Radioactive hydrogen-containing tail gas treatment system

Abstract

The application relates to a radioactive hydrogen-containing tail gas treatment system, which comprises a tail gas flow pipeline and a cooling water pipeline for providing cooling water to a condensing device; the tail gas flow pipeline comprises a condensing module, a combustion module for combusting hydrogen and a washing module for washing radioactive pollutants and residual hydrogen fluoride; the condensing module comprises at least one gas-water separator and at least one condensing device for condensing hydrogen fluoride; the gas-water separator is arranged downstream of the condensing device; the washing module is communicated with a gas path outlet of the gas-water separator and is arranged upstream of the combustion module; and the condensing device is further communicated with the cooling water pipeline. The application can efficiently remove hydrogen fluoride, hydrogen and radioactive pollutants in radioactive acidic tail gas.

Description

Technical Field

[0001] This application relates to the field of radioactive waste treatment technology, and more specifically, to a radioactive hydrogen-containing tail gas treatment system. Background Technology

[0002] Nuclear power plants and nuclear fuel cycle facilities generate a certain amount of radioactive hydrogen-containing waste gas during normal operation. The hydrogen in the waste gas of nuclear power plants mainly comes from reactor coolant and related containers, including hydrogen generated by primary loop irradiation, hydrogen dissolved in the charge flow provided by chemical volume and control systems, and hydrogen covered by the containment control box, which brings about hydrogen safety and radioactive release issues.

[0003] During nuclear fuel processing, such as the preparation of uranium dioxide (UO2), radioactive hydrogen-containing acidic exhaust gases are also generated. The main manufacturing processes for uranium dioxide powder include ADU (ammonium diuranate), AUC (ammonium tricarbonate), and IDR (integrated dry process). Among these, the ADU and AUC methods are wet processes for preparing uranium dioxide powder. Wet processes have relatively long flows, generate large amounts of wastewater and waste residue, and the complex composition of ADU results in poor reproducibility of the generated UO2 powder with a high fluorine (F) content, which negatively impacts pellet manufacturing. The IDR method is a dry process for preparing uranium dioxide powder, mainly involving the gasification, hydrolysis, and defluorination reduction of UF6. Specifically, gaseous UF6 reacts with water vapor in the reactor to generate uranyl fluoride, which is further reduced to UO2 by hydrogen. This method has advantages such as a short process flow, high production capacity, simple equipment structure, and minimal waste liquid. However, the hydrolysis and hydrogen reduction of uranium hexafluoride will produce high concentrations of HF gas, along with excess hydrogen gas, and may also contain uranium-containing compounds such as uranyl fluoride and uranium hexafluoride.

[0004] Therefore, the high concentrations of hydrogen (H2), hydrogen fluoride (HF), and radioactive pollutants (such as uranyl fluoride and uranium hexafluoride and other uranium-containing compounds) contained in radioactive acidic exhaust gases are highly corrosive, flammable and explosive, high-temperature, and radioactive. If they cannot be efficiently removed, the substandard exhaust gases will pose significant safety hazards and affect the safety of the system and the workers. Utility Model Content

[0005] The technical problem to be solved by this application is to provide a radioactive hydrogen-containing tail gas treatment system, which addresses the above-mentioned deficiencies of the prior art.

[0006] The technical solution adopted by this application to solve its technical problem is: constructing a radioactive hydrogen-containing tail gas treatment system, including:

[0007] Exhaust gas circulation pipeline, including:

[0008] A condensation module includes at least one gas-liquid separator and at least one condensation device for condensing hydrogen fluoride; the gas-liquid separator is located downstream of the condensation device.

[0009] A combustion module for burning hydrogen; and

[0010] A washing module for washing away radioactive contaminants and residual hydrogen fluoride, the washing module being connected to the gas outlet of the gas-water separator and positioned upstream of the combustion module; and

[0011] A cooling water pipeline provides cooling water to the condensing equipment, and the condensing equipment is also connected to the cooling water pipeline.

[0012] In some embodiments, the condensation device includes at least one precooler and at least one condenser, the at least one condenser being disposed between the at least one precooler and the at least one gas-water separator.

[0013] In some embodiments, the condensing device includes a precooler and at least two condensers; the condensing module includes at least two gas-liquid separators; the at least two condensers are arranged in parallel downstream of the precooler, and the at least two gas-liquid separators are respectively arranged downstream of the at least two condensers.

[0014] In some embodiments, the cooling water pipeline includes a cooling water return pipeline and a cooling water inlet pipeline for supplying cooling water to the at least one condenser; the inlet end of the at least one condenser is connected to the cooling water inlet pipeline, and the outlet end is connected to the cooling water return pipeline; the precooler is connected to the cooling water return pipeline.

