Radioactive waste liquid treatment system

Abstract

The embodiment of the present application discloses a radioactive waste liquid treatment system. The system comprises: a feeding device for storing radioactive waste liquid to be treated; an evaporator connected with the feeding device for evaporative concentration of the radioactive waste liquid; the evaporator comprises: a heating device and a separation device; a circulating pump arranged on a circulating pipeline for driving the radioactive waste liquid to circulate between the separation device and the heating device; a steam compression device arranged between the separation device and the inlet of the heating cavity, the steam compression device is used for compressing and heating the secondary steam, and the secondary steam is used as the first heat source of the heating device; a residual liquid storage container connected with the heating device for receiving and storing the residual liquid formed by the concentrated radioactive waste liquid after evaporation; wherein the feeding device, the heating device, the separation device, the circulating pump, the steam compression device and the residual liquid storage container are arranged at different height positions of a supporting device.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of radioactive waste treatment technology, specifically to a radioactive waste liquid treatment system. Background Technology

[0002] Currently, the treatment of radioactive waste liquid usually uses evaporation concentration technology. This technology mainly involves sending preheated radioactive waste liquid into an evaporator, using high-temperature steam to heat the radioactive waste liquid in the evaporator, so that the radioactive waste liquid is evaporated and separated into steam and concentrate. The steam can be directly discharged after condensation, while the concentrate needs further treatment.

[0003] However, traditional evaporation and concentration technologies mostly employ dedicated heat sources, requiring a continuous input of new steam to heat the feed liquid, resulting in high energy consumption. Furthermore, the large amount of secondary steam generated within the evaporator is directly condensed using cooling water, which prevents heat recovery and consumes cooling water. Summary of the Invention

[0004] Embodiments of the present invention also provide a radioactive waste liquid treatment system. The system includes: a feeding device for storing radioactive waste liquid to be treated; an evaporator connected to the feeding device for evaporating and concentrating the radioactive waste liquid; the evaporator includes: a heating device having a heating chamber for providing a flow channel for heating steam, and a liquid flow channel for the radioactive waste liquid to flow within the heating chamber, wherein the heating steam can exchange heat with the radioactive waste liquid to heat-treat the radioactive waste liquid; a separation device connected to the liquid flow channel of the heating device for vapor-liquid separation of the boiled radioactive waste liquid after heat treatment to form secondary steam, thereby concentrating the radioactive waste liquid; and a circulation pipeline connected to both the separation device and the heating device. The devices are interconnected, providing a channel for the radioactive waste liquid to circulate between the heating device and the separation device; a circulation pump, installed on the circulation pipeline, is used to drive the radioactive waste liquid to circulate between the separation device and the heating device; a vapor compression device, installed between the inlet of the separation device and the heating chamber, is used to compress and heat the secondary steam, serving as the primary heat source for the heating device; a residual vapor storage container, connected to the heating device, is used to receive and store the residual vapor formed after the radioactive waste liquid has been concentrated through evaporation; wherein, the feeding device, heating device, separation device, circulation pump, vapor compression device, and residual vapor storage container are installed at different heights on the supporting device.

[0005] The method and system described in this embodiment can recover and utilize the heat energy of the secondary steam generated by the evaporation of radioactive waste liquid, reduce the amount of cooling water used, and greatly reduce the energy consumption in the evaporation treatment process of radioactive waste liquid. Attached Figure Description

[0006] Other objects and advantages of the invention will become apparent from the following description of embodiments of the invention with reference to the accompanying drawings, and will help to provide a comprehensive understanding of the invention.

[0007] Figure 1 This is a schematic diagram of a radioactive waste liquid treatment system according to an embodiment of the present invention.

[0008] Figure 2 This is a schematic diagram of a separation device according to an embodiment of the present invention.

[0009] Figure 3 This is a schematic diagram of a purification device according to an embodiment of the present invention.

[0010] Figure 4 This is a schematic diagram of the layout of a radioactive waste liquid treatment system according to an embodiment of the present invention.

[0011] Figure 5 This is a schematic diagram of the arrangement of a radioactive waste liquid treatment system on a support device according to an embodiment of the present invention.

[0012] Figure 6 yes Figure 5 A schematic diagram of the layout of a radioactive waste liquid treatment system from another perspective.

[0013] It should be noted that the accompanying drawings are not necessarily drawn to scale, but are shown only in a schematic manner without affecting the reader's understanding. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only one embodiment of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the described embodiments of this application without creative effort are within the scope of protection of this application.

