A small flux radioactive powder product preparation system

Abstract

This invention discloses a low-throughput radioactive powder product preparation system, comprising a glove box, a continuous precipitation reactor, a filtration device, a continuous drying and calcining furnace, and an automatic sampling device. The continuous precipitation reactor, the filtration device, the continuous drying and calcining furnace, and the automatic sampling device are all integrated within the glove box. The continuous precipitation reactor receives the raw material liquid and causes a precipitation reaction to generate oxalate precipitate. The filtration device is connected to the continuous precipitation reactor. The continuous drying and calcining furnace is connected to the filtration device. The automatic sampling device is connected to the continuous precipitation reactor, the filtration device, and the continuous drying and calcining furnace, respectively. This invention features a highly integrated system with low cost and easy maintenance. It allows for sampling and analysis, and the low-throughput preparation scale facilitates process parameter optimization. It can prepare various types and specifications of radioactive powder products. Furthermore, it allows for radioactive experimental research, such as process parameter verification, thereby guiding parameter control in industrial-scale systems.

Description

Technical Field

[0001] This invention belongs to the field of nuclear engineering technology, specifically relating to a low-throughput radioactive powder product preparation system. Background Technology

[0002] Radioactive powders have important applications in medical, industrial, and energy fields, and their preparation is a key step in realizing the nuclear fuel cycle. The preparation of radioactive powders involves processes such as precipitation, filtration, and drying / calcination to convert radioactive elements from a liquid state into a powder state. Powdered products are easier to store, transport, and apply. Radioactive powder preparation processes can be divided into batch and continuous processes. Continuous preparation processes have advantages such as high production capacity, low radiation hazard, and compact footprint. The continuous powder preparation process includes three key steps: continuous precipitation, continuous filtration, and continuous drying / calcination. Continuous precipitation involves continuously adding nitrate and oxalic acid solutions to a precipitation reactor to continuously generate oxalate precipitate slurry. Continuous filtration involves filtering the oxalate precipitate slurry to obtain an oxalate filter cake. Continuous drying / calcination involves heating and dehydrating the oxalate filter cake, continuously converting it into oxide powder products.

[0003] Currently, industrial-scale production of radioactive powders requires significant investment in construction and production costs, and maintenance is difficult. Furthermore, industrial-scale production of powder products is limited in variety and specifications, making it difficult to produce radioactive powder products with different properties (such as particle size distribution) by adjusting process conditions. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the above-mentioned shortcomings of the existing technology by providing a low-throughput radioactive powder product preparation system that is highly integrated, low-cost, easy to maintain, capable of sampling and analysis and facilitating process parameter optimization. It can prepare various types and specifications of radioactive powder products, and at the same time, it can also conduct radioactive experimental research such as process parameter verification, thereby guiding the parameter control of industrial-scale systems.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is:

[0006] This invention provides a low-throughput radioactive powder product preparation system, comprising a glove box, a continuous precipitation reactor, a filtration device, a continuous drying and calcining furnace, and an automatic sampling device, wherein the continuous precipitation reactor, the filtration device, the continuous drying and calcining furnace, and the automatic sampling device are all integrated within the glove box;

[0007] The continuous precipitation reactor is used to receive the raw material liquid and carry it to a precipitation reaction to generate oxalate precipitate.

[0008] The filtration device is connected to the continuous sedimentation reactor and is used to filter the liquid after the sedimentation reaction to separate the oxalate filter cake.

[0009] The continuous drying and roasting furnace is connected to the filtration device and is used to dry and roast the separated oxalate filter cake to obtain a radioactive powder product.

[0010] The automatic sampling device is connected to the continuous sedimentation reactor, the filtration device, and the continuous drying and calcining furnace, respectively, and is used to sample the materials processed by the continuous sedimentation reactor, the filtration device, and the continuous drying and calcining furnace, so as to analyze and adjust the process parameters of the continuous sedimentation reactor, the filtration device, and the continuous drying and calcining furnace in a timely manner to obtain radioactive powder products of different types and specifications.

