System and Method for Decontamination of Radioactive Spent Ion-Exchange Resin Using Ultrasonic Wave

Abstract

The present invention provides a radioactive waste resin decontamination treatment apparatus and method comprising: a pretreatment unit for coagulating and removing radionuclides by introducing water containing radioactive waste resin and a chemical containing a coagulant; a decontamination treatment unit for separating and removing radionuclides adsorbed or attached to the surface of the pretreated radioactive waste resin by applying acid treatment and ultrasound; a resin drying treatment unit for drying the decontaminated radioactive waste resin to separate it into waste resin and moisture, and then heating the separated resin to convert organic X4C adsorbed on the resin surface into inorganic X4CO2; and an X4C nuclide collection unit for adsorbing and removing gaseous X4C nuclides by heating the separated moisture.

Description

Technology Field

[0001] The present invention relates to an apparatus and method for the efficient removal of radionuclides adsorbed on the surface of trace-contaminated radioactive waste resin generated in nuclear power plants. More specifically, the invention relates to an apparatus and method for decontaminating radioactive waste resin contaminated with radioactive materials, which induces self-disposal by desorbing and separating radionuclides underwater using chemicals and ultrasound without emitting toxic gases, minimizes the amount of radioactive exhaust gas generated during desorption, and safely separates and removes desorbed ionic and particulate radioactive materials, thereby contributing significantly to reducing disposal costs, protecting the natural environment, and achieving carbon neutrality by reducing the amount of radioactive waste generated as well as reducing the emission of atmospheric pollutants and radioactive materials. Background Technology

[0002] In the reactor coolant used for power control in nuclear power plants, trace amounts of metallic substances contained in the water react with neutrons as they pass through the reactor, generating various radionuclides and particulate / ionic substances. Steam generators are used to convert the high heat generated during reactor operation into steam to rotate the turbine; however, during long-term operation, the heat exchangers that generate steam often experience minute leaks due to stress corrosion of the tube materials caused by the deterioration of the steam generator tubes. Unless the leakage of radioactive material through the steam generator (SG) tubes is assessed to be severe enough to affect the environment, the leaked radioactive material is removed through ion exchange resin towers and filtration filters until the completion of a single operation cycle for nuclear fuel replacement. Continuous operation is performed to maintain sustained power output until the nuclear fuel is replaced; by the time a cycle ends, a significant amount of radionuclides accumulate on the surface of the ion exchange resin in the form of ions or particles. The amount of used resin installed in the ion exchange resin towers of the steam generator blow-down system is approximately 10,000 L per unit per year on average. These used ion exchange resins contain trace amounts of γ nuclides. 60 Co and 137 Cs and β nuclides with relatively low energy 14 C 3 It contains H, etc. Over the past 10 years, the amount of trace contaminated waste resin generated and stored at domestic nuclear power plants is approximately 271,000 liters, and the self-disposal standard limit for classification as general industrial waste ( 137 Cs / 60 Co is 0.1 Bq / g, 14Since the waste is contaminated with radioactivity concentrations slightly exceeding 1.0 Bq / g or less, it has been temporarily stored in the nuclear power plant's waste treatment building rather than being sent to a permanent disposal facility, in order to attenuate or detach the radionuclides attached to the resin for self-disposal. As a result, the nuclear power plant is facing a shortage of available space and disruptions to maintenance operations due to the storage of this contaminated waste in the waste treatment building, and the working environment is in a highly vulnerable state due to factors such as foul odors. Although most of the radionuclides in the contaminated waste generated at nuclear power plants decay and disappear during long-term storage because they have relatively short half-lives, the long-half-life beta radionuclides 14 Since the C nuclide has a half-life of 5,730 years, it is present in trace amounts, but 14 C nuclides remain intact and are adsorbed on the surface of the ion exchange resin 14 If radionuclide C cannot be detached or removed below the self-disposal threshold, it must be sent to a permanent disposal facility at a high disposal cost. The disposal cost for one 200-liter drum is 15.11 million won, and from the perspective of the radioactive waste generator, trace amounts contaminated in the ion exchange resin 14 C or 60 If Co can be detached and removed for self-disposal, disposal costs can be significantly reduced, thereby allowing for the disposal of trace amounts of radionuclides adsorbed on spent waste resin ( 14 C, 60 It has been stored long-term within the power plant until desorption and separation removal technology is developed to remove and self-dispose of substances such as Co., etc., which are adsorbed onto ion exchange resins. 14 C is an inorganic chemical type 14 CO2 or organic chemical form 14 CH4 and H 14 It exists as COOH and is adsorbed onto the resin surface in the form of ions or foreign substances, so it is not easily detached. Ion exchange resins are manufactured from polymeric materials in which ion exchange groups are bonded to polymers with a fine three-dimensional structure, and the adsorbed on the resin surface 14Research on the removal of radioactive materials using microwaves or plasma to detach C for self-disposal has been ongoing for a long time.

