JP2014085325A - Waste liquid treating system and waste liquid treating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waste liquid treating system capable of reducing the generation amount of secondary waste of high dose generated when decontamination waste liquid is treated, and provide a treating method of the decontamination waste liquid.SOLUTION: The waste liquid treating system 13 of the present invention includes: a first adsorption tower 32; a second adsorption tower 33; a third adsorption tower 34; a fourth adsorption tower 35; a fifth adsorption tower 36; a decontamination waste liquid circulation line L11; a first bypass line L22; and a second bypass line L23. A first resin 41 and fourth resin 42 can be buried as waste, and second resins 43A and 43B and a third resin 44 can be incinerated to be reduced in volume. Therefore, treating decontamination waste liquid 14 can reduce the generation amount of the secondary waste of high dose, which is difficult to be buried.

Description

  The present invention relates to a waste liquid treatment system and a waste liquid treatment method.

  In radiation handling facilities such as nuclear power plants and spent fuel reprocessing plants, structural parts such as pipes that come into contact with radioactive liquid waste containing radioactive materials are associated with the operation of nuclear power plants and reprocessing plants in radiation handling facilities. A film such as an oxide or salt containing a radioactive substance adheres to or forms on the inner surface. If the operation period of the facility becomes longer, the radiation dose around pipes and equipment increases, and there is a risk that the dose of workers will be increased during periodic inspections, maintenance work, or waste demolition work. In order to reduce the exposure of workers, it is necessary to remove (decontaminate) radioactive substances adhering to piping and equipment.

  A typical reactor to be decontaminated is a reactor primary cooling system (primary cooling system). A scale called a clad containing a radioactive substance is attached to the primary cooling system. This cladding serves as a radiation source for workers to receive radiation exposure around the primary cooling system piping and equipment. In order to reduce radiation exposure and improve the working environment, it is necessary to remove the cladding and decontaminate piping and equipment. For decontamination of piping and equipment, for example, a chemical decontamination method in which chemical treatment is performed using a chemical is used.

  In addition, decontamination waste liquid generated by decontamination of equipment in such a radiation handling facility is used to chemically remove radioactive substances such as metal ions contained in the decontamination solution using an ion exchange resin such as a cation resin or anion resin. Has been proposed (for example, see Patent Documents 1 and 2).

JP 2004-45371 A Japanese Patent No. 2509654

  In the waste liquid treatment method for decontamination waste liquid, ion exchange resins such as cation resin and mixed bed resin (mixture of cation resin and anion resin) used for treatment of metal ions in decontamination waste liquid are used as secondary waste. Although used, the used ion exchange resin has a high dose, so that incineration is difficult. In addition, since the cation resin is an organic substance and the mixed bed resin is an organic substance and contains a chelate compound (metal chelate), it is possible to solidify the ion exchange resin into a solid substance and bury it in a disposal site. Have difficulty.

  High-dose organic matter causes hydrogen gas to be generated by radioactive decomposition. In addition, the chelate compound promotes nuclide migration and causes the barrier performance of the disposal site to deteriorate. For these reasons, the ion exchange resin and the chelate compound used for the treatment of the decontamination waste liquid are not allowed to be buried. Therefore, the ion exchange resin generated as secondary waste cannot be disposed of and must be stored in the nuclear power plant.

  Therefore, in order to reduce the amount of high-dose used ion exchange resin that is difficult to be buried, further improvement is required.

  The present invention has been made in view of the above, and a waste liquid treatment system capable of reducing the amount of high-dose secondary waste generated when processing decontamination waste liquid and the treatment of decontamination waste liquid It aims to provide a method.

  The first invention of the present invention for solving the above-described problem is to extract a decontamination waste liquid generated from a chemical used in a decontamination target of a nuclear reactor facility and circulate it to the decontamination target of the nuclear reactor facility. Dissolved from the decontamination waste liquid treatment line and the metal ion dissolved from the oxide film present in the decontamination target of the nuclear reactor equipment or the oxide film contained in the decontamination waste liquid provided in the decontamination waste liquid treatment line At least one first adsorbing portion including a first resin that adsorbs at least a chelate compound formed by chelating bond of an organic acid with an organic acid, and is included in the decontamination waste liquid treatment line. A second adsorbing unit comprising at least a second resin that adsorbs the organic acid, a first bypass line provided to bypass the second adsorbing unit of the decontamination waste liquid treatment line, and a decontamination waste liquid treatment line A second bypass line provided by bypassing the first adsorbing part and the second adsorbing part, and a second bypass line provided at the second bypass line for at least adsorbing metal ions of the oxidant contained in the decontamination waste liquid. A waste liquid treatment system comprising: a third adsorption unit comprising three resins.

  A second invention is the first invention, comprising a fourth resin provided between the first adsorbing part and the second adsorbing part of the decontamination waste liquid treatment line and adsorbing at least the chelate compound. It is a waste liquid processing system characterized by having 4 adsorption parts.

  According to a third invention, in the first or second invention, the decontamination waste liquid is provided upstream of the first adsorption portion of the decontamination waste liquid treatment line in the flow direction of the decontamination waste liquid, and is included in the decontamination waste liquid. A waste liquid treatment system including a separation unit for removing precipitates.

  According to a fourth invention, in any one of the first to third inventions, the first resin includes at least a cation resin or an inorganic adsorbent, and the second resin includes an anion resin, a cation resin, and an anion resin. And at least one of a mixed bed resin mixed with the anionic resin and the mixed bed resin, and the third resin includes at least a cationic resin or an inorganic adsorbent. This is a featured waste liquid treatment system.

  According to a fifth invention, in any one of the second to fourth inventions, the fourth resin is an anion resin, a mixed bed resin in which a cation resin and an anion resin are mixed, the anion resin and the mixture. A waste liquid treatment system comprising at least one of resins mixed with a floor resin.

  6th invention discharges the chemical | medical agent supplied to the decontamination target object of the nuclear reactor equipment from the decontamination target object of the said nuclear reactor equipment as a decontamination waste liquid, and decirculates it to the decontamination target object of the said nuclear reactor equipment A waste liquid circulation line, a chemical supply section for supplying a chemical containing an oxidizing agent or a reducing agent to the decontamination waste liquid circulation line, and the waste liquid treatment system according to any one of the first to fifth inventions, A decontamination waste liquid treatment line is connected to the decontamination waste liquid circulation line.

  The seventh invention of the present invention for solving the above-described problem is that the chemical supplied to the decontamination target of the nuclear reactor facility is discharged from the decontamination target of the nuclear reactor facility as a decontamination waste liquid, and the reactor Connected to the decontamination waste liquid circulation line, a decontamination waste liquid circulation line to be circulated to the decontamination target of the facility, a chemical supply unit for supplying a chemical containing an oxidizing agent or a reducing agent to the decontamination waste liquid circulation line, and the decontamination waste liquid circulation line, A decontamination waste liquid treatment line for extracting the decontamination waste liquid and circulating it to the decontamination target of the nuclear reactor equipment, and an oxide film present in the decontamination target of the nuclear reactor equipment provided in the decontamination waste liquid treatment line. A first adsorbing part comprising a first resin that adsorbs at least a chelate compound formed by chelating a dissolved metal ion or a metal ion dissolved from the oxide film contained in the decontamination waste liquid with an organic acid; Decontamination One or more liquid treatment lines are provided, bypassing the second adsorption part provided with a second resin that at least adsorbs the organic acid contained in the decontamination waste liquid, and the second adsorption part of the decontamination waste liquid treatment line A first bypass line provided; a second bypass line provided by bypassing the first adsorption part and the second adsorption part of the decontamination waste liquid treatment line; An oxidant supply step of supplying an oxidant to the decontamination waste liquid using a waste liquid treatment system having a third adsorbing unit having a third resin that adsorbs at least a metal ion of the oxidant contained in the waste liquid; Adding a chemical agent that decomposes the oxidizing agent, passing all or part of the decontamination waste liquid containing the chemical agent that decomposes the oxidizing agent through the second bypass line and passing through the third adsorption unit, After at least adsorbing metal ions of the oxidant contained in the liquid, an oxidant purification step for supplying the decontamination target of the nuclear reactor equipment, and after adding a reducing agent to the decontamination waste liquid, After passing all or part of the decontamination waste liquid containing the first adsorbing part and adsorbing at least the metal ions dissolved from the oxide film present in the decontamination object of the reactor facility, or the chelate compound, A reduction step of passing through the first bypass line to supply to the decontamination object of the nuclear reactor facility, and a decontamination waste liquid obtained by decomposing the reducing agent after decomposing the reducing agent contained in the decontamination waste liquid Is passed through the first adsorption unit and the second adsorption unit, and adsorbs at least the chelate compound or the organic acid contained in the decontamination target of the nuclear reactor facility, and then the nuclear reactor. Decontamination of equipment Purification step for supplying an object, and starting from the oxidant supply step or the reduction step, the oxidant supply step, the oxidant purification step, the reduction step and the purification step, the oxidant supply step The waste liquid treatment method includes at least once in the order of the oxidizing agent purification step, the reduction step, and the purification step, and ends with the purification step.