[0015] It should be noted that, unless otherwise defined, the technical or scientific terms used in this application should have the ordinary meaning understood by a person with ordinary skill in the art to which this application pertains. Where the terms "first," "second," etc., are used throughout the text, they are used only to distinguish similar objects and should not be construed as indicating or implying their relative importance, order of precedence, or implicitly specifying the number of technical features indicated. It should be understood that the data described by "first," "second," etc., can be interchanged where appropriate. Where "and / or" appears throughout the text, it means including three parallel solutions. Taking "A and / or B" as an example, it includes solution A, or solution B, or a solution that satisfies both A and B. Furthermore, for ease of description, spatial relative terms such as "above," "below," "top," "bottom," etc., may be used here, only to describe the spatial positional relationship between one device or feature as shown in the figure and other devices or features. It should be understood that this also includes different orientations in use or operation besides those shown in the figure.

[0016] During the operation, decontamination, and decommissioning of nuclear industrial facilities, a large amount of radioactive waste liquid is inevitably generated. Due to the large volume of radioactive waste liquid generated, especially intermediate and low-level radioactive waste liquid, it is necessary to treat it to reduce its volume and facilitate solidification. In this embodiment of the invention, the radioactive waste liquid is evaporated. The water vapor formed by the evaporation of the radioactive waste liquid has reduced radioactivity intensity and can be directly discharged after condensation and cooling. The volume of the remaining concentrated liquid after evaporation is greatly reduced, and after solidification treatment, it is stored, thereby reducing the storage volume of the radioactive waste liquid and facilitating subsequent transportation.

[0017] Figure 1 A schematic diagram of a radioactive waste treatment system according to an embodiment of the present invention is shown. Figure 1 As shown, the radioactive waste liquid treatment system in this embodiment of the invention includes an evaporator, a vapor compression device 20, and a residual vapor storage container 42. The evaporator heats the radioactive waste liquid to boil and evaporate it into steam, which is then concentrated to form residual vapor. The vapor compression device 20 is connected to the evaporator and compresses and heats the steam formed by the evaporation of the radioactive waste liquid in the evaporator to form heating steam. This heating steam is then transported to the evaporator to exchange heat with the radioactive waste liquid within the evaporator, serving as the primary heat source for the evaporation of the radioactive waste liquid. The residual vapor storage container 42 is connected to the evaporator and is used to receive and store the residual vapor formed after the radioactive waste liquid in the evaporator has been concentrated.

[0018] like Figure 1As shown, the evaporator in this embodiment is a split-type evaporator, which includes a heating device 11 and a separation device 12. The heating device 11 has a heating chamber with a liquid flow channel inside. The liquid flow channel is used for the flow of radioactive waste liquid, and the high-temperature gas flowing in the heating chamber can exchange heat with the radioactive waste liquid in the liquid flow channel to heat the radioactive waste liquid. The separation device 12 is connected to the liquid flow channel of the heating device 11 and is used to perform vapor-liquid separation on the boiling radioactive waste liquid, thereby concentrating the radioactive waste liquid.

[0019] Furthermore, a circulation pipe is provided between the liquid flow channel of the heating device 11 and the separation device 12 to provide a channel for the circulation of radioactive waste liquid between the heating device 11 and the separation device 12. Specifically, the separation device 12 is located above the heating device 11. The heating device 11 has an inlet at its bottom and an outlet at its top. The separation device 12 has an outlet at its bottom and an inlet on its side wall. The circulation pipe includes a first circulation pipe 13 and a second circulation pipe 14. The first circulation pipe 13 connects the inlet at the bottom of the heating device 11 and the outlet at the bottom of the separation device 12. The second circulation pipe 14 connects the outlet at the top of the heating device 11 and the inlet on the side wall of the separation device 12, thereby allowing the radioactive waste liquid in the separation device 12 to flow downwards into the heating device 11, and the radioactive waste liquid in the heating device 11 to flow upwards into the separation device 12, forming a circulation.

[0020] In some embodiments, the separation device 12 is disposed above the heating device 11, and the radioactive waste liquid can circulate between the heating device 11 and the separation device 12 by relying on its own sealing difference. Specifically, after the radioactive waste liquid is heated to boiling in the heating device 11, it flows upward into the separation device 12 due to the decrease in density, while the radioactive waste liquid in the separation device 12 increases in density due to evaporation and concentration, and can flow downward into the heating device 11, thereby forming a natural circulation between the heating device 11 and the separation device 12, ensuring the continuity of the dynamic circulation of the radioactive waste liquid.

[0021] In some embodiments, a circulation pump 82 is provided on the first circulation pipe 13 to control the forced circulation of radioactive waste liquid between the heating device 11 and the separation device 12. Compared with natural circulation, this can increase the amount of radioactive waste liquid that the evaporator can process and the heat transfer efficiency, thereby improving the treatment efficiency of the radioactive waste liquid.

