JP3446401B2 - Ozone treatment method and treatment device for sewage sludge - Google Patents
Ozone treatment method and treatment device for sewage sludgeInfo
- Publication number
- JP3446401B2 JP3446401B2 JP15887795A JP15887795A JP3446401B2 JP 3446401 B2 JP3446401 B2 JP 3446401B2 JP 15887795 A JP15887795 A JP 15887795A JP 15887795 A JP15887795 A JP 15887795A JP 3446401 B2 JP3446401 B2 JP 3446401B2
- Authority
- JP
- Japan
- Prior art keywords
- ozone
- sludge
- reaction tube
- contact tank
- 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 - Fee Related
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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
- Y02W10/30—Wastewater or sewage treatment systems using renewable energies
- Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy
Landscapes
- Treatment Of Sludge (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明はオゾンを用いて下水汚泥
処理を行うことによって効率的に殺菌、脱臭及び脱色処
理を行うようにした下水汚泥のオゾン処理方法と装置に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for treating sewage sludge with ozone, which is capable of efficiently performing sterilization, deodorization and decolorization by treating ozone with sewage sludge.
【０００２】[0002]
【従来の技術】従来から汚泥の処理は種々の分野で必要
とされており、例えば都市下水処理場における水処理施
設で発生した余剰汚泥とか最初沈澱池で発生した生汚泥
は、水処理施設の系外に引き抜かれて汚泥処理施設に輸
送され、濃縮，消化，脱水等の工程を経て最終処分が行
われる。特に大都市圏においては、人口の集中等の要因
により複数の下水処理場が近接している場合が多く、こ
れら各下水処理場の発生汚泥を一カ所に集中して汚泥の
集約処理を行うことによって汚泥処理時間を短縮し、且
つ汚泥処理コストを低くすることができる。2. Description of the Related Art Conventionally, sludge treatment has been required in various fields. For example, excess sludge generated in a water treatment facility in an urban sewage treatment plant or raw sludge generated in a first settling pond is treated in a water treatment facility. It is drawn out of the system and transported to a sludge treatment facility, where it undergoes processes such as concentration, digestion and dehydration for final disposal. Especially in metropolitan areas, there are many cases where multiple sewage treatment plants are close to each other due to factors such as population concentration, and sludge generated from each of these sewage treatment plants should be concentrated in one place for intensive sludge treatment. Thus, the sludge treatment time can be shortened and the sludge treatment cost can be reduced.
【０００３】上記集約処理の各種方法を図６に基づいて
説明すると、（１）は生汚泥を濃縮，消化後に最終処分
もしくは天日乾燥を経て最終処分する方法、（２）は生
汚泥を濃縮後に調整、もしくは消化，調整後に機械脱水
し、コンポスト化してから最終処分する方法、（３）は
生汚泥を濃縮後に調整、もしくは消化，調整後に機械脱
水し、最終処分もしくは乾燥，焼却してから最終処分す
る方法、（４）は生汚泥を濃縮，熱処理後に機械脱水
し、焼却してから最終処分する方法、（５）は生汚泥を
濃縮，湿式酸化後に機械脱水してから最終処分する方法
である（下水道施設設計指針と解説の第４２３ページ，
１９８４年版，（社）日本下水道協会発行を参照）。Various methods of the above-mentioned intensive treatment will be described with reference to FIG. 6. (1) is a method of concentrating raw sludge and finally disposing after digestion or final disposal after sun drying, and (2) is concentrating raw sludge. After adjusting, or after digesting and adjusting, mechanically dehydrating and composting, and then final disposal, (3) is adjusted after concentrating the raw sludge, or after digestion and adjustment, mechanically dehydrated, and finally disposed of or dried and incinerated. Method of final disposal, (4) method of concentrating raw sludge, mechanical dehydration after heat treatment, incineration and final disposal, (5) method of concentrating raw sludge, mechanical dehydration after final oxidation, and final disposal (Page 423 of Sewerage Facility Design Guidelines and Explanations,
See 1984 edition, published by the Japan Sewer Association).
【０００４】上記の最終処分の方法として従来は 焼却
後に埋立用として使用する手段が多用されているが、近
年ではエネルギー源とか建築資材等への有効利用がはか
られている現状にある。As the above-mentioned final disposal method, conventionally, a means used for landfill after incineration has been widely used, but in recent years, effective utilization for an energy source, a construction material and the like has been attempted.
【０００５】汚泥の集約処理を行うには、各処理場にて
発生する汚泥を集中汚泥処理場に輸送する必要があり、
その輸送方法としてはトラック輸送、船舶輸送、パイプ
輸送等が考えられるが、特に下水汚泥のパイプ輸送を行
う場合には、輸送中に下水汚泥が腐敗及び変質する惧れ
がある。In order to carry out an integrated treatment of sludge, it is necessary to transport the sludge generated in each treatment plant to the central sludge treatment plant,
The transportation method may be truck transportation, ship transportation, pipe transportation, or the like. However, particularly when pipe transportation of sewage sludge is performed, there is a possibility that the sewage sludge will be decomposed or deteriorated during transportation.
【０００６】上記に対処して、先に本出願人は特願平４
−２３８７５６号によって汚泥が流通する汚泥輸送管内
にオゾンを供給し、汚泥とオゾンとを接触反応させて汚
泥を輸送するようにした方法と装置を提案しており、更
に特願平４−３１５４６６号によって汚泥処理槽内にオ
ゾンを供給し、汚泥とオゾンとを接触反応させて汚泥の
処理を行った後に送泥管で輸送する汚泥処理方法及び装
置を提案している。In response to the above, the present applicant has previously filed Japanese Patent Application No.
No. 238756 proposes a method and apparatus for supplying ozone into a sludge transport pipe through which sludge flows, and carrying out contact reaction between sludge and ozone to transport sludge, and Japanese Patent Application No. 4-315466. Proposes a sludge treatment method and apparatus in which ozone is supplied to the sludge treatment tank, sludge and ozone are brought into contact with each other to treat sludge, and then sludge is transported by a sludge pipe.