  An eighth invention is the seventh invention, comprising: a fourth resin provided between the first adsorbing portion and the second adsorbing portion of the decontamination waste liquid treatment line and adsorbing at least the chelate compound. It is a waste liquid processing method characterized by having 4 adsorption parts.

  According to a ninth invention, in the seventh or eighth invention, precipitates contained in the decontamination waste liquid on the upstream side in the flow direction of the decontamination waste liquid from the first adsorption part of the decontamination waste liquid treatment line Is a waste liquid treatment method characterized by removing water.

  According to a tenth invention, in any one of the seventh to ninth inventions, the first resin includes at least a cation resin or an inorganic adsorbent, and the second resin includes an anion resin, a cation resin, and an anion resin. And at least one of a mixed bed resin mixed with the anionic resin and the mixed bed resin, and the third resin includes at least a cationic resin or an inorganic adsorbent. This is a featured waste liquid treatment method.

  In an eleventh aspect based on any one of the seventh to tenth aspects, the fourth resin comprises an anion resin, a mixed bed resin in which a cation resin and an anion resin are mixed, the anion resin and the mixture. A waste liquid treatment method comprising at least one of resins mixed with a floor resin.

  In a twelfth invention according to any one of the seventh to eleventh inventions, in the oxidant purification step and the reduction step, the decontamination waste liquid, the decontamination waste liquid circulation line, the first bypass line, and the Any one of the second bypass lines and the decontamination target of the nuclear reactor equipment are circulated at least once.

  ADVANTAGE OF THE INVENTION According to this invention, the generation amount of the high dose secondary waste generated when processing a decontamination waste liquid can be reduced.

FIG. 1 is a schematic diagram illustrating a decontamination system including a waste liquid treatment system according to an embodiment of the present invention. FIG. 2 is a flowchart showing an example of a procedure of a decontamination method to which the decontamination waste liquid treatment method according to the embodiment of the present invention is applied. FIG. 3 is an explanatory diagram showing a state in an oxidant supply process in which an oxidant is supplied. FIG. 4 is an explanatory view showing a state in the oxidizing agent purification step. FIG. 5 is an explanatory diagram showing a state in the reduction process. FIG. 6 is an explanatory diagram showing a state in the purification process.

  Hereinafter, embodiments of a waste liquid treatment system and a waste liquid treatment method according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by the following Example. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range. Furthermore, the constituent elements disclosed in the following embodiments can be appropriately combined.

  A case where the waste liquid treatment system according to the embodiment of the present invention is applied to a decontamination system in a nuclear power plant will be described with reference to the drawings. The waste liquid treatment system according to the present embodiment can be applied to all types of nuclear reactors of nuclear power plants. For example, in pressurized water reactors (PWR: Pressurized Water Reactor), improved pressurized water reactors (APWR: Advanced Pressurized Water Reactor) or boiling water reactors (BWR) Can be applied. PWR uses light water as a reactor coolant and neutron moderator, turns it into high-temperature and high-pressure water that does not boil throughout the primary system, and sends this high-temperature and high-pressure water to a steam generator to exchange heat with the secondary coolant. Is generated, and this steam is sent to a turbine generator to generate electricity. Further, the waste liquid treatment system according to the present embodiment can be applied to a radiation handling facility.

<Decontamination system>
FIG. 1 is a schematic diagram illustrating a decontamination system including a waste liquid treatment system according to an embodiment of the present invention. As shown in FIG. 1, the decontamination system 10 is for decontaminating the decontamination object 11 of a nuclear reactor facility. The decontamination system 10 includes a decontamination waste liquid circulation line L11, a chemical supply unit 12, and a waste liquid treatment system 13.

  In addition, decontamination means removing the radioactive substance adhering to piping, equipment, etc. of the system for decontamination of nuclear reactor equipment.

  The decontamination object 11 of the nuclear reactor equipment is a member constituting the nuclear reactor equipment such as nuclear reactor equipment and various pipes. In a nuclear power plant, members constituting a nuclear reactor facility such as nuclear reactor equipment and various pipes are generally made of a steel material such as stainless steel or carbon steel. When these components that make up the nuclear reactor equipment are used, the surfaces of the components making up the nuclear reactor equipment such as nuclear reactor equipment and various pipes are corroded by contact with high-temperature water (primary cooling water). A film is formed. The film is made of at least one metal or oxide of RI, Cr, Fe, and Ni.

  Radioactivity in the reactor water is taken into the coating formed on the wetted parts of the reactor equipment and the inner surface of the piping exposed to high-temperature water (primary cooling water), and it becomes an exposure radiation source.

  The decontamination waste liquid circulation line L11 is a line through which the decontamination waste liquid 14 discharged from the decontamination target 11 of the reactor facility circulates inside and outside the decontamination target 11 of the reactor equipment.

  The drug supply unit 12 includes a first drug supply unit 21, a second drug supply unit 22, a third drug supply unit 23, and a fourth drug supply unit 24. The 1st chemical | medical agent supply part 21 is connected with the decontamination waste liquid circulation line L11 by the 1st chemical | medical agent supply line L12. The 1st chemical | medical agent supply line L12 is a line for sending the 1st chemical | medical agent 26 containing an oxidizing agent from the 1st chemical | medical agent supply part 21 to the decontamination waste liquid circulation line L11. The first medicine supply unit 21 supplies the first medicine 26 to the decontamination waste liquid circulation line L11 through the first medicine supply line L12. The first medicine supply line L12 is provided with a control valve V11 in the middle of the first medicine supply line L12. The supply amount of the first medicine 26 is adjusted by the control valve V11.

Examples of the first agent 26 include hydrogen peroxide (H ₂ O ₂ ), permanganic acid (HMnO ₄ ), permanganate, perferrate, and nitric hydrofluoric acid mixed liquid of nitric acid and hydrofluoric acid. Any one or more of them are used. Specific examples of the permanganate include potassium permanganate (KMnO ₄ ). The first medicine 26 is supplied from the first medicine supply unit 21 to the decontamination waste liquid circulation line L11 through the first medicine supply line L12. The 1st chemical | medical agent 26 oxidizes Cr (III) in the oxide adhering to members, such as the nuclear reactor equipment and various piping which comprise the decontamination target object 11 of a nuclear reactor equipment, to Cr (VI), It melt | dissolves in the 1st chemical | medical agent 26, and removes it from the member which comprises the decontamination target object 11 of a nuclear reactor installation. As a density | concentration of the 1st chemical | medical agent 26, 0.005 mass% or more and 0.5 mass% or less are preferable, More preferably, 0.01 mass% or more and 0.3 mass% or less, More preferably, 0.01 mass% or more 0 .1% by mass or less.

  In the present embodiment, the first drug 26 is used as a drug solution in a liquid state. In the present specification, the drug is used in a concept including any state of liquid, gas, and solid. Therefore, the 1st chemical | medical agent 26 is not limited to the thing of a liquid state, You may use it in the state of either solid or gas. The same applies to other drugs 27, third drug 28, and fourth drug 29 described later.

