Filter box and protection device for advanced fast reactor special alpha nuclide human body protection

Abstract

The invention belongs to the technical field of nuclear radiation protection, and particularly relates to an advanced fast reactor special alpha nuclide human body protection filter box and a protection device. A tank cover is connected with the upper end of a tank body, a rubber pad is arranged in the tank cover, the tank cover and the tank body are externally connected through a connecting rope, a special alpha nuclide filtering unit is arranged in the tank body, air particle filtering paper is arranged below the special alpha nuclide filtering unit, and a rubber plug is additionally arranged on the inner side of the tank cover; sealant is poured into the seam of the special alpha nuclide filter unit and the air particle filter paper. The filtering efficiency of special alpha nuclide aerosol is larger than 99.99% through the gradient filtering design, the breathing resistance is reduced to 180 Pa or below by adopting high-specific-surface-area impregnated carbon (larger than 1000 m < 2 > / g), and the filtering efficiency and the performance stability of the filtering box are enhanced in the mode that the air particle filtering paper and the impregnated carbon are stacked.

Description

Technical Field

[0001] This invention belongs to the field of nuclear radiation protection technology, specifically relating to a filter box and protective device for human protection against special alpha nuclides in advanced fast reactors. Background Technology

[0002] During the operation of the fourth-generation advanced fast reactor, bismuth (Bi-209) in the coolant undergoes a neutron activation reaction to produce polonium (a special alpha nuclide). This special alpha nuclide is an extremely toxic alpha radioactive nuclide, and its aerosol poses a very high risk to humans (half-life 138 days, specific activity > 5 × 10³ TBq / g). Currently, protective technologies against this special alpha nuclide are mainly divided into two categories: environmental remediation and human protection. In the field of environmental remediation, existing technologies mostly use rare-earth filter membranes to reduce the concentration of radioactivity in space. While the rare-earth filter membrane proposed in patent CN206541633U can reduce the concentration of special alpha nuclides in the coolant, its structural design is geared towards industrial systems and cannot meet the lightweight requirements of human protective equipment. In the field of human protection, traditional high-efficiency particulate air (HEPA) filter media has a filtration efficiency of only 99.5% for 0.3μm particles (referencing GB / T 6165-2021), and has not been optimized for the nanoscale particle size (0.1~0.6μm) and radiochemical characteristics of special α-nucleoside aerosols.

[0003] Existing personal protective equipment has the following three problems: 1) Poor adaptability to protective scenarios, failing to consider the working conditions of special alpha nuclides, which may lead to a sharp drop in filtration efficiency (referencing the "Technical Specification for Aerosol Protection of Nuclear Facilities"); 2) Insufficient gas-solid separation, existing filter boxes do not distinguish between gaseous and solid special alpha nuclides capture mechanisms. For example, although CN119517478A uses an air supply system to reduce breathing resistance, it does not integrate a gradient filtration design, resulting in low adsorption efficiency for gaseous special alpha nuclides; 3) Insufficient material durability, traditional impregnated carbon is easily deactivated in high temperature and high humidity environments (specific surface area decay > 30%), and it does not load precious metals, rare earth and other metal catalytic components, making it impossible to achieve chemical stabilization of special alpha nuclides. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a filter cartridge and protective device for human protection against special alpha nuclides in advanced fast reactors. The filter cartridge achieves a filtration efficiency of >99.99% for special alpha nuclide aerosols through a gradient filtration design, and uses high specific surface area impregnated carbon (>1000m²). 2 / g) Reduce breathing resistance to below 180Pa, and enhance filtration efficiency and filter box performance stability by stacking air particle filter paper and impregnated carbon; the protective device matched with the filter box has a reasonable structural design, is easy to use and replace, has strong sealing performance, and is suitable for personnel safety protection in low-concentration special alpha nuclide scenarios.

