A method and system for treating radioactive waste liquid generated by an accelerator for producing medical isotopes

Abstract

The present invention discloses a method and a system for treating radioactive waste liquid generated in the production of medical isotopes by an accelerator. The method of the present invention includes the following steps: S100, classifying and collecting the accelerator activation water, the isotope production target and beam collector activation water, the low-level radioactive waste liquid generated by the separation hot cell, and the medium-level radioactive waste liquid generated by the separation process in the radioactive waste liquid generated in the production of medical isotopes by the accelerator; S200, treating the accelerator activation water, the isotope production target and beam collector activation water, the low-level radioactive waste liquid generated by the separation hot cell, and the medium-level radioactive waste liquid generated by the separation process respectively, and simultaneously conducting combined treatment on the medium-level radioactive waste liquid and the low-level radioactive waste liquid. The present invention classifies and collects from the source according to the radioactive waste liquid generated in the process of producing medical isotopes by bombarding an isotope production target with an accelerator. The classified collection of radioactive waste liquid is more conducive to waste minimization and cost reduction in treatment.

Description

Technical Field

[0001] The present invention belongs to the field of radioactive contamination material treatment, and particularly relates to a method and a system for treating radioactive waste liquid generated during the production of medical isotopes by bombarding isotopes with an accelerator to produce a target. Background Art

[0002] Medical isotopes are the material basis for nuclear medicine diagnosis and treatment. Using medical isotopes for the diagnosis and treatment of major diseases such as cardiovascular and cerebrovascular diseases, malignant tumors, and neurodegenerative diseases has irreplaceable advantages. Based on an accelerator to generate a high-power proton beam and couple it with an isotope production target, high-yield and high-efficiency production of medical radioactive isotopes is achieved. Through efficient separation and purification, high-yield, high-purity, and high-efficiency production and separation of medical isotopes are realized, thus providing good support and guarantee for the preparation of isotope-targeted therapeutic drugs.

[0003] Ordinary nuclear medicine and nuclear technology utilization projects mainly discharge the waste liquid after temporary storage and decay. For example, the waste liquid containing I-131 generally meets the discharge standard after being temporarily stored for no more than 180 days. Invention patent CN 115223741 A discloses a treatment method for short-lived radionuclides used in nuclear medicine in nuclear technology utilization. The general characteristic of this radioactive waste liquid is that it can reach the clearance level for external discharge after decaying for a short time (less than 1 year) and reach the final disposal state. This method is not applicable to radioactive nuclides with a longer half-life, such as radioactive nuclides with a half-life greater than 1 year.

[0004] The radioactive waste liquid generated by nuclear power plants is generally in the order of magnitude of 10 5 ~10 7 Bq / L. Generally, processes such as flocculation, filtration, ion exchange, or filtration evaporation are adopted. This process mainly targets radioactive waste liquid with relatively few radionuclide species, low activity, and large annual production, and has high construction costs and high energy consumption during operation, etc. The radioactive waste liquid treatment system disclosed in invention patent CN111768885B mainly targets the radioactive waste liquid generated by nuclear power plants, and its main characteristics are low radioactivity (its specific activity is generally in the range of 10 5 ~10 7 Bq / L), few types of radioactive nuclides contained ( 137 Cs, 89 Sr, 90 Sr, 58 Co, 110m Ag, 3 H, etc.), and a large liquid production (tens of m 3 / a), through a large amount of filtration and ion exchange, concentrated liquid and a large amount of secondary radioactive waste are produced. The liquid treatment finally meets the requirements of the coastal discharge limit for discharge. A final solidification system is also required to treat the concentrated liquid and secondary solid waste. This method is not applicable to the waste liquid produced by isotope separation with a relatively small annual production volume of waste liquid (0.5 - 1 m 3 ), a relatively high specific activity of radioactivity (10 10 - 10 12 Bq / L), and a relatively large number of radionuclides (about more than 300 with half-lives ranging from 1 hour to several decades), as well as the activated waste water generated from the cooling water of accelerators, isotope production targets, etc. Firstly, the investment cost is too high. Secondly, filtration and ion exchange are not applicable to this kind of medium- and high-level radioactive waste liquid with complex nuclides, and it cannot be completely purified to the discharge standard through filtration and ion exchange.

[0005] The radioactive waste liquid generated during the production of medical isotopes is different from the waste liquid generated by traditional nuclear medicine, nuclear technology applications, and nuclear power plants. Taking the production of α-medical isotopes ([[]] 225 Ac and 223 Ra) by bombarding thorium targets with protons as an example, the source term in the medium radioactive waste liquid generated during the separation process has particularity. The activity of the waste liquid after separation is about 10 10 - 10 12 Bq / L, and the number of radionuclide species contained is as many as more than 300. The annual production volume is not large (generally not more than 1 m 3 / year), the half-life distribution range of the nuclides is wide, from a few minutes to thousands of years. Among them, the proportion of nuclides with a half-life less than 1 hour is 37.70%, the proportion of nuclides with a half-life greater than or equal to 1 hour and less than 1 day is about 14.98%, the proportion of nuclides with a half-life greater than or equal to 1 day and less than 30 days is about 36.44%, the proportion of nuclides with a half-life greater than or equal to 30 days and less than 1 year is 10.21%, and the proportion of nuclides with a half-life greater than 1 year is about 0.67%.

[0006] In summary, due to the particularity of the radioactive waste liquid produced by accelerator production of medical isotopes, its specific activity after 5 years of cooling is about 10 9 - 10 10 Bq / L. These waste liquids cannot be temporarily stored for decay and then discharged like ordinary nuclear medicine and nuclear technology utilization projects; the radioactive waste liquid generated by nuclear power plants is generally in the order of 10 5 - 10 7 Bq / L. Generally, processes such as flocculation, filtration, ion exchange, or filtration evaporation are adopted. This process is mainly aimed at radioactive waste liquids with relatively few nuclide species, low activity, and relatively large annual production volume, and has high construction costs and high energy consumption during operation, etc., and is also not applicable to the waste liquid of the present invention. Therefore, there is an urgent need for a treatment method for the radioactive waste liquid produced by accelerator production of medical isotopes. Summary of the Invention

[0007] In view of this, the object of the present invention is to provide a method and a system for treating radioactive waste liquid generated by an accelerator in the production of medical isotopes. The present invention realizes the minimum management of waste through source control, reasonable classification and selection of reasonable waste liquid treatment processes. After taking necessary pretreatment steps (classification, collection, etc.), treatment steps (purification, solidification, etc.), storage, conditioning, etc., it meets the requirements of safe discharge of waste or off-site safe transportation, and achieves the final treatment requirements of the site at a relatively low construction cost, ensuring the sustainable progress of isotope production.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] In the first aspect, the present invention provides a method for treating radioactive waste liquid generated by an accelerator in the production of medical isotopes, including the following steps:

[0010] S100. Classify and collect the accelerator activation water, isotope production target and beam collector activation water, low-level radioactive waste liquid generated by the separation hot cell, and medium-level radioactive waste liquid generated by the separation process in the radioactive waste liquid generated by the accelerator bombarding the isotope production target to produce medical isotopes;

[0011] S200. Treat the accelerator activation water, the isotope production target and beam collector activation water, the low-level radioactive waste liquid generated by the separation hot cell, and the medium-level radioactive waste liquid generated by the separation process respectively as follows:

[0012] Cool the accelerator activation water and sample and monitor the activity. If it meets the clearance discharge standard, it will be discharged after clearance;

[0013] Cool the isotope production target and beam collector activation water and sample and monitor the activity. If it meets the clearance discharge standard, it will be discharged after clearance. If it does not meet the clearance discharge standard, the following treatment will be carried out: filter the waste liquid and then perform ion exchange to obtain a purified liquid; sample and monitor the activity of the purified liquid. If it meets the clearance discharge standard, it will be discharged after clearance or used as a solidification additive liquid;

[0014] Sample and monitor the pH value of the low-level radioactive waste liquid generated by the separation hot cell, adjust the waste liquid to alkaline by adding chemical reagents, and use the adjusted waste liquid as an additive liquid for solidifying the medium-level radioactive waste liquid;

[0015] Capture the liquid particles in the gas generated by the medium-level radioactive waste liquid generated by the separation process, filter the captured gas to remove aerosols and water vapor, and input the filtered gas into the exhaust system for controlled discharge; sample and monitor the pH value of the medium-level radioactive waste liquid, adjust the waste liquid to alkaline by adding chemical reagents, and perform solidification treatment on the adjusted waste liquid.

