Nuclear power plant air purifier and manufacturing method thereof

Abstract

The invention discloses a nuclear power plant air purifier and a manufacturing method thereof. The nuclear power plant air purifier comprises a shell and a filtering and adsorbing unit arranged in the shell. The filtration and adsorption unit comprises an activated carbon fiber filter material and a plurality of interlayer brackets; the activated carbon fiber filter material is of a folded structure formed by folding an impregnated and modified activated carbon fiber felt material, the folded structure comprises a plurality of S-shaped folding units which are sequentially connected, and an interlayer support is placed in a folding layer of each S-shaped folding unit. The impregnated and modified activated carbon fiber felt material is folded to form a folded structure to serve as the activated carbon fiber filter material, the adsorption area is increased, the adsorption capacity on radioactive substances is enhanced, and compared with granular activated carbon, the weight is reduced, and the humidity-resistant purification capacity is improved; in the activated carbon fiber filter material, the interlayer brackets are used as flow deflectors to be arranged between two adjacent activated carbon fiber surfaces, so that the two adjacent activated carbon fiber surfaces are prevented from being extruded and attached to each other to influence airflow passing.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear power plant air purification, and in particular to a nuclear power plant air purifier and a manufacturing method thereof. Background Art

[0002] At present, nuclear power plants use iodine adsorbers based on granular coconut shell or coal-based activated carbon to purify nuclear air. The structure is foldable, such as Figure 1 As shown, it consists of a rectangular outer frame, an adsorption bed, a sealing gasket, and screw fasteners. The adsorption bed is arranged in a folded manner in the outer frame. There is a flange with a width of 19 mm on one side of the outer frame, and a sealing gasket is attached. The adsorption bed is filled with coconut shell granular activated carbon.

[0003] The above-mentioned iodine adsorber has the following disadvantages:

[0004] (1) Low purification efficiency: The purification efficiency of granular activated carbon for radioactive methyl iodine gas is generally 99.9% under the conditions of thickness of 51 mm and humidity not higher than 40%, and it is easily affected by temperature and humidity and cannot achieve the purification effect. The acceptance criteria for normal operation of iodine adsorber is 99% or 99.7%. The purification efficiency is only slightly higher than the acceptance criteria, and its long-term operation is obviously not guaranteed.

[0005] (2) Low reliability: Since the granular activated carbon is prone to sedimentation and voids during transportation and handling, and smaller particles are easily blown out during operation, resulting in insufficient filling, the equipment is not very reliable.

[0006] (3) Purification efficiency is too sensitive to humidity: When the humidity exceeds 85%, the purification effect of traditional granular activated carbon drops sharply. Studies have shown that when the humidity reaches 95%, the adsorption purification efficiency drops below 82%. For this reason, a specially designed electric heater circuit and dry air maintenance circuit need to be designed in the ventilation system of nuclear facilities, which increases the complexity of the system and the difficulty of maintenance.

[0007] (4) Short service life: Due to the low initial purification efficiency and the low total adsorption capacity per unit weight of granular activated carbon, its service life is short.

[0008] (5) Heavy weight: An iodine adsorber weighs about 80kg in the early stage, and increases to about 90kg in the later stage of use. This not only makes the handling and installation of the filter inconvenient, but also easily causes the purification test to fail due to installation, and the industrial safety risk during the installation process is very high.

[0009] (6) Solid waste disposal is difficult and costly: Solid waste disposal is charged based on volume and weight, and the disposal cost is much higher than the spare parts and operation and maintenance costs. Summary of the invention

[0010] The technical problem to be solved by the present invention is to provide an improved air purifier for a nuclear power plant.

[0011] The technical solution adopted by the present invention to solve the technical problem is: to provide an air purifier for a nuclear power plant, comprising a housing and a filtering and adsorption unit arranged in the housing; the filtering and adsorption unit comprises an activated carbon fiber filter material and a plurality of interlayer brackets;

[0012] The activated carbon fiber filter material is a pleated structure formed by folding an impregnated and modified activated carbon fiber felt material, and the pleated structure includes a plurality of S-shaped folding units connected in sequence, and an interlayer bracket is placed in the folding layer of each S-shaped folding unit, and the interlayer bracket is arranged between two adjacent activated carbon fiber surfaces.

[0013] In some embodiments, the impregnated modified activated carbon fiber felt is an activated carbon fiber felt impregnated with triethylenediamine.

[0014] In some embodiments, the activated carbon fiber felt is further impregnated with potassium iodide.