[0005] The technical solution adopted in this invention is as follows:

[0006] A filter cartridge for an advanced fast reactor personal protective equipment includes a canister lid, a rubber gasket, a connecting rope, a special alpha nuclide filter unit, air particle filter paper, sealant, and a rubber stopper. The canister lid is connected to the upper end of the canister body, and a rubber gasket is provided inside the canister lid. The canister lid and the canister body are externally connected by a connecting rope. A special alpha nuclide filter unit is provided inside the canister body, and air particle filter paper is provided below the special alpha nuclide filter unit. A rubber stopper is installed on the inner side of the canister lid. Sealant is filled at the joint between the special alpha nuclide filter unit and the air particle filter paper. The canister lid, rubber gasket, connecting rope, sealant, and rubber stopper serve as structural components and provide sealing.

[0007] The special α-nucleoside filtration unit adopts a cylindrical, axially inlet layered structure, consisting of three layers of impregnated carbon and two layers of air particle filter paper stacked in sequence.

[0008] The can lid is made of 6061-T6 aluminum alloy or other hard aluminum plate material, with an embedded rubber gasket containing 50% to 80% fluorine and a compression set rate of ≤8%.

[0009] After the special α-nucleoside filter unit and the air particle filter paper are filled with sealant and cured, the Shore A hardness is not less than 40, and it maintains elasticity from -54℃ to 232℃.

[0010] The air particle filter paper consists of three layers of gradient filter paper and a gas separator. The top layer is made of polypropylene meltblown material with a fiber diameter of 5.2±0.3μm and a basis weight of 28-34g / m2. The middle layer is a glass fiber / polytetrafluoroethylene composite membrane with an average pore size of 0.50-0.54μm and a porosity of 80%-86%. The bottom layer is a polyvinylidene fluoride nano-cobweb membrane with a fiber diameter of 98±12nm and electrostatic electret treatment.

[0011] The air inlet of the particulate filter paper is equipped with a distribution plate for uniform airflow. This plate is made of TC4 titanium alloy with a surface plasma nitriding hardness of HV0.3 ≥ 450. Its spiral fin height is 2.00 ± 0.05 mm, and the optimized tilt angle is 17.8°.

[0012] The impregnated carbon achieves specific adsorption and retention of specific α nuclides in the gas. The substrate is commercial activated carbon, and the impregnating agent is a metal nitrate of palladium, silver, praseodymium, or cerium, with an impregnating agent content of 20 g / L to 100 g / L. The specific surface area of ​​the impregnated carbon after impregnation is ≥1000 m2 / g, which enables it to have specific adsorption capacity for Po.

[0013] The preparation process of impregnated charcoal is as follows:

[0014] The activated carbon was washed multiple times with tap water, deionized water, and ethanol, and then dried in an oven at 90℃~150℃ for 72 hours before use.

[0015] Take 5-20 grams of the above activated carbon and place it in a solution of palladium, silver, praseodymium, and cerium metal nitrates. Slowly add ascorbic acid and stir continuously for 24 hours. After draining, wash with ethanol and place in an oven to dry at 100℃-180℃ for 24 hours.

[0016] After drying, the activated carbon is placed in a tube furnace and calcined at 250℃~400℃ for 1~4 hours in an argon atmosphere for later use.

[0017] A protective device for human protection against special alpha nuclides in advanced fast reactors includes a mask, a canister connector, a water-blocking shield, a lens, a filter cartridge, and a headband. The mask adopts a linear single-sided folded edge according to ergonomics. A lens is provided at the eye position of the mask, and the water-blocking shield is located inside the mask. The canister connector is located on both sides of the mask. The canister connector is an integral planar structure, which facilitates matching and connection with the filter cartridge. During assembly, it is embedded inside the mask to shorten the gap and improve the dynamic airtightness after the mask is worn. A headband is connected to the rear of the mask, and the headband adopts a five-point structure.

[0018] The cover is made of polyetherimide modified material. The outer side of the cover is provided with a modular interface. Two inhalation valves and one exhalation valve are provided above and below the water-blocking cover. The inner layer of the water-blocking cover has a radial groove structure.

[0019] A method for using a special alpha nuclide protection device for an advanced fast reactor includes the following steps:

[0020] The special alpha nuclide filter unit is filled with 200 to 700 grams of impregnated carbon, and the impregnated carbon, air particle filter paper, impregnated carbon, air particle filter paper, and impregnated carbon are stacked in sequence; all air particle filter unit components are assembled by laser welding, and the annular sealing groove is filled with sealant.

