JP5377413B2

JP5377413B2 - Detoxification method for PCB mixed insulating oil

Info

Publication number: JP5377413B2
Application number: JP2010129602A
Authority: JP
Inventors: 賢治徳政
Original assignee: Chugoku Electric Power Co Inc
Current assignee: Chugoku Electric Power Co Inc
Priority date: 2010-06-07
Filing date: 2010-06-07
Publication date: 2013-12-25
Anticipated expiration: 2030-06-07
Also published as: JP2011254868A

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of de-toxifying PCB mixed-in insulating oil, preventing trouble or bad influence caused by the PCB mixed-in insulating oil containing impurity to stably de-toxify the PCB mixed-in insulating oil. <P>SOLUTION: According to the method of de-toxifying the PCB mixed-in insulating oil, the PCB mixed-in insulating oil containing impurity is taken as oil to be processed, and after water contained in the oil to be processed is removed, metallic sodium and PCB are caused to react with each other to thereby de-toxify the oil to be processed. The impurity is oxidized alteration oil, and one or more selected from a metal oxide, a metal hydroxide and carbonate are added to the oil to be processed before removing water contained therein at the latest. <P>COPYRIGHT: (C)2012,JPO&INPIT

Description

本発明は、不純物を含むＰＣＢ混入絶縁油を無害化するＰＣＢ混入絶縁油の無害化処理方法に関する。 The present invention relates to the detoxification how the PCB contamination insulating oil detoxifies PCB contamination insulating oil containing impurities.

ＰＣＢ（ポリ塩化ビフェニル）は、不燃性で化学安定性及び電気絶縁性に優れるため、従来、電気機器の絶縁油などとして使用されていたが、その有害性から現在では使用が禁止され、保管されているＰＣＢ及びＰＣＢを含有する廃油などについても、平成１３年に制定された「ポリ塩化ビフェニル廃棄物の適正な処理の推進に関する特別措置法（ＰＣＢ特措法）」により、平成２８年７月までに処理を完了することが義務付けられている。 PCB (polychlorinated biphenyl) is nonflammable and excellent in chemical stability and electrical insulation, so it was conventionally used as an insulating oil for electrical equipment, but its use is now prohibited and stored due to its harmfulness. PCBs and waste oils containing PCBs, etc., by July 2016, according to the “Special Measures Law for Promotion of Proper Treatment of Polychlorinated Biphenyl Waste (PCB Special Measures Law)” enacted in 2001 Completion of processing is required.

ＰＣＢの脱塩素化技術は、これまでに多くの方法が提案されており、幾つかの方法は実用化されている。金属ナトリウムとＰＣＢとを反応させＰＣＢを脱塩素化させる方法は、ＰＣＢ混入絶縁油の無害化処理に使用され、処理プラントも稼働中である。金属ナトリウムとＰＣＢとを反応させるとＰＣＢが脱塩素化され、ビフェニル、塩化ナトリウム、ビフェニルが重合したビフェニル重合物、水酸化ナトリウムが生成するが、この生成物に関しては幾つかの問題が指摘され、これに対する対策案が提案されている（例えば特許文献１参照）。 Many methods have been proposed for PCB dechlorination techniques, and several methods have been put to practical use. The method of dechlorinating PCB by reacting sodium metal with PCB is used for detoxification treatment of PCB mixed insulating oil, and the processing plant is also in operation. When metal sodium and PCB are reacted, PCB is dechlorinated to produce biphenyl, sodium chloride, a biphenyl polymer obtained by polymerizing biphenyl, and sodium hydroxide. Several problems have been pointed out regarding this product, A countermeasure for this has been proposed (see, for example, Patent Document 1).

また不純物を含むＰＣＢ混入絶縁油を処理すると処理設備、処理プロセスに悪影響を及ぼす。例えば、ＰＣＢ混入絶縁油を抜き出した後に柱上変圧器を破砕しこれを真空加熱し回収される留出液には水溶性の有機酸が含まれ、これが配管を腐食させることがある。またＰＣＢと金属ナトリウムとを反応させるに先立ち行なわれる被処理油中の水分除去操作により、タール状のスラッジが析出し、これがストレーナを閉塞させることがある。これに対し本出願人は、既に有機酸を除去する装置を開発し特許出願中である（特願２００８−３１８１１４）。またＰＣＢ汚染物を真空加熱し回収される回収物には、ＰＣＢを含む炭化水素系油状物の他、熱分解生成物である木酢液、タール状物質が含まれ、これらがＰＣＢの分解処理に悪影響を及ぼすとし、ＰＣＢの分解処理に先立ち、蒸留操作により低沸点熱分解生成物を除去し、さらに吸着剤を使用しタール状物質を吸着除去する技術が提案されている（例えば特許文献２参照）。 Moreover, if the PCB mixed insulating oil containing impurities is treated, the treatment equipment and the treatment process are adversely affected. For example, a distillate collected by extracting a PCB-mixed insulating oil after crushing a pole transformer and heating it in a vacuum contains water-soluble organic acid, which may corrode piping. Moreover, tar-like sludge may be deposited by the water removal operation in the oil to be treated prior to the reaction between PCB and metallic sodium, which may block the strainer. On the other hand, the present applicant has already developed a device for removing an organic acid and has applied for a patent (Japanese Patent Application No. 2008-318114). In addition to the hydrocarbon-based oils containing PCB, the recovered materials collected by vacuum heating of PCB contaminants include pyrolysis products, such as pyroligneous acid and tar-like substances, which are used for PCB decomposition. A technique has been proposed in which a low boiling point pyrolysis product is removed by a distillation operation prior to PCB decomposition, and a tar-like substance is adsorbed and removed using an adsorbent (see, for example, Patent Document 2). ).

特開２００５−３１９４１５号公報JP 2005-319415 A 特開２００４−１７４２９４号公報JP 2004-174294 A

上記以外に不純物を含むＰＣＢ混入絶縁油を金属ナトリウムで無害化処理すると、反応槽内にスケールが析出し、これが剥離し配管を閉塞させる、さらには金属ナトリウムの消費量が多くなる等の問題が発生する。以上のように不純物を含むＰＣＢ混入絶縁油を無害化処理するとき、無害化処理設備、運転に多くのトラブル又は悪影響が発生するが、これまでこのような問題点は指摘されておらず、これらを効果的に防止する方法の開発が待たれている。 In addition to the above, if PCB-containing insulating oil containing impurities is detoxified with metallic sodium, scale precipitates in the reaction tank, which peels off and closes the piping, and further increases the consumption of metallic sodium. Occur. As described above, when PCB-insulated insulating oil containing impurities is detoxified, many troubles or adverse effects occur in the detoxification equipment and operation, but such problems have not been pointed out so far. The development of a method to effectively prevent this is awaited.

本発明の目的は、不純物を含むＰＣＢ混入絶縁油が引き起こすトラブル又は悪影響を防止し安定的にＰＣＢを無害化処理することができるＰＣＢ混入絶縁油の無害化処理方法を提供することである。 An object of the present invention is to provide a method for detoxifying PCB-containing insulating oil that can prevent troubles or adverse effects caused by PCB-containing insulating oil containing impurities and stably detoxify PCB .

本発明者らは、鋭意検討を重ねた結果、ＰＣＢ混入絶縁油の無害化処理、貯蔵において、不純物を含むＰＣＢ混入絶縁油を被処理油とするとき発生する種々のトラブル、悪影響は、被処理油に含まれる酸化変質油に起因し、さらに酸化変質油の特性を抑え込むことでトラブル、悪影響を抑制することができることを見出し、本発明を完成するに至った。 As a result of intensive studies, the present inventors have made various troubles and adverse effects that occur when the PCB-containing insulating oil containing impurities is treated in the detoxification treatment and storage of PCB-containing insulating oil. The present inventors have found that troubles and adverse effects can be suppressed by suppressing the properties of the oxidized modified oil due to the oxidized modified oil contained in the oil, and the present invention has been completed.

すなわち本発明は、不純物を含むＰＣＢ混入絶縁油を被処理油とし、該被処理油に含まれる水分を除去した後に金属ナトリウムとＰＣＢとを反応させ被処理油を無害化するＰＣＢ混入絶縁油の無害化処理方法において、前記被処理油が紙木類乾留物を含むＰＣＢ混入絶縁油で、不純物が酸化変質油であり、遅くとも被処理油に含まれる水分を除去する前までに、前記被処理油に金属酸化物、金属水酸化物及び炭酸塩のうち１種以上を添加することを特徴とするＰＣＢ混入絶縁油の無害化処理方法である。 That is, the present invention relates to a PCB-mixed insulating oil that uses a PCB-mixed insulating oil containing impurities as a treated oil, and after removing moisture contained in the treated oil, reacts sodium metal and PCB to render the treated oil harmless. In the detoxification treatment method, the treated oil is a PCB mixed insulating oil containing a paper-wood dry matter, the impurity is an oxidized denatured oil, and before the moisture contained in the treated oil is removed at the latest. A method for detoxifying PCB-containing insulating oil, wherein one or more of metal oxide, metal hydroxide, and carbonate are added to oil.

