Method and system for the treatment of radioactive liquid waste

Abstract

Embodiments of the present application provide a radioactive waste liquid treatment method, comprising: driving radioactive waste liquid to circulate between a heating device and a separation device by a circulating pump, wherein the heating device is used for heating treatment of the radioactive waste liquid to evaporate the radioactive waste liquid in the separation device, the separation device is used for separating steam generated when the radioactive waste liquid evaporates, so that the radioactive waste liquid is concentrated, and the separation device is in a negative pressure environment; in the process of circulation, the steam separated by the separation device is compressed and heated by a steam compression device to obtain compressed steam, the compressed steam is introduced into the heating device as a first heat source of the heating device, so that the radioactive waste liquid can be continuously concentrated; after it is determined that the radioactive waste liquid has been concentrated by a predetermined multiple, the radioactive waste liquid is led out of the heating device and the separation device. Embodiments of the present application also provide a radioactive waste liquid treatment system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of radioactive substance processing, in particular to a radioactive waste liquid processing method and system. BACKGROUND

[0002] A large amount of radioactive waste liquid is often generated in process engineering related to nuclear technology, and the radioactive waste liquid needs to be concentrated. In the prior art, evaporation is usually used to concentrate the radioactive waste liquid. However, the process flow of the radioactive waste liquid processing in the prior art has high energy consumption. SUMMARY

[0003] To solve at least one of the technical problems in the prior art and other aspects, the present application provides a radioactive waste liquid processing method and system.

[0004] According to a first aspect of an embodiment of the present application, a radioactive waste liquid processing method is provided, including: driving radioactive waste liquid to circulate between a heating device and a separation device by means of a circulating pump, wherein the heating device is used for heating treatment of the radioactive waste liquid to evaporate the radioactive waste liquid in the separation device, and the separation device is used for separating steam generated when the radioactive waste liquid is evaporated, so that the radioactive waste liquid is concentrated, and the separation device is a negative pressure environment; in the process of circulation, the steam separated by the separation device is compressed and heated by means of a steam compression device to obtain compressed steam, the compressed steam is introduced into the heating device as a first heat source of the heating device, so that the radioactive waste liquid can be continuously concentrated; after it is determined that the radioactive waste liquid has been concentrated by a predetermined multiple, the radioactive waste liquid is led out of the heating device and the separation device.

[0005] According to a second aspect of the embodiments of the present application, a radioactive waste liquid treatment system is provided, comprising: a heating device, the heating device being formed with a liquid flow channel for the flow of radioactive waste liquid, and a gas flow channel arranged outside the liquid flow channel, a gas flowing in the gas flow channel being capable of exchanging heat with the radioactive waste liquid in the liquid flow channel to heat treat the radioactive waste liquid; a separation device, the separation device being used to separate steam in the radioactive waste liquid after the heating treatment to concentrate the radioactive waste liquid; a circulation pipeline, the circulation pipeline connecting the separation device and an inlet of the liquid flow channel; a circulation pump, the circulation pump being arranged in the circulation pipeline, and the circulation pump being used to drive the radioactive waste liquid to flow in the circulation pipeline between the heating device and the separation device; a steam compression device, the steam compression device being arranged between the separation device and an inlet of the gas flow channel, and the steam compression device being used to compress and heat the steam separated by the separation device to obtain compressed steam, the compressed steam being capable of being introduced into the gas flow channel as a first heat source of the heating device; a vacuum pump, the vacuum pump being in communication with the separation device, and the vacuum pump being used to extract gas in the separation device to build a negative pressure environment in the separation device; a feeding device, the feeding device being in communication with the heating device, and the feeding device being used to introduce the radioactive waste liquid into the liquid flow channel of the heating device; and a discharge outlet, the discharge outlet being arranged in the circulation pipeline, and the discharge outlet being used to lead out the concentrated radioactive waste liquid.

[0006] The radioactive waste liquid treatment method and system provided by the embodiments of the present application can significantly reduce the energy consumption in the evaporation and concentration treatment of the radioactive waste liquid. BRIEF DESCRIPTION OF DRAWINGS

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

[0008] Figure 2 FIG. 2 is a schematic diagram of a radioactive waste liquid treatment system according to another embodiment of the present application;

[0009] Figure 3 FIG. 3 is a schematic diagram of a radioactive waste liquid treatment system according to still another embodiment of the present application;

[0010] Figure 4 FIG. 4 is a schematic diagram of a radioactive waste liquid treatment system according to still another embodiment of the present application;

[0011] Figure 5 FIG. 5 is a schematic diagram of a radioactive waste liquid treatment system according to still another embodiment of the present application;

[0012] Figure 6 FIG. 6 is a schematic diagram of a radioactive waste liquid treatment system according to still another embodiment of the present application;

[0013] Figure 7 FIG. 7 is a schematic diagram of a radioactive waste liquid treatment system according to still another embodiment of the present application;

[0014] Figure 8 a schematic view of a buffer tank according to an embodiment of the present application;

[0015] Figure 9 a schematic view of a layout of a radioactive liquid waste treatment system according to an embodiment of the present application;

[0016] Figure 10 a schematic view of a support structure according to an embodiment of the present application. DETAILED DESCRIPTION

[0017] In order to make the objects, technical solutions, and advantages of the present application clearer, the following will further describe the present application with reference to the embodiments and the accompanying drawings.

[0018] Embodiments of the present application first provide a radioactive liquid waste treatment system, referring to Figure 1 , the radioactive liquid waste treatment system can include a heating device 1, a separation device 2, a circulating pump 3, a vapor compression device 4, and a feeding device 5.

[0019] The heating device 1 is used for heating treatment of the radioactive liquid waste, so that it can reach the boiling temperature. The heating device 1 can be a heat exchanger, for example, the heating device 1 can be formed with a liquid flow channel 11 for the flow of the radioactive liquid waste, and a gas flow channel 12 arranged outside the liquid flow channel 11. In the actual process of treating the radioactive liquid waste, the gas flowing in the gas flow channel 12 can exchange heat with the radioactive liquid waste flowing in the liquid flow channel 11, thereby heating the radioactive liquid waste. The specific arrangement of the liquid flow channel 11 and the gas flow channel 12 can refer to the heat exchanger provided in the related art, which will not be described here.

