufficiently dissolved and disappears.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to provide a waste liquid treatment apparatus capable of efficiently oxidatively decomposing organic substances contained in organic substance-containing waste liquid discharged from households, food manufacturers, and the like.
[0006]
[Means for Solving the Problems]
The feature of the present invention is that the ozone gas and the organic matter-containing waste liquid pumped from the treatment tank by a pressure pump are mixed to make the bubble diameter of the ozone gas fine to form microbubbles. That is to supply to the lower part.
[0007]
In other words, in the present invention, the ozone gas and the organic matter-containing waste liquid pumped by the pressure pump are mixed in a high centrifugal force field, so that the bubble diameter of the ozone gas is reduced and supplied to the lower part of the processing tank. .
[0008]
In the present invention, since the bubble diameter of the ozone gas is made finer, the rising speed is reduced and the ozone gas can be sufficiently dissolved in the waste liquid to efficiently oxidatively decompose the organic matter contained in the organic matter-containing waste liquid.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows an embodiment of the present invention.
[0010]
In FIG. 1, a waste liquid containing an organic substance is stored in a treatment tank 3 for dissolving ozone gas in the organic substance-containing waste liquid and oxidatively decomposing the organic substance. Air or oxygen gas is supplied to the ozone generator 4. The ozone generator 4 generates ozone gas from air or oxygen in a high electric field discharge field and supplies it to the microbubble generator 1.
[0011]
A transfer line 10 is provided below the processing tank 3 and is connected to the pressure pump 5. The waste liquid is sent to the microbubble generator 1 from the pressure pump 5 via the transfer line 11 under pressure. The waste liquid pumped by the pressure pump 5 rotates inside the microbubble generator 1 and sucks ozone gas.
[0012]
Since the inside of the microbubble generator 1 has a high centrifugal force due to the rotation of the waste liquid, the ozone gas is mixed with the waste liquid in a high centrifugal force field to form so-called microbubbles having a fine diameter.
[0013]
Microbubbles are defined as "very fine bubbles having a bubble diameter of about 10 to 40 [mu] m at the time of their generation". This is described, for example, in the publication “Hydraulic Engineering Transactions” (published by Japan Society of Civil Engineers, No. 46, pp. 1163-1168, published in February 2002).
[0014]
The ozone gas microbubbles generated by the microbubble generator 1 are passed through the transfer line 12 from the opening of the gas blowing pipe 2 installed at the lower part of the processing tank 3 into the waste liquid. Since the ozone gas microbubbles ventilated into the processing liquid from the opening of the gas blowing pipe 2 have a small bubble diameter of about 10 to 40 μm, the rising speed in the waste liquid is very small, and the ozone gas microbubbles disappear in the ascending process. Dissolve. That is, the solubility of the ozone gas in the waste liquid is increased.
[0015]
The dissolved ozone chemically reacts with the organic matter in the waste liquid, and the organic matter is oxidized and decomposed. The waste liquid in the processing tank 3 is stirred by the stirring device 6, and the waste liquid in the tank is kept in a uniform state. The concentration of the organic matter in the waste liquid is measured by a total organic carbon (TOC) meter 7 connected to the treatment tank 3.
The waste liquid thus treated is transferred from the transfer line 8 to the next step. At the same time, a new processing liquid is supplied from the transfer line 9.
[0016]
In this way, the organic matter in the waste liquid is treated. The effect of the present invention will be specifically described based on test results.
[0017]
100 l of waste liquid having an organic substance concentration of 60 ppm is used as a test sample, 1 l / min of air is supplied to the ozone generator 4, and the generated ozone gas is supplied to the microbubble generator 1. In addition, 30 l / min of waste liquid was sent to the microbubble generator 1 under pressure, and the generated ozone microbubbles were continuously ventilated to the waste liquid. The organic matter concentration after 2 hours was measured. Was.
[0018]
As a comparative example, air at 1 l / min was supplied to the ozone generator 4 and aerated in the waste liquid without passing through the microbubble generator 1, and the organic matter concentration after 2 hours was 10 ppm. These test results show that the effect of the present invention is clear.
[0019]
In this way, the organic matter in the waste liquid is treated. However, since the bubble diameter of the ozone gas is made finer, the rising speed is reduced, the organic matter contained in the organic matter-containing waste liquid can be efficiently dissolved by being sufficiently dissolved in the waste liquid, and oxidatively decomposed. .
[0020]
【The invention's effect】
In the present invention, since the bubble diameter of the ozone gas is made finer, the rising speed is reduced and the ozone gas can be sufficiently dissolved in the waste liquid to efficiently oxidatively decompose the organic matter contained in the organic matter-containing waste liquid.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing one embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Microbubble generator, 2 ... Gas blowing pipe, 3 ... Processing tank, 4 ... Ozone generator, 5 ... Pressurizing pump, 6 ... Stirrer, 7 ... TOC meter, 8-12 ... Transfer line.

Claims (1)

有機物含有廃液にオゾンガスを溶解させ有機物を酸化分解処理する処理槽と、オゾンガスを発生するオゾン発生装置と、前記オゾンガスと前記処理槽から加圧ポンプによって圧送される前記有機物含有廃液を混合して前記オゾンガスの気泡径を微細化するマイクロバブル発生装置と、前記マイクロバブル発生装置で微細化されたオゾンガスを前記処理槽の下部に供給するオゾン供給手段と、前記処理槽内の有機物含有廃液を攪拌する攪拌装置とを具備することを特徴とする廃液の処理装置。A treatment tank for dissolving ozone gas in an organic matter-containing waste liquid to oxidatively decompose organic matter, an ozone generator for generating ozone gas, and mixing the ozone gas and the organic matter-containing waste liquid pressure-fed from the treatment tank by a pressure pump; A microbubble generator for reducing the bubble diameter of the ozone gas, an ozone supply means for supplying the ozone gas refined by the microbubble generator to a lower portion of the processing tank, and stirring the organic-containing waste liquid in the processing tank. An apparatus for treating waste liquid, comprising: a stirring device.
JP2003121082A 2003-04-25 2003-04-25 Waste liquid treatment apparatus Pending JP2004321959A (en)

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