[0021] Align the special alpha nuclide filter unit with the air particulate filter unit through a laser welding interface, and then tighten the can lid to the 45°-60° locking position.

[0022] Helium gas is injected into the inlet, and the concentration at the outlet is monitored by a mass spectrometer.

[0023] Embed the edge of the water-blocking cover into the cover's slot;

[0024] Align the can connector seat with the mounting port on the cover and connect it;

[0025] Place the lens into the frame and secure it to the frame using a clip or buckle;

[0026] Align the headband connector with the headband mounting hole on the cover;

[0027] Align the filter box interface with the tank connector seat. The connection method is usually threaded connection or quick plug-in.

[0028] The beneficial effects of this invention are as follows:

[0029] (1) The present invention provides a filter box for human protection against special α nuclides in an advanced fast reactor. It uses activated carbon impregnated with precious metals, rare earth metals and other materials as the key filter material, which can achieve high-efficiency filtration of special α nuclides in the gas space, with a filtration efficiency of 99.99%.

[0030] (2) The filter box for human protection of special alpha nuclides in advanced fast reactors provided by the present invention, through optimized structural design, adopts a three-layer stacked filter paper and impregnated carbon structure, which can effectively intercept gas space particles and other impurities, and can extend the service life of the special alpha nuclide filter box.

[0031] (3) The present invention provides an advanced fast reactor special alpha nuclide protection device that ensures the face is isolated from the outside world while allowing personnel to breathe freely. It can also be connected to the filter box provided by the present invention to achieve the protection function against special alpha nuclides and effectively reduce the risk of internal irradiation of special alpha nuclides.

[0032] (4) The present invention provides a method for using an advanced fast reactor special α nuclide protection device, which is suitable for the safety protection of operators in low-concentration special α nuclide scenarios. Attached Figure Description

[0033] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in describing the embodiments of the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments recorded in the present invention. Those skilled in the art can derive other drawings from the following drawings without any creative effort.

[0034] Figure 1 A schematic diagram of a filter box structure for human protection against special alpha nuclides in an advanced fast reactor, provided by the present invention;

[0035] Figure 2 This is a schematic diagram of the special α-nucleoside filtration unit structure in the filter cartridge;

[0036] Figure 3 This invention provides a schematic diagram of a protective device for human protection against special alpha nuclides in an advanced fast reactor.

[0037] In the diagram: 1-can lid, 2-rubber gasket, 3-connecting rope, 4-special alpha nuclide filter unit, 5-air particle filter paper, 6-sealing paste, 7-rubber stopper, 8-impregnated carbon, 9-cover, 10-can connector seat, 11-water barrier, 12-lens, 13-filter box, 14-headband. Detailed Implementation

[0038] The technical solutions of the embodiments 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, and 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.

[0039] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., refer to the orientation or positional relationship shown in the accompanying drawings, and are used only for the convenience of describing the invention and simplifying 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, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0040] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" 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 mechanical connection or an electrical connection; they can refer to a direct connection or a connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] like Figure 1 As shown, the present invention provides a filter box for an advanced fast reactor personal protective equipment, comprising a canister lid 1, a rubber gasket 2, a connecting rope 3, a special alpha nuclide filtration unit 4, air particle filter paper 5, sealant 6, and a rubber stopper 7. The canister lid 1 is connected to the upper end of the canister body, and the rubber gasket 2 is provided inside the canister lid 1. The canister lid 1 and the canister body are connected externally by the connecting rope 3. The special alpha nuclide filtration unit 4 is provided inside the canister body, such as... Figure 2 As shown, the special α-nucleoside filter unit 4 adopts a cylindrical, axially air-inlet layered structure, consisting of three layers of impregnated carbon 8 and two layers of air particle filter paper 5 stacked sequentially; the air particle filter paper 5 is located below the special α-nucleoside filter unit 4, and a rubber stopper 7 is installed inside the canister lid 1; the joint between the special α-nucleoside filter unit 4 and the air particle filter paper 5 is filled with sealant 6; the canister lid 1, rubber gasket 2, connecting rope 3, sealant 6, and rubber stopper 7 serve as structural components and provide sealing.

