A nuclear power plant hydrogen-containing exhaust gas composite treatment system and a method of using the same

Abstract

The application discloses a hydrogen-containing waste gas composite treatment system for a nuclear power plant, which comprises a hydrogen-containing waste gas pretreatment assembly, a front hydrogen-oxygen measuring unit, a gas heater, a hydrogen-oxygen composite device, a gas cooler and a rear hydrogen-oxygen measuring unit. The hydrogen-containing waste gas pretreatment assembly comprises a main pipeline, an oxygen injection circuit, a nitrogen injection circuit and a gas mixing tank. The main pipeline is communicated with the gas mixing tank and is a hydrogen-containing waste gas pipeline. The hydrogen-containing waste gas is input into the gas mixing tank. The gas mixing tank is communicated with the oxygen injection circuit and the nitrogen injection circuit, and the hydrogen-containing waste gas in the gas mixing tank is pretreated. The outlet of the gas mixing tank is communicated with the inlet of the gas heater. The gas heater is communicated with the gas mixing tank and the hydrogen-oxygen composite device. The hydrogen-oxygen composite device is internally provided with a hydrogen-oxygen composite catalyst. In general, the application has the advantages of high gas mixing stability, high heat energy utilization efficiency, high operation safety, and good continuous operation reliability.

Description

Technical Field

[0001] This invention belongs to the field of nuclear power plant hydrogen-containing waste gas treatment technology, specifically relating to a composite treatment system for nuclear power plant hydrogen-containing waste gas and its usage method. Background Technology

[0002] With the continuous development of industrial manufacturing, energy utilization, and scientific research, gas mixing, regulation, and heat treatment technologies are widely used in chemical production, energy testing, materials processing, environmental simulation, and testing equipment. The controlled mixing of multiple gases, along with precise control of their temperature, pressure, and flow rate, is a key technological foundation for ensuring the stability of related processes and the reliability of experimental data. Meanwhile, with the operation of nuclear power plants, the radioactive waste gas produced by the reactor contains hydrogen. This is not only because hydrogen is added to the nuclear reactor as part of the coolant, but also because changes in equipment operating temperature and pressure cause the generated hydrogen and radionuclides to diffuse into related equipment along with the coolant flow. Especially when the hydrogen concentration exceeds 4% by volume, hydrogen may pose a risk of combustion and explosion; therefore, the control of hydrogen is particularly important.

[0003] Existing nuclear power plant exhaust gas treatment technologies mainly treat these exhaust gases through processes such as pressurized storage in decay tanks and activated carbon retention decay. However, these processes do not effectively reduce the hydrogen concentration before treatment. If oxygen concentration monitoring fails, system control problems occur, or decay tank leaks occur, there is still a safety hazard of hydrogen-oxygen explosion. In addition, in order to reduce the potential risk of "hydrogen explosion", existing technologies require strict control of oxygen concentration and complex fire protection zoning and equipment selection requirements in system design. This not only increases construction costs but may also increase environmental hazards, especially in terms of the emission of radioactive gases.

[0004] There is an urgent need to propose a composite treatment system for hydrogen-containing waste gas from nuclear power plants and its application method, which can effectively reduce hydrogen concentration, avoid the safety risks of hydrogen accumulation, improve heat recovery efficiency, reduce energy consumption, and solve existing problems such as insufficient hydrogen concentration control, high energy consumption, low heat utilization efficiency, insufficient system stability and safety, and significant environmental hazards. Summary of the Invention

[0005] In view of this, the present invention proposes a composite treatment system for hydrogen-containing waste gas from nuclear power plants and its application method, which is applied to the field of hydrogen-containing waste gas treatment technology in nuclear power plants, and solves the existing technical problems of insufficient hydrogen concentration control, high energy consumption, low thermal energy utilization efficiency, insufficient system stability and safety, and significant environmental hazards.