[0003] This approach technology is a high-temperature processing technology used when heat-treating polymer resins 14 In addition to C, various environmentally hazardous substances are generated together in gaseous form, and a large amount of secondary waste is generated through the use of adsorbents or filters to remove these substances. Since the disadvantages far outweigh the advantages, it is evaluated as not being a desirable technology in terms of economic feasibility, and thus commercial treatment technology has not yet been developed.

[0005] [Prior Art Literature]

[0006] [Patent Literature]

[0007] 1. Korean Registered Patent No. 10-1279718-0000 (June 21, 2013)

[0008] 2. Korean Registered Patent No. 10-1172247-0000 (2012.08.01.) The problem to be solved

[0009] The present invention is proposed to solve the problems of the aforementioned conventional technology, and its purpose is to provide a radioactive waste resin decontamination treatment device and method that induce self-disposal by desorbing and separating radionuclides from waste resin contaminated with radioactive materials using chemicals and ultrasound in water without emitting toxic gases, minimizes the amount of radioactive exhaust gas generated during desorption, and safely separates and removes desorbed ionic and particulate radioactive materials, thereby reducing the amount of atmospheric pollutants and radioactive material emissions as well as the amount of radioactive waste generated, which can significantly contribute to reducing disposal costs, protecting the natural environment, and carbon neutrality.

[0010] The problems to be solved by the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the description below. means of solving the problem

[0011] The technical problem of the present invention as described above is achieved by the following means.

[0012] (1) A pretreatment unit that aggregates and removes radionuclides by introducing water containing radioactive waste resin and a chemical containing a polymer coagulant;

[0013] A decontamination treatment unit that separates and removes radionuclides adsorbed or attached to the surface by applying acid treatment and ultrasound to pre-treated radioactive waste resin;

[0014] After drying the decontaminated radioactive waste resin to separate the moisture, the organic type generated during the drying stage 14 C is an inorganic type 14 A resin drying treatment unit that converts into CO2; and

[0015] Gaseous phase generated during the resin drying process 14 Adsorbing and removing C nuclides 14 Radioactive waste resin decontamination treatment device including a C nuclide capture unit.

[0016] (2) In the above (1),

[0017] A radioactive waste resin decontamination treatment device characterized by comprising: an ultrasonic decontamination tank equipped with an ultrasonic generator and a resin stirrer; an ion membrane filtration unit for removing radionuclides in the treated water to purify the treated water discharged from the ultrasonic reaction tank; a treated water recovery unit for recirculating the treated water that has passed through the ion membrane filtration unit to the ultrasonic reaction tank; and a resin dewatering tank for dewatering the radioactive waste resin discharged from the ultrasonic reaction tank.

[0018] (3) In the above (2),

[0019] A radioactive waste resin decontamination treatment device characterized by having a bag filter, a carbon electrode membrane, or a multi-stage electrode ion separation membrane connected to remove ionic radionuclides in the purification stage of the above-mentioned treated water.

[0020] (4) In the above (1),

[0021] A radioactive waste resin decontamination treatment device characterized by the above resin drying treatment unit comprising a resin hopper for supplying decontamination resin, a decontamination resin dryer for drying decontamination resin, a moisture separator for separating moist steam accompanied by moisture generated during drying, and a decontamination resin storage tank for storing the dried resin.