  By supplying the 1st chemical | medical agent 26 to the decontamination waste liquid circulation line L11, Cr oxide etc. which are contained in the deposit | attachment adhering to the decontamination target object 11 of a nuclear reactor equipment are oxidized at least to Cr (VI). Then, it is dissolved in the decontamination waste liquid circulation line L11 and removed from the decontamination object 11 of the reactor facility.

  The 2nd chemical | medical agent supply part 22 is connected with the decontamination waste liquid circulation line L11 by the 2nd chemical | medical agent supply line L13. The second drug supply line L13 is a line for sending the second drug 27 containing the reducing agent from the second drug supply unit 22 to the decontamination waste liquid circulation line L11. The second chemical supply unit 22 supplies the second chemical 27 to the decontamination waste liquid circulation line L11 through the second chemical supply line L13. The second medicine supply line L13 is provided with a control valve V12 in the middle of the second medicine supply line L13. The supply amount of the second medicine 27 is adjusted by the control valve V12.

As the second drug 27, an organic acid or the like that has a reducing action and is chelate-bonded to a metal ion is used. Examples of the second drug 27 include oxalic acid (H ₂ C ₂ O ₄ ), citric acid (C ₆ H ₈ O ₇₄ ), nitric hydrofluoric acid mixed solution, oxalic acid and citric acid, or oxalic acid and picolinic acid. Any one or more of these are used. The second drug 27 is supplied from the second drug supply unit 22 through the second drug supply line L13 to the decontamination waste liquid circulation line L11. The second chemical 27 includes iron (Fe) -based oxides, nickel (Ni) -based oxides, etc. adhering to members such as reactor equipment and various pipes constituting the decontamination object 11 of the reactor facility. Dissolve in 2 drugs 27. Moreover, Cr oxide and unreacted permanganic acid are reduced. As a density | concentration of the 2nd chemical | medical agent 27, 0.005 mass% or more and 0.5 mass% or less are preferable, More preferably, 0.01 mass% or more and 0.3 mass% or less, More preferably, 0.01 mass% or more 0 .2% by mass or less.

  By supplying the second chemical 27 to the decontamination waste liquid circulation line L11, Fe oxide, Ni oxide, etc. contained in the deposits adhering to the decontamination object 11 of the nuclear reactor facility are contained in the decontamination waste liquid circulation line L11. And is removed from the decontamination target 11 of the reactor facility, and the decontamination target 11 of the reactor facility is decontaminated. Moreover, Cr oxide and unreacted permanganic acid are reduced.

  The 3rd chemical | medical agent supply part 23 is connected with the decontamination waste liquid circulation line L11 by the 3rd chemical | medical agent supply line L14. The 3rd chemical | medical agent supply line L14 is a line for sending the 3rd chemical | medical agent 28 containing the chemical | medical agent which decomposes | disassembles an oxidizing agent from the 3rd chemical | medical agent supply part 23 to the decontamination waste liquid circulation line L11. The third medicine supply unit 23 supplies the third medicine 28 to the decontamination waste liquid circulation line L11 through the third medicine supply line L14. The third medicine supply line L14 is provided with a control valve V13 in the middle of the third medicine supply line L14. The supply amount of the third medicine 28 is adjusted by the control valve V13.

As the third drug 28, for example, one containing at least one of the reducing agent, hydrazine, hydrogen peroxide (H ₂ O ₂ ), oxalic acid and the like is used. As the reducing agent, hydrazine, hydrogen peroxide (H ₂ O ₂ ), oxalic acid and the like, conventionally known ones are used, and the concentration thereof is appropriately adjusted. The third drug 28 is supplied from the third drug supply unit 23 through the third drug supply line L14 to the decontamination waste liquid circulation line L11. The third drug 28 decomposes the oxidizing agent.

  By supplying the 3rd chemical | medical agent 28 to the decontamination waste liquid circulation line L11, an oxidizing agent is decomposed | disassembled and an excess oxidizing agent is removed.

  The 4th chemical | medical agent supply part 24 is connected with the decontamination waste liquid circulation line L11 by the 4th chemical | medical agent supply line L15. The fourth chemical supply line L15 is a line for sending the fourth chemical 29 containing hydrogen peroxide from the fourth chemical supply unit 24 to the decontamination waste liquid circulation line L11. The fourth medicine supply unit 24 supplies the fourth medicine 29 to the decontamination waste liquid circulation line L11 through the fourth medicine supply line L15. The fourth medicine supply line L15 is provided with a control valve V14 in the middle of the fourth medicine supply line L15. The supply amount of the fourth medicine 29 is adjusted by the control valve V14.

As the fourth agent 29, for example, one containing hydrogen peroxide (H ₂ O ₂ ) or the like is used. As the hydrogen peroxide (H ₂ O ₂ ), a conventionally known one is used, and its concentration is appropriately adjusted. The fourth drug 29 is supplied from the fourth drug supply unit 24 through the fourth drug supply line L15 to the decontamination waste liquid circulation line L11. The fourth drug 29 decomposes the reducing agent.

In this embodiment, the fourth agent 29 such as hydrogen peroxide (H ₂ O ₂ ) is used to decompose the reducing agent, but the method for decomposing the reducing agent is not limited to this. Examples thereof include a method in which the decontamination waste liquid 14 is heated to thermally decompose the reducing agent, and a method in which the decontamination waste liquid 14 is irradiated with plasma to decompose the reducing agent.

  By supplying the 4th chemical | medical agent 29 to the decontamination waste liquid circulation line L11, a reducing agent is decomposed | disassembled and an excess reducing agent is removed.

  The 1st chemical | medical agent 26 and the 2nd chemical | medical agent 27 are the chemical | medical agents which melt | dissolve a deposit | attachment according to the kind of membrane | film | coat adhering to members, such as the reactor equipment and various piping which comprise the decontamination target object 11 of a nuclear reactor installation. They can be used in appropriate combinations.

  The number of times that the decontamination waste liquid 14 is circulated to the decontamination waste liquid circulation line L11 may be one time or a plurality of times.

  In addition, since the decontamination waste liquid 14 reduces the amount of the first chemical 26, the second chemical 27, the third chemical 28, and the fourth chemical 29, the first chemical 26 is contained in the decontamination target 11 of the reactor facility. , The second medicine 27, the third medicine 28, and the fourth medicine 29 can be sufficiently supplied from the medicine supply unit 12 to the decontamination waste liquid 14 from the first medicine 26, the second medicine 27, the third medicine 28, and the fourth. You may make it supply the chemical | medical agent 29 suitably.

  The 1st chemical | medical agent 26 supplied to the decontamination waste liquid circulation line L11 circulates through the decontamination waste liquid circulation line L11 as the decontamination waste liquid 14a, after passing the decontamination target object 11 of a nuclear reactor installation. Then, all or a part of the decontamination waste liquid 14a is extracted from the decontamination waste liquid circulation line L11, supplied to the waste liquid treatment system 13, and then returned to the decontamination waste liquid circulation line L11 to be decontaminated by the reactor equipment. The product 11 is supplied again. Similarly, the 2nd chemical | medical agent 27 supplied to the decontamination waste liquid circulation line L11 circulates through the decontamination waste liquid circulation line L11 as the decontamination waste liquid 14b, after passing the decontamination target object 11 of a nuclear reactor installation. Then, all or a part of the decontamination waste liquid 14b is extracted from the decontamination waste liquid circulation line L11 and supplied to the waste liquid treatment system 13. The third chemical 28 supplied to the decontamination waste liquid circulation line L11 circulates in the decontamination waste liquid circulation line L11 as the decontamination waste liquid 14c after passing through the decontamination target 11 of the reactor facility. Then, all or a part of the decontamination waste liquid 14c is extracted from the decontamination waste liquid circulation line L11 and supplied to the waste liquid treatment system 13. The fourth chemical 29 supplied to the decontamination waste liquid circulation line L11 circulates in the decontamination waste liquid circulation line L11 as the decontamination waste liquid 14d after passing through the decontamination target 11 of the reactor facility. Then, all or a part of the decontamination waste liquid 14d is extracted from the decontamination waste liquid circulation line L11 and supplied to the waste liquid treatment system 13.

