CN116153551B - Radioactive waste liquid treatment method and system - Google Patents

Abstract

The embodiment of the present application provides a method for treating radioactive liquid waste, including: using a circulating pump to drive the radioactive liquid waste to circulate between a heating device and a separation device, wherein a pressure reducing valve is provided between the heating device and the separation device, and the pressure reducing valve reduces the pressure of the radioactive liquid waste in the heating device after entering the separation device; during the circulation process, using a steam compression device to compress and heat the steam separated by the separation device to obtain compressed steam, and introducing the compressed steam into the heating device, so that the compressed steam and the radioactive liquid waste are exchanged for heat, so as to serve as the first heat source of the heating device, so that the radioactive liquid waste can be continuously concentrated; after determining that the radioactive liquid waste has been concentrated by a predetermined multiple, the concentrated radioactive liquid waste is led out of the heating device and the separation device. The embodiment of the present application also provides a system for treating radioactive liquid waste.

Description

Radioactive liquid waste treatment method and system

Technical Field

The present application relates to the technical field of radioactive material treatment, and in particular to a method and system for treating radioactive waste liquid.

Background technique

A large amount of radioactive liquid waste is often generated in process engineering related to nuclear technology. These radioactive liquid wastes need to be concentrated, usually by evaporation. However, the process flow of radioactive liquid waste treatment used in related technologies has high energy consumption.

Summary of the invention

In order to solve at least one of the above-mentioned and other technical problems in the prior art, the present application provides a method and system for treating radioactive liquid waste.

According to a first aspect of an embodiment of the present application, a method for treating radioactive liquid waste is provided, comprising: driving the radioactive liquid waste to circulate between a heating device and a separation device by means of a circulation pump, wherein the heating device is used to heat the radioactive liquid waste so that the radioactive liquid waste boils in the separation device, the separation device is used to separate the steam generated when the radioactive liquid waste boils so as to concentrate the radioactive liquid waste, and a pressure reducing valve is provided between the heating device and the separation device, the pressure reducing valve reduces the pressure of the radioactive waste liquid in the heating device after the radioactive waste liquid enters the separation device; during the circulation process, 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, the compressed steam is exchanged with the radioactive waste liquid to serve as a first heat source of the heating device, so that the radioactive waste liquid can be continuously concentrated; after determining that the radioactive waste liquid has been concentrated by a predetermined multiple, the concentrated radioactive waste liquid is led out of the heating device and the separation device.

According to a second aspect of an embodiment of the present application, a radioactive waste liquid treatment system is provided, comprising: a heating device, the heating device is formed with a liquid flow channel for the flow of radioactive waste liquid, and a gas flow channel arranged outside the liquid flow channel, the gas flowing in the gas flow channel can exchange heat with the radioactive waste liquid in the liquid flow channel to heat the radioactive waste liquid; a separation device, the separation device is used to separate steam from the boiling radioactive waste liquid after the heating treatment to concentrate the radioactive waste liquid; a pressure reducing valve, arranged between the outlet of the liquid flow channel and the inlet of the separation device, the pressure reducing valve is used to reduce the pressure of the radioactive waste liquid in the heating device after entering the separation device; a circulation A pipeline, a circulation pipeline 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 circulate between the heating device and the separation device through the circulation pipeline; 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 introduce the compressed steam into the gas flow channel to serve as the first heat source of the heating device; a feeding device, which 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 lead out the concentrated radioactive waste liquid.

The radioactive liquid waste treatment method and system provided in the embodiments of the present application can significantly reduce the energy consumption during the evaporation and concentration treatment of radioactive liquid waste.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a radioactive waste liquid treatment system according to an embodiment of the present application;

FIG2 is a schematic diagram of a radioactive waste liquid treatment system according to another embodiment of the present application;

FIG3 is a schematic diagram of a radioactive waste liquid treatment system according to another embodiment of the present application;

FIG4 is a schematic diagram of a radioactive waste liquid treatment system according to yet another embodiment of the present application;

FIG5 is a schematic diagram of a radioactive liquid waste treatment system according to yet another embodiment of the present application;

FIG6 is a schematic diagram of a radioactive liquid waste treatment system according to yet another embodiment of the present application;

FIG7 is a schematic diagram of a radioactive liquid waste treatment system according to yet another embodiment of the present application;

FIG8 is a schematic diagram of a buffer tank according to an embodiment of the present application;

FIG9 is a schematic diagram of the layout of a radioactive waste liquid treatment system according to an embodiment of the present application;

FIG. 10 is a schematic diagram of a support structure according to an embodiment of the present application.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

The embodiment of the present application first provides a radioactive liquid waste treatment system. Referring to FIG. 1 , the radioactive liquid waste treatment system may include a heating device 1 , a separation device 2 , a circulation pump 3 , a steam compression device 4 , and a feeding device 5 .