[0016] In the above method for treating radioactive waste liquid generated in the production of medical isotopes by an accelerator, the medical isotope is 225 Ac, 223 Ra, 211 At, 68 Ge, and 67 at least one of Cu. As an example, the radioactive waste liquid generated in the production of medical isotopes by the accelerator is the radioactive waste liquid generated by bombarding a thorium target with protons to produce α-medical isotopes 225 Ac and 223 Ra.

[0017] In the above method for treating radioactive waste liquid generated in the production of medical isotopes by an accelerator, in the treatment of the accelerator-activated water, the cooling and activation degree monitoring time of the accelerator-activated water is no more than 1 year;

[0018] In the treatment of the activated water of the isotope production target and beam collector, the cooling and activity monitoring time of the activated water of the isotope production target and beam collector is 1 year;

[0019] The release control discharge standards are as follows: the specific activity of α does not exceed 1 Bq / L, and the specific activity of β does not exceed 10 Bq / L.

[0020] In the above method for treating radioactive waste liquid generated in the production of medical isotopes by an accelerator, in the treatment of the activated water of the isotope production target and beam collector, the wet solid waste generated by the filtration and the ion exchange is collected and temporarily stored, and is transported out for treatment after release control, and the wet solid waste that cannot be released is solidified;

[0021] In the treatment of the activated water of the isotope production target and beam collector, the filtration is used to remove oils, colloids, and particulate matters in the waste liquid;

[0022] The ion exchange is used to remove free nuclides in the waste liquid.

[0023] In the above method for treating radioactive waste liquid generated in the production of medical isotopes by an accelerator, in the treatment of the low-level radioactive waste liquid generated by the separation hot cell, before sampling and monitoring the pH value of the low-level radioactive waste liquid generated by the separation hot cell, it is filtered to remove particulate impurities, and the wet solid waste generated by the filtration is solidified;

[0024] In the treatment of the low-level radioactive waste liquid generated by the separation hot cell, the activity is monitored while monitoring the pH value of the low-level radioactive waste liquid generated by the separation hot cell, for estimating the total radioactivity after solidification;

[0025] The solidification treatment is cement solidification, and the pH value of the alkaline in the treatment of the low-level radioactive waste liquid generated by the separation hot cell is 8-13;

[0026] In the treatment of the low-level radioactive waste generated by the separation hot cell, the sample taken for monitoring the pH value of the low-level radioactive waste is refluxed into the low-level radioactive waste generated by the separation hot cell;

[0027] In the treatment of the medium-level radioactive waste generated by the separation process, it further includes filtering the medium-level radioactive waste to remove particulate impurities, and solidifying the wet solid waste generated by the filtering;

[0028] In the treatment of the medium-level radioactive waste generated by the separation process, while monitoring the pH value of the medium-level radioactive waste generated by the separation hot cell, the activity is monitored to estimate the total radioactivity after solidification;

[0029] The solidification treatment is cement solidification, and the pH value of the medium-level radioactive waste generated by the separation process is 8 - 13;

[0030] In the treatment of the medium-level radioactive waste generated by the separation process, the sample taken for monitoring the pH value of the medium-level radioactive waste, and the waste liquid generated in the capture step and the filtering step are refluxed together into the storage tank for the medium-level radioactive waste generated by the separation process;

[0031] The low-level radioactive waste generated by the separation hot cell and the medium-level radioactive waste generated by the separation process are jointly subjected to the solidification treatment.

[0032] In the second aspect, the present invention provides a treatment system for radioactive waste generated by an accelerator for producing medical isotopes, which is the system used for the above method, including:

[0033] An accelerator activation water unit, including a first activation wastewater collection tank and a first activity sampling and monitoring device, and the first activity sampling and monitoring device is installed on the first activation wastewater collection tank;

[0034] An isotope production target and beam collector activation water treatment unit, including a second activation wastewater collection tank, a second activity sampling and monitoring device, a third activity sampling and monitoring device, a first filter, an ion exchange bed, and a purified water collection tank. The second activation wastewater collection tank, the first filter, the ion exchange bed, and the purified water collection tank are connected in sequence. The second activation degree sampling and monitoring device is installed on the second activation wastewater collection tank, and the third activity sampling and detection device is installed on the purified water collection tank;

[0035] A low-level radioactive waste treatment unit generated by a separation hot cell, including a first pre-filter, a low-level radioactive waste temporary storage tank, a low-level radioactive waste sampling box, and a first chemical reagent adding device. The first pre-filter is installed on the input pipeline of the low-level radioactive waste temporary storage tank. The low-level radioactive waste sampling box is connected to the sampling port of the low-level radioactive waste temporary storage tank, and the first chemical reagent adding device is connected to the reagent adding port of the low-level radioactive waste temporary storage tank;

[0036] The intermediate-level radioactive waste treatment unit generated by the separation process includes a second pre-filter, an intermediate-level radioactive waste storage tank, a trap, a second filter, an intermediate-level radioactive waste sampling box, and a second chemical reagent addition device. The second pre-filter is installed on the input pipeline of the intermediate-level radioactive waste storage tank. The exhaust outlet of the intermediate-level radioactive waste storage tank is connected to the trap, the trap is connected to the second filter, the sampling outlet of the intermediate-level radioactive waste storage tank is connected to the intermediate-level radioactive waste sampling box, and the second chemical reagent addition device is connected to the reagent addition port of the intermediate-level radioactive waste storage tank;

[0037] The solidification treatment system, the waste liquid outlet of the purified water collection pool is connected to the solidification treatment system and a flowmeter is provided on the connecting pipeline. The waste liquid outlet of the low-level radioactive waste storage tank is connected to the solidification treatment system and a low-level radioactive waste metering tank is provided on the connecting pipeline. The waste liquid outlet of the intermediate-level radioactive waste storage tank is connected to the solidification treatment system and an intermediate-level radioactive waste metering tank is provided on the connecting pipeline.

[0038] In the above-mentioned treatment system for radioactive waste generated by the production of medical isotopes by accelerators, the low-level radioactive waste sampling box is provided with a low-level radioactive waste return pipe for returning excess liquid to the low-level radioactive waste sampling box, and the low-level radioactive waste return pipe is used as the first chemical reagent addition device;

[0039] The intermediate-level radioactive waste sampling box is provided with an intermediate-level radioactive waste return pipe for returning excess liquid to the intermediate-level radioactive waste sampling box, and the intermediate-level radioactive waste return pipe is used as the second chemical reagent addition device;

[0040] The low-level radioactive waste storage tank and the intermediate-level radioactive waste storage tank are equipped with liquid level monitoring devices and pressure monitoring devices.

[0041] In the above-mentioned treatment system for radioactive waste generated by the production of medical isotopes by accelerators, the low-level radioactive waste treatment unit generated by the separation hot cell further includes an air compressor, which transports the low-level radioactive waste to the low-level radioactive waste sampling box by means of air pressure;

[0042] The intermediate-level radioactive waste treatment unit generated by the separation process further includes an air compressor, which transports the intermediate-level radioactive waste to the intermediate-level radioactive waste sampling box by means of air pressure.

[0043] In the above-mentioned treatment system for radioactive waste generated by the production of medical isotopes by accelerators, the intermediate-level radioactive waste treatment unit generated by the separation process further includes a pressure-controlled ejector connected to the second filter, which is used to transport the gas discharged from the second filter to the waste gas treatment system.