[0022] It should be noted that the evaporator in this embodiment is equipped with a working liquid level. After the material is fed into the evaporator to the working liquid level, heating and circulation begin. Furthermore, during normal operation of the radioactive waste treatment system, the radioactive waste liquid in the evaporator also needs to be maintained at the working liquid level. In this embodiment, the inlet of the separation device 12 is located at the working liquid level of the evaporator.

[0023] In some embodiments, the evaporator's discharge port is located on the first circulation pipe 13, between the circulation pump 82 and the heating device 11. A discharge pipe 103 connects the residual evaporation liquid storage container 42 and the discharge port. The residual evaporation liquid formed by evaporation and concentration in the evaporator is discharged through the discharge pipe 103 into the residual evaporation liquid storage container 42 for storage, facilitating subsequent processing. Furthermore, a discharge valve can be installed on the discharge pipe 103 to control the evaporator's discharge rate.

[0024] In some embodiments, the feed inlet of the evaporator may also be located on the first circulation pipe 13, between the circulation pump 82 and the separation device 12, and above the bottom of the heating device 11. In this embodiment, the discharge speed is kept constant by controlling the discharge valve, while the feed speed of the radioactive waste liquid into the evaporator is kept constant, so that continuous feeding and discharging can be maintained, and the operation of the entire treatment system can be kept stable.

[0025] like Figure 1 As shown, the processing system in this embodiment also includes a feeding device 41, which is connected to the inlet of the evaporator and is used to store the radioactive waste liquid to be treated. The radioactive waste liquid in the feeding device 41 can be fed into the evaporator for evaporation treatment. Specifically, a feed pipe 101 is connected between the feeding device 41 and the first circulation pipe 13. A feed pump 81 is installed on the feed pipe 101, which can transport the radioactive waste liquid in the feeding device 41 sequentially through the feed pipe 101 and the first circulation pipe 13 into the evaporator.

[0026] In addition, the processing system also includes a return pipe 102, one end of which is connected to the feeding device 41 and the other end to the feed pipe 101. At least a portion of the radioactive waste liquid in the feed pipe 101 can be returned to the feeding device 41 via the return pipe 102. In this embodiment, a return valve is provided on the return pipe 102. The flow rate of the radioactive waste liquid in the return pipe 102 can be controlled by adjusting the return valve, thereby controlling the feed flow rate of the radioactive waste liquid into the evaporator, thus preventing pressure fluctuations in the radioactive waste liquid in the feed pipe 101 and ensuring a stable feed of the radioactive waste liquid.

[0027] Furthermore, the inlet of the vapor compressor 20 is connected to the separator 12, and the outlet of the vapor compressor 20 is connected to the heating chamber of the heating device 11. The boiled radioactive waste liquid, after heat treatment, evaporates in the separator 12 to form secondary steam. The secondary steam is discharged from the top of the separator 12 to the vapor compressor 20, where it is compressed and heated to form heating steam. The heating steam is then transported to the heating chamber of the heating device 11 to exchange heat with the radioactive waste liquid in the liquid flow channel of the heating device 11, thereby achieving the heat treatment of the radioactive waste liquid.

[0028] In this embodiment, a vapor compression device 20 is used to recover the latent heat of the secondary steam generated during the evaporation of radioactive waste liquid. This allows the pressurized and heated secondary steam to be used as a heat source to heat the subsequent feed radioactive waste liquid, eliminating the need for a dedicated boiler room for heating and reducing energy consumption during the evaporation treatment of radioactive waste liquid.

[0029] like Figure 1 As shown, the radioactive waste liquid treatment system in this embodiment also includes a steam generator 30. The steam generator 30 can generate high-temperature steam and is connected to the evaporator, thereby providing a second heat source for heating the radioactive waste liquid in the evaporator. The steam generator 30 can serve as a heat source for the evaporator during the start-up of the treatment system, and can also provide supplementary steam to the evaporator during normal operation of the treatment system to compensate for heat loss.

[0030] Specifically, the steam generator 30 has a water-containing cavity and an electric heating element inside, which heats the water in the cavity to form high-temperature steam. In this embodiment, the steam generator 30 is connected to the heating cavity of the heating device 11, thereby providing a heat source for the heating device 11 to heat the radioactive waste liquid. The high-temperature steam generated by the steam generator 30 enters the heating cavity of the heating device 11 and exchanges heat with the radioactive waste liquid, causing the radioactive waste liquid to boil. In addition, the steam generated by the steam generator 30 and the pressurized and heated secondary steam exchange heat in the heating device 11 to form a condensate with a certain temperature, which then flows back into the steam generator 30, thereby keeping the liquid level in the steam generator 30 stable.