また本発明において、前記酸化変質油は、Ｃ＝Ｏ結合及びＣ−Ｏ結合を含むことを特徴とする。 In the present invention, the oxidized modified oil includes a C═O bond and a C—O bond.

また本発明において、前記金属酸化物、金属水酸化物及び炭酸塩が、アルカリ金属、アルカリ土類金属、アルミニウムの酸化物、水酸化物及び炭酸塩であることを特徴とする。 In the present invention, the metal oxide, metal hydroxide and carbonate are alkali metal, alkaline earth metal, aluminum oxide, hydroxide and carbonate.

また本発明において、前記被処理油は、少なくともＰＣＢ汚染物を真空加熱し回収される回収絶縁油を含み、前記紙木類乾留物は前記回収絶縁油に含まれることを特徴とする。 In the present invention, the oil to be treated includes at least a recovered insulating oil that is recovered by vacuum-heating PCB contaminants, and the paper-wood dry distillate is included in the recovered insulating oil.

また本発明において、ＰＣＢと金属ナトリウムとを反応させるに先立ち、前記金属酸化物、金属水酸化物及び炭酸塩のうち１種以上が添加された被処理油を加熱及び減圧し、添加された前記金属酸化物、金属水酸化物及び炭酸塩のうち１種以上と前記酸化変質油とを反応させることを特徴とする。 In the present invention, prior to the reaction of PCB and metal sodium, the metal oxide, the treated oil which one or more of the metal hydroxides and carbonates are added heating and under reduced pressure, were added the One or more of metal oxides, metal hydroxides and carbonates are reacted with the oxidized modified oil.

また本発明において、ＰＣＢ汚染物を真空加熱し回収する回収絶縁油を貯蔵する回収油貯蔵タンクと、前記回収油貯蔵タンクに貯蔵する回収絶縁油を輸送するタンクローリーと、前記タンクローリーから払出される回収絶縁油を含むＰＣＢ混入絶縁油を貯蔵する処理タンクと、前記処理タンクから払出される被処理油を受入れ被処理油から水分を除去する減圧蒸留槽と、水分が除去された被処理油を金属ナトリウムで無害化する反応槽とを備えるＰＣＢ混入絶縁油無害化処理設備を用いＰＣＢ混入絶縁油を無害化処理するとき、前記回収油貯蔵タンク、前記タンクローリー、前記タンクローリーと前記処理タンクとを結ぶ払出しライン、前記処理タンク及び前記処理タンクと前記減圧蒸留槽とを結ぶ払出しラインのうち少なくともいずれか１の場所で、遅くとも被処理油に含まれる水分を除去する前までに前記金属酸化物、金属水酸化物及び炭酸塩のうち１種以上を添加することを特徴とする。 In the present invention, the recovered oil storage tank for storing the recovered insulating oil for recovering the PCB contaminants by vacuum heating, the tank lorry for transporting the recovered insulating oil stored in the recovered oil storage tank, and the recovery discharged from the tank lorry A processing tank for storing insulating oil containing PCB containing insulating oil, a vacuum distillation tank for receiving the oil to be processed discharged from the processing tank and removing water from the oil to be processed, and a metal to be processed from which water has been removed Discharge of connecting the recovered oil storage tank, the tank lorry, the tank lorry and the processing tank when detoxifying the PCB mixed insulating oil using a PCB-containing insulating oil detoxifying treatment facility comprising a reaction tank detoxified with sodium At least one of a line, the processing tank, and a discharge line connecting the processing tank and the vacuum distillation tank In place, the metal oxide at the latest before removing the moisture contained in the treated oil, characterized by adding one or more of the metal hydroxides and carbonates.

また本発明において、前記金属酸化物、金属水酸化物及び炭酸塩のうち１種以上の添加が、前記回収油貯蔵タンク、前記タンクローリー、前記タンクローリーと前記処理タンクとを結ぶ払出しライン及び前記処理タンクのうち少なくともいずれか１の場所で、遅くとも被処理油に含まれる水分を除去する前までに水酸化マグネシウムを添加することであり、かつ前記処理タンク及び前記処理タンクと前記減圧蒸留槽とを結ぶ払出しラインのうち少なくともいずれか１の場所で、遅くとも被処理油に含まれる水分を除去する前までにナトリウム及び／又はカリウムの酸化物及び／又は水酸化物を添加することであることを特徴とする。 Further, in the present invention, one or more of the metal oxide, metal hydroxide and carbonate are added to the recovered oil storage tank, the tank lorry, a discharge line connecting the tank lorry and the processing tank, and the processing tank. And adding magnesium hydroxide before removing the water contained in the oil to be treated at least at any one of the locations, and connecting the treatment tank and the treatment tank to the vacuum distillation tank at least any one of location of the dispensing line, and characterized in that the addition of oxides and / or hydroxides of sodium and / or potassium and before removing the latest moisture contained in the treated oil To do.

また本発明において、前記ナトリウム及び／又はカリウムの酸化物及び／又は水酸化物の添加と共に、前記処理タンク及び前記処理タンクと前記減圧蒸留槽とを結ぶ払出しラインのうち少なくともいずれか１の場所で、遅くとも被処理油に含まれる水分を除去する前までにナトリウム及び／又はカリウムの炭酸塩を添加することを特徴とする。 In the present invention, at least one of the treatment tank and the discharge line connecting the treatment tank and the vacuum distillation tank together with the addition of the sodium and / or potassium oxide and / or hydroxide. Further, it is characterized in that sodium and / or potassium carbonate is added at the latest before removing water contained in the oil to be treated .

本発明に係るＰＣＢ混入絶縁油の無害化処理方法は、酸化変質油を含むＰＣＢ混入絶縁油を被処理油とするとき、遅くとも被処理油に含まれる水分を除去する前までに、被処理油に金属酸化物、金属水酸化物及び炭酸塩のうち１種以上を添加することで、酸化変質油がスラッジ化することを防止し、又はスラッジとなった酸化変質油を分散させ、又は酸化変質油中の酸性成分を中和させる。これにより酸化変質油を含むＰＣＢ混入絶縁油が引き起こすトラブルを防止し安定的にＰＣＢを無害化処理することができる。また酸化変質油と添加した金属酸化物、金属水酸化物、炭酸塩とを反応させることで、酸化変質油が金属ナトリウムと反応することを防止することができ、金属ナトリウムの使用量を低減し、さらにスケールの発生を抑制することができる。 The detoxifying treatment method for PCB-mixed insulating oil according to the present invention uses the PCB-mixed insulating oil containing oxidized and denatured oil as the oil to be treated before the moisture contained in the oil to be treated is removed at the latest. By adding one or more of metal oxides, metal hydroxides and carbonates, it is possible to prevent oxidation-modified oil from becoming sludge, or to disperse oxidation-modified oil that has become sludge, Neutralizes acidic components in oil. As a result, troubles caused by the PCB mixed insulating oil containing the oxidized denatured oil can be prevented, and the PCB can be stably rendered harmless. In addition, by reacting oxidized modified oil with added metal oxides, metal hydroxides, and carbonates, it is possible to prevent oxidized modified oil from reacting with metallic sodium, reducing the amount of metallic sodium used. Further, the generation of scale can be suppressed .

本発明に係るＰＣＢ混入絶縁油の無害化処理方法を適用するＰＣＢ混入絶縁油無害化処理設備１の概略的構成を示す図である。It is a figure which shows schematic structure of the PCB mixing insulating oil detoxification processing equipment 1 which applies the detoxification processing method of the PCB mixing insulating oil which concerns on this invention. 紙木類乾留物を含む絶縁油と紙木類乾留物を含まない絶縁油をフーリエ変換赤外分光法ＦＴＩＲで分析した結果を示す図である。It is a figure which shows the result of having analyzed the insulating oil containing paper wood dry matter and the insulating oil which does not contain paper wood dry matter by Fourier-transform infrared spectroscopy FTIR. 被処理油にＮａＯＨ又はＭｇ（ＯＨ）_２を添加したときの反応槽２５に添加する金属ナトリウム注入量と反応後の処理済油中のＰＣＢ濃度の関係を示す図である。It is a figure which shows the relationship between the metal sodium injection amount added to the reaction tank 25 when adding NaOH or Mg (OH) ₂ to to-be-processed oil, and the PCB density | concentration in the processed oil after reaction.

