CN115966329A

CN115966329A - Radioactive waste liquid treatment method and system

Info

Publication number: CN115966329A
Application number: CN202310007642.3A
Authority: CN
Inventors: 鄢枭; 赵大鹏; 张志良; 韩一丹; 穆建波; 马聪聪
Original assignee: China Institute of Atomic of Energy
Current assignee: China Institute of Atomic of Energy
Priority date: 2023-01-04
Filing date: 2023-01-04
Publication date: 2023-04-14

Abstract

The embodiment of the application provides a radioactive liquid waste treatment method, which comprises the following steps: driving the radioactive waste liquid to circulate between a heating device and a separating device by a circulating pump, wherein the heating device is used for heating the radioactive waste liquid so as to evaporate the radioactive waste liquid in the separating device, the separating device is used for separating steam generated when the radioactive waste liquid is evaporated so as to concentrate the radioactive waste liquid, and a negative pressure environment is arranged in the separating device; in the circulating process, the vapor separated by the separation device is compressed and heated by the vapor compression device to obtain compressed vapor, and the compressed vapor is introduced into the heating device to be used 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 the predetermined factor, the radioactive waste liquid is led out of the heating device and the separating device. The embodiment of the application also provides a radioactive liquid waste treatment system.

Description

Radioactive waste liquid treatment method and system

Technical Field

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

Background

In the nuclear technology-related process engineering, a large amount of radioactive waste liquid is often generated, the radioactive waste liquid needs to be concentrated, the concentration of the radioactive waste liquid is usually completed by adopting an evaporation mode, however, the process flow of the radioactive waste liquid treatment adopted in the related technology has higher energy consumption.

Disclosure of Invention

In order to solve at least one technical problem in the prior art and other aspects, the present application provides a radioactive liquid waste treatment method and system.

According to a first aspect of embodiments of the present application, there is provided a radioactive liquid waste treatment method including: driving the radioactive waste liquid to circulate between a heating device and a separating device by a circulating pump, wherein the heating device is used for heating the radioactive waste liquid so as to evaporate the radioactive waste liquid in the separating device, the separating device is used for separating steam generated in the evaporation of the radioactive waste liquid so as to concentrate the radioactive waste liquid, and a negative pressure environment is arranged in the separating device; in the circulating process, the vapor separated by the separation device is compressed by the vapor compression device to raise the temperature to obtain compressed vapor, and the compressed vapor is introduced into the heating device to be used 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 the predetermined factor, the radioactive waste liquid is led out of the heating device and the separating device.

According to a second aspect of embodiments of the present application, there is provided a radioactive liquid waste treatment system comprising: the heating device is provided with a liquid flow channel for flowing the radioactive waste liquid and a gas flow channel arranged outside the liquid flow channel, and gas flowing in the gas flow channel can exchange heat with the radioactive waste liquid in the liquid flow channel so as to heat the radioactive waste liquid; a separation device for separating steam from the radioactive waste liquid after the heating treatment to concentrate the radioactive waste liquid; the circulating pipeline is used for communicating the separating device with the inlet of the liquid flow channel; the circulating pump is arranged in the circulating pipeline and is used for driving the radioactive waste liquid to circularly flow between the heating device and the separation device through the circulating pipeline; the vapor compression device is arranged between the separation device and the inlet of the gas flow passage and is used for compressing and heating the vapor separated by the separation device to obtain compressed vapor, and the compressed vapor can be introduced into the gas flow passage to serve as a first heat source of the heating device; the vacuum pump is communicated with the separation device and used for extracting gas in the separation device so as to establish a negative pressure environment in the separation device; the feeding device is communicated with the heating device and is used for introducing radioactive waste liquid into a liquid flow channel of the heating device; and the discharge port is arranged in the circulating pipeline and used for leading out the concentrated radioactive waste liquid.

The radioactive liquid waste treatment method and the system can obviously reduce energy consumption during the evaporation concentration treatment of the radioactive liquid waste.