The heating device 1 is used to heat the radioactive waste liquid so that it can reach a 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 radioactive waste liquid, and a gas flow channel 12 arranged outside the liquid flow channel 11. In the actual process of treating the radioactive waste liquid, the gas flowing in the gas flow channel 12 can exchange heat with the radioactive waste liquid flowing in the liquid flow channel 11, thereby heating the radioactive waste liquid. The specific arrangement of the liquid flow channel 11 and the gas flow channel 12 can refer to the heat exchanger provided in the relevant technology in the field, and will not be repeated here.

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

The separation device 2 can also be connected to the inlet of the liquid flow channel 11 by means of the circulation pipeline 31. The circulation pump 3 can be set on the circulation pipeline 31. When the radioactive waste liquid is treated, the radioactive waste liquid remaining after concentration can be returned to the liquid flow channel 11 of the heating device 1 under the drive of the circulation pump 3, and continue to circulate between the heating device 1 and the separation device 2, thereby repeating the above-mentioned concentration process.

The steam compression device 4 is arranged between the separation device 2 and the inlet of the gas flow channel 12. It can compress and heat the steam separated by the separation device 2 and introduce it into the gas flow channel of the heating device 1, thereby serving as a heat source for the heating device 1.

It can be understood that there is still a large amount of residual heat energy in the steam separated by the separation device 2, but the residual heat energy is not enough to heat the radioactive waste liquid to boiling. The steam compression device 4 can compress the steam separated by the separation device 2 so that it can regain the ability to heat the radioactive waste liquid to boiling. Therefore, the residual heat energy in the steam separated by the separation device 2 is fully recovered and utilized, which indirectly reduces the energy consumption in the process of treating the radioactive waste liquid.

The heating device 1 can be equipped with multiple heat sources, that is, in addition to the compressed steam generated by the steam compression device 4, it can also be equipped with other heat sources. The other heat sources can be hot steam generated by other devices, or some heating components arranged in the heating device 1. Other heat sources can be used as supplements and substitutes to provide the heat required for evaporation of radioactive waste liquid together with compressed steam. For example, when radioactive waste liquid treatment is initially started, the amount of compressed steam is small or even non-existent. At this time, other heat sources can be used to heat the radioactive waste liquid.

The feeding device 5 is connected to the liquid flow channel 11 of the heating device 1, so that the radioactive waste liquid is introduced into the heating device 1. In some embodiments, the feeding device 5 can be connected to the circulation pipeline 31, that is, indirectly connected to the liquid flow channel 11 through the circulation pipeline 31. In some other embodiments, the feeding device 5 can also be directly connected to the liquid flow channel 11 without the circulation pipeline 31. The feeding device 5 can be equipped with a feeding pump to provide power for the flow of the radioactive waste liquid.

In the actual process of treating radioactive liquid waste, the radioactive liquid waste in the feeding device 5 can be continuously introduced into the liquid flow channel 11 at a certain rate, or it can be stopped after a certain amount of radioactive liquid waste is introduced, and the next batch of radioactive liquid waste is introduced after the currently introduced radioactive liquid waste is concentrated and drawn out, and there is no limitation on this. It can be understood that in the embodiment of continuous feeding, the operation is relatively simple, but it may be difficult to more accurately control the multiple of the radioactive liquid waste being concentrated. Batch feeding can more accurately control the multiple of the radioactive liquid waste being concentrated, but it requires the operator to perform frequent operations.

The circulation pipeline 31 may be provided with a discharge port 32 , and when the radioactive waste liquid has been concentrated to a desired multiple, the concentrated radioactive waste liquid may be discharged through the discharge port 32 .

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

In some embodiments, referring 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. The pressure reducing valve 21 can reduce the pressure of the radioactive waste liquid in the heating device 1 after entering the separation device 2.

The pressure reducing valve 21 can be any suitable pressure reducing valve provided in the related art, and is not limited thereto. 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 is reduced after entering the separation device 2.

It can be understood that the boiling point of the liquid is related to the pressure. When the pressure drops, the boiling point will also drop. Therefore, with the help of the pressure reducing valve 21, it can be ensured that the radioactive waste liquid entering the separation device 2 boils, and the utilization rate of the heat source of the heating device 1 is further improved, thereby indirectly reducing the energy consumption of the radioactive waste liquid treatment system.

In some embodiments, during the actual treatment of radioactive liquid waste, the opening of the pressure reducing valve 21 can be adjusted to prevent the radioactive liquid waste in the liquid flow channel 11 from boiling, and the liquid waste will boil only after entering the separation device 2. It can be understood that if the radioactive liquid waste in the liquid flow channel 11 boils, a portion 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, thereby reducing the efficiency of heat exchange between the radioactive liquid waste in the liquid flow channel 11 and the gas in the gas flow channel 12. In this embodiment, by adjusting the opening of the pressure reducing valve 21, it can be ensured that the radioactive liquid waste in the liquid flow channel 11 does not boil, thereby improving the utilization rate of the heat source and reducing energy consumption.