本発明に係るＰＣＢ混入絶縁油の無害化処理方法は、酸化変質油を含むＰＣＢ混入絶縁油を被処理油とし、該被処理油に含まれる水分を除去した後に金属ナトリウムとＰＣＢとを反応させ被処理油を無害化するとき、遅くとも被処理油に含まれる水分を除去する前までに、被処理油に金属酸化物、金属水酸化物及び炭酸塩のうち１種以上を添加することを特徴とする。本発明に係るＰＣＢ混入絶縁油の無害化処理方法は、図１に示すＰＣＢ混入絶縁油無害化処理設備１に適用することができる。まずＰＣＢ混入絶縁油無害化処理設備１の構成及びプロセス、さらには酸化変質油が引き起こすトラブル、悪影響について説明し、続いて金属酸化物、金属水酸化物及び炭酸塩の添加要領、作用効果について説明する。 The detoxifying treatment method for PCB-mixed insulating oil according to the present invention uses PCB-mixed insulating oil containing oxidized and denatured oil as the oil to be treated, and after removing water contained in the oil to be treated, reacts sodium metal and PCB. When detoxifying the oil to be treated, it is characterized by adding at least one of metal oxide, metal hydroxide and carbonate to the oil to be treated before removing the water contained in the oil to be treated at the latest. And The PCB-mixed insulating oil detoxifying treatment method according to the present invention can be applied to the PCB-mixed insulating oil detoxifying treatment facility 1 shown in FIG. First, the configuration and process of the PCB-mixed insulating oil detoxification treatment facility 1 and the troubles and adverse effects caused by the oxidized and denatured oil will be explained, followed by the addition procedure and effects of metal oxides, metal hydroxides and carbonates. To do.

ＰＣＢ混入絶縁油無害化処理設備１は、ＰＣＢ混入絶縁油、さらにはＰＣＢ汚染物に付着するＰＣＢ混入絶縁油を回収し、これらを金属ナトリウムで無害化する設備であり、ＰＣＢ汚染物を真空加熱し汚染物に付着する絶縁油を回収する絶縁油回収装置２と、絶縁油回収装置２で回収される回収絶縁油及び柱上変圧器から抜き出されたＰＣＢ混入絶縁油等を無害化する無害化処理装置３とに大別される。以下、柱上変圧器に充填されたＰＣＢ微量混入絶縁油及び柱上変圧器に付着するＰＣＢ微量混入絶縁油を回収し、これらを無害化処理する場合を例に取り説明する。 The PCB-mixed insulating oil detoxification treatment facility 1 is a facility that collects PCB-mixed insulating oil and further PCB-mixed insulating oil adhering to PCB contaminants and detoxifies them with metal sodium. Insulating oil recovery device 2 that recovers the insulating oil adhering to the contaminants, harmlessness that makes the insulating oil recovered by the insulating oil recovery device 2 and PCB mixed insulating oil extracted from the pole transformer harmless It is divided roughly into the chemical processing apparatus 3. Hereinafter, the case where the PCB trace mixed insulating oil filled in the pole transformer and the PCB trace mixed insulating oil adhering to the pole transformer are collected and detoxified will be described as an example.

絶縁油回収装置２は、ＰＣＢ汚染物を真空加熱し汚染物に付着する絶縁油を回収する装置であり、ＰＣＢ汚染物を真空加熱する真空加熱炉１１、真空加熱炉１１で蒸発させた絶縁油等を凝縮させる凝縮器１３、凝縮器１３で凝縮回収した凝縮液に含まれる水を分離する油水分離器１５及び回収絶縁油を貯蔵する回収油貯蔵タンク１７を含む。 The insulating oil recovery device 2 is a device that recovers the insulating oil attached to the contaminant by vacuum heating the PCB contaminant. The insulating oil evaporated in the vacuum heating furnace 11 and the vacuum heating furnace 11 that vacuum heats the PCB contaminant. The condenser 13 which condenses etc., the oil-water separator 15 which isolate | separates the water contained in the condensate condensed and collect | recovered with the condenser 13, and the collection | recovery oil storage tank 17 which stores collection | recovery insulating oil are included.

ＰＣＢ汚染物である柱上変圧器は、ＰＣＢ微量混入絶縁油を抜き出した後、解体、破砕されケース、銅線、金具、碍子、紙木などに分けられた後、各々真空加熱炉１１に投入される。真空加熱炉１１内は加熱され、さらに真空ポンプを含む減圧装置により減圧状態となっている。ケース等に付着するＰＣＢを含む絶縁油は、真空加熱炉１１内で蒸発し、凝縮器１３で冷却され凝縮した後、油水分離器１５に送られる。柱上変圧器は、銅線、金具などの金属のほか紙木を含むため、真空加熱炉１１で加熱されるとＰＣＢを含む絶縁油のほか、紙木が乾留されこれらが凝縮液となって油水分離器１５に送られる。このため凝縮液には、ＰＣＢを含む絶縁油のほか水、紙木類乾留物を含む。油水分離器１５では凝縮液が静置され比重差により油相と水相とに分離され、油相は、回収絶縁油として回収油貯蔵タンク１７に送られる。なお回収絶縁油にはＰＣＢを含む絶縁油の他、紙木類乾留物及び少量の水が含まれる。回収油貯蔵タンク１７の回収絶縁油は、タンクローリー１９で無害化装置３の処理タンク２１に送られる。 The pole transformer, which is a PCB contaminant, is extracted from PCB insulating oil, disassembled, crushed and separated into cases, copper wires, metal fittings, insulators, paper trees, etc., and then put into the vacuum heating furnace 11 Is done. The inside of the vacuum heating furnace 11 is heated and is in a reduced pressure state by a decompression device including a vacuum pump. The insulating oil containing PCB adhering to the case or the like is evaporated in the vacuum heating furnace 11, cooled and condensed by the condenser 13, and then sent to the oil / water separator 15. Since the pole transformer includes paper, in addition to metal such as copper wire and metal fittings, when heated in the vacuum heating furnace 11, the paper is dry-distilled in addition to insulating oil containing PCB, and these become condensate. It is sent to the oil / water separator 15. For this reason, the condensate contains water and paper wood distillate in addition to insulating oil containing PCB. In the oil / water separator 15, the condensate is allowed to stand and is separated into an oil phase and an aqueous phase due to a difference in specific gravity, and the oil phase is sent to the recovered oil storage tank 17 as recovered insulating oil. In addition, the recovered insulating oil includes paper and wood distillate and a small amount of water in addition to the insulating oil containing PCB. The recovered insulating oil in the recovered oil storage tank 17 is sent to the processing tank 21 of the detoxifying device 3 by the tank lorry 19.

無害化処理装置３は、ＳＰプロセス（soduim pulverulent dispersion）法を用いてＰＣＢ混入絶縁油を無害化する設備であり、金属ナトリウムとＰＣＢとを反応させＰＣＢを脱塩素化する。無害化処理装置３は、被処理油を貯蔵する処理タンク２１、被処理油に含まれる水を除去する減圧蒸留槽２３、ＰＣＢを金属ナトリウムと反応させ脱塩素化する反応槽２５、ＰＣＢの脱塩素化を確認するための分解確認槽２７、処理済油に含まれる残存金属ナトリウムを水和させ、さらに中和する抽出中和槽３１、処理済油と水とを分離する油水分離槽３３、水を回収する洗浄水再生設備３５を備える。 The detoxification treatment apparatus 3 is a facility for detoxifying PCB-containing insulating oil using an SP process (soduim pulverulent dispersion) method, and reacts metal sodium with PCB to dechlorinate PCB. The detoxification treatment apparatus 3 includes a treatment tank 21 for storing the oil to be treated, a vacuum distillation tank 23 for removing water contained in the oil to be treated, a reaction tank 25 for reacting the PCB with metal sodium and dechlorinating, and a removal of the PCB. Decomposition confirmation tank 27 for confirming chlorination, extraction neutralization tank 31 for hydrating and neutralizing residual metallic sodium contained in the treated oil, oil / water separation tank 33 for separating the treated oil and water, A washing water recycling facility 35 for collecting water is provided.