[0020] The separation device 2 is in communication with the liquid flow channel 11 of the heating device 1, so that the radioactive liquid waste heated by the gas flowing in the gas flow channel 12 can boil in the separation device 2, and the vapor formed during boiling is separated by the separation device 2, so that the radioactive liquid waste is concentrated. The separation device 2 can be formed with a cavity, and a gas outlet can be formed at the top of the cavity. The radioactive liquid waste heated by the heating device 1 can enter the cavity from the top of the cavity, and the vapor formed during boiling will leave the separation device 2 from the gas outlet at the top of the cavity, so that the radioactive liquid waste is concentrated. The concentrated radioactive liquid waste will be deposited at the bottom of the cavity.

[0021] The separation device 2 can also be in communication with the liquid flow channel 11 through a circulating pipeline 31, and the circulating pump 3 can be arranged on the circulating pipeline 31. During the treatment of the radioactive liquid waste, under the drive of the circulating pump 3, the remaining radioactive liquid waste after concentration will return to the liquid flow channel 11 of the heating device 1 and continue to circulate between the heating device 1 and the separation device 2, so as to repeat the above concentration process.

[0022] The vapor compression device 4 is arranged between the separation device 2 and the inlet of the gas flow channel 12, which can compress and heat the vapor separated by the separation device 2, and introduce the vapor into the gas flow channel of the heating device 1, so as to serve as a heat source of the heating device 1.

[0023] It can be understood that the vapor separated by the separation device 2 still has a large amount of residual heat energy, but the residual heat energy is insufficient to heat the radioactive waste liquid to boiling, and the vapor compression device 4 can compress the vapor separated by the separation device 2 to make it regain the ability to heat the radioactive waste liquid to boiling, thereby fully recycling the residual heat energy of the vapor separated by the separation device 2, and indirectly reducing the energy consumption in the process of treating the radioactive waste liquid.

[0024] The heating device 1 can be configured with multiple heat sources, that is, in addition to the compressed vapor generated by the vapor compression device 4, the heating device 1 can also be configured with other heat sources, which can be hot vapor generated by other devices, or some heating components arranged in the heating device 1, and the like. The other heat sources can supplement and replace the compressed vapor to provide heat required for the evaporation of the radioactive waste liquid, for example, when the treatment of the radioactive waste liquid is initially started, the amount of compressed vapor is small or even non-existent, at this time, other heat sources can be used to heat the radioactive waste liquid.

[0025] The feeding device 5 is in communication with the liquid flow channel 11 of the heating device 1, so as to introduce the radioactive waste liquid into the heating device 1. In some embodiments, the feeding device 5 can be in communication with the circulation pipeline 31, that is, indirectly in communication with the liquid flow channel 11 through the circulation pipeline 31. In some other embodiments, the feeding device 5 can also be directly in communication with the liquid flow channel 11 without the circulation pipeline 31. The feeding device 5 can be configured with a feeding pump, so as to provide power for the flow of the radioactive waste liquid.

[0026] In the actual process of treating the radioactive waste liquid, the radioactive waste liquid in the feeding device 5 can be continuously introduced into the liquid flow channel 11 at a certain rate, or can be stopped after a certain amount of radioactive waste liquid is introduced, and the next batch of radioactive waste liquid is introduced after the concentration of the currently introduced radioactive waste liquid is completed and introduced. This is not limited. It can be understood that in the continuous feeding embodiment, the operation is simple, but it can be difficult to accurately control the concentration multiple of the radioactive waste liquid. The batch feeding can accurately control the concentration multiple of the radioactive waste liquid, but the operator needs to operate frequently.

[0027] A discharge port 32 can be provided on the circulation pipeline 31, and when the radioactive waste liquid has been concentrated to the desired multiple, the radioactive waste liquid that has completed the concentration can be led out through the discharge port 32.

[0028] In the actual process of treating the radioactive waste liquid, sampling can be performed at the discharge port 32 to determine whether the radioactive waste liquid has been concentrated to the desired multiple, and / or the time required for the radioactive waste liquid to be concentrated to the desired multiple can be calculated according to the actual treatment efficiency of the radioactive waste liquid treatment system, and whether the radioactive waste liquid has been concentrated to the desired multiple is determined according to the time. When the feeding device 5 continuously introduces the radioactive waste liquid, the discharge port 32 can be opened after the radioactive waste liquid has been concentrated to the desired multiple, and the radioactive waste liquid can be continuously led out at a certain rate. When the feeding device 5 only introduces a certain amount of radioactive waste liquid, the discharge port 32 can be opened after the radioactive waste liquid has been concentrated to the desired multiple, and the radioactive waste liquid can be completely led out. Those skilled in the art can make settings according to actual conditions, which will not be described here.

[0029] In some embodiments, with reference to Figure 1 A pressure reducing valve 21 can be provided between the outlet of the liquid flow channel 11 of the heating device 1 and the inlet of the separation device 2, which can cause the pressure of the radioactive waste liquid in the heating device 1 to decrease after entering the separation device 2.

[0030] The pressure reducing valve 21 can be any suitable pressure reducing valve provided in the related art, which is not limited. The pressure reducing valve 21 can create a pressure difference between the liquid flow channel 11 and the separation device 2, so that the pressure of the radioactive waste liquid in the liquid flow channel 11 decreases after entering the separation device 2.

[0031] It can be understood that the boiling point of a liquid is related to the pressure, and when the pressure decreases, the boiling point will also decrease, so that the pressure reducing valve 21 can ensure that the radioactive waste liquid entering the separation device 2 boils, and further improve the utilization rate of the heat source of the heating device 1, thereby indirectly reducing the energy consumption of the radioactive waste liquid treatment system.