[0015] In some embodiments, the cooling water pipeline further includes at least one return water bypass; one end of the at least one return water bypass is connected to the outlet end of the at least one condenser, and the other end is connected to the cooling water inlet pipeline downstream of the precooler; at least one valve for regulating the flow rate is provided on the return water bypass.

[0016] In some embodiments, a temperature instrument and a flow meter are respectively provided at the inlet and outlet ends of the at least one condenser;

[0017] And / or, the at least one gas-liquid separator is provided with a temperature probe for detecting the temperature of the condensate.

[0018] In some embodiments, the precooler is a shell-and-tube heat exchanger; and / or

[0019] The at least one condenser is a graphite condenser.

[0020] In some embodiments, the washing module includes a Venturi device and a washing apparatus containing washing liquid; the Venturi device is disposed between the at least one gas-liquid separator and the washing apparatus.

[0021] In some embodiments, the chamber within the washing device is divided into a gas chamber and a liquid chamber by the washing liquid; the outlet end of the Venturi device extends into the liquid chamber, and the combustion module is connected to the outlet end of the washing device corresponding to the gas chamber.

[0022] In some embodiments, a circulation pipeline for circulating the washing liquid within the washing module is further included. The circulation pipeline includes a circulation line and at least one circulation pump disposed on the circulation line. One end of the circulation line is connected to the inlet end of the Venturi device, and the other end is connected to the outlet end of the washing device corresponding to the liquid chamber.

[0023] In some embodiments, the number of circulation pumps is at least two, and the at least two circulation pumps are arranged in parallel on the circulation pipeline.

[0024] In some embodiments, the circulation pipeline further includes a diversion pipeline, one end of which is connected to the circulation pipeline and the other end of which is connected to the inlet of the washing device.

[0025] In some embodiments, an anti-corrosion layer is provided on the inner wall of the at least one gas-water separator; and / or

[0026] The inner wall of the washing device is provided with an anti-corrosion layer.

[0027] In some embodiments, it also includes:

[0028] A recovery pipeline for recovering hydrogen fluoride condensate is connected downstream of the liquid outlet of the gas-liquid separator; and / or

[0029] Wastewater treatment pipelines for collecting radioactive contaminants and residual hydrogen fluoride are located downstream of the washing module.

[0030] In some embodiments, the combustion module includes a flameless combustion device.

[0031] Implementing the technical solution constructed in this application has at least the following beneficial effects:

[0032] This application, by sequentially installing a condensation module, a scrubbing module, and a combustion module in the exhaust gas flow pipeline, allows for the removal of most of the hydrogen fluoride from the exhaust gas via the condensation module. Then, by placing the scrubbing module downstream of the condensation module, the inherent properties of hydrogen fluoride are utilized to further remove residual hydrogen fluoride from the exhaust gas while simultaneously removing radioactive materials. This achieves purification of both radioactive pollutants and residual hydrogen fluoride in the exhaust gas, thereby improving the effectiveness of exhaust gas purification. Finally, by placing the combustion module downstream of the scrubbing module, the remaining hydrogen in the exhaust gas is efficiently removed, ultimately achieving compliant emissions. Attached Figure Description

[0033] The present application will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0034] Figure 1 This is a schematic diagram of the structure of a radioactive hydrogen-containing tail gas treatment system in one embodiment of this application. Detailed Implementation

[0035] To provide a clearer understanding of the technical features, objectives, and effects of this application, the specific embodiments of this application are now described in detail with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0036] In the description of this application, it should be understood that the terms "longitudinal", "lateral", "up", "down", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0038] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0039] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0040] Figure 1 The present application illustrates a radioactive hydrogen-containing tail gas treatment system 1, which can remove substances such as hydrogen (H2), hydrogen fluoride (HF), and radioactive contaminants (such as uranium-containing compounds) from radioactive acidic tail gas to achieve safe discharge of the tail gas.

[0041] The radioactive hydrogen-containing exhaust gas treatment system 1 includes an exhaust gas flow pipeline 10, a recovery pipeline 20, a waste liquid treatment pipeline 30, a cooling water pipeline 40, and a circulation pipeline 50. The exhaust gas flow pipeline 10 includes an exhaust gas flow path 14 for circulating the exhaust gas. A condensation module, a scrubbing module, and a combustion module are sequentially arranged along the exhaust gas flow direction on the exhaust gas flow path 14. The condensation module removes most of the hydrogen fluoride from the exhaust gas. The scrubbing module removes radioactive materials and residual hydrogen fluoride. The combustion module removes hydrogen from the exhaust gas through combustion.

[0042] The recovery pipeline 20 is located downstream of the condensation module and is used to recover the condensate obtained from the condensation module. The condensate contains a large amount of hydrogen fluoride removed from the exhaust gas. The waste liquid treatment pipeline 30 is located downstream of the washing module and is used to collect the waste liquid generated from the washing exhaust gas of the washing module. The waste liquid contains radioactive substances removed from the exhaust gas and residual hydrogen fluoride.

