Exhaust filtering device for nuclear power facility

Abstract

The invention relates to the technical field of nuclear facility exhaust, in particular to an exhaust filtering device for a nuclear power facility, which comprises an air inlet pipe, an air outlet pipe, a general filtering system, a special filtering system, a transition pipe, an exhaust fan, a first valve, a second valve and a third valve, the universal filtering system is used for filtering gas; the special filtering system is used for filtering at least predetermined substances; the special filtering system and the general filtering system are communicated to form a whole, one end of the whole is communicated with the air inlet pipe, and the other end is communicated with the air outlet pipe; the transition pipe and the special filtering system are arranged in parallel, one end of the transition pipe is communicated with one end of the general filtering system, and the other end is communicated with the air inlet pipe or the air outlet pipe; the exhaust fan is arranged at one end of the general filtering system; the first valve is arranged at the air inlet end of the special filtering system; the second valve is provided with a transition pipe; the third valve is provided with an air outlet pipe; the exhaust filtering device for the nuclear power facility is long in service life and low in maintenance cost.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear facility exhaust technology, and in particular to an exhaust filter device for nuclear power facilities. Background Art

[0002] In order to meet the strict control requirements of nuclear power plants on the release of radioactive doses to the outside world, the exhaust of the control area of ​​the nuclear island building must be carefully planned; after being purified by the exhaust filtration device, the exhaust air should be discharged through a high chimney; the core function of these filtering devices is to remove conventional pollutants and special pollutants in the exhaust air.

[0003] In the control area of ​​the nuclear island building, although common pollutants continue to exist in some rooms, the probability of special pollutants appearing is relatively low, and they usually only leak in accidents, equipment failures or operational errors; therefore, during the normal operation of the nuclear power plant, there is no need to continuously filter special pollutants in the exhaust system; however, the current exhaust filter device is an integrated design, so that even if there are no special pollutants, the entire exhaust filter device needs to continue to operate, which not only shortens the effective life of the exhaust filter device when dealing with special pollutants, but also increases maintenance costs. Summary of the invention

[0004] In view of the above shortcomings of the prior art, an object of the present invention is to provide an exhaust air filtering device for a nuclear power facility, which has a long service life and low maintenance cost.

[0005] To achieve the above-mentioned object and other related objects, the present invention provides an exhaust air filtering device for a nuclear power facility, comprising an air inlet pipe, an air outlet pipe, a general filtering system, a special filtering system, a transition pipe, an exhaust fan, a first valve, a second valve and a third valve;

[0006] The universal filtering system is used to filter the delivered gas; the dedicated filtering system is used to filter at least predetermined substances in the delivered gas; the dedicated filtering system and the universal filtering system are connected to form a whole, one end of which is connected to the air inlet pipe, and the other end is connected to the air outlet pipe; the transition pipe is arranged in parallel with the dedicated filtering system, and one end of the transition pipe is connected to one end of the universal filtering system, and the other end is connected to the air inlet pipe or the air outlet pipe; the exhaust fan is arranged at one end of the universal filtering system; the first valve is arranged at the air inlet end of the dedicated filtering system; the second valve is arranged in the transition pipe; the third valve is arranged in the air outlet pipe.

[0007] In one embodiment of the present invention, the universal filtering system comprises a first pre-filter and a first air filter which are sequentially arranged in series.

[0008] In one embodiment of the present invention, the dedicated filtration system comprises at least an electric heater and an iodine adsorber which are sequentially connected in series.

[0009] In one embodiment of the present invention, the dedicated filtering system further comprises a second filter and a second air filter which are sequentially arranged in series.

[0010] In one embodiment of the present invention, the universal filtering system and the dedicated filtering system are integrated.

[0011] In one embodiment of the present invention, the electric heater is disposed downstream of the second air filter.

[0012] In one embodiment of the present invention, an exhaust fan is further included, and the exhaust fan is arranged upstream of the third valve adjacent to the air outlet pipe.