[0011] Optionally, the system also includes a raw material receiving tank and an oxalic acid storage tank. The raw material receiving tank is connected to the continuous precipitation reactor and integrated into the glove box, and is used to provide nitrate solution as raw material to the continuous precipitation reactor. The oxalic acid storage tank is connected to the continuous precipitation reactor and is used to provide oxalic acid solution to the continuous precipitation reactor, so that it can undergo the precipitation reaction with the nitrate solution provided by the raw material receiving tank.

[0012] Optionally, both the raw material receiving tank and the continuous sedimentation reactor are covered with a localized radiation protection shielding layer.

[0013] Optionally, the system also includes a liquid self-suction device, which is connected to the raw material liquid receiving tank and is used to transport the nitrate liquid generated in the upstream process of the post-treatment plant to the raw material liquid receiving tank.

[0014] Optionally, the system also includes a prefilled liquid storage tank, which is connected to the continuous sedimentation reactor and is used to provide prefilled liquid to the continuous sedimentation reactor. The prefilled liquid is a mixture of 0.01~1 mol / L oxalic acid and 1~6 mol / L nitric acid solution.

[0015] Optionally, the system also includes a liquid return device, which is connected to the continuous sedimentation reactor and the filtration device respectively, for raw material recovery and waste liquid treatment.

[0016] Optionally, the filtration device is an external filter hub-type filter, which has five functional stations inside: filtration, washing, suction, backflushing and unloading, and filter plate regeneration, and has no less than five filter plates inside.

[0017] Optionally, the system further includes one or more of a vacuum device, a compressed air device, a washing liquid storage tank, and a regenerated liquid storage tank; the vacuum device is connected to the filtration device and is used to provide the filtration device with the negative pressure required for the filtration and suction processes; the washing liquid storage tank is connected to the filtration device and is used to provide the filtration device with the washing liquid required for the washing process; the compressed air device is connected to the filtration device and is used to provide the filtration device with the pulse pressure required for the backflushing and unloading process; the regenerated liquid storage tank is connected to the filtration device and is used to provide the filtration device with the regenerated liquid required for the washing process.

[0018] Optionally, the glove box is provided with a liquid handling area and a powder handling area, which are located at opposite ends of the glove box. The continuous sedimentation reactor and the filtration device are located in the liquid handling area, and the continuous drying and calcining furnace and the automatic sampling device are located in the powder handling area. The liquid handling area and the powder handling area are provided with a slope gradient.

[0019] Optionally, the glove box is equipped with an exhaust duct, which has multiple branch pipes. The outlets of each branch pipe are located near the continuous sedimentation reactor, the filter device, the continuous drying and roasting furnace, and the raw material liquid receiving tank, and are equipped with a flow regulation mechanism.

[0020] Beneficial effects:

[0021] The low-throughput radioactive powder product preparation system of this invention integrates a continuous precipitation reactor, a filtration device, a continuous drying and calcining furnace, and an automatic sampling device all within a glove box, resulting in a highly integrated structure. This system offers low throughput, small scale, low cost, easy maintenance, and easy adjustment of process operating parameters. It can prepare various types and specifications of radioactive powder products, and the process is simple, safe, reliable, and highly operable. Furthermore, it allows for radioactive experimental research, such as process parameter verification, providing a continuous process flow and key process operating range parameters for radioactive powder product preparation in reprocessing plants. This data can also be used as a reference for similar operating conditions, guiding parameter control in industrial-scale systems and ensuring the smooth production of radioactive powder products. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a low-throughput radioactive powder product preparation system in an embodiment of the present invention.