  In this embodiment, the decontamination waste liquid 14a, the decontamination waste liquid 14b, the decontamination waste liquid 14c, and the decontamination waste liquid 14d may be collectively referred to as the decontamination waste liquid 14.

(Waste liquid treatment system)
The waste liquid treatment system 13 includes a filter (separation unit) 31, a first adsorption tower (first adsorption unit) 32, a second adsorption tower (fourth adsorption unit) 33, and a third adsorption tower (second adsorption unit). 34, a fourth adsorption tower (second adsorption section) 35, a fifth adsorption tower (third adsorption section) 36, a decontamination waste liquid treatment line L21, a first bypass line L22, and a second bypass line L23, Is provided.

  The decontamination waste liquid treatment line L21 is a line for extracting all or a part of the decontamination waste liquid 14 used in the decontamination target 11 of the reactor facility and circulating it to the decontamination target 11 of the reactor facility. The decontamination waste liquid 14 is a waste liquid generated when the first chemical 26, the second chemical 27, the third chemical 28, or the fourth chemical 29 passes through the decontamination target 11 of the nuclear reactor equipment. The waste liquid is any one of the waste liquid 14a, the decontamination waste liquid 14b, the decontamination waste liquid 14c, and the decontamination waste liquid 14d.

  The decontamination waste liquid processing line L21 includes decontamination waste liquid processing lines L21-1, L21-2, L21-3, L21-4, L21-5, and L21-6. The decontamination waste liquid treatment line L21-1 has one end connected to the decontamination waste liquid circulation line L11 and the other end connected to the filter 31. The decontamination waste liquid processing line L21-2 has one end connected to the filter 31 and the other end connected to the first adsorption tower 32. The decontamination waste liquid treatment line L21-3 has one end connected to the first adsorption tower 32 and the other end connected to the second adsorption tower 33. The decontamination waste liquid processing line L21-4 has one end connected to the second adsorption tower 33 and the other end connected to the third adsorption tower 34. The decontamination waste liquid processing line L21-5 has one end connected to the third adsorption tower 34 and the other end connected to the fourth adsorption tower 35. The decontamination waste liquid treatment line L21-6 has one end connected to the fourth adsorption tower 35 and the other end connected to the decontamination waste liquid circulation line L11.

  The decontamination waste liquid treatment line L21-1 is provided with a control valve V21 between the decontamination waste liquid circulation line L11 and the filter 31, and the decontamination waste liquid treatment line L21-2 is connected to the second bypass line L23. A control valve V <b> 22 is provided between the first adsorption tower 32. In the decontamination waste liquid treatment line L21-3, a control valve V23 is provided between the connection portion with the first bypass line L22 and the second adsorption tower 33. The decontamination waste liquid processing line L21-4 is provided with a control valve V24 in the middle of the decontamination waste liquid processing line L21-4. The decontamination waste liquid processing line L21-5 is provided with a control valve V25 in the middle of the decontamination waste liquid processing line L21-5. In the decontamination waste liquid treatment line L21-6, a control valve V26 is provided between the fourth adsorption tower 35 and a connection portion between the first bypass line L22 and the second bypass line L23. The flow rates of the respective decontamination waste liquids 14 passing through the decontamination waste liquid treatment lines L21-1 to L21-6 are adjusted by the control valves V21 to V26, respectively.

  The first bypass line L22 is a line provided to bypass the second adsorption tower 33, the third adsorption tower 34, and the fourth adsorption tower 35 of the decontamination waste liquid treatment line L21. One end of the first bypass line L22 is connected between the first adsorption tower 32 and the second adsorption tower 33 of the decontamination waste liquid treatment line L21, and the other end is removed from the control valve V26 of the decontamination waste liquid treatment line L21. It is connected to the downstream side in the flow direction of the dye waste liquid 14.

  The first bypass line L22 is provided with a control valve V31 in the middle of the first bypass line L22. The flow rate of the decontamination waste liquid 14 passing through the first bypass line L22 is adjusted by the control valve V31.

  The second bypass line L23 is a line provided to bypass the first adsorption tower 32, the second adsorption tower 33, the third adsorption tower 34, and the fourth adsorption tower 35 of the decontamination waste liquid treatment line L21. The second bypass line L23 includes second bypass lines L23-1 and L23-2. One end of the second bypass line L23-1 is connected to the upstream side in the flow direction of the decontamination waste liquid 14 from the control valve V22 of the decontamination waste liquid treatment line L21, and the other end is connected to the fifth adsorption tower 36. . The second bypass line L23-2 has one end connected to the fifth adsorption tower 36 and the other end connected to a connection portion of the decontamination waste liquid treatment line L21-6 with the first bypass line L22.

  The second bypass line L23-1 is provided with a regulating valve V32 in the middle of the second bypass line L23-1. The second bypass line L23-2 is provided with a control valve V33 in the middle of the second bypass line L23-2. The flow rates of the decontamination waste liquid 14 passing through the second bypass lines L23-1 and L23-2 are adjusted by the control valves V32 and V33, respectively.

  The filter 31 is provided on the upstream side of the connection portion of the decontamination waste liquid treatment line L21-2 with the second bypass line L23-1. The filter 31 removes deposits in the decontamination waste liquid 14. As the filter 31, for example, poremet is used. Thereby, even when the decontamination waste liquid 14 contains the deposit, it can suppress that a deposit is supplied to the 1st adsorption tower 32. FIG. In particular, when the reducing agent is decomposed, metal ions such as Fe ions, Ni ions, and Cr ions that are present in the decontamination solution are precipitated as hydroxides, so that the filter 31 is disposed upstream of the first adsorption tower 32. By recovering the precipitate generated in the decontamination solution, deterioration of the first adsorption tower 32 and the like can be reduced.

  The first adsorption tower 32 includes a first resin 41 inside the first adsorption tower 32. The first resin 41 adsorbs the metal ions dissolved from the oxide film present in the decontamination target 11 of the reactor facility or the chelate compound contained in the decontamination waste liquid 14. A chelate compound is formed by a metal ion dissolved from an oxide film and a chelate bond with an organic acid. The first resin 41 mainly adsorbs metal ions dissolved from the oxide film present in the decontamination object 11 of the reactor facility, but the chelate compound has the metal ions dissolved from the oxide film chelated to the organic acid. Since it is a compound, a chelate compound can also be adsorbed.

  The first resin 41 includes at least one of a cationic resin and an inorganic adsorbent (inorganic ion exchanger). Examples of the inorganic ion exchanger include zeolite, zirconium phosphate, clay mineral, and non-zeolite inorganic ion exchanger. The inorganic ion exchanger is appropriately selected according to the type of metal ion to be removed. Among these, it is preferable to use zeolite as the inorganic ion exchanger. Since zeolite is an inorganic substance, hydrogen gas is not generated by radioactive decomposition unlike organic substances. Therefore, even if zeolite adsorbs a radioactive substance and becomes a high dose, it can be buried in a disposal site by solidifying the zeolite into a solid substance.

  As for the 1st adsorption tower 32, the circumference of the 1st adsorption tower 32 is covered with shielding board 37-1. As will be described later, the first resin 41 has a high dose because the metal ions dissolved from the oxide film are adsorbed. Therefore, it is possible to prevent radiation from leaking to the outside of the first resin 41 by covering the periphery of the first adsorption tower 32 with the shielding plate 37-1.

  The second adsorption tower 33 includes a fourth resin 42. The fourth resin 42 adsorbs the chelate compound contained in the decontamination waste liquid 14. The fourth resin 42 includes at least one of an anion resin, a mixed bed resin in which the cation resin and the anion resin are mixed, and a mixture of the anion resin and the mixed bed resin.