[0006] To achieve the above-mentioned technical objectives, the specific technical solution adopted by the present invention is as follows: A hydrogen-containing waste gas composite treatment system for nuclear power plants includes a hydrogen-containing waste gas pretreatment component, a pre-hydrogen and oxygen measurement unit, a gas heater, a hydrogen-oxygen recombiner, a gas cooler, and a post-hydrogen and oxygen measurement unit. The hydrogen-containing waste gas pretreatment component is located at the inlet side of the system and includes a main pipeline, an oxygen injection circuit, a nitrogen injection circuit, and a gas mixing tank. The main pipeline is connected to the gas mixing tank and is a hydrogen-containing waste gas pipeline that introduces the hydrogen-containing waste gas into the gas mixing tank. The gas mixing tank is connected to the oxygen injection circuit and the nitrogen injection circuit, and the hydrogen-containing waste gas is introduced into the gas mixing tank through the oxygen injection circuit. The gas mixing tank is pretreated by a nitrogen injection circuit. The outlet of the gas mixing tank is connected to the inlet of the gas heater. The gas heater is connected to both the gas mixing tank and the hydrogen-oxygen combiner. The hydrogen-oxygen combiner is equipped with a hydrogen-oxygen combiner catalyst. Gas delivery pipelines are installed between the hydrogen-containing waste gas pretreatment component and the gas mixing tank, between the gas mixing tank and the gas heater, between the gas heater and the hydrogen-oxygen combiner, and at the outlet of the hydrogen-oxygen combiner. A temperature sensor is installed on the gas delivery pipeline in front of the rear hydrogen-oxygen measurement unit.

[0007] Furthermore, the pre-hydrogen-oxygen measurement unit is installed on the gas delivery pipeline between the gas mixing tank and the gas heater, and the post-hydrogen-oxygen measurement unit is installed at the rear end of the gas cooler. Both ends of the pre-hydrogen-oxygen measurement unit and the post-hydrogen-oxygen measurement unit are connected to the gas delivery pipeline through flame arresters.

[0008] Furthermore, the pre-hydrogen and oxygen measurement unit includes a first gas dryer, a first diaphragm compressor, and a first hydrogen and oxygen measurement cabinet arranged sequentially from front to back, and the post-hydrogen and oxygen measurement unit includes a second gas dryer, a second diaphragm compressor, and a second hydrogen and oxygen measurement cabinet arranged sequentially from front to back.

[0009] Furthermore, both the oxygen injection circuit and the nitrogen injection circuit are equipped with gas filters, each containing a stainless steel wire mesh filter basket. A gas regulating valve is located at the front end of the gas mixing tank, on the corresponding oxygen injection circuit and nitrogen injection circuit, respectively.

[0010] Furthermore, a heating filter is installed at the outlet of the gas heater to filter dust particles from the gas discharged from the gas heater, and a demister is installed in the gas cooler and the post-hydrogen and oxygen measurement unit.

[0011] Furthermore, a flame arrester is also installed between the heating filter and the gas heater. The outlet of the hydrogen-oxygen combiner and the inlet of the gas cooler are both connected to the gas heater through the installed gas delivery pipeline, thereby forming a heating path between the hydrogen-oxygen combiner and the gas heater.

[0012] Furthermore, a flame arrester is installed on the gas delivery pipeline between the outlet of the hydrogen-oxygen recombiner and the gas heater. The flame arrester includes a porous metal core and a flame arrester shell.

[0013] A method for using the hydrogen-containing waste gas composite treatment system of a nuclear power plant as described above includes the following steps: S1. Hydrogen-containing waste gas is input through the main pipeline, and oxygen is filtered, pressure regulated and flow regulated through the oxygen injection circuit. Nitrogen is filtered, pressure regulated and flow regulated through the nitrogen injection circuit. S2. Mix hydrogen-containing waste gas, oxygen, and nitrogen inside a gas mixing tank; S3. The mixed gas is fed into the gas heater for preheating. S4. The preheated gas is sent into the hydrogen-oxygen recombination device to carry out the hydrogen-oxygen recombination reaction. S5. The combined gas is processed sequentially through a gas cooler and a demister. During the detection process, the gas entering the gas heater and the gas discharged from the hydrogen-oxygen combiner are processed and monitored by the pre-hydrogen and post-hydrogen measurement units, respectively.

[0014] By adopting the above technical solution, the present invention can also bring the following beneficial effects: 1. This invention proposes a composite treatment system for hydrogen-containing waste gas in nuclear power plants and its usage method. By precisely controlling the mixing ratio of hydrogen, oxygen, and nitrogen, and combining gas filtration, pressure regulation, and flow regulation structures, stable gas supply and precise control are achieved. This ensures that the waste gas maintains a stable pressure and flow rate before entering the mixing stage. Through the function of the gas mixing tank, the uniformity and consistency of the mixed gas are effectively guaranteed, thereby avoiding the problems of large fluctuations in gas ratio and uneven mixing in existing systems. This invention has the advantages of improving gas mixing stability and basic system operational reliability.