[0023] In the diagram: 1-Glove box; 2-Self-suction device for feed liquid; 3-Raw material receiving tank; 4-Continuous sedimentation reactor; 5-Feed liquid return device; 6-Prefilled liquid storage tank; 7-Oxalic acid storage tank; 8-Filter device; 9-Washing liquid storage tank; 10-Regenerated liquid storage tank; 11-Continuous drying and roasting furnace; 12-Filtration receiving tank; 13-Product; 14-Vacuum device; 15-Compressed air device; 16-First quantitative conveying device; 17-Second quantitative conveying device; 18-Third quantitative conveying device; 19-Fourth quantitative conveying device; 20-Fifth quantitative conveying device; 21-Sediment slurry sampling port; 22-Filtration sampling port; 23-Filter cake sampling port; 24-Oxide powder product sampling port; 25-Automatic sampling device. Detailed Implementation

[0024] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0025] In the description of this invention, it should be noted that the terms "above" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience and simplification of the description and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0026] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connection," "setting," "installation," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] It is understood that, without conflict, the various embodiments and features in the embodiments of the present invention can be combined with each other.

[0029] It is understood that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, while the parts unrelated to the present invention are not shown in the drawings.

[0030] To address the problems of existing technologies requiring significant investment in construction and production, high maintenance difficulty, limited product variety and specifications, and difficulty in producing radioactive powder products with different properties by adjusting process conditions, this invention provides a low-throughput radioactive powder product preparation system. The system includes a glove box, a continuous precipitation reactor, a filtration device, a continuous drying and calcining furnace, and an automatic sampling device, all integrated within the glove box. The continuous precipitation reactor receives the raw material liquid and induces a precipitation reaction to generate oxalate precipitate. The filtration device, connected to the continuous precipitation reactor, filters the liquid after the precipitation reaction to separate the oxalate filter cake. The continuous drying and calcining furnace, connected to the filtration device, calcines the separated oxalate filter cake to obtain the radioactive powder product. The automatic sampling device, connected to the continuous precipitation reactor, filtration device, and continuous drying and calcining furnace respectively, samples the materials processed by these processes to analyze and adjust the process parameters of the reactor, filtration device, and furnace in a timely manner, thereby obtaining radioactive powder products of different types and specifications.

[0031] The low-throughput radioactive powder product preparation system of the present invention is highly integrated, low-cost, easy to maintain, and can perform sampling analysis. The low-throughput preparation scale facilitates the optimization of process parameters and can prepare various types and specifications of radioactive powder products. At the same time, it can also conduct radioactive experimental research such as process parameter verification, thereby guiding the parameter control of industrial-scale systems.

[0032] Example 1

[0033] like Figure 1 As shown, this embodiment discloses a low-throughput radioactive powder product preparation system, including a glove box 1, a continuous precipitation reactor 4, a filter device 8, a continuous drying and calcining furnace 11, and an automatic sampling device 25. The glove box 1 is equipped with a radiation protection shielding layer made of carbon steel. The continuous precipitation reactor 4, the filter device 8, the continuous drying and calcining furnace 11, and the automatic sampling device 25 are all integrated within the glove box 1. Through this high degree of integration within the glove box 1, complex physicochemical changes involving multiple phases, such as solids and liquids, can be performed simultaneously within a single chamber.

[0034] The continuous sedimentation reactor 4 is a continuous crystallizer in the form of mixed suspension mixed product discharge (MSMPR). The bottom of the reactor is equipped with a magnetic stir bar, which can stir the feed liquid in the continuous sedimentation reactor 4 by applying an external magnetic field. The stirring speed is 200~800 rpm. It is used to receive the raw material liquid and make it undergo a precipitation reaction to generate oxalate precipitate.

[0035] The filtration device 8 is connected to the continuous sedimentation reactor 4 and is used to filter the liquid after the sedimentation reaction to separate the oxalate filter cake.

[0036] The continuous drying and roasting furnace 11 is connected to the filter device 8 and is used to dry and roast the separated oxalate filter cake to obtain oxide powder product, i.e., radioactive powder product 13.