[0044] In the above-mentioned treatment system for radioactive waste liquid generated in the production of medical isotopes by an accelerator, in the low-level radioactive waste liquid treatment unit generated by the separation hot cell, the outlet of the low-level radioactive waste liquid sampling tank is connected to the inlet of the low-level radioactive waste liquid temporary storage tank;

[0045] In the intermediate-level radioactive waste liquid treatment unit generated by the separation process, the outlet of the intermediate-level radioactive waste liquid sampling tank, the waste liquid outlets of the trap and the second filter are connected to the inlet of the intermediate-level radioactive waste liquid temporary storage tank.

[0046] Due to the adoption of the above technical solutions, the present invention has the following beneficial effects:

[0047] (1) The present invention classifies and collects radioactive waste liquid generated in the process of producing medical isotopes by bombarding isotopes with an accelerator from the source. According to different production process steps, it is divided into: accelerator cooling activation water, high-power beam collector cooling activation water, and isotope production target cooling activation water generated during the target bombardment process; separation process: flushing waste liquid, laboratory operation waste liquid, and separation waste liquid. Classifying and collecting radioactive waste liquid is more conducive to waste minimization and cost reduction of treatment.

[0048] (2) The accelerator activation water adopts the method of collecting, temporarily storing, and decaying for treatment to meet the discharge standard of the sewage pipe after release control.

[0049] (3) For the relatively high-level isotope target and beam collector activation water (containing nuclides washed from the target holder or cooling grooves), if it cannot pass the cooling release control, ion exchange treatment needs to be carried out until it is finally purified and meets the discharge standard.

[0050] (4) Low-level radioactive waste liquid such as hot cell flushing and laboratory operations is collected and temporarily stored in the low-level radioactive waste liquid temporary storage tank, and the separation process waste liquid is separately collected in the intermediate-level radioactive waste liquid temporary storage tank. After adjusting the waste liquid to an appropriate alkalinity, the separation process waste liquid and the low-level radioactive waste liquid are respectively sent to the solidification unit after metering, and finally processed into solid waste that meets the disposal requirements, effectively solving the final disposal of the waste liquid at a relatively low construction cost.

[0051] (5) The intermediate-level radioactive waste liquid temporary storage tank generated by the separation process discharges the generated gas to the waste gas treatment system through another pipeline via a trap, a filter, and a compressed air ejector, and finally undergoes high-altitude controlled emission through the field chimney. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is the overall flow chart of the treatment method for radioactive waste liquid generated in the production of medical isotopes by the accelerator of the present invention.

[0053] Figure 2 It is the treatment process flow of accelerator activation water in the specific embodiment of the present invention.

[0054] Figure 3This is the treatment process for the activated wastewater of the isotope production target and beam collector in the specific embodiments of the present invention.

[0055] Figure 4 This is the treatment process for the low-level radioactive waste generated in the separation hot cell and the medium-level radioactive waste generated in the separation process in the specific embodiments of the present invention.

[0056] In the figure, each label is as follows:

[0057] 1 - Classification and collection of radioactive waste liquid; 2 - Monitoring and treatment of radioactive waste liquid; 3 - Discharge of purified waste liquid; 4 - Solidification treatment;

[0058] 100 - Discharge

[0059] 200 - Solidification system; 201 - Inlet of the first activated wastewater; 202 - First activated wastewater collection tank; 203 - First activity sampling and monitoring device; 204 - First valve; 205 - First transfer pump;

[0060] 300 - External transportation; 301 - Inlet of the second activated wastewater; 302 - Second activated wastewater collection tank; 303 - Second activity sampling and monitoring device; 304 - Second valve; 305 - Second transfer pump; 306 - Third valve; 307 - Fourth valve; 308 - First filter; 309 - Ion exchange bed; 310 - Purified water collection tank; 311 - Third activity sampling and monitoring device; 312 - Fifth valve; 313 - Third transfer pump; 314 - Sixth valve; 315 - Seventh valve; 316 - Flowmeter; 317 - Collection of solid waste;

[0061] 400 - Chimney; 401 - Inlet of low-level radioactive waste liquid; 402 - First pre-filter; 403 - Eighth valve; 404 - First air compressor; 405 - Low-level radioactive waste temporary storage tank; 406 - Ninth valve; 407 - Tenth valve; 408 - Low-level radioactive waste sampling box; 409 - Fourth transfer pump; 410 - Low-level radioactive waste metering tank;

[0062] 501 - Inlet of medium-level radioactive waste liquid; 502 - Second pre-filter; 503 - Eleventh valve; 504 - Second air compressor; 505 - Medium-level radioactive waste temporary storage tank; 506 - Twelfth valve; 507 - Trapper; 508 - Second filter; 509 - Medium-level radioactive waste sampling box; 510 - Thirteenth valve; 511 - Fourteenth valve; 512 - Compressed air ejector; 513 - Medium-level radioactive waste metering tank. Specific embodiments

[0063] As mentioned in the background art, the radioactive waste liquid generated in the utilization of nuclear technology, especially in nuclear medicine applications, has a relatively short source-term half-life, few types and amounts of radionuclides, and a low specific activity of radioactivity. The treatment method is relatively simple and can generally decay to the clearance level within 1 year and then be discharged into the industrial sewage pipeline. The radioactive waste liquid generated by nuclear power plants is generally mainly medium and low-level radioactive waste liquid, with a large quantity, few types of radionuclides, and mainly comes from process drain water, floor drain water, and chemical drain water, etc. Currently, the main methods for treating these waste liquids are flocculation precipitation, evaporation, and ion exchange to purify the waste liquid. This method has large investment, a large amount of secondary waste, high energy consumption, and high later operation and maintenance costs. The spent fuel reprocessing stage also has great differences from the source term described in the present invention. It contains more than 300 kinds of fission fragments formed by fission reactions and their decay products, there are many transuranic toxic radionuclides such as various uranium and plutonium, and there is a strong heat release rate and a high radionuclide radioactivity. Therefore, during the reprocessing process, the waste liquid contains various fission products, activation products, corrosion products, extracted uranium, plutonium, transuranic elements formed by neutron capture (such as Np, Am, Cm), cladding materials (such as A1, Mg, Fe, Mo, Zr, etc.), neutron poisons (such as Gd, Cd, B, etc.), chemical reagents introduced during reprocessing (such as NO 3- 、S04 2- 、PO4 3- 、F - 、Na + etc.) and organic impurities, etc. There are dozens of important radionuclides, and the half-life of long-lived radionuclides exceeds one million years. The biological toxicity of many radionuclides is extremely strong and belongs to the extremely toxic or highly toxic category. There are also some volatile or gaseous radionuclides, such as 3 H、 85 Kr、 106 Ru、 131 I、 129 I, etc. Although the half-life of some radionuclides themselves is not very long, the life of their decay products is very long. For example, the half-life of 241 Pu and 241 Am decay to form 237 Np is as long as 2.14×10 6 a. The danger of these waste liquid source terms is much greater than the source term of the present invention.

[0064] The source term of the radioactive waste liquid generated based on the production of medical radioactive isotopes by accelerators (such as Ra-223 and Ac-225 described in the present invention) is very different from the above source terms. The specific activity of the waste liquid after separation is about 10 10 ~10 12 Bq / L, and the types of radioactive elements contained are as many as more than 50, and there are about 300 kinds of radionuclides. The annual output is not large (generally not more than 1m 3 / a). The half-lives of these radionuclides range from a few minutes to thousands of years. Among them, 37.70% have a half-life of less than 1 hour, approximately 14.98% have a half-life greater than or equal to 1 hour and less than 1 day, about 36.44% have a half-life greater than or equal to 1 day and less than 30 days, 10.21% have a half-life greater than or equal to 30 days and less than 1 year, and approximately 0.67% have a half-life greater than 1 year. The characteristics of these main radionuclides are different from those of radionuclides in nuclear medicine applications, nuclear power plants, and the liquid waste of reprocessing plants. Therefore, it is necessary to select a special treatment process method suitable for this liquid waste by combining these characteristics, the physical and chemical characteristics of the liquid waste, the economy of construction, and later operation and maintenance. It can be understood that, similarly, radioactive liquid waste generated based on the production of medical radioisotopes At-211, Ge-68, and / or Cu-67 by accelerators also has the same characteristics.