[0013] In one embodiment of the present invention, the exhaust fan is a variable frequency fan.

[0014] In one embodiment of the present invention, the air inlet pipe, the second filter, the second air filter, the electric heater, the iodine adsorber, the first pre-filter and the first air filter are arranged in series in sequence, one end of the transition pipe is connected to the air inlet pipe, and the other end is connected to between the iodine adsorber and the first pre-filter.

[0015] In one embodiment of the present invention, at least one of the first valve, the second valve, and the third valve is an electric isolation valve.

[0016] In summary, the present invention connects one end of the transition pipe with one end of the universal filter system, and the other end of the transition pipe with the air inlet pipe or the air outlet pipe, and uses the first valve and the second valve, so that the exhaust air can selectively pass through the dedicated filter system or not pass through the dedicated filter system. When there is no predetermined substance in the air inlet pipe, the first valve is closed, and the second valve and the third valve are opened, so that the exhaust air is discharged from the air inlet pipe, through the transition pipe, the universal filter system to the air outlet pipe, and can filter ordinary substances such as aerosols in the exhaust air; when there is a predetermined substance in the air inlet pipe, the first valve and the third valve are opened. The door is opened, and the second valve is closed, so that the exhaust air is discharged from the air inlet pipe, through the special filtration system, the universal filtration system to the air outlet pipe, which can filter conventional pollutants such as radioactive aerosols and special substances such as iodine in the exhaust air, thereby extending the service life of the special filtration system, thereby ensuring the service life of the exhaust filtration device for nuclear power facilities. At the same time, the universal filtration system and the special filtration system can be arranged on the same line, avoiding the defect of large floor space when they are arranged in parallel; since the special filtration system is used less frequently and for less time, the special filtration system does not require frequent maintenance, which reduces maintenance costs and improves overall reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is a schematic structural diagram of an exhaust filter device for a nuclear power facility according to an optional embodiment of the present invention;

[0019] Figure 2 This is a schematic structural diagram of an exhaust filter device for a nuclear power facility according to another optional embodiment of the present invention;

[0020] Figure 3 for Figure 2 Detailed structural diagram of the exhaust air filtration device for nuclear power facilities;

[0021] Figure 4 for Figure 1 Detailed structural diagram of the exhaust air filtration device for nuclear power facilities;

[0022] Figure 5 It is a detailed structural schematic diagram of the exhaust filter device for nuclear power facilities in the improvement process of the present invention;

[0023] Component number description: pre-filter 31a, high efficiency filter No. 1 32a, booster fan No. 1 6a, electric heater No. 1 41a, iodine adsorber No. 1 42a, high efficiency filter No. 2 44a, booster fan No. 2 6b, air inlet pipe 1, air outlet pipe 2, universal filtration system 3, first pre-filter 31, first air filter 32, special filtration system 4, electric heater 41, iodine adsorber 42, second pre-filter 43, second air filter 44, transition duct 5, exhaust fan 6, first valve 7, second valve 8, third valve 9, outer wall of box body 100, fourth valve 10. DETAILED DESCRIPTION

[0024] The following is an explanation of the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the features in the following embodiments and the embodiments can be combined with each other without conflict. It should also be understood that the terms used in the embodiments of the present invention are intended to describe specific embodiments, rather than to limit the scope of protection of the present invention. The test methods for which specific conditions are not specified in the following examples are usually carried out under conventional conditions or according to the conditions recommended by the manufacturers.

[0025] See also Figures 1 to 5 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical content disclosed by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0026] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise specified in the present invention, both endpoints of each numerical range and any value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention are familiar to those skilled in the art and the description of the present invention, and any methods, equipment and materials of the prior art similar or equivalent to the methods, equipment and materials described in the embodiments of the present invention can also be used to implement the present invention.

