JP2539555B2 - Water ozonation method - Google Patents
Water ozonation methodInfo
- Publication number
- JP2539555B2 JP2539555B2 JP3204930A JP20493091A JP2539555B2 JP 2539555 B2 JP2539555 B2 JP 2539555B2 JP 3204930 A JP3204930 A JP 3204930A JP 20493091 A JP20493091 A JP 20493091A JP 2539555 B2 JP2539555 B2 JP 2539555B2
- Authority
- JP
- Japan
- Prior art keywords
- ozone
- tank
- water
- treatment
- containing air
- 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 - Fee Related
Links
Description
【０００１】[0001]
【産業上の利用分野】本発明は、上水、下水、産業排水
等の水中に含まれる有機物、臭気度、色度等を除去する
ための水のオゾン処理法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for ozone treatment of water for removing organic substances, odor and chromaticity contained in water such as tap water, sewage and industrial waste water.
【０００２】[0002]
【従来の技術】従来の水のオゾン処理法としては、図８
及び図９に示されるように処理槽１の底部からオゾン発
生機２により発生させたオゾン含有空気を吹き込み、処
理槽１の上部から供給した原水を槽内でオゾンと接触さ
せて水中の有機物等を除去させる方法が知られている。
ところが一般にブロア４はオゾンによる腐食を避けるた
めにオゾンと接触させることができず、オゾン発生機２
の前段に設置する必要がある。このために図８、図９と
もにブロア４の圧力によりオゾン含有空気を処理槽１内
に圧送する方法を取っており、散気水深が大きくなると
オゾン発生機２内の圧力が高くなってオゾン発生量が減
少し、一定量のオゾンを得るのに多大な電力を必要とす
る欠点があった。2. Description of the Related Art The conventional ozone treatment method for water is shown in FIG.
As shown in FIG. 9, the ozone-containing air generated by the ozone generator 2 is blown from the bottom of the treatment tank 1, and the raw water supplied from the upper portion of the treatment tank 1 is brought into contact with ozone in the tank so that organic matter in water, etc. There is known a method of removing the.
However, in general, the blower 4 cannot be brought into contact with ozone in order to avoid corrosion by ozone, and the ozone generator 2
It is necessary to install it in front of. Therefore, in both FIGS. 8 and 9, the ozone-containing air is pressure-fed into the processing tank 1 by the pressure of the blower 4, and when the diffused water depth becomes large, the pressure in the ozone generator 2 becomes high and ozone is generated. There is a drawback that the amount is reduced and a large amount of electric power is required to obtain a certain amount of ozone.
【０００３】[0003]
【発明が解決しようとする課題】本発明は上記した従来
の問題点を解消し、オゾン製造コストを低く押さえるこ
とができ、しかも優れた処理水質を達成することができ
る水のオゾン処理法を提供するために完成されたもので
ある。DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, provides an ozone treatment method for water which can keep ozone production costs low and can achieve excellent treated water quality. It was completed in order to do.
【０００４】[0004]
【課題を解決するための手段】上記の課題は、処理槽底
部よりオゾン発生機から得られるオゾン含有空気を送気
しつつ処理槽上部より原水を供給して有機物や臭気等の
分解を行わせる水のオゾン処理法において、槽底部より
引き出された処理水の一部をオゾン含有空気と混合した
後、気液混合ポンプによって処理槽底部の散気管に圧送
してオゾン発生機の内圧を常圧に保ちつつ、該オゾン含
有空気を処理槽内に散気すると同時に該混合処理水を該
散気管より処理槽に返送することを特徴とする水のオゾ
ン処理法によって解決することができる。[Means for Solving the Problems] The above problems are caused by supplying ozone-containing air obtained from an ozone generator from the bottom of the treatment tank while supplying raw water from the upper portion of the treatment tank to decompose organic substances and odors. in the ozone treatment of water, it was mixed with a portion of the treated water drawn from the tank bottom and the ozone-containing air
After that , it is pumped to the diffuser pipe at the bottom of the processing tank by a gas-liquid mixing pump.
While maintaining the internal pressure of the ozone generator at normal pressure,
Aerated air is diffused into the treatment tank and at the same time the mixed treated water is
This can be solved by an ozone treatment method of water, which is characterized in that the water is returned from the air diffuser to the treatment tank.
