A regeneration decontamination method for radioactive waste resin

Abstract

The present invention provides a radioactive waste resin regenerative decontamination treatment device, comprising a radioactive waste resin transmission device, an H2SO4 elution chamber connected to the radioactive waste resin transmission device through a pipeline, a resin elution residual liquid separation chamber connected to the H2SO4 elution chamber through a pipeline, an H2SO4 residual liquid neutralization chamber connected to the resin elution residual liquid separation chamber through a pipeline, a waste liquid evaporation device connected to the H2SO4 residual liquid neutralization chamber through a pipeline, a cement solidification device connected to the waste liquid evaporation device through a pipeline, and a control room connected to the resin elution residual liquid separation chamber through a pipeline, wherein a radiation monitoring instrument and a three-way valve are sequentially arranged on the pipeline connecting the resin elution residual liquid separation chamber and the control room, and the three-way valve is connected to the H2SO4 elution chamber through a pipeline. The present invention provides a radioactive waste resin regenerative decontamination treatment method. The radioactive waste resin regenerative decontamination treatment device and treatment method provided by the present invention have simple structure, convenient operation, safety and reliability, and good treatment effect.

Description

Technical Field

[0001] The present invention relates to the technical field of radioactive waste resin regeneration treatment, and in particular to a radioactive waste resin regeneration decontamination treatment device and a treatment method thereof. Background Art

[0002] Ion exchange resins are commonly used to purify the primary coolant in the primary process system of pressurized water reactor nuclear power units (such as chemical volume system, boron recovery, radioactive waste liquid evaporation system and spent fuel cooling water pool). The ion exchange resins used in the primary process system need to be disposed of as solid waste after one overhaul cycle (12 to 18 months) in service. For a pressurized water reactor nuclear power plant with an installed capacity of ×1000MWe, the actual amount of radioactive waste resin generated each year is about 6 to 8m 3 .

[0003] At present, the main method for domestic disposal of radioactive waste resin is cement solidification. After treatment by this method, the volume of cement solidified body is 2 to 3 times the volume of waste resin, and the cement solidified body obtained each year reaches about 1 / 3 of the annual output of solid waste from nuclear power plants. The treatment of radioactive solid waste from nuclear power plants follows the principle of minimization to reduce the cost of later disposal. Therefore, technologies such as super compression with relatively small volume increase ratio and high integral container dry storage have gradually been applied in nuclear power plants. However, the volume increase ratio of these two treatment methods is greater than 1, and no real volume reduction has been achieved.

[0004] At present, there are attempts to use wet oxidation to degrade radioactive waste resin, and there are also attempts to use supercritical water oxidation to treat radioactive waste resin. However, both treatment methods have problems such as complex processes and high requirements for equipment.

[0005] Therefore, there is a need to adopt a method with simple structure, convenient operation, safety and reliability, and good treatment effect to treat radioactive waste resin. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a radioactive waste resin regeneration decontamination treatment device and a treatment method thereof which has a simple structure, is convenient to operate, is safe and reliable, and has a good treatment effect.

[0007] In order to solve the above technical problems, the present invention provides a regenerative decontamination treatment device for radioactive waste resin, comprising a radioactive waste resin transmission device, an H2SO4 elution chamber connected to the radioactive waste resin transmission device through a pipeline, a resin elution residual liquid separation chamber connected to the H2SO4 elution chamber through a pipeline, an H2SO4 residual liquid neutralization chamber connected to the resin elution residual liquid separation chamber through a pipeline, a waste liquid evaporation device connected to the H2SO4 residual liquid neutralization chamber through a pipeline, a cement solidification device connected to the waste liquid evaporation device through a pipeline, and a control room connected to the resin elution residual liquid separation chamber through a pipeline, wherein a radiation monitoring instrument and a three-way valve are sequentially arranged on the pipeline connecting the resin elution residual liquid separation chamber and the control room, and the three-way valve is connected to the H2SO4 elution chamber through a pipeline.

[0008] Furthermore, a resin injector is provided on the connecting pipe between the radioactive waste resin transfer device and the H2SO4 elution chamber.

[0009] Furthermore, delivery pumps are provided in the pipelines between the H2SO4 elution chamber and the resin elution residual liquid separation chamber, between the resin elution residual liquid separation chamber and the H2SO4 residual liquid neutralization chamber, between the H2SO4 residual liquid neutralization chamber and the waste liquid evaporation device, between the waste liquid evaporation device and the cement solidification device, and between the resin elution residual liquid separation chamber and the release control chamber.