  Moreover, the 2nd adsorption tower 33 is covered with the shielding board 37-2 similarly to the 1st adsorption tower 32. FIG. As will be described later, the fourth resin 42 has a high dose because the chelate compound is adsorbed. Therefore, it is possible to prevent radiation from leaking to the outside of the fourth resin 42 by covering the periphery of the second adsorption tower 33 with the shielding plate 37-2.

  The third adsorption tower 34 includes a second resin 43A. The second resin 43A adsorbs the organic acid contained in the decontamination waste liquid 14. The second resin 43A includes at least one of an anion resin, a mixed bed resin in which the cation resin and the anion resin are mixed, and a mixture of the anion resin and the mixed bed resin.

  The fourth adsorption tower 35 includes a second resin 43B. The second resin 43B adsorbs the organic acid contained in the decontamination waste liquid 14 like the second resin 43A. The second resin 43B includes at least one of an anion resin, a mixed bed resin in which the cation resin and the anion resin are mixed, and a mixture of the anion resin and the mixed bed resin.

  The fifth adsorption tower 36 includes a third resin 44. The third resin 44 adsorbs the metal ions of the oxidant contained in the decontamination waste liquid 14. The third resin 44 includes at least one of a cationic resin and an inorganic adsorbent.

  All or part of the decontamination waste liquid 14 circulating through the decontamination waste liquid circulation line L11 passes through any one of the decontamination waste liquid treatment line L21, the first bypass line L22, and the second bypass line L23, and is again removed. It returns to the dye waste liquid circulation line L11. The decontamination waste liquid 14 circulates between the decontamination waste liquid circulation line L11 and the waste liquid treatment system 13. The number of times that the decontamination waste liquid 14 is circulated through the decontamination waste liquid circulation line L11 and the waste liquid treatment system 13 may be one time or multiple times.

  The waste liquid treatment system 13 includes a first adsorption tower 32, a second adsorption tower 33, a third adsorption tower 34, a fourth adsorption tower 35, a fifth adsorption tower 36, a decontamination waste liquid treatment line L21, 1 bypass line L22 and 2nd bypass line L23 are provided. The decontamination waste liquid 14 produced by decontaminating members such as reactor equipment and various pipes constituting the decontamination object 11 of the nuclear reactor facility contains a radioactive substance. The radioactive material of the decontamination waste liquid 14 is adsorbed by the first resin 41, the fourth resin 42, the second resins 43A and 43B, and the third resin 44. Therefore, the first resin 41, the fourth resin 42, the second resins 43A and 43B, and the third resin 44 become radioactive waste contaminated with radioactive substances. The decontamination waste liquid 14a to which the oxidizing agent is added contains metal ions dissolved from the oxide film. The decontamination waste liquid 14c in which the third chemical 28 is added and the oxidizing agent is decomposed contains the metal ions of the oxidizing agent. Since the metal ions dissolved from the oxide film and the metal ions of the oxidizing agent are cations, they are adsorbed by the first resin 41 and the third resin 44 including at least a cationic resin or an inorganic adsorbent. As will be described later, metal ions dissolved from the oxide film are adsorbed on the first resin 41. As will be described later, the third resin 44 adsorbs metal ions of the oxidizing agent. Here, the first resin 41 or the third resin 44 can adsorb both the metal ions dissolved from the oxide film and the metal ions of the oxidizing agent. However, in this case, since the dose of the first resin 41 or the third resin 44 becomes high, the first resin 41 or the third resin 44 cannot be disposed of by incineration, and a high-dose used that is difficult to be buried is used. The generation amount of the first resin 41 or the third resin 44 is increased. In particular, conventionally, a reducing agent is added to a decontamination waste liquid containing metal ions contained in an oxidizing agent, and then adsorbed on an ion exchange resin. In addition, the metal ions dissolved from the oxide film to be decontaminated after the addition of the reducing agent and the metal ions of the oxidizing agent are adsorbed on the ion exchange resin, and a large amount of ion exchange resin that can be handled at a high dose. Has occurred. Conventionally, the adsorption selectivity between the chelate compound and the organic acid is not taken into consideration, and therefore it is necessary to prepare an excessive amount of ion exchange resins such as the fourth resin 42 and the second resins 43A and 43B. Therefore, a large amount of high-dose ion exchange resin that is difficult to be buried is generated.

  On the other hand, in the waste liquid treatment system 13, the metal ions of the oxidant remaining in the decontamination waste liquid 14c after decomposing the oxidant with a chemical are adsorbed to the third resin 44, and the metal ions dissolved from the oxide film are the first resin. 41 is adsorbed. Since the cation dissolved from the oxide film has a high dose, the dose of the first resin 41 increases. However, the metal ion of the oxidant remaining in the decontamination waste liquid 14c after decomposing the oxidant with a chemical agent has a low dose, so the third resin 44 has a low dose. Therefore, since the third resin 44 can be incinerated, the first resin 41 is stored as a high-dose secondary waste that is difficult to be buried, and the third resin 44 is incinerated to reduce the volume. Can do.

  In addition, the waste liquid treatment system 13 uses the first resin 41, the fourth resin 42, and the second resins 43A and 43B in the flow direction of the decontamination waste liquid 14, and the first resin 41, the fourth resin 42, and the second resins 43A and 43B. Arranged in the order of. The fourth resin 42 and the second resins 43A and 43B include at least an anion resin. The decontamination waste liquid 14d obtained by decomposing the reducing agent contains a chelate compound and an organic acid. Since the chelate compound and the organic acid are anions, the chelate compound or the organic acid contained in the decontamination waste liquid 14d is adsorbed to at least the fourth resin 42 and the second resins 43A and 43B containing the anion resin. Since the chelate compound has higher adsorption selectivity than the organic acid, the chelate compound can be adsorbed by the fourth resin 42 and the organic acid can be adsorbed by the second resins 43A and 43B. The chelate compound has a high dose because it is a metal ion dissolved from the radioactive clad and an organic acid. A chelate compound having a high dose is adsorbed by the fourth resin 42, and an organic acid having a low dose is adsorbed by the second resins 43A and 43B, so that the dose of the fourth resin 42 is increased, but the second resin 43A and 43B The dose can be low. Therefore, since the second resins 43A and 43B can be incinerated, the second resin 43A and 43B is incinerated and reduced in volume as a high-dose secondary waste in which only the fourth resin 42 is difficult to be buried. Can be In addition, chelate compounds are likely to promote nuclide migration and reduce the barrier performance of the disposal site, so the anion resin cannot be buried and must be stored in a nuclear power plant. In the waste liquid treatment system 13, the fourth resin 42 mainly adsorbs the chelate compound due to the difference in the adsorption selectivity of the chelate compound and the organic acid to the ion adsorbent. Therefore, the waste liquid treatment system 13 can reduce the amount of secondary waste of ion exchange resin containing a chelate compound that must be stored in a nuclear power plant.

  Therefore, the waste liquid treatment system 13 adsorbs to different ion adsorbents according to metals having different doses, and uses the difference in adsorption selectivity between the chelate compound and the organic acid to the ion adsorbent to perform ion adsorption. The agent is arranged. If the waste liquid treatment system 13 is used, the first resin 41 and the fourth resin 42 are stored as secondary waste in the nuclear power plant, and the second resins 43A and 43B and the third resin 44 are incinerated to reduce the volume. Therefore, by processing the decontamination waste liquid 14, the amount of high-dose secondary waste that is difficult to be buried can be reduced.