[0037] Automatic sampling device 25 is connected to continuous sedimentation reactor 4, filter device 8, and continuous drying and roasting furnace 11 respectively. It is used to sample the materials processed by continuous sedimentation reactor 4, filter device 8, and continuous drying and roasting furnace 11 so as to analyze and adjust the process parameters of continuous sedimentation reactor 48, filter device, and continuous drying and roasting furnace 11 in a timely manner to obtain radioactive powder products 13 of different types and specifications.

[0038] Specifically, a slurry sampling port 21 is provided on the continuous sedimentation reactor 4 or on the connecting pipeline between the continuous sedimentation reactor 4 and the filtration device 8; a filtrate sampling port 22 is provided on the filtration device; a filter cake sampling port 23 is provided on the filtration device 8 or on the connecting pipeline between the filtration device 8 and the continuous drying and roasting furnace 11; and an oxide powder product sampling port 24 is provided on the continuous drying and roasting furnace 11. An automatic sampling device 25 is connected to each of these sampling ports to obtain corresponding samples for analyzing the oxalate precipitate's crystal particle size distribution, conversion rate, filter cake moisture content, and the carbon and moisture content of the oxide powder product, among other physical properties. The sampling volume for the slurry is 2-30 mL, the filtrate is 2-30 mL, the filter cake is 2-20 g, and the oxide powder product is 2-20 g.

[0039] Unlike radioactive liquid sampling cabinets and manually operated robotic arms for sample collection, automatic sampling devices can automatically sample and transfer solid, liquid, or solid-liquid mixtures from multiple workstations using pre-set programs. This allows for the sampling of multiple types of highly radioactive samples from a single device, while avoiding radiation exposure to operators.

[0040] In some embodiments, the effective volume of the continuous sedimentation reactor 4 does not exceed 1L to ensure that critical safety is not affected during complex physicochemical changes that occur within the continuous sedimentation reactor.

[0041] In some embodiments, the system further includes a raw material receiving tank 3 and an oxalic acid storage tank 7. The raw material receiving tank 3 is connected to the continuous precipitation reactor 4 via a first quantitative conveying device 16 and integrated within the glove box 1. It is used to continuously and quantitatively supply nitrate solution as raw material to the continuous precipitation reactor 4 via the first quantitative conveying device 16. The oxalic acid storage tank 7 is connected to the continuous precipitation reactor 4 via a second quantitative conveying device 18. The oxalic acid storage tank 7 can be located outside the glove box 1, or, if the volume of the glove box is not considered, it can be located inside the glove box 1. It is used to continuously and quantitatively supply oxalic acid solution to the continuous precipitation reactor 4 via the second quantitative conveying device 18, allowing it to undergo the precipitation reaction with the nitrate solution provided by the raw material receiving tank 3. The precipitation reaction principle is as follows:

[0042] M(NO3)4+2H2C2O4+6H2O=M(C2O4)2·6H2O↓+4HNO3

[0043] Based on the reaction principle, by controlling the feeding rate of the two liquid streams, the oxalic acid is slightly in excess. The feeding rate of the nitrate liquid is controlled at 1~10L / h, and the feeding rate of the oxalic acid solution is controlled at 1~10L / h, so that the residual amount of oxalic acid in the precipitate slurry is maintained at 0.01~0.5mol / L, and the molar concentration of the oxalic acid solution is 0.1~1mol / L.

[0044] In some embodiments, both the raw material receiving tank 3 and the continuous sedimentation reactor 4 are externally encased in lead-boron polyethylene as a localized radiation protection shielding layer. This localized shielding design reduces the overall shielding layer thickness of the glove box, thereby lowering the installation site requirements for the glove box. Furthermore, it reduces the radiation impact on maintenance personnel from residual radioactive sources in other complex equipment during the inspection and maintenance of a particular device.

[0045] In some embodiments, the system further includes a self-suction device 2 for the feed liquid, which is connected to the raw material feed liquid receiving tank 3. The self-suction device 2 can be located outside the glove box 1; however, if the volume of the glove box is not a consideration, it can also be located inside the glove box 1. It is used to transport the nitrate feed liquid generated in the upstream process of the reprocessing plant to the raw material feed liquid receiving tank 3. Through the self-suction design, the quantitative and automatic transfer of radioactive feed liquid can be achieved, reducing the risk of radiation exposure for personnel.