[0015] 2. This invention proposes a composite treatment system for hydrogen-containing waste gas in nuclear power plants and its usage method. By setting up a gas heater and a hydrogen-oxygen compositer to work together, the gas heater is used to rapidly raise the temperature during the system startup phase. By setting up a multi-stage gas filtration structure, the gas after the high-temperature reaction is kept stable at an appropriate temperature and humidity, avoiding the problems of high energy consumption and large heat waste in the prior art. It has the advantages of reducing energy consumption, improving thermal energy utilization efficiency and system operating efficiency.

[0016] 3. This invention proposes a composite treatment system for hydrogen-containing waste gas in nuclear power plants and its usage method. By setting up temperature sensors, pre-hydrogen and post-hydrogen and oxygen measurement units, the system monitors the temperature, pressure, and flow parameters of the gas in real time. Combined with the collaborative protection design of flame arresters, the system's safety protection capability under abnormal operating conditions is improved, ensuring that the system can maintain stability and safety during startup, operation, and shutdown. This avoids the problems of monitoring lag and insufficient safety redundancy in existing systems, and has the advantages of improving system safety and operational stability. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 The present invention provides a structural diagram of a composite treatment system for hydrogen-containing waste gas from a nuclear power plant; The components include: 1. Hydrogen-containing waste gas treatment assembly; 2. Pre-hydrogen and oxygen measurement unit; 3. Gas heater; 4. Hydrogen-oxygen recombination unit; 5. Gas cooler; 6. Post-hydrogen and oxygen measurement unit; 7. Gas pipeline; 8. Flame arrester; 9. Filter; 10. Demister; 11. Main pipeline; 12. Oxygen injection branch; 13. Nitrogen injection branch; 14. Gas mixing tank; 15. Gas filter; 21. First gas dryer; 22. First diaphragm compressor; 23. First hydrogen and oxygen measurement cabinet; 41. Hydrogen and oxygen recombination catalyst; 61. Second gas dryer; 62. Second diaphragm compressor; 63. Second hydrogen and oxygen measurement cabinet. Detailed Implementation

[0019] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0020] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. 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 based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this invention, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using other structures and / or functionalities besides one or more of the aspects set forth herein.

[0022] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0023] Furthermore, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the aspects described can be practiced without these specific details. Example 1

[0024] like Figure 1 As shown, a hydrogen-containing waste gas composite treatment system for nuclear power plants includes a hydrogen-containing waste gas pretreatment component 1, a pre-hydrogen and oxygen measurement unit 2, a gas heater 3, a hydrogen and oxygen combiner 4, a gas cooler 5, and a post-hydrogen and oxygen measurement unit 6. The hydrogen-containing waste gas pretreatment component 1 is located at the inlet side of the system. The hydrogen-containing waste gas pretreatment component 1 includes a main pipeline 11, an independently configured oxygen injection circuit 12, a nitrogen injection circuit 13, and a gas mixing tank 14. The main pipeline 11 is connected to the gas mixing tank 14 and is a hydrogen-containing waste gas pipeline that inputs the hydrogen-containing waste gas into the gas mixing tank 14. The gas mixing tank 14 is also connected to the oxygen injection circuit 12 and the nitrogen injection circuit 13. The hydrogen-containing waste gas inside the gas mixing tank 14 is pretreated through the oxygen injection circuit 12 and the nitrogen injection circuit 13. The outlet of the gas mixing tank 22 is connected to the inlet of the gas heater 3. The gas heater 3 is connected to the gas mixing tank 22 and the hydrogen-oxygen combiner 4 respectively. The hydrogen-oxygen combiner 4 is equipped with a hydrogen-oxygen combiner catalyst. Gas delivery pipelines 7 are provided between the hydrogen-containing waste gas pretreatment component 1 and the gas mixing tank 14, between the gas mixing tank 14 and the gas heater 3, between the gas heater 3 and the hydrogen-oxygen combiner 4, and at the outlet of the hydrogen-oxygen combiner 44. A temperature sensor is provided on the gas delivery pipeline 7 on the front side of the rear hydrogen-oxygen measurement unit 6.