<Method of treating decontamination waste liquid>
Next, a decontamination method to which the decontamination waste liquid treatment method using the waste liquid treatment system 13 is applied will be described. The treatment method of the decontamination waste liquid includes the following steps. After supplying the oxidant to the decontamination waste liquid, it starts from the oxidant purification process or the reduction process. It includes at least once in the order of the process, the reduction process, and the purification process, and ends with the purification process. In the oxidizing agent purification step, the reduction step, and the purification step, all or part of the decontamination waste liquid 14 is passed through the decontamination waste liquid treatment line L21, the first bypass line L22, or the second bypass line L23, and then the decontamination waste liquid. It returns to the circulation line L11, and it circulates between the decontamination target object 11 and the waste liquid processing system 13 of a nuclear reactor once or more.
(A) After adding the 1st chemical | medical agent 26 to the decontamination waste liquid circulation line L11, the 3rd chemical | medical agent 28 is added, all or a part of the decontamination waste liquid 14c containing the 3rd chemical | medical agent 28 is supplied to the 2nd bypass line L23. After passing through the fifth adsorption tower 36, it is returned to the decontamination waste liquid circulation line L11 and supplied to the decontamination object 11 of the nuclear reactor equipment (b) The decontamination waste liquid circulation line L11 After the two chemicals 27 are added, all or a part of the decontamination waste liquid 14b containing the second chemical 27 is passed through the first adsorption tower 32 through the decontamination waste liquid treatment line L21-2, and the first bypass line L22. Is returned to the decontamination waste liquid circulation line L11 and supplied to the decontamination object 11 of the reactor facility (c) The fourth chemical 29 is added to the decontamination waste liquid 14b, and the decontamination waste liquid 14b is added. After decomposing the reducing agent contained, All or part of the decontaminated decontamination waste liquid 14d passes through the first adsorption tower 32, the second adsorption tower 33, the third adsorption tower 34, and the fourth adsorption tower 35, and then enters the decontamination waste liquid circulation line L11. Purification process for returning to the decontamination object 11 of the reactor facility

(Decontamination method)
FIG. 2 is a flowchart illustrating an example of a procedure of a decontamination method to which the processing method of the decontamination waste liquid according to the present embodiment is applied, and FIG. 3 illustrates a state in an oxidant supply process in which an oxidant is added. FIG. 4 is an explanatory view showing a state in the oxidant purification step, FIG. 5 is an explanatory view showing a state in the reduction step, and FIG. 6 is an explanatory view showing a state in the purification step. is there. In addition, the thick line in FIGS. 4-6 shows the flow of the decontamination waste liquid 14 in each process.

  As shown in FIG. 3, the 1st chemical | medical agent 26 is supplied to the decontamination waste liquid circulation line L11, and an oxidizing agent is supplied to the decontamination target object 11 of a nuclear reactor installation (1st oxidizing agent supply process: step S11). Thereby, Cr oxide contained in the deposit | attachment adhering to the decontamination target object 11 of a nuclear reactor installation is removed, and the decontamination waste liquid 14a is made to circulate to the decontamination waste liquid circulation line L11.

  Next, as shown in FIG. 4, the 3rd chemical | medical agent 28 is supplied to the decontamination waste liquid circulation line L11, the oxidizing agent contained in the decontamination waste liquid 14a (refer FIG. 3) is decomposed | disassembled, and it is set as the decontamination waste liquid 14c. After the decontamination waste liquid 14c is circulated once or more in the decontamination waste liquid circulation line L11, all or a part of the decontamination waste liquid 14c is sent from the decontamination waste liquid circulation line L11 to the decontamination waste liquid treatment line L21-2. The decontamination waste liquid 14c is passed through the second bypass line L23, passed through the fifth adsorption tower 36, then returned to the decontamination waste liquid circulation line L11 through the decontamination waste liquid treatment line L21-6, and the reactor equipment. To the decontamination target 11 (first oxidant purification step: step S12). When the decontamination waste liquid 14 c passes through the fifth adsorption tower 36, at least the metal ions of the oxidizing agent contained in the decontamination waste liquid 14 c are adsorbed by the fifth adsorption tower 36. As a result, at least metal ions of the oxidizing agent are removed from the decontamination waste liquid 14c. Thereafter, the decontamination waste liquid 14c that has passed through the fifth adsorption tower 36 is returned from the second bypass line L23 to the decontamination waste liquid circulation line L11 through the decontamination waste liquid treatment line L21-6.

  The decontamination waste liquid 14c is circulated to the decontamination waste liquid circulation line L11 through the decontamination waste liquid treatment lines L21-1, L21-2, the second bypass lines L23-1, L23-2, and the decontamination waste liquid treatment line L21-6. The cycle is performed at least once.

  Next, as shown in FIG. 5, the 2nd chemical | medical agent 27 is added to the decontamination waste liquid circulation line L11, and it is set as the decontamination waste liquid 14b. After the decontamination waste liquid 14b is circulated at least once in the decontamination waste liquid circulation line L11, all or part of the decontamination waste liquid 14b is sent from the decontamination waste liquid circulation line L11 to the decontamination waste liquid treatment line L21-2. After passing through the first adsorption tower 32, the decontamination waste liquid 14b is sent from the decontamination waste liquid processing line L21-3 to the first bypass line L22, and is supplied to the decontamination waste liquid processing line L21-6. The decontamination waste liquid 14b is returned to the decontamination waste liquid circulation line L11 through the decontamination waste liquid treatment line L21-6, and is supplied to the decontamination target 11 of the reactor facility (first reduction process: step S13). When the decontamination waste liquid 14b passes through the first adsorption tower 32, metal ions dissolved from the oxide film in the decontamination waste liquid 14b are adsorbed to at least the first resin 41. Thereby, the metal ions dissolved from the oxide film are at least removed from the decontamination waste liquid 14b. Thereafter, the decontamination waste liquid 14b that has passed through the first adsorption tower 32 is returned from the first bypass line L22 to the decontamination waste liquid circulation line L11 through the decontamination waste liquid treatment line L21-6.

  The cycle for circulating the decontamination waste liquid 14b through the decontamination waste liquid treatment lines L21-1, L21-2, the first bypass line L22, the decontamination waste liquid treatment line L21-6 to the decontamination waste liquid circulation line L11 is at least once. This is done.

  Next, as shown in FIG. 6, the 4th chemical | medical agent 29 is added to the decontamination waste liquid circulation line L11, the reducing agent contained in the decontamination waste liquid 14b (refer FIG. 5) is decomposed | disassembled, and it is set as the decontamination waste liquid 14d. After the decontamination waste liquid 14d is circulated at least once in the decontamination waste liquid circulation line L11, all or part of the decontamination waste liquid 14d is sent from the decontamination waste liquid circulation line L11 to the decontamination waste liquid treatment line L21-2. The decontamination waste liquid 14d passes through the first adsorption tower 32 and is then sent to the second adsorption tower 33 from the decontamination waste liquid treatment line L21-3. Thereafter, the decontamination waste liquid 14d passes through the second adsorption tower 33 and is then sent to the third adsorption tower 34 from the decontamination waste liquid treatment line L21-4. Thereafter, the decontamination waste liquid 14d passes through the third adsorption tower 34, and is then sent from the decontamination waste liquid treatment line L21-5 to the fourth adsorption tower 35. Thereafter, the decontamination waste liquid 14d passes through the fourth adsorption tower 35 and is then supplied from the decontamination waste liquid treatment line L21-6 to the decontamination waste liquid circulation line L11 (first purification step: step S14). When the decontamination waste liquid 14d passes through the first adsorption tower 32 and the second adsorption tower 33, the chelate compound of the decontamination waste liquid 14d is adsorbed by at least the first resin 41 and the fourth resin 42. Thereby, the chelate compound is removed from at least the decontamination waste liquid 14d.

  Thereafter, when the decontamination waste liquid 14d that has passed through the second adsorption tower 33 passes through the third adsorption tower 34 and the fourth adsorption tower 35, the organic acid of the decontamination waste liquid 14d is adsorbed to at least the second resins 43A and 43B. Is done. As a result, at least the organic acid is removed from the decontamination waste liquid 14d.

  Thereafter, the decontamination waste liquid 14d is returned to the decontamination waste liquid circulation line L11 through the decontamination waste liquid treatment line L21-6.

  The cycle for circulating the decontamination waste liquid 14d through the decontamination waste liquid treatment lines L21-1 to L21-6 to the decontamination waste liquid circulation line L11 is performed at least once.