In some embodiments, referring to FIG. 2 , the radioactive liquid waste treatment system may further include a steam generator 6, which is connected to the inlet of the gas flow channel 12, so that the steam generated by the steam generator 6 can enter the gas flow channel 12 to serve as a second heat source for the heating device 1. The steam generator 6 may be any suitable device that can heat and vaporize water to generate steam, and there is no limitation to this.

In this embodiment, the steam generating device 6 can serve as the second heat source of the heating device 1 to supplement the compressed steam, so that, as described above, it can serve as the heat source of the heating device 1 before the compressed steam is generated, or serve as the heat source of the heating device 1 together with the compressed steam during the processing.

In some embodiments, in addition to the steam generating device 6, the heating device 1 may also be configured with other heat sources, which will not be described in detail here.

It can be understood that in the above embodiment, the heating efficiency of the heating device 1 is actually jointly controlled by the working parameters of the steam compression device 4 and the steam generation device 6. In the actual process of radioactive liquid waste treatment, the heating efficiency of the heating device 1 can be adjusted by adjusting any one of the two.

In some embodiments, it can be understood that the steam in the gas flow channel 12 will condense to form liquid after heat exchange with the radioactive waste liquid, and the gas flow channel 12 can be connected to the inlet of the steam generator 6, so that the condensate in the gas flow channel 12 can enter the steam generator 6 and serve as a water source for the steam generator 6. In addition to the condensate, the steam generator 6 can also have other water sources to ensure that the steam generator 6 can continuously generate sufficient steam.

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

In some embodiments, the steam generating device 6 may be disposed below the heating device 1 , so that the condensate in the heating device 1 may flow into the steam generating device 6 by gravity.

In some other embodiments, it may be necessary to place the steam generating device 6 and the heating device 1 on the same horizontal plane to reduce the height of the entire radioactive waste liquid treatment system. In this case, it may be necessary to use a condensate pump 61 to pump the condensate in the heating device 1 into the steam generating device 6.

Specifically, the condensate pump 61 may be connected to the bottom of the gas flow channel 12 of the heating device 1 , so that the condensate deposited at the bottom of the gas flow channel 12 will be pumped into the steam generating device 6 .

In some embodiments, it can be understood that the formation of condensate requires a certain heat exchange time. If the condensate pump 61 is always turned on for pumping, the condensate pump 61 may be in an idling state most of the time. For this reason, a liquid level switch can be provided at the condensate pump 61. The liquid level switch can automatically turn on the condensate pump 61 when it senses that the liquid level of the condensate in the gas flow channel 12 reaches a certain height, and turn off the condensate pump 61 in other cases, thereby avoiding the idling of the condensate pump 61.

In some embodiments, the radioactive waste liquid treatment system may further include a preheating device 7, which may 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 during a cycle, which may not be enough to raise its temperature to the boiling temperature. For this reason, the radioactive waste liquid is preheated in this embodiment to improve the efficiency of the radioactive waste liquid treatment. The preheating device 7 may be a heat exchanger, or other devices with heat exchange or heating functions, which are not limited.

In some embodiments, the steam generating device 6 may be connected to the preheating device 7, so that the condensate 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 may be formed in the preheating device 7, and the condensate and the radioactive waste liquid may flow in the two liquid flow channels respectively, so that the condensate and the radioactive waste liquid can exchange heat.

As described above, there is also residual heat energy in the condensate, and in this embodiment, the condensate is used as a heat source for preheating, thereby making more effective use of the residual heat energy therein, thereby reducing the energy consumption of the radioactive waste liquid treatment system.

In some embodiments, during the actual process of radioactive waste liquid treatment, the flow rate of 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 lower than the desired preheating temperature, the flow rate of the condensate introduced into the preheating device 7 can be increased.

It is understandable that if the flow rate of the condensate introduced into the preheating device 7 is too large, the water level in the steam generating device 6 may be too low, and thus sufficient steam may not be generated in the steam generating device 6. To this end, in some embodiments, the water level in the steam generating device 6 may be further monitored. If the temperature of the radioactive waste liquid is lower than the desired preheating temperature and the water level in the steam generating device 6 is lower than the preset water level, the preheated temperature may be increased by reducing the rate at which the radioactive waste liquid is introduced from the feeding device 5 to the preheating device 7.

In some embodiments, the radioactive liquid waste treatment system further includes a condensate recovery device 62 , which can be connected to the preheating device 7 to recover the condensate in the preheating device 7 .