[0043] The cooling water pipeline 40 is connected to the condensation module and supplies cooling water to the condensation module to achieve the condensation and removal of hydrogen fluoride in the exhaust gas through heat exchange between the cooling water and the exhaust gas. The circulation pipeline 50 is connected to the washing module and is used to realize the recycling of washing liquid in the washing module.

[0044] It is important to understand that the radioactive acidic exhaust gas contains high concentrations of hydrogen (H2), hydrogen fluoride (HF), and radioactive contaminants (such as uranyl fluoride and uranium hexafluoride and other uranium-containing compounds). These substances are highly corrosive, flammable, explosive, hot, and radioactive. If they cannot be efficiently removed, the substandard exhaust gas will pose a significant safety hazard, affecting the safety of the system and the workers.

[0045] This application, by sequentially installing a condensation module, a scrubbing module, and a combustion module on the exhaust gas flow pipeline 14, allows for the removal of most of the hydrogen fluoride from the exhaust gas via the condensation module, and the recycling pipeline 20 enables the recovery and reuse of high-concentration hydrogen fluoride condensate. By placing the scrubbing module downstream of the condensation module, the inherent properties of hydrogen fluoride are utilized to further remove residual hydrogen fluoride from the exhaust gas while removing radioactive materials, thus achieving purification of both radioactive pollutants and residual hydrogen fluoride and improving the overall exhaust gas purification effect. Finally, by placing the combustion module downstream of the scrubbing module, the remaining hydrogen in the exhaust gas is efficiently removed, ultimately achieving compliant emissions.

[0046] In some embodiments, the condensation module includes at least one condensation device and at least one gas-liquid separator 113. The condensation device is used to reduce the exhaust gas temperature to condense and liquefy the hydrogen fluoride in the exhaust gas, thereby removing the hydrogen fluoride from the exhaust gas. The gas-liquid separator 113 is located downstream of the condensation device and is used to separate the liquefied hydrogen fluoride from the exhaust gas phase.

[0047] Specifically, the condenser and the gas-liquid separator 113 are both installed on the exhaust gas flow pipeline 14. The inlet end of the condenser is connected to the front-end system (such as a reactor) of the exhaust gas, and the outlet end is connected to the inlet end of the gas-liquid separator 113. The condenser is also connected to the cooling water pipeline 40 so that the cooling water pipeline 40 can supply cooling water to the condenser, allowing the cooling water to exchange heat with the high-temperature exhaust gas to reduce the exhaust gas temperature and achieve the condensation of hydrogen fluoride.

[0048] The gas-liquid separator 113 separates the mixture of condensate and tail gas discharged from its inlet end into a gas-liquid mixture. Its outlet end includes a gas outlet for discharging gas and a liquid outlet for discharging condensate. The inlet end of the washing module is connected to the gas outlet of the gas-liquid separator 113 to further remove most of the hydrogen fluoride from the tail gas. The inlet end of the recovery pipeline 20 is connected to the liquid outlet of the gas-liquid separator 113 to recover condensate containing a high concentration of hydrogen fluoride.

[0049] Furthermore, the condensation device may include a precooler 111 and at least one condenser 112. The precooler 111 is used to initially cool the high-temperature exhaust gas. The condenser 112 is disposed between the precooler 111 and the gas-liquid separator 113 and is used to further cool the initially cooled exhaust gas to condense hydrogen fluoride.

[0050] It's important to understand that related technologies for removing hydrogen fluoride from exhaust gases include adsorption, absorption, and condensation methods. Adsorption is primarily used in the initial treatment stage of hydrogen fluoride removal, but its removal rate is insufficient. Absorption converts hydrogen fluoride into easily treatable compounds through chemical reactions, but these compounds still require further processing, making the process relatively complex. Condensation methods typically use a single condenser to condense the exhaust gas, which places high demands on the condenser equipment and operator control, resulting in lower economic efficiency.

[0051] This application achieves efficient condensation and removal of hydrogen fluoride by setting up condensation equipment including a precooler 111 and a condenser 112, and solves the problem of high requirements for single condensation equipment. The process is simple and economical.

[0052] In some other embodiments, the condensation device may also include only a single condenser.

[0053] In some embodiments, the number of precoolers 111 is one, and the number of condensers 112 and gas-liquid separators 113 is the same, with at least two. Each gas-liquid separator 113 is correspondingly disposed downstream of the condenser 112, forming a condensation branch. The outlet end of the precooler 111 can be connected to the inlet end of each condensation branch.