被処理油は、柱上変圧器から抜き出されたＰＣＢ微量混入絶縁油、又は柱上変圧器から抜き出されたＰＣＢ微量混入絶縁油と絶縁油回収装置２で回収される回収絶縁油との混合物であり、これらは処理タンク２１に貯蔵された後、減圧蒸留槽２３に送られる。 The to-be-treated oil is composed of the PCB trace mixed insulating oil extracted from the pole transformer, or the PCB trace mixed insulating oil extracted from the pole transformer and the recovered insulating oil recovered by the insulating oil recovery device 2. The mixture is stored in the processing tank 21 and then sent to the vacuum distillation tank 23.

減圧蒸留槽２３は、ジャケット付き攪拌槽であり、ジャケットに加熱した熱媒を供給することで被処理油を加熱する。また減圧蒸留槽２３は、槽内を減圧し被処理油に含まれる水を蒸発させ凝縮し回収する減圧装置（図示を省略）を備え、処理タンク２１から送られた被処理油は、ここで９０℃程度に加熱、０．０１４２Ｍｐａ程度に減圧され、被処理油に含まれる水が除去される。減圧蒸留槽２３で水分が除去された被処理油は反応槽２５に送られる。 The vacuum distillation tank 23 is a jacketed stirring tank, and heats the oil to be treated by supplying a heated heat medium to the jacket. The vacuum distillation tank 23 is equipped with a decompression device (not shown) that depressurizes the inside of the tank and evaporates, condenses, and recovers water contained in the oil to be treated, and the oil to be treated sent from the treatment tank 21 is here. It is heated to about 90 ° C. and depressurized to about 0.0142 Mpa to remove water contained in the oil to be treated. The treated oil from which moisture has been removed in the vacuum distillation tank 23 is sent to the reaction tank 25.

反応槽２５は、ジャケット付き攪拌槽であり、ここで減圧蒸留槽２３で水分が除去された被処理油に金属ナトリウムが添加される。金属ナトリウムは、絶縁油中に金属ナトリウムの微粒子を分散させた金属ナトリウム分散体（ＳＤ：soduim dispersion）として反応槽２５に添加される。被処理油と金属ナトリウムとは、攪拌されながらジャケットに供給される加熱した熱媒により９０℃程度まで加熱され、ＰＣＢは金属ナトリウムと反応し脱塩素化し、被処理油は無害化される。なお、金属ナトリウム分散体を添加し所定の時間経過後に、反応促進剤として所定量の水が添加される。反応槽２５の気相部には窒素ガスが供給されている。 The reaction tank 25 is a jacketed stirring tank, in which metal sodium is added to the oil to be treated from which water has been removed in the vacuum distillation tank 23. The metallic sodium is added to the reaction vessel 25 as a metallic sodium dispersion (SD: soduim dispersion) in which fine particles of metallic sodium are dispersed in insulating oil. The oil to be treated and the metal sodium are heated to about 90 ° C. by a heated heating medium supplied to the jacket while being stirred, and the PCB reacts with the metal sodium to dechlorinate, so that the oil to be treated is rendered harmless. A predetermined amount of water is added as a reaction accelerator after the metal sodium dispersion is added and a predetermined time elapses. Nitrogen gas is supplied to the gas phase portion of the reaction tank 25.

反応槽２５でＰＣＢが脱塩素化された被処理油（処理済油）は、分解確認槽２７に送られ、サンプリングライン２９を介してサンプリングされ、処理済油中のＰＣＢ濃度が所定の濃度以下になっているか確認される。ここでＰＣＢが所定濃度以下に達していないことが確認されると、処理済液を反応槽２５に返送し再度、ＰＣＢの脱塩素化を行う。処理済油は、ＰＣＢ濃度が所定の濃度以下であることが確認されると冷却され、その後に抽出中和槽３１に送られる。 The treated oil (treated oil) from which PCB has been dechlorinated in the reaction tank 25 is sent to the decomposition confirmation tank 27 and sampled through the sampling line 29, and the PCB concentration in the treated oil is below a predetermined concentration. Is confirmed. Here, when it is confirmed that the PCB does not reach the predetermined concentration or less, the treated liquid is returned to the reaction tank 25 and the PCB is dechlorinated again. The treated oil is cooled when it is confirmed that the PCB concentration is equal to or lower than a predetermined concentration, and then sent to the extraction neutralization tank 31.

分解確認槽２７から送られる処理済油は、抽出中和槽３１で多量の水と混合され、処理済油中に残存する金属ナトリウムが水和される。さらに金属ナトリウムが水和され生成した水酸化ナトリウムを中和させるための炭酸ガスが吹き込まれ所定のｐＨに調整された後、油水分離槽３３に送られる。 The treated oil sent from the decomposition confirmation tank 27 is mixed with a large amount of water in the extraction neutralization tank 31, and the metallic sodium remaining in the treated oil is hydrated. Further, carbon dioxide gas for neutralizing sodium hydroxide produced by hydration of metallic sodium is blown and adjusted to a predetermined pH, and then sent to the oil / water separation tank 33.

油水分離槽３３に送られる多量の水を含む処理済油は、油水分離槽３３で静置され比重差により油相３７と水相３９とに分離される。上層の油相３７は、処理済油タンク４１に送られ貯蔵される。一方、下層の水相３９は、水を回収する洗浄水再生設備３５に送られる。 The treated oil containing a large amount of water sent to the oil / water separation tank 33 is left in the oil / water separation tank 33 and separated into an oil phase 37 and an aqueous phase 39 due to a difference in specific gravity. The upper oil phase 37 is sent to the treated oil tank 41 and stored. On the other hand, the lower aqueous phase 39 is sent to a washing water recycling facility 35 that collects water.

洗浄水再生設備３５は、乾燥機４３を備え、水を蒸発させ回収すると共に水に含まれる塩化ナトリウム等を蒸発乾固させる。油水分離槽３３から送られる水は静置分離水受槽４５に一度、貯留された後、乾燥機４３に送られ加熱される。蒸発した水は、凝縮器４７で凝縮し凝縮水槽４９に貯留される。この水は抽出中和槽３１に送られ、金属ナトリウムを水和させるための水として使用される。一方、水に溶解していた塩化ナトリウム等は乾燥汚泥として回収される。このように無害化処理装置３は、水を系外に排出しないクローズドシステムとなっている。 The washing water regeneration facility 35 includes a dryer 43, which evaporates and collects water and evaporates and drys sodium chloride contained in the water. The water sent from the oil / water separation tank 33 is once stored in the stationary separation water receiving tank 45 and then sent to the dryer 43 and heated. The evaporated water is condensed by the condenser 47 and stored in the condensed water tank 49. This water is sent to the extraction neutralization tank 31 and used as water for hydrating metallic sodium. On the other hand, sodium chloride or the like dissolved in water is recovered as dry sludge. In this way, the detoxification processing device 3 is a closed system that does not discharge water out of the system.

ＰＣＢ微量混入絶縁油を抜き出した後の柱上変圧器を破砕しこれを真空加熱し回収される回収絶縁油が含まれるＰＣＢ微量混入絶縁油を被処理油とする場合、被処理油には、Ｃ＝Ｏ結合及びＣ−Ｏ結合を含む酸化変質油が含まれる。Ｃ＝Ｏ結合及びＣ−Ｏ結合を含む酸化変質油が含まれるのは、柱上変圧器に紙、木が含まれ、これらの乾留物が回収絶縁油に含まれることによる。図２は、紙木類乾留物を含む絶縁油と紙木類乾留物を含まない絶縁油をフーリエ変換赤外分光法ＦＴＩＲで分析した結果を示す図である。紙木類乾留物を含む絶縁油にはＣ＝Ｏのピーク１７５０ｃｍ^−１が強く表れている。Ｃ＝Ｏ結合を含む酸化変質油としては、カルボン酸、エステル、アルデヒド、ケトンがある。酸化変質油はカルボン酸、アルコール類など水溶性の酸化変質油、非水溶性の酸化変質油を含み、極性が強いため、一部の酸化変質油は時間経過と共に酸化変質油同士が凝集、合体しスラッジとなり析出する。 When the PCB transformer mixed oil containing the recovered insulating oil is recovered by crushing the pole transformer after extracting the PCB trace insulating oil and vacuum heating it, Oxidized modified oils containing C═O bonds and C—O bonds are included. The reason why the oxidized modified oil containing C═O bond and C—O bond is included is that the pole transformer includes paper and wood, and these dry-distilled products are included in the recovered insulating oil. FIG. 2 is a diagram showing the results of analysis by Fourier transform infrared spectroscopy FTIR of insulating oil containing paper-wood dry matter and insulating oil not containing paper-wood dry matter. A peak of 1750 cm ^{−1 of} C═O appears strongly in the insulating oil containing the paper tree dry matter. Examples of the oxidized modified oil containing a C═O bond include carboxylic acid, ester, aldehyde, and ketone. Oxidized and modified oils include water-soluble oxidized and modified oils such as carboxylic acids and alcohols, and water-insoluble oxidized and modified oils. Because of their strong polarity, some oxidized and modified oils aggregate and coalesce with each other over time. Sludge becomes sludge and precipitates.