In some embodiments, referring to FIG. 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 equipped with a compressor, and when the flow rate of the compressor is reduced, or when the pressure difference between the inlet and the outlet is large, surge may 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, so that the steam can be supplemented when the steam flow rate separated by the separation device 2 is small, thereby ensuring the steam flow rate at the inlet of the steam compression device 4 and avoiding the occurrence of surge.

In some embodiments, a gas replenishment valve may be provided on the passage between the steam compression device 4 and the steam generation device 6. In the actual process of treating the radioactive liquid waste, the working current of the steam compression device 4 may be monitored. When the change in the working current of the steam compression device 4 is greater than a preset threshold, that is, when an abnormal fluctuation occurs, the gas replenishment valve is opened to introduce the steam of the steam generation device 6 into the inlet of the steam compression device 4 to avoid the occurrence of surge. In some other embodiments, it is also possible to determine whether the gas replenishment valve needs to be opened for gas replenishment by monitoring the pressure, gas flow, etc. at the inlet of the steam compression device 4.

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

For example, when the steam flow rate at the inlet of the steam compression device 4 decreases, the rotation speed of the steam compression device 4 can be increased. Alternatively, when the steam flow rate at the inlet of the steam compression device 4 decreases, the power of the steam generating device 6 can be increased. When the steam flow rate at the inlet of the steam compression device 4 increases, the rotation speed of the steam compression device 4 can be decreased. Alternatively, when the steam flow rate at the inlet of the steam compression device 4 increases, the power of the steam generating device 6 can be decreased.

In some embodiments, when the steam flow at the inlet of the steam 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 the preset pressure, the speed of the steam 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 steam generating device 6 can be increased. In this embodiment, the gas pressure in the separation device 2 is used to select which device to adjust the parameters, thereby improving the effectiveness of the control.

In some embodiments, the condensate in the steam generating device 6 can be further introduced into the outlet of the steam compression device 4 to perform a certain spray cooling treatment on the compressed steam. It can be understood that the compressed steam may be compressed into superheated steam. Compared with saturated steam, the pressure of superheated steam is lower, but superheated steam does not significantly improve the working efficiency of the heating device 1. For this reason, in this embodiment, the compressed steam is subjected to a certain spray treatment so that it does not form superheated steam, thereby avoiding the occurrence of surge caused by too low pressure at the outlet of the steam compression device 4 without affecting the heating efficiency of the heating device 1.

In some embodiments, the pressure at the outlet of the steam compression device and the steam temperature of the compressed steam after spraying are monitored. If the steam temperature is greater than the saturated steam temperature at the current pressure at the outlet of the steam compression device, the amount of condensate sprayed on the compressed steam is increased. If the steam temperature is less than the saturated steam temperature at the current pressure, the amount of condensate sprayed is reduced, or spraying is not performed, thereby avoiding excessive spraying treatment affecting the working efficiency of the heating device 1.

In some embodiments, it may be necessary to control the liquid level in the separation device 2 so that the radioactive waste liquid boils at a suitable liquid level to obtain a better separation effect. For example, the liquid level in the separation device 2 may be adjusted by adjusting the power of the circulation pump 3, or the liquid level in the separation device 2 may be adjusted by adjusting the feeding efficiency of the feeding device 5.

In some embodiments, when the liquid level in the separation device 2 increases, 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.

In some embodiments, referring to FIG. 4 , the feeding device 5 may be provided with a first pipeline 51 in communication with the heating device 1, the first pipeline 51 being used to introduce radioactive waste liquid into the heating device 1, the first pipeline 51 being provided with a second pipeline 52 in communication with the feeding device 5, the second pipeline 52 being used to allow part of the radioactive waste liquid in the first pipeline 51 to flow back into the feeding device 5, in this embodiment, the rate of introducing the radioactive waste liquid into the heating device 1 may be adjusted by adjusting the rate at which the radioactive waste liquid in the first pipeline 51 flows back into the feeding device 5. As an example, a valve may be provided on the second pipeline 52, and the rate at which the radioactive waste liquid flows back into the feeding device 5 may be adjusted by adjusting the opening of the valve.

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

In some embodiments, referring to FIG. 5 , the radioactive liquid waste treatment system may further include a purification device 8, which is disposed between the separation device 2 and the steam compression device 4, and the purification device 8 is used to purify the steam separated by the separation device 2 before entering the steam compression device 4. As described above, the steam separated by the separation device 2 is mainly composed of water, which will subsequently become condensate and be recovered, and which may contain some radioactive substances. Therefore, in this embodiment, a purification device 8 is provided to purify the steam to remove the radioactive substances contained in the steam and avoid the radioactive content of the condensate exceeding the standard.

Those skilled in the art can specifically set the purification method of the purification device 8 according to actual needs. For example, the purification device 8 can be provided with a nozzle, which can spray the steam entering the purification device 8 to remove the radioactive substances carried therein. Alternatively, the purification device 8 can be provided with structures with filtering functions such as wire mesh and filler, which can filter and adsorb the radioactive substances carried in the steam.