Drawings

FIG. 1 is a schematic view of a radioactive waste treatment system according to one embodiment of the present application;

FIG. 2 is a schematic view of a radioactive liquid waste treatment system according to another embodiment of the present application;

FIG. 3 is a schematic view of a radioactive waste treatment system according to yet another embodiment of the present application;

FIG. 4 is a schematic view of a radioactive waste treatment system according to yet another embodiment of the present application;

FIG. 5 is a schematic view of a radioactive waste treatment system according to yet another embodiment of the present application;

FIG. 6 is a schematic view of a radioactive waste treatment system according to yet another embodiment of the present application;

FIG. 7 is a schematic view of a radioactive waste treatment system according to yet another embodiment of the present application;

FIG. 8 is a schematic view of a surge tank according to an embodiment of the present application;

fig. 9 is a schematic layout of a radioactive waste treatment system according to an embodiment of the present application;

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

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below with reference to the accompanying drawings.

Embodiments of the present application first provide a radioactive liquid waste treatment system, and 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 vapor compression device 4, and a supply device 5.

The heating device 1 is used for heating the radioactive waste liquid so that the radioactive waste liquid can reach a boiling temperature. The heating apparatus 1 may be a heat exchanger, for example, the heating apparatus 1 may be formed with a liquid flow passage 11 for flowing the radioactive waste liquid, and a gas flow passage 12 disposed outside the liquid flow passage 11, and in the course of actually performing the radioactive waste liquid treatment, the gas flowing in the gas flow passage 12 may exchange heat with the radioactive waste liquid flowing in the liquid flow passage 11, thereby performing the heating treatment on the radioactive waste liquid. The liquid flow channel 11 and the gas flow channel 12 can be arranged in a specific manner by referring to a heat exchanger provided in the related art, and will not be described in detail herein.

The separation device 2 communicates with 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 be boiled in the separation device 2, and the vapor formed at the time of boiling is separated by the separation device 2, so that the radioactive waste liquid is concentrated. The separating device 2 may be formed with a cavity, and the top of the cavity may be formed with a gas outlet, and 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 boiling will leave the separating 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 communicated with the inlet of the liquid flow channel 11 through the circulating pipeline 31, the circulating pump 3 can be arranged on the circulating pipeline 31, when radioactive waste liquid treatment is carried out, under the driving of the circulating pump 3, the residual radioactive waste liquid after concentration can return to the liquid flow channel 11 of the heating device 1, and the circulation flow between the heating device 1 and the separation device 2 is continued, so that the concentration process is repeated.

The vapor compression device 4 is disposed between the separation device 2 and the inlet of the gas flow passage 12, and is capable of compressing and heating the vapor separated by the separation device 2 and introducing it into the gas flow passage of the heating device 1, thereby serving as a heat source of the heating device 1.

It can be understood that there is still a large amount of residual heat in the steam separated by the separation device 2, but the residual heat is not enough to heat the radioactive waste liquid to boiling, and the steam compression device 4 can compress the steam separated by the separation device 2 to make it have the ability to heat the radioactive waste liquid to boiling again, so that the residual heat in the steam separated by the separation device 2 can be fully recycled, and the energy consumption in the radioactive waste liquid treatment process can be indirectly reduced.

The heating apparatus 1 may be provided with a plurality of heat sources, that is, in addition to the compressed vapor generated by the vapor compression device 4, another heat source may be provided, and the other heat source may be hot vapor generated by another apparatus, or some heating means or the like provided in the heating apparatus 1, and the other heat source may be used as a supplement or a substitute for the compressed vapor to supply the heat required for the evaporation of the radioactive waste liquid, for example, when the radioactive waste liquid treatment is initially started, the amount of the compressed vapor is small or even the compressed vapor is not present, and the radioactive waste liquid may be heated by using another heat source.

The supply means 5 communicates with the liquid flow channel 11 of the heating device 1, so that radioactive waste liquid is introduced into the heating device 1. In some embodiments, the supply device 5 may be in communication with the circulation line 31, i.e. indirectly with the liquid channel 11 by means of the circulation line 31. In some other embodiments, the supply means 5 may also communicate directly with the liquid channel 11 without the aid of the circulation line 31. The feeding device 5 may be provided with a feeding pump to provide motive force for the radioactive waste liquid.