【０００７】[0007]
【発明が解決しようとする課題】しかしながら図６に示
した汚泥の各種集約処理方法の場合、汚泥中に生息する
バクテリア等の微生物群の種類とか勢力は処理工程での
環境に大きく左右され、消化槽を除いてほとんど人為的
操作を施すことができない。従って硫酸塩還元菌等の作
用による汚泥の腐敗現象が発生する等の問題点が生じ易
く、このことが汚泥の有効利用をはかる上での障害にな
るという課題があった。However, in the case of the various sludge sludge treatment methods shown in FIG. 6, the type and power of microorganisms such as bacteria inhabiting sludge greatly depend on the environment in the treatment process, and Except for the tank, almost no artificial operation can be performed. Therefore, there is a problem that a problem such as spoilage of sludge due to the action of sulfate-reducing bacteria is likely to occur, which is an obstacle to effective utilization of sludge.
【０００８】更にパイプ輸送等により汚泥の集約処理を
行う場合には、輸送管内は嫌気状態となり、嫌気性微生
物の繁殖等によって下水汚泥の腐敗の進行が早くなる
上、輸送管内の沈積物等が下水汚泥の腐敗や変質を進め
る要因になり、汚泥の腐敗や変質が進むことによって集
中汚泥処理時に汚泥の沈降性とか脱水性が悪化してしま
い、集約後の汚泥処理を安定に行うことが困難となって
濃縮、脱水等の汚泥処理工程において悪臭の発生量が増
加し、作業環境が悪化するという問題点が発生する。Further, when sludge is intensively processed by pipe transportation or the like, the inside of the transportation pipe becomes anaerobic, the decay of the sewage sludge is accelerated due to the propagation of anaerobic microorganisms, and the deposits in the transportation pipe are It becomes a factor that promotes the deterioration and deterioration of sewage sludge, and the deterioration and deterioration of sludge during concentrated sludge treatment deteriorates as the deterioration and deterioration of sludge progresses, making it difficult to perform stable sludge treatment after aggregation. As a result, the amount of offensive odor is increased in the sludge treatment process such as concentration and dehydration, which causes a problem that the working environment is deteriorated.
【０００９】上記に対処して、前記特願平４−３１５４
６６号によって提案したように汚泥処理槽内にオゾンガ
スを供給し、被処理水としての汚泥とオゾンとを接触反
応させた後に送泥管で輸送するようにした汚泥処理方法
と装置を採用することによって所望とするオゾン処理効
果が得られているが、このようなオゾン処理法としては
一般にオゾン接触槽の底壁近傍に配置した孔径数百μｍ
の多孔質体で構成された散気管からオゾンガスを被処理
水中に放散して、オゾンガス気泡の上昇に伴って水とオ
ゾンとを接触反応させる手段が採用されている。In response to the above, Japanese Patent Application No. 4-3154
Adopting a sludge treatment method and device, as proposed by No. 66, in which ozone gas is supplied into a sludge treatment tank, sludge as treated water and ozone are contact-reacted, and then transported by a mud pipe. Although the desired ozone treatment effect has been obtained by such a method, such an ozone treatment method generally has a pore diameter of several hundred μm arranged near the bottom wall of the ozone contact tank.
The means for diffusing ozone gas into the water to be treated from the air diffusing tube composed of the porous body and causing the water and ozone to react with each other as the ozone gas bubbles rise is adopted.
【００１０】しかし対象となる被処理水が多量の汚泥粒
子を含有している場合には、上記散気管の孔部が目詰ま
り等を起こして閉塞してしまうことが多々あり、オゾン
処理効率が径時的に劣化してしまう外に散気管自体を頻
繁に交換する必要があってメンテナンスとかコストの面
での問題点が残存している。However, when the target water to be treated contains a large amount of sludge particles, the holes of the air diffuser often become clogged and clogged, resulting in ozone treatment efficiency. In addition to the deterioration over time, it is necessary to frequently replace the air diffuser itself, and there remain problems in terms of maintenance and cost.
【００１１】そこで本発明は上記の問題点に鑑みてなさ
れたものであって、汚泥処理におけるオゾン処理効率と
メンテナンスの向上及びコストの低減化に寄与すること
を目的とするものである。Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to contribute to improvement of ozone treatment efficiency in sludge treatment, maintenance, and cost reduction.
【００１２】[0012]
【課題を解決するための手段】本発明は上記の課題を解
決するために、下水汚泥を密閉型のオゾン接触槽に流入
して、オゾンガスを汚泥中に放散することによって殺
菌、脱臭及び脱色処理を行うようにした下水汚泥のオゾ
ン処理において、上記オゾン接触槽の上部に、該オゾン
接触槽の上壁を貫通して嵌入されているとともに下端部
をオゾン接触槽内の汚泥水位に一致した状態として縦方
向に固定された縦型の反応管を設け、循環ポンプの駆動
によってオゾン接触槽内の汚泥を循環経路を介して該反
応管の上方部に送り込むと同時にオゾン発生機から得ら
れるオゾンガスを該反応管の上部から導入することによ
り、反応管内で汚泥とオゾンとを下降流として接触反応
させてオゾン接触槽内に流入させるようにした下水汚泥
のオゾン処理方法と装置をその実現手段としている。In order to solve the above problems, the present invention sterilizes, deodorizes and decolorizes sewage sludge by flowing it into a closed ozone contact tank to diffuse ozone gas into the sludge. In the ozone treatment of the sewage sludge, the state in which the upper end of the ozone contact tank is fitted through the upper wall of the ozone contact tank and the lower end matches the sludge water level in the ozone contact tank. As a vertical reaction tube fixed in the vertical direction is provided, the sludge in the ozone contact tank is sent to the upper part of the reaction tube through the circulation path by driving the circulation pump, and at the same time, ozone gas obtained from the ozone generator is supplied. A method for ozone treatment of sewage sludge, wherein sludge and ozone are brought into contact with each other as a descending flow in the reaction tube and introduced into the ozone contact tank by introducing from the upper part of the reaction tube. It has as its implementation means a location.