In some embodiments, a structure with filtering function such as a wire mesh or a filler may also be provided on the top of the separation device 2, which can perform a certain pre-purification on the steam before it enters the purification device 8, thereby further improving the purification effect.

In some embodiments, as described above, the purification device 8 may be provided with a nozzle 81, which can perform a spray treatment on the steam entering the purification device 8. It is understandable that the temperature of the liquid used for the spray treatment cannot be too low to avoid condensing a large amount of steam and causing a waste of heat. To this end, in some embodiments, the condensed water in the steam generating device 6 can be introduced into the purification device 8 as spray water. As described above, the condensed water has residual heat, which can avoid condensing a large amount of steam while spraying.

The spray water remaining after the spray treatment may contain more radioactive substances. Therefore, in some embodiments, the spray water after the spray treatment may be introduced into the feeding device 5 to avoid radioactive leakage.

In some embodiments, referring to FIG. 6 , the spray water dripping on the bottom of the purification device 8 after the spray treatment can be reintroduced into the nozzle 81 for spraying, thereby avoiding the introduction of excessive condensed water into the nozzle 81 for spraying treatment, thereby reducing heat waste.

In this embodiment, the spray water at the bottom of the purification device 8 can be introduced into the feeding device 5 at predetermined intervals. Further, after the liquid at the bottom of the purification device 8 is introduced into the feeding device, the condensate in the steam generating device 6 can be introduced into the spray head 81 to supplement the liquid used for the spraying treatment.

It is understandable that during the circulation of the spray liquid, some steam may condense, causing the height of the spray liquid to rise, thereby affecting the purification efficiency. For this reason, in some embodiments, the pressure difference between the inlet and outlet of the purification device 8 can also be monitored. When the pressure difference is greater than the preset pressure difference, part of the condensate at the bottom of the purification device 8 can be introduced into the feeding device 5, thereby ensuring that the purification device 8 always has a high purification efficiency.

In some embodiments, referring to FIG7 , the radioactive liquid waste treatment system may further include a vacuum pump 9, which is in communication with the separation device 2 and is used to extract gas from the separation device 2 to construct a negative pressure environment in the separation device 2. It can be understood that constructing a negative pressure environment in the separation device 2 helps to further improve the efficiency of boiling the radioactive liquid waste in the separation device 2.

In some embodiments, a first air extraction port 91 may be provided at the outlet of the separation device 2, a second air extraction port 92 may be provided on the gas flow channel 12 of the heating device 1, and the vacuum pump 9 may extract gas from the first air extraction port 91 and/or the second air extraction port 92 to construct a negative pressure environment. The first air extraction port 91 and the second air extraction port 92 provided in this embodiment help to improve the efficiency of constructing a negative pressure environment.

In some embodiments, the negative pressure environment may be constructed before the introduction of the radioactive waste liquid. In some embodiments, the gas pressure in the separation device 2 may 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 may be extracted from the above-mentioned gas extraction port to maintain the negative pressure environment.

In some embodiments, the vacuum pump 9 can also be used to extract the 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 non-condensable gas, that is, 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. For this reason, 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 second gas extraction port 92.

In some embodiments, non-condensable gas can be extracted once at a predetermined interval, or the temperature of the slurry in the separation device 2 can be monitored. If the temperature of the slurry 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 turned on to extract the non-condensable gas in the heating device 1.

It can be understood that, whether it is when constructing a negative pressure environment or when extracting non-condensable gas, the extracted gas contains a large amount of steam, and the extraction of these steam will likely condense in the vacuum pump 9, thereby affecting the working efficiency and life of the vacuum pump 9. For this reason, in some embodiments, the radioactive liquid waste treatment system may also include a cooling device 93, which is arranged on the passage between the vacuum pump 9 and the separation device 2. The cooling device 93 is used to cool the gas extracted by the vacuum pump 9 so as to recover the steam in the gas extracted by the vacuum pump 9 as condensate.

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 may also be extracted. For this reason, referring to Figure 8, a buffer tank 94 can be provided between the vacuum pump 9 and the cooling device 93. The buffer tank 94 is used to store the condensate to prevent the condensate from being extracted into the vacuum pump 9.

Specifically, the buffer tank 94 may include 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 connected to 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 connect the second buffer tank 942 to the atmosphere.

It is understandable that during the gas extraction process, if the buffer tank is completely sealed, the vacuum pump 9 may not be able to continuously extract gas due to air pressure problems. If the buffer tank is connected to the atmosphere, the separation device 2, the gas flow channel 12 of the heating device 1, etc. may be directly connected to the atmosphere, which may pose a risk of radioactive leakage. For this reason, two buffer tank structures are provided in this embodiment.