[0042] The can lid 1 is made of 6061-T6 aluminum alloy or other hard aluminum plate material, and the fluorine content of the embedded rubber gasket 2 is 50% to 80%, with a compression set rate of ≤8%.

[0043] The special α-nucleoside filter unit 4 and the air particle filter paper 5 are filled with sealant 6. After curing, the Shore A hardness is not less than 40, and it maintains elasticity from -54℃ to 232℃.

[0044] The special α-nucleoside filter unit 4 has an inner diameter of 55mm-65mm, a wall thickness of 1.50±0.02mm, and an anodized film thickness of 20.0±0.5μm.

[0045] The inner side of the can lid 1 is fitted with a rubber stopper 7, which can withstand γ-radiation doses up to 100kGy and acid and alkali corrosion within the pH range of 0-14.

[0046] The air particle filter paper 5 is made of high-efficiency, low-resistance filter material and adopts a gradient fiber structure design with micro-nano structure to achieve the interception and capture of special α-nucleoside aerosols.

[0047] The air particle filter paper 5 consists of three layers of gradient filter paper and a gas separator. The surface layer is made of polypropylene meltblown material with a fiber diameter of 5.2±0.3μm and a basis weight of 28-34g / m². 2 The middle layer is a glass fiber / PTFE composite membrane with an average pore size of 0.50-0.54 μm and a porosity of 80%-86%. The bottom layer is a PTFE nano-spiderweb membrane with a fiber diameter of 98±12 nm and electrostatic electret treatment. The air particle filter paper has five air inlets, located on the outer side of the surface filter paper. It also features air distribution plates for uniform airflow, made of TC4 titanium alloy with a surface plasma nitriding hardness of HV0.3≥450. The spiral fin height is 2.00±0.05 mm, and the optimized tilt angle is 17.8°.

[0048] The height of the air particulate filter paper 5 is determined to be 5-20 mm based on the structure of the filter box 13 and the distribution of flow rate, specific velocity and resistance.

[0049] The impregnated carbon 8 in the special α-nucleus filtration unit 4 is a specially impregnated activated carbon, which can achieve specific adsorption and retention of special α-nuclei in the gas. The substrate is commercial activated carbon, and further impregnating agents of metal nitrates such as palladium, silver, praseodymium, and cerium are used. The impregnating agent content is 20g / L to 100g / L, and the specific surface area of ​​the impregnated carbon 8 after impregnation is ≥1000m². 2 / g, which gives it the specific adsorption capacity for Po.

[0050] like Figure 3As shown, this invention provides a protective device for human protection against special alpha nuclides in advanced fast reactors, comprising a mask body 9, a canister connector 10, a water-blocking cover 11, a lens 12, a filter cartridge 13, and a headband 14. The mask body 9 is designed based on ergonomics and mature domestic mask structures, employing a linear single-sided folded edge to ensure high sealing and comfortable wear. Lenses 12 are located at the eye positions on the mask body 9, and the water-blocking cover 11 is located inside the mask body 9. The canister connector 10 is located on both sides of the mask body 9 and is an integral planar structure, facilitating matching and connection with the filter cartridge 13. During assembly, it is embedded inside the mask body 9, shortening the gap and improving the dynamic airtightness after wearing the mask. The headband 14 is connected to the rear of the mask body 9. The headband 14 adopts a five-point structure, ensuring even force distribution on the head, with soft and comfortable edges for easy wear and ensuring a close fit between the mask body and the face.

[0051] The special alpha nuclide filtration units 4, through stacking, increase turbulence and ensure that the special alpha nuclide gas passes through the impregnated carbon 8 at a uniform concentration. Furthermore, according to experimental results, the filter paper provides a good initial interception effect for the special alpha nuclide. This design enhances the filtration efficiency and performance stability of the filter cartridge 13.

[0052] The height of the single-layer impregnated carbon 8 is 10mm-30mm, and the particle size distribution is D10=0.48mm, D50=0.85mm, D90=1.32mm;

[0053] Furthermore, the impregnated charcoal preparation process is implemented in three steps:

[0054] 1. Pretreatment: The activated carbon is washed multiple times with tap water, deionized water and ethanol, and then dried in an oven at 90℃~150℃ for 72h for later use.