[0032] In some embodiments, during the actual radioactive waste liquid treatment process, the radioactive waste liquid in the liquid flow channel 11 can not be boiled, but can be boiled after entering the separation device 2, by adjusting the opening degree of the pressure reducing valve 21. It can be understood that if the radioactive waste liquid in the liquid flow channel 11 is boiled, a part of the steam generated by boiling will remain in the liquid flow channel 11, and the efficiency of gas-gas heat exchange is lower than that of gas-liquid heat exchange, so that the efficiency of heat exchange between the radioactive waste liquid in the liquid flow channel 11 and the gas in the gas flow channel 12 is reduced. In the present embodiment, the opening degree of the pressure reducing valve 21 is adjusted to ensure that the radioactive waste liquid in the liquid flow channel 11 is not boiled, thereby improving the utilization rate of the heat source and reducing the energy consumption.

[0033] In some embodiments, referring to Figure 2 , the radioactive waste liquid treatment system can further comprise a steam generating device 6, which is in communication with the inlet of the gas flow channel 12, so that the steam generated by the steam generating device 6 can enter the gas flow channel 12 to serve as a second heat source of the heating device 1. The steam generating device 6 can be any suitable device capable of heating and vaporizing water to generate steam, which is not limited.

[0034] In the present embodiment, the steam generating device 6 can serve as a second heat source of the heating device 1 to supplement the compressed steam, so that, as described above, the steam can serve as a heat source of the heating device 1 when the steam is not compressed, or serve as a heat source of the heating device 1 together with the compressed steam during the treatment process.

[0035] In some embodiments, in addition to the steam generating device 6, the heating device 1 can be provided with other heat sources, which are not described herein.

[0036] It can be understood that in the above embodiment, the heating efficiency of the heating device 1 is actually controlled by the working parameters of the steam compressing device 4 and the steam generating device 6, and during the actual radioactive waste liquid treatment process, the heating efficiency of the heating device 1 can be adjusted by adjusting any one of the two.

[0037] In some embodiments, it can be understood that the steam in the gas flow channel 12 will be condensed to form liquid after heat exchange with the radioactive waste liquid, and the gas flow channel 12 can be in communication with the inlet of the steam generating device 6, so that the condensed liquid in the gas flow channel 12 can enter the steam generating device 6 to serve as a water source of the steam generating device 6. In addition to the condensed liquid, the steam generating device 6 can have other water sources to ensure that the steam generating device 6 can continuously generate sufficient steam.

[0038] It can be understood that there is still a large amount of residual heat in the condensed liquid, and in the embodiment, the condensed liquid is introduced into the steam generating device 6 as a water source, so that the residual heat in the condensed liquid can be fully utilized, thereby reducing the energy required for the steam generating device 6 to generate steam, and further reducing the energy consumption of the radioactive waste liquid treatment system.

[0039] In some embodiments, the steam generating device 6 can be arranged below the heating device 1, so that the condensed liquid in the heating device 1 can flow into the steam generating device 6 by gravity.

[0040] In some other embodiments, it can be necessary to arrange the steam generating device 6 and the heating device 1 in the same horizontal plane to reduce the height of the entire radioactive waste liquid treatment system, at this time, it can be necessary to pump the condensed liquid in the heating device 1 into the steam generating device 6 by means of the condensed liquid pump 61.

[0041] Specifically, the condensed liquid pump 61 can be connected at the bottom of the gas flow channel 12 of the heating device 1, so that the condensed liquid deposited at the bottom of the gas flow channel 12 will be pumped into the steam generating device 6.

[0042] In some embodiments, it can be understood that the formation of condensed liquid requires a certain heat exchange time, and if the condensed liquid pump 61 is always turned on for pumping, the condensed liquid pump 61 can be in an idle state most of the time, therefore, a liquid level switch can be arranged at the condensed liquid pump 61, which can automatically turn on the condensed liquid pump 61 when it senses that the liquid level of the condensed liquid in the gas flow channel 12 reaches a certain height, and turn off the condensed liquid pump 61 in other cases, so as to avoid the idling of the condensed liquid pump 61.

[0043] In some embodiments, the radioactive waste liquid treatment system can further include a preheating device 7, which can be arranged between the feeding device 5 and the heating device 1, and can preheat the radioactive waste liquid entering the liquid flow channel 11 from the feeding device 5. It can be understood that the radioactive waste liquid stays in the liquid flow channel 11 for a limited time in one cycle, which can not be enough to raise its temperature to the required temperature for boiling, therefore, in the embodiment, the radioactive waste liquid is preheated, thereby improving the efficiency of the radioactive waste liquid. The preheating device 7 can be a heat exchanger, or other devices with heat exchange or heating functions, which are not limited.

[0044] In some embodiments, the steam generating device 6 can communicate with the preheating device 7, so that the condensed liquid in the steam generating device 6 can enter the preheating device 7 to serve as a heat source for the preheating device 7. Specifically, two liquid flow channels can be formed in the preheating device 7, and the condensed liquid and the radioactive waste liquid can flow in the two liquid flow channels respectively, so that the condensed liquid and the radioactive waste liquid can exchange heat.

[0045] As described above, the condensate also contains residual heat energy, and in this embodiment, the condensate is used as a heat source for preheating, thereby more fully utilizing the residual heat energy, thereby reducing the energy consumption of the radioactive waste liquid treatment system.

[0046] In some embodiments, during the actual radioactive waste liquid treatment process, the flow rate of the condensate introduced into the preheating device 7 can be determined by monitoring the temperature of the radioactive waste liquid at the outlet of the preheating device 7, for example, if the temperature of the radioactive waste liquid is less than the desired preheating temperature, the flow rate of the condensate introduced into the preheating device 7 can be increased.

[0047] It can be understood that if the flow rate of the condensate introduced into the preheating device 7 is too large, it can cause the water level in the steam generating device 6 to be too low, thereby causing the steam generating device 6 to be unable to generate sufficient steam. For this reason, in some embodiments, the water level in the steam generating device 6 can also be monitored, and if the temperature of the radioactive waste liquid is less than the desired preheating temperature and the water level in the steam generating device 6 is less than a predetermined water level, the temperature after preheating can be increased by reducing the rate at which the radioactive waste liquid is introduced from the supply device 5 to the preheating device 7.