上記ＰＣＢ混入絶縁油無害化処理設備１を用いて酸化変質油を含むＰＣＢ混入絶縁油を処理する場合、析出するスラッジはタール状で粘性が高いため、例えば回収油貯蔵タンク１７から回収絶縁油を払出すラインに設けられたストレーナ（図示を省略）を閉塞させる。また酸化変質油に含まれる酸性成分又はスラッジは被処理油中の水と交わり酸性を呈するため、例えば回収油貯蔵タンク１７から回収絶縁油を払出すラインの配管等を腐食させる。さらに減圧蒸留槽２３で水分を除去すると水溶性の酸化変質油もスラッジとなって析出し、減圧蒸留槽２３と反応槽２５を結ぶラインに設けられたストレーナ（図示を省略）を閉塞させる。また酸化変質油を含むＰＣＢ微量混入絶縁油を被処理油とし、これを金属ナトリウムさらに反応促進剤である水と反応させると、次に示すように酸化変質油も金属ナトリウムと反応するため、金属ナトリウムの消費量が多くなる。酸化変質油を含むＰＣＢ微量混入絶縁油と金属ナトリウム、反応促進剤である水との代表的な反応は、次式で示される。さらに酸化変質油が金属ナトリウム、反応促進剤と反応し生成する鹸化物、炭酸塩、有機酸塩等は、絶縁油には溶解せずかつ極性が強いため金属面に付着し易く、これらが壁面に付着、成長しスケールとなることで種々のトラブルを発生させる。 When the PCB mixed insulating oil detoxification treatment equipment 1 is used to process the PCB mixed insulating oil containing oxidized and denatured oil, the sludge to be deposited is tar and highly viscous. For example, the recovered insulating oil is collected from the recovered oil storage tank 17. A strainer (not shown) provided in the payout line is closed. In addition, since the acidic component or sludge contained in the oxidized modified oil is mixed with the water in the oil to be treated and exhibits acidity, for example, the piping of the line for discharging the recovered insulating oil from the recovered oil storage tank 17 is corroded. Further, when water is removed in the vacuum distillation tank 23, water-soluble oxidized and denatured oil is also precipitated as sludge, and a strainer (not shown) provided in a line connecting the vacuum distillation tank 23 and the reaction tank 25 is closed. In addition, PCB trace mixed insulating oil containing oxidized modified oil is treated oil, and when this is reacted with metal sodium and water as a reaction accelerator, oxidized modified oil also reacts with metallic sodium as shown below. Increased consumption of sodium. A typical reaction between a PCB trace-mixed insulating oil containing oxidized denatured oil, metallic sodium, and water as a reaction accelerator is represented by the following formula. Furthermore, saponified products, carbonates, organic acid salts, etc. produced by the reaction of oxidized modified oil with metallic sodium and reaction accelerators do not dissolve in insulating oil and are strong in polarity, so they easily adhere to the metal surface. Various troubles occur due to adhesion and growth to scale.

前記酸化変質油に伴うトラブル、設備及びプロセスに及ぼす悪影響を防止するため本発明に係るＰＣＢ混入絶縁油の無害化処理方法では、酸化変質油を含むＰＣＢ混入絶縁油を処理するに際し、水分を除去する前までに、被処理油に金属酸化物、金属水酸化物及び炭酸塩のうち１種以上を添加する。 In the detoxification treatment method for PCB-mixed insulating oil according to the present invention in order to prevent troubles associated with the oxidized and denatured oil, adverse effects on facilities and processes, the moisture is removed when the PCB-mixed insulating oil containing oxidized and denatured oil is processed. Before doing so, at least one of metal oxide, metal hydroxide and carbonate is added to the oil to be treated.

酸化変質油を含むＰＣＢ混入絶縁油へ添加する金属酸化物、金属水酸化物及び炭酸塩は、アルカリ金属、アルカリ土類金属、アルミニウムの酸化物、水酸化物及び炭酸塩を使用することが可能であり、金属酸化物としてＮａ_２Ｏ、Ｋ_２Ｏ、ＣａＯ、ＭｇＯ、Ａｌ_２Ｏ_３、金属水酸化物としてＮａＯＨ、ＫＯＨ、Ｃａ（ＯＨ）_２、Ｍｇ（ＯＨ）_２、Ａｌ（ＯＨ）_３、炭酸塩としてＮａ_２ＣＯ_３、Ｋ_２ＣＯ_３、ＮａＨＣＯ_３が例示される。 Metal oxides, metal hydroxides and carbonates added to PCB-mixed insulating oils, including oxidized and denatured oils, can use alkali metals, alkaline earth metals, aluminum oxides, hydroxides and carbonates. Na ₂ O, K ₂ O, CaO, MgO, Al ₂ O ₃ as metal oxides, NaOH, KOH, Ca (OH) ₂ , Mg (OH) ₂ , Al (OH) ₃ as metal hydroxides Examples of the carbonate include Na ₂ CO ₃ , K ₂ CO ₃ , and NaHCO ₃ .

金属酸化物、金属水酸化物、炭酸塩は、１種類の金属酸化物、金属水酸化物又は炭酸塩を添加しても又は２種類の金属酸化物、さらには金属酸化物と炭酸塩とを同時に添加してもよい。金属酸化物、金属水酸化物、炭酸塩は、これらを直接、酸化変質油を含むＰＣＢ混入絶縁油に添加してもよいが、灯油などの鉱油に分散させスラリー溶液として添加すれば取り扱いが容易となり、さらに酸化変質油を含むＰＣＢ混入絶縁油中での分散性も高まる。灯油などの鉱油に金属酸化物、金属水酸化物、炭酸塩を分散させる場合、少量の界面活性剤を添加することで分散性が高まる。直接添加する場合、スラリー溶液として添加する場合とも、酸化変質油との接触、反応の点から添加する金属酸化物、金属水酸化物及び炭酸塩の粒径は小さい方が好ましく、例えば数μｍ程度の大きさが好ましい。添加量は、酸化変質油の量に応じて適宜決定すればよい。 Metal oxide, metal hydroxide and carbonate can be added with one kind of metal oxide, metal hydroxide or carbonate, or two kinds of metal oxide, and further metal oxide and carbonate. You may add simultaneously. Metal oxides, metal hydroxides, and carbonates may be added directly to PCB-mixed insulating oils containing oxidized and altered oils, but are easy to handle if dispersed in mineral oil such as kerosene and added as slurry solutions Furthermore, the dispersibility in the PCB-mixed insulating oil containing the oxidized modified oil is also increased. When a metal oxide, metal hydroxide, or carbonate is dispersed in mineral oil such as kerosene, dispersibility is enhanced by adding a small amount of a surfactant. When adding directly or when adding as a slurry solution, it is preferable that the particle size of the metal oxide, metal hydroxide and carbonate added from the point of contact with the oxidized modified oil and reaction is smaller, for example, about several μm Is preferred. What is necessary is just to determine an addition amount suitably according to the quantity of oxidation alteration oil.

金属酸化物、金属水酸化物、炭酸塩の添加は、減圧蒸留槽２３で水分を除去するまでに行う。添加場所としては、減圧蒸留槽２３よりも上流側の装置、配管等で行うことができ、添加の容易性、酸化変質油を含むＰＣＢ混入絶縁油との攪拌混合を考慮すれば、回収油貯蔵タンク１７、回収絶縁油を輸送するタンクローリー１９、タンクローリー１９と処理タンク２１とを結ぶ払出しライン、処理タンク２１、処理タンク２１と減圧蒸留槽２３とを結ぶ払出しラインが好ましい。特にタンクローリー１９に金属酸化物、金属水酸化物、炭酸塩を添加すれば、添加が容易である他、回収絶縁油の充填時、輸送時、さらには払出し時にも攪拌されるので好ましい。図１中Ａ〜Ｅは、金属酸化物、金属水酸化物、炭酸塩の添加場所を示す。 Addition of the metal oxide, metal hydroxide, and carbonate is performed until the moisture is removed in the vacuum distillation tank 23. The place of addition can be carried out by equipment, piping, etc. upstream from the vacuum distillation tank 23. Considering ease of addition and stirring and mixing with insulating oil mixed with PCB containing oxidized denatured oil, recovered oil storage The tank 17, the tank lorry 19 for transporting the recovered insulating oil, the discharge line connecting the tank lorry 19 and the processing tank 21, and the discharge line connecting the processing tank 21, the processing tank 21 and the vacuum distillation tank 23 are preferable. In particular, it is preferable to add a metal oxide, a metal hydroxide, or a carbonate to the tank lorry 19 because the addition is easy and the agitation is performed at the time of filling the recovered insulating oil, at the time of transport, and at the time of discharging. In FIG. 1, A to E indicate locations where metal oxides, metal hydroxides, and carbonates are added.