[0055] 2. Impregnation treatment: Take 5-20 grams of the above activated carbon and place it in a solution of metal nitrates such as palladium, silver, praseodymium, and cerium. Slowly add ascorbic acid and stir continuously for 24 hours. After draining, wash with ethanol and place in an oven to dry at 100℃-180℃ for 24 hours.

[0056] 3. Calcination treatment: After drying, the activated carbon is placed in a tube furnace and calcined at 250℃~400℃ for 1~4 hours in an argon atmosphere for later use.

[0057] The cover 9 is made of polyetherimide modified material and has a temperature tolerance range of -30℃ to 120℃.

[0058] The outer side of the cover 9 is equipped with a modular interface, which supports quick replacement of spare filter boxes, etc., with a replacement time of ≤5 seconds.

[0059] The water-blocking cover 11 is provided with two air intake valves and one air exhalation valve at the top and bottom, which can allow the cold air entering the mask to effectively flush the lens, prevent the lens from fogging, and effectively avoid the problem of lens fogging during long-term use or in high humidity environments.

[0060] The inner layer of the water-blocking cover 11 has a radial groove structure with a groove depth of 0.5mm to 1.2mm, which is used to guide the condensate to the bottom water collection cavity.

[0061] The present invention provides a method for using a special alpha nuclide protection device for an advanced fast reactor, comprising the following steps:

[0062] The special alpha nuclide filter unit 4 is filled with 200-700 grams of impregnated carbon 8. Impregnated carbon 8, air particle filter paper 5, impregnated carbon 8, air particle filter paper 5, and impregnated carbon 8 are stacked sequentially and secured with a pre-tightening force of 0.4-0.6 MPa. All air particle filter unit 5 components are assembled by laser welding. The annular sealing groove is filled with sealant 6, with an injection volume of 50-200 grams. After curing at room temperature for 110 minutes, an elastic sealing layer is formed.

[0063] Align the special alpha nuclide filter unit 4 with the air particulate filter unit 5 using a laser welding interface, and apply 35-60N axial pressure until the mechanical lock makes a "click" sound. Then tighten the can lid 1 to the 45°-60° locking position, at which point the fluororubber gasket 2 will be compressed to ≥25%.

[0064] Helium gas at a pressure of 2.0 ± 0.05 kPa was injected into the inlet, and the concentration at the outlet was monitored using a mass spectrometer. The leakage rate was ≤ 5E-7 Pa·m. 3 / s, when the corresponding gap is ≤1.8μm, it is judged as qualified and constitutes filter box 13.

[0065] Insert the edge of the water-blocking cover 11 into the slot of the cover body 9, ensuring a tight fit. During the insertion process, the edge of the water-blocking cover 11 can be pressed appropriately to ensure it is fully engaged with the slot, preventing loosening or gaps and guaranteeing the water-blocking effect.

[0066] Align the can connector seat 10 with the mounting port on the cover 9. A threaded connection or quick-connect method is typically used. For a threaded connection, slowly screw the can connector seat 10 into the mounting port, rotating clockwise until tightened, ensuring a tight connection without leakage. For a quick-connect connection, insert the can connector seat 10 into the mounting port; a "click" sound indicates proper connection. You can then gently shake the can to check the stability of the connection.

[0067] Confirm the orientation of the lens 12, place the lens 12 into the frame, ensuring that the edge of the lens 12 is in full contact with the sealing strip, and then use a pressure strip or clips to fix the lens 12 to the frame.

[0068] Align the connecting end of the headband 14 with the headband mounting hole on the cover 9. A plug-in or hook-type connection is generally used. If it is a plug-in connection, insert the connecting end of the headband 14 into the mounting hole, and then adjust the length of the headband 14 using the adjusting buckle to fit the user's head size. If it is a hook-type connection, hook the hook on the headband 14 into the corresponding position of the mounting hole, and similarly adjust the tightness of the headband 14 using the adjusting buckle to ensure wearing comfort and stability.