[0015] In some embodiments, the interlayer support is a corrugated plate.

[0016] In some embodiments, the interlayer support is a carbon fiber corrugated sheet impregnated with phenolic resin.

[0017] In some embodiments, the outer shell includes a frame body formed by a plurality of flame-retardant wooden boards connected end to end, and reinforcing ribs obliquely connected between two adjacent flame-retardant wooden boards; the filtering and adsorption unit is accommodated inside the frame body.

[0018] In some embodiments, the flame retardant wooden board is a birch board; and the reinforcing ribs are formed of a carbon fiber board or a metal board.

[0019] In some embodiments, the inner surface of each of the flame-retardant wooden boards is provided with sealant, and the sealant bonds the inner surface of the flame-retardant wooden board to the corresponding side of the pleated structure.

[0020] The present invention also provides a method for manufacturing an air purifier for a nuclear power plant, comprising the following steps:

[0021] S1. Folding the impregnated and modified activated carbon fiber felt to form a pleated structure, and placing an interlayer support in the folded layer of each S-shaped folded unit of the pleated structure;

[0022] S2, using a plurality of flame retardant wooden boards to connect and form a frame body with one end open, and providing reinforcing ribs between two adjacent flame retardant wooden boards;

[0023] S3, placing the pleated structure with the interlayer support into the frame body from the open end thereof;

[0024] S4. Use another flame-retardant wooden board to connect to the open end of the frame body to form a closed frame body.

[0025] In some embodiments, the method for manufacturing the nuclear power plant air purifier further comprises the following steps:

[0026] Sealant is successively provided on the inner surface of each of the flame-retardant wooden boards, and the pleated structure is bonded into the frame body by the sealant.

[0027] The beneficial effects of the present invention are as follows: the activated carbon fiber felt material modified by impregnation is folded to form a pleated structure as the activated carbon fiber filter material of the nuclear power plant air purifier, which increases the adsorption area and enhances the adsorption capacity of radioactive substances, reduces the weight and improves the humidity resistance and purification capacity compared with granular activated carbon; the interlayer bracket in the activated carbon fiber filter material is used as a guide plate to separate two adjacent activated carbon fiber surfaces, so as to avoid the two adjacent activated carbon fiber surfaces being squeezed and pressed against each other, which affects the airflow. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0029] Figure 1 It is a schematic diagram of the structure of an iodine filter in the prior art;

[0030] Figure 2 It is a structural schematic diagram of an air purifier for a nuclear power plant according to an embodiment of the present invention;

[0031] Figure 3 It is a structural schematic diagram of a filtering and adsorption unit in an air purifier of a nuclear power plant according to an embodiment of the present invention;

[0032] Figure 4 It is a schematic structural diagram of a shell in a nuclear power plant air purifier according to an embodiment of the present invention;

[0033] Figure 5 It is a schematic diagram of the composition process of a frame body in a nuclear power plant air purifier according to an embodiment of the present invention;

[0034] Figure 6 It is a comparison curve diagram of resistance test results of a nuclear power plant air purifier and a granular activated carbon iodine adsorber according to an embodiment of the present invention;

[0035] Figure 7 It is a comparison curve diagram of purification efficiency of a nuclear power plant air purifier and a granular activated carbon iodine adsorber under different humidity conditions according to an embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0037] like Figures 2 to 4 As shown, an air purifier for a nuclear power plant according to an embodiment of the present invention may include a housing 10 and a filtering and adsorption unit disposed in the housing 10 .

[0038] The filtration and adsorption unit includes an activated carbon fiber filter material and a plurality of interlayer supports 30. The activated carbon fiber filter material is a pleated structure 20 formed by folding an impregnated and modified activated carbon fiber felt material, and the pleated structure 20 includes a plurality of S-shaped folded units 21 connected in sequence. An interlayer support 30 is placed in the folded layer of each S-shaped folded unit 21, which is separated between the activated carbon fiber surfaces on both sides of the folded layer to ensure uniform interlayer distance, uniform air volume distribution, and reduce ventilation resistance.

[0039] It can be understood that the pleated structure 20 can also be formed by connecting a number of U-shaped folding units in sequence.