[0031] In some embodiments, the steam generated by the steam generator 30 can be delivered to the inlet of the steam compressor 20 to prevent surge in the steam compressor 20. Compared to the conventional method of circulating superheated steam from the outlet of the steam compressor 20 to the inlet of the steam compressor 20, in this embodiment, high-temperature and high-pressure heating steam is delivered to the heating device 11 for heat exchange before entering the steam generator 30. This allows the steam in the steam generator 30 to enter the steam compressor 20 from the inlet, thus avoiding excessively high inlet temperature of the steam compressor 20.

[0032] like Figure 1As shown, the processing system also includes a preheating device. The evaporator is connected to the preheating device. When evaporating radioactive waste liquid, the preheating device is used to preheat the radioactive waste liquid before it is conveyed to the evaporator. In this embodiment, the preheating device includes a first preheating device 51, which is disposed between the feeding device 41 and the evaporator for preheating the radioactive waste liquid. In this embodiment, the radioactive waste liquid is preheated in the first preheating device 51 before being conveyed to the evaporator. Specifically, the first preheating device 51 can be a heat exchanger. The first preheating device 51 is also connected to a steam generator 30, which provides a heat source for the first preheating device 51.

[0033] In this embodiment, the radioactive waste liquid is transported to the tube side of the first preheating device 51, and the hot water in the steam generator 30 is transported to the shell side of the first preheating device 51 to exchange heat with the radioactive waste liquid, thereby preheating the radioactive waste liquid at room temperature, reducing the temperature difference between the radioactive waste liquid and the phase transition temperature, and improving the efficiency of radioactive waste liquid treatment.

[0034] Furthermore, the processing system in this embodiment may also include a condensate storage container 43 connected to the first preheating device 51, for receiving and storing the condensate in the first preheating device 51 whose temperature has decreased after heat exchange with the radioactive waste liquid. In some embodiments, the processing system may not include a condensate storage container 43, and the condensate formed after heat exchange in the first preheating device 51 may be directly discharged.

[0035] In some embodiments, a cooling device is also provided on the condensate discharge pipe of the first preheating device 51. When the temperature of the condensate flowing out of the first preheating device 51 is high, the cooling device can cool and lower the temperature of the condensate before it is discharged. In this embodiment, the cooling device can be a heat exchanger, and cooling water serves as the cold source of the cooling device, used to exchange heat with the condensate to lower its temperature.

[0036] In some embodiments, the preheating device further includes a second preheating device 52, which is disposed between the first preheating device 51 and the evaporator. The second preheating device 52 is used to preheat the radioactive waste liquid again, so that the temperature of the radioactive waste liquid is raised to near the boiling point (e.g., 98°C) before being fed into the evaporator, thereby improving the evaporation and separation efficiency of the radioactive waste liquid.

[0037] In this embodiment, the radioactive waste liquid, after initial preheating, is transported to the tube side of the second preheating device 52, while steam is transported to the shell side of the second preheating device 52 to exchange heat with the radioactive waste liquid, thereby achieving reheating of the radioactive waste liquid, further increasing its temperature and improving treatment efficiency. The second preheating device 52 is connected to the steam generator 30. After heat exchange between the steam and the radioactive waste liquid, condensate is formed and flows into the steam generator 30 to replenish the water level within it.

[0038] It should be noted that during the startup phase, the steam used for preheating in the second preheating device 52 can be steam generated by the steam generator 30. The shell side of the second preheating device 52 is also connected to the heating chamber of the heating device 11. During normal operation, the steam used for preheating in the second preheating device 52 can be heating steam generated by the vapor compressor 20. This heating steam is then transported to the second preheating device 52 after passing through the heating chamber of the heating device 11, where it exchanges heat with the radioactive waste liquid. Furthermore, during normal operation, the steam generator 30 can also provide steam to the second preheating device 52 to compensate for system heat loss.

[0039] In some embodiments, a steam trap is also provided between the second preheating device 52 and the steam generating device 30, and a steam trap (not shown in the figure) can also be provided between the heating device 11 and the steam generating device 30. The steam trap is used to separate the condensate flowing out of the second preheating device 52 and the heating device 11 into vapor and liquid, so as to prevent the condensate from carrying gas into the steam generating device 30 and affecting the normal operation of the steam generating device 30.