より好ましい態様としては、回収油貯蔵タンク１７にＭｇ（ＯＨ）_２を添加し、さらに処理タンク２１にＮａＯＨ及びＮａ_２ＣＯ_３を添加する。 In a more preferred embodiment, Mg (OH) ₂ is added to the recovered oil storage tank 17, and NaOH and Na ₂ CO ₃ are added to the processing tank 21.

回収油貯蔵タンク１７にＭｇ（ＯＨ）_２を添加すると、Ｍｇ（ＯＨ）_２は、回収絶縁油に含まれる水と接しアルカリ性を呈するので酸化変質油に含まれる酸性成分を中和し、酸化変質油が引き起こす配管の腐食等を防止することができる。灯油に分散させた３０重量％Ｍｇ（ＯＨ）_２スラリーを回収絶縁油に対して０．２重量％添加したところ、回収絶縁油のｐＨは約９であり、添加量を０．４重量％まで増加させてもｐＨは変化しなかった。防錆効果はｐＨ９付近が一番高く、この点からＭｇ（ＯＨ）_２は好ましい。 When Mg (OH) ₂ is added to the recovered oil storage tank 17, Mg (OH) ₂ comes into contact with water contained in the recovered insulating oil and exhibits alkalinity. Corrosion of piping caused by oil can be prevented. When 0.2 wt% of 30 wt% Mg (OH) ₂ slurry dispersed in kerosene was added to the recovered insulating oil, the pH of the recovered insulating oil was about 9, and the added amount was up to 0.4 wt% Increasing the pH did not change. The rust prevention effect is highest around pH 9, and Mg (OH) ₂ is preferable from this point.

また回収油貯蔵タンク１７にＭｇ（ＯＨ）_２を添加すると、酸化変質油の極性が緩和されスラッジの析出を防止し、析出したスラッジを分散させることができる。ビーカースケール実験において、タール状で粘性が高いスラッジが析出した酸化変質油を含むＰＣＢ微量混入絶縁油に、灯油に分散させた３０重量％Ｍｇ（ＯＨ）_２スラリーを添加しよく攪拌したところ、スラッジは溶解又は微細化され、ＰＣＢ微量混入絶縁油は濁った状態の一相となり、長時間放置後もスラッジが析出することはなかった。なお、Ｍｇ（ＯＨ）_２の代わりにＮａＯＨで同様の実験を行ったところ、スラッジは小さくなり、かつ粘性が低下した。 Further, when Mg (OH) ₂ is added to the recovered oil storage tank 17, the polarity of the oxidized and denatured oil is relaxed to prevent the sludge from depositing, and the precipitated sludge can be dispersed. In a beaker scale experiment, when 30 wt% Mg (OH) ₂ slurry dispersed in kerosene was added to a trace amount of insulating oil containing PCB and oxidized oxidation oil on which sludge with high viscosity was deposited, the mixture was stirred well. Was dissolved or refined, and the PCB trace amount insulating oil became one phase in a cloudy state, and sludge did not precipitate even after being left for a long time. In addition, when the same experiment was conducted with NaOH instead of Mg (OH) ₂ , the sludge became smaller and the viscosity decreased.

上記のように回収油貯蔵タンク１７にＭｇ（ＯＨ）_２を添加することで、酸化変質油に含まれる酸性成分が中和されこれにより安定的に回収絶縁油を貯蔵することができる。また酸化変質油の極性を緩和させ酸化変質油のスラッジ化を防止し又はスラッジ化した酸化変質油を分散させることができるので、スラッジによるストレーナ、配管の閉塞を防止することができる。なお、Ｍｇ（ＯＨ）_２に代えＭｇＯを添加すると、ＭｇＯは回収絶縁油に含まれる水と反応してＭｇ（ＯＨ）_２になるので、ＭｇＯを添加してもよい。この他、Ｎａ_２ＣＯ_３及びＮａＨＣＯ_３の添加も酸性成分の中和には好ましい。 By adding Mg (OH) ₂ to the recovered oil storage tank 17 as described above, the acidic component contained in the oxidized modified oil is neutralized, and thus the recovered insulating oil can be stored stably. Moreover, since the polarity of the oxidized modified oil can be relaxed to prevent the oxidized modified oil from becoming sludge or the sludge oxidized oxidized modified oil can be dispersed, it is possible to prevent the strainer and piping from being blocked by the sludge. When MgO is added instead of Mg (OH) ₂ , MgO reacts with the water contained in the recovered insulating oil to become Mg (OH) ₂ , so MgO may be added. In addition, addition of Na ₂ CO ₃ and NaHCO ₃ is also preferable for neutralization of acidic components.

処理タンク２１にＮａＯＨ及びＮａ_２ＣＯ_３を添加すると、これらにＭｇ（ＯＨ）_２を含む被処理油は、減圧蒸留槽２３で加熱、減圧され水分が除去される。被処理油中の水分が除去されると水溶性の酸化変質油が析出するが、析出する酸化変質油、スラッジとなり析出した酸化変質油及び非水溶性で被処理油に溶解する酸化変質油は、ＮａＯＨ、Ｎａ_２ＣＯ_３、Ｍｇ（ＯＨ）_２と反応する。以下、酸化変質油と金属酸化物、金属水酸化物との代表的な反応例を示す。鹸化反応及びフェノキシド塩反応は、ｐＨが高い方が進み易いのでＮａＯＨを添加することは好ましい。なお、灯油に分散させた３０重量％ＮａＯＨスラリーを回収絶縁油に対して０．１２重量％添加したところ、回収絶縁油のｐＨは約１３．２であり、添加量を０．４重量％まで増加させてもｐＨは変化しなかった。 When NaOH and Na ₂ CO ₃ are added to the treatment tank 21, the oil to be treated containing Mg (OH) ₂ is heated and decompressed in the vacuum distillation tank 23 to remove moisture. When water in the oil to be treated is removed, a water-soluble oxidized oil is precipitated, but the oxidized oil that is precipitated, oxidized oil that has become sludge and oxidized water that is water-insoluble and dissolves in the oil to be treated are , NaOH, Na ₂ CO _3, Mg (OH) ₂ . Hereinafter, typical reaction examples of the oxidized modified oil, the metal oxide, and the metal hydroxide are shown. In the saponification reaction and the phenoxide salt reaction, it is preferable to add NaOH because the pH is higher when the reaction proceeds. In addition, when 0.12 wt% of 30 wt% NaOH slurry dispersed in kerosene was added to the recovered insulating oil, the pH of the recovered insulating oil was about 13.2 and the addition amount was up to 0.4 wt%. Increasing the pH did not change.

減圧蒸留槽２３では、上記のように酸化変質油が金属酸化物、金属水酸化物、炭酸塩と反応することで、スラッジの析出を防止し、又はスラッジを微細化するので配管等の閉塞を防止することができる。上記鹸化反応及びフェノキシド塩反応で代表される酸化変質油と金属酸化物、金属水酸化物、炭酸塩との反応は、金属酸化物、金属水酸化物、炭酸塩の添加を減圧蒸留槽２３で水分を除去するまでに行っておくことで、減圧蒸留槽２３での被処理油からの水分除去操作と同時に行うことができる。 In the vacuum distillation tank 23, the oxidized and modified oil reacts with the metal oxide, metal hydroxide, and carbonate as described above, thereby preventing sludge precipitation or making the sludge fine so that the pipes and the like are blocked. Can be prevented. The reaction between the oxidatively modified oil represented by the saponification reaction and the phenoxide salt reaction and the metal oxide, metal hydroxide and carbonate is carried out by adding the metal oxide, metal hydroxide and carbonate in the vacuum distillation tank 23. By performing the process before removing the water, it can be performed simultaneously with the operation of removing the water from the oil to be treated in the vacuum distillation tank 23.