【００１３】又、前記縦型の反応管の上部に汚泥貯留槽
を設けて、オゾン接触槽内の汚泥を循環ポンプ及び循環
経路を介して上方に引き上げて汚泥貯留槽内に一旦流入
させた後、供給された汚泥をオゾンとともに反応管内を
下降流として自然落下させた方法と、オゾン接触槽内の
反応で消費されずに残ったオゾンガスを排オゾンガスと
して引き抜き、その一部を反応管に注入オゾンガスとと
もに注入する方法を提供する。更に前記縦型の反応管の
形状を、スパイラル型（渦流状）もしくはジグザク構造
としてオゾンとの接触効率を高めた方法を提供する。Further, after a sludge storage tank is provided above the vertical reaction tube, sludge in the ozone contact tank is pulled upward through a circulation pump and a circulation path to once flow into the sludge storage tank. , A method in which the supplied sludge was allowed to fall naturally along with the ozone in the reaction tube by a downward flow, and the ozone gas remaining without being consumed by the reaction in the ozone contact tank was extracted as exhaust ozone gas and part of it was injected into the reaction tube. Provide a method of injecting with. Further, a method is provided in which the vertical reaction tube is formed in a spiral (vortex) shape or a zigzag structure to enhance the contact efficiency with ozone.
【００１４】[0014]
【作用】かかる下水汚泥のオゾン処理方法及び処理装置
によれば、オゾン接触槽内に貯留された汚泥が循環ポン
プの駆動に伴って循環経路を経由して反応管の上側部に
まで引き上げられ、同時にオゾン発生機から得られるオ
ゾンガスを吸引しながら該オゾンガスともに反応管内を
下降流として流れ、この下降時の混合作用によりオゾン
ガスと汚泥とが充分に接触する。特に反応管内に注入さ
れたオゾンガスは下降する汚泥液流量とのバランスによ
って均一な気泡となって流下し、汚泥とオゾンガスとの
混合液がオゾン接触槽内の底壁近傍まで深く潜入して槽
内の汚泥が撹拌され、オゾン接触反応が促進される。そ
してオゾンガスの持つ強い酸化力と殺菌力によって汚泥
の殺菌、脱臭及び脱色処理が行われる。According to the method and apparatus for treating ozone of sewage sludge, sludge stored in the ozone contact tank is pulled up to the upper side of the reaction tube via the circulation route as the circulation pump is driven, At the same time, while sucking the ozone gas obtained from the ozone generator, the ozone gas flows together with the ozone gas in a downward flow in the reaction tube, and due to the mixing action during the downward movement, the ozone gas and the sludge are sufficiently brought into contact with each other. In particular, the ozone gas injected into the reaction tube flows down as uniform bubbles due to the balance with the descending sludge liquid flow rate, and the mixed liquid of sludge and ozone gas deeply infiltrates to the vicinity of the bottom wall in the ozone contact tank, The sludge is stirred and the ozone contact reaction is promoted. The sludge is sterilized, deodorized and decolorized by the strong oxidizing and sterilizing power of ozone gas.
【００１５】又、縦型の反応管の上部に汚泥貯留槽を設
けてオゾン接触槽内の汚泥を循環ポンプ及び循環経路を
介して引き上げてから汚泥貯留槽内に一旦流入させる
と、オゾン反応槽内は大気圧であるために汚泥は反応管
内を下降流として自然落下し、この時に生じる吸引力に
よってオゾンガスが反応管内に引き込まれて所望とする
オゾン接触反応が進行する。Further, if a sludge storage tank is provided above the vertical reaction tube and the sludge in the ozone contact tank is pulled up through the circulation pump and the circulation path and then once introduced into the sludge storage tank, the ozone reaction tank Since the inside is atmospheric pressure, the sludge naturally falls as a downward flow in the reaction tube, and the ozone gas is drawn into the reaction tube by the suction force generated at this time, and the desired ozone contact reaction proceeds.
【００１６】オゾン接触槽内の反応で消費されずに残っ
たオゾンガスを排オゾンガスとして引き抜き、その一部
を反応管に注入すると、排オゾンガスはオゾンを分解し
た後に大気中に放散されるために反応管内の圧力が大気
圧となって汚泥の自然流下流量と循環汚泥の流量、発生
オゾンガスとの流量のバランスが良好になり、排オゾン
ガスを再利用できることから効率的なオゾンガスの利用
を可能とする。The ozone gas left unconsumed in the reaction in the ozone contact tank is extracted as exhaust ozone gas, and a part of the ozone gas is injected into the reaction tube. The exhaust ozone gas is decomposed into ozone and then released into the atmosphere. The pressure in the pipe becomes atmospheric pressure, and the balance between the natural flow rate of sludge, the flow rate of circulating sludge, and the flow rate of generated ozone gas is improved, and the exhaust ozone gas can be reused, which enables efficient use of ozone gas.
【００１７】上記反応管の形状をスパイラル型（渦流
状）もしくはジグザク構造にしたことにより、同じ高さ
の直管型反応管を流れるのと同じ流量での管の長さ、即
ち、気液接触時間を長くすることができて、オゾン接触
反応が高められる。By making the shape of the above-mentioned reaction tube a spiral type (vortex type) or a zigzag structure, the length of the tube at the same flow rate as that in a straight type reaction tube of the same height, that is, gas-liquid contact The time can be extended and the ozone contact reaction is enhanced.