[0069] Align the interface of filter box 13 with the tank connector seat. The connection method is usually threaded connection or quick-connect. If it is a threaded connection, slowly screw filter box 13 into tank connector seat 10. During the tightening process, keep filter box 13 vertical to ensure good sealing. If it is a quick-connect connection, insert filter box 13 into tank connector seat 10 until you hear a clear locking sound. At this time, check whether filter box 13 is installed firmly and without any looseness.

[0070] After securing all the components, the user should first adjust the headband 14 to its maximum length to easily put the protective mask on their head.

[0071] Gently lift the protective mask so that the lens 12 faces forward, then put the head strap 14 on from the back of your head and slowly pull down the protective mask to cover your face, ensuring that the edges of the mask fit snugly against your face, especially the bridge of your nose, cheeks and chin.

[0072] By adjusting the buckle on the headband 14, gradually tighten the headband to achieve a comfortable fit while ensuring a good seal for the protective mask. During adjustment, you can turn your head left and right slightly to check for any looseness or leaks in the protective mask.

[0073] After donning the protective mask, perform a deep breathing test to check its seal. If you feel air leaking in from the edges of the mask, you can further fine-tune the tightness of the headband 14 or readjust the position of the protective mask until a good seal is achieved.

[0074] By following the steps of securing and wearing the components described above, users can use this protective device correctly and safely, thereby reducing the risk of inhaling special alpha nuclide aerosols and ensuring user safety.

[0075] When the core filter material in the filter box 13 is saturated and the breathing resistance is >300Pa, press the filter boxes 13 on both sides of the mask firmly in sequence, rotate them and remove them. After removing one side of the filter box 13, a rubber gasket will pop into the working position at the connection to achieve a seal. When replacing the filter box 13, the rubber gasket will retract and the mask interface will remain connected to the filter box 13 to prevent outside air from entering the mask during replacement.

[0076] Example 1: Filter Material Preparation

[0077] The activated carbon was washed three times each with tap water, deionized water, and ethanol, and then dried in an oven at 100°C for 24 hours. It was then stored in a dry place for later use. 5g of the activated carbon was placed in 30mL of silver nitrate solution, and ascorbic acid was slowly added to initiate a reduction reaction. The mixture was stirred at 300rpm for 12 hours. After draining, it was washed once with ethanol and then dried in an oven at 100°C for 24 hours. After drying, the activated carbon was calcined in a tube furnace at 300°C under an argon atmosphere for 2 hours.

[0078] Example 2: Filter Cartridge Assembly

[0079] The special alpha nuclide filter unit 4 is filled with 385 grams of impregnated carbon, and impregnated carbon 8, air particle filter paper 5, impregnated carbon 8, air particle filter paper 5, and impregnated carbon 8 are stacked in sequence and locked with a pre-tightening force of 0.5 MPa. All air particle filter unit 5 components are assembled by laser welding, and the annular sealing groove is filled with 60 grams of sealant 6. After curing at room temperature for 110 minutes, an elastic sealing layer is formed.

[0080] Align the special alpha nuclide filter unit 4 with the air particulate filter unit 5 using a laser welding interface, and apply 35-60N axial pressure until the mechanical lock makes a "click" sound. Then tighten the can lid 1 to the 55° locking position, at which point the fluororubber gasket 2 is compressed to 32%.

[0081] Helium gas at a pressure of 2.0 ± 0.05 kPa was injected into the inlet, and its concentration at the outlet was monitored using a mass spectrometer. The leakage rate was 3.5E-7 Pa·m. 3 / s, corresponding to a gap of 1.2μm; ≤5E-7Pa·m 3 / s, corresponding to a gap ≤1.8μm, is considered qualified, and the filter box assembly is complete.

[0082] Example 3: Filter Cartridge Performance Test

[0083] Ventilation resistance characteristic test: The ventilation resistance characteristics of the filter box were tested in accordance with GB 2890-2022. When the air volume was 30L / min, the ventilation resistance of the filter box was 170Pa, which met the relevant ventilation resistance limit of the filter element specified in the standard.

[0084] Air tightness test: The prototype was clamped using a special fixture, and the air switch was turned on to ensure that the air pressure entering the filter box was maintained at 15±2 kPa. The fixture holding the prototype was immersed in a water tank for 1 minute, and the filter was rotated and tilted. The water tank light was turned on, and no bubbles were observed escaping from the surface of the prototype within 1 minute, indicating that the air tightness of the special alpha nuclide protective mask prototype met the requirements of GB2890-2022 standard.