[0048] In some embodiments, the radioactive waste liquid treatment system further comprises a condensate recovery device 62, which can be in communication with the preheating device 7, thereby recovering the condensate in the preheating device 7.

[0049] In some embodiments, with reference to Figure 3 The steam generated by the steam generating device 6 can also be introduced into the inlet of the steam compression device 4. It can be understood that the steam compression device 4 is provided with a compressor, and when the flow rate of the compressor is reduced, or the pressure difference between the inlet and the outlet is large, surging can occur, which will seriously affect the performance or service life of the steam compression device 4. In this embodiment, the steam generated by the steam generating device 6 is also introduced into the inlet of the steam compression device 4, thereby being able to supplement the steam when the flow rate of the steam separated by the separation device 2 is small, ensuring the flow rate of the steam at the inlet of the steam compression device 4, and avoiding the occurrence of surging.

[0050] In some embodiments, a make-up valve can be provided in the passage between the vapor compression device 4 and the vapor generation device 6. During the actual treatment of the radioactive liquid waste, the working current of the vapor compression device 4 can be monitored. When the variation of the working current of the vapor compression device 4 is greater than a preset threshold, i.e., abnormal fluctuation occurs, the make-up valve is opened to introduce the steam from the vapor generation device 6 to the inlet of the vapor compression device 4 to avoid the occurrence of surge. In some other embodiments, the pressure, gas flow, etc. at the inlet of the vapor compression device 4 can also be monitored to determine whether the make-up valve needs to be opened for steam make-up.

[0051] Further, when the steam flow at the inlet of the vapor compression device 4 decreases, it means that the working efficiency of the heating device 1 is low, resulting in a low steam flow separated by the separation device 2. At this time, as described above, the efficiency of the concentration of the radioactive liquid waste can be controlled by adjusting the operating parameters of the vapor compression device 4 and / or the vapor generation device 6, thereby adjusting the steam flow.

[0052] For example, when the steam flow at the inlet of the vapor compression device 4 decreases, the rotational speed of the vapor compression device 4 can be increased. Alternatively, when the steam flow at the inlet of the vapor compression device 4 decreases, the power of the vapor generation device 6 can be increased. When the steam flow at the inlet of the vapor compression device 4 increases, the rotational speed of the vapor compression device 4 can be decreased. Alternatively, when the steam flow at the inlet of the vapor compression device 4 increases, the power of the vapor generation device 6 can be decreased.

[0053] In some embodiments, when the steam flow at the inlet of the vapor compression device 4 decreases, the gas pressure in the separation device 2 can be detected. If the gas pressure in the separation device 2 is higher than a preset pressure, the rotational speed of the vapor compression device 4 can be increased. If the gas pressure in the separation device 2 is lower than the preset pressure, the power of the vapor generation device 6 can be increased. In this embodiment, the gas pressure in the separation device 2 is used to select which device to adjust, thereby improving the effectiveness of the control.

[0054] In some embodiments, the condensed liquid in the vapor generation device 6 can be further introduced to the outlet of the vapor compression device 4 for certain spray cooling treatment of the compressed steam. It can be understood that the compressed steam can be compressed into superheated steam, which has a lower pressure than saturated steam. However, the superheated steam does not significantly improve the working efficiency of the heating device 1. Therefore, in this embodiment, the compressed steam is subjected to certain spray treatment so that it does not form superheated steam, thereby avoiding the occurrence of surge due to the excessively low pressure at the outlet of the vapor compression device 4 without affecting the heating efficiency of the heating device 1.

[0055] In some embodiments, the pressure at the outlet of the vapor compression device and the vapor temperature of the compressed vapor after the spraying are monitored, and if the vapor temperature is greater than the saturated vapor temperature at the current pressure at the outlet of the vapor compression device, the amount of condensate sprayed on the compressed vapor is increased. If the vapor temperature is less than the saturated vapor temperature at the current pressure, the amount of condensate sprayed is reduced or no spraying is performed, so as to avoid excessive spraying affecting the working efficiency of the heating device 1.

[0056] In some embodiments, it can be necessary to control the liquid level in the separation device 2 so that the radioactive waste liquid is boiled at a suitable liquid level to achieve better separation effect. For example, the liquid level in the separation device 2 can be adjusted by adjusting the power of the circulating pump 3, or the liquid level in the separation device 2 can also be adjusted by adjusting the feeding efficiency of the feeding device 5.

[0057] In some embodiments, when the liquid level in the separation device 2 rises, the rate of introducing the exothermic waste liquid from the feeding device 5 into the heating device 1 can be reduced. When the liquid level in the separation device 2 decreases, the rate of introducing the radioactive waste liquid from the feeding device 5 into the heating device 1 can be increased.

[0058] In some embodiments, with reference to Figure 4 , the feeding device 5 can be provided with a first pipeline 51 communicating with the heating device 1, the first pipeline 51 being used to introduce the radioactive waste liquid into the heating device 1, and a second pipeline 52 communicating with the feeding device 5 is arranged on the first pipeline 51, the second pipeline 52 being used to return part of the radioactive waste liquid in the first pipeline 51 to the feeding device 5. In the present embodiment, the rate of introducing the radioactive waste liquid into the heating device 1 can be adjusted by adjusting the rate of returning the radioactive waste liquid in the first pipeline 51 to the feeding device 5. As an example, a valve can be arranged on the second pipeline 52, and the rate of returning the radioactive waste liquid to the feeding device 5 can be adjusted by adjusting the opening degree of the valve.

[0059] Compared with directly adjusting the flow rate in the first pipeline 51, the adjustment mode provided in the present embodiment can avoid sudden changes in the flow rate, pressure, temperature, etc. of the radioactive waste liquid entering the radioactive waste liquid treatment system.