[0040] For activated carbon fiber filter material, the activated carbon fiber is activated carbon containing carbon fiber, which is activated by high temperature carbonization. Its surface produces nano-scale pores, increasing the specific surface area, thereby changing its adsorption characteristics. Activated carbon fiber is the third generation product after powdered activated carbon and granular activated carbon, with a large specific surface area (1000m 2 / g~3000m 2 / g) and abundant micropores, with the volume of micropores accounting for more than 90% of the total pore volume. Activated carbon fiber has a larger adsorption capacity and faster adsorption kinetics than granular activated carbon. It has high adsorption efficiency for organic matter and anions and cations in liquid and gas phases. It is also resistant to acid and alkali, high temperature and humidity, has strong adaptability, good conductivity and chemical stability, and is an ideal environmentally friendly purification material. However, if the produced activated carbon fiber is directly used for radioactive purification in nuclear power plants, it will be easy to desorb after adsorption, that is, it cannot achieve the purpose of long-term adsorption and retention of radioactive substances. Therefore, it is necessary to impregnate and modify the activated carbon fiber, and fill the modified substance with good complexing properties for radioactive substances into the activated carbon fiber.

[0041] Therefore, in the present invention, the activated carbon fiber is formed into an activated carbon fiber felt material by a felting process, and then the activated carbon fiber felt material is impregnated and modified. Preferably, the activated carbon fiber felt material is impregnated with triethylenediamine, or triethylenediamine and potassium iodide to obtain an impregnated and modified activated carbon fiber felt material.

[0042] The specific operation of the above-mentioned impregnation improvement is as follows: triethylenediamine is formed into high-pressure impregnation steam, and then the triethylenediamine is allowed to enter the micropores of the activated carbon fiber felt in the form of gaseous molecules through blowing or the like, thereby improving the adsorption efficiency and firmness of the activated carbon fiber felt for radioactive substances.

[0043] Furthermore, the activated carbon fiber felt impregnated with triethylenediamine is further impregnated with potassium iodide to enhance the adsorption capacity of radioactive iodine. The operation is as follows: the activated carbon fiber felt impregnated with triethylenediamine is immersed in a potassium iodide aqueous solution, taken out after 10 minutes to 30 minutes, and dried. The potassium iodide aqueous solution is formed by dissolving potassium iodide in pure water. The concentration of the potassium iodide aqueous solution is 3% to 5%.

[0044] In the present invention, the activated carbon fiber filter material is arranged in the housing 10 in a pleated structure 20, which greatly increases the contact area between the activated carbon fiber filter material and the gas to be treated in a limited space. By folding, the originally flat activated carbon fiber forms a pleated structure 20, and the gas passes through more of the activated carbon fiber surface when passing. The folding method of the pleated structure 20 can also guide the airflow to pass through the activated carbon fiber evenly, ensuring that each part of the activated carbon fiber can effectively participate in the adsorption process.

[0045] In the air purifier of a nuclear power plant, the unfolded size of the activated carbon fiber felt is calculated according to the designed air volume, the thickness of the frame of the shell 10, the thickness of the activated carbon fiber and the designed residence time. The activated carbon fiber felt is then folded by a folding tool to form a pleated structure 20. In the air purifier of a nuclear power plant in one embodiment, the parameters of the activated carbon fiber felt are determined as follows: the thickness is 7 mm, the width is 594 mm, and the length is 12400 mm.

[0046] In the pleated structure 20, the interlayer support 30 is arranged between each adjacent and opposite activated carbon fiber surface to prevent the adjacent activated carbon fiber surfaces from being squeezed and pressed against each other during the folding process, thereby affecting the airflow and causing the pressure difference to increase. The interlayer support 30 acts as a guide plate to create a certain gap between the adjacent activated carbon fiber surfaces for airflow to pass through.

[0047] Preferably, the interlayer support 30 is a corrugated plate, which can provide a larger gap space between two adjacent activated carbon fiber surfaces than a flat plate, and better guide the airflow. In the pleated structure 20, the V-shaped grooves on the corrugated plate are respectively oriented toward the inlet and outlet directions of the communicating airflow.

[0048] Further preferably, the interlayer support 30 is a carbon fiber corrugated plate impregnated with phenolic resin. The carbon fiber corrugated plate impregnated with phenolic resin is made by the following method: phenolic resin, water and curing agent are prepared in a mass ratio of 100:100 to 300:2 to 10 to form a phenolic resin impregnation liquid, which is applied on the carbon fiber cloth to form an impregnated carbon fiber cloth; the impregnated carbon fiber cloth is passed between two meshing gear rollers, the two gear rollers are preheated, and the gear rollers rotate relative to each other to roll the impregnated carbon fiber cloth into a wave shape and heat and cure it to form a carbon fiber corrugated plate. The impregnated carbon fiber cloth is covered with release paper or release film before passing through the gear roller.