In the actual process of radioactive waste liquid treatment, the radioactive waste liquid in the feeding device 5 may be continuously introduced into the liquid channel 11 at a certain rate, or may be stopped after a certain amount of radioactive waste liquid is introduced, and the radioactive waste liquid in the next batch is introduced after the radioactive waste liquid that has been introduced is concentrated and extracted, which is not limited in this respect. It will be appreciated that in the continuous feed embodiment, the operation is simpler, but it may be difficult to more accurately control the multiple at which the radioactive waste is concentrated. The batch feeding can accurately control the concentration multiple of the radioactive waste liquid, but requires frequent operation of operators.

The circulation line 31 may be provided with a discharge port 32, and after the radioactive waste liquid has been concentrated by a desired multiple, the radioactive waste liquid after the concentration may be discharged through the discharge port 32.

During actual radioactive waste treatment, a sample may be taken at the discharge port 32 to determine whether the radioactive waste has been concentrated to a desired multiple, and/or the time required for the concentration to the desired multiple may be calculated from the actual treatment efficiency of the radioactive waste treatment system, from which it is determined whether the radioactive waste has been concentrated to the desired multiple. When the feeding device 5 continuously introduces the radioactive waste liquid, the discharge port 32 may be opened after the radioactive waste liquid has been concentrated by a desired factor and the radioactive waste liquid may be continuously withdrawn at a certain rate. When the feeding device 5 only introduces a certain amount of radioactive waste liquid, the discharge port 32 may be opened after the radioactive waste liquid has been concentrated by a desired factor to discharge the radioactive waste liquid entirely. Those skilled in the art can set the setting according to actual situations, and details are not described herein.

In some embodiments, referring to fig. 1, a pressure reducing valve 21 may be disposed between the outlet of the liquid channel 11 of the heating device 1 and the inlet of the separation device 2, and the pressure reducing valve 21 may reduce the pressure of the radioactive waste liquid in the heating device 1 after entering the separation device 2.

The pressure reducing valve 21 may be any suitable pressure reducing valve provided in the related art, and is not limited thereto. The pressure reducing valve 21 is capable of creating a pressure difference between the liquid channel 11 and the separation device 2, thereby causing a pressure reduction after the radioactive waste liquid in the liquid channel 11 enters the separation device 2.

It will be appreciated that the boiling point of the liquid is pressure dependent and will drop as the pressure drops, thereby ensuring boiling of the radioactive waste liquid entering the separation device 2 by means of the pressure reducing valve 21 and further increasing the availability of the heat source of the heating device 1, thereby indirectly reducing the energy consumption of the radioactive waste liquid treatment system.

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

In some embodiments, referring to fig. 2, the radioactive liquid waste treatment system may further include a steam generation device 6, and the steam generation device 6 is communicated with an inlet of the gas flow channel 12, so that steam generated by the steam generation device 6 can enter the gas flow channel 12 to serve as a second heat source of the heating device 1. The steam generator 6 may be any suitable device capable of generating steam by heating and vaporizing water, and is not limited thereto.

In this embodiment, the steam generating device 6 can be used as a second heat source for the heating device 1 to supplement the compressed steam, so that the compressed steam can be used as a heat source for the heating device 1 when it is not yet generated, or used as a heat source for the heating device 1 together with the compressed steam during the treatment process, as described above.

In some embodiments, the heating device 1 may be configured with other heat sources besides the steam generating device 6, which are not described herein.

It is understood that in the above embodiment, the heating efficiency of the heating device 1 is actually controlled by the operating parameters of the vapor compression device 4 and the vapor generation device 6, and during the actual radioactive liquid waste treatment, the heating efficiency of the heating device 1 can be adjusted by adjusting either one of the two.

In some embodiments, it is understood that the vapor in the gas channel 12 will condense to form a liquid after heat exchange with the radioactive waste, and the gas channel 12 can be in communication with the inlet of the vapor generation device 6, such that the condensate in the gas channel 12 can enter the vapor generation device 6 to serve as a water source for the vapor generation device 6. In addition to the condensate, the steam generating device 6 may also have another water source to ensure that the steam generating device 6 is able to continuously generate a sufficient amount of steam.