[0060] In some embodiments, with reference to Figure 5The radioactive waste liquid treatment system can further comprise a purifying device 8 arranged between the separating device 2 and the steam compression device 4, and the purifying device 8 is used for purifying the steam separated by the separating device 2 before the steam enters the steam compression device 4. As described above, the steam separated by the separating device 2 mainly comprises water, and the steam will become condensate liquid and be recycled subsequently, and some radioactive substances can be entrained in the steam, therefore, the purifying device 8 is arranged in the embodiment to purify the steam, so as to remove the radioactive substances entrained in the steam, and avoid that the radioactive content of the condensate liquid exceeds the standard.

[0061] The purifying mode of the purifying device 8 can be specifically arranged by the person skilled in the art according to actual needs, for example, a spray head can be arranged in the purifying device 8, and the steam entering the purifying device 8 can be sprayed to remove the radioactive substances entrained in the steam. Alternatively, a structure with a filtering function such as a wire mesh or a filler can be arranged in the purifying device 8, and the structure can filter and adsorb the radioactive substances entrained in the steam.

[0062] In some embodiments, a structure with a filtering function such as a wire mesh or a filler can also be arranged at the top of the separating device 2, and the structure can pre-purify the steam before the steam enters the purifying device 8, so as to further improve the purifying effect.

[0063] In some embodiments, as described above, a spray head 81 can be arranged in the purifying device 8, and the spray head 81 can spray the steam entering the purifying device 8. It can be understood that the temperature of the liquid used for spraying should not be too low, so as to avoid that a large amount of steam is condensed and heat is wasted. Therefore, in some embodiments, the condensate water in the steam generating device 6 can be introduced into the purifying device 8 as spraying water, and the condensate water has heat residues, so as to avoid that a large amount of steam is condensed during the spraying process.

[0064] The spraying water remaining after the spraying process can entrain a large amount of radioactive substances, therefore, in some embodiments, the spraying water after the spraying process can be introduced into the feeding device 5, so as to avoid radioactive leakage.

[0065] In some embodiments, referring to Figure 6 The spraying water dripping at the bottom of the purifying device 8 after the spraying process can be introduced into the spray head 81 for spraying, so as to avoid that too much condensate water is introduced into the spray head 81 for spraying, and heat waste is reduced.

[0066] In some embodiments, the spray water at the bottom of the purification device 8 can be introduced into the supply device 5 at intervals of a predetermined time. Further, after the liquid at the bottom of the purification device 8 is introduced into the supply device, the condensed liquid in the steam generating device 6 can be introduced into the spray head 81 to replenish the liquid for the spray treatment.

[0067] It can be understood that, during the circulation of the spray liquid, some steam may be condensed to cause the height of the spray liquid to rise, thereby affecting the purification efficiency. Therefore, in some embodiments, the pressure difference between the inlet and the outlet of the purification device 8 can also be monitored. When the pressure difference is greater than a predetermined pressure difference, some of the condensed liquid at the bottom of the purification device 8 can be introduced into the supply device 5, so as to ensure that the purification device 8 always has a high purification efficiency.

[0068] In some embodiments, with reference to Figure 7 The radioactive waste liquid treatment system can further include a vacuum pump 9 in communication with the separation device 2, which is used to extract the gas in the separation device 2 to build a negative pressure environment in the separation device 2. It can be understood that building a negative pressure environment in the separation device 2 helps to further improve the efficiency of boiling the radioactive waste liquid in the separation device 2.

[0069] In some embodiments, a first gas extraction port 91 can be provided at the outlet of the separation device 2, and a second gas extraction port 92 can be provided on the gas flow channel 12 of the heating device 1. The vacuum pump 9 can extract gas from the first gas extraction port 91 and / or the second gas extraction port 92 to build a negative pressure environment. The first gas extraction port 91 and the second gas extraction port 92 provided in the present embodiment help to improve the efficiency of building a negative pressure environment.

[0070] In some embodiments, building a negative pressure environment can be performed before introducing the radioactive waste liquid. In some embodiments, the gas pressure in the separation device 2 can also be monitored during the treatment of the radioactive waste liquid. If the gas pressure is higher than the desired negative pressure, a certain amount of gas can be extracted from the above-mentioned gas extraction ports to maintain the negative pressure environment.

[0071] In some embodiments, the vacuum pump 9 can also be used to extract non-condensable gas in the heating device 1. As described above, the gas entering the heating device 1 will condense into condensed water after heat exchange. However, some gas that cannot be condensed, i.e., non-condensable gas, may be mixed in the heating device 1. When a large amount of non-condensable gas accumulates in the heating device 1, the overall temperature of the gas in the heating device 1 will be reduced, thereby affecting the heating efficiency of the heating device 1. Therefore, the vacuum pump 9 can be used to extract the non-condensable gas in the heating device 1 to avoid the accumulation of non-condensable gas. Specifically, the non-condensable gas can be extracted from the above-mentioned second gas extraction port 92.

[0072] In some embodiments, the non-condensable gas can be extracted every interval of predetermined time, or the temperature of the liquid in the separation device 2 can be monitored, and if the temperature of the liquid in the separation device 2 is lower than the evaporation temperature, it means that the heating efficiency is reduced, at this time, the vacuum pump 9 can be started to extract the non-condensable gas in the heating device 1.

[0073] It can be understood that, whether in the process of constructing a negative pressure environment or in the process of extracting non-condensable gas, the extracted gas contains a large amount of steam, and the extraction of these steams will be likely to condense in the vacuum pump 9, thereby affecting the working efficiency and service life of the vacuum pump 9. Therefore, in some embodiments, the radioactive liquid waste treatment system can further comprise a cooling device 93 arranged on the path between the vacuum pump 9 and the separation device 2, and the cooling device 93 is used for cooling the gas extracted by the vacuum pump 9, so as to recover the steam in the gas extracted by the vacuum pump 9 into condensate.

[0074] In some embodiments, it can be understood that when the power of the vacuum pump 9 is large, part of the condensate in the cooling device 93 can also be extracted. Therefore, with reference to Figure 8 A buffer tank 94 can be arranged between the vacuum pump 9 and the cooling device 93, and the buffer tank 94 is used for storing the condensate to avoid the condensate being extracted into the vacuum pump 9.