[0085] Special alpha nuclide filtration performance test: The filter cartridge was connected to a self-developed special alpha nuclide volatilization device. The irradiated sample was heated, and the special alpha nuclide was passed through the filter cartridge with the carrier gas. The carrier gas flow rate was controlled at 30 L / min. The gas before and after entering the filter cartridge was washed with a strong acid solution. After the test, the test gas circuit was disassembled and the washing bottle was transferred. The radioactivity activity was measured using an alpha spectrometer. The final activity concentrations of the special alpha nuclide in the washing bottles before and after the filter cartridge were 32583 cpm and 3 cpm, respectively. Further calculation showed that the filtration efficiency of the special alpha nuclide in the filter cartridge was 99.99%.

[0086] Example 4: Preparation and Wearing Before Use

[0087] After inserting the edge of the water-blocking cover 11 into the slot of the cover body 9, fix the can connector seat 10, lens 12, headband 14, and filter box 13 onto the cover body 9 in sequence. After fixing all the above components, the user first adjusts the headband 14 to its maximum length so that the protective mask can be easily put on the head.

[0088] Gently lift the face shield, ensuring the lens 12 faces forward. Then, slip the headband 14 over your head from behind and slowly pull the face shield down to cover your face, ensuring the edges fit snugly against your face, especially around the bridge of your nose, cheeks, and chin. Gradually tighten the headband by adjusting the buckles on the headband 14 to achieve a comfortable fit that also ensures a good seal. After donning the face shield, perform a deep breathing test to check its seal.

[0089] By following the steps of securing and wearing the components described above, users can use this protective device correctly and safely, thereby reducing the risk of inhaling special alpha nuclide aerosols and ensuring user safety.

[0090] While those skilled in the art will recognize that the present invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention, the embodiments should be considered illustrative and non-limiting in all respects. The scope of the invention is defined by the appended claims rather than the foregoing description, and therefore all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0091] Furthermore, it should be understood that although the present invention is described according to embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A filter box for advanced fast reactor personal protective equipment, characterized in that, The container includes a can lid (1), a rubber pad (2), a connecting rope (3), a special alpha nuclide filter unit (4), an air particle filter paper (5), a sealant (6), and a rubber stopper (7). The can lid (1) is connected to the upper end of the container body. The can lid (1) has a rubber pad (2) inside. The can lid (1) is connected to the container body externally by a connecting rope (3). The container body has a special alpha nuclide filter unit (4) inside. An air particle filter paper (5) is located below the special alpha nuclide filter unit (4). A rubber stopper (7) is installed on the inside of the can lid (1). The joint between the special alpha nuclide filter unit (4) and the air particle filter paper (5) is filled with sealant (6). The can lid (1), rubber pad (2), connecting rope (3), sealant (6), and rubber stopper (7) serve as structural components and provide sealing.

2. The filter cartridge of the advanced fast reactor personal protective equipment according to claim 1, characterized in that, The special α-nucleoside filtration unit (4) adopts a cylindrical, axially inlet layered structure, consisting of three layers of impregnated carbon (8) and two layers of air particle filter paper (5) stacked in sequence.

3. The filter cartridge of the advanced fast reactor personal protective equipment according to claim 1, characterized in that, The can lid (1) is made of 6061-T6 aluminum alloy or other hard aluminum plate material, with an embedded rubber gasket (2) containing 50% to 80% fluorine and a compression set of ≤8%.

4. The filter cartridge of the advanced fast reactor personal protective equipment according to claim 1, characterized in that, The special α-nucleoside filter unit (4) and the air particle filter paper (5) are filled with sealant (6) and cured. The Shore A hardness is not less than 40 and it maintains elasticity from -54℃ to 232℃.