【０００５】[0005]
【実施例】以下に本発明を図面を参照しつつ更に詳細に
説明する。第１の実施例を示す図１において、１は処理
槽、２はオゾン発生機、３は気液混合ポンプである。本
発明においては、処理槽１の槽底部に設けられた排水管
５によって槽底部より引き出された処理水の一部を循環
水として気液混合ポンプ３の吸引側に循環させ、オゾン
発生機２により製造されたオゾン含有空気と混合攪拌し
たうえで散気管６を通じて再び処理槽の底部へ戻すのと
同時にオゾン含有空気を散気管６を通じて処理槽内に散
気している。これはオゾン発生機２の前段に設置された
ブロアの圧力によりオゾン含有空気を槽内に圧入してい
た従来法と大きく異なる点である。The present invention will be described in more detail below with reference to the drawings. In FIG. 1 showing the first embodiment, 1 is a processing tank, 2 is an ozone generator, and 3 is a gas-liquid mixing pump. In the present invention, a part of the treated water drawn out from the bottom of the tank by the drainage pipe 5 provided at the bottom of the tank 1 is circulated as circulating water to the suction side of the gas-liquid mixing pump 3 to generate the ozone generator 2 and the to return again to the bottom of the processing tank through the pipe 6 diffusing upon stirring mixture, manufactured with ozone-containing air by
At the same time, ozone-containing air is diffused into the treatment tank through the diffuser pipe 6.
I care . This is a significant difference from the conventional method in which ozone-containing air is pressed into the tank by the pressure of the blower installed in the previous stage of the ozone generator 2.
【０００６】通常、オゾン処理槽の散気水深は４ｍ程度
あり、配管抵抗を加えてオゾン含有空気を処理槽１内に
散気するには0.5kg/cm2 程度の圧力が必要となる。い
ま、オゾン含有空気を処理槽１内に圧入しつつオゾン含
有空気を製造しているオゾン発生機２内の空気圧力を見
ると、図８、図９の従来法ではオゾン含有空気の散気に
必要な圧力0.5kg/cm2 を加えて絶対圧で1.5kg/cm2 が必
要であるのに対して、本発明ではオゾン含有空気の散気
に必要な圧力は気液混合ポンプ３によってまかなわれる
ので絶対圧で1.0kg/cm2 （常圧）のみでよい。オゾン発
生機２には、 オゾン発生開始電圧＝空気絶対圧×電極間距離 の関係があるので、オゾン発生機２内の空気圧力を低く
押さえることは同じオゾン量を得るのに必要な電力量が
少なくて済む効果がある。Normally, the depth of diffused water in the ozone treatment tank is about 4 m, and a pressure of about 0.5 kg / cm 2 is required to diffuse ozone-containing air into the treatment tank 1 by adding pipe resistance. Now, looking at the air pressure in the ozone generator 2 that is producing ozone-containing air while pressurizing the ozone-containing air into the treatment tank 1, the conventional method shown in FIGS. In contrast to the required pressure of 0.5 kg / cm 2 and the absolute pressure of 1.5 kg / cm 2 , in the present invention, the pressure required to diffuse ozone-containing air is provided by the gas-liquid mixing pump 3. Therefore, only 1.0 kg / cm 2 (normal pressure) is required in absolute pressure. Since the ozone generator 2 has a relationship of ozone generation start voltage = absolute air pressure × distance between electrodes, keeping the air pressure in the ozone generator 2 low requires a sufficient amount of electric power to obtain the same ozone amount. It has the effect of being small.
【０００７】この効果は、従来ではオゾン発生機２の前
段に設置されたブロアの圧力によって賄われていた処理
槽１へのオゾン含有空気の散気圧力を新たにオゾン発生
機２の後段に設置した気液混合ポンプ３の圧力で賄い、
オゾン発生機２内の圧力を常圧に保つことによって達成
されるものである。この気液混合ポンプ３は、循環水と
オゾン含有空気の混合物を処理槽１に送る特性上、気液
混合物を移送できることが必要である。This effect is achieved by newly installing the diffused pressure of the ozone-containing air to the processing tank 1 in the subsequent stage of the ozone generator 2 which was conventionally covered by the pressure of the blower installed in the previous stage of the ozone generator 2. It is covered by the pressure of the gas-liquid mixing pump 3
This is achieved by maintaining the pressure inside the ozone generator 2 at normal pressure. This gas-liquid mixing pump 3 needs to be able to transfer the gas-liquid mixture because of the characteristic of sending a mixture of circulating water and ozone-containing air to the processing tank 1.