Specifically, when the vacuum pump 9 is turned on and the height of the condensate in the first buffer tank 941 is lower than the 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, the second valve 944 can be closed and the first valve 943 can be opened to allow the condensate in the first buffer tank 941 to enter the second buffer tank 942, thereby releasing the pressure in the first buffer tank 941.

After all the condensate in the first buffer tank 941 enters 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. Thus, when more condensate accumulates 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.

In this embodiment, the first valve 943 and the second valve 944 will not be opened at the same time, thereby ensuring that the vacuum pump 9 can continuously extract gas and that the separation device 2, the gas flow channel 12, etc. will not be directly connected to the atmospheric environment.

In some embodiments, the second buffer tank 942 may be connected to the condensate recovery device 62, and a third valve 945 is provided at the connection between the second buffer tank 942 and the condensate recovery device 62. In this embodiment, after the condensate in the first buffer tank 941 enters the second buffer tank 9421, the first valve 943 may be closed and the second valve 944 and the third valve 945 may be opened to introduce the condensate in the second buffer tank 942 into the condensate recovery device 62.

In some embodiments, the vacuum pump 9 can be connected to a filter device 95, which can be connected to 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.

In some embodiments, the exhaust pipe 96 can be configured as a segmented structure, and the segments can be removed from each other or slide relative to each other. Thus, when no radioactive liquid waste treatment is being performed, the segments of the exhaust pipe 96 can be removed or folded together to avoid limited movement due to its high height.

In some embodiments, referring to Figures 9 and 10, the radioactive liquid waste treatment system further comprises a support platform 100, which can be placed horizontally, and the above-mentioned device can be fixed on the support platform 100. In this embodiment, the above-mentioned device is fixed on the same horizontal plane, thereby reducing the height of the radioactive liquid waste treatment system in the vertical plane, making the overall structure of the radioactive liquid waste treatment system more compact, and convenient for arrangement in a relatively narrow space.

In some embodiments, the support platform 100 can be fixed on a movable platform, so that the entire radioactive waste treatment system is movable, so that its application scenario does not have to be limited to the factory building. The movable platform can be a car, and is equipped with a carriage, and the support platform 100 and the above-mentioned devices can be fixed in the carriage. As described above, the various devices in the radioactive waste treatment system in this embodiment are fixed on the same horizontal plane, so that the radioactive waste treatment system of this embodiment as a whole can meet the height limit requirements when the vehicle is driving, so that it can freely drive on the road to the required location for radioactive waste treatment.

In some embodiments, the liquid flow channel 11 and the 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 the gas flow channel 12 are long enough and can meet the height requirements.

In some embodiments, the feeding device 5 , the heating device 1 , the separation device 2 , and the steam compression device 4 may be arranged sequentially along the first direction of the supporting platform 100 .

Further, in some embodiments, the steam generating device 6 and the steam compressing device 4 may be arranged side by side along the second direction of the supporting platform 100 .

It can be understood that compared with the feeding device 5, the heating device 1, and the separation device 2, the radioactivity content in the steam compression device 4 and the steam generating device 6 is lower. Therefore, the steam compression device 4 and the steam generating device 6 are arranged side by side and on one side of the above three devices, so that the entire radioactive waste liquid treatment system is divided into high-radioactivity and low-radioactivity areas, which is convenient for ensuring the safety of operators.

In some embodiments, the radioactive liquid waste treatment system may include a partition, which may extend along the second direction, and the steam generator 4 and the steam compression device 6 are arranged on the side of the partition away from the separation device 2. In this embodiment, the partition is further used to isolate low-radioactive devices such as the steam generator 4 and the steam compression device 6 from high-radioactive devices to ensure safety. As described above, the support platform 100 and the above-mentioned devices can be arranged in a carriage, and the partition can be sealed and connected to the carriage, so that the steam generator 4, the steam compression device 6 and other low-radioactive devices and the high-radioactive devices are in two relatively sealed partitions.

In some embodiments, the condensate recovery device 62 may be disposed on a side of the steam compression device 4 facing away from the separation device 2 , that is, it is also disposed in the partition where the low-radioactivity device is located.

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

In some embodiments, some devices without control devices and electrical equipment, such as electrical cabinets for providing power to the above-mentioned devices, and controllers for controlling the startup and operation of the above-mentioned devices and monitoring the operating parameters of the above-mentioned devices, etc., can also be set on the above-mentioned support platform 100. Since these devices are not radioactive, they can be set on the side of the steam generating device 4, the steam compression device 6, the condensate recovery device 62 and other devices away from the separation device 2, and can also be isolated from the above-mentioned devices by means of partitions. Thus, the entire radioactive waste liquid treatment system is divided into three areas: high radiation area, low radiation area and non-radiation area.