[0027] Before the improvement in this case, the existing exhaust air filter device had to operate its iodine adsorber 42 continuously online even when no iodine contamination occurred, which reduced the service life of the iodine adsorber 42 and required frequent replacement of the adsorption medium, which not only reduced the service life of the exhaust air filter device, but also increased the frequency of maintenance and increased maintenance costs. It should be understood that the technology before the improvement and the technology in the improvement process described in this case do not represent the existing technology, because some of the technology is still confidential and has not been disclosed. In the process of improvement in this case, such as Figure 5As shown, it consists of a conventional filtration module (generally including a pre-filter 31a, a No. 1 high-efficiency filter 32a, valves related to normal exhaust, a No. 1 booster fan 6a for normal exhaust and related valves) and an iodine removal module (generally including valves of an iodine removal circuit, a No. 1 electric heater 41a, a No. 1 iodine adsorber 42a, a No. 2 high-efficiency filter 44a, a No. 2 booster fan 6b, a manual isolation valve at the fan inlet, and a check valve at the fan outlet). When there is no iodine pollution in the exhaust air, the electric isolation valve of the conventional filtration module is opened, the electric isolation valve of the iodine removal module is closed, the No. 2 booster fan 6b does not run, and the exhaust air is discharged after being purified by the pre-filter 31a and the No. 1 high-efficiency filter 32a; when there is iodine pollution in the exhaust air, the electric isolation valve of the conventional filtration module is closed, the electric isolation valve of the iodine removal module is opened, the No. 1 iodine adsorber 42a is put into operation, and the exhaust air is discharged after being purified by the pre-filter 31a, the No. 1 high-efficiency filter 32a, the No. 1 electric heater 41a, the No. 1 iodine adsorber 42a, and the No. 2 high-efficiency filter 44a. Therefore, when the exhaust filter device is in use, when iodine pollution does not occur, the iodine removal module does not need to be put into operation, which can extend the service life of the iodine removal module. However, since the iodine removal module is connected in parallel with the conventional filter module using an air duct to form a separate filter structure, on the one hand, the overall floor space of the exhaust filter device is increased. On the other hand, this solution requires the addition of a second booster fan 6b to overcome the resistance of the iodine removal module. In addition, the iodine removal module and the conventional filter module are arranged in parallel, which increases the control complexity and reduces the reliability.

[0028] See also Figure 1 or Figure 2 The present invention provides an exhaust air filtering device for a nuclear power facility, comprising an air inlet pipe 1, an air outlet pipe 2, a general filtering system 3, a special filtering system 4, a transition pipe 5, an exhaust fan 6, a first valve 7, a second valve 8 and a third valve 9;

[0029] The universal filter system 3 is used to filter the delivered gas; the dedicated filter system 4 is used to filter at least predetermined substances in the delivered gas; the dedicated filter system 4 and the universal filter system 3 are connected to form a whole, one end of which is connected to the air inlet pipe 1, and the other end is connected to the air outlet pipe 2; the transition pipe 5 is arranged in parallel with the dedicated filter system 4, and one end of the transition pipe 5 is connected to one end of the universal filter system 3, and the other end of the transition pipe 5 is connected to the air inlet pipe 1 or the air outlet pipe 2; the exhaust fan 6 is arranged at one end of the universal filter system 3; the first valve 7 is arranged at the air inlet end of the dedicated filter system 4; the second valve 8 is arranged on the transition pipe 5; the third valve 9 is arranged on the air outlet pipe 2.

[0030] It should be noted that the air inlet pipe 1 can be changed into an air inlet, and the air outlet pipe 2 can be changed into an air outlet; the general filter system 3 is used to filter the predetermined common gas delivered, such as radioactive aerosol; the special filter system 4 is used to filter at least predetermined pollutants in the delivered gas, such as iodine, and of course, the special filter system 4 can also filter the predetermined common gas delivered; the special filter system 4 and the general filter system 3 are connected, that is, the special filter system 4 and the general filter system 3 can be connected along a straight line, wherein the general filter system 3 and the special filter system 4 can be set with one or more, and the general filter system 3 can include a pre-filter, a high-efficiency filter and / or an exhaust filter fan; the special filter system 4 can include an electric heater 41, an iodine adsorber 42 and / or a high-efficiency filter and / or a booster fan; the general filter system 3 can be directly connected to the air inlet pipe 1, or the special filter system 4 can be directly connected to the air inlet pipe 1; the transition pipe 5 is arranged in parallel with the special filter system 4, so that the transition pipe 5 can replace the special filter system 4 at any time and connect with the general filter system 3.