基礎実験において、灯油に分散させた３０重量％ＮａＯＨスラリー又は３０重量％Ｍｇ（ＯＨ）_２スラリーを回収絶縁油に対して０．２重量％添加し、この油をロータリーエバポレータで減圧蒸留したところ、フラスコ内には殆ど残渣が見られなかった。一方、酸化変質油を含むＰＣＢ混入絶縁油をそのままロータリーエバポレータで減圧蒸留したところ、フラスコ内に比較的多くの褐色の残渣が認められた。 In the basic experiment, 0.2 wt% of 30 wt% NaOH slurry or 30 wt% Mg (OH) ₂ slurry dispersed in kerosene was added to the recovered insulating oil, and this oil was distilled under reduced pressure using a rotary evaporator. Almost no residue was found in the flask. On the other hand, when PCB-containing insulating oil containing oxidized and denatured oil was directly distilled under reduced pressure using a rotary evaporator, a relatively large amount of brown residue was found in the flask.

鹸化反応及びフェノキシド塩反応で生じた反応生成物を含む被処理油は、反応槽２５に送られ、ここで金属ナトリウムが添加されるが、鹸化反応及びフェノキシド塩反応で生じた反応生成物は金属ナトリウムと反応せず、さらに酸化変質油の量も低減しているので反応槽２５で添加する金属ナトリウムの量を抑えることができる。図３に被処理油にＮａＯＨ又はＭｇ（ＯＨ）_２を添加したときの反応槽２５に添加する金属ナトリウム注入量と反応後の処理済油中のＰＣＢ濃度の関係を示した。 The oil to be treated containing the reaction product generated by the saponification reaction and the phenoxide salt reaction is sent to the reaction vessel 25, where metallic sodium is added, but the reaction product generated by the saponification reaction and the phenoxide salt reaction is a metal. Since it does not react with sodium and the amount of oxidized and modified oil is also reduced, the amount of metallic sodium added in the reaction tank 25 can be suppressed. FIG. 3 shows the relationship between the injection amount of metallic sodium added to the reaction tank 25 when NaOH or Mg (OH) ₂ is added to the oil to be treated and the PCB concentration in the treated oil after the reaction.

灯油に分散させた３０重量％ＮａＯＨスラリー又は３０重量％Ｍｇ（ＯＨ）_２スラリーを回収絶縁油に対して０．２重量％添加したところ、１２ｍｇ／ｋｇＰＣＢ混入絶縁油を完全に分解するに必要な金属ナトリウムの量は、被処理油１ｋＬ当たり前者で約０．７５ｋｇ、後者で約１．２ｋｇであった。全く金属酸化物、金属水酸化物、炭酸塩を添加しない場合、被処理油１ｋＬ当たり金属ナトリウムを約１．４ｋｇ添加する必要があることから、ＮａＯＨ又はＭｇ（ＯＨ）_２を添加することで金属ナトリウムの添加量を大幅に低減させることができる。なお、酸化変質油を全く含まないＰＣＢ混入絶縁油の場合、ＰＣＢを完全に分解するに必要な金属ナトリウムの量は被処理油１ｋＬ当たり約０．５５ｋｇであった。 When 0.2 wt% of 30 wt% NaOH slurry or 30 wt% Mg (OH) ₂ slurry dispersed in kerosene is added to the recovered insulating oil, it is necessary to completely decompose the 12 mg / kg PCB mixed insulating oil. The amount of metallic sodium was about 0.75 kg in the former and about 1.2 kg in the latter per 1 kL of the oil to be treated. When no metal oxide, metal hydroxide, or carbonate is added, it is necessary to add about 1.4 kg of metal sodium per 1 liter of oil to be treated. Therefore, by adding NaOH or Mg (OH) ₂ , The amount of sodium added can be greatly reduced. In the case of an insulating oil mixed with PCB that does not contain any oxidatively altered oil, the amount of metallic sodium required to completely decompose the PCB was about 0.55 kg per 1 liter of oil to be treated.

従来のＰＣＢ混入絶縁油の無害化処理方法では、反応槽２５の壁面にスケールが付着する現象がよく見られた。スケールは、酸化変質油が金属ナトリウム又は反応促進剤と反応し生成する鹸化物、炭酸塩、有機酸塩でありこれらが反応槽内壁面へ付着し、析出したものである。これら鹸化物、炭酸塩、有機酸塩は極性が強いため金属面に付着しやすく油に不溶であるので反応槽２５の壁面に付着し、種々の悪影響を与えるが、本発明に係るＰＣＢ混入絶縁油の無害化処理方法では、反応槽２５には酸化変質油と金属酸化物、金属水酸化物、炭酸塩とを反応させた被処理油が送られるのでスケールの発生が抑制される。なお酸化変質油と金属酸化物、金属水酸化物、炭酸塩との反応生成物は、処理済油と一緒に通常の処理工程で処理されるので、別途、処理工程を設ける必要がなく、本発明に係るＰＣＢ混入絶縁油の無害化処理方法は実用的な方法と言える。 In the conventional detoxification treatment method for PCB-mixed insulating oil, a phenomenon in which scale adheres to the wall surface of the reaction tank 25 is often observed. The scale is a saponified product, carbonate or organic acid salt produced by the reaction of oxidized modified oil with metallic sodium or a reaction accelerator, which adheres to the inner wall of the reaction tank and precipitates. Since these saponified products, carbonates and organic acid salts are strong in polarity and easily adhere to the metal surface and are insoluble in oil, they adhere to the wall surface of the reaction tank 25 and have various adverse effects. In the oil detoxification treatment method, the reaction tank 25 is fed with the oil to be treated in which the oxidized denatured oil and the metal oxide, metal hydroxide, and carbonate are reacted with each other, so that generation of scale is suppressed. The reaction product of oxidized and altered oil and metal oxide, metal hydroxide, and carbonate is processed in the normal processing step together with the treated oil, so there is no need to provide a separate processing step. It can be said that the detoxification treatment method for PCB-containing insulating oil according to the invention is a practical method.

また被処理油に炭酸塩を添加しておくことで、炭酸塩が種晶となる。処理タンク２１にＮａ_２ＣＯ_３を添加すると、Ｎａ_２ＣＯ_３は被処理油といっしょに反応槽２５に送られ、酸化変質油と金属ナトリウム又は反応促進剤とが反応し鹸化物、炭酸塩、有機酸塩等が生成しても、これら反応生成物はＮａ_２ＣＯ_３を種晶としこれに付着し種晶を核として成長するので、反応生成物が反応槽内壁面に付着することをより確実に防止することができる。Ｎａ_２ＣＯ_３に付着する鹸化物、炭酸塩、有機酸塩等の反応生成物は不溶性固形分となり、処理済油中に懸濁し、処理済油と共に分解確認槽２７を経由して抽出中和槽３１へ送られる。抽出中和槽３１には多量の水が加えられるので、鹸化物、炭酸塩、有機酸塩等は水に溶解し、最終的には、塩化ナトリウムなどと一緒に乾燥汚泥として回収される。 Further, by adding a carbonate to the oil to be treated, the carbonate becomes a seed crystal. When Na ₂ CO ₃ is added to the treatment tank 21, the Na ₂ CO ₃ is sent to the reaction tank 25 together with the oil to be treated, and the oxidized denatured oil reacts with metallic sodium or a reaction accelerator to react with a saponified product, carbonate, Even if an organic acid salt or the like is generated, these reaction products grow using Na ₂ CO ₃ as a seed crystal and adhere to this seed crystal as a nucleus, so that the reaction product adheres to the inner wall of the reaction vessel. It can be surely prevented. Reaction products such as saponified products, carbonates and organic acid salts adhering to Na ₂ CO ₃ become insoluble solids, suspended in the treated oil, and neutralized by extraction through the decomposition confirmation tank 27 together with the treated oil. It is sent to the tank 31. Since a large amount of water is added to the extraction neutralization tank 31, saponified products, carbonates, organic acid salts and the like are dissolved in water, and finally recovered as dry sludge together with sodium chloride and the like.

以上のように本発明に係るＰＣＢ混入絶縁油の無害化処理方法は、簡便な方法ながら、従来、酸化変質油を含むＰＣＢ混入絶縁油を処理するとき発生していたトラブル、設備及び運転に及ぼす悪影響を防止することができる。これによりＰＣＢ混入絶縁油の無害化処理を安定的に行うことができる。 As described above, the detoxification treatment method for PCB-mixed insulating oil according to the present invention affects troubles, facilities, and operations that have conventionally occurred when processing PCB-mixed insulating oil containing oxidized denatured oil, while being a simple method. Adverse effects can be prevented. Thereby, the detoxification process of the PCB mixed insulating oil can be stably performed.