[0046] In some embodiments, the system further includes a prefilled liquid storage tank 6, which is connected to the continuous sedimentation reactor 4 via a third quantitative conveying device 17. The feed liquid in the prefilled liquid storage tank 6 is transferred into the continuous sedimentation reactor 4 in one go to provide prefilled liquid to the continuous sedimentation reactor 4. The prefilled liquid is a mixture of 0.01~1 mol / L oxalic acid and 1~6 mol / L nitric acid solution, with a volume of 50~1000 mL. By transferring the prefilled liquid before the continuous sedimentation operation, the supersaturation during the crystallization of the precipitation reaction can be controlled, thereby making it easier to control the size and morphology of the crystals, which is beneficial for subsequent filtration and calcination operations.

[0047] In some embodiments, the system also includes a feed return device 5, which is connected to the continuous sedimentation reactor 4 and the filtration device 8, respectively, for raw material recovery and waste liquid treatment. By setting up the feed return device, the transfer of radioactive feed liquid and the removal of sources before maintenance can be carried out automatically using the feed return device, reducing the radiation risk to personnel.

[0048] In some embodiments, the continuous sedimentation reactor 4 has an overflow port on its side wall, and the overflow port is equipped with a three-way valve, which is connected to the filter device 8 and the feed return device 5 respectively. As the feed solution is continuously added into the continuous sedimentation reactor 4, the reacted oxalate precipitate slurry is continuously discharged from the overflow port on the side wall of the continuous sedimentation reactor 4. The flow direction of the precipitate slurry is controlled by the three-way valve, and the precipitate slurry is adjusted to enter the filter device 8 or the feed return device 5 for recovery according to the preparation rhythm. The residence time of the continuous sedimentation reaction is controlled by adjusting the flow rates of the nitrate feed solution and the oxalic acid solution.

[0049] In some embodiments, since the items flowing through the three-way valve are solid-liquid mixtures, there is a risk of clogging. Therefore, the three-way valve is preferably made of radiation-resistant material and is equipped with an automatic flushing and drying structure, so that the three-way valve can be unblocked without human intervention.

[0050] In some embodiments, the filtration device is an external filter surface rotary drum filter, which has five functional stations: filtration, washing, suction, backflushing discharge, and filter plate regeneration. It also contains at least five filter plates. During one rotation of the drum, each filter plate sequentially passes through the stations of filtration, washing, suction, backflushing discharge, and filter plate regeneration to complete the corresponding operations, thereby converting the oxalate precipitate slurry into oxalate filter cake. The oxalate filter cake is then discharged through backflushing into the continuous drying and calcining furnace 11. The distribution rhythm of the precipitate slurry in the filtration device 8 is adjusted by coordinating the three-way valve at the overflow port of the continuous sedimentation reactor 4 with the rotation speed of the filtration device's drum.

[0051] In some embodiments, the system further includes one or more of a vacuum device 14, a compressed air device 15, a washing liquid storage tank 9, and a regenerated liquid storage tank 10, wherein: the vacuum device 14 is connected to the filter device 8 and is used to provide the filter device 8 with the negative pressure required for the filtration and suction processes, the filtration negative pressure being -20kPa to -90kPa, and the suction negative pressure being -20kPa to -90kPa; the washing liquid storage tank 9 is connected to the filter device 8 via a fourth metering conveying device 19 and is used to provide the filter device 8 with the washing liquid required for the washing process, wherein during washing, the washing liquid in the washing liquid storage tank 9 is sprayed by the fourth metering conveying device 19. The washing liquid is a mixed solution of oxalic acid and nitric acid, sprayed onto the filter plate. The compressed air device 15 is connected to the filter device 8 and is used to provide the filter device 8 with the pulse pressure required for the backflushing and unloading process. The pressure is 0.1~1MPa. The regeneration liquid storage tank 10 is connected to the filter device 8 through the fifth quantitative conveying device 20 and is used to provide the filter device 8 with the regeneration liquid required for the filter plate regeneration process. When the filter plate is regenerated, the regeneration liquid in the regeneration liquid storage tank 10 is sprayed onto the filter plate by the fifth quantitative conveying device 20. The regeneration liquid is a mixed solution of 0~1mol / L oxalic acid and 3~13mol / L nitric acid solution, and the temperature of the regeneration liquid is 20~90℃.