[0031] In this case, since some rooms in the control area of ​​the nuclear island building of the nuclear power plant continue to be contaminated by radioactive aerosols, the probability of iodine contamination in these rooms is relatively small, and generally only occurs in the event of an accident, a process equipment failure, or a human operator error; therefore, under normal operating conditions of the nuclear power plant, the dedicated filter system 4 in the exhaust system of the control area does not need to be put into operation continuously. In response to this problem, in this case, by connecting one end of the transition pipe 5 to one end of the universal filter system 3, and the other end of the transition pipe 5 to the air inlet pipe 1 or the air outlet pipe 2, combined with the use of the first valve 7 and the second valve 8, the exhaust air can selectively pass through the dedicated filter system 4 or not. When there is no predetermined substance in the air inlet pipe 1, the first valve 7 is closed, and the second valve 8 and the third valve 9 are opened, so that the exhaust air is discharged from the air inlet pipe 1, through the transition pipe 5, the universal filter system 3 to the air outlet pipe 2, and can filter out common substances such as radioactive aerosols in the exhaust air; when there is a predetermined substance in the air inlet pipe 1 When the exhaust air is exhausted, the first valve 7 and the third valve 9 are opened, and the second valve 8 is closed, so that the exhaust air is discharged from the air inlet pipe 1, through the dedicated filter system 4 and the universal filter system 3 to the air outlet pipe 2, which can filter ordinary substances such as radioactive aerosols and special substances such as iodine in the exhaust air, thereby extending the service life of the dedicated filter system 4, thereby ensuring the service life of the exhaust filter device for nuclear power facilities. At the same time, the universal filter system 3 and the dedicated filter system 4 can be arranged on the same line, avoiding the defect of occupying a large area when arranged in parallel; and because the dedicated filter system 4 does not require frequent maintenance, the maintenance cost is low and the overall reliability is improved.

[0032] See also Figure 3 or Figure 4As an optional embodiment of the present case, the universal filtering system 3 includes a first pre-filter 31 and a first air filter 32 which are sequentially arranged in series.

[0033] It should be noted that by arranging the first pre-filter 31 and the first air filter 32 in series, more particles can be effectively intercepted, and the filtering efficiency of the entire system can be improved; since the first pre-filter 31 can intercept larger particles, the burden of the subsequent first air filter 32 is reduced, and its service life is extended, and by adjusting the number ratio and combination of the first pre-filter 31 and the first air filter 32, the filtering effect can be adjusted more flexibly. Among them, the first pre-filter 31 can be a FIP filter, and the FIP filter can filter larger particles of impurities, for example, impurities larger than 1 mm; the first air filter 32 can be a HEPA filter, and the HEPA filter is in accordance with the EN1822 standard, and can filter particles with a particle size of 0.3 μm and the filtering efficiency is higher than 99.97%.

[0034] See also Figure 3 or Figure 4 As an optional embodiment of the present invention, the dedicated filtering system 4 at least includes an electric heater 41 and an iodine adsorber 42 which are sequentially connected in series.