[0065] The following takes the production of α-medical isotopes ([ 225 Ac and 223 Ra) by bombarding a thorium target with protons as an example to detail the treatment method of the radioactive liquid waste generated by the present invention for the production of medical isotopes by accelerators.

[0066] In a first aspect, the present invention provides a treatment method for radioactive liquid waste generated by the production of medical isotopes by accelerators, including the following steps: S100. Classify and collect the accelerator activation water, isotope production target and beam collector activation water, low-level radioactive liquid waste generated by the separation hot cell, and medium-level radioactive liquid waste generated by the separation process in the radioactive liquid waste generated by bombarding an isotope production target with an accelerator to produce medical isotopes; S200. Treat the accelerator activation water, the isotope production target and beam collector activation water, the low-level radioactive liquid waste generated by the separation hot cell, and the medium-level radioactive liquid waste generated by the separation process respectively as follows: Cool the accelerator activation water and sample and monitor the activity. If it meets the clearance discharge standard, it is discharged after clearance; Cool the isotope production target and beam collector activation water and sample and monitor the activity. If it meets the clearance discharge standard, it is discharged after clearance. If it does not meet the clearance discharge standard, the following treatment is carried out: Filter the liquid waste and then perform ion exchange to obtain a purified liquid; Sample and monitor the activity of the purified liquid. If it meets the clearance discharge standard, it is discharged after clearance or used as a solidification additive liquid; Sample and monitor the pH value of the low-level radioactive liquid waste generated by the separation hot cell, adjust the liquid waste to alkaline by adding chemical reagents, and perform solidification treatment on the adjusted liquid waste; Capture the liquid particles in the gas generated by the medium-level radioactive liquid waste generated by the separation process, filter the captured gas to remove aerosols and water vapor, and input the filtered gas into the waste gas treatment system for controlled discharge; Sample and monitor the pH value of the medium-level radioactive liquid waste, adjust the liquid waste to alkaline by adding chemical reagents, and perform solidification treatment on the adjusted liquid waste. As Figure 1As shown in the figure, it is the overall flow chart of the treatment method for radioactive waste liquid generated by the accelerator in the production of medical isotopes. The classification and collection of radioactive waste liquid 1 is step S100. The monitoring and treatment of radioactive waste liquid 2 is to monitor and treat the classified waste liquid respectively in step S200. The discharge of the purified waste liquid 3 is to discharge the classified waste liquid after purification respectively in step S200. The solidification treatment 4 is to carry out solidification treatment on the classified waste liquid respectively in step S200. The method of the present invention is aimed at the treatment of radioactive waste liquid generated by the production of medical radioactive isotopes based on accelerators. The waste liquid is classified and collected from the source of generation. For example, the low-activation cooling water of the accelerator, the cooling water of the target and the high-power beam collector, the low-level radioactive flushing and chemical hydrophobicity generated in the separation hot cell, the medium-level radioactive process waste liquid generated in the separation process, etc. should be classified and collected from the source, providing a basic guarantee for the subsequent optimized treatment. According to the characteristics of the radionuclides in the waste liquid, a suitable treatment process method is selected, and the waste liquid is treated to the level of off-site transportation with the lowest possible treatment process cost and operating cost, so as to achieve safe treatment and the purpose of not polluting the environment. Finally, it can provide a basic guarantee for the continuous production of isotopes, which can not only meet the needs of continuous production in the field area, simplify the process flow, reduce the construction cost, and facilitate operation, but also meet the requirements of safe discharge of waste liquid or off-site safe transportation, and ensure the continuous production of medical isotopes.

[0067] According to the present invention, the accelerator activation water refers to the cooling water in the magnet being activated during the operation of the accelerator. The radioactive nuclides in this kind of waste water have a short half-life and a low specific activity. During the operation of the accelerator, the transported ions, due to some ions deviating from the center of the beam line and being lost on the transport pipe wall, generate neutrons. The secondary neutrons react with the cooling water in the magnet equipment to generate activated nuclides, mainly including 3 H, 7 Be, 14 C and other nuclides. This kind of waste water is collected into the first activated waste water collection pool. In view of the characteristics of the accelerator cooling activation water, the present invention adopts the method of collecting, temporarily storing and decaying treatment. Specifically, the accelerator activation water is cooled and sampled to monitor the activity, and it is released from control when it meets the release standard. The cooling and activation degree monitoring time of the accelerator activation water is not more than 1 year. Generally, the release standard can be fully met within 1 year, and then it is released from control into the waste water pipeline or reused in the factory. For example, the first monitoring can be carried out when it is cooled for 6 months. Generally, the site of drug production is not necessarily built on the coast. The release specific activity in the monitored water is generally: α does not exceed 1 Bq / L, and β does not exceed 10 Bq / L.

[0068] According to the present invention, the activated water of the isotope production target and beam collector refers to the cooling water from the production target and the beam collector components. Since the beam loss is relatively large at this location and the flow rate of the cooling water is relatively high, in addition to the activated water, there may also be some impurity nuclides such as iron and copper in the waste liquid. The specific activity of the cooling water at this location is relatively high compared to the accelerator-activated water. This type of wastewater is collected in the second activated wastewater collection tank. In view of the characteristics of the activated water of the isotope production target and beam collector, the present invention first adopts the method of collecting, temporarily storing and decay treatment, and then purifies it according to the monitoring results. Specifically, the activated water of the isotope production target and beam collector is cooled and sampled to monitor the activity. If it meets the release standard, it is released. If it does not meet the release standard, the following treatment is carried out: the waste liquid is filtered and then subjected to ion exchange to obtain a purified liquid; the activity of the purified liquid is sampled and monitored. If it meets the release standard, it is released or used as a solidification additive liquid. Among them, the cooling and activity monitoring time of the activated water of the isotope production target and beam collector is 1 year. After 1 year of cooling, if it meets the release standard after sampling and monitoring, it is discharged into the wastewater pipeline or reused within the factory. Generally, the site for general drug production is not necessarily built on the coast. The release specific activity monitored in the water at this location is generally: α does not exceed 1 Bq / L, and β does not exceed 10 Bq / L. Preferably, in the treatment of the activated water of the isotope production target and beam collector, the filtration is to remove oils and particulate matters in the waste liquid. These substances are likely to cause blockage of the ion exchange resin and affect the life of the resin. The filtration accuracy is 50-80 μm; the filtered waste liquid then passes through an ion exchange system. In the ion exchange column, cation exchange resin, anion exchange resin or anion-cation mixed resin can be added to remove free nuclides in the waste liquid, including but not limited to calcium, magnesium, iron, manganese, copper, nitrogen and other ions, so as to remove most of the radioactive nuclides in the cooling activated water. Preferably, the wet solid waste generated by the filtration and the ion exchange is collected and temporarily stored, and transported out for treatment after release. The wet solid waste that cannot be released is solidified.