[0040] Before the treatment system operates, a large amount of non-condensable gas (e.g., air) exists in the equipment, and a small amount of non-condensable gas is also generated during the heating of the radioactive waste liquid during system operation. To remove non-condensable gas from the treatment system, the treatment system in this embodiment is also equipped with a non-condensable gas emission and recovery device 70. For example... Figure 1 As shown, the non-condensable gas emission and recovery device 70 is connected to the second preheating device 52 and is used to discharge the non-condensable gas in the second preheating device 52 and recover the steam discharged from the second preheating device 52, so as to avoid excessive non-condensable gas in the second preheating device 52, which would affect the heat transfer efficiency.

[0041] Specifically, the non-condensable gas emission recovery device 70 is connected to the shell side of the second preheating device 52. Cooling water is introduced into the non-condensable gas emission recovery device 70. After the gas in the shell side of the second preheating device 52 is discharged into the non-condensable gas emission recovery device 70, it exchanges heat with the cooling water inside the non-condensable gas emission recovery device 70. The vapor in the discharged gas is condensed by the cooling water to form condensate, which can be directly discharged, while the non-condensable gas is directly discharged from the non-condensable gas emission recovery device 70. It should be noted that, in this embodiment, non-condensable gas refers to gas that will not be condensed by cooling water, such as air.

[0042] In this embodiment, the non-condensable gas emission recovery device 70 is also connected to the condensate storage container 43, and the condensate formed by the condensation of vapor in the non-condensable gas emission recovery device 70 can be recovered into the condensate storage container 43. When the condensate storage container 43 is not provided, the condensate generated in the non-condensable gas emission recovery device 70 is directly discharged.

[0043] In addition, the non-condensable gas emission and recovery device 70 in this embodiment can also be connected to the heating device 11 to discharge non-condensable gas in the heating chamber of the heating device 11 and recover the steam discharged by the heating device 11, so as to avoid excessive non-condensable gas in the heating device 11 and affect the heat exchange efficiency.

[0044] In some embodiments, the heating device 11 is provided with at least two exhaust ports. One exhaust port is connected to the second preheating device 52 for discharging the gas in the heating device 11 to the second preheating device 52, so that the steam therein exchanges heat with the radioactive waste liquid in the second preheating device 52; the other exhaust port is connected to the non-condensable gas emission and recovery device 70 for directly discharging the gas in the heating device 11 to the non-condensable gas emission and recovery device 70, so as to directly discharge the non-condensable gas in the heating device 11.

[0045] In addition, at least two exhaust ports are located at different heights of the heating device 11 and are connected to exhaust valves respectively to discharge gas from different locations within the heating device 11, thereby removing non-condensable gases. The exhaust valves are used to control the gas discharge.

[0046] Similarly, the second preheating device 52 is provided with at least two exhaust ports, which are located at different heights of the second preheating device 52 and are respectively connected to exhaust valves to discharge the gas at different locations in the second preheating device 52, thereby removing the non-condensable gas.

[0047] It should be noted that the processing system in this embodiment can be equipped with a cooling water storage container, which can store and provide cooling water. The cooling water can not only cool the condensate flowing out of the first preheating device 51, but also cool the steam in the non-condensable gas emission recovery device 70. In addition, the cooling water can also provide cooling for the oil tank and motor of the steam compression device 20, the circulating pump 82, and the mechanical seals of other pumps in the processing system.

[0048] like Figure 2 As shown, in some embodiments, the separation device 12 is equipped with a first demister 121 to remove radioactive waste liquid carried by the secondary steam generated from the evaporation of radioactive waste liquid, preventing the secondary steam from carrying droplets into the steam compression device and causing contamination. Specifically, the first demister 121 can be located at the top of the separation device 12, above the working liquid level of the evaporator.

[0049] In some embodiments, the first demister 121 includes a corrugated plate demister 1211, which comprises a plurality of corrugated plates arranged along the axial direction of the separation device 12, with gaps between the corrugated plates. When the secondary steam formed by the evaporation of radioactive waste liquid flows through the corrugated plate demister 1211, the secondary steam can flow out through the gaps between the corrugated plates. The droplets carried in the secondary steam collide with the corrugated plates at the bends and adhere to the surface of the corrugated plates, thereby defoaming the secondary steam and achieving initial purification of the secondary steam.

[0050] In some embodiments, the first demister 121 includes a wire mesh demister 1212, which is made of metal wire mesh. When the secondary steam formed by the evaporation of radioactive waste liquid flows through the wire mesh demister 1212, the droplets carried by the secondary steam are resisted and adhere to the metal wire, thereby playing the role of separating droplets and realizing the initial purification of the secondary steam.