【００１８】[0018]
【実施例】以下に本発明にかかる下水汚泥の処理方法及
び処理装置の具体的な実施例について説明する。図１は
本実施例にかかる下水汚泥の連続オゾン処理システムの
概要図であり、図中の１は汚泥流入渠、２は水中ポン
プ、３は汚泥中継槽であり、この汚泥中継槽３には撹拌
機構４とｐＨ計５、ＯＲＰ計（酸化還元電位計）６及び
水位のレベル計７が配備されている。[Examples] Specific examples of the method and apparatus for treating sewage sludge according to the present invention will be described below. FIG. 1 is a schematic diagram of a continuous ozone treatment system for sewage sludge according to the present embodiment. In the figure, 1 is a sludge inflow conduit, 2 is an underwater pump, 3 is a sludge relay tank, and this sludge relay tank 3 has A stirring mechanism 4, a pH meter 5, an ORP meter (oxidation-reduction potentiometer) 6 and a water level meter 7 are provided.
【００１９】８は汚泥供給ポンプ、９は密閉型のオゾン
接触槽、１０は循環ポンプ、１１はオゾン発生機、１２
は反応管であり、この反応管１２はオゾン接触槽１の上
壁を貫通して嵌入されているとともに、下端部がオゾン
接触槽９内の汚泥水位に一致した状態として縦方向に固
定されている。そして汚泥供給ポンプ８又は循環ポンプ
１０の駆動によって汚泥が循環経路２０を介して該反応
管１２の上方部に送り込まれるのと同時に、オゾン発生
機１１から得られるオゾンガスが反応管１２の上部から
導入されるように構成されている。Reference numeral 8 is a sludge supply pump, 9 is a closed ozone contact tank, 10 is a circulation pump, 11 is an ozone generator, and 12 is an ozone generator.
Is a reaction tube, and the reaction tube 12 is fitted through the upper wall of the ozone contact tank 1 and is fixed in the vertical direction so that the lower end of the reaction tube 12 matches the sludge water level in the ozone contact tank 9. There is. Then, by driving the sludge supply pump 8 or the circulation pump 10, the sludge is sent to the upper part of the reaction tube 12 through the circulation path 20, and at the same time, the ozone gas obtained from the ozone generator 11 is introduced from the upper part of the reaction tube 12. It is configured to be.
【００２０】１３は液位調整槽、１４は計測槽であり、
この計測槽１４には撹拌機構１５とｐＨ計１６及びＯＲ
Ｐ計１７が配備されている。１８は濃縮槽、１９は排オ
ゾン処理施設である。13 is a liquid level adjusting tank, 14 is a measuring tank,
The measuring tank 14 includes a stirring mechanism 15, a pH meter 16 and an OR.
A total of 17 P are provided. Reference numeral 18 is a concentrating tank, and 19 is an exhaust ozone treatment facility.
【００２１】かかる本実施例の作用を以下に説明する
と、先ず汚泥流入渠１から水中ポンプ２によって汲み上
げられた汚泥が汚泥中継槽３に貯留される。汚泥中継槽
３では撹拌機構４によって汚泥を常時撹拌しながらｐＨ
計７とＯＲＰ計６によってｐＨとＯＲＰ（酸化還元電
位）が連続的に測定される。酸化還元電位は液の酸化力
あるいは還元力の強さを知る指標であり、特に嫌気性処
理プロセスでの操作条件を管理する際に有効に用いられ
る。The operation of this embodiment will be described below. First, the sludge pumped by the submersible pump 2 from the sludge inlet 1 is stored in the sludge relay tank 3. In the sludge relay tank 3, the pH of the sludge is constantly stirred by the stirring mechanism 4 while stirring the sludge.
The pH and ORP (oxidation-reduction potential) are continuously measured by the meter 7 and the ORP meter 6. The redox potential is an index for knowing the strength of the oxidizing power or the reducing power of a liquid, and is effectively used especially when controlling the operating conditions in the anaerobic treatment process.
【００２２】そしてレベル計７によって汚泥中継槽３内
での水位が所定のレベルに確保されたことが検出される
と、汚泥供給ポンプ８が作動を開始してオゾン接触槽９
の循環経路２０に一定流量の汚泥が供給され、反応管１
２を下降流として通過してオゾン接触槽９内に流入す
る。When the level meter 7 detects that the water level in the sludge relay tank 3 is maintained at a predetermined level, the sludge supply pump 8 starts operating and the ozone contact tank 9 is activated.
A certain amount of sludge is supplied to the circulation path 20 of the reaction tube 1
2 as a downward flow and flows into the ozone contact tank 9.
【００２３】次にオゾン接触槽９内に貯留された汚泥
は、循環ポンプ１０の駆動に伴って循環経路２０を経由
して一定流量だけ反応管１２の上側部にまで引き上げら
れ、これと同時にオゾン発生機１１を駆動することによ
って発生するオゾンガスを吸引しながら、該オゾンガス
ともに反応管１２内を下降流として流れるが、この下降
時の混合作用により該オゾンガスと汚泥とが充分に接触
する。Next, the sludge stored in the ozone contact tank 9 is pulled up to the upper portion of the reaction tube 12 by a constant flow rate through the circulation path 20 as the circulation pump 10 is driven, and at the same time, the ozone is simultaneously discharged. While the ozone gas generated by driving the generator 11 is sucked, the ozone gas flows together with the ozone gas as a downward flow in the reaction tube 12, and the ozone gas and the sludge are sufficiently brought into contact with each other due to the mixing action at the time of the downward movement.
【００２４】このようにしてオゾン反応槽９と循環経路
２０及び反応管１２内を循環してオゾンガスと接触した
汚泥は液位調整槽１３で一定の水位に調整され、次段の
計測槽１４へ自然流下によって送り込まれる。In this way, the sludge circulating in the ozone reaction tank 9, the circulation path 20 and the reaction tube 12 and brought into contact with ozone gas is adjusted to a constant water level by the liquid level adjusting tank 13 and is sent to the next measuring tank 14. It is sent by natural flow.