[0054] Thus, the configuration of at least two condensing branches allows for the backup of condenser 112 and gas-liquid separator 113. When condenser 112 and / or gas-liquid separator 113 on the operating condensing branch malfunctions, another normal condensing branch can be switched to operate at any time to ensure the normal and efficient operation of the radioactive hydrogen-containing tail gas treatment system 1.

[0055] In some other embodiments, the number of precoolers 111 may be the same as the number of condensers 112 and gas-water separators 113, and the three are connected in sequence to form a condensation branch. The condensation module may include one or at least two parallel condensation branches.

[0056] In some other embodiments, the number of gas-liquid separators 113 may be only one, and at least two condensers 112 may be connected in parallel between the precooler 111 and the gas-liquid separator 113.

[0057] In some other embodiments, the number of precoolers 111 may be the same as the number of condensers 112, and only one gas-liquid separator 113 may be provided. Each precooler 111 is connected to a condenser to form a condensation branch, and the gas-liquid separator 113 is located downstream of one or at least two condensation branches.

[0058] It should be noted that valves 60 can be installed between the precooler 111 and the condenser 112, between the condenser 112 and the gas-water separator 113, between the gas-water separator 113 and the washing module, and between the gas-water separator 113 and the recovery pipeline 20, so as to flexibly control the on / off state and flow rate of each pipeline.

[0059] In some embodiments, the condenser 112 employs an existing graphite condenser to utilize the graphite condenser's strong corrosion resistance, excellent thermal conductivity, and good chemical stability to achieve efficient heat exchange and condensation of the exhaust gas and hydrogen fluoride.

[0060] In some other embodiments, the condenser 112 may also employ other existing condenser types such as silicon carbide ceramic condensers.

[0061] In some embodiments, the precooler 111 may employ an existing coaxial heat exchanger.

[0062] Specifically, the shell-and-tube heat exchanger can be arranged horizontally, and the horizontal position of its outlet end can be lower than the horizontal position of its inlet end, so as to ensure that even if a small amount of condensate is generated in the precooler 111, it can flow out from the outlet end under the influence of gravity, so as to avoid backflow to the front end system.

[0063] In some other embodiments, the precooler 111 may also employ other heat exchanger types such as plate heat exchangers.

[0064] In some embodiments, the recovery line 20 may include a recovery pipeline, one end of which is connected to the liquid outlet of the gas-liquid separator 113, and the other end is connected to the hydrogen fluoride recovery system.

[0065] It should be noted that the hydrogen fluoride recovery system can be a system for recovering and treating hydrogen fluoride, or a system for reusing hydrogen fluoride condensate; no specific limitation is made here.

[0066] In some embodiments, the cooling water pipeline 40 may include a cooling water inlet pipeline 41 and a cooling water return pipeline 42. The outlet end of the cooling water inlet pipeline 41 and the inlet end of the cooling water return pipeline 42 are respectively connected to a condensing device. The cooling water inlet pipeline 41 is used to supply cooling water to the condensing device, so that the cooling water exchanges heat with the high-temperature exhaust gas within the condensing device, thereby achieving the condensation and removal of hydrogen fluoride in the exhaust gas. The cooling water return pipeline 42 is used to recover the water after the heat exchange.

[0067] Specifically, when the condensing equipment includes a precooler 111 and a condenser 112, the outlet end of the cooling water inlet pipe 41 is connected to the inlet end of the condenser 112, and the inlet end of the cooling water return pipe 42 is connected to the outlet end of the condenser 112. The precooler 111 is connected to the cooling water return pipe 42.

[0068] For example in Figure 1 In the embodiment shown, the outlet end of the cooling water inlet pipe 41 is connected to the inlet end of the two condensers 112 respectively, and the inlet end of the cooling water return pipe 42 is connected to the outlet end of the two condensers 112 respectively.

[0069] like Figure 1 As shown, when the radioactive hydrogen-containing exhaust gas treatment system 1 is operating normally, the high-temperature exhaust gas first enters the precooler 111 from the exhaust gas flow pipe 14, where it exchanges heat with the cooling water in the precooler 111, becoming a higher-temperature exhaust gas. The higher-temperature exhaust gas then enters the condenser 112 through the exhaust gas flow pipe 14, where it exchanges heat with the cooling water in the condenser 112, becoming a lower-temperature exhaust gas after hydrogen fluoride removal, and continues to enter the scrubbing module through the exhaust gas flow pipe 14.

[0070] Simultaneously, low-temperature cooling water enters the condenser 112 from the cooling water inlet pipe 41, where it exchanges heat with the higher-temperature exhaust gas inside the condenser 112, becoming lower-temperature cooling water. The lower-temperature cooling water then enters the precooler 111 through the cooling water return pipe 42, where it exchanges heat with the high-temperature exhaust gas inside the precooler 111, becoming non-low-temperature cooling water, and continues to flow out through the cooling water return pipe 42.