[0069] According to the present invention, the low-level radioactive waste liquid refers to the waste liquid generated by the flushing of the separation hot cell and each laboratory and chemical hydrophobicity. The low-level radioactive waste liquid mainly comes from the separation hot cell, which is respectively the flushing waste liquid of the separated containers, etc. The nuclide types contained in this waste liquid are all or part of the nuclides in the separation waste liquid. The specific types and activities are uncertain, and the total specific activity does not exceed 10 6 Bq / L. Another part comes from the operation waste liquid in the radiochemistry laboratory. The nuclide types contained in this waste liquid are also temporarily all or part of the nuclides in the separation waste liquid, and the total specific activity does not exceed 10 6Bq / L. The low-level radioactive waste contains a small amount of acidic substances such as sulfuric acid, hydrofluoric acid, and citric acid. This type of radioactive waste is collected in a low-level radioactive waste temporary storage tank. In view of the characteristics of the low-level radioactive waste generated in the separation hot cell, after adjusting the waste liquid to an appropriate alkalinity, the low-level radioactive waste is metered and sent to the solidification unit. Preferably, before sampling and monitoring the pH value of the low-level radioactive waste generated in the separation hot cell, it is filtered to remove particulate impurities, and the wet solid waste generated by the filtration is solidified. Specifically, the filtered filter and impurities can be loaded into a 200L waste barrel and then enter the solidification system for fixation. Preferably, the solidification treatment is cement solidification treatment, and the pH value of the alkali is 8-13. Since the low-level radioactive waste contains a small amount of acidic substances such as sulfuric acid, hydrofluoric acid, and citric acid, it is easy to decompose the calcium hydroxide in the cement hydration product, which is not conducive to setting and curing and reduces the concrete strength. Furthermore, the fixation of radionuclides is not ideal. Therefore, during cement solidification, it is required to be carried out under alkaline conditions, which is more conducive to promoting coagulation and facilitating curing during the solidification process. Preferably, the sample taken for monitoring the pH value of the low-level radioactive waste is refluxed into the low-level radioactive waste generated in the separation hot cell. Preferably, the activity is monitored while monitoring the pH value of the low-level radioactive waste generated in the separation hot cell, for estimating the total radioactivity after solidification.

[0070] The intermediate-level radioactive waste generated by the separation process refers to the waste liquid from the dissolution of the isotope-producing target in the separation hot cell. The intermediate-level radioactive waste is mainly the process radioactive waste generated during the separation process, such as the waste liquid generated during the processes of thorium target dissolution, separation, concentration, and purification. After extracting the target nuclide, the specific activity of the waste liquid is about 10 11Bq / L, containing acidic substances such as sulfuric acid, hydrofluoric acid and citric acid. In each liter of the waste liquid, the chemical components are approximately 0.78 mol / L of nitric acid HNO3, approximately 0.16 mol / L of ammonium sulfate (NH4)2SO4, and approximately 0.03 mol / L of citric acid. The waste liquid contains a large amount of thorium, lanthanide nuclides and other nuclides. This radioactive waste liquid is collected into the intermediate-level radioactive waste temporary storage tank. According to the characteristics of the intermediate-level radioactive waste generated by the separation process, the gas generated by the decay of nuclides in the intermediate-level radioactive waste is treated through a trap and a filter, and then discharged to the exhaust system. After adjusting the intermediate-level radioactive waste to an appropriate alkalinity, the intermediate-level radioactive waste is sent to the solidification unit through a metering tank. Preferably, the waste liquid is first filtered to remove particulate impurities, and the wet solid waste generated by the filtration is subjected to solidification treatment. Preferably, the solidification treatment is cement solidification treatment, and the pH value of the alkali is 8-13. Since the intermediate-level radioactive waste contains acidic substances such as sulfuric acid, hydrofluoric acid and citric acid, it is easy to decompose the calcium hydroxide in the cement hydration product, which is not conducive to setting and curing and reduces the concrete strength, and thus the fixation of radioactive nuclides is not ideal. Therefore, during cement solidification, it is required to be under alkaline conditions, which is more conducive to promoting coagulation and facilitating curing during the solidification process. Preferably, in the treatment of the intermediate-level radioactive waste generated by the separation process, the samples taken for monitoring the acidity and alkalinity of the intermediate-level radioactive waste, the waste liquid generated in the gas trapping step and the filtration step are all refluxed to the intermediate-level radioactive waste storage tank generated by the separation process. Preferably, while monitoring the acidity and alkalinity of the low-level radioactive waste generated in the separation hot cell, the activity is also monitored to estimate the total radioactivity after solidification.

[0071] Among them, the low-level radioactive waste and medium-level radioactive waste are jointly solidified, that is, the low-level radioactive waste generated in the separation hot cell and the medium-level radioactive waste generated in the separation process adopt the same solidification system. The advantages of the joint treatment of low-level and medium-level radioactive waste are mainly as follows: 1. The low-level and medium-level radioactive waste are directly solidified without purification treatment, which can save a large amount of equipment construction and operation costs, and there is no need to consider the treatment of a large number of secondary pollutants; 2. Since the isotope production site is generally selected in a place with convenient transportation and easy to transport, it is generally not located in a coastal or lakeside area. If it is purified to the industrial waste liquid discharge standard, the cost and price are too high; 3. Due to the relatively high specific activity of the medium-level radioactive waste, too much waste liquid cannot be solidified in a 200L solidification barrel. According to the characteristics of the radionuclides described in the present invention, the amount of waste liquid solidified in each barrel generally does not exceed 30L. If the amount of waste liquid is more, it will cause the dose rate on the outer surface of the solidification barrel to be too high. According to the waste disposal acceptance requirements, HIC or other shielding containers are required. Therefore, the supplementary amounts of medium-level waste liquid and low-level radioactive waste can be calculated according to the monitoring data, so that the medium-level waste liquid and low-level radioactive waste can be treated simultaneously; 4. According to the characteristics of the solidification process, the waste volume expansion coefficient is about 3-6. According to the characteristics of the waste liquid volume, the solidified waste generated in one year is about several cubic meters, which is feasible from the aspects of disposal or operation. Therefore, this method is a more suitable method for the treatment of waste liquid generated by accelerator-based isotope production.

[0072] In a second aspect, the present invention provides a treatment system for radioactive waste liquid generated in the production of medical isotopes by an accelerator, comprising: an accelerator activation water unit including a first activated wastewater collection tank and a first activity sampling and monitoring device, the first activity sampling and monitoring device being installed on the first activated wastewater collection tank; an isotope production target and beam collector activation water treatment unit including a second activated wastewater collection tank, a second activity sampling and monitoring device, a third activity sampling and monitoring device, a first filter, an ion exchange bed, and a purified water collection tank, the second activated wastewater collection tank, the first filter, the ion exchange bed, and the purified water collection tank being connected in sequence, the second activity sampling and monitoring device being installed on the second activated wastewater collection tank, and the third activity sampling and detection device being installed on the purified water collection tank; a low-level radioactive waste liquid treatment unit for the separated hot cell, including a first pre-filter, a low-level radioactive waste liquid storage tank, a low-level radioactive waste liquid sampling box, and a first chemical reagent addition device, the first pre-filter being installed on the input pipeline of the low-level radioactive waste liquid storage tank, the low-level radioactive waste liquid sampling box being connected to the sampling port of the low-level radioactive waste liquid storage tank, and the first chemical reagent addition device being connected to the reagent addition port of the low-level radioactive waste liquid storage tank; an intermediate-level radioactive waste liquid treatment unit for the separation process, including a second pre-filter, an intermediate-level radioactive waste liquid storage tank, a trap, a second filter, an intermediate-level radioactive waste liquid sampling box, and a second chemical reagent addition device, the second pre-filter being installed on the input pipeline of the intermediate-level radioactive waste liquid storage tank, the trap outlet of the intermediate-level radioactive waste liquid storage tank being connected to the trap, the trap being connected to the second filter, the sampling outlet of the intermediate-level radioactive waste liquid storage tank being connected to the intermediate-level radioactive waste liquid sampling box, and the second chemical reagent addition device being connected to the reagent addition port of the intermediate-level radioactive waste liquid storage tank; a solidification treatment system, the waste liquid outlet of the purified water collection tank being connected to the solidification treatment system and a flowmeter being provided on the connecting pipeline, the waste liquid outlet of the low-level radioactive waste liquid storage tank being connected to the solidification treatment system and a low-level radioactive waste liquid metering tank being provided on the connecting pipeline, and the waste liquid outlet of the intermediate-level radioactive waste liquid storage tank being connected to the solidification treatment system and an intermediate-level radioactive waste liquid metering tank being provided on the connecting pipeline.