[0052] In some embodiments, the system further includes a filtrate receiving tank 12, which is connected to the filtration device 8 and the feed return device 5 respectively. The filtrate, washing liquid and regenerated liquid generated by the filtration device 8 are first discharged into the filtrate receiving tank 12 for temporary storage and then enter the feed return device 5 for raw material recovery and waste liquid treatment.

[0053] In some embodiments, the containers such as the raw material liquid receiving tank 3, the filtrate receiving tank 12, the prefilled liquid storage tank 6, the oxalic acid storage tank 7, the washing liquid storage tank 9, and the regenerated liquid storage tank 10 are all geometrically sound devices to prevent critical risks.

[0054] In some implementations, this system is mainly designed for scenarios with small production throughput and small equipment size, and has a highly integrated structure. Based on safety and maintenance considerations, the first to fifth quantitative delivery devices can all use traditional radioactive liquid delivery methods (such as air lifting), or they can use civilian equipment with special requirements (such as metering pumps). The equipment is simpler, easier to operate, and has a lower cost.

[0055] In some embodiments, the glove box 1 of this system is equipped with a liquid handling area and a powder handling area, located at opposite ends of the glove box 1. The continuous sedimentation reactor 4 and the filter device 8 are located in the liquid handling area, while the continuous drying and calcining furnace 11 and the automatic sampling device 25 are located in the powder handling area. By rationally arranging the liquid handling area and the powder handling area within the glove box, the two types of materials can be prevented from interfering with each other. Furthermore, both the liquid handling area and the powder handling area are equipped with a slope gradient. Specifically, a slope gradient combined with a threaded guide channel is used, with a spiral pattern designed on the bottom surface. This forces leaked liquid under abnormal operating conditions to be channeled to the glove box floor drain for sealed collection, preventing leaked liquid from flowing into the powder handling area under abnormal operating conditions.

[0056] In some embodiments, the glove box 1 is equipped with an exhaust duct with multiple branches. The outlets of each branch are located near the continuous sedimentation reactor 4, the filter device 8, the continuous drying and roasting furnace 11, and the raw material liquid receiving tank 3, respectively. It is also equipped with a flow regulation mechanism. By regulating the flow rate on different branches, the air flow direction can be adjusted, which can reduce the dispersion of leaked aerosols in the entire glove box under abnormal operating conditions.

[0057] In some embodiments, the continuous drying and calcining furnace 11 has a drying zone and a calcining zone, which are connected by an insulating sleeve. The oxalate filter cake is conveyed by a screw conveyor and sequentially passes through the drying zone and the calcining zone for drying and calcination. The residence time of the oxalate filter cake in the drying zone and the calcining zone is controlled by controlling the screw speed, wherein the residence time in the drying zone is 2-60 minutes and the residence time in the calcining zone is 10-120 minutes.

[0058] In some embodiments, the continuous drying and roasting furnace 11 is also connected to a compressed air device 15, which provides the air required for the roasting process at a pressure of 0.02 to 0.5 MPa.

[0059] The preparation process of the low-throughput radioactive powder product preparation system in this embodiment is described in detail below:

[0060] The nitrate solution is transported into the raw material receiving tank 3 using the self-pumping device 2. The prefilled liquid in the prefilled liquid storage tank 6 is transported to the continuous sedimentation reactor 4 through the third quantitative conveying device 17, and the magnetic stirring of the continuous sedimentation reactor is turned on.