[0071] This avoids the condensation of hydrogen fluoride in the precooler 111 caused by the direct entry of low-temperature cooling water, thus reducing the corrosion risk of the precooler 111. It also improves the utilization rate of cooling water and reduces system operating costs.

[0072] Furthermore, the cooling water pipeline 40 may also include at least one return water bypass 43 for diverting the cooling water in the cooling water return pipeline 42. The two ends of the return water bypass 43 are respectively connected to the outlet end of the condenser 112 and the cooling water return pipeline 42 downstream of the precooler 111. At least one valve 60 is also provided on the return water bypass 43 for adjusting the cooling water flow rate of the return water bypass 43, thereby adjusting the cooling water flow rate entering the precooler 111.

[0073] This avoids excessively low outlet temperature of the precooler 111 due to excessive cooling water flow, thereby preventing large-scale condensation of hydrogen fluoride at this location and further reducing the risk of corrosion of the precooler 111.

[0074] It should be noted that the return water bypass 43 can share a section with the cooling water return pipe 42 to reduce pipe length and lower system cost.

[0075] In some other embodiments, when the condensation module includes at least two precoolers 111 and / or at least two condensers 112, the cooling water pipeline 40 may also be provided with at least two cooling water inlet pipelines 41, and / or at least two cooling water return pipelines 42, and / or at least two return water bypasses 43.

[0076] In some embodiments, the inlet and outlet ends of the condenser 112 are respectively equipped with temperature instruments and flow meters (not shown in the figure) to monitor the flow rate and cooling water temperature at the inlet end of the condenser 112 and the flow rate and cooling water temperature at the outlet end, thereby improving the control accuracy of operating parameters, ensuring that the outlet temperature of the condenser 112 meets the condensation requirements of hydrogen fluoride, and thus ensuring the condensation effect of hydrogen fluoride and improving the hydrogen fluoride recovery rate.

[0077] It should be noted that the inlet flow rate and cooling water temperature, and the outlet flow rate and cooling water temperature of the condenser 112 should be flexibly set according to factors such as the initial temperature of the cooling water, the initial temperature of the high-temperature exhaust gas, and the exhaust gas flow rate, and no specific limit is made here.

[0078] For example in Figure 1 In the embodiment shown, during the operation of the radioactive hydrogen-containing tail gas treatment system 1, data on factors such as the initial temperature of the cooling water, the initial temperature of the high-temperature tail gas, and the tail gas flow rate ensure that the temperature difference between the inlet and outlet of the condenser 112 is approximately 5°C.

[0079] In some embodiments, a temperature probe (not shown) is provided inside the gas-liquid separator 113 to detect the temperature of the condensate inside the gas-liquid separator 113. The installation of this temperature probe can be used to assess whether the performance of the precooler 111 and the condenser 112 is normal.

[0080] In some embodiments, the inner wall of the gas-water separator 113 is also provided with an anti-corrosion layer to prevent hydrogen fluoride from corroding the gas-water separator 113.

[0081] Specifically, the anti-corrosion layer can be made of polytetrafluoroethylene.

[0082] In other embodiments, the anti-corrosion layer may also be made of special fluoroplastics (such as soluble polytetrafluoroethylene PFA, perfluoroethylene propylene FEP, etc.), hydrofluoric acid resistant special coatings, acid resistant plastics (such as polyolefin PO, reinforced polypropylene FRPP, etc.), impermeable graphite, Monel alloy, and other materials.

[0083] It should be noted that the gas-water separator 113 can be implemented using existing technology, and will not be further explained here.

[0084] In some embodiments, the scrubbing module 12 includes a Venturi device 121 and a scrubbing device 122 sequentially arranged along the exhaust gas flow direction on the exhaust gas flow pipe 14. The Venturi device 121 is located between the gas outlet of the gas-liquid separator 113 and the scrubbing device 122. The scrubbing device 122 is located upstream of the combustion module.

[0085] By setting up the Venturi device 121, the Venturi effect can be utilized to fully mix the washing liquid with the exhaust gas and spray it into the washing device 122, thereby improving the washing effect on the exhaust gas.

[0086] Specifically, the chambers within the washing device 122 can be divided into an air chamber 1221 and a liquid chamber 1222 by the washing liquid inside. The portion occupied by the washing liquid can be regarded as the liquid chamber 1222, and the remaining space within the chamber that is not filled with washing liquid can be regarded as the air chamber 1221.

[0087] The exhaust gas flow pipe 14 between the Venturi device 121 and the scrubbing device 122 extends from the inlet end of the scrubbing device 122 into the liquid chamber 1222, i.e., below the surface of the scrubbing liquid. The inlet end of the combustion module is connected to the outlet end of the scrubbing device 122 corresponding to the gas chamber 1221. The inlet end of the waste liquid treatment pipeline 30 is connected to the outlet end of the scrubbing device 122 corresponding to the liquid chamber 1222.