[0022] (5) In the above (4),

[0023] Separated while passing through the above moisture separator 3 H is removed in the form of dissolved tritium water (HTO) in water, and organic and inorganic types adsorbed on the resin surface 14 C is a separation tank for separating gaseous radionuclides and organic types among the gaseous radionuclides exiting the separation tank. 14 C is an inorganic type 14 A radioactive waste resin decontamination treatment device characterized by including a catalytic reactor (Pt / Pb) that converts to CO2.

[0024] (6) In the above (1),

[0025] The above C 14 The radionuclide capture unit is in the form of a weapon 14 C that adsorbs and removes CO2 via chemical reaction with LiOH or Ca(OH)2 14 Includes a scrubber, and the above C 14 A radioactive waste resin decontamination treatment device characterized by a scrubber comprising a pellet-type cartridge having an inner cover made of non-woven fabric formed therein.

[0026] (7) In the above (1),

[0027] The decontamination treatment unit is an ion-phase radionuclide (H 14 CO3 - , 14 CO3 -2 )second 14 To convert to CO2 gas, phosphoric acid solution (NH4H2PO4, H3PO4) and acidic solution (H2SO4) are injected to lower the pH to approximately 3–5. 14A radioactive waste resin decontamination treatment device characterized by converting and discharging into CO2 gas.

[0028] (8) In the above (1),

[0029] The ultrasonic generator is vertical and includes a push-pull type transducer, and applies ultrasound to a resin in a slurry state to induce a cavitation effect, thereby [determining] trace amounts attached to the resin 14 A radioactive waste resin decontamination treatment device characterized by removing C.

[0030] (9) In the above (4),

[0031] A radioactive waste resin decontamination treatment device characterized by the decontamination resin dryer being a screw-type continuous heating drying device equipped with a band heater. Effects of the invention

[0032] As described above, the present invention induces self-disposal of waste resin contaminated with radioactive materials by using chemicals and ultrasound to desorb and separate radionuclides underwater without emitting toxic gases, minimizes the amount of radioactive exhaust gas generated during desorption, and safely separates and removes desorbed ionic and particulate radioactive materials, thereby significantly contributing to the reduction of atmospheric pollutants and radioactive material emissions, as well as the reduction of radioactive waste generation, which in turn reduces disposal costs and protects the natural environment and achieves carbon neutrality. Brief explanation of the drawing

[0033] FIG. 1 is a schematic diagram of a radioactive waste resin decontamination treatment device according to the present invention. FIG. 2 is a detailed configuration diagram of a radioactive waste resin decontamination treatment device according to an embodiment of the present invention. FIG. 3 is a detailed configuration diagram of a resin drying treatment unit according to an embodiment of the present invention. FIG. 4 is a detailed flowchart of the radioactive waste resin decontamination treatment process according to an embodiment of the present invention. Specific details for implementing the invention

[0034] Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. The detailed description disclosed below, together with the accompanying drawings, is intended to describe exemplary embodiments of the present invention and is not intended to represent the only embodiment in which the present invention may be practiced. The following detailed description includes specific details to provide a complete understanding of the present invention. However, those skilled in the art will know that the present invention may be practiced without such specific details.

[0035] In some cases, to avoid obscuring the concept of the present invention, known structures and devices may be omitted or illustrated in the form of a block diagram focusing on the core functions of each structure and device.

[0036] Throughout the specification, when a part is described as "comprising" or "including" a component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. Furthermore, the term "...part" as used in the specification refers to a unit that performs at least one function or operation. Additionally, "one (a or an)," "one," "the," and similar related terms may be used in the context describing the invention (particularly in the context of the following claims) to include both singular and plural forms, unless otherwise indicated in the specification or clearly contradicted by the context.

[0037] In describing the embodiments of the present invention, specific descriptions of known functions or configurations will be omitted if it is determined that such detailed descriptions could unnecessarily obscure the essence of the invention. Furthermore, the terms described below are defined considering their functions in the embodiments of the present invention, and these definitions may vary depending on the intentions or practices of the user or operator. Therefore, such definitions should be based on the content throughout this specification.