As described above, there are multiple pipelines between the above-mentioned multiple devices, some pipelines are used for transferring condensate, and some pipelines are used for extracting and transferring gas. In some embodiments, these pipelines for transferring condensate can be set along the surface of the support platform 100, and the pipelines for extracting and transferring gas can be set along the top surface of each of the above-mentioned devices.

In some embodiments, referring to FIG10 , the support platform 100 includes a support plate 110 and a support frame 120. The support frame 120 is disposed above the support plate 110 and a gap is formed between the support frame 120 and the support plate 110. In this embodiment, the above-mentioned various devices may be connected to the support frame 120. It can be understood that liquid leakage may occur during the operation of the above-mentioned various devices. 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 around.

In some embodiments, a side of the support plate 110 facing the support frame 120 is formed with an inclination angle. Therefore, the liquid leaking into the gap will flow along the inclination angle to a corner of the support plate 110, which is convenient for collecting the leaked liquid.

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

The embodiments of the present application also provide a method for treating radioactive liquid waste, which can be applied to the radioactive liquid waste treatment system described in one or more of the embodiments above.

Specifically, the radioactive waste treatment method includes:

S1: The radioactive waste liquid is driven to circulate between the heating device and the separation device by means of a circulation pump, wherein the heating device is used to heat the radioactive waste liquid to make the radioactive waste liquid boil in the separation device, and the separation device is used to separate the steam generated when the radioactive waste liquid boils to concentrate the radioactive waste liquid. A pressure reducing valve is provided between the heating device and the separation device, and the pressure reducing valve reduces the pressure of the radioactive waste liquid in the heating device after it enters the separation device.

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

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

As described above, in the method provided in this embodiment, a pressure reducing valve is used to reduce the pressure of the radioactive waste liquid after it enters the separation device, thereby ensuring that the radioactive waste liquid entering the separation device boils and further improving the utilization rate of the heat source of the heating device, thereby indirectly reducing the energy consumption during the treatment of the radioactive waste liquid.

In some embodiments, the method further comprises: adjusting the opening of the pressure reducing valve so that the radioactive waste liquid does not evaporate in the heating device but evaporates after entering the separation device. In this embodiment, by adjusting the opening of the pressure reducing valve, it is possible to ensure that the radioactive waste liquid in the liquid flow channel does not boil, thereby improving the utilization rate of the heat source and reducing energy consumption.

In some embodiments, steam generated by a steam generating device may be introduced into the heating device as a second heat source of the heating device.

In some embodiments, the condensate in the heating device can be introduced into the steam generating device as a water source for the steam generating device. The condensate is generated after the compressed steam in the heating device exchanges heat with the radioactive waste liquid. It can be understood that there is still a large amount of residual heat in the condensate. In this embodiment, the condensate is introduced into the steam generating device as a water source, so that the residual heat in the condensate can be fully utilized, thereby reducing the energy required for the steam generating device to generate steam, thereby reducing the energy consumption when treating the radioactive waste liquid.

In some embodiments, a discharge port is provided on the circulation pipeline between the heating device and the separation device, and leading the concentrated radioactive waste liquid out of the separation device and the heating device may include: after determining that the radioactive waste liquid has been concentrated to a predetermined multiple, opening the discharge port to continuously lead the radioactive waste liquid out of the separation device and the heating device.

In some embodiments, a discharge port is provided on the circulation pipeline between the heating device and the separation device, and leading the concentrated radioactive waste liquid out of the separation device and the heating device may include: after determining that the radioactive waste liquid has been concentrated to a predetermined multiple, opening the discharge port to lead the radioactive waste liquid out of the separation device and the heating device, and then closing the discharge port.

In some embodiments, during the circulation process, the radioactive waste liquid in the feeding device can be continuously introduced into the heating device.

In some embodiments, the rate of introducing the radioactive waste liquid from the supply device into the heating device can be adjusted based on the liquid level in the separation device to maintain the liquid level in the separation device at a working liquid level.

In some embodiments, introducing the radioactive waste liquid from the feeding device into the heating device may include: introducing the radioactive waste liquid from the feeding device into a preheating device for preheating treatment, and introducing the radioactive waste liquid in the preheating device into the heating device.

In some embodiments, introducing the radioactive waste liquid from the feeding device into the preheating device for preheating treatment may include: introducing the radioactive waste liquid from the feeding device into the preheating device, and introducing the condensate in the steam generating device into the preheating device for heat exchange with the radioactive waste liquid, so as to preheat the radioactive waste liquid.

In some embodiments, the condensate in the preheating device can be introduced into a condensate recovery device.

In some embodiments, before the steam separated by the separation device is introduced into the steam compression device, the steam separated by the separation device can be purified by means of a purification device.

In some embodiments, a negative pressure environment can be created in the separation device with the aid of a vacuum pump.

In some embodiments, constructing a negative pressure environment in the separation device by means of a vacuum pump may include: before starting to process the radioactive liquid waste, extracting gas in the separation device by means of a vacuum pump to construct a negative pressure environment in the separation device.