[0088] Thus, the exhaust gas flowing out of the gas outlet of the gas-liquid separator 113 first enters the Venturi device 121, mixes with the washing liquid, and is then sprayed out. The exhaust gas and washing liquid mixture sprayed out by the Venturi device 121 can be directly sprayed into the washing liquid in the washing device 122 through the exhaust gas flow pipe 14, and then further mixed and washed with the washing liquid in the washing device 122, improving the washing effect on the exhaust gas. The washed exhaust gas floats up to the gas chamber 1221 under the action of gravity, and flows into the combustion module through the outlet end of the washing device 122 corresponding to the gas chamber 1221.

[0089] After the exhaust gas is washed by the washing liquid in the washing device 122, the radioactive pollutants and residual hydrogen fluoride in the exhaust gas will remain in the washing liquid and mix to form waste liquid. This waste liquid can enter the waste liquid treatment pipeline 30 through the corresponding outlet end of the liquid chamber 1222 to achieve waste liquid treatment.

[0090] It should be noted that a regulating valve 70 can also be installed between the Venturi device 121 and the gas-liquid separator 113 to regulate the flow rate. When the negative pressure of the Venturi device 121 is too high, the regulating valve 70 can be used to regulate the system pressure and prevent the negative pressure from affecting the upstream system.

[0091] It should be noted that the specific composition of the washing solution needs to be flexibly adjusted according to the composition of the radioactive acidic exhaust gas, and is not specifically limited here. For example, the washing solution may include demineralized water or weak alkaline water to neutralize the effects of acidic gases such as hydrogen fluoride.

[0092] In some embodiments, the circulation pipeline 50 may include a circulation line 51 and at least one circulation pump 52. One end of the circulation line 51 is connected to the inlet end of the Venturi device 121, and the other end is connected to the outlet end of the washing device 122 corresponding to the liquid chamber 1222, for recycling the washing liquid flowing within the washing module. The circulation pump 52 is disposed on the circulation line 51 for adjusting the flow rate of the washing liquid within the circulation line 51.

[0093] Specifically, at least one valve 60 may be installed on the waste liquid treatment pipeline 30. By opening and closing the valve 60, the washing liquid in the washing module can be replaced, thus avoiding affecting the washing effect. The frequency of washing liquid replacement can be controlled by periodically checking the radioactivity and acid gas (hydrogen fluoride) concentration of the washing liquid in the washing device 122.

[0094] It should be understood that the negative pressure value of the Venturi device 121 can be controlled by adjusting the flow rate of the circulating liquid in the circulation pipeline 51. The circulation pump 52 can be set as a variable frequency pump, and the flow rate can be controlled by adjusting the pump frequency. Alternatively, the flow rate returning to the washing device 122 after the pump can be adjusted to achieve the effect of controlling the negative pressure value at the inlet of the Venturi device 121.

[0095] Furthermore, the number of circulating pumps 52 can be set to at least two. At least two circulating pumps 52 are connected in parallel on the circulating pipeline 51 to serve as backup equipment for each other. When a circulating pump 52 in operation fails, another normal circulating pump 52 can be switched to perform pumping operations at any time to ensure the normal and efficient operation of the radioactive hydrogen-containing tail gas treatment system 1.

[0096] It should be noted that each of the parallel branches where the circulating pumps 52 are located can be equipped with a valve 60 to control the operation status of each branch. At least one valve 60 can also be installed on the circulating pipeline 51.

[0097] In some other embodiments, the flow path of the washing liquid can also be configured as a non-circulating path. The washing liquid continuously enters the Venturi device 121 from the outside through the pipeline, and after the radioactive substances and residual hydrogen fluoride in the exhaust gas are washed away at the washing device 122, it flows out through the waste liquid treatment pipeline 30.

[0098] In some embodiments, the circulation line 50 may further include a diversion line 53, one end of which is connected to the circulation line 51 and the other end of which is connected to the washing device 122, so as to disperse the flow rate of the washing liquid entering the venturi device 121 and control the negative pressure of the venturi device 121.

[0099] Specifically, the inlet end of the diversion pipe 53 can be connected to the circulation pipe 51 located downstream of the circulation pump 52, so that the washing liquid can be pumped to the diversion pipe 53 by the circulation pump 52.

[0100] It should be noted that at least one valve 60 may be installed on the diversion pipe 53 to regulate the on / off state and flow rate of the diversion pipe 53.

[0101] In some other embodiments, a pump body may also be provided on the diversion pipeline 53, and its inlet end may also be provided at the circulation pipeline 51 located upstream of the circulation pump 52.