[0038] Hereinafter, preferred embodiments of the present invention will be described with reference to the attached drawings.

[0039] FIG. 1 is a configuration diagram of a radioactive waste resin decontamination treatment device according to the present invention, wherein the treatment device comprises a pretreatment unit (10), a decontamination treatment unit (20), a resin drying treatment unit (30), and 14 It includes a C nuclide capture unit (40).

[0040] The pretreatment unit (10) removes organic matter and radionuclides by coagulating water containing radioactive waste resin (such as ion exchange resin, hereinafter referred to as resin or waste resin) and a chemical containing a coagulant.

[0041] Preferably, the pretreatment unit (10) according to the embodiment of the present invention comprises a water storage tank (11), a water supply pump (P1), a chemical tank (13), a contaminated water purification pump (P2), a resin storage tank (14), a resin mixer (15), a resin transfer pump (P3), and a purified water supply pump (P4).

[0042] Water stored in the water storage tank (11) is supplied by the water supply pump (P1) to the resin storage tank (14) where waste resin is stored, and at the same time, a predetermined coagulant and neutralizing agent are introduced into the resin storage tank (14) from the chemical tank (13).

[0043] Waste resin is introduced into the ultrasonic decontamination tank (21) by the resin transfer pump (P3), and contaminated water containing coagulated and precipitated substances is returned to the resin storage tank (14) via the contaminated water purification pump (P2) and passing through the multi-stage pretreatment filter (17). The resin storage tank (14) is equipped with a resin mixer (15) to homogenize the resin, and a water level sensor (not shown) is equipped to maintain the ratio of water to waste resin at a constant level.

[0044] The decontamination treatment unit (20) separates and removes radioactive nuclides adsorbed or attached to the surface by applying a chemical treatment (sulfuric acid, hydrochloric acid, nitric acid, bicarbonate, silver nitrate, sodium peroxide, etc.) and ultrasound to the pre-treated radioactive waste resin. At this time, the chemical introduced into the decontamination treatment unit (20) may be introduced directly into the ultrasonic decontamination tank (21), or the chemical may be introduced into the water storage tank (11) and the acid-controlled water may be introduced into the ultrasonic decontamination tank (21).

[0045] To this end, the decontamination treatment unit (20) according to the embodiment of the present invention comprises an ultrasonic decontamination tank (21) equipped with an ultrasonic generator (22) and a resin stirrer (23), an ion separation membrane filtration unit (24) for removing radionuclides in the treated water discharged from the ultrasonic decontamination tank (21), a treated water recovery unit (25) for recirculating the treated water that has passed through the ion separation membrane filtration unit (24) back to the ultrasonic decontamination tank (21), a resin dewatering tank (26) for dewatering the waste resin discharged from the ultrasonic decontamination tank (21), and a chemical supply unit (27).

[0046] Preferably, the ultrasonic generator (22) according to the embodiment of the present invention is vertical and includes a push-pull type vibrator, and applies ultrasound to a resin in a slurry state to cause a cavity effect, thereby removing trace amounts of the resin attached to the resin 14 Detach and remove C.

[0047] Preferably, the ion separation membrane filtration unit (24) according to the embodiment of the present invention comprises at least one filter selected from a bag filter (241), a carbon electrode separation membrane (242), and a multi-stage electrode ion separation membrane (243), and more preferably, the bag filter (241), the carbon electrode separation membrane (242), and the multi-stage electrode ion separation membrane (243) are connected in series.

[0048] Preferably, the decontamination treatment unit (20) according to the embodiment of the present invention comprises ionic radionuclides and 14 To separate and remove C, (1) an alkaline solution is applied to the H adsorbed on the resin. 14 CO3 - , 14 CO3 -2 First, separate it into ionic form, then add additional chemicals. 14 By converting and discharging CO2 gas, or (2) treating with a phosphoric acid solution (NH4H2PO4, H3PO4) 14 It converts into CO2 gas and emits it.

[0049] More specifically, ion-exchanged and adsorbed ionic type (H 14 C03 - / 14 CO3 -- ) and organic type( 14 CH4 / H 14 COOH) 14 C in the gaseous state 14 To convert it into CO2, the pH is lowered to about 3 to 5 using chemicals (sulfuric acid, bicarbonate, etc.), and the organic compound is oxidized and decontaminated by adding silver nitrate and sodium peroxide at about 60 to 80°C.