[0035] It should be noted that by arranging the electric heater 41 and the iodine adsorber 42 in series, the adsorption efficiency of radioactive pollutants can be effectively improved. The electric heater 41 can heat the gas to a certain temperature, which is beneficial to the adsorption process of the iodine adsorber 42. The electric heater 41 can adjust the heating power according to actual needs to avoid overheating, thereby reducing energy consumption. At the same time, the iodine adsorber 42 also has a certain thermal insulation performance, which can reduce heat loss. According to different needs and environmental conditions, the filtering effect can be flexibly adjusted by adjusting the heating power of the electric heater 41 and the adsorption capacity of the iodine adsorber 42. Among them, the electric heater 41 can be an EHC heater, also known as an electromagnetic heater. In the process of converting electrical energy into thermal energy, the thermal efficiency of the EHC heater is very high, which can reach 95%; compared with traditional resistance heating, the EHC heater does not need to conduct heat through matter, thereby reducing energy loss. The EHC heater can heat up quickly within a few seconds after starting, quickly increase the temperature during exhaust gas purification, and effectively reduce pollutant emissions during the cold start stage. Using an EHC heater can significantly reduce harmful emissions such as nitrogen oxides and hydrocarbons. And by precisely controlling the heating process, the EHC heater can save a lot of energy, 30%-70% more energy than resistance heating. The iodine adsorber 42 can be a FII adsorber, which complies with the NB / T20039.13 standard and can adsorb radioactive iodine in the air, thereby reducing the level of gaseous radioactive emissions and ensuring the habitability of the predetermined environment; the FII adsorber has a high adsorption efficiency for radioactive iodine, and when the adsorber is used, the airflow distribution is uniform, the resistance is small, and the operation is convenient.

[0036] See also Figure 3 or Figure 4 As an optional embodiment of the present case, the dedicated filtering system 4 further includes a second pre-filter 43 and a second air filter 44 which are sequentially arranged in series.

[0037] It should be noted that by sequentially arranging the electric heater 41, the iodine adsorber 42, the second pre-filter 43 and the second air filter 44 in series; or sequentially arranging the second pre-filter 43, the second air filter 44, the electric heater 41 and the iodine adsorber 42 in series, more pollutants can be effectively intercepted and the filtering efficiency of the entire system can be improved. Due to the serial arrangement of the second pre-filter 43 and the second air filter 44, the wear and aging rate of a single filter can be reduced, its service life can be extended, and the purpose of filtering target pollutants can be achieved. The reasonable combination of the second pre-filter 43 and the second air filter 44 can reduce the replacement frequency and maintenance cost of a single device. According to different needs and environmental conditions, the filtering effect can be flexibly adjusted by adjusting the proportion and combination of each filter. Among them, the second pre-filter 43 can be a FIP filter; the second air filter 44 can be a HEPA filter.

[0038] See also Figure 3 or Figure 4 As an optional embodiment of the present case, the universal filtration system 3 and the dedicated filtration system 4 are integrally arranged, that is, the universal filtration system 3 and the dedicated filtration system 4 share a box outer wall 100, that is, the various components in the universal filtration system 3 and the dedicated filtration system 4 can share a box outer wall 100, specifically, the first pre-filter 31, the first air filter 32, the electric heater 41, the electric adsorber and / or the second pre-filter 43 and / or the second air filter 44 all share a box outer wall 100.

[0039] It should be noted that by sharing a box outer wall 100, the installation space can be effectively saved and the equipment footprint can be reduced; sharing a box outer wall 100 can reduce the number of connection points and interfaces during the installation process, simplify the installation process, and improve the installation efficiency; since a box outer wall 100 is shared, the material usage and manufacturing costs can be reduced, and the transportation and storage costs can also be reduced; sharing a box outer wall 100 can make the entire filtration system more compact and beautiful; sharing a box outer wall 100 can facilitate overall cleaning and maintenance, thereby improving maintenance efficiency and management convenience.

[0040] See also Figure 3 or Figure 4 As an optional embodiment of the present invention, the electric heater 41 is arranged downstream of the second air filter 44; that is, the dedicated filtering system 4 is arranged in the order of the second pre-filter 43, the second air filter 44, the electric heater 41 and the iodine adsorber 42. In the present invention, by arranging the electric heater 41 downstream of the second air filter 44, the second pre-filter 43 and the second air filter 44 can effectively absorb, filter and intercept a large number of normal pollutants, thereby reducing the attachment of normal pollutants to the electric heater 41 and the iodine adsorber 42, avoiding damage to the electric heater 41, and increasing the service life of the electric heater 41 and the iodine adsorber 42; the electric heater 41 can heat the gas to a certain temperature, which is beneficial to the adsorption process of the iodine adsorber 42; at the same time, the electric heater 41 can adjust the heating power according to actual needs to avoid overheating, thereby reducing energy consumption.