【０００８】本発明に使用する気液混合ポンプ３と同種
の遠心型ポンプとしては、従来より図３、図４に示す渦
巻式が知られているが、運転と同時にその回転羽根の水
路内が外周に向かうにつれ水路断面積が増加するため、
吐出側の流速が吸入側の流速より大となるので、真空状
態が起こりキャビテーションが発生し、図３に示す様な
矢方向の渦流の発生のためポンプ効率も低下する。As a centrifugal pump of the same kind as the gas-liquid mixing pump 3 used in the present invention, the spiral type shown in FIGS. 3 and 4 has been conventionally known. Since the cross-sectional area of the waterway increases as it goes to the outer circumference,
Since the flow velocity on the discharge side becomes higher than the flow velocity on the suction side, a vacuum state occurs and cavitation occurs, and vortex flow in the arrow direction as shown in FIG.
【０００９】一方、図５、図６に示す気液混合ポンプ３
では、特公昭５５−９５６０号公報に記載されているよ
うに、回転羽根の中心部（吸入部）より出口部（吐出
部）に向かうに従って徐々にその巾が狭くなるように吸
入側の断面積を大にし、吐出側の断面積を小とした通路
を一定間隔で設けてあるので、水路内で殆ど真空状態が
発生せず、気泡が混入した場合でもキャビテーションが
成長せず、渦流発生も無いためポンプ効率も低下しない
特徴を持っている。図５、図６で、９は回転羽根、10は
羽根本体、11は側板、12は軸孔、13はキー溝、14は細
溝、15は切欠凹部である。本図では、両吸い込み構造と
しているが、片吸い込み構造の場合でも本発明の適用に
支障がないことは言うまでもない。またポンプの材質
上、オゾンによる腐食も発生しない。On the other hand, the gas-liquid mixing pump 3 shown in FIGS.
Then, as described in Japanese Patent Publication No. 55-9560, the cross-sectional area on the suction side is such that the width gradually narrows from the central portion (suction portion) of the rotary blade toward the outlet portion (discharge portion). , And the passages with a small cross-sectional area on the discharge side are provided at regular intervals, so that a vacuum state is hardly generated in the water channel, cavitation does not grow even when bubbles are mixed, and vortex flow does not occur. Therefore, it has the characteristic that the pump efficiency does not decrease. In FIGS. 5 and 6, 9 is a rotary blade, 10 is a blade body, 11 is a side plate, 12 is a shaft hole, 13 is a key groove, 14 is a narrow groove, and 15 is a notched recess. In the present drawing, the double suction structure is adopted, but it goes without saying that the single suction structure does not hinder the application of the present invention. Also, due to the material of the pump, corrosion by ozone does not occur.
【００１０】図１に示すように、本発明では気液混合ポ
ンプ３を利用してオゾン含有空気を処理槽１の底部へ供
給しつつ、槽上部から処理すべき原水を供給してオゾン
処理を行わせる。処理槽１の形態は特に限定されるもの
ではないが、図１の実施例では槽上部のみが充填層式オ
ゾン処理部７とされ、槽下部を粒状担体が充填されてい
ない完全混合式オゾン処理部８としてある。充填槽式オ
ゾン処理部７には、例えばセラミックビーズのような粒
状担体を充填した充填層が形成されている。粒状担体の
材質は無機材質であれば、砂、焼結担体等の任意のもの
を使用できるが、活性炭のようにオゾンを分解する性質
のあるものは好ましくない。As shown in FIG. 1, in the present invention, the ozone-containing air is supplied to the bottom of the treatment tank 1 by using the gas-liquid mixing pump 3, while the raw water to be treated is supplied from the upper portion of the tank to perform the ozone treatment. Let it be done. The form of the treatment tank 1 is not particularly limited, but in the embodiment shown in FIG. 1, only the upper portion of the tank is the packed bed type ozone treatment section 7, and the lower portion of the tank is a completely mixed ozone treatment in which no granular carrier is filled. It is as part 8. The filling tank type ozone treatment unit 7 is provided with a filling layer filled with a granular carrier such as ceramic beads. As the material of the granular carrier, any material such as sand and a sintered carrier can be used as long as it is an inorganic material, but a material having a property of decomposing ozone such as activated carbon is not preferable.
【００１１】このような充填槽式オゾン処理部７と完全
混合式オゾン処理部８とを持つ処理槽１を使用すれば、
原水とオゾンとの接触が十分にしかも均一に行われ、高
いオゾン吸収率と汚濁物質の高い除去率とを両立させる
ことができる。しかし図２に示す第２の実施例のよう
に、処理槽１の内部に充填層を形成せず、槽内全体を完
全混合式オゾン処理部８としてもよい。If a processing tank 1 having such a filling tank type ozone processing section 7 and a complete mixing type ozone processing section 8 is used,
The contact between raw water and ozone is sufficient and uniform, and a high ozone absorption rate and a high pollutant removal rate can both be achieved. However, unlike the second embodiment shown in FIG. 2, the filling tank may not be formed inside the processing tank 1 and the entire tank may be the complete mixing type ozone processing unit 8.