【００２５】計測槽１４では、撹拌機構１５によって常
時撹拌しながらｐＨ計１６、ＯＲＰ計１７によって連続
的にｐＨと酸化還元電位が測定され、次に汚泥は濃縮槽
１８に送り込まれて重力濃縮に基づいて濃縮層１８ａと
上澄み液１８ｂとに分離される。この上澄み液は返流水
２１として下水処理工程に戻され、濃縮汚泥２２は脱水
工程などの次工程へ送り込まれる。又、オゾン接触槽９
で反応に使われずに排出されるオゾンガスは排オゾン処
理施設１９に送り込まれ、基準値以下に分解された後に
大気中に放散される。In the measuring tank 14, the pH meter 16 and the ORP meter 17 continuously measure the pH and the oxidation-reduction potential while continuously stirring by the stirring mechanism 15, and then the sludge is sent to the thickening tank 18 for gravity concentration. Based on this, the concentrated layer 18a and the supernatant 18b are separated. This supernatant liquid is returned to the sewage treatment step as return water 21, and the concentrated sludge 22 is sent to the next step such as a dehydration step. Also, ozone contact tank 9
The ozone gas discharged without being used in the reaction is sent to the waste ozone treatment facility 19, decomposed to below the standard value, and then released into the atmosphere.
【００２６】図１の実施例によれば、オゾン接触槽９に
送り込まれる汚泥を連続的にオゾン処理することができ
る。これを更に説明すると、反応管１２内に注入された
オゾンガスは、下降する汚泥液流量とのバランスによっ
て均一な気泡となってから汚泥と接触しながら流下し、
汚泥とオゾンガスとの混合液は、矢印ａに示したように
オゾン接触槽９内の底壁近傍まで深く潜入することによ
って槽内の汚泥の撹拌作用をもたらしてオゾン反応の進
行が促進される。尚、本装置は汚泥のみに限定されず、
オゾン処理が行われるあらゆる対象水に対して適用可能
である。According to the embodiment shown in FIG. 1, the sludge fed into the ozone contact tank 9 can be continuously ozone-treated. To further explain this, the ozone gas injected into the reaction tube 12 becomes uniform bubbles due to the balance with the descending sludge liquid flow rate, and then flows down while contacting the sludge,
The mixed liquid of sludge and ozone gas deeply infiltrates to the vicinity of the bottom wall in the ozone contact tank 9 as shown by the arrow a, thereby causing a stirring action of the sludge in the tank and promoting the progress of the ozone reaction. This device is not limited to sludge,
It can be applied to all target water to be treated with ozone.
【００２７】次に図２〜図５に基づいて、本実施例で採
用した各種オゾン接触槽の具体的な実施例を説明する。Next, specific examples of various ozone contact tanks used in this example will be described with reference to FIGS.
【００２８】〔実施例１〕本実施例では、図２に示した
ように縦型の反応管１２の上部に汚泥貯留槽２３を設け
て、オゾン接触槽９内の汚泥を循環ポンプ１０及び循環
経路２０を介して上方に引き上げて汚泥貯留槽２３内に
一旦流入させる。オゾン反応槽９内は大気圧であるた
め、上部に供給された汚泥は反応管１２内を下降流とし
て自然落下する。この落下する際に生じる吸引力を利用
してオゾン発生機から得られたオゾンガスＯ3が反応管
１２内に引き込まれ、所望とするオゾン接触反応が進行
する。[Embodiment 1] In the present embodiment, as shown in FIG. 2, a sludge storage tank 23 is provided above the vertical reaction tube 12, and the sludge in the ozone contact tank 9 is circulated by the circulation pump 10 and the circulation tank 10. It is pulled up through the path 20 and once made to flow into the sludge storage tank 23. Since the ozone reaction tank 9 is at atmospheric pressure, the sludge supplied to the upper part naturally falls in the reaction tube 12 as a downward flow. Ozone gas O 3 obtained from the ozone generator is drawn into the reaction tube 12 by utilizing the suction force generated when it falls, and the desired ozone contact reaction proceeds.
【００２９】縦型の反応管１２内を落下する汚泥の流量
は、該反応管１２の上部から下端出口までの水位差と、
注入されるオゾンガスの流量とによって決定され、これ
と釣り合う流量の汚泥を循環ポンプ１０によって供給す
れば安定した下降流を得ることができる。The flow rate of sludge falling in the vertical reaction tube 12 depends on the water level difference from the upper part of the reaction tube 12 to the lower end outlet.
It is determined by the flow rate of the ozone gas to be injected, and if a sludge of a flow rate that is in balance with this is supplied by the circulation pump 10, a stable downward flow can be obtained.
【００３０】〔実施例２〕図３に示したように、本実施
例では図２の構成に加えてオゾン接触槽９内の反応で消
費されずに残ったオゾンガスを排オゾンガスとして引き
抜き、その一部をチューブ２４を用いて反応管１２に注
入オゾンガスＯ3とともに注入する。排オゾンガスはオ
ゾンを分解した後に大気中に放散されるため、反応管１
２内の圧力は大気圧となって汚泥の自然流下流量と循環
汚泥の流量、発生オゾンガスＯ3との流量のバランスを
良好にとることができる。又、排オゾンガスを再利用で
きることから効率的にオゾンガスを消費することができ
る。[Embodiment 2] As shown in FIG. 3, in this embodiment, in addition to the configuration of FIG. 2, the ozone gas remaining without being consumed by the reaction in the ozone contact tank 9 is extracted as exhaust ozone gas. The portion is injected into the reaction tube 12 using the tube 24 together with the injected ozone gas O 3 . Since the exhaust ozone gas is released into the atmosphere after decomposing ozone, the reaction tube 1
The pressure in 2 becomes atmospheric pressure, and the natural flow rate of sludge, the flow rate of circulating sludge, and the flow rate of generated ozone gas O 3 can be well balanced. Moreover, since the exhaust ozone gas can be reused, the ozone gas can be efficiently consumed.