[0102] In some embodiments, the circulating pump 52 may be a flow-adjustable pump, such as an existing variable frequency pump, and the flow rate of the circulating liquid can be adjusted by adjusting the frequency of the variable frequency pump.

[0103] In some other embodiments, the circulation pump 52 may also be a pump with non-adjustable flow rate, and the flow rate entering the Venturi device 121 may be adjusted by adjusting the flow rate through the diversion line 53.

[0104] In some embodiments, the inner wall of the washing device 122 is also provided with an anti-corrosion layer to prevent corrosive substances such as hydrogen fluoride from corroding the washing device 122.

[0105] Specifically, the anti-corrosion layer can be made of polytetrafluoroethylene.

[0106] In other embodiments, the anti-corrosion layer may also be made of special fluoroplastics (such as soluble polytetrafluoroethylene PFA, perfluoroethylene propylene FEP, etc.), hydrofluoric acid resistant special coatings, acid resistant plastics (such as polyolefin PO, reinforced polypropylene FRPP, etc.), impermeable graphite, Monel alloy, and other materials.

[0107] In some embodiments, the waste liquid treatment pipeline 30 may include a waste liquid pipeline, one end of which is connected to the outlet end of the washing device 122 corresponding to the liquid chamber 1222, and the other end is connected to the waste liquid treatment system.

[0108] Specifically, the inlet end of the waste liquid pipeline can be connected to the downstream of the circulation pump 52 of the circulation pipeline 51, so that the washing liquid in the washing module can be pumped into the waste liquid treatment pipeline 30 by the circulation pump 52.

[0109] In some other embodiments, the washing device 122 may be provided with multiple outlet ends corresponding to the liquid chamber 1222, and the waste liquid pipeline may also be directly connected to the outlet ends corresponding to the liquid chamber 1222. By installing a pump body on the waste liquid pipeline, the circulating liquid can be pumped.

[0110] It should be noted that existing technologies can be used for the waste liquid treatment system, and no specific limitations are made here.

[0111] In some embodiments, the combustion module may include a flameless combustion device 13, which purifies the remaining hydrogen in the exhaust gas through MILD (Moderate and Intense Low-oxygen Dilution combustion) to ensure that the exhaust gas ultimately meets emission standards.

[0112] MILD (Mild Flameless Combustion) technology controls the flow of combustion-supporting gases, such as methane or compressed air, to burn hydrogen in the exhaust gas under oxygen-deficient and high-temperature conditions, thereby achieving highly efficient hydrogen removal. Flameless combustion also significantly reduces the formation of harmful substances such as nitrogen oxides during combustion, making the treatment technology more efficient and cleaner.

[0113] It's important to understand that the treatment of radioactive hydrogen-containing gases in related technologies generally involves pressurized storage decay processes, hydrogen-oxygen recombination for volume reduction, and activated carbon delay treatment. Among these, pressurized storage is a mature, reliable, and simple process, but it requires sophisticated equipment and is complex to operate and maintain. Hydrogen-oxygen recombination technology reduces the hydrogen content in the waste gas to achieve volume reduction, but its control is complex, and improper control of hydrogen-oxygen concentrations can easily lead to safety risks such as explosions. Activated carbon delay decay technology relies primarily on activated carbon to remove radioactive pollutants, but it requires high-performance activated carbon, and for hydrogen-containing waste gases with high hydrogen concentrations, the decayed gas cannot be directly emitted.

[0114] This application utilizes a flameless combustion device 13 to remove high-concentration hydrogen from exhaust gas in a clean and efficient manner. Compared to traditional combustion technologies, the MILD flameless combustion method has lower equipment requirements, more gradual operation and maintenance, and simpler operation; the treated exhaust gas can be directly discharged. Compared to direct combustion or catalytic combustion, the MILD flameless combustion method results in a more uniform combustion zone temperature and a lower peak temperature, reducing the risk of combustion and explosion accidents, while effectively suppressing the formation of secondary pollutants such as high-temperature nitrogen oxides. Furthermore, the MILD flameless combustion method eliminates the need for a catalyst during combustion, reducing the limitations imposed by catalysts on fuel conditions.

[0115] It should be noted that the flameless combustion device 13 can be implemented using existing technology.

[0116] Understandably, the above-mentioned technical features can be used in any combination without restriction.

[0117] The above embodiments merely illustrate specific implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this application's patent. It should be noted that those skilled in the art can freely combine the above technical features without departing from the concept of this application, and can also make several modifications and improvements, all of which fall within the protection scope of this application. Therefore, any equivalent transformations and modifications made within the scope of the claims of this application should be covered by the claims of this application.