  Next, as shown in FIG. 3, the 1st chemical | medical agent 26 is supplied to the decontamination waste liquid circulation line L11, an oxidizing agent is supplied to the decontamination target object 11 of a nuclear reactor equipment, and the decontamination waste liquid 14a is circulated through the decontamination waste liquid. Circulate in line L11 (second oxidant supply step: step S15). Since the second oxidant supply step (step S15) is the same process as the first oxidant supply step (step S11), description thereof is omitted.

  Then, as shown in FIG. 4, the 3rd chemical | medical agent 28 is supplied to the decontamination waste liquid circulation line L11, the oxidizing agent contained in the decontamination waste liquid 14a (refer FIG. 3) is decomposed | disassembled, and it is set as the decontamination waste liquid 14c. After the decontamination waste liquid 14c is circulated once or more in the decontamination waste liquid circulation line L11, all or a part of the decontamination waste liquid 14c is sent from the decontamination waste liquid circulation line L11 to the decontamination waste liquid treatment line L21-2. Then, the dye waste liquid 44c is passed through the second bypass line L23, passed through the fifth adsorption tower 36, and then returned to the decontamination waste liquid circulation line L11 through the decontamination waste liquid treatment line L21-6. To the decontamination object 11 (second oxidant purification step: step S16). Since the second oxidant purification step (step S16) is the same process as the first oxidant purification step (step S12), description thereof is omitted.

  Next, as shown in FIG. 5, the 2nd chemical | medical agent 27 is added to the decontamination waste liquid circulation line L11, and it is set as the decontamination waste liquid 14b. After the decontamination waste liquid 14b is circulated one or more times in the decontamination waste liquid circulation line L11, all or a part of the decontamination waste liquid 14b is decontaminated from the decontamination waste liquid circulation line L11 to the decontamination waste liquid treatment lines L21-1, L21-2. Sent to. After passing through the first adsorption tower 32, the decontamination waste liquid 14b is sent from the decontamination waste liquid processing line L21-3 to the first bypass line L22, and is supplied to the decontamination waste liquid processing line L21-6. The decontamination waste liquid 14b is returned to the decontamination waste liquid circulation line L11 through the decontamination waste liquid treatment line L21-6, and is supplied to the decontamination target 11 of the reactor facility (second reduction process: step S17). Since the second reduction process (step S17) is the same process as the first reduction process (step S13), description thereof is omitted.

  Next, as shown in FIG. 6, the 4th chemical | medical agent 29 is added to the decontamination waste liquid circulation line L11, the reducing agent contained in the decontamination waste liquid 14b (refer FIG. 5) is decomposed | disassembled, and it is set as the decontamination waste liquid 14d. After the decontamination waste liquid 14d is circulated at least once in the decontamination waste liquid circulation line L11, all or part of the decontamination waste liquid 14d is decontaminated waste liquid treatment lines L21-1, L21-2 from the decontamination waste liquid circulation line L11. And then sent to the first adsorption tower 32. The decontamination waste liquid 14d is transferred to the first adsorption tower 32, the second adsorption tower 33, the third adsorption tower 34, the fourth adsorption tower 35, the first adsorption tower 32, the second adsorption tower 33, the third adsorption tower 34, and the second adsorption tower 34. It passes in order of 4 adsorption towers 35. The decontamination waste liquid 14d passes through the fourth adsorption tower 35, then returns to the decontamination waste liquid circulation line L11 through the decontamination waste liquid treatment line L21-6, and is supplied to the decontamination target 11 of the reactor facility. (Second purification step: Step S14). Since the second purification process (step S18) is the same process as the first purification process (step S14), description thereof is omitted.

  As described above, the treatment method of the decontamination waste liquid according to the present embodiment adsorbs different ion adsorbents according to cations having different doses, and adsorbs chelate compounds and organic acids to the ion adsorbent. By utilizing the difference in selectivity, the chelate compound and the organic acid are adsorbed on the ion adsorbent. The metal ions of the oxidant remaining in the decontamination waste liquid 14c after decomposing the oxidant with the chemical are adsorbed on the third resin 44, and the metal ions dissolved from the oxide film are adsorbed on the first resin 41. Since the cation dissolved from the oxide film has a high dose, the dose of the first resin 41 increases. However, the metal ion of the oxidant remaining in the decontamination waste liquid 14c after decomposing the oxidant with a chemical agent has a low dose, so the third resin 44 has a low dose. Therefore, since the third resin 44 can be incinerated, the third resin 44 can be incinerated and reduced in volume as a high-dose secondary waste in which only the first resin 41 is difficult to be buried. it can.

  Further, the first resin 41, the fourth resin 42, and the second resins 43A and 43B are arranged in the order of the first resin 41, the fourth resin 42, and the second resins 43A and 43B in the flow direction of the decontamination waste liquid 14. . The fourth resin 42 and the second resins 43A and 43B include at least an anion resin. Since the chelate compound and the organic acid are anions and the chelate compound has higher adsorption selectivity than the organic acid, the chelate compound is adsorbed by the second adsorption tower 33, and the organic acid is adsorbed by the third adsorption tower 34 and the fourth adsorption tower 35. Can be absorbed. The chelate compound has a high dose because it is a metal ion dissolved from the radioactive clad and an organic acid. Therefore, a chelate compound having a high dose is adsorbed by the second adsorption tower 33, and an organic acid having a low dose is adsorbed by the third adsorption tower 34 and the fourth adsorption tower 35. Thereby, although the dose of the 4th resin 42 becomes high, the dose of the 2nd resins 43A and 43B can be made low. Therefore, since the second resins 43A and 43B can be incinerated, the second resin 43A and 43B is incinerated and reduced in volume as a high-dose secondary waste in which only the fourth resin 42 is difficult to be buried. Can be

  Therefore, if the processing method of the decontamination waste liquid which concerns on a present Example is used, the 1st resin 41 and the 4th resin 42 will be buried as waste, and the 2nd resin 43A, 43B and the 3rd resin 44 will be incinerated. Since the volume can be reduced, by treating the decontamination waste liquid 14, it is possible to reduce the amount of high-dose used ion adsorbent that is difficult to be buried as secondary waste.

  Further, in the decontamination method to which the decontamination waste liquid treatment method according to the present embodiment shown in FIG. 2 is applied, the process starts from the first oxidant purification step (step S12). However, the present invention is not limited to this. You may start from 1 reduction | restoration process (step S13).

  In the decontamination method to which the decontamination waste liquid treatment method according to the present embodiment is applied, the oxidant purification step and the reduction step are performed in two cycles in the order of the oxidant purification step and the reduction step. Instead, the oxidant purification step and the reduction step may be performed three or more cycles in the order of the oxidant purification step and the reduction step.

  In addition, this invention is not limited to the said Example, A various change is possible in the range which does not deviate from the meaning of invention. For example, in the present embodiment, the second adsorption tower 33 is used. However, the present invention is not limited to this. When the anion such as a chelate compound and an organic acid can be adsorbed only by the third adsorption tower 34, the second adsorption tower 33 is used. The two adsorption towers 33 may not be provided.

  In this embodiment, two types of second resin 43A and second resin 43B are used. However, the present invention is not limited to this, and one or both of the second resin 43A and the second resin 43B are further added. A plurality of them may be provided.

  In this embodiment, the filter 31 is provided on the upstream side in the flow direction of the decontamination waste liquid 14 with respect to the connection portion of the decontamination waste liquid treatment line L21-2 with the second bypass line L23-1. There is no limitation, and the filter 31 may not be provided if the decontamination waste liquid 14 does not contain precipitates and there is no particular problem such as damage to the first adsorption tower 32 or the like.

  In the present embodiment, the case of decontamination of piping and equipment installed in a nuclear power plant has been described. However, the present invention is not limited to this, and piping and equipment used for facilities that handle hazardous substances. The same can be used in the case of washing.