[0041] See also Figure 3 or Figure 4 As an optional embodiment of the present case, the exhaust fan 6 is arranged upstream of the third valve 9 near the air outlet pipe 2.

[0042] It should be noted that, by arranging the exhaust fan 6 upstream of the third valve 9 at the air outlet pipe 2, on the one hand, only one exhaust fan 6 is required to meet the use, thereby reducing the manufacturing cost of the exhaust filter device for nuclear power facilities; on the other hand, the exhaust fan 6 is arranged upstream of the third valve 9, so that after the third valve 9 is closed, the leakage of radioactive substances in the exhaust air can be avoided, which is beneficial to subsequent maintenance and inspection.

[0043] See also Figure 3 or Figure 4 As an optional embodiment of the present case, the exhaust fan 6 is a variable frequency fan.

[0044] It should be noted that the variable frequency fan can adjust the speed according to actual needs, thereby adjusting the air volume. When a large amount of exhaust air is not required, the speed of the exhaust fan 6 can be reduced to reduce energy consumption. This adjustment method is more energy-efficient than the traditional fixed-speed fan. The variable frequency fan has low noise when running at a low speed, which helps to improve the environment during exhaust; the variable frequency fan can be precisely controlled by the frequency converter to achieve precise adjustment of the air volume, which helps to meet the needs of different scenarios; for example, the variable frequency fan can meet the wind pressure requirements in both normal exhaust filtration and iodine removal exhaust filtration modes.

[0045] See also Figure 1 or Figure 2 or Figure 3 or Figure 4 As an optional embodiment of the present case, at least one of the second valve 8 and the third valve 9 is an electric isolation valve.

[0046] It should be noted that, generally, a predetermined substance detector will be set at the air inlet. For example, if it is for iodine removal, the predetermined substance detector can be an online monitoring system based on electrochemical or spectral technology. Specifically, the ERUN-PG51 series fixed gas alarm with electrochemical sensors can be used, which can simultaneously detect and display the concentration values ​​of multiple gases (including iodine), automatically sound and light alarm when exceeding the standard, and can interlock and automatically control the start and stop of the exhaust fan and the electric isolation valve; the electric isolation valve is a gate valve with an electric actuator, which drives the valve stem and the gate plate to move up and down by driving the motor to realize the opening and closing of the valve, and can control the flow direction and flow rate of the fluid medium. The electric isolation valve can be remotely controlled by a computer or controller, thereby eliminating the trouble of manual adjustment or opening and closing; the electric isolation valve has an overload protection function, which can automatically close under abnormal conditions to ensure the safe operation of the system; the electric isolation valve has good adjustment performance, and the valve opening can be adjusted as needed to meet the needs of different working conditions. The first valve 7 can be a shutter valve, specifically an electric shutter valve; the shutter valve can also be rectangular, and the shutter valve has the advantages of uniform flow, small opening and closing torque, sensitive action, reliable performance, large caliber, light weight, and small leakage; the first valve 7 can also be an electric isolation valve or other valve that meets the use requirements. When the first valve 7 is an electric isolation valve, the universal filter system 3 and the special filter system 4 are connected through the first pipe, that is, the first air filter 32 in the universal filter system 3 and the electric heater of the special filter system are connected through the first pipe, and the electric isolation valve is arranged on the first pipe.

[0047] See also Figure 2 or Figure 3 As an optional embodiment of the present case, the air inlet pipe 1, the general filter system 3, the special filter system 4 and the air outlet pipe 2 are arranged in series in sequence, and a fourth valve 10 is provided at the air inlet pipe 1; when it is necessary to inspect and repair the exhaust filter device for the nuclear power facility, the fourth valve 10 can be closed.