[0049] The carbon fiber corrugated board has high strength and can effectively support the activated carbon fiber felt material to form a uniform gap. Each square meter of the carbon fiber corrugated board can bear a pressure of 100 to 150 kilograms. The thickness of the carbon fiber corrugated board can be as thin as 0.1 mm to 0.3 mm, with low ventilation resistance.

[0050] The housing 10 further includes a frame body 11 with two opposite open sides, and the filtration adsorption unit is accommodated inside the frame body 11, that is, the pleated structure 20 is accommodated in the internal space of the frame body 11, and the pleated structure 20 faces two open sides of the frame body 11 at two opposite sides, and the interlayer brackets 30 in the pleated structure 20 are also exposed from the two open sides of the frame body 11. During filtration adsorption, the gas to be treated enters from one open side of the frame body 11, passes through the S-shaped folding unit 21 along the interlayer bracket 30, and is finally output from the other open side of the frame body 11.

[0051] The frame body 11 can be formed by connecting a plurality of flame retardant wooden boards 111 end to end, which has a flame retardant effect and can be burned in a high-temperature incinerator to reduce the volume. The flame retardant wooden boards 111 are preferably birch boards.

[0052] Furthermore, the shell 10 also includes a reinforcing rib 12 obliquely connected between two adjacent flame-retardant wooden boards 111. The provision of the reinforcing rib 12 improves the stability and earthquake resistance of the shell. The reinforcing rib 12 is formed of a carbon fiber board to improve the strength and facilitate subsequent incineration and volume reduction. The reinforcing rib 12 can also be formed of a metal plate.

[0053] exist Figure 2 and Figure 4In the illustrated embodiment, the frame body 11 is a rectangular frame formed by connecting four flame-retardant wooden boards 111, and each two adjacent flame-retardant wooden boards 111 are directly connected with reinforcing ribs 12. The reinforcing ribs 12 are specifically connected between the side edges of the two adjacent flame-retardant wooden boards 111, and are also located on the open side of the frame body 11. Preferably, each flame-retardant wooden board 111 is respectively connected with reinforcing ribs 12 on the opposite sides of the two open sides of the frame body 11. On each open side of the frame body 11, the extension lines of the four reinforcing ribs 12 can be connected to form a rectangular frame, which is staggered at 90° with the frame body 11.

[0054] by Figure 2 Taking the placement direction of the nuclear power plant air purifier as an example, the upper and lower two flame-retardant wooden boards 111 of the frame body 11 respectively form the top plate and the bottom plate of the shell 10, and the other two flame-retardant wooden boards 111 form the side plates of the shell. The activated carbon fiber filter material arranged in the form of a pleated structure 20 is vertically accommodated in the frame body 11, and the two side plates correspond to the opposite sides of the folding direction of the pleated structure 20, the height of the pleated structure 20 corresponds to the height of the side plates, the length of the pleated structure 20 corresponds to the length of the top plate and the bottom plate, and the width of the pleated structure 20 corresponds to the width of the top plate and the bottom plate.

[0055] In order to fix the activated carbon fiber filter material in the frame body 11 and improve its stability in the frame body 11 and the connection sealing of the circumferential side, the inner surface of each flame retardant wooden board 111 (that is, the inner circumferential surface of the frame body 11) is provided with sealant. The sealant bonds the inner surface of the flame retardant wooden board 111 to the corresponding side of the pleated structure 20 to avoid the existence of gaps that allow the gas to be treated to pass through without being filtered and adsorbed.

[0056] The sealant needs to have good viscosity, chemical stability and temperature resistance to ensure long-term connection reliability in the working environment of the nuclear power plant air purifier. After baking test, adhesion strength test and hardening time test and other related tests, flame retardant and high hardness potting glue was selected as the sealant.

[0057] In some embodiments, the nuclear power plant air purifier further includes a sealing gasket 40, which is disposed on an open side of the frame body 11 and fixedly connected to the periphery of the open side of the frame body 11. The sealing gasket 40 is used to achieve a sealed connection between the nuclear power plant air purifier and the ventilation system or gas delivery equipment when the two are docked.

[0058] The sealing gasket 40 is made of high temperature resistant and flame retardant silicone rubber or closed silicone sponge rubber, and has a D-shaped cross section.

[0059] refer to Figure 2-Figure 4 A method for manufacturing an air purifier for a nuclear power plant according to an embodiment of the present invention may include the following steps:

[0060] S1. Fold the impregnated and modified activated carbon fiber felt to form a pleated structure, and place an interlayer support in the folded layer of each S-shaped folded unit of the pleated structure.