【００３１】〔実施例３〕図４に示したように、本実施
例では反応管１２ａの形状をスパイラル型（渦流状）と
したことが特徴となっている。その他の構成は図２に示
す実施例１と同様である。[Embodiment 3] As shown in FIG. 4, the present embodiment is characterized in that the shape of the reaction tube 12a is spiral (vortex flow). Other configurations are similar to those of the first embodiment shown in FIG.
【００３２】縦型の反応管１２によって安定した気液下
降流を得るためには、該反応管１２内を下降流として流
下する液の流量と等しい液流量を循環ポンプ１０によっ
て上部に供給しなければならない。反応管１２を流下す
る液の流量は、この反応管１２の入口と出口の水位差に
比例するので、気液接触時間を長くとりたいときには、
反応管１２の上下長を大にすればよいが、その分多くの
流量が必要になってくる。そこで反応管１２の形状をス
パイラル型とすることによって同じ高さの直管型反応管
１２を流れるのと同じ流量での管の長さ、即ち、気液接
触時間を長くすることができて、オゾン接触反応を高め
ることができる。In order to obtain a stable gas-liquid downward flow by the vertical reaction tube 12, a liquid flow rate equal to the flow rate of the liquid flowing down as a downward flow in the reaction tube 12 must be supplied to the upper part by the circulation pump 10. I have to. Since the flow rate of the liquid flowing down the reaction tube 12 is proportional to the difference in water level between the inlet and the outlet of the reaction tube 12, when it is desired to increase the gas-liquid contact time,
Although it is sufficient to increase the vertical length of the reaction tube 12, a large flow rate is required accordingly. Therefore, by making the shape of the reaction tube 12 spiral, it is possible to increase the length of the tube at the same flow rate as that in the straight reaction tube 12 of the same height, that is, the gas-liquid contact time, The ozone contact reaction can be enhanced.
【００３３】〔実施例４〕図５に示したように、本実施
例では反応管１２ｂの形状をジグザグ構造としたことが
特徴となっている。その他の構成は図２に示す実施例１
と同様である。この例の場合でも反応管１２の形状をス
パイラル型とすることによって同じ高さの直管型反応管
１２を流れるのと同じ流量での管の長さ、即ち、気液接
触時間を長くすることができる。[Embodiment 4] As shown in FIG. 5, the present embodiment is characterized in that the shape of the reaction tube 12b is a zigzag structure. Other configurations are shown in FIG.
Is the same as. Even in the case of this example, by making the shape of the reaction tube 12 spiral, the length of the tube at the same flow rate as flowing through the straight reaction tube 12 of the same height, that is, the gas-liquid contact time is lengthened. You can
【００３４】本実施例の動作態様を要約すると以下の通
りである。即ち、一般に気相と液相とを効率的に接触さ
せるために気泡塔が用いられる。本発明の汚泥のオゾン
処理装置は、気液下降流型気泡塔の形式をとったことが
特徴となっている。The operation mode of this embodiment is summarized as follows. That is, generally, a bubble column is used to efficiently contact the gas phase and the liquid phase. The sludge ozone treatment apparatus of the present invention is characterized in that it takes the form of a gas-liquid downward flow type bubble column.
【００３５】この気液下降流型気泡塔では、液の下降流
により気泡を浮力方向とは反対の下向きに流すので、気
泡の塔内滞留時間が長くなり、ガスを上向きに流す気液
上向き向流式あるいは並流式気泡塔に比べて気液接触効
率が高くなる。又、液の流量に対してガスの流量の割合
が増えるに従って大気泡が形成され、安定な気液下降流
が得られなくなる。In this gas-liquid downward flow type bubble column, since the bubbles flow downward in the direction opposite to the buoyancy direction due to the downward flow of the liquid, the retention time of the bubbles in the column becomes long, and the gas flows upward in the gas-liquid upward direction. The gas-liquid contact efficiency is higher than that of the flow type or co-current type bubble column. Further, as the ratio of the gas flow rate to the liquid flow rate increases, large bubbles are formed and a stable gas-liquid downward flow cannot be obtained.
【００３６】気液下降流を得るための原理を以下に述べ
ると、オゾン接触槽中の汚泥を循環ポンプによって引き
抜き、槽上部に揚水する。揚水された汚泥は下降管内を
自然落下し、再びオゾン接触槽内へ戻される。液の落下
流によって生じる吸引力を利用してオゾン発生機から送
気されるオゾンガスをチューブを用いて引き込むことに
より、液とともにオゾンガスが気泡化して流下し、気液
下降流を得ることができる。流下したオゾンガスと汚泥
の混合流はオゾン接触槽内に深く潜入し、該接触槽内の
汚泥の撹拌作用が同時に得られる。The principle for obtaining the gas-liquid descending flow will be described below. Sludge in the ozone contact tank is drawn out by a circulation pump and pumped to the upper part of the tank. The pumped sludge naturally falls in the downcomer and is returned to the ozone contact tank again. By using the tube to draw in the ozone gas sent from the ozone generator using the suction force generated by the falling flow of the liquid, the ozone gas is bubbled and flows down together with the liquid, and a gas-liquid downward flow can be obtained. The mixed flow of the ozone gas and the sludge that has flowed down deeply penetrates into the ozone contact tank, and the stirring action of the sludge in the contact tank can be obtained at the same time.
【００３７】特に下降管内及び接触槽内でオゾンと汚泥
が効率的に接触するため、汚泥の効果的なオゾン処理が
可能となり、汚泥の腐敗を防止することができる。In particular, since ozone and sludge come into efficient contact with each other in the downcomer pipe and the contact tank, the sludge can be effectively treated with ozone and spoilage can be prevented.