[0048] As an optional embodiment of the present case, the general filter system 3 is mainly used to absorb aerosol pollutants in the transported gas; the special filter system 4 is mainly used to absorb radioactive pollutants, such as iodine, in the transported gas, so that different filtering methods can be used for different types of pollutants; the general filter system 3 can handle aerosol pollutants, such as dust, etc., while the special filter system 4 can handle radioactive pollutants, such as iodine, etc. By using different filter systems, a suitable filter system can be selected according to actual needs to avoid unnecessary waste.

[0049] The exhaust air filter device for nuclear power facilities of the present invention can be directly applied to the exhaust system of aerosol pollution and iodine pollution control areas in nuclear power plants, so as to filter and purify aerosol and iodine pollution in the exhaust air of the contaminated area when radioactive pollution occurs in the plant area, so as to ensure that the radioactive dose of the exhaust air in the control area does not exceed the requirements of relevant national standards and achieve the purpose of being as low as reasonably feasible.

[0050] See also Figure 4 As an optional embodiment of the present case, the air inlet pipe 1, the second pre-filter 43, the second air filter 44, the electric heater 41, the iodine adsorber 42, the first pre-filter 31 and the first air filter 32 are arranged in series in sequence, one end of the transition pipe 5 is connected to the air inlet pipe 1, and the other end of the transition pipe 5 is connected to between the iodine adsorber 42 and the first pre-filter 31.

[0051] It should be noted that, in this solution, the universal filtering system 3 includes a first pre-filter 31 and a first air filter 32; the dedicated filtering system 4 includes a second pre-filter 43, a second air filter 44, an electric heater 41 and an iodine adsorber 42; through this arrangement, when there is a predetermined substance in the exhaust air, the first valve 7 and the third valve 9 are opened, and the second valve 8 is closed, so that the exhaust air passes through the air inlet pipe 1, the second pre-filter 43, the second air filter 44, the electric heater 41, the iodine adsorber 42, the first pre-filter 31 and the first air filter 32, and the air outlet pipe 2 in sequence to filter the exhaust air. out, to achieve filtering of conventional pollutants and predetermined substances; when the exhaust air does not contain the predetermined substances or the dedicated filtering system 4 needs to be inspected and repaired, the second valve 8 and the third valve 9 are opened and the first valve 7 is closed, so that the exhaust air is filtered and discharged in sequence through the air inlet pipe 1, the transition pipe 5, the first pre-filter 31 and the first air filter 32, and the air outlet pipe 2, to achieve filtering of conventional pollutants; it should be understood that in the normal exhaust and iodine removal exhaust processes, the third valve 9 is in the normally open state; when inspected and repaired, the first valve 7, the second valve 8 and the third valve 9 are opened and closed according to actual needs.