[0061] Firstly, the activated carbon fiber is made into an activated carbon fiber felt material through a needle punching process, and then the activated carbon fiber felt material is impregnated and modified: the activated carbon fiber felt material is impregnated with triethylenediamine, or triethylenediamine and potassium iodide, to obtain an impregnated and modified activated carbon fiber felt material.

[0062] The impregnated and modified activated carbon fiber felt material can be folded in an S-shaped manner by a folding tool to form a pleated structure 20 formed by connecting a plurality of S-shaped folding units. An interlayer support 30 is placed in each folded layer; the pleated structure 20 and the interlayer support 30 form a filtering and adsorption unit.

[0063] S2. A plurality of flame-retardant wooden boards 111 are connected to form a frame body 11 with one end open, and reinforcing ribs 12 are arranged between two adjacent flame-retardant wooden boards 111 .

[0064] S3. Place the pleated structure 20 with the interlayer support 30 into the frame body 11 from the open end thereof.

[0065] S4. Use another flame-retardant wooden board 111 to connect to the open end of the frame body 11 to form a closed frame body 11.

[0066] In some embodiments, the method for manufacturing an air purifier for a nuclear power plant further comprises the following steps:

[0067] Sealant is successively provided on the inner surface of each flame retardant wood board 111 , and the outer peripheral surface of the pleated structure 20 is adhered to the frame body 11 by the sealant, and the outer peripheral surface of the pleated structure 20 is sealed and connected with the inner surface of the frame body 11 .

[0068] In a preferred embodiment, a frame body 11 with one end open is first assembled, such as Figure 5 The U-shaped frame body shown has reinforcing ribs 12. The flame-retardant wood board 111 at the bottom can be used as a bottom plate, on which sealant is applied. To prevent the sealant from flowing out of the bottom plate, a sealant baffle is pre-set on the bottom plate; the thickness of the sealant applied reaches 3mm to 8mm.

[0069] Place the filter adsorption unit vertically downward into the U-shaped frame body so that the sealant completely immerses the downward end surface of the filter adsorption unit.

[0070] After the sealant is cured, the U-shaped frame is turned over so that its open end faces downward, and is fitted onto another flame-retardant wooden board 111 (serving as a top plate) pre-coated with sealant. While the open end of the U-shaped frame is connected to the flame-retardant wooden board 111 serving as the top plate, the end face of the filter adsorption unit corresponding to the open end of the U-shaped frame is also immersed in the sealant in the top plate.

[0071] After the sealant is cured, the frame body can be turned sideways so that the other two flame-retardant wooden boards 111 serving as side panels face downward, and sealant is poured or applied into them so that the corresponding sides of the filter adsorption unit are immersed in the sealant. After the sealant is cured, the sides of the filter adsorption unit are bonded to the side panels.

[0072] Through the above-mentioned sealing glue injection and curing bonding, the surrounding surfaces of the filtration and adsorption unit are bonded and sealed to the inner surface of the frame body 11 .

[0073] In addition, the sealant should be applied with uniform thickness and without bubbles. The surrounding surfaces of the filtration and adsorption unit are bonded to the inner surface of the frame 11 by the sealant, and appropriate pressure is applied to make them in close contact to promote the curing of the sealant.

[0074] The performance of the nuclear power plant air purifier of the present invention is verified below.

[0075] 1) Resistance test

[0076] The nuclear power plant air purifier of the present invention is installed on a ventilation system test bench, and a thermal anemometer is used to measure the air volume flowing through the nuclear power plant air purifier, and a differential pressure gauge is used to measure the upstream and downstream differential pressure of the nuclear power plant air purifier. The test bench is adjusted to adjust the damper to obtain the differential pressure of the nuclear power plant air purifier under different air volumes, thereby evaluating the airflow resistance performance index of the nuclear power plant air purifier. The test results are shown in Table 1 below:

[0077] Table 1

[0078]

[0079]

[0080] According to the reference standard, the filter resistance is not more than 360 Pa at the rated air volume. 3 The resistance under the working condition of 1.577Nm / h is 171Pa, which meets the standard requirements.

[0081] Taking the filter using granular activated carbon as a comparative example, an airflow resistance test was carried out on the same test bench. The test results of the comparative example and the present invention were compared. Figure 6 shown.

[0082] from Figure 6By comparison, it can be seen that under the same air volume, the resistance of the nuclear power plant air purifier of the present invention is smaller than that of the filter using granular activated carbon, which is beneficial to the system air volume adjustment and matching and reduces the fan energy consumption.