[0050] In the above embodiment of the present invention, the treated water recovery unit (25) includes a treated water storage tank (251) and a condensate recovery pump (P7), and the waste resin discharged from the ultrasonic decontamination tank (21) is fed into the resin dewatering tank (26) by the waste resin transfer pump (P5) and dewatered.

[0051] The above resin dewatering tank (26) includes a filter inside for dewatering.

[0052] The resin drying treatment unit (30) dries the decontaminated radioactive waste resin to separate it into waste resin and moisture, and then heats it to form an organic type 14 C is an inorganic type 14 Convert to CO2.

[0053] The resin drying treatment unit (30) according to an embodiment of the present invention includes a resin hopper (31) for supplying decontamination resin, a decontamination resin dryer (32) for drying the decontamination resin, a moisture separator (33) for separating moisture-accompanied steam generated during drying, and a decontamination resin storage tank (34) for storing the dried resin.

[0054] The decontamination resin dryer (32) according to the above embodiment of the present invention is a screw-type continuous heating and drying device equipped with a band heater, preferably using a screw-type dryer, adopting a band heater capable of heating the temperature of the outer surface of the dryer to 80 to 90°C, and using a dryer that continuously supplies a certain amount of nitrogen inside to easily release the generated gas.

[0055] In the present invention, the wastewater from the decontamination resin dryer (32) is returned to the resin storage tank (14) by the purification water supply pump (P4).

[0056] Preferably, the moisture separator (33) according to the embodiment of the present invention cools the wet steam separated from the decontamination resin dryer to produce tritium ( 3 A liquid phase consisting of condensate containing H) and an organic type 14 C or / and inorganic type 14 A separation tank (331) for separating gaseous radionuclides composed of CO2, and organic type among the gaseous radionuclides discharged from the separation tank (331). 14 C is an inorganic type 14 It includes a high-temperature catalytic reactor (332) that converts into CO2. The liquid condensate is returned to the ultrasonic decontamination tank (21) by recovery pumps (P6, P7).

[0057] In the present invention 14The C nuclide collection unit (40) is an inorganic type separated from the moisture separator (33). 14 It adsorbs and removes CO2.

[0058] The above C according to the embodiment of the present invention 14 The nuclide collection unit (40) is of the form of an inorganic 14 C that removes CO2 by adsorption using LiOH or Ca(OH)2 through a chemical reaction 14 scrubber 14 It includes a C Scrubber)(41), and the C 14 The scrubber includes a pellet-type cartridge with an inner cover made of non-woven fabric.

[0059] As an embodiment of the present invention, the above 14 The C scrubber (41) is an organic type (332) that is generated while passing through the catalytic reactor (332) during resin drying treatment. 14 C n H m ) Carbon is inorganic carbon ( 14 Radiocarbon converted into CO2 14 It is intended to adsorb and remove C). 14 C scrubber ( 14 While passing through the C Scrubber, more than 95% of radiocarbon ( 14 C) is removed.

[0060] More specifically, radiocarbon ( 14 To remove C), the contained in the released gas 14 CO2 is removed by adsorption by passing it through a scrubber equipped with a high-efficiency activated carbon fiber filter loaded with alkali metal hydroxides [LiOH, Ca(OH)2, etc.].

[0061] High-efficiency adsorbents and radioactive carbon dioxide ( 14 The reaction equation for CO2 is as follows.

[0062] 2 LiOH (s) + 14 CO2(g) → Li2 14 CO3(s) + H2O (g or l)

[0063] Ca(OH)2(s) +14 CO2(g) → Ca 14 CO3(s) + H2O (g or l)

[0064] Lithium hydroxide is carbon dioxide ( 14 Lithium carbonate (Li2), which reacts with CO2, is chemically stable, and does not dissolve in water. 14 As it is converted into CO3, radiocarbon ( 14 Adsorbs C).