[0051] Optionally, one of the corrugated plate demister 1211 and the wire mesh demister 1212 can be installed in the separation device 12. Alternatively, both the corrugated plate demister 1211 and the wire mesh demister 1212 can be installed in the separation device 12. The wire mesh demister 1212 can be installed below the corrugated plate demister 1211. Using two types of demisters to purify the secondary steam can greatly increase the demisting effect.

[0052] like Figure 1 As shown, the processing system in this embodiment also includes a purification device 60. The purification device 60 is connected between the separation device 12 and the steam compression device 20, and is used to purify the secondary steam formed by the evaporation of radioactive waste liquid in the separation device 12. After removing the radioactive substances mixed in the secondary steam, it is then transported to the steam compression device 20 to prevent the radioactive substances mixed in the secondary steam from causing radioactive contamination to the steam compression device 20 and the downstream steam generator 30.

[0053] Specifically, such as Figure 3 As shown, the purification device 60 is equipped with a second demister 61, which is used to demister the secondary steam entering the purification device 60, remove radioactive waste liquid mixed in the secondary steam, and achieve purification of the secondary steam. In some embodiments, the second demister 61 can be a wire mesh demister, and the liquid droplets mixed in the secondary steam can adhere to the wire mesh demister, thereby reducing the liquid mist entrained in the secondary steam.

[0054] like Figure 1 and Figure 3As shown, a spray element 62 is also provided on the top of the purification device 60. The spray element 62 sprays inside the purification device 60 to clean the secondary steam entering the purification device 60, so that the radioactive droplets carried by the secondary steam flow down with the spray liquid, thereby removing the radioactive substances mixed in the secondary steam and achieving the purpose of purifying the secondary steam.

[0055] In some embodiments, the spray element 62 is disposed above the second demister 61. While spraying and cleaning the secondary steam, the spray element 62 can also spray and clean the second demister 61, causing radioactive droplets adhering to the second demister 61 to flow with the spray liquid to the bottom of the purification device 60. Furthermore, the spray radiation angle of the spray element 62 can be no less than 90 degrees, thereby radiating spray in all directions to cover the entire interior of the purification device 60, achieving spray cleaning of the entire demister and the inner surface of the purification device 60.

[0056] Furthermore, the bottom of the purification device 60 contains spray liquid, and the spray element 62 is connected to the drain port at the bottom of the purification device 60 through a spray liquid pump 84. The spray liquid pump 84 can transport the spray liquid at the bottom of the purification device 60 to the spray element 62, so that the spray element 62 can use the spray liquid contained in the purification device 60 to spray the secondary steam, which not only ensures the purification effect, but also realizes the recycling of the spray liquid.

[0057] like Figure 1 As shown, the purification device 60 is connected to the steam generator, which can transport the condensate in the steam generator to the purification device 60 as a spray liquid. While ensuring the purification effect, it also avoids the need to set up a special water storage tank or water source to achieve spray cleaning, thus simplifying the treatment system.

[0058] Furthermore, when the concentration of radioactive material in the spray liquid contained in the purification device 60 reaches a predetermined concentration threshold, the spray liquid needs to be replaced with new spray liquid to ensure the purification effect of the spray liquid on the secondary steam. Specifically, the spray liquid in the purification device 60 can be discharged into the radioactive waste liquid feeding device 41 to facilitate the evaporation treatment of the radioactive spray liquid. Then, the condensate in the steam generator 30 is transported to the purification device 60 to replenish the spray liquid used for spray cleaning.

[0059] like Figure 1 and Figure 3As shown, the purification device 60 also includes a packing layer 63, which is located below the second demister 61 and above the surface of the spray liquid. The secondary steam entering the purification device 60 first passes through the packing layer 63, which enhances the contact and mass transfer between the secondary steam and the spray liquid, thus improving purification efficiency. Exemplarily, the packing layer 63 includes two fixed sieve plates and packing material disposed between them, thereby fixing the packing material within the purification device 60. Optionally, the packing material in this embodiment can be Pall ring packing. Due to its perforated ring walls, it greatly improves the utilization rate of the internal space and surface area of ​​the ring, resulting in low airflow resistance, uniform liquid distribution, and advantages such as high throughput, low resistance, and high separation efficiency.

[0060] In this embodiment, the air inlet of the purification device 60 is located below the packing layer 63, so that after the secondary steam enters the purification device 60, it flows sequentially through the packing layer 63, the second demister 61, and the spray element 62. Through the combined action of the packing, the demister, and the spray cleaning, the purification effect on the secondary steam is improved. In addition, the liquid level of the spray liquid contained in the purification device 60 can be higher than the air inlet, so that the secondary steam flows upward after being cleaned by the spray liquid, further improving the purification effect.