[0075] Specifically, the buffer tank 94 can comprise a first buffer tank 941, a second buffer tank 942, a first valve 943, and a second valve 944. The first buffer tank 941 is in communication with the vacuum pump 9 and the cooling device 93. The second buffer tank 942 is arranged below the first buffer tank 941. The first valve 943 is arranged at the connection between the first buffer tank 941 and the second buffer tank 942. The second valve 944 is arranged to communicate the second buffer tank 942 with the atmosphere.

[0076] It can be understood that, during the process of extracting gas, if the buffer tank is completely sealed, the vacuum pump 9 can not be able to continuously extract gas due to air pressure problems, and if the buffer tank is in communication with the atmosphere, the gas flow channel 12 of the separation device 2, the heating device 1, etc. can be directly communicated with the atmosphere, which can have the risk of radioactive leakage. Therefore, two buffer tank structures are arranged in the present embodiment.

[0077] Specifically, when the vacuum pump 9 is started and the height of the condensate in the first buffer tank 941 is lower than a preset value, the first valve 943 can be closed. When the height of the condensate in the first buffer tank 941 is higher than the preset value, it means that the pressure in the first buffer tank 941 is already high at this time, and the second valve 944 can be closed and the first valve 943 can be opened, so that the condensate in the first buffer tank 941 enters the second buffer tank 942, thereby releasing the pressure in the first buffer tank 941.

[0078] When all the condensate in the first buffer tank 941 is transferred into the second buffer tank 942, the first valve 943 can be closed and the second valve 944 can be opened to balance the pressure in the second buffer tank 942, so that when more condensate is accumulated in the first buffer tank 941 next time, the second valve 944 can still be closed and the first valve 943 can be opened to release the pressure in the first buffer tank 941.

[0079] In the embodiment, the first valve 943 and the second valve 944 are not opened at the same time, so that the vacuum pump 9 can continuously extract the gas, and the separation device 2, the gas flow channel 12, etc. are not directly connected with the atmosphere.

[0080] In some embodiments, the second buffer tank 942 can be connected with the condensate recovery device 62, and a third valve 945 can be arranged at the connection between the second buffer tank 942 and the condensate recovery device 62. In the embodiment, after the condensate in the first buffer tank 941 is transferred into the second buffer tank 942, the first valve 943 can be closed and the second valve 944 and the third valve 945 can be opened to guide the condensate in the second buffer tank 942 into the condensate recovery device 62.

[0081] In some embodiments, the vacuum pump 9 can be connected with a filter device 95, and the filter device 95 can be connected with an exhaust pipe 96. The filter device 95 can be used to filter radioactive substances in the gas extracted by the vacuum pump 9, and the exhaust pipe 96 can be used to discharge the filtered gas.

[0082] In some embodiments, the exhaust pipe 96 can be arranged in a segmented structure, and the segments can be detached from each other or slide relative to each other. In the state without radioactive waste liquid treatment, the segments of the exhaust pipe 96 can be detached or folded relative to each other to avoid the limitation of movement due to the high height.

[0083] In some embodiments, referring to Figure 9 and Figure 10 , the radioactive waste liquid treatment system further comprises a support platform 100, and the above-mentioned devices can be fixed on the support platform 100. In the embodiment, the above-mentioned devices are fixed on the same horizontal plane, so that the height of the radioactive waste liquid treatment system in the vertical plane is reduced, and the overall structure of the radioactive waste liquid treatment system is more compact, which is convenient for arrangement in a relatively narrow space.

[0084] In some embodiments, the support platform 100 can be fixed to a movable platform, thereby making the entire radioactive waste treatment system mobile and allowing its application scenarios to extend beyond a factory building. The movable platform can be a vehicle equipped with a cargo compartment, in which the support platform 100 and the aforementioned devices can be fixed. As described above, the devices in the radioactive waste treatment system of this embodiment are fixed on the same horizontal plane, ensuring that the overall radioactive waste treatment system of this embodiment meets the height restrictions for vehicle travel, thus enabling it to freely travel on roads to the required locations for radioactive waste treatment.

[0085] In some embodiments, the liquid flow channel 11 and gas flow channel 12 of the heating device 1 described above are arranged parallel to the support platform 100. That is, the heating device 1 adopts a horizontal design, thereby ensuring that the liquid flow channel 11 and gas flow channel 12 are long enough to meet the height requirements.

[0086] In some embodiments, the feeding device 5, heating device 1, separating device 2 and steam compression device 4 may be arranged sequentially along the first direction of the support platform 100.

[0087] Furthermore, in some embodiments, the steam generator 6 and the steam compressor 4 may be arranged side by side along the second direction of the support platform 100.

[0088] Understandably, compared to the feeding device 5, heating device 1, and separation device 2, the radioactivity content in the steam compression device 4 and steam generator 6 is lower. Therefore, by placing the steam compression device 4 and steam generator 6 side by side on one side of the above three devices, the entire radioactive waste liquid treatment system is divided into high-radioactivity and low-radioactivity areas, which helps to ensure the safety of operators.

[0089] In some embodiments, the radioactive waste treatment system may include a partition extending in a second direction, with the steam generator 4 and the steam compressor 6 disposed on the side of the partition away from the separation device 2. In this embodiment, the partition further isolates low-radioactive devices such as the steam generator 4 and the steam compressor 6 from high-radioactive devices, thereby ensuring safety. As described above, the support platform 100 and the aforementioned devices can be housed within a vehicle compartment, and the partition can be sealed to the compartment, thus placing the low-radioactive devices such as the steam generator 4 and the steam compressor 6 in two relatively sealed partitions from the high-radioactive devices.

[0090] In some embodiments, the condensate recovery device 62 may be located on the side of the vapor compression device 4 away from the separation device 2, that is, it is also located in the partition where the low radioactivity device is located.