[0065] In this invention, for optimal adsorbent application, CO2 concentration As a result of conducting performance tests on different adsorbents under test conditions of 947 ppm and 40% relative humidity, calcium hydroxide was found to have the best adsorption performance, and Ca(OH)2 (soda lime) and LiOH (lithium hydroxide) were also determined to be suitable metal catalysts for use.

[0066] As an embodiment of the present invention, the above 14 The entrance and exit of the exhaust gas inside the C scrubber (41) facility and the interior are made of SUS 316 material to prevent corrosion caused by strong basic adsorbents, and there must be no leakage at the connection points, and a discharge blower is installed at the filter box outlet to discharge the exhaust gas that has passed through the facility.

[0067] 14 A cartridge-type collection filter is installed inside the C scrubber (41) facility, and the cartridge filter is made of a material that is breathable and resistant to moisture, and uses an inner cover made of non-woven fabric so that the impregnated catalyst does not escape from the cartridge and must be completely sealed inside.

[0068] At this time, the pellet-shaped adsorption cartridge inside the collection bag is inorganic radiocarbon ( 14 It adsorbs carbonates (e.g., Li2) by adsorbing CO2. 14 CO3, Ca 14It is removed in the form of CO3, etc. Since the above adsorption cartridge adsorbs long-lasting beta (β) nuclides, it is disposed of by placing it directly in a High Integrity Container (HIC) or by solidifying it with cement and placing it in a drum for permanent disposal.

[0069] In addition, as illustrated in FIG. 4, the present invention comprises the steps of: pre-treating by introducing water containing radioactive waste resin and a chemical containing a coagulant to coagulate and remove radionuclides (1); decontaminating by applying acid treatment and ultrasound to the pre-treated radioactive waste resin to separate and remove radionuclides adsorbed or attached to the surface (2); drying the decontaminated radioactive waste resin to separate the waste resin and moisture (3); and heating the separated moisture to produce a gaseous 14 A method for decontaminating radioactive waste resin is provided, comprising the step (4) of adsorbing and removing C nuclides.

[0070] More specifically, the above step (1) includes a pretreatment process for dissolving and coagulating contaminants attached to the surface of contaminated waste resin, and for this purpose, a coagulant is administered.

[0071] In the above pretreatment process, preferably, organic matter or particulate matter attached to waste resin (e.g., ion exchange resin) is desorbed using microbubbles or ultrasound, and then removed as a coagulated substance (e.g., in the form of carbonate). At this time, the coagulant is not particularly limited, but preferably, a polymeric coagulant (e.g., an acrylamide-based copolymer), sodium bicarbonate, ammonium phosphate, etc., may be used, and the pH is adjusted to about 6 to 7 to improve coagulation efficiency. The coagulated and precipitated sediment is removed in a multi-stage pretreatment filter (17) (e.g., diameter 5 μm).

[0072] Tables 1 to 3 below show foreign substances attached to radioactive waste resin dissolved and separated by chemical agents according to an embodiment of the present invention. 14 The measured decontamination efficiency of C and the contaminated water during sedimentation treatment using a coagulant60 These are experimental results representing the radioactivity removal efficiency of Co radionuclides, along with the flowchart of the first-stage decontamination process (pretreatment step) and simulation values ​​using chemicals and coagulants.

[0073] γ-nuclides using only ultrasound ( 60 Co, 137 Cs) Decontamination result value nuclide Specific radioactivity (Bq / g) note Before processing After processing Removal efficiency (%) 60 Co 0.211 0.015 92.9 Analysis time: 10,000 seconds 0.0068 96.8 0.016 92.4 137 Cs 0.0137 0.011 80.3 0.013 94.9 0.0065 52.6

[0074] using ultrasound and ammonium phosphate 14 C Decontamination result Ammonium phosphate concentration (mol) 14 C(Bq / g) Removal efficiency (%) note 0.01 1.72 45,4 · Raw water: 3.25 Bq / g · Baseline: 0.04 Bq / g 0.1 1.03 67.9 0.5 0.55 82.9 1 0.037 98.9

[0075] Results of radionuclide removal from simulated wastewater using coagulants radionuclide Initial value (Bq / g) Coagulant injection concentration 200ppm 500ppm 1,000ppm 60 Co 2.12E+00 2.11E-02 7.98E-03 7.73E-03 Decontamination Factor (DF) 100.47 265.6 274.2

[0076] According to an embodiment of the present invention, as shown in the results of Tables 1 to 3 above, the decontamination factor value (decontamination factor (DF): 260 to 270) was highest at an amount of coagulant administered of about 500 to 600 ppm.