[0061] like Figure 1 As shown, the processing system in this embodiment also includes a condensate pump 83. The inlet of the condensate pump 83 is connected to the steam generator 30 to transport water heated to a certain temperature within the steam generator 30. Specifically, the outlet of the condensate pump 83 can be connected to the first preheating device 51 to transport hot water from the steam generator 30 to the shell side of the first preheating device 51 for initial preheating of the radioactive waste liquid. The outlet of the condensate pump 83 can also be connected to the purification device 60 to replenish the purification device 60 with spray liquid used for spray cleaning.

[0062] In addition, a spray point is provided on the outlet pipe 104 of the steam compressor 20, and the outlet of the condensate pump 83 can also be connected to the spray point to spray and cool the superheated steam in the outlet pipe 104 of the steam compressor 20, thereby reducing the temperature of the superheated steam and converting it into saturated steam, which is convenient to be provided to the heating device 11 and the second preheating device 52 as a heat source.

[0063] In this embodiment, the various devices are positioned at different heights on the support device. For example... Figure 6 As shown, the support device 200 has multiple layers, with the feeding device 41, the residual liquid storage container 42, the condensate storage container 43, the feeding pump 81, the circulation pump 82, the condensate pump 83, and the vapor compression device 20 arranged at the bottom layer of the support device 200. Specifically, the support device 200 can be a support frame, which can be made of steel structure.

[0064] The feeding device 41, the residual liquid storage container 42, and the condensate storage container 43 contain liquids, resulting in significant weight. Placing them on the bottom floor (e.g., at the ground level) prevents the heavy liquid storage tanks from affecting the structural strength of the support device and thus avoids the collapse of the support device 200. Similarly, the feeding pump 81, the circulation pump 82, and the condensate pump 83 are large and vibrate during operation; placing them on the bottom floor also prevents the support device 200 from collapsing. Likewise, the vapor compressor, due to its high rotation speed, also vibrates during operation; therefore, placing it on the bottom floor prevents the support device 200 from collapsing without affecting the gas pressure drop in the vapor compressor 20's inlet pipe.

[0065] In some embodiments, each pump is positioned next to its corresponding storage container for easy delivery of the corresponding liquid. For example, feed pump 81 is adjacent to feed device 41. Vapor compressor 20 is located between feed device 41 and residual liquid storage container 42 to save space.

[0066] like Figure 4 As shown, the first preheating device 51 and the steam generating device 30 are installed on the second layer of the support device, which is higher than the bottom layer. The first preheating device 51 is higher than the feeding device 41, so that the radioactive waste liquid can flow back into the feeding device 41 by its own gravity during unloading.

[0067] In this embodiment, the steam generator 30 is placed on the second layer, which is higher than the condensate pump 83. This can pressurize the inlet of the condensate pump 83, compensate for the negative pressure when the condensate pump 83 draws condensate from the steam generator 30, and prevent the pressure from dropping after the condensate enters the condensate pump 83, thus avoiding cavitation.

[0068] like Figure 4 As shown, the second preheating device 52 and the heating device 11 are arranged on the third layer of the support device. The third layer is higher than the second layer and is used to allow the condensate in the heating device 11 and the second preheating device 52 to flow back to the steam generator 30 by gravity.

[0069] like Figure 5 and Figure 6 As shown, in this embodiment, the heating device 11 can penetrate the third layer of the support device 200. A support portion 210 is provided in the middle of the heating device 11, and the support portion 210 is fixed to the support beam, thus achieving the installation and fixation of the heating device 11. Specifically, the support portion 210 can be welded to the outer surface of the heating device 11 and fixed to the support beam of the support device 200 by fasteners.

[0070] In some embodiments, the purification device 60 and the separation device 12 are disposed on the fourth layer of the support device 200. The separation device 12 is positioned higher than the heating device 11 to facilitate circulation of the radioactive waste liquid between the heating device 11 and the separation device 12. Specifically, the inlet of the separation device 12 is higher than the outlet at the top of the heating device 11 to prevent the circulation pipe connected to the top of the heating device 11 from bending downwards and affecting the flow of the radioactive waste liquid.

[0071] In this embodiment, the air inlet of the purification device 60 is lower than the liquid level of the spray liquid inside it. In this embodiment, the purification device 60 and the separation device 12 are set at the same height, which can prevent the spray liquid in the purification device 60 from entering the separation device 12.

[0072] Furthermore, the non-condensable gas emission recovery device 70 is installed on the fourth layer of the support device 200. Since the gas flows upward, in this embodiment, the non-condensable gas emission recovery device 70 is installed above the second preheating device 52 and the heating device 11 to facilitate the discharge of non-condensable gas from the system.