It can be understood that a large amount of residual heat still exists in the condensate, and in the embodiment, the condensate is introduced into the steam generation device 6 to serve as a water source, so that the residual heat in the condensate can be fully utilized, the energy required by the steam generation device 6 for generating steam is reduced, and the energy consumption of the radioactive waste liquid treatment system is further reduced.

In some embodiments, the steam generating device 6 may be arranged below the heating device 1, such that 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 locate the steam generating device 6 at the same level as the heating device 1 to reduce the height of the entire radioactive liquid disposal system, and at this time, it may be necessary to pump the condensate in the heating device 1 to the steam generating device 6 by means of the condensate pump 61.

In particular, the condensate pump 61 may be connected at the bottom of the gas channel 12 of the heating device 1, such that condensate deposited at the bottom of the gas channel 12 will be pumped into the steam generating device 6.

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

In some embodiments, the radioactive liquid waste treatment system may further include a preheating device 7, and the preheating device 7 may be disposed between the supply device 5 and the heating device 1, and may preheat the radioactive liquid waste entering the liquid flow path 11 from the supply device 5. It will be appreciated that the radioactive waste liquid may not be sufficiently heated to the boiling temperature in the liquid flow path 11 for the limited time in one cycle, and for this reason, the radioactive waste liquid is preheated in this embodiment to increase the efficiency of the radioactive waste liquid. The preheating device 7 may be a heat exchanger, or other devices with heat exchange or heating functions, which is not limited in this respect.

In some embodiments, the steam generating device 6 may be in communication with the preheating device 7, such that condensate in the steam generating device 6 can enter the preheating device 7 to act as a heat source for the preheating device 7. Specifically, two liquid flow passages may be formed in the preheating device 7, and the condensate and the radioactive waste liquid may flow in the two liquid flow passages, respectively, so that the condensate and the radioactive waste liquid exchange heat.

As described above, there is residual heat energy in the condensate, and the condensate is used as the heat source for preheating in the present embodiment, so that the residual heat energy is more fully utilized, and the energy consumption of the radioactive waste liquid treatment system is reduced.

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

It will be appreciated that if too great a flow of condensate is introduced into the preheating device 7, this may result in too low a water level in the steam generating device 6, which in turn may result in insufficient steam being 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, 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 preset water level, the preheated temperature may be increased by reducing the rate of introduction of the radioactive waste liquid from the supply device 5 to the preheating device 7.

In some embodiments, the radioactive liquid waste treatment system further comprises a condensate recovery device 62, and the condensate recovery device 62 may be in communication with the preheating device 7, thereby recovering the condensate in the preheating device 7.

In some embodiments, referring to fig. 3, the steam generated by the steam generating device 6 may also be introduced to the inlet of the steam compression device 4. It will be appreciated that a compressor is provided in the vapour compression device 4 and that surge may occur when the flow rate of the compressor is reduced or when the pressure difference between the inlet and the outlet is large, which may have a severe effect on the performance or the service life of the vapour compression device 4. In the embodiment, the steam generated by the steam generator 6 is also introduced into the inlet of the steam compressor 4, so that the steam can be supplemented when the flow of the steam separated by the separator 2 is small, the flow of the steam at the inlet of the steam compressor 4 is ensured, and the surge condition is avoided.

In some embodiments, an air compensating valve may be disposed in the path between the vapor compression device 4 and the vapor generation device 6, and during the actual radioactive liquid waste treatment, the operating current of the vapor compression device 4 may be monitored, and when the variation of the operating current of the vapor compression device 4 is greater than a preset threshold, i.e., when abnormal fluctuation occurs, the air compensating valve is opened to introduce the vapor of the vapor generation device 6 to the inlet of the vapor compression device 4, so as to avoid surge. In some other embodiments, it may also be determined whether the aeration valve needs to be opened for aeration by monitoring the pressure at the inlet of the vapor compression device 4, the flow of gas, etc.