5. The filter cartridge of the advanced fast reactor personal protective equipment according to claim 1, characterized in that, The air particle filter paper (5) consists of three layers of gradient filter paper and air distribution plates. The surface layer is made of polypropylene meltblown material with a fiber diameter of 5.2±0.3μm and a basis weight of 28-34g / m². 2 The middle layer is a glass fiber / polytetrafluoroethylene composite membrane with an average pore size of 0.50-0.54μm and a porosity of 80%-86%; the bottom layer is a polyvinylidene fluoride nano-spider web membrane with a fiber diameter of 98±12nm and electrostatic electret treatment.

6. The filter cartridge of the advanced fast reactor personal protective equipment according to claim 5, characterized in that, The air particle filter paper (5) has an air distribution plate installed at the air inlet for uniform airflow. It is made of TC4 titanium alloy with a surface plasma nitriding hardness of HV0.3≥450. Its spiral fin height is 2.00±0.05mm and the tilt angle is optimized to 17.8°.

7. The filter cartridge of the advanced fast reactor personal protective equipment according to claim 1, characterized in that, The impregnated carbon (8) achieves specific adsorption and retention of specific α nuclides in the gas. The substrate is commercially available activated carbon, and the impregnating agent is a metal nitrate of palladium, silver, praseodymium, or cerium, with an impregnating agent content of 20 g / L to 100 g / L. The impregnated carbon (8) after impregnation has a specific surface area ≥1000 m². 2 / g, which gives it the specific adsorption capacity for Po.

8. The filter cartridge of the advanced fast reactor personal protective equipment according to claim 7, characterized in that, The preparation process of impregnated charcoal is as follows: The activated carbon was washed multiple times with tap water, deionized water, and ethanol, and then dried in an oven at 90℃~150℃ for 72 hours before use. Take 5-20 grams of the above activated carbon and place it in a solution of palladium, silver, praseodymium, and cerium metal nitrates. Slowly add ascorbic acid and stir continuously for 24 hours. After draining, wash with ethanol and place in an oven to dry at 100℃-180℃ for 24 hours. After drying, the activated carbon is placed in a tube furnace and calcined at 250℃~400℃ for 1~4 hours in an argon atmosphere for later use.

9. A protective device for human protection against special alpha nuclides in advanced fast reactors, characterized in that, The mask includes a cover (9), a canister connector (10), a water-blocking cover (11), a lens (12), a filter box (13), and a headband (14). The cover (9) adopts a linear single-folded edge according to ergonomics. The lens (12) is provided at the eye position of the cover (9). The water-blocking cover (11) is located inside the cover (9). The canister connector (10) is located on both sides of the cover (9). The canister connector (10) is an integral planar structure, which is convenient for matching and connecting with the filter box (13). During assembly, it is embedded inside the cover (9) to shorten the gap and improve the dynamic airtightness after wearing the mask. The headband (14) is connected to the back of the cover (9). The headband (14) adopts a five-point structure.

10. The apparatus according to claim 9, characterized in that, The cover (9) is made of polyetherimide modified material. The cover (9) has a modular interface on the outside. The water-blocking cover (11) has two inhalation valves and one exhalation valve on the top and bottom. The inner layer of the water-blocking cover (11) has a radial groove structure.

11. A method for using a special alpha nuclide protection device for an advanced fast reactor, characterized in that, Includes the following steps: The weight of the special α-nucleoside filter unit (4) filled with impregnated carbon (8) is 200-700 grams. The impregnated carbon (8), air particle filter paper (5), impregnated carbon (8), air particle filter paper (5), and impregnated carbon (8) are stacked in sequence. All air particle filter unit (5) components are assembled by laser welding, and the annular sealing groove is filled with sealant (6). Align the special α-nucleoside filter unit (4) with the air particle filter unit (5) through a laser welding interface, and then tighten the can lid (1) to the 45°-60° locking position; Helium gas is injected into the inlet, and the concentration at the outlet is monitored by a mass spectrometer. Embed the edge of the water-blocking cover (11) into the slot of the cover body (9); Align the can connector seat (10) with the mounting port on the cover (9) and connect it; Place the lens (12) into the frame and fix the lens (12) to the frame by a strip or a buckle; Align the connecting end of the headband (14) with the headband mounting hole on the cover (9); Align the interface of the filter box (13) with the tank connector seat. The connection method is usually threaded connection or quick plug-in.

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