[0073] like Figure 5 and 6 As shown, in this embodiment, both the separation device 12 and the purification device 60 penetrate the fourth layer of the support device 200. Specifically, they can be fixed to the support device 200 using the same method as the heating device 11. Both the separation device 12 and the purification device 60 have a support portion 210 in the middle, which is fixed to the support beam, thus achieving the installation and fixation of the separation device 12 and the purification device 60.

[0074] Regarding the embodiments of the present invention, it should also be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to obtain new embodiments.

[0075] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A radioactive waste liquid treatment system, characterized in that, include: A feeding device for storing radioactive waste liquid to be treated; An evaporator, connected to the feeding device, is used to evaporate and concentrate radioactive waste liquid; The evaporator includes: A heating device having a heating chamber for providing a flow channel for heating steam, and a liquid flow channel for the flow of radioactive waste liquid within the heating chamber, wherein the heating steam can exchange heat with the radioactive waste liquid to heat the radioactive waste liquid; A separation device is connected to the liquid flow channel of the heating device, and is used to perform vapor-liquid separation on the boiling radioactive waste liquid after heat treatment to form secondary steam, so as to concentrate the radioactive waste liquid. A circulation pipeline, which is connected to both the separation device and the heating device, serves as a channel for the radioactive waste liquid to circulate between the heating device and the separation device. A circulation pump, installed on the circulation pipeline, is used to drive the radioactive waste liquid to circulate between the separation device and the heating device; A steam compression device is disposed between the separation device and the inlet of the heating chamber. The steam compression device is used to compress and heat the secondary steam and serve as the first heat source for the heating device. A residual liquid storage container, connected to the heating device, is used to receive and store the residual liquid formed by the concentration of the radioactive waste liquid after evaporation; The feeding device, heating device, separation device, circulating pump, steam compression device, and residual liquid storage container are arranged at different height positions of the support device. The radioactive waste treatment system also includes: A steam generator, comprising water, is configured to heat the water to produce steam. The steam generator is connected to a heating device to provide a second heat source for the heating device. The steam generated by the steam generator is delivered to the inlet of the steam compression device; A purification device, connected between the separation device and the vapor compression device, is used to purify the secondary steam formed by the evaporation of the radioactive waste liquid. The purification device includes a second demister and a spray system. The second demister is used to demister the secondary steam entering the purification device, removing radioactive waste liquid mixed in with the secondary steam. The spray nozzle sprays water within the purification device to clean the secondary steam entering the device, causing radioactive droplets carried by the secondary steam to flow down with the spray liquid. The spray element is positioned above the second demister; The bottom of the purification device contains spray liquid. The spray element is connected to the drain port at the bottom of the purification device via a spray liquid pump. The spray liquid pump delivers the spray liquid at the bottom of the purification device to the spray element, so that the spray element can circulate the spray liquid contained in the purification device to spray the secondary steam.

2. The system according to claim 1, characterized in that, The feeding device, the residual liquid storage container, the circulating pump, and the steam compression device are arranged at the bottom of the support device.

3. The system according to claim 2, characterized in that, The steam compression device is located between the feeding device and the residual liquid storage container.

4. The system according to claim 2, characterized in that, Also includes: A first preheating device is disposed between the feeding device and the evaporator. The first preheating device is connected to the steam generating device, which provides condensate to the first preheating device to preheat the radioactive waste liquid. A second preheating device is disposed between the first preheating device and the evaporator. The second preheating device is connected to the heating chamber of the heating device. The heating device is used to provide heating steam to the second preheating device to preheat the radioactive waste liquid in a secondary manner.

5. The system according to claim 4, characterized in that, The first preheating device and the steam generating device are arranged on the second layer of the support device, which is higher than the bottom layer.

6. The system according to claim 5, characterized in that, The second preheating device and the heating device are disposed on the third layer of the support device, which is higher than the second layer, so that the condensate in the heating device and the second preheating device can flow back to the steam generating device by gravity.

7. The system according to claim 6, characterized in that, A condensate pump is provided between the steam generator and the first preheating device, and the condensate pump is used to transport the condensate in the steam generator. The condensate pump is located on the bottom layer, below the steam generator.

8. The system according to claim 4, characterized in that, The purification device and the separation device are located on the fourth layer of the support device.

9. The system according to claim 8, characterized in that, Also includes: A non-condensable gas emission and recovery device is connected to the heating chamber of the heating device and the second preheating device, and is used to discharge non-condensable gas and recover steam in the heating device and the second preheating device. The non-condensable gas emission recovery device is located on the fourth layer of the support device.

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