Claims

1. A radioactive hydrogen-containing tail gas treatment system, characterized in that, include: Exhaust gas flow pipeline (10), including: The condensation module includes at least one gas-liquid separator (113) and at least one condensation device for condensing hydrogen fluoride; the gas-liquid separator (113) is disposed downstream of the condensation device; Combustion module for burning hydrogen; as well as A washing module for washing radioactive contaminants and residual hydrogen fluoride, the washing module being connected to the gas outlet of the gas-water separator (113) and located upstream of the combustion module; and a cooling water pipeline (40) for supplying cooling water to the condensing device, the condensing device also being connected to the cooling water pipeline (40).

2. The radioactive hydrogen-containing tail gas treatment system according to claim 1, characterized in that, The condensation device includes at least one precooler (111) and at least one condenser (112), wherein the at least one condenser (112) is disposed between the at least one precooler (111) and the at least one gas-water separator (113).

3. The radioactive hydrogen-containing tail gas treatment system according to claim 2, characterized in that, The condensing equipment includes a precooler (111) and at least two condensers (112); the condensing module includes at least two gas-water separators (113); the at least two condensers (112) are arranged in parallel downstream of the precooler (111), and the at least two gas-water separators (113) are respectively arranged downstream of the at least two condensers (112).

4. The radioactive hydrogen-containing tail gas treatment system according to claim 2, characterized in that, The cooling water pipeline (40) includes a cooling water return pipeline (42) and a cooling water inlet pipeline (41) for supplying cooling water to the at least one condenser (112); the inlet end of the at least one condenser (112) is connected to the cooling water inlet pipeline (41), and the outlet end is connected to the cooling water return pipeline (42); the precooler (111) is connected to the cooling water return pipeline (42).

5. The radioactive hydrogen-containing tail gas treatment system according to claim 4, characterized in that, The cooling water pipeline (40) also includes at least one return water bypass (43); one end of the at least one return water bypass (43) is connected to the outlet end of the at least one condenser (112), and the other end is connected to the cooling water inlet pipeline (41) downstream of the precooler (111); at least one valve (60) for adjusting the flow rate is provided on the return water bypass (43).

6. The radioactive hydrogen-containing tail gas treatment system according to claim 4, characterized in that, The inlet and outlet ends of the at least one condenser (112) are respectively equipped with a temperature instrument and a flow meter; And / or, the at least one gas-liquid separator (113) is provided with a temperature probe for detecting the temperature of the condensate.

7. The radioactive hydrogen-containing tail gas treatment system according to claim 2, characterized in that, The precooler (111) is a shell-and-tube heat exchanger; and / or The at least one condenser (112) is a graphite condenser.

8. The radioactive hydrogen-containing tail gas treatment system according to any one of claims 1 to 7, characterized in that, The washing module includes a venturi device (121) and a washing device (122) containing washing liquid; the venturi device (121) is disposed between the at least one gas-water separator (113) and the washing device (122).

9. The radioactive hydrogen-containing tail gas treatment system according to claim 8, characterized in that, The chambers within the washing device (122) are divided into a gas chamber (1221) and a liquid chamber (1222) by the washing liquid; the outlet end of the Venturi device (121) extends into the liquid chamber (1222), and the combustion module is connected to the outlet end of the washing device (122) corresponding to the gas chamber (1221).

10. The radioactive hydrogen-containing tail gas treatment system according to claim 9, characterized in that, It also includes a circulation pipeline (50) for circulating the washing liquid in the washing module. The circulation pipeline (50) includes a circulation line (51) and at least one circulation pump (52) disposed on the circulation line (51). One end of the circulation line (51) is connected to the inlet end of the Venturi device (121), and the other end is connected to the outlet end of the washing device (122) corresponding to the liquid chamber (1222).

11. The radioactive hydrogen-containing tail gas treatment system according to claim 10, characterized in that, The number of the circulation pumps (52) is at least two, and at least two of the circulation pumps (52) are connected in parallel on the circulation pipeline (51).

12. The radioactive hydrogen-containing tail gas treatment system according to claim 10, characterized in that, The circulation pipeline (50) also includes a diversion pipeline (53), one end of which is connected to the circulation pipeline (51), and the other end is connected to the inlet end of the washing device (122).

13. The radioactive hydrogen-containing tail gas treatment system according to claim 8, characterized in that, The inner wall of at least one gas-water separator (113) is provided with an anti-corrosion layer; and / or The inner wall of the washing device (122) is provided with an anti-corrosion layer.

14. The radioactive hydrogen-containing tail gas treatment system according to any one of claims 1 to 7, characterized in that, Also includes: A recovery pipeline (20) for recovering hydrogen fluoride condensate is connected downstream of the liquid outlet of the gas-liquid separator (113); and / or A wastewater treatment pipeline (30) for collecting radioactive contaminants and residual hydrogen fluoride is located downstream of the washing module.

15. The radioactive hydrogen-containing tail gas treatment system according to any one of claims 1 to 7, characterized in that, The combustion module includes a flameless combustion device (13).

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