[0077] The supernatant separated in the above process is introduced into a subsequent ion separation membrane filtration unit (24) and sequentially passes through a bag filter (241), a carbon electrode separation membrane (CDI, 242), and a multi-stage electrode ion separation membrane (FEDI, 243) capable of separating ionic substances while minimizing electricity consumption to remove ionic nuclides contained in the separated supernatant and purify it, and is stored in a treated water storage tank (251) and recirculated as ultrasonic decontamination supply water by a condensate recovery pump (P7) for reuse.

[0078] As shown in Fig. 5, the carbon electrode separator is an ion separation membrane with the lowest electricity consumption and desorption and regeneration functions, and the multi-stage electrode ion separation membrane (FEDI) incorporates a dual voltage control process that efficiently separates silica and hardness by separating the ion value of the influent water with two electrodes.

[0079] In the decontamination process of step (2), the pre-treated waste resin is transferred to an ultrasonic decontamination tank (21) together with the supernatant water, and chemicals and ultrasound are applied to desorb and separate foreign substances and radionuclides.

[0080] At this time, ionic radionuclides (H 14 CO3 - , 14 CO3 -2 ) by additionally adding nitric acid or hydrochloric acid 14 Converted to and emitted as CO2 gas, or using phosphoric acid solutions (NH4H2PO4, H3PO4) 14 It converts into CO2 gas and emits it.

[0081] In addition, during the decontamination process of step (2), ultrasonic waves of 20 to 30 kHz are preferably applied to the resin surface by an ultrasonic oscillator installed in the center, and a push-pull type vibrator may be used for this purpose. Ultrasonic decontamination involves evenly applying ultrasonic waves to the resin surface within a radius of 30 to 80 cm centered on the vertical ultrasonic oscillator, thereby causing ultrasonic waves and cavitation effects to repeatedly occur and subside approximately 25,000 to 30,000 times per second. Through chemical and thermal actions resulting from very small stirring and bubble bursting caused by the vibration, trace amounts of ultrasonic waves attached to the waste resin are removed. 14 C can be easily detached and removed.

[0082] Through the above process, more than 95% of the radionuclides are separated and removed, and the decontaminated waste resin is dehydrated in a resin dehydration tank (26) for a subsequent drying process. At this time, the dehydrated water is returned to the ultrasonic decontamination tank (21) by a condensate recovery pump (P7).

[0083] In the resin drying process of step (3), the waste resin dehydrated in step (2) is transported and dried.

[0084] In step (3) above, the waste resin treated for decontamination in the ultrasonic decontamination tank (21) is transferred to a screw-type continuous heating and drying device (32) equipped with a heat band. Gaseous C released during the drying process 14 edible and inorganic ( 14 CO2, 14 C m H n It comes out in the form of an organic type 14 C is inorganic as it passes through a high-temperature catalyst (Pd / Pt catalyst, 350–450°C) (332). 14 It is converted into CO2.

[0085] In addition, the liquid generated during the drying process 3 H condensate (HTO) is recovered in a separation tank (331).

[0086] In step (4), the inorganic type from step (3) 14 CO2 is C 14 The process of adsorption and removal is performed immediately as it passes through the scrubber (41). At this time, C 14 is preferably Lithium carbonate or calcium carbonate (Li2) on the surface of an adsorbent supported with inorganic hydroxide compounds such as LiOH / Ca(OH)2 14 CO3 / Ca 14 It is adsorbed in the form of CO3.

[0087] At this time, the Li / Ca supported adsorbent is preferably produced by adding water to polyvinyl alcohol (PVA) and polyethylene glycol (PEG) as binder materials, mixing them thoroughly with a mixer, drying at 110–120°C for 3 hours, and then undergoing a calcination process at 200°C for 1 hour and at 350°C for 3 hours to produce a nonwoven fabric with a diameter of 5 mm and a length of 5 mm.