DESCRIPTION OF SYMBOLS 10 Decontamination system 11 Decontamination target object of nuclear reactor equipment 12 Chemical supply part 13 Waste liquid processing system 14, 14a, 14b, 14c, 14d Decontamination waste liquid 21 1st chemical | medical agent supply part 22 2nd chemical | medical agent supply part 23 3rd chemical | medical agent supply Unit 24 Fourth drug supply unit 26 First drug 27 Second drug 28 Third drug 29 Fourth drug 31 Filter (separation unit)
32 1st adsorption tower (1st adsorption part)
33 Second adsorption tower (fourth adsorption section)
34 3rd adsorption tower (2nd adsorption part)
35 Fourth adsorption tower (second adsorption part)
36 5th adsorption tower (3rd adsorption part)
37-1, 37-2 Shielding plate 41 1st resin 42 4th resin 43A 2nd resin 43B 2nd resin 44 3rd resin L11 Decontamination waste liquid circulation line L12 1st chemical | medical agent supply line L13 2nd chemical | medical agent supply line L14 3rd Drug supply line L15 Fourth drug supply line L21, L21-1, L21-2, L21-3, L21-4, L21-5, L21-6 Decontamination waste liquid treatment line L22 First bypass line L23, L23-1 L23-2 Second bypass line V11 to V14, V21 to V26, V31, V32, V33 Control valve

Claims (12)

A decontamination waste liquid treatment line for extracting the decontamination waste liquid generated from the chemical used in the decontamination target of the nuclear reactor equipment, and circulating it to the decontamination target of the nuclear reactor equipment;
Provided in the decontamination waste liquid treatment line, the metal ions dissolved from the oxide film present in the decontamination object of the reactor facility, or the metal ions dissolved from the oxide film contained in the decontamination waste liquid are organic acids and A first adsorbing portion comprising a first resin that adsorbs at least a chelate compound formed by chelate bonding;
One or more second adsorption units provided in the decontamination waste liquid treatment line, the second adsorption unit including a second resin that adsorbs at least the organic acid contained in the decontamination waste liquid;
A first bypass line provided to bypass the second adsorption part of the decontamination waste liquid treatment line;
A second bypass line provided to bypass the first adsorption unit and the second adsorption unit of the decontamination waste liquid treatment line;
A third adsorbing portion provided in the second bypass line, and comprising a third resin that adsorbs at least the metal ions of the oxidizing agent contained in the decontamination waste liquid;
A waste liquid treatment system comprising: In claim 1,
A waste liquid treatment comprising a fourth adsorbing portion provided between the first adsorbing portion and the second adsorbing portion of the decontamination waste liquid treatment line and comprising a fourth resin that at least adsorbs the chelate compound. system. In claim 1 or 2,
Waste liquid characterized by having a separation part that is provided upstream of the first adsorption part of the decontamination waste liquid treatment line in the flow direction of the decontamination waste liquid and removes precipitates contained in the decontamination waste liquid. Processing system. In any one of Claims 1 thru | or 3,
The first resin contains at least a cationic resin or an inorganic adsorbent,
The second resin includes at least one of an anion resin, a mixed bed resin in which a cation resin and an anion resin are mixed, and a resin in which the anion resin and the mixed bed resin are mixed,
The waste liquid treatment system, wherein the third resin contains at least a cationic resin or an inorganic adsorbent. In any one of claims 2 to 4,
The fourth resin includes at least one of an anion resin, a mixed bed resin in which a cation resin and an anion resin are mixed, and a resin in which the anion resin and the mixed bed resin are mixed. Waste liquid treatment system. A decontamination waste liquid circulation line that discharges the chemical supplied to the decontamination target of the nuclear reactor facility from the decontamination target of the nuclear reactor facility as a decontamination waste liquid, and circulates it to the decontamination target of the nuclear reactor facility,
A chemical supply section for supplying a chemical containing an oxidizing agent or a reducing agent to the decontamination waste liquid circulation line;
A waste liquid treatment system according to any one of claims 1 to 5,
The decontamination waste liquid treatment line is connected to the decontamination waste liquid circulation line. A decontamination waste liquid circulation line that discharges the chemical supplied to the decontamination target of the nuclear reactor facility from the decontamination target of the nuclear reactor facility as a decontamination waste liquid, and circulates it to the decontamination target of the nuclear reactor facility,
A chemical supply section for supplying a chemical containing an oxidizing agent or a reducing agent to the decontamination waste liquid circulation line;
A decontamination waste liquid treatment line connected to the decontamination waste liquid circulation line, extracting the decontamination waste liquid and circulating it to the decontamination object of the nuclear reactor facility;
Provided in the decontamination waste liquid treatment line, the metal ions dissolved from the oxide film present in the decontamination object of the reactor facility, or the metal ions dissolved from the oxide film contained in the decontamination waste liquid are organic acids and A first adsorbing portion comprising a first resin that adsorbs at least a chelate compound formed by chelate bonding;
One or more second adsorption units provided in the decontamination waste liquid treatment line, the second adsorption unit including a second resin that adsorbs at least the organic acid contained in the decontamination waste liquid;
A first bypass line provided to bypass the second adsorption part of the decontamination waste liquid treatment line;
A second bypass line provided to bypass the first adsorption unit and the second adsorption unit of the decontamination waste liquid treatment line;
A third adsorbing portion provided in the second bypass line, and comprising a third resin that adsorbs at least the metal ions of the oxidizing agent contained in the decontamination waste liquid;
A waste liquid treatment system having
An oxidizing agent supplying step of supplying an oxidizing agent to the decontamination waste liquid;
The decontamination waste liquid containing the agent for decomposing the oxidant is added, and the decontamination waste liquid containing the agent for decomposing the oxidant is allowed to pass through the second adsorption line and the third adsorption unit, and is contained in the decontamination waste liquid After at least adsorbing metal ions of the oxidant, an oxidant purification step of supplying the decontamination object of the nuclear reactor facility;
After adding a reducing agent to the decontamination waste liquid, the deionization waste liquid containing the reducing agent is allowed to pass through the first adsorption unit, and the metal ions dissolved from the oxide film present in the decontamination target of the reactor facility, Or after at least adsorbing the chelate compound, passing through the first bypass line and supplying to the decontamination object of the reactor facility,
After decomposing the reducing agent contained in the decontamination waste liquid, the decontamination waste liquid decomposing the reducing agent is passed through the first adsorption unit and the second adsorption unit to remove the reactor equipment. A purification step of supplying at least the chelate compound or organic acid contained in the object to be dyed to the object to be decontaminated in the reactor facility;
Including
Starting from the oxidant supply step or the reduction step,
Including the oxidant supply step, the oxidant purification step, the reduction step and the purification step at least once in the order of the oxidant supply step, the oxidant purification step, the reduction step and the purification step,
The waste liquid treatment method is characterized by ending with the purification step. In claim 7,
A waste liquid treatment comprising a fourth adsorbing portion provided between the first adsorbing portion and the second adsorbing portion of the decontamination waste liquid treatment line and comprising a fourth resin that at least adsorbs the chelate compound. Method. In claim 7 or 8,
A waste liquid treatment method, wherein deposits contained in the decontamination waste liquid are removed upstream of the first adsorption portion of the decontamination waste liquid treatment line in the flow direction of the decontamination waste liquid. In any one of claims 7 to 9,
The first resin contains at least a cationic resin or an inorganic adsorbent,
The second resin includes at least one of an anion resin, a mixed bed resin in which a cation resin and an anion resin are mixed, and a resin in which the anion resin and the mixed bed resin are mixed,
The waste liquid treatment method, wherein the third resin contains at least a cationic resin or an inorganic adsorbent. In any one of claims 7 to 10,
The fourth resin includes at least one of an anion resin, a mixed bed resin in which a cation resin and an anion resin are mixed, and a resin in which the anion resin and the mixed bed resin are mixed. Waste liquid treatment method. In any one of claims 7 to 11,
In the oxidizing agent purification step and the reduction step, the decontamination waste liquid is decontaminated from any one of the decontamination waste liquid circulation line, the first bypass line and the second bypass line, and the decontamination target of the nuclear reactor equipment. A waste liquid treatment method characterized by circulating at least once.

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