In some embodiments, constructing a negative pressure environment in the separation device with the aid of a vacuum pump may also include: during the circulation process, monitoring the pressure in the separation device, and if the pressure in the separation device is higher than the desired negative pressure, extracting the gas in the separation device with the aid of a vacuum pump to maintain the negative pressure environment in the separation device.

In some embodiments, the non-condensable gas in the heating device can be extracted with the aid of the vacuum pump.

In some embodiments, during the process of creating a negative pressure environment in a separation device and extracting non-condensable gas from a heating device with the help of a vacuum pump, the gas extracted by the vacuum pump can be cooled with the help of a cooling device to recover the vapor in the gas extracted by the vacuum pump as a condensate.

Some specific technical details of the above-mentioned radioactive waste liquid treatment method can be referred to the description of the relevant parts of the radioactive waste liquid treatment system above, and will not be repeated here.

The present invention is described in detail above with reference to the accompanying drawings and embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The contents not described in detail in the present invention can adopt the existing technology.

Claims (9)

1. A radioactive waste treatment system comprising:

A heating device formed with a liquid flow passage for flowing radioactive waste liquid, and a gas flow passage provided outside the liquid flow passage, the gas flowing in the gas flow passage being capable of exchanging heat with the radioactive waste liquid in the liquid flow passage to heat-treat the radioactive waste liquid;

a separation device in communication with the liquid flow channel for separating vapor from the boiled radioactive waste after the heat treatment to concentrate the radioactive waste;

A pressure reducing valve arranged between an outlet of the liquid flow channel and an inlet of the separation device, wherein the pressure reducing valve is used for reducing the pressure of the radioactive waste liquid in the heating device after the radioactive waste liquid enters the separation device;

A circulation line that communicates the separator with an inlet of the liquid flow passage;

a circulation pump provided in the circulation line, the circulation pump being for driving the radioactive waste liquid to circulate between the heating device and the separation device via the circulation line;

a vapor compression device arranged between the separation device and an inlet of the gas flow passage, wherein the vapor compression device is used for compressing and heating vapor separated by the separation device to obtain compressed vapor and introducing the compressed vapor into the gas flow passage to serve as a first heat source of the heating device;

the feeding device is used for introducing the radioactive waste liquid into the liquid flow channel of the heating device;

The discharging port is arranged in the circulating pipeline and is used for leading out the concentrated radioactive waste liquid;

The steam generation device is communicated with the inlet of the gas flow passage, so that steam generated by the steam generation device can enter the gas flow passage to serve as a second heat source of the heating device;

The radioactive waste liquid treatment system further comprises a support platform, wherein the support platform is arranged to be horizontally placed, and the radioactive waste liquid treatment system of the device is fixed on the support platform;

The liquid flow channel and the gas flow channel of the heating device are arranged in parallel with the supporting platform;

the feeding device, the heating device, the separating device and the vapor compression device are arranged in sequence along a first direction of the supporting platform;

the steam generating device and the steam compression device are arranged side by side along the second direction of the supporting platform;

the steam generating device and the steam compressing device are arranged on one side of the feeding device, the heating device and the separating device;

The radioactive waste liquid treatment system includes a partition plate disposed to extend in a second direction, the vapor generating device and the vapor compression device being disposed on a side of the partition plate facing away from the separation device.

2. The system of claim 1, wherein the gas flow passage communicates with an inlet of the steam generation device to enable condensate in the gas flow passage to be used as a water source for the steam generation device, the condensate being generated after heat exchange of gas in the heating device with the radioactive waste liquid.

3. The system of claim 2, further comprising:

and the preheating device is arranged between the feeding device and the heating device and is used for preheating the radioactive waste liquid which is introduced into the liquid flow channel from the feeding device.

4. A system according to claim 3, wherein the steam generator is in communication with the pre-heater, such that condensate in the steam generator can enter the pre-heater as a heat source for the pre-heater.

5. The system of claim 4, further comprising:

and the condensate recovery device is communicated with the preheating device and is used for recovering the condensate in the preheating device.

6. The system of claim 1, further comprising:

And the purification device is arranged between the separation device and the vapor compression device and is used for purifying the vapor separated by the separation device before the vapor enters the vapor compression device.

7. The system of claim 1, further comprising:

and the vacuum pump is communicated with the separation device and is used for pumping gas in the separation device so as to build a negative pressure environment in the separation device.

8. The system of claim 7, wherein the vacuum pump is further configured to pump non-condensable gases in the heating device.

9. The system of claim 8, further comprising:

And the cooling device is arranged on a passage between the vacuum pump and the separation device and is used for cooling the gas pumped by the vacuum pump so as to recover steam in the gas pumped by the vacuum pump as condensate.