[0088] As shown in FIG. 6, the above Li / Ca-supported adsorbent is in the form of a cartridge packaged in an inner cover made of non-woven fabric to prevent leakage to the outside C 14 Construct a collection filter.

[0089] The foregoing description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention. Accordingly, the embodiments disclosed in the present invention are intended to explain, not limit, the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by such embodiments. The scope of protection of the present invention shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention. Explanation of the symbols

[0090] 10: Preprocessing section 20: Decontamination Treatment Unit 21: Ultrasonic decontamination tank 22: Ultrasonic generator 23: Resin stirrer 24: Ion separation membrane filtration unit 241: Bag filter 242: Carbon electrode separator 243: Multistage electrode ion separator 25: Treated Water Recovery Unit 251: Treated water storage tank P7: Condensate recovery pump 26: Resin dehydration tank 30: Resin drying treatment unit 31: Susie Hopper 32: Decontamination resin dryer 33: Moisture separator 331: Separation group 332: Catalytic reactor 34: Decontamination resin storage tank 40: 14 C nuclide capture unit 41: 14 C scrubber

Claims

Claim 1 A pretreatment unit that coagulates and removes radionuclides by introducing water containing radioactive waste resin and chemicals containing a coagulant; a decontamination unit that separates and removes radionuclides adsorbed or attached to the surface of the pretreated radioactive waste resin by applying acid treatment and ultrasound; and the decontaminated radioactive waste resin is dried to separate moisture and the organic type desorbed during the heating process 14 C is inorganic 14 A resin drying treatment unit that converts into CO2; and a gaseous phase generated during resin drying 14 Adsorbs and removes C nuclides 14 The decontamination treatment unit includes a C radionuclide capture unit, wherein the decontamination treatment unit comprises an ultrasonic decontamination tank equipped with an ultrasonic generator and a resin stirrer, an ion membrane filtration unit for removing ionic radionuclides in the treated water to purify the treated water discharged from the ultrasonic decontamination tank, and a treated water recovery unit for recirculating the treated water from which ionic substances have been removed to the ultrasonic decontamination tank; and includes a resin dehydration tank for dehydrating radioactive waste resin discharged from the ultrasonic decontamination tank, wherein the purification of the treated water is performed by connecting a bag filter, a carbon electrode separator, and a multi-stage electrode ion separator in series, and the resin drying treatment unit includes a resin hopper for supplying decontamination resin, a decontamination resin dryer for drying decontamination resin, a moisture separator for separating wet steam accompanied by moisture generated during drying, and a decontamination resin storage tank for storing the dried resin, wherein the moisture separator cools the wet steam separated from the decontamination resin dryer to form a liquid phase consisting of condensate containing tritium (HTO) and an organic type 14 C or / and inorganic type 14 A separation tank for separating gaseous radionuclides composed of CO2; and organic type among the gaseous radionuclides discharged from the separation tank 14 C is an inorganic type 14 It includes a catalytic reactor that converts into CO2, and the above 14 The C nuclide capture unit is in the form of an inorganic 14 C that adsorbs and removes CO2 through a chemical reaction with LiOH or Ca(OH) 14 Includes a scrubber, and the above C 14 The scrubber includes a pellet-type cartridge with an inner cover made of non-woven fabric, and the decontamination treatment unit is for ionic radionuclides and 14 To separate and remove C, additional acid is added. 14 By converting and emitting it as CO2 gas, or by adding a phosphoric acid solution 14 It converts and emits CO2 gas, and the ultrasonic generator is vertical and includes a push-pull type vibrator; it applies ultrasound to the resin in a slurry state to induce a cavitation effect, thereby [determining] trace amounts attached to the resin 14 A radioactive waste resin decontamination treatment device characterized by detaching and removing C. Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 delete Claim 8 delete Claim 9 A radioactive waste resin decontamination treatment device characterized in that, in claim 1, the decontamination resin dryer is a screw-type continuous heating and drying device equipped with a band heater.

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