[0010] The present invention also provides a regenerative decontamination method for radioactive waste resin, comprising the following steps:

[0011] The radioactive waste resin in the radioactive waste resin transfer device is transported to the H2SO4 elution chamber;

[0012] The radioactive waste resin is eluted with H2SO4 solution in the H2SO4 elution chamber;

[0013] After elution, the waste resin and elution residue are transported to the resin elution residue separation chamber for solid-liquid separation;

[0014] The separated waste resin is monitored by a radiation monitoring instrument. If the radioactivity meets the clearance requirements, it is transported to the clearance room through a three-way valve. If the radioactivity does not meet the clearance requirements, it is returned to the H2SO4 elution room through a three-way valve for further elution.

[0015] The separated elution residue is transported to the H2SO4 residue neutralization chamber for neutralization treatment;

[0016] The neutralized elution residual liquid is transported to the waste liquid evaporation device for evaporation and concentration, the evaporated condensate is sent to the nuclear island liquid effluent discharge system, and the concentrated liquid is transported to the cement solidification device for solidification treatment.

[0017] Furthermore, the inner wall of the H2SO4 elution chamber is lined with rubber for corrosion protection, and a mechanical agitator is arranged inside the H2SO4 elution chamber.

[0018] Furthermore, the concentration of the H2SO4 solution in the H2SO4 elution chamber is 3.5-4.5 mol / L.

[0019] Furthermore, the alkaline solution used for the neutralization treatment in the H2SO4 residual liquid neutralization chamber is a NaOH solution.

[0020] Furthermore, the pH of the eluted residual liquid in the H2SO4 residual liquid neutralization chamber after being neutralized by the NaOH solution is controlled at 6-9.

[0021] Furthermore, the waste liquid evaporation device is a nuclear power plant radioactive waste liquid evaporation device.

[0022] Furthermore, the cement solidification device is a cement solidification device for radioactive waste concentrate from a nuclear power plant.

[0023] The present invention provides a regenerative decontamination treatment device for radioactive waste resin and a treatment method thereof, wherein an H2SO4 elution chamber is provided, and radioactive waste resin is eluted chemically to make it into ordinary waste resin, thereby avoiding the problem of nuclide leaching after subsequent cement solidification of radioactive waste resin. A resin elution residual liquid separation chamber, an H2SO4 residual liquid neutralization chamber and a waste liquid evaporation device are provided, and the neutralized elution residual liquid is evaporated by the waste liquid evaporation device, and the generated radioactive concentrated liquid is then cement solidified, which can reduce the treatment amount of radioactive waste liquid and generally play a role in reducing the volume of radioactive waste resin. At the same time, the present invention provides a regenerative decontamination treatment device for radioactive waste resin and a treatment method thereof, and the equipment used are all mature equipment, which is economical, safe, and highly reliable, and can continuously treat radioactive waste resin, thereby improving the treatment efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic structural diagram of a radioactive waste resin regeneration decontamination treatment device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The ions in the solid impurities adsorbed by the nuclear island cationic resin exist in the form of free ions, except for a few metal ions contained in solid particles. Therefore, the present invention provides a radioactive waste resin regeneration decontamination treatment device and a treatment method thereof, which adopts a regeneration process similar to conventional resins by adding sulfuric acid for elution, so that the adsorbed radioactive metal ions are released from the resin and restored to a free state and enter the elution residue, so that the radioactive waste resin can be decontrolled, and then the elution residue containing radioactive ions is subsequently treated by the nuclear island waste liquid evaporation process. The specific treatment device and treatment method are as follows.

[0026] See also Figure 1A radioactive waste resin regenerative decontamination treatment device provided by an embodiment of the present invention comprises a radioactive waste resin transmission device 1, an H2SO4 elution chamber 2 connected to the radioactive waste resin transmission device 1 through a pipeline, a resin elution residual liquid separation chamber 3 connected to the H2SO4 elution chamber 2 through a pipeline, an H2SO4 residual liquid neutralization chamber 4 connected to the resin elution residual liquid separation chamber 3 through a pipeline, a waste liquid evaporation device 5 connected to the H2SO4 residual liquid neutralization chamber 4 through a pipeline, a cement solidification device 7 connected to the waste liquid evaporation device 5 through a pipeline, and a control chamber 6 connected to the resin elution residual liquid separation chamber 3 through a pipeline. A radiation monitoring instrument 8 and a three-way valve 9 are sequentially arranged on the pipeline connecting the resin elution residual liquid separation chamber 3 and the control chamber 6, and the three-way valve 9 is connected to the H2SO4 elution chamber 2 through a pipeline.

[0027] Wherein, a resin injector 10 is arranged on the connecting pipe between the radioactive waste resin transfer device 1 and the H2SO4 elution chamber 2.

[0028] Among them, a delivery pump K2 is arranged on the pipeline between the H2SO4 elution chamber 2 and the resin elution residual liquid separation chamber 3, a delivery pump K6 is arranged on the pipeline between the resin elution residual liquid separation chamber 3 and the H2SO4 residual liquid neutralization chamber 4, a delivery pump K7 is arranged on the pipeline between the H2SO4 residual liquid neutralization chamber 4 and the waste liquid evaporation device 5, a delivery pump K8 is arranged on the pipeline between the waste liquid evaporation device 5 and the cement solidification device 7, and a delivery pump K3 is arranged on the pipeline between the resin elution residual liquid separation chamber 3 and the release control chamber 6.