Further, when the flow rate of the steam at the inlet of the steam compression device 4 is decreased, it means that the heating device 1 is operated less efficiently, resulting in a lower flow rate of the steam separated by the separation device 2. At this time, as described above, the vapor flow rate can be adjusted by controlling the efficiency of concentrating the radioactive waste liquid by adjusting the operation parameters of the vapor compression device 4 and/or the vapor generation device 6.

For example, the rotational speed of the vapour compression device 4 may be increased when the vapour flow at the inlet of the vapour compression device 4 is decreased. Alternatively, the power of the steam generating device 6 may be increased when the steam flow at the inlet of the steam compressing device 4 is decreased. As the flow of vapor at the inlet of the vapor compression device 4 increases, the rotational speed of the vapor compression device 4 may be reduced. Alternatively, the power of the steam generating device 6 may be reduced when the steam flow at the inlet of the steam compressing device 4 is increased.

In some embodiments, the gas pressure in the separation device 2 may be detected when the steam flow at the inlet of the steam compression device 4 is reduced, the rotational speed of the steam compression device 4 may be increased if the gas pressure in the separation device 2 is higher than a preset pressure, and the power of the steam generation device 6 may be increased if the gas pressure in the separation device 2 is lower than the preset pressure. In this embodiment, the effectiveness of the control is improved by selecting which of the apparatus parameters is specifically adjusted by means of the gas pressure in the separation apparatus 2.

In some embodiments, the condensate in the steam generator 6 may be further introduced to the outlet of the steam compressor 4 to perform a certain spraying temperature reduction treatment on the compressed steam. It will be appreciated that the compressed steam may be compressed into superheated steam, which has a lower pressure than saturated steam, but the superheated steam does not significantly improve the working efficiency of the heating device 1, and for this reason, the compressed steam is subjected to a certain spraying process so as not to form superheated steam, thereby avoiding surging 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 vapor compression device and the vapor temperature of the sprayed compressed vapor are monitored, and the amount of condensate sprayed on the compressed vapor is increased if the vapor temperature is greater than the saturated vapor temperature at the current pressure at the outlet of the vapor compression device. If the steam temperature is lower than the saturated steam temperature under the current pressure, the amount of condensate to be sprayed is reduced, or spraying is not performed, so that the working efficiency of the heating device 1 is prevented from being affected by excessive spraying treatment.

In some embodiments, it may be desirable to control the liquid level in the separation device 2 so that the radioactive waste boils at the appropriate liquid level for better separation. For example, the liquid level in the separation device 2 can be adjusted by adjusting the power of the circulation pump 3, or the liquid level in the separation device 2 can also be adjusted by adjusting the feed efficiency of the feed device 5.

In some embodiments, the rate of introduction of exothermic waste liquid from the feed device 5 into the heating device 1 may be reduced as the liquid level in the separation device 2 increases. When the liquid level in the separation device 2 decreases, the rate of introduction of radioactive waste from the feeding device 5 into the heating device 1 may be increased.

In some embodiments, referring to fig. 4, the supply device 5 may be provided with a first pipeline 51 communicated with the heating device 1, the first pipeline 51 is used for introducing the radioactive waste liquid into the heating device 1, a second pipeline 52 communicated with the supply device 5 is arranged on the first pipeline 51, and the second pipeline 52 is used for returning part of the radioactive waste liquid in the first pipeline 51 to the supply device 5. As an example, a valve may be provided on the second pipe 52, and the opening of the valve may be adjusted to adjust the rate of the radioactive waste liquid returned to the supply device 5.

Compared with directly adjusting the flow rate in the first pipeline 51, the adjustment method provided by 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.

In some embodiments, referring to fig. 5, the radioactive liquid waste treatment system may further include a purification apparatus 8 disposed between the separation apparatus 2 and the vapor compression apparatus 4, the purification apparatus 8 being configured to purify the vapor separated by the separation apparatus 2 before it enters the vapor compression apparatus 4. As described above, the main component of the steam separated by the separation device 2 is water, the steam will be subsequently turned into condensate and recovered, and some radioactive substances may be entrained in the steam, so that the purification device 8 is provided in this embodiment to purify the steam so as to remove the radioactive substances entrained in the steam and avoid the radioactive content of the condensate from exceeding the standard.