[0025] The pre-hydrogen-oxygen measurement unit 2 is installed on the gas delivery pipeline 7 between the gas mixing tank 14 and the gas heater 3, and the post-hydrogen-oxygen measurement unit 6 is installed at the rear end of the gas cooler 5. Both ends of the pre-hydrogen-oxygen measurement unit 2 and the post-hydrogen-oxygen measurement unit 6 are connected to the gas delivery pipeline 7 through flame arresters 8. The pre-hydrogen-oxygen measurement unit 2 includes a first gas dryer 21, a first diaphragm compressor 22 and a first hydrogen-oxygen measurement cabinet 23 arranged sequentially from front to back. The post-hydrogen-oxygen measurement unit 6 includes a second gas dryer 61, a second diaphragm compressor 62 and a second hydrogen-oxygen measurement cabinet 63 arranged sequentially from front to back.

[0026] Both the oxygen injection circuit 12 and the nitrogen injection circuit 13 are equipped with gas filters 15, and the gas filters 15 are equipped with stainless steel wire mesh filter baskets. The front end of the gas mixing tank 14 is equipped with a gas regulating valve, which is located on the corresponding oxygen injection circuit 12 and nitrogen injection circuit 13 respectively.

[0027] A heating filter 9 is installed at the outlet of the gas heater 3 to filter dust particles from the gas discharged from the gas heater 3. A demister 10 is installed in the gas cooler 5 and the post-hydrogen-oxygen measurement unit 6. A flame arrester 8 is also installed between the heating filter 9 and the gas heater 3. The outlet of the hydrogen-oxygen combiner 4 and the inlet of the gas cooler 5 are both connected to the gas heater 3 through a gas delivery pipeline 7, thereby forming a heating path between the hydrogen-oxygen combiner 4 and the gas heater 3. A flame arrester 8 is also installed on the gas delivery pipeline 7 between the outlet of the hydrogen-oxygen combiner 4 and the gas heater 3. The flame arrester 8 includes a porous metal core and a flame arrestor shell.

[0028] This system can be applied to industrial hydrogen-containing tail gas treatment, hydrogen energy experimental systems, chemical gas treatment systems, and hydrogen-containing gas treatment systems inside the containment of nuclear power plants, and can significantly improve the treatment efficiency of hydrogen-oxygen mixed gases.

[0029] A method for using a composite treatment system for hydrogen-containing waste gas from a nuclear power plant includes the following steps: S1. Hydrogen-containing waste gas is input through the main pipeline 11, and oxygen is filtered, pressure regulated and flow regulated through the oxygen injection circuit 12. Nitrogen is filtered, pressure regulated and flow regulated through the nitrogen injection circuit 13. S2. Mix hydrogen-containing waste gas, oxygen and nitrogen inside the gas mixing tank 14; S3. The mixed gas is fed into the gas heater 3 for preheating. S4. The preheated gas is sent into the hydrogen-oxygen recombination device 4 to carry out the hydrogen-oxygen recombination reaction. S5. The combined gas is processed sequentially through the gas cooler 5 and the demister 10. During the detection process, the gas entering the gas heater 3 and the gas discharged from the hydrogen-oxygen combiner 4 are processed and monitored by the pre-hydrogen-oxygen measurement unit 2 and the post-hydrogen-oxygen measurement unit 6, respectively.

[0030] By implementing the above methods and steps, hydrogen-containing waste gas, oxygen, and nitrogen are mixed in a stable ratio to form a mixed gas inside the gas mixing tank 14. The mixed gas is preheated and then enters the hydrogen-oxygen composite reactor 4 to complete the hydrogen-oxygen composite reaction. After cooling, drying, and staged compression, a stable output gas is formed. In summary, the present invention has the advantages of high gas mixing stability, high thermal energy utilization efficiency, strong operational safety, and good continuous operation reliability.