[0061] Using the first quantitative conveying device 16 and the second quantitative conveying device 18, nitrate solution and oxalic acid solution are continuously and quantitatively added to the continuous sedimentation reactor 4 from the raw material receiving tank 3 and the oxalic acid storage tank 7, respectively. The resulting oxalate precipitate slurry flows into the material return device 5 or into the filter device 8 through the three-way valve of the overflow port on the side wall of the continuous sedimentation reactor, according to the operating rhythm of the filter device 8.

[0062] The slurry flowing into the filtration device 8 is transformed into a filter cake through a series of operations including filtration, washing, suction, backflushing, and filter plate regeneration. Specifically: the vacuum device 14 provides vacuum power to the filtration device 8 for filtration and suction; the fourth quantitative conveying device 19 sprays the washing liquid in the washing liquid storage tank 9 onto the surface of the filter plate of the filtration device 8 for filter cake washing; the compressed air device 15 provides compressed air power to the filtration device 8 for backflushing and unloading; and the fifth quantitative conveying device 20 sprays the regenerated liquid in the regenerated liquid storage tank 10 onto the surface of the filter plate of the filtration device 8 for filter plate regeneration.

[0063] The filter cake produced by the filtration device 8 enters the continuous drying and calcining furnace 11 for drying and calcining to obtain oxide powder product 13. The air required during the drying and calcining process is provided by the compressed air device 15.

[0064] The filtrate, washing liquid, and regenerated liquid generated by the filtration device 8 are first temporarily stored in the filtrate receiving tank 12, and then transported to the material return device 5 for raw material recovery and waste liquid treatment.

[0065] During the process, an automatic sampling device 25 is used to take samples from the precipitate slurry sampling port 21, the filtrate sampling port 22, the filter cake sampling port 23, and the oxide powder product sampling port 24, respectively. The analysis yields physical property parameters such as the crystal particle size distribution, conversion rate, moisture content of the filter cake, and carbon and moisture content of the oxide powder product. The process parameters are adjusted according to the type and specifications of the radioactive powder product to be obtained until the desired type and specifications of radioactive powder product are obtained.

[0066] During the thermal verification test, the automatic sampling device 25 was used to take samples at the precipitate slurry sampling port 21, the filtrate sampling port 22, the filter cake sampling port 23, and the oxide powder product sampling port 24, respectively. The analysis yielded the continuous preparation process flow and key process operation range parameters of the radioactive powder product in the post-processing plant, which can be used as a reference for similar working conditions.

[0067] The low-throughput radioactive powder product preparation system of this embodiment integrates the continuous precipitation reactor, filtration device, continuous drying and calcining furnace, and automatic sampling device all within a glove box, resulting in a highly integrated structure. It features low throughput, small scale, low cost, easy maintenance, and easy adjustment of process operating parameters. It can prepare various types and specifications of radioactive powder products, and the process is simple, safe, reliable, and highly operable. Furthermore, it can conduct radioactive experimental studies such as process parameter verification, providing a continuous process flow and key process operating range parameters for radioactive powder product preparation in reprocessing plants, and offering reference for similar operating conditions. This guides parameter control in industrial-scale systems, ensuring the smooth production of radioactive powder products.

[0068] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A low-throughput radioactive powder product preparation system, characterized in that, It includes a glove box, a continuous sedimentation reactor, a filtration device, a continuous drying and roasting furnace, and an automatic sampling device, wherein the continuous sedimentation reactor, the filtration device, the continuous drying and roasting furnace, and the automatic sampling device are all integrated into the glove box; The continuous precipitation reactor is used to receive the raw material liquid and carry it to a precipitation reaction to generate oxalate precipitate. The filtration device is connected to the continuous sedimentation reactor and is used to filter the liquid after the sedimentation reaction to separate the oxalate filter cake. The continuous drying and roasting furnace is connected to the filtration device and is used to dry and roast the separated oxalate filter cake to obtain a radioactive powder product. The automatic sampling device is connected to the continuous sedimentation reactor, the filtration device, and the continuous drying and calcining furnace, respectively, and is used to sample the materials processed by the continuous sedimentation reactor, the filtration device, and the continuous drying and calcining furnace, so as to analyze and adjust the process parameters of the continuous sedimentation reactor, the filtration device, and the continuous drying and calcining furnace in a timely manner to obtain radioactive powder products of different types and specifications.