【００１２】前述したように、本発明においては槽底部
より引き出された処理水の一部を循環水としてオゾン含
有空気と混合した後に、気液混合ポンプ３によって処理
槽底部の散気管より再び処理槽１へ戻すと同時にオゾン
含有空気を処理槽内に散気する方式を採用したことによ
り、その散気圧を低くおさえることができるので、オゾ
ン製造に必要な電力を低減しランニングコストを引き下
げることができるとともに、オゾン含有空気と処理水の
接触が繰り返されるので、オゾン吸収効率も向上する。
例えば、表１の比較のように、オゾン製造用電力量は従
来法の約７０％である２４KWH/KgO 3 に節減でき、またオ
ゾン吸収効率が８２．０％から９７．５％に向上するの
で、排ガス処理に要する亜硫酸ソーダの必要量を２８．
６g/hrから１／７〜８の３．８g/hrに減ずることができ
る。 なお、図７は従来の方法と本発明の方法とにおける
オゾン製造に必要な電力を比較したグラフであり、前記
したように散気水深が４ｍで1.5kg/cm2 の絶対圧が必要
な場合には、電力が1.5 倍程度も異なることが分かる。[0012] As described above, after mixing with ozone-containing air as circulating water part of the treated water drawn from the tank bottom in the present invention, processed by the gas-liquid mixing pump 3
At the same time, the ozone is returned to the treatment tank 1 from the diffuser at the bottom of the tank.
By adopting the method of diffusing the contained air into the treatment tank , the diffused air pressure can be kept low, so that the electric power required for ozone production can be reduced and the running cost can be reduced , and the ozone-containing air Treated water
Since the contact is repeated, the ozone absorption efficiency is also improved .
For example, as in the comparison in Table 1,
It can save about 70% of the conventional method, 24KWH / KgO 3 ,
The zonal absorption efficiency will improve from 82.0% to 97.5%.
Then, the required amount of sodium sulfite required for exhaust gas treatment is 28.
Can be reduced from 6g / hr to 3.8g / hr of 1 / 7-8
It Note that FIG. 7 is a graph comparing the power needed for ozone production in the method of the conventional method and the present invention, when air diffusion depth as described above requires absolute pressure of 1.5 kg / cm 2 at 4m Shows that the power is about 1.5 times different.
【００１３】なお、本発明における循環水とオゾン含有
空気との混合比（体積比）は、循環水100 に対してオゾ
ン含有空気が0.5 〜５程度が好ましい。0.5 未満である
とオゾン吸収効率は良いもののオゾンの供給が不足し、
５を越えると気泡径が大きくなってオゾン吸収効率が低
下するからである。The mixing ratio (volume ratio) of the circulating water and the ozone-containing air in the present invention is preferably about 0.5 to 5 for the ozone-containing air to 100 of the circulating water. If it is less than 0.5, the ozone absorption efficiency is good but the ozone supply is insufficient,
If it exceeds 5, the bubble diameter becomes large and the ozone absorption efficiency decreases.
【００１４】このような本発明の効果を確認するため、
下水二次処理水を原水として図１に示した本発明の方法
と、図９に示した従来法とによってオゾン処理を実施
し、その結果を表１に示した。In order to confirm the effects of the present invention as described above,
Ozone treatment was carried out by using the sewage secondary treated water as raw water according to the method of the present invention shown in FIG. 1 and the conventional method shown in FIG. 9, and the results are shown in Table 1.
【００１５】[0015]
【表１】 [Table 1]
【００１６】[0016]
【発明の効果】本発明は以上に説明したように、槽底部
より引き出された処理水の一部を循環水としてオゾン含
有空気と混合し、気液混合ポンプによって再び処理槽の
底部へ戻すとともにオゾン発生機の内圧を常圧に保ちつ
つ、オゾン含有空気を処理槽内に散気することによって
オゾン製造コストを低く押さえることができ、しかも優
れた処理水質を達成することができるものであるから、
従来の問題点を解消した水のオゾン処理法として、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。According to the present invention as described above, together with a portion of the treated water drawn from the tank bottom was mixed with ozone-containing air as circulating water back to the bottom again the processing tank by the gas-liquid mixing pump Keeping the internal pressure of the ozone generator at normal pressure
By diffusing ozone-containing air into the treatment tank, the ozone production cost can be kept low, and excellent treated water quality can be achieved.