[0052] See also Figure 3This example is different from the above-mentioned embodiment. The universal filtering system 3 includes a first pre-filter 31 and a first air filter 32; the special filtering system 4 includes an electric heater 41 and an iodine adsorber 42; the air inlet pipe 1, the first pre-filter 31, the first air filter 32, the electric heater 41, the iodine adsorber 42, and the air outlet pipe 2 are arranged in sequence, and one end of the transition pipe 5 is connected between the first air filter 32 and the electric heater 41; the other end of the transition pipe 5 is connected to the air outlet pipe 2; the first valve 7 is arranged between the electric heater 41 and the iodine adsorber 42; the second valve 8 is arranged on the transition pipe 5; the third valve 9 is arranged on the air outlet pipe 2; a fourth valve 10 is arranged upstream of the first pre-filter 31, and the first valve 7 and / or the second valve 8 and / or the third valve 9 and / or the fourth valve 10 are electric isolation valves. Compared with the previous solution, this solution adds a fourth valve 10, reduces the second pre-filter 43 and the second air filter 44, and reduces the overall cost. Although the filtering efficiency of common pollutants is slightly reduced, it does not affect the filtering of aerogel and iodine in the exhaust air by the exhaust filter device for nuclear power facilities as a whole, and can meet the use requirements, and the second pre-filter 43 and the second air filter 44 can also be increased or decreased according to actual conditions. When the first pre-filter 31, the first air filter 32, the electric heater 41, and the iodine adsorber 42 are arranged in the same box shell in sequence and share the outer wall 100 of the box shell, the first valve 7 is located in the box shell at this time, and the first valve 7 can use an electric isolation valve to achieve remote control outside the box shell. In this embodiment, the specific use process is as follows: when the exhaust air contains the predetermined substance, the first valve 7, the third valve 9 and the fourth valve 10 are opened, and the second valve 8 is closed, so that the exhaust air passes through the air inlet pipe 1, the first pre-filter 31, the first air filter 32, the electric heater 41, the iodine adsorber 42, and the air outlet pipe 2 in sequence for exhaust filtration, which can remove conventional pollutants and predetermined substances in the exhaust air; when the exhaust air does not contain the predetermined substance, the second valve 8, the third valve 9 and the fourth valve 10 are opened, and the first valve 7 is closed, so that the exhaust air passes through the air inlet pipe 1, the first pre-filter 31, the first air filter 32, the transition pipe 5 and the air outlet pipe 2 in sequence for exhaust filtration, which can remove conventional pollutants and predetermined substances in the exhaust air.

[0053] In summary, the present invention effectively overcomes some practical problems in the prior art and thus has high utilization value and use significance.

[0054] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. An exhaust filter device for a nuclear power facility, characterized in that: include: Air inlet pipe; Air outlet pipe; Universal filtration system for filtering delivered gas; A dedicated filtering system for filtering at least a predetermined substance in the delivered gas; the dedicated filtering system and the universal filtering system are connected to form a whole, one end of the whole is connected to the air inlet pipe, and the other end is connected to the air outlet pipe; A transition pipe is arranged in parallel with the dedicated filtering system, and one end of the transition pipe is connected to one end of the universal filtering system, and the other end is connected to the air inlet pipe or the air outlet pipe; an exhaust fan, arranged at one end of the universal filtering system; A first valve, disposed at the air inlet end of the dedicated filtration system; A second valve is disposed on the transition pipe; The third valve is arranged on the air outlet pipe.

2. The exhaust filter device for nuclear power facilities according to claim 1, characterized in that: The universal filtering system includes a first pre-filter and a first air filter which are sequentially arranged in series.

3. The exhaust filter device for nuclear power facilities according to claim 1, characterized in that: The dedicated filtering system at least comprises an electric heater and an iodine adsorber which are sequentially arranged in series.

4. The exhaust filter device for nuclear power facilities according to claim 3, characterized in that: The dedicated filtering system also includes a second filter and a second air filter which are sequentially arranged in series.

5. The exhaust filter device for nuclear power facilities according to claim 1, characterized in that: The universal filtering system and the special filtering system are arranged in one piece.

6. The exhaust air filter device for nuclear power facilities according to claim 4, characterized in that: The electric heater is arranged downstream of the second air filter.

7. The exhaust air filter device for nuclear power facilities according to claim 1, characterized in that: It also includes an exhaust fan, which is arranged upstream of the third valve near the air outlet pipe.

8. The exhaust filter device for nuclear power facilities according to claim 7, characterized in that: The exhaust fan is a variable frequency fan.

9. The exhaust air filter device for nuclear power facilities according to claim 6, characterized in that: The air inlet pipe, the second filter, the second air filter, the electric heater, the iodine adsorber, the first pre-filter and the first air filter are arranged in series in sequence, one end of the transition pipe is connected to the air inlet pipe, and the other end is connected to between the iodine adsorber and the first pre-filter.

10. The exhaust air filter device for nuclear power facilities according to claim 1, characterized in that: At least one of the first valve, the second valve and the third valve is an electric isolation valve.

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