[0073] In the above embodiments, specifically, as Figure 2As shown, a first activation wastewater collection tank 202 is provided with a first activation wastewater inlet 201 for transporting accelerator activation wastewater into the first activation wastewater collection tank 202. The volume of the first activation wastewater collection tank 202 is not less than the volume when all the activation water is discharged. A first activity sampling and monitoring device 203 is installed on the first activation wastewater collection tank 202, and a first valve 204 and a first transfer pump 205 are provided on the output pipeline of the first activation wastewater collection tank 202. During use, after the accelerator activation wastewater is cooled for a period of time (generally several months and not exceeding one year), the first activity sampling and monitoring device 203 samples and monitors the wastewater in the first activation wastewater collection tank 202. If the release control standard is met, the first valve 204 can be opened and then the wastewater is discharged through the first transfer pump 205, such as discharging it into an industrial wastewater pipeline or for in-plant reuse, etc.; if the release control standard is not met, it continues to be cooled until the release control is achieved.

[0074] In the above embodiments, specifically, such as Figure 3As shown in the figure, the second activated wastewater collection tank 302 is provided with a second activated wastewater inlet 301. The second activity sampling and monitoring device 303 is installed on the second activated wastewater collection tank 302. A second valve 304 and a second transfer pump 305 are provided on the output pipeline of the second activated wastewater collection tank 302. The output pipeline of the second activated wastewater collection tank 302 is divided into two paths. One path is provided with a fourth valve 307 for external discharge 100. The other path is successively provided with a third valve 306, a first filter 308, an ion exchange bed 309, and a purified water collection tank 310. The outlet of the first filter 308 is connected to the inlet of the ion exchange bed 309. The outlet of the ion exchange bed 309 is connected to the inlet of the purified water collection tank 310. The purified water collection tank 310 is provided with a third activity sampling and monitoring device 311. A fifth valve 312 and a third transfer pump 313 are provided on the output pipeline of the purified water collection tank 310 and are again divided into two paths. One path is provided with a sixth valve 314 for external discharge 100. The other path is successively provided with a seventh valve 315 and a flow meter 316 and enters the solidification system 200. During use, the cooling and activated wastewater of the target and the high-power beam collector is transported and collected through the second activated wastewater inlet 301 to the second activated wastewater collection tank 302. After the wastewater is cooled for a period of time (generally several months, not exceeding one year), the second activity sampling and monitoring device 303 is used to sample and monitor the wastewater in the second activated wastewater collection tank 302. If the release control standard is met, the second valve 304 and the fourth valve 307 can be opened, and the third valve 306 can be closed. Then, it is discharged externally 100 through the waste liquid transfer pump, that is, the second transfer pump 305, for example, discharged to the industrial wastewater pipeline or reused within the site, etc.; if the release control cannot be achieved after long-term monitoring (more than 1 year), the second valve 304 and the third valve 306 need to be opened, the fourth valve 307 is closed, and the waste liquid is sent to the first filter 308 through the second transfer pump 305. This filter is used to remove oils, colloids, particulate matters, etc. The filtered waste liquid enters the ion exchange bed 309. The ion exchange bed can be an anion bed, a cation bed, or a mixed anion and cation bed, etc. The purified liquid after ion exchange is temporarily stored in the purified water collection tank 310, and the third activity sampling and monitoring device 311 is used for sampling and monitoring. If the release control discharge standard is met, the fifth valve 312 and the sixth valve 314 are opened, the seventh valve 315 is closed, and the purified liquid is discharged externally 100 through the third transfer pump 313, for example, discharged to the industrial wastewater pipeline or reused within the plant; or the fifth valve 312 and the seventh valve 315 are opened, the sixth valve 314 is closed, and the purified liquid is discharged to the dosing tank 316 through the third transfer pump 313 and then used as an additive liquid for the solidification system 200. The wet solid wastes generated by the first filter 308 and the ion exchange bed 309 are classified and collected and temporarily stored for solid waste collection 317. After release control, they are transported out 300. If the waste that cannot be released needs to be transported to the solidification system 200 for solidification and then transported out for treatment.

[0075] In the above embodiments, preferably, a low-level waste liquid reflux pipe for returning excess liquid to the low-level waste liquid sampling tank is provided on the low-level waste liquid sampling tank, and the low-level waste liquid reflux pipe serves as the first chemical reagent adding device; a medium-level waste liquid reflux pipe for returning excess liquid to the medium-level waste liquid sampling tank is provided on the medium-level waste liquid sampling tank, and the medium-level waste liquid reflux pipe serves as the second chemical reagent adding device; a liquid level monitoring device and a pressure monitoring device are installed on the low-level waste liquid storage tank and the medium-level waste liquid storage tank.

[0076] In the above embodiments, preferably, the low-level waste liquid treatment unit generated by the separation hot cell further includes an air compressor for transporting the low-level waste liquid to the low-level waste liquid sampling tank by means of air pressure; the medium-level waste liquid treatment unit generated by the separation process further includes an air compressor for transporting the medium-level waste liquid to the medium-level waste liquid sampling tank by means of air pressure.

[0077] In the above embodiments, preferably, the medium-level waste liquid treatment unit generated by the separation process further includes a pressure-controlled ejector for transporting the gas output by the second filter to the exhaust system.

[0078] In the above embodiments, preferably, in the low-level waste liquid treatment unit generated by the separation hot cell, the outlet of the low-level waste liquid sampling tank is connected to the inlet of the low-level waste liquid storage tank; in the medium-level waste liquid treatment unit generated by the separation process, the outlet of the medium-level waste liquid sampling tank, the waste liquid outlets of the trap and the second filter are connected to the inlet of the medium-level waste liquid storage tank.

[0079] In the above embodiments, specifically, as Figure 4As shown, in the low-level radioactive waste treatment unit generated by the separated hot cell, on the input pipeline of the low-level radioactive waste storage tank 405, there are successively arranged a low-level radioactive waste inlet 401, a first pre-filter 402, and an eighth valve 403. The main function of the pre-filter is to filter particulate impurities and the like in the liquid to avoid precipitation and accumulation in the storage tank. The low-level radioactive waste storage tank 405 is equipped with monitoring devices such as liquid level monitoring and pressure monitoring. The low-level radioactive waste sampling tank 408 is connected to the sampling port of the low-level radioactive waste storage tank 405, and a tenth valve 407 is arranged on the connecting pipeline. The waste liquid in the low-level radioactive waste storage tank 405 is transported to the low-level radioactive waste sampling tank 408 by the first air compressor 404. The waste liquid outlet of the low-level radioactive waste sampling tank 408 is connected to the low-level radioactive waste inlet 401, and the output pipeline of the waste liquid outlet of the low-level radioactive waste sampling tank 408 can be specifically arranged between the first pre-filter 402 and the eighth valve 403. The low-level radioactive waste sampling tank 408 is provided with a low-level radioactive waste return pipe (not shown in the figure) for returning the excess liquid to the low-level radioactive waste sampling tank, and the low-level radioactive waste return pipe serves as the first chemical reagent addition device. On the waste liquid output pipeline of the low-level radioactive waste storage tank 405, there are successively arranged a ninth valve 406, a fourth transfer pump 409, and a low-level radioactive waste metering tank 410. In use, the low-level radioactive waste enters the low-level radioactive waste storage tank 405 through the low-level radioactive waste inlet 401 and passes through the first pre-filter 402 and then through the eighth valve 403. Before the waste liquid solidification treatment, it is necessary to monitor the activity characteristics and the chemical characteristics of the waste. First, open the tenth valve 407, close the eighth valve 403 and the ninth valve 406, and use the air pressure of the first air compressor 404 to transport the waste liquid to the low-level radioactive waste sampling tank 408 to monitor the activity and chemical properties of the radioactive waste liquid. The activity is used to estimate the total radioactivity after solidification, and the reference chemical characteristics are mainly used to adjust the acidity and alkalinity of the waste liquid. Add chemical substances to enter the low-level radioactive waste storage tank 405 along the sampling tank return port to make the waste liquid have an appropriate alkalinity. When treating the waste liquid, it is necessary to close the eighth valve 403 and the tenth valve 407, open the ninth valve 406, and the liquid is sent to the low-level radioactive waste metering tank 410 by the fourth transfer pump 409, and then enters the solidification system 200 to be solidified together with the intermediate-level radioactive waste. The wet solid waste generated by the first filter 402 is finally sent to the solidification system 200 for solidification treatment.