[0029] The present invention also provides a regenerative decontamination method for radioactive waste resin, comprising the following steps:

[0030] Step 1) The radioactive waste resin in the radioactive waste resin transfer device 1 is transported to the H2SO4 elution chamber 2.

[0031] Step 2) The radioactive waste resin is eluted with H2SO4 solution in H2SO4 elution chamber 2.

[0032] Step 3) After elution, the waste resin and the elution residue are transported to the resin elution residue separation chamber 3 for solid-liquid separation.

[0033] Step 4) The separated waste resin is monitored by a radiation monitoring instrument 8. If the radioactivity meets the control requirements, it is transported to the control chamber 6 through a three-way valve 9. If the radioactivity does not meet the control requirements, it is returned to the H2SO4 elution chamber 2 through a three-way valve 9 for further elution.

[0034] Step 5) The separated elution residue is transported to the H2SO4 residue neutralization chamber 4 for neutralization treatment.

[0035] Step 6) The neutralized elution residue is transported to the waste liquid evaporation device 5 for evaporation and concentration, the evaporated condensate is sent to the nuclear island liquid effluent discharge system, and the concentrated liquid is transported to the cement solidification device 7 for solidification treatment.

[0036] The inner wall of the H2SO4 elution chamber 2 is lined with rubber for corrosion protection, and a mechanical stirrer is arranged inside the H2SO4 elution chamber 2.

[0037] Among them, the concentration of H2SO4 solution in H2SO4 elution chamber 2 is 3.5-4.5 mol / L.

[0038] The alkaline solution used for the neutralization treatment in the H2SO4 residual liquid neutralization chamber 4 is a NaOH solution.

[0039] Among them, the pH of the eluted residual liquid in the H2SO4 residual liquid neutralization chamber 4 after being neutralized by the NaOH solution is controlled at 6-9.

[0040] In order to avoid duplicate construction of equipment, the waste liquid evaporation device 5 is a nuclear power plant radioactive waste liquid evaporation device.

[0041] In order to avoid duplicate construction of equipment, the cement solidification device 7 is a cement solidification device for radioactive waste liquid concentrate from a nuclear power plant.

[0042] The following is a detailed description of a radioactive waste resin regeneration decontamination treatment device and a treatment method thereof provided by the present invention in conjunction with specific examples.

[0043] The radioactive waste resin collected by the nuclear power plant is transferred from the radioactive waste resin transfer device 1 to the H2SO4 elution chamber 2 with a stirrer via the resin injector 10. In the H2SO4 elution chamber 2, the radioactive waste resin is soaked, stirred and eluted with a H2SO4 solution with a volume fraction of 4 mol / L. The soaking, stirring and elution is performed for 2 hours to remove the radioactive metal nuclides adsorbed on the radioactive waste resin. After the elution is completed, the waste resin and the H2SO4 residual liquid are sent to the resin elution residual liquid separation chamber 3 by the delivery pump K2 for separation. The elution residual liquid is sent to the H2SO4 residual liquid neutralization chamber 4 for neutralization treatment via the delivery pump K6. The H2SO4 residual liquid neutralization chamber 4 uses NaOH solution to neutralize the sulfuric acid in the elution residual liquid. The pH of the solution after the neutralization reaction is controlled at 6 to 9. The waste liquid after the neutralization reaction is completed is sent to the waste liquid evaporation device 5 by the delivery pump K7, and the condensed liquid obtained by evaporation is discharged into the nuclear island liquid effluent discharge system. The concentrated liquid obtained by evaporation is discharged by the delivery pump K8 to the cement solidification device 7 for solidification.

[0044] After the eluted waste resin is pumped out by the delivery pump K3, the radioactivity level of the waste resin is monitored when it flows through the radiation monitoring instrument 8 on the pipeline. If the radioactivity of the waste resin reaches the clearance level, the waste resin is delivered to the clearance room 6 through the three-way valve 9. If the radioactivity of the waste resin does not reach the clearance level, the waste resin is returned to the H2SO4 elution room 2 through the three-way valve 9 for further elution.