[0091] In some embodiments, the circulating pump 3 and the purification device 8 can be arranged on both sides of the heating device 1 along the second direction of the support platform 100. In some embodiments, the preheating device 7 can be arranged between the feeding device 5 and the purification device 8.

[0092] In some embodiments, some devices without control equipment and electrical equipment, such as an electrical cabinet for providing power for the above-mentioned devices, and a controller for controlling the start, operation, and monitoring the operating parameters of the above-mentioned devices, etc., can also be arranged on the above-mentioned support platform 100. Since these devices do not have radioactivity, they can be arranged on the side of the steam generation device 4, the steam compression device 6, the condensate recovery device 62, etc. away from the separation device 2, and can also be isolated from the above-mentioned devices by means of a partition, so that the entire radioactive waste liquid treatment system is divided into three areas of high radiation, low radiation, and no radiation.

[0093] As described above, there are a plurality of pipelines between the above-mentioned devices, some of which are used for the transfer of condensate, and some of which are used for the extraction and transfer of gas. In some embodiments, the pipelines used for the transfer of condensate can be arranged along the surface of the support platform 100, and the pipelines used for the extraction and transfer of gas can be arranged along the top surface of the above-mentioned devices.

[0094] In some embodiments, with reference to Figure 10 , the support platform 100 includes a support plate 110 and a support frame 120. The support frame 120 is arranged above the support plate 110 and forms a gap between the support plate 110 and the support frame 120. In the present embodiment, the above-mentioned devices can be connected to the support frame 120. Understandably, liquid leakage can occur during the operation of the above-mentioned devices, and since a gap is formed between the support frame 120 and the support plate 110, the leaked liquid can be collected in the gap to prevent it from flowing everywhere.

[0095] In some embodiments, the side of the support plate 110 facing the support frame 120 is formed with an inclination. Thus, the liquid leaked into the above-mentioned gap will flow along the inclination to a corner of the support plate 110, facilitating the collection of the leaked liquid.

[0096] Specifically, the inclination of the support plate 110 can be a very small angle, and at the same time, the support surface of the support frame 120 can be horizontal to ensure the stability of the support of the above-mentioned devices.

[0097] Embodiments of the present application also provide a radioactive waste liquid treatment method, which can be applied to the radioactive waste liquid treatment system described in one or more embodiments above.

[0098] Specifically, the radioactive waste liquid treatment method comprises:

[0099] S1: driving the radioactive waste liquid to circulate between a heating device and a separation device by means of a circulating pump, wherein the heating device is used for heating treatment of the radioactive waste liquid to evaporate the radioactive waste liquid in the separation device, the separation device is used for separating the steam generated when the radioactive waste liquid is evaporated, so that the radioactive waste liquid is concentrated, and the separation device is in a negative pressure environment.

[0100] S2: in the process of circulation, the steam separated by the separation device is compressed and heated by means of a steam compression device to obtain compressed steam, and the compressed steam is introduced into the heating device as the first heat source of the heating device, so that the radioactive waste liquid can be continuously concentrated;

[0101] S3: after determining that the radioactive waste liquid has been concentrated by a predetermined multiple, the radioactive waste liquid is led out of the heating device and the separation device.

[0102] In some embodiments, a negative pressure environment can be established in the separation device by means of a vacuum pump in communication with the separation device.

[0103] In some embodiments, the gas in the separation device can be extracted by means of the vacuum pump before starting to treat the radioactive waste liquid, so as to establish a negative pressure environment in the separation device.

[0104] In some embodiments, the pressure in the separation device can also be monitored during the circulation process, and if the pressure in the separation device is higher than the expected negative pressure, the vacuum pump is started to extract the gas in the separation device, so as to maintain the negative pressure environment in the separation device.

[0105] In some embodiments, the non-condensable gas in the heating device can also be extracted by means of the above-mentioned vacuum pump.

[0106] In some embodiments, the outlet of the separation device is provided with a first gas extraction port, and the heating device is provided with a second gas extraction port, and when establishing the negative pressure environment, the gas in the separation device can be extracted from one of the first gas extraction port and the second gas extraction port; when extracting the non-condensable gas in the heating device, the second gas extraction port can be extracted.

[0107] In some embodiments, the temperature of the liquid in the separation device can be monitored, and if the temperature of the liquid in the separation device is lower than the evaporation temperature, the vacuum pump is started to extract the non-condensable gas in the heating device.

[0108] In some embodiments, during the process of establishing a negative pressure environment in the separation device and extracting the non-condensable gas in the heating device by means of the vacuum pump, the gas extracted by the vacuum pump can be cooled by means of a cooling device to recover the steam in the gas extracted by the vacuum pump as a condensate.

[0109] In some embodiments, the condensate recovered by the cooling device can be introduced into the radioactive waste liquid.

[0110] Some specific technical details of the radioactive waste liquid treatment method can refer to the description of the related part of the radioactive waste liquid treatment system in the foregoing, and will not be described here again.

[0111] The application has been described in detail above in combination with the drawings and embodiments, but the application is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the application. The contents not described in detail in the application can adopt the prior art.

Claims

1. A method for treating radioactive liquid waste, comprising: driving the radioactive liquid waste to circulate between a heating device and a separation device by a circulating pump, wherein the heating device is configured to heat the radioactive liquid waste to evaporate the radioactive liquid waste in the separation device, and the separation device is configured to separate the steam generated by the evaporation of the radioactive liquid waste to concentrate the radioactive liquid waste, and the separation device is in a negative pressure environment; compressing the steam separated by the separation device by a steam compression device to obtain compressed steam, and introducing the compressed steam into the heating device as a first heat source of the heating device to enable the radioactive liquid waste to be continuously concentrated; after determining that the radioactive liquid waste has been concentrated by a predetermined multiple, leading the radioactive liquid waste out of the heating device and the separation device; the heating device is formed with a liquid flow channel for the flow of the radioactive liquid waste, and a gas flow channel arranged outside the liquid flow channel; an inlet of the gas flow channel is in communication with a steam generation device, and the steam generated by the steam generation device can enter the gas flow channel to serve as a second heat source of the heating device; the steam generation device and the heating device are fixed on the same horizontal plane, and the condensed liquid in the heating device is introduced into the steam generation device by a condensed liquid pump; purifying the steam separated by the separation device before entering the steam compression device by a purifying device; the purifying device is provided with a spray head, and the purifying process further comprises: spraying the steam separated by the separation device by the spray head after the steam enters the purifying device; reintroducing the sprayed water dripping on the bottom of the purifying device into the spray head for spraying; introducing the moisture on the bottom of the purifying device into a feeding device every interval of a predetermined time; after introducing the liquid on the bottom of the purifying device into the feeding device, introducing the condensed liquid in the steam generation device into the spray head to replenish the liquid for the spraying process; monitoring the pressure difference between the inlet and the outlet of the purifying device, and when the pressure difference is greater than a preset pressure difference, introducing part of the condensed liquid on the bottom of the purifying device into the feeding device.