As a method of ozone treatment of water that solves the conventional problems, it greatly contributes to the development of industry.
【図１】本発明の第１の実施例を説明する断面図であ
る。FIG. 1 is a cross-sectional view illustrating a first embodiment of the present invention.
【図２】本発明の第２の実施例を説明する断面図であ
る。FIG. 2 is a cross-sectional view illustrating a second embodiment of the present invention.
【図３】従来一般の遠心型ポンプの回転軸と垂直方向の
断面図である。FIG. 3 is a sectional view of a conventional general centrifugal pump in a direction perpendicular to a rotation axis.
【図４】従来一般の遠心型ポンプの回転軸を含む平面で
切断した断面図である。FIG. 4 is a cross-sectional view taken along a plane including a rotary shaft of a conventional general centrifugal pump.
【図５】本発明において用いられる気液混合ポンプの回
転軸と垂直方向の断面図である。FIG. 5 is a cross-sectional view of a gas-liquid mixing pump used in the present invention in a direction perpendicular to a rotation axis.
【図６】本発明において用いられる気液混合ポンプの回
転軸を含む平面で切断した断面図である。FIG. 6 is a cross-sectional view taken along a plane including the rotation axis of the gas-liquid mixing pump used in the present invention.
【図７】オゾン製造に必要な電力消費量を示すグラフで
ある。FIG. 7 is a graph showing the power consumption required for ozone production.
【図８】従来法を説明する断面図である。FIG. 8 is a sectional view illustrating a conventional method.
【図９】他の従来法を説明する断面図である。FIG. 9 is a cross-sectional view illustrating another conventional method.
【符号の説明】 １ 処理槽 ２ オゾン発生機 ３ 気液混合ポンプ６ 散気管 [Explanation of symbols] 1 treatment tank 2 ozone generator 3 gas-liquid mixing pump 6 air diffuser
Claims (1)
るオゾン含有空気を送気しつつ処理槽上部より原水を供
給して有機物や臭気等の分解を行わせる水のオゾン処理
法において、槽底部より引き出された処理水の一部をオ
ゾン含有空気と混合した後、気液混合ポンプによって処
理槽底部の散気管に圧送してオゾン発生機の内圧を常圧
に保ちつつ、該オゾン含有空気を処理槽内に散気すると
同時に該混合処理水を該散気管より処理槽に返送するこ
とを特徴とする水のオゾン処理法。1. Obtained from an ozone generator from the bottom of the treatment tank
In the ozone treatment method of water in which raw water is supplied from the top of the treatment tank to decompose organic substances and odors while supplying ozone-containing air, a part of the treated water drawn from the bottom of the tank is > after mixing with ozone-containing air, punished by the gas-liquid mixing pump
The internal pressure of the ozone generator is kept at normal pressure by pumping it to the air diffuser at the bottom of the processing tank.
When the ozone-containing air is diffused into the treatment tank while maintaining
Ozone treatment of water, wherein the this <br/> returning the mixture treated water into the processing tank from the diverging pipe simultaneously.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3204930A JP2539555B2 (en) | 1991-07-20 | 1991-07-20 | Water ozonation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3204930A JP2539555B2 (en) | 1991-07-20 | 1991-07-20 | Water ozonation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0523683A JPH0523683A (en) | 1993-02-02 |
| JP2539555B2 true JP2539555B2 (en) | 1996-10-02 |
Family
ID=16498711
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3204930A Expired - Fee Related JP2539555B2 (en) | 1991-07-20 | 1991-07-20 | Water ozonation method |
Country Status (1)
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| JP (1) | JP2539555B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2014240043A (en) * | 2013-06-11 | 2014-12-25 | 株式会社東芝 | Water treatment system |
| JP5936743B1 (en) * | 2015-05-13 | 2016-06-22 | 株式会社日立製作所 | Organic substance decomposition apparatus and organic substance decomposition method |
| JP6594030B2 (en) * | 2015-05-13 | 2019-10-23 | 株式会社日立製作所 | Organic substance decomposition apparatus and organic substance decomposition method |
| JP6607828B2 (en) * | 2016-06-17 | 2019-11-20 | 株式会社日立製作所 | Organic substance decomposition apparatus and organic substance decomposition method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5395178A (en) * | 1977-01-31 | 1978-08-19 | Sumitomo Precision Prod Co | Ozone treating reaction apparatus |
| JPS559560A (en) * | 1978-07-05 | 1980-01-23 | Nippon Electric Co | Programable oscillator |
-
1991
- 1991-07-20 JP JP3204930A patent/JP2539555B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0523683A (en) | 1993-02-02 |
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