[0045] The present invention provides a radioactive waste resin regeneration decontamination treatment device and a treatment method thereof, which can reduce the radioactive contamination level in the process of treating radioactive waste resin as much as possible, and ensure the health and personal safety of the staff. The present invention is analogous to the regeneration technology of traditional resins, and uses the waste resin regeneration decontamination method to repeatedly elute the radioactive waste resin through a sulfuric acid solution until the radioactivity level of the radioactive waste resin reaches the control level, so that the radioactivity becomes ordinary waste resin, so as to facilitate subsequent further treatment. The radioactive waste resin regeneration decontamination treatment device and a treatment method thereof of the present invention can not only effectively remove the radioactive nuclides in the radioactive waste resin and reduce the treatment amount of the radioactive waste liquid, but also can generally reduce the volume of the radioactive waste resin during cement solidification treatment. Moreover, the method is reliable, safe, and easy to operate, and can facilitate the recycling treatment of radioactive waste resins in nuclear power plants, with high treatment efficiency, low cost, good economic benefits, and high promotion value and good application prospects.

[0046] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for regenerating and decontaminating radioactive waste resin, characterized in that: The radioactive waste resin regeneration decontamination treatment device used in the treatment method comprises a radioactive waste resin transmission device (1), an H2SO4 elution chamber (2) connected to the radioactive waste resin transmission device (1) through a pipeline, a resin elution residual liquid separation chamber (3) connected to the H2SO4 elution chamber (2) through a pipeline, an H2SO4 residual liquid neutralization chamber (4) connected to the resin elution residual liquid separation chamber (3) through a pipeline, a waste liquid evaporation device (5) connected to the H2SO4 residual liquid neutralization chamber (4) through a pipeline, a cement solidification device (7) connected to the waste liquid evaporation device (5) through a pipeline, and a control room (6) connected to the resin elution residual liquid separation chamber (3) through a pipeline, and a radiation monitoring instrument (8) and a three-way valve (9) are sequentially arranged on the pipeline connecting the resin elution residual liquid separation chamber (3) and the control room (6), and the three-way valve (9) is connected to the H2SO4 elution chamber (2) through a pipeline; The processing method comprises the following steps: The radioactive waste resin in the radioactive waste resin transfer device (1) is transferred to the H2SO4 elution chamber (2); The radioactive waste resin is eluted with H2SO4 solution in the H2SO4 elution chamber (2); After elution, the waste resin and elution residue are transported to the resin elution residue separation chamber (3) for solid-liquid separation; The separated waste resin is monitored by a radiation monitoring instrument (8). If the radioactivity reaches the control clearance requirement, it is transported to the control clearance room (6) through a three-way valve (9). If the radioactivity does not reach the control clearance requirement, it is returned to the H2SO4 elution room (2) through a three-way valve (9) for further elution. The separated elution residue is transported to the H2SO4 residue neutralization chamber (4) for neutralization treatment; The neutralized elution residue is transported to the waste liquid evaporation device (5) for evaporation and concentration, the evaporated condensate is sent to the nuclear island liquid effluent discharge system, and the concentrated liquid is transported to the cement solidification device (7) for solidification treatment.

2. The method for regenerative decontamination of radioactive waste resin according to claim 1, characterized in that: A resin injector (10) is provided on the connecting pipe between the radioactive waste resin transfer device (1) and the H2SO4 elution chamber (2).

3. The method for regeneration and decontamination of radioactive waste resin according to claim 1, characterized in that: The pipelines between the H2SO4 elution chamber (2) and the resin elution residual liquid separation chamber (3), between the resin elution residual liquid separation chamber (3) and the H2SO4 residual liquid neutralization chamber (4), between the H2SO4 residual liquid neutralization chamber (4) and the waste liquid evaporation device (5), between the waste liquid evaporation device (5) and the cement solidification device (7), and between the resin elution residual liquid separation chamber (3) and the release control chamber (6) are all provided with delivery pumps.

4. The method for regeneration and decontamination of radioactive waste resin according to claim 1, characterized in that: The inner wall of the H2SO4 elution chamber (2) is lined with rubber for corrosion protection, and a mechanical stirrer is arranged inside the H2SO4 elution chamber (2).

5. The method for regeneration and decontamination of radioactive waste resin according to claim 1, characterized in that: The concentration of the H2SO4 solution in the H2SO4 elution chamber (2) is 3.5-4.5 mol / L.

6. The method for regenerative decontamination of radioactive waste resin according to claim 1, characterized in that: The alkaline solution used for the neutralization treatment in the H2SO4 residual liquid neutralization chamber (4) is a NaOH solution.

7. The method for regenerative decontamination of radioactive waste resin according to claim 6, characterized in that: The pH of the eluted residual liquid in the H2SO4 residual liquid neutralization chamber (4) after being neutralized by the NaOH solution is controlled at 6-9.

8. The method for regeneration and decontamination of radioactive waste resin according to claim 1, characterized in that: The waste liquid evaporation device (5) is a radioactive waste liquid evaporation device of a nuclear power plant.

9. The method for regeneration and decontamination of radioactive waste resin according to claim 1, characterized in that: The cement solidification device (7) is a cement solidification device for radioactive waste liquid concentrate from a nuclear power plant.

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