【００３８】[0038]
【発明の効果】以上説明した本発明にかかる汚泥処理方
法とその装置によれば、オゾン接触槽内に貯留された汚
泥を循環経路を経由して引き上げ、オゾンガスを吸引し
ながら反応管内を下降流として流れる際に、下降時の混
合作用によってオゾンガスと汚泥とが充分に接触し、且
つ汚泥とオゾンガスとの混合液がオゾン接触槽内の底壁
近傍まで深く潜入して汚泥の撹拌作用をもたらし、オゾ
ン接触反応を促進することができる。According to the sludge treatment method and the apparatus thereof according to the present invention described above, the sludge stored in the ozone contact tank is pulled up through the circulation path, and the sludge flows downward in the reaction tube while sucking the ozone gas. When flowing as, the ozone gas and the sludge are sufficiently contacted by the mixing action at the time of descending, and the mixed liquid of the sludge and the ozone gas deeply penetrates to the vicinity of the bottom wall in the ozone contact tank to bring about the stirring action of the sludge, The ozone contact reaction can be promoted.
【００３９】特に従来から知られているオゾン処理法と
して、オゾン接触槽の底壁近傍に多孔質体でなる散気管
を配置してオゾンガスを被処理水中に放散する通常の方
法に比較してもオゾン処理効率が格段に高くなり、しか
も対象となる被処理水に多量の汚泥粒子が含有されてい
る場合でも散気管における孔部の目詰まり等の難点は全
く生じないため、オゾン処理効率が径時的に劣化する虞
れはなく、散気管等の部品自体の交換は当然不要である
ため、メンテナンス性を高めるとともにコストの面でも
有利である。In particular, as a conventionally known ozone treatment method, a comparison is made with a usual method in which an air diffuser made of a porous material is arranged near the bottom wall of an ozone contact tank to diffuse ozone gas into the water to be treated. Ozone treatment efficiency is much higher, and even if the target water to be treated contains a large amount of sludge particles, there are no problems such as clogging of the holes in the air diffuser, so the ozone treatment efficiency is There is no risk of deterioration over time, and it is naturally unnecessary to replace the parts such as the air diffusing tube, which improves the maintainability and is advantageous in terms of cost.
【００４０】又、オゾン接触槽内の反応で消費されずに
残ったオゾンガスを排オゾンガスとして引き抜いて一部
を反応管に注入することにより、汚泥の自然流下流量と
循環汚泥の流量、発生オゾンガスとの流量のバランスが
良好になり、排オゾンガスの再利用に伴って効率的なオ
ゾンガスの利用が可能となる。Further, the ozone gas remaining without being consumed by the reaction in the ozone contact tank is extracted as exhaust ozone gas and a part thereof is injected into the reaction tube, whereby the natural flow rate of sludge and the flow rate of circulating sludge, and the generated ozone gas. The balance of the flow rates is improved, and the ozone gas can be used efficiently as the exhaust ozone gas is reused.
【００４１】更に反応管の形状をスパイラル型（渦流
状）もしくはジグザク構造にしたことにより、同じ高さ
の直管型反応管を流れるのと同じ流量での管の長さ、即
ち、気液接触時間を長くすることができて、オゾン接触
反応をより一層高めることができる。Further, by making the shape of the reaction tube a spiral type (vortex type) or a zigzag structure, the length of the tube at the same flow rate as flowing through a straight type reaction tube of the same height, that is, gas-liquid contact The time can be lengthened and the ozone contact reaction can be further enhanced.
【図１】本実施例にかかる下水汚泥の連続オゾン処理シ
ステムを全体的に示す概要図。FIG. 1 is a schematic view showing an overall continuous ozone treatment system for sewage sludge according to this embodiment.
【図２】本発明で採用したオゾン接触槽の実施例１を示
す要部詳細図。FIG. 2 is a detailed view of the essential parts showing Example 1 of the ozone contact tank adopted in the present invention.
【図３】オゾン接触槽の実施例２を示す要部詳細図。FIG. 3 is a detailed view of the essential parts showing the second embodiment of the ozone contact tank.
【図４】オゾン接触槽の実施例３を示す要部詳細図。FIG. 4 is a detailed view of the essential parts showing Example 3 of the ozone contact tank.
【図５】オゾン接触槽の実施例４を示す要部詳細図。FIG. 5 is a detailed view of essential parts showing an ozone contact tank according to a fourth embodiment.
【図６】従来の汚泥集約処理の各種方法を説明するため
の概要図。FIG. 6 is a schematic diagram for explaining various methods of conventional sludge aggregation processing.