[0031] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A composite treatment system for hydrogen-containing waste gas from a nuclear power plant, characterized in that: The system includes a hydrogen-containing waste gas pretreatment component, a pre-hydrogen-oxygen measurement unit, a gas heater, a hydrogen-oxygen recombiner, a gas cooler, and a post-hydrogen-oxygen measurement unit. The hydrogen-containing waste gas pretreatment component is located at the system inlet. It includes a main pipeline, an oxygen injection circuit, a nitrogen injection circuit, and a gas mixing tank. The main pipeline, which is connected to the gas mixing tank, is a hydrogen-containing waste gas pipeline that introduces the waste gas into the gas mixing tank. The gas mixing tank is connected to both the oxygen and nitrogen injection circuits, which pre-treat the hydrogen-containing waste gas inside. The outlet of the gas mixing tank is connected to the inlet of the gas heater. The gas heater is connected to both the gas mixing tank and the hydrogen-oxygen recombiner. The hydrogen-oxygen recombiner contains a hydrogen-oxygen recombining catalyst. Gas delivery pipelines are installed between the hydrogen-containing waste gas pretreatment component and the gas mixing tank, between the gas mixing tank and the gas heater, between the gas heater and the hydrogen-oxygen recombiner, and at the outlet of the hydrogen-oxygen recombiner. A temperature sensor is located on the gas delivery pipeline in front of the post-hydrogen-oxygen measurement unit.

2. The composite treatment system for hydrogen-containing waste gas from a nuclear power plant according to claim 1, characterized in that: The pre-hydrogen-oxygen measurement unit is installed on the gas delivery pipeline between the gas mixing tank and the gas heater, and the post-hydrogen-oxygen measurement unit is installed at the rear end of the gas cooler. Both ends of the pre-hydrogen-oxygen measurement unit and the post-hydrogen-oxygen measurement unit are connected to the gas delivery pipeline through flame arresters.

3. The composite treatment system for hydrogen-containing waste gas from a nuclear power plant according to claim 2, characterized in that: The pre-hydrogen and oxygen measurement unit includes a first gas dryer, a first diaphragm compressor, and a first hydrogen and oxygen measurement cabinet arranged sequentially from front to back. The post-hydrogen and oxygen measurement unit includes a second gas dryer, a second diaphragm compressor, and a second hydrogen and oxygen measurement cabinet arranged sequentially from front to back.

4. The composite treatment system for hydrogen-containing waste gas from a nuclear power plant according to claim 3, characterized in that: Both the oxygen injection circuit and the nitrogen injection circuit are equipped with gas filters, each containing a stainless steel wire mesh filter basket. The front end of the gas mixing tank is equipped with a gas regulating valve, located on the corresponding oxygen injection circuit and nitrogen injection circuit, respectively.

5. A composite treatment system for hydrogen-containing waste gas from a nuclear power plant according to claim 4, characterized in that: A heating filter is installed at the outlet of the gas heater to filter dust particles from the gas discharged from the gas heater. A demister is installed in the gas cooler and the post-hydrogen and oxygen measurement unit.

6. The composite treatment system for hydrogen-containing waste gas from a nuclear power plant according to claim 5, characterized in that: A flame arrester is also installed between the heating filter and the gas heater. The outlet of the hydrogen-oxygen combiner and the inlet of the gas cooler are both connected to the gas heater through the gas delivery pipeline, thereby forming a heating path between the hydrogen-oxygen combiner and the gas heater.

7. A composite treatment system for hydrogen-containing waste gas from a nuclear power plant according to claim 6, characterized in that: A flame arrester is installed on the gas delivery pipeline between the outlet of the hydrogen-oxygen recombiner and the gas heater. The flame arrester includes a porous metal core and a flame arrester shell.

8. A method of using the nuclear power plant hydrogen-containing waste gas composite treatment system according to claim 7, characterized in that, The steps include the following: S1. Hydrogen-containing waste gas is input through the main pipeline, and oxygen is filtered, pressure regulated and flow regulated through the oxygen injection circuit. Nitrogen is filtered, pressure regulated and flow regulated through the nitrogen injection circuit. S2. Mix hydrogen-containing waste gas, oxygen, and nitrogen inside a gas mixing tank; S3. The mixed gas is fed into the gas heater for preheating. S4. The preheated gas is sent into the hydrogen-oxygen recombination device to carry out the hydrogen-oxygen recombination reaction. S5. The combined gas is processed sequentially through a gas cooler and a demister. During the detection process, the gas entering the gas heater and the gas discharged from the hydrogen-oxygen combiner are processed and monitored by the pre-hydrogen and post-hydrogen measurement units, respectively.

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