[0080] In the above embodiment, specifically, such as Figure 4As shown in the figure, in the intermediate-level radioactive waste treatment unit generated by the separation process, on the input pipeline of the intermediate-level radioactive waste storage tank 505, there are successively an intermediate-level radioactive waste inlet 501, a second pre-filter 502, and an eleventh valve 503. The main function of the pre-filter is to filter out particulate impurities and the like in the liquid to avoid precipitation and accumulation in the storage tank. The intermediate-level radioactive waste storage tank 505 is equipped with monitoring devices such as liquid level monitoring and pressure monitoring. On the gas output pipeline of the intermediate-level radioactive waste storage tank 505, there are successively a twelfth valve 506, a trap 507, and a second filter 508. The main function of the trap 507 is to collect liquid particles and the like mixed in the gas. The second filter 508 is mainly used to collect aerosols and water vapor, etc. There is a pressure-controlled ejector 512 on the output pipeline of the second filter, which is used to transport the filtered gas to the exhaust system (such as a chimney). The intermediate-level radioactive waste sampling box 509 is connected to the sampling port of the intermediate-level radioactive waste storage tank 505, and a fourteenth valve 511 is provided on the connecting pipeline. The waste liquid in the intermediate-level radioactive waste storage tank 505 is transported to the intermediate-level radioactive waste sampling box 509 by the second air compressor 504. The waste liquid outlet of the intermediate-level radioactive waste sampling box 509, the waste liquid outlet of the second filter 508, and the waste liquid outlet of the trap 507 are connected to the inlet of the intermediate-level radioactive waste storage tank 505, specifically, it can be set between the second pre-filter 502 and the eleventh valve 503 through the same output pipeline. There is an intermediate-level radioactive waste return pipe (the arrow line in front of the straight valve 503 of 509 in the figure) on the intermediate-level radioactive waste sampling box 509 for returning the excess liquid to the intermediate-level radioactive waste storage tank 505, and the intermediate-level radioactive waste return pipe is used as the second chemical reagent addition device. On the waste liquid output pipeline of the intermediate-level radioactive waste storage tank 505, there are successively a thirteenth valve 510 and an intermediate-level radioactive waste metering tank 513. During use, the intermediate-level radioactive waste enters the intermediate-level radioactive waste storage tank 505 through the intermediate-level radioactive waste inlet 501, passes through the second pre-filter 502, and then passes through the eleventh valve 503. The intermediate-level radioactive waste storage tank 505 has three outlets: during storage, the eleventh valve 503, the thirteenth valve 510, and the fourteenth valve 511 are closed, and the twelfth valve 506 is opened. The gas generated by the decay of nuclides in the storage tank, mixed with liquid particles, aerosols, water vapor, etc., first enters the trap 507 through the exhaled exhaust gas to remove liquid impurities and part of the water vapor, and then passes through the second filter 508 to remove the aerosol nuclides and water vapor in the gas. Finally, it enters the chimney 400 through the pressure-controlled ejector 512 for controlled emission. The pressure-controlled ejector 512 is mainly used to seal the radioactive environment and improve the pressure control effect. Part of the liquid generated in the trap 507 and the second filter 508 is collected into the intermediate-level radioactive waste storage tank 505 through the liquid return pipe.Before the liquid waste solidification treatment, it is necessary to monitor the activity characteristics and chemical characteristics of the waste. First, open the fourteenth valve 511, close the eleventh valve 503, the twelfth valve 506 and the thirteenth valve 510. Use the second air compressor 504 to convey the liquid waste to the intermediate-level radioactive liquid waste sampling tank 509 by means of compressed air to monitor the activity and chemical properties of the radioactive liquid waste. The activity is used to estimate the total radioactivity after solidification, and the reference chemical characteristics are mainly used to adjust the pH value of the liquid waste. Add chemical substances to enter the intermediate-level radioactive liquid waste storage tank 505 along the sampling tank reflux port to make the liquid waste have an appropriate alkalinity. When treating the liquid waste, it is necessary to close the eleventh valve 503, the twelfth valve 506 and the fourteenth valve 511, open the thirteenth valve 510, operate the second air compressor 504, and convey the intermediate-level radioactive liquid waste to the intermediate-level radioactive liquid waste metering tank 513 by means of compressed air, and then enter the solidification system 200 to be solidified together with the low-level radioactive liquid waste. The wet solid waste generated by the filter is finally sent to the solidification system 200 for solidification treatment.

[0081] To sum up, the present invention classifies and collects the radioactive liquid waste generated by the accelerator for the production of medical isotopes, and separately treats the accelerator cooling and activation water, the isotope production target and the high-power beam collector cooling and activation water, the low-level radioactive liquid waste generated by the separation hot cell, and the intermediate-level radioactive liquid waste generated by the separation process. The accelerator cooling and activation water adopts the method of collecting, temporarily storing and decaying treatment. When it meets the release discharge standard, it is released. The activation water of the isotope production target and the beam collector first adopts the method of collecting, temporarily storing and decaying treatment. When it meets the release discharge standard, it is released. If it does not meet the release discharge standard, it is purified by filtration and ion exchange, and then discharged after reaching the standard. For the low-level radioactive liquid waste generated by the separation hot cell, sample and monitor its pH value, and adjust the liquid waste to neutral or weakly acidic by adding chemical reagents, and then carry out solidification treatment on the adjusted liquid waste. For the intermediate-level radioactive liquid waste generated by the separation process, capture and filter the generated gas and then input it into the waste gas treatment system and finally discharge it through the chimney under control; sample and monitor the pH value of the intermediate-level radioactive liquid waste, adjust the liquid waste to an appropriate alkalinity by adding chemical reagents, and carry out solidification treatment on the adjusted liquid waste. In the liquid waste treatment process route, the basic principles of simple and effective technology, mature and reliable equipment, meeting the special requirements of the project, being conducive to the further treatment and disposal of waste without adding new waste, etc. are implemented. The waste minimization management concept is mainly realized through source control, reasonable classification and selection of reasonable treatment processes, and the operation is convenient and simple without adding too much construction cost.

[0082] The present invention has been described in detail above. For those skilled in the art, without departing from the spirit and scope of the present invention, the present invention can be implemented within a relatively wide range under equivalent parameters, concentrations, and conditions. Although specific embodiments of the present invention are given, it should be understood that the present invention can be further improved. In short, according to the principle of the present invention, this application intends to cover any modifications, uses, or improvements to the present invention, including changes made using conventional techniques known in the art that depart from the scope disclosed in this application.

Claims

1. A method for treating radioactive waste liquid generated by accelerator production of medical isotopes, characterized in that: The steps include: S100. Classify and collect the radioactive waste liquid generated by accelerator bombardment of isotope production targets to produce medical isotopes, including accelerator activated water, isotope production target and beam collector activated water, low-level waste liquid generated by the separation hot cell, and intermediate-level waste liquid generated by the separation process; S200, the accelerator activated water, the isotope production target and beam collector activated water, the low-level waste liquid generated by the separation hot cell, and the intermediate-level waste liquid generated by the separation process are treated as follows: Cooling the activated water in the accelerator and taking samples to monitor the activity, and releasing the controlled discharge when the controlled discharge standards are met; Cooling the activated water of the isotope generation target and the beam collector and sampling to monitor the activity; if the controlled emission standards are met, the activated water is released for controlled emission; if the controlled emission standards are not met, the activated water is treated as follows: filtering the activated water of the isotope generation target and the beam collector and performing ion exchange to obtain a purified liquid; sampling to monitor the activity of the purified liquid; if the controlled emission standards are met, the activated water is released for controlled emission or used as a solidification additive; Sampling and monitoring the pH of the low-level waste liquid generated by the separation hot chamber, adjusting the pH of the low-level waste liquid generated by the separation hot chamber to alkaline by adding chemical reagents, and using the adjusted low-level waste liquid generated by the separation hot chamber as an additive for solidifying the intermediate-level waste liquid generated by the separation process; The liquid particles in the gas generated by the intermediate-level radioactive waste liquid produced by the separation process are captured, the captured gas is filtered to remove aerosols and water vapor, and the filtered gas is input into the exhaust system for controlled discharge; the pH value of the intermediate-level radioactive waste liquid produced by the separation process is sampled and monitored, the intermediate-level radioactive waste liquid produced by the separation process is regulated to alkaline by adding chemical reagents, and the intermediate-level radioactive waste liquid produced by the separation process after the regulation is solidified.