2. The low-throughput radioactive powder product preparation system according to claim 1, characterized in that, It also includes a raw material liquid receiving tank and an oxalic acid storage tank. The raw material receiving tank is connected to the continuous sedimentation reactor and integrated into the glove box, and is used to provide nitrate solution as raw material to the continuous sedimentation reactor. The oxalic acid storage tank is connected to the continuous precipitation reactor and is used to supply oxalic acid solution to the continuous precipitation reactor so that it can undergo the precipitation reaction with the nitrate solution provided by the raw material receiving tank.

3. The low-throughput radioactive powder product preparation system according to claim 2, characterized in that, Both the raw material receiving tank and the continuous sedimentation reactor are covered with a local radiation protection shielding layer.

4. The low-throughput radioactive powder product preparation system according to claim 2, characterized in that, It also includes a liquid self-pumping device. The self-suction device for the feed liquid is connected to the raw material feed liquid receiving tank and is used to transport the nitrate feed liquid generated in the upstream process of the post-treatment plant to the raw material feed liquid receiving tank.

5. The low-throughput radioactive powder product preparation system according to claim 4, characterized in that, It also includes a prefilled liquid storage tank. The prefilled liquid storage tank is connected to the continuous sedimentation reactor and is used to provide prefilled liquid to the continuous sedimentation reactor. The prefilled liquid is a mixture of 0.01~1 mol / L oxalic acid and 1~6 mol / L nitric acid solution.

6. The low-throughput radioactive powder product preparation system according to claim 5, characterized in that, It also includes a liquid return device. The feed return device is connected to the continuous sedimentation reactor and the filtration device, respectively, and is used for raw material recovery and waste liquid treatment.

7. The low-throughput radioactive powder product preparation system according to claim 6, characterized in that, The filtration device is an external filter hub-type filter, which has five functional stations inside: filtration, washing, suction, backflushing and unloading, and filter plate regeneration, and has no less than five filter plates inside.

8. The low-throughput radioactive powder product preparation system according to claim 7, characterized in that, It also includes one or more of a vacuum device, a compressed air device, a washing liquid storage tank, and a regenerated liquid storage tank; The vacuum device is connected to the filter device and is used to provide the negative pressure required for the filtration and suction processes of the filter device. The washing liquid storage tank is connected to the filtration device and is used to provide the filtration device with the washing liquid required for the washing process. The compressed air device is connected to the filter device and is used to provide the filter device with the pulse pressure required for the backflushing and unloading process; The regenerated liquid storage tank is connected to the filtration device and is used to provide the filtration device with the regenerated liquid required for the filter plate regeneration process.

9. The low-throughput radioactive powder product preparation system according to any one of claims 1 to 8, characterized in that, The glove box is equipped with a liquid handling area and a powder handling area. The liquid feed operation area and the powder operation area are located at opposite ends of the glove box. The continuous sedimentation reactor and the filtration device are located in the liquid feed operation area, and the continuous drying and calcining furnace and the automatic sampling device are located in the powder operation area. The liquid feed operation area and the powder operation area are provided with a slope gradient.

10. The low-throughput radioactive powder product preparation system according to claim 9, characterized in that, The glove box is equipped with an exhaust duct. The exhaust duct has multiple branch pipes, and the outlets of each branch pipe are respectively located near the continuous sedimentation reactor, the filtration device, the continuous drying and roasting furnace and the raw material liquid receiving tank, and are equipped with a flow regulation mechanism.

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