１…汚泥流入渠 ２…水中ポンプ ３…汚泥中継槽 ４…撹拌機構 ５，１６…ｐＨ計 ６，１７…ＯＲＰ計（酸化還元電位計） ７…レベル計 ８…汚泥供給ポンプ ９…オゾン接触槽 １０…循環ポンプ １１…オゾン発生機 １２…反応管 １３は液位調整槽 １４…計測槽 １８…濃縮槽 １９…排オゾン処理施設 ２０…循環経路 ２１…返流水 ２２…濃縮汚泥 ２３…汚泥貯留槽 ２４…チューブ 1 ... Sludge inflow 2 ... Submersible pump 3 ... Sludge relay tank 4 ... Stirring mechanism 5, 16 ... pH meter 6, 17 ... ORP meter (oxidation-reduction potentiometer) 7… Level meter 8 ... Sludge supply pump 9 ... Ozone contact tank 10 ... Circulation pump 11 ... Ozone generator 12 ... Reaction tube 13 is a liquid level adjusting tank 14 ... Measuring tank 18 ... Concentration tank 19 ... Waste ozone treatment facility 20 ... Circulation path 21 ... Return water 22 ... Concentrated sludge 23 ... Sludge storage tank 24 ... tube
───────────────────────────────────────────────────── フロントページの続き (72)発明者 塚本 慶一 東京都品川区大崎２丁目１番17号 株式 会社明電舎内 (56)参考文献 特開 平８−192196（ＪＰ，Ａ) 特開 昭56−17625（ＪＰ，Ａ) 特開 平６−154796（ＪＰ，Ａ) 特開 平６−233989（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) C02F 11/00 - 11/20 C02F 1/78 B01F 1/00 - 5/26 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Keiichi Tsukamoto 2-1-117 Osaki, Shinagawa-ku, Tokyo Meidensha Co., Ltd. (56) References JP-A-8-192196 (JP, A) JP-A-56- 17625 (JP, A) JP-A-6-154796 (JP, A) JP-A-6-233989 (JP, A) (58) Fields investigated (Int.Cl. 7 , DB name) C02F 11/00-11 / 20 C02F 1/78 B01F 1/00-5/26
Claims (5)
して、オゾンガスを汚泥中に放散することによって殺
菌、脱臭及び脱色処理を行うようにした下水汚泥のオゾ
ン処理において、 上記オゾン接触槽の上部に、該オゾン接触槽の上壁を貫
通して嵌入されているとともに下端部をオゾン接触槽内
の汚泥水位に一致した状態として縦方向に固定された縦
型の反応管を設け、循環ポンプの駆動によってオゾン接
触槽内の汚泥を循環経路を介して該反応管の上方部に送
り込むと同時にオゾン発生機から得られるオゾンガスを
該反応管の上部から導入することにより、反応管内で汚
泥とオゾンとを下降流として接触反応させてオゾン接触
槽内に流入させるようにしたことを特徴とする下水汚泥
のオゾン処理方法。1. An ozone treatment of sewage sludge, wherein sewage sludge is sterilized, deodorized and decolorized by flowing ozone gas into the sludge so that ozone gas is diffused into the ozone contact tank. A vertical reaction tube is inserted into the upper part of the ozone contact tank through the upper wall of the ozone contact tank, and the lower end is vertically fixed with the sludge water level in the ozone contact tank aligned with the vertical reaction tube. The sludge in the ozone contact tank is sent to the upper part of the reaction tube through the circulation path by driving the pump, and at the same time, the ozone gas obtained from the ozone generator is introduced from the upper part of the reaction tube to remove sludge in the reaction tube. A method of ozone treatment of sewage sludge, characterized in that ozone is brought into contact with the ozone as a downward flow to cause a reaction to flow into the ozone contact tank.
設けて、オゾン接触槽内の汚泥を循環ポンプ及び循環経
路を介して上方に引き上げて汚泥貯留槽内に一旦流入さ
せた後、供給された汚泥をオゾンとともに反応管内を下
降流として自然落下させるようにした請求項１記載の下
水汚泥のオゾン処理方法。2. A sludge storage tank is provided above the vertical reaction tube, and sludge in the ozone contact tank is pulled upward through a circulation pump and a circulation path to once flow into the sludge storage tank. The ozone treatment method for sewage sludge according to claim 1, wherein the supplied sludge is allowed to naturally fall together with ozone as a downward flow in the reaction tube.
に残ったオゾンガスを排オゾンガスとして引き抜き、そ
の一部を反応管に注入オゾンガスとともに注入するよう
にした請求項１，２記載の下水汚泥のオゾン処理方法。3. The sewage sludge according to claim 1, wherein the ozone gas remaining without being consumed by the reaction in the ozone contact tank is extracted as exhaust ozone gas, and a part of the ozone gas is injected into the reaction tube together with the ozone gas. Ozone treatment method.
型（渦流状）もしくはジグザク構造とした請求項１，
２，３記載の下水汚泥のオゾン処理方法。4. The vertical reaction tube has a spiral (vortex) or zigzag structure.
A method for ozone treatment of sewage sludge according to a few items.
して、オゾンガスを汚泥中に放散することによって殺
菌、脱臭及び脱色処理を行うようにした下水汚泥のオゾ
ン処理において、 上記オゾン接触槽の上部にあって、該オゾン接触槽の上
壁を貫通して嵌入されているとともに下端部がオゾン接
触槽内の汚泥水位に一致した状態として固定された縦型
の反応管と、オゾン接触槽内の汚泥を該反応管の上方部
に送り込む循環経路及び循環ポンプと、オゾン発生機か
ら得られるオゾンガスを該反応管の上部から反応管内に
送り込む導入機構とを具備してなり、反応管内で汚泥と
オゾンとを下降流として接触反応させてオゾン接触槽内
に流入させるようにしたことを特徴とする下水汚泥のオ
ゾン処理装置。5. The ozone treatment of sewage sludge, wherein sewage sludge is flown into a closed ozone contact tank to disinfect ozone gas into the sludge for sterilization, deodorization and decolorization. A vertical reaction tube that is fitted in the upper part of the ozone contact tank through the upper wall of the ozone contact tank and has its lower end fixed so as to match the sludge water level in the ozone contact tank; The sludge in the reaction tube is provided with a circulation path and a circulation pump for sending the sludge inside the reaction tube to the upper part of the reaction tube, and an introduction mechanism for sending the ozone gas obtained from the ozone generator into the reaction tube from the upper part of the reaction tube. An ozone treatment apparatus for sewage sludge, characterized in that the ozone and ozone are brought into contact with each other as a downward flow to flow into the ozone contact tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15887795A JP3446401B2 (en) | 1995-06-26 | 1995-06-26 | Ozone treatment method and treatment device for sewage sludge |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15887795A JP3446401B2 (en) | 1995-06-26 | 1995-06-26 | Ozone treatment method and treatment device for sewage sludge |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH091196A JPH091196A (en) | 1997-01-07 |
| JP3446401B2 true JP3446401B2 (en) | 2003-09-16 |
Family
ID=15681354
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15887795A Expired - Fee Related JP3446401B2 (en) | 1995-06-26 | 1995-06-26 | Ozone treatment method and treatment device for sewage sludge |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3446401B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4851965B2 (en) * | 2007-03-06 | 2012-01-11 | 三菱電機株式会社 | Sludge treatment equipment |
| CN108395069B (en) * | 2018-03-30 | 2020-02-21 | 江苏大学 | Sludge reduction device for urban sewage treatment plant |
-
1995
- 1995-06-26 JP JP15887795A patent/JP3446401B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH091196A (en) | 1997-01-07 |
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