2. The method of claim 1, further comprising: constructing a negative pressure environment in the separation device by a vacuum pump in communication with the separation device.

3. The method of claim 2, wherein, constructing the negative pressure environment comprises: before starting to treat the radioactive liquid waste, extracting the gas in the separation device by the vacuum pump to construct the negative pressure environment in the separation device.

4. The method of claim 3, wherein, constructing the negative pressure environment further comprises: during the circulation, monitoring the pressure in the separation device, and if the pressure in the separation device is higher than the expected negative pressure, starting the vacuum pump to extract the gas in the separation device to maintain the negative pressure environment in the separation device.

5. The method of claim 4, further comprising: extracting the non-condensable gas in the heating device by the vacuum pump.

6. The method of claim 5, wherein, The outlet of the separation device is provided with a first suction port, and the heating device is provided with a second suction port, and the vacuum pump is used to build a negative pressure environment in the separation device, which includes: extracting the gas in the separation device from one of the first suction port and the second suction port; extracting the non-condensable gas in the heating device, which includes: extracting the non-condensable gas in the heating device from the second suction port.

7. The method of claim 5 or 6, further comprising: monitoring the temperature of the feed liquid in the separation device, and if the temperature of the feed liquid in the separation device is lower than the evaporation temperature, starting the vacuum pump to extract the non-condensable gas in the heating device.

8. The method of claim 5, further comprising: during the process of building a negative pressure environment in the separation device by the vacuum pump and extracting the non-condensable gas in the heating device, cooling the gas extracted by the vacuum pump by a cooling device to recover the steam in the gas extracted by the vacuum pump as condensate.

9. The method of claim 8, further comprising: introducing the condensate recovered by the cooling device into the radioactive waste liquid.

10. A system for treating radioactive waste liquid, comprising: a heating device, which is formed with a liquid flow channel for the flow of radioactive waste liquid, and a gas flow channel outside the liquid flow channel, and the gas flowing in the gas flow channel can exchange heat with the radioactive waste liquid in the liquid flow channel to heat treat the radioactive waste liquid; a separation device, which is used to separate the steam in the heated radioactive waste liquid to concentrate the radioactive waste liquid; a circulation pipeline, which connects the separation device and the inlet of the liquid flow channel; a circulation pump, which is arranged in the circulation pipeline and is used to drive the radioactive waste liquid to flow in the circulation pipeline between the heating device and the separation device; a steam compression device, which is arranged between the separation device and the inlet of the gas flow channel, and is used to compress and heat the steam separated by the separation device to obtain compressed steam, and the compressed steam can be introduced into the gas flow channel as a first heat source of the heating device; a vacuum pump, which communicates with the separation device and is used to extract the gas in the separation device to build a negative pressure environment in the separation device; a feed device, which communicates with the heating device and is used to introduce the radioactive waste liquid into the liquid flow channel of the heating device; a discharge port, which is arranged in the circulation pipeline and is used to discharge the concentrated radioactive waste liquid; the system further comprises: a steam generation device, which communicates with the inlet of the gas flow channel, so that the steam generated by the steam generation device can enter the gas flow channel as a second heat source of the heating device; the steam generation device and the heating device are fixed on the same horizontal plane; a condensate pump, which is used to introduce the condensate in the heating device into the steam generation device. A purifying device is arranged between the separating device and the vapor compression device, and is used to purify the vapor separated by the separating device before the vapor enters the vapor compression device; A nozzle is arranged in the purifying device, and is configured to spray the vapor separated by the separating device after the vapor enters the purifying device, to drip the sprayed vapor at the bottom of the purifying device, to re-introduce the dripping water at the bottom of the purifying device into the nozzle for spraying, and to introduce the moisture at the bottom of the purifying device into the feeding device at a predetermined interval; The vapor generating device is configured to introduce the condensate in the vapor generating device into the nozzle to replenish the liquid for the spraying after the liquid at the bottom of the purifying device is introduced into the feeding device; The purifying device is configured to monitor the pressure difference between the inlet and the outlet of the purifying device, and to introduce part of the condensate at the bottom of the purifying device into the feeding device when the pressure difference is greater than a preset pressure difference.

11. The system of claim 10, wherein, The vacuum pump is also used to extract the non-condensable gas in the heating device.

12. The system of claim 11, wherein, A first gas extraction port is arranged at the outlet of the separating device, and a second gas extraction port is arranged on the gas flow channel of the heating device, and the vacuum pump is communicated with the separating device via the first gas extraction port and the second gas extraction port.

13. The system of claim 11, further comprising: A cooling device is arranged on the path between the vacuum pump and the separating device, and is used to cool the gas extracted by the vacuum pump to recover the vapor in the gas extracted by the vacuum pump as condensate.

14. The system of claim 11, further comprising: A filtering device is communicated with the outlet of the vacuum pump, and is used to filter the radioactive substances in the gas extracted by the vacuum pump.

15. The system of claim 14, further comprising: An exhaust pipe is detachably arranged at the outlet of the filtering device, and is used to discharge the gas in the filtering device.

16. The system of claim 15, wherein, The exhaust pipe is arranged in a segmented structure.

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