2. The method for treating radioactive waste liquid generated by accelerator production of medical isotopes according to claim 1, characterized in that: The medical isotopes are 225 Ac, 223 Ra, 211 At 68 Gehe 67 At least one of Cu.

3. The method for treating radioactive waste liquid generated by accelerator production of medical isotopes according to claim 1 or 2, characterized in that: During the treatment of the accelerator activated water, the cooling and activity monitoring time of the accelerator activated water shall not exceed 1 year; During the treatment of the activated water for the isotope production target and the beam collector, the time for cooling the activated water for the isotope production target and the beam collector and monitoring the activation degree is 1 year.

4. The method for treating radioactive waste liquid generated by accelerator production of medical isotopes according to claim 3, characterized in that: In the treatment of the activated water of the isotope production target and the beam collector, the wet solid wastes generated by the filtration and the ion exchange are collected and temporarily stored, and are transported out after being released from control. The wet solid wastes that cannot be released from control are solidified.

5. The method for treating radioactive waste liquid generated by accelerator production of medical isotopes according to claim 4, characterized in that: In the treatment of the low-level waste liquid generated by the separation hot chamber, the low-level waste liquid generated by the separation hot chamber is filtered to remove particulate impurities before sampling and monitoring the pH value, and the wet solid waste generated by the filtration is solidified; During the treatment of the low-level waste liquid generated by the separation hot chamber, the activity of the low-level waste liquid generated by the separation hot chamber is monitored while the pH value is monitored, so as to estimate the total radioactivity after solidification; The solidification treatment is cement solidification treatment, and the alkaline pH value in the treatment of the low-level waste liquid generated by the separation hot chamber is 8-13; In the treatment of the low-level waste liquid generated by the separation hot chamber, the sample taken for monitoring the pH value of the low-level waste liquid is refluxed into the low-level waste liquid generated by the separation hot chamber; The treatment of the intermediate-level radioactive waste liquid generated by the separation process further includes filtering the intermediate-level radioactive waste liquid to remove particulate impurities, and solidifying the wet-solid waste generated by the filtration; In the treatment of the intermediate-level radioactive waste liquid generated by the separation process, the activity of the intermediate-level radioactive waste liquid generated by the separation hot cell is monitored while the pH value is monitored, so as to estimate the total radioactivity after solidification; The solidification treatment is cement solidification treatment, and the alkaline pH value in the treatment of the intermediate-level waste liquid generated by the separation process is 8-13; The low-level waste liquid generated by the separation hot chamber and the intermediate-level waste liquid generated by the separation process are jointly subjected to the solidification treatment.

6. A system for treating radioactive waste liquid generated by accelerator production of medical isotopes, characterized in that: The processing system is used in the processing method according to any one of claims 1 to 5, comprising: The accelerator activated water unit comprises a first activated wastewater collection tank and a first activity sampling and monitoring device, wherein the first activity sampling and monitoring device is installed on the first activated wastewater collection tank; An isotope production target and beam collector activated water treatment unit comprises a second activated wastewater collection tank, a second activation sampling and monitoring device, a third activity sampling and monitoring device, a first filter, an ion exchange bed, and a clean water collection tank, wherein the second activated wastewater collection tank, the first filter, the ion exchange bed, and the clean water collection tank are connected in sequence, the second activity sampling and monitoring device is installed in the second activated wastewater collection tank, and the third activity sampling and detection device is installed on the clean water collection tank; The low-level waste liquid treatment unit generated by the separation hot cell includes a first pre-filter, a low-level waste liquid temporary storage tank, a low-level waste liquid sampling box, and a first chemical reagent adding device. The first pre-filter is installed on the input pipeline of the low-level waste liquid temporary storage tank, the low-level waste liquid sampling box is connected to the sampling port of the low-level waste liquid temporary storage tank, and the first chemical reagent adding device is connected to the reagent adding port of the low-level waste liquid temporary storage tank. The intermediate-level radioactive waste liquid treatment unit generated by the separation process includes a second prefilter, an intermediate-level radioactive waste liquid temporary storage tank, a trap, a second filter, an intermediate-level radioactive waste liquid sampling box, and a second chemical reagent addition device. The second prefilter is installed on the input pipeline of the intermediate-level radioactive waste liquid temporary storage tank, the exhaust outlet of the intermediate-level radioactive waste liquid temporary storage tank is connected to the trap, the trap is connected to the second filter, the sampling outlet of the intermediate-level radioactive waste liquid temporary storage tank is connected to the intermediate-level radioactive waste liquid sampling box, and the second chemical reagent addition device is connected to the reagent addition port of the intermediate-level radioactive waste liquid temporary storage tank; The solidification treatment system comprises the following: the waste liquid outlet of the clean water collection tank is connected to the solidification treatment system and a flow meter is provided on the connecting pipeline; the waste liquid outlet of the low-level waste liquid storage tank is connected to the solidification treatment system and a low-level waste liquid metering tank is provided on the connecting pipeline; the waste liquid outlet of the intermediate-level waste liquid storage tank is connected to the solidification treatment system and a flow metering tank is provided on the connecting pipeline.

7. The system for treating radioactive liquid waste generated by accelerator production of medical isotopes according to claim 6, characterized in that: The low-level waste liquid sampling box is provided with a low-level waste liquid return pipe for returning excess liquid to the low-level waste liquid sampling box, and the low-level waste liquid return pipe serves as the first chemical reagent adding device; The intermediate-level radioactive waste liquid sampling box is provided with an intermediate-level radioactive waste liquid reflux pipe for returning excess liquid to the intermediate-level radioactive waste liquid sampling box, and the intermediate-level radioactive waste liquid reflux pipe serves as the second chemical reagent adding device; The low-level waste liquid temporary storage tank and the intermediate-level waste liquid temporary storage tank are equipped with a liquid level monitoring device and a pressure monitoring device.

8. The system for treating radioactive liquid waste generated by accelerator production of medical isotopes according to claim 7, characterized in that: The low-level waste liquid treatment unit generated by the separation hot chamber also includes an air compressor, which transports the low-level waste liquid to the low-level waste liquid sampling box by air compression; The intermediate-level radioactive waste liquid treatment unit generated by the separation process also includes an air compressor, which transports the intermediate-level radioactive waste liquid to the intermediate-level radioactive waste liquid sampling box through air compression.

9. The system for treating radioactive liquid waste generated by accelerator production of medical isotopes according to claim 8, characterized in that: The intermediate-level radioactive waste liquid treatment unit generated by the separation process further includes a pressure-controlled ejector connected to the second filter, for conveying the gas discharged from the second filter to the waste gas treatment system.

10. The system for treating radioactive waste liquid generated by accelerator production of medical isotopes according to claim 9, characterized in that: In the low-level waste liquid processing unit generated by the separation hot chamber, the outlet of the low-level waste liquid sampling box is connected to the inlet of the low-level waste liquid temporary storage tank; In the intermediate-level radioactive waste liquid treatment unit generated by the separation process, the outlet of the intermediate-level radioactive waste liquid sampling box, the waste liquid outlets of the collector and the second filter are connected to the inlet of the intermediate-level radioactive waste liquid temporary storage tank.

Images