１ＰＣＢ混入絶縁油無害化処理設備
２絶縁油回収装置
３無害化処理装置
１１真空加熱炉
１３凝縮器
１５油水分離器
１７回収油貯蔵タンク
１９タンクローリー
２１処理タンク
２３減圧蒸留槽
２５反応槽
２７分解確認槽
２９サンプリングライン
３１抽出中和槽
３３油水分離槽
３５洗浄水再生設備
３７油相
３９水相
４１処理済油タンク
４３乾燥機
４５静置分離水受槽
４７凝縮器
４９凝縮水槽 DESCRIPTION OF SYMBOLS 1 PCB-mixed insulating oil detoxification processing equipment 2 Insulating oil recovery device 3 Detoxification processing device 11 Vacuum heating furnace 13 Condenser 15 Oil-water separator 17 Recovery oil storage tank 19 Tank lorry 21 Processing tank 23 Vacuum distillation tank 25 Reaction tank 27 Confirmation of decomposition Tank 29 Sampling Line 31 Extraction Neutralization Tank 33 Oil Water Separation Tank 35 Wash Water Recycling Equipment 37 Oil Phase 39 Water Phase 41 Treated Oil Tank 43 Dryer 45 Stationary Separated Water Receiving Tank 47 Condenser 49 Condensed Water Tank

Claims

不純物を含むＰＣＢ混入絶縁油を被処理油とし、該被処理油に含まれる水分を除去した後に金属ナトリウムとＰＣＢとを反応させ被処理油を無害化するＰＣＢ混入絶縁油の無害化処理方法において、
前記被処理油が紙木類乾留物を含むＰＣＢ混入絶縁油で、不純物が酸化変質油であり、
遅くとも被処理油に含まれる水分を除去する前までに、前記被処理油に金属酸化物、金属水酸化物及び炭酸塩のうち１種以上を添加することを特徴とするＰＣＢ混入絶縁油の無害化処理方法。 In a detoxifying treatment method for PCB-containing insulating oil, a PCB-mixed insulating oil containing impurities is treated as an oil to be treated, and after removing moisture contained in the oil to be treated, metal sodium and PCB are reacted to detoxify the treated oil. ,
The treated oil is a PCB-mixed insulating oil containing a paper-wood dry matter, and the impurity is an oxidized modified oil
Harmless to PCB-containing insulating oil, wherein at least one of metal oxide, metal hydroxide and carbonate is added to the oil to be treated before removing water contained in the oil to be treated at the latest Processing method.

前記酸化変質油は、Ｃ＝Ｏ結合及びＣ−Ｏ結合を含むことを特徴とする請求項１に記載のＰＣＢ混入絶縁油の無害化処理方法。 The method for detoxifying PCB-containing insulating oil according to claim 1, wherein the oxidized and denatured oil includes C═O bond and C—O bond.

前記金属酸化物、金属水酸化物及び炭酸塩が、アルカリ金属、アルカリ土類金属、アルミニウムの酸化物、水酸化物及び炭酸塩であることを特徴とする請求項１又は２に記載のＰＣＢ混入絶縁油の無害化処理方法。 The PCB contamination according to claim 1 or 2, wherein the metal oxide, metal hydroxide, and carbonate are alkali metal, alkaline earth metal, aluminum oxide, hydroxide, and carbonate. Detoxification method for insulating oil.

前記被処理油は、少なくともＰＣＢ汚染物を真空加熱し回収される回収絶縁油を含み、前記紙木類乾留物は前記回収絶縁油に含まれることを特徴とする請求項１から３のいずれか１に記載のＰＣＢ混入絶縁油の無害化処理方法。 The said to-be-processed oil contains the collection | recovery insulating oil collect | recovered by vacuum-heating at least PCB contaminant, The said paper-wood dry distillation thing is contained in the said collection | recovery insulation oil, The any one of Claim 1 to 3 The method for detoxifying PCB-containing insulating oil according to 1.

ＰＣＢと金属ナトリウムとを反応させるに先立ち、前記金属酸化物、金属水酸化物及び炭酸塩のうち１種以上が添加された被処理油を加熱及び減圧し、添加された前記金属酸化物、金属水酸化物及び炭酸塩のうち１種以上と前記酸化変質油とを反応させることを特徴とする請求項１から４のいずれか１に記載のＰＣＢ混入絶縁油の無害化処理方法。 Prior to reacting the PCB and metal sodium, the metal oxide, the treated oil which one or more are added of the metal hydroxides and carbonates heating and under reduced pressure, the added the metal oxide, metal The method for detoxifying PCB-containing insulating oil according to any one of claims 1 to 4, wherein at least one of hydroxide and carbonate is reacted with the oxidized modified oil.

ＰＣＢ汚染物を真空加熱し回収する回収絶縁油を貯蔵する回収油貯蔵タンクと、前記回収油貯蔵タンクに貯蔵する回収絶縁油を輸送するタンクローリーと、前記タンクローリーから払出される回収絶縁油を含むＰＣＢ混入絶縁油を貯蔵する処理タンクと、前記処理タンクから払出される被処理油を受入れ被処理油から水分を除去する減圧蒸留槽と、水分が除去された被処理油を金属ナトリウムで無害化する反応槽とを備えるＰＣＢ混入絶縁油無害化処理設備を用いＰＣＢ混入絶縁油を無害化処理するとき、
前記回収油貯蔵タンク、前記タンクローリー、前記タンクローリーと前記処理タンクとを結ぶ払出しライン、前記処理タンク及び前記処理タンクと前記減圧蒸留槽とを結ぶ払出しラインのうち少なくともいずれか１の場所で、遅くとも被処理油に含まれる水分を除去する前までに前記金属酸化物、金属水酸化物及び炭酸塩のうち１種以上を添加することを特徴とする請求項４又は５に記載のＰＣＢ混入絶縁油の無害化処理方法。 A PCB including a recovered oil storage tank for storing recovered insulating oil for vacuum heating and recovering PCB contaminants, a tank lorry for transporting recovered insulating oil stored in the recovered oil storage tank, and a recovered insulating oil discharged from the tank lorry A processing tank for storing mixed insulating oil, a vacuum distillation tank for receiving the processing oil discharged from the processing tank and removing water from the processing oil, and detoxifying the processing oil from which water has been removed with sodium metal When detoxifying PCB mixed insulating oil using a PCB mixed insulating oil detoxifying treatment facility equipped with a reaction tank,
At least one of the recovered oil storage tank, the tank lorry, a discharge line connecting the tank lorry and the processing tank, and a discharge line connecting the processing tank and the processing tank and the vacuum distillation tank at the latest. 6. The PCB-containing insulating oil according to claim 4 , wherein at least one of the metal oxide, the metal hydroxide, and the carbonate is added before removing water contained in the treatment oil. Detoxification treatment method.

前記金属酸化物、金属水酸化物及び炭酸塩のうち１種以上の添加が、前記回収油貯蔵タンク、前記タンクローリー、前記タンクローリーと前記処理タンクとを結ぶ払出しライン及び前記処理タンクのうち少なくともいずれか１の場所で、遅くとも被処理油に含まれる水分を除去する前までに水酸化マグネシウムを添加することであり、かつ前記処理タンク及び前記処理タンクと前記減圧蒸留槽とを結ぶ払出しラインのうち少なくともいずれか１の場所で、遅くとも被処理油に含まれる水分を除去する前までにナトリウム及び／又はカリウムの酸化物及び／又は水酸化物を添加することであることを特徴とする請求項６に記載のＰＣＢ混入絶縁油の無害化処理方法。 The addition of one or more of the metal oxide, metal hydroxide and carbonate is at least one of the recovered oil storage tank, the tank lorry, a discharge line connecting the tank lorry and the processing tank, and the processing tank. At least one of the discharge lines connecting the processing tank and the processing tank to the vacuum distillation tank at least before adding water before removing water contained in the oil to be processed. 7. In any one place, it is adding the oxide and / or hydroxide of sodium and / or potassium before removing the water | moisture content contained in a to-be-processed oil at the latest at the point of Claim 6 characterized by the above-mentioned. The method for detoxifying PCB-containing insulating oil as described.

前記ナトリウム及び／又はカリウムの酸化物及び／又は水酸化物の添加と共に、前記処理タンク及び前記処理タンクと前記減圧蒸留槽とを結ぶ払出しラインのうち少なくともいずれか１の場所で、遅くとも被処理油に含まれる水分を除去する前までにナトリウム及び／又はカリウムの炭酸塩を添加することを特徴とする請求項７に記載のＰＣＢ混入絶縁油の無害化処理方法。 With the addition of sodium and / or potassium oxides and / or hydroxides, at least one of the treatment tank and the discharge line connecting the treatment tank and the vacuum distillation tank, the oil to be treated at the latest The method for detoxifying PCB-containing insulating oil according to claim 7, wherein sodium and / or potassium carbonate is added before the moisture contained in the water is removed .