[0083] 2) Methyl iodide purification efficiency test

[0084] The nuclear power plant air purifier of the present invention is installed on a ventilation system test bench, and the air volume is adjusted to the rated air volume. A humidification regulator is connected to the entrance of the test bench to adjust different humidity levels. A certain concentration of methyl iodide gas is injected upstream as a tracer, and a special tester is used to simultaneously collect and measure the real-time concentration of the upstream and downstream of the purifier, and the total amount of upstream methyl iodine injection and the total amount of downstream leakage are cumulatively calculated, thereby calculating the purification efficiency of the purifier.

[0085] The test results of methyl iodide purification efficiency under different humidity conditions are shown in Table 2 below:

[0086] Table 2

[0087] Relative humidity 37.3％ 59.7％ 85.6％ 92％ Purification efficiency 99.991％ 99.991％ 99.953％ 99.924％

[0088] The purification efficiency of the granular activated carbon iodine filter as a comparative example is shown in Table 3 below:

[0089] Table 3

[0090] Relative humidity 62.7％ 72.3％ 88.6％ Purification efficiency 99.961％ 99.900％ 99.482％

[0091] From the results in Table 2 and Table 3, it can be seen that under the condition of 90% humidity, the purification efficiency of the nuclear power plant air purifier of the present invention for methyl iodide is still greater than 99.9%, far exceeding the purification capacity of granular activated carbon.

[0092] The comparison curve of the purification effect between the nuclear power plant air purifier of the present invention and the granular activated carbon iodine filter is as follows: Figure 7 As shown. Figure 7 By comparison, it can be seen that with the increase of relative humidity, the purification effect of the granular activated carbon iodine filter decreases significantly, while the purification effect of the nuclear power plant air purifier of the present invention is relatively stable.

[0093] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A nuclear power plant air purifier, characterized in that: It comprises a shell and a filtering and adsorption unit arranged in the shell; the filtering and adsorption unit comprises an activated carbon fiber filter material and a plurality of interlayer supports; The activated carbon fiber filter material is a pleated structure formed by folding an impregnated and modified activated carbon fiber felt material, and the pleated structure includes a plurality of S-shaped folding units connected in sequence, and an interlayer bracket is placed in the folding layer of each S-shaped folding unit, and the interlayer bracket is arranged between two adjacent activated carbon fiber surfaces.

2. The nuclear power plant air purifier according to claim 1, characterized in that: The impregnated modified activated carbon fiber felt material is an activated carbon fiber felt material impregnated with triethylenediamine.

3. The nuclear power plant air purifier according to claim 2, characterized in that: The activated carbon fiber felt material is also impregnated with potassium iodide.

4. The nuclear power plant air purifier according to claim 1, characterized in that: The interlayer support is a corrugated plate.

5. The nuclear power plant air purifier according to claim 4, characterized in that: The interlayer support is a carbon fiber corrugated plate impregnated with phenolic resin.

6. The nuclear power plant air purifier according to any one of claims 1 to 5, characterized in that: The shell comprises a frame body formed by connecting a plurality of flame-retardant wooden boards end to end, and reinforcing ribs obliquely connected between two adjacent flame-retardant wooden boards; the filtering and adsorption unit is accommodated inside the frame body.

7. The nuclear power plant air purifier according to claim 6, characterized in that: The flame retardant wooden board is a birch board; the reinforcing ribs are formed by a carbon fiber board or a metal board.

8. The nuclear power plant air purifier according to claim 6, characterized in that: The inner surface of each of the flame-retardant wooden boards is provided with sealant, and the sealant bonds the inner surface of the flame-retardant wooden board to the corresponding side of the pleated structure.

9. A method for manufacturing an air purifier for a nuclear power plant according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Folding the impregnated and modified activated carbon fiber felt to form a pleated structure, and placing an interlayer support in the folded layer of each S-shaped folded unit of the pleated structure; S2, using a plurality of flame retardant wooden boards to connect and form a frame body with one end open, and providing reinforcing ribs between two adjacent flame retardant wooden boards; S3, placing the pleated structure with the interlayer support into the frame body from the open end thereof; S4. Use another flame-retardant wooden board to connect to the open end of the frame body to form a closed frame body.

10. The method for manufacturing an air purifier for a nuclear power plant according to claim 9, characterized in that: The following steps are also included: Sealant is successively provided on the inner surface of each of the flame-retardant wooden boards, and the pleated structure is bonded into the frame body by the sealant.

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