The skilled person can specifically set the purification mode of the purification device 8 according to actual needs, for example, a spray nozzle may be provided in the purification device 8, and may perform a spraying process on the steam entering the purification device 8 to remove the radioactive substances entrained therein. Alternatively, the purification apparatus 8 may be provided with a structure having a filtering function, such as a mesh or a packing, which can filter and adsorb the radioactive substances entrained in the vapor.

In some embodiments, a structure with a filtering function, such as a wire mesh, a packing, etc., may also be disposed on the top of the separation device 2, which can perform a certain pre-purification on the steam before entering the purification device 8, further improving the purification effect.

In some embodiments, as described above, the purification device 8 may be provided with a spray head 81, and the spray head 81 may perform a spraying process on the steam entering the purification device 8. It will be appreciated that the temperature of the liquid used in the spraying process must not be too low to avoid condensing a significant amount of the steam and resulting in waste of heat. For this purpose, in some embodiments, the condensed water in the steam generating device 6 may be introduced into the purification device 8 as shower water, which, as described above, has a heat residual that can avoid condensing a large amount of steam while the shower process is being performed.

The spray water remaining after the spray treatment may be entrained with more radioactive substances, and for this reason, in some embodiments, the spray-treated spray water may be introduced into the supply device 5 to avoid radioactive leakage.

In some embodiments, referring to fig. 6, the spraying water dropping on the bottom of the purification apparatus 8 after the spraying treatment can be reintroduced into the spray head 81 for spraying, thereby avoiding introducing too much condensed water into the spray head 81 for the spraying treatment, and further reducing the waste of heat.

In this embodiment, the shower water at the bottom of the purification apparatus 8 may be introduced into the supply apparatus 5 at predetermined intervals. Further, after the liquid at the bottom of the purification apparatus 8 is introduced into the supply apparatus, the condensate in the steam generation apparatus 6 may be introduced into the spray head 81 to replenish the liquid for the spray treatment.

It will be appreciated that during the circulation of the spray liquid, there may be some condensation of the vapour which causes the spray liquid to rise in height, which in turn affects the purification efficiency, and for this purpose, in some embodiments, it is also possible to monitor the pressure difference between the inlet and the outlet of the purification device 8, and when this pressure difference is greater than a preset pressure difference, it is possible to introduce some of said condensate at the bottom of the purification device 8 into the feed device 5, thus ensuring that the purification device 8 always has a high purification efficiency.

In some embodiments, referring to fig. 7, the radioactive liquid waste treatment system may further comprise a vacuum pump 9, the vacuum pump 9 being in communication with the separation device 2 for drawing gas from the separation device 2 to create a negative pressure environment in the separation device 2. It will be appreciated that the creation of a sub-atmospheric environment within the separation device 2 helps to further enhance the efficiency of the boiling of the radioactive waste liquid within the separation device 2.

In some embodiments, a first pumping hole 91 may be disposed at an outlet of the separation device 2, a second pumping hole 92 may be disposed on the gas flow passage 12 of the heating device 1, and the vacuum pump 9 may pump gas from the first pumping hole 91 and/or the second pumping hole 92 to construct a negative pressure environment. The provision of the first suction port 91 and the second suction port 92 in the present embodiment contributes to an improvement in efficiency in constructing a negative pressure environment.

In some embodiments, establishing a negative pressure environment may be performed prior to introducing the radioactive waste. In some embodiments, the gas pressure in the separation device 2 may also be monitored during the radioactive liquid waste treatment, and if the gas pressure is higher than the desired negative pressure, a certain amount of gas may be extracted from the extraction opening to maintain the negative pressure environment.

In some embodiments, the vacuum pump 9 may also be used to extract non-condensable gases in the heating device 1. As described above, the gas introduced into the heating apparatus 1 is condensed into condensed water after heat exchange, however, some non-condensable gas, that is, non-condensable gas may be mixed into the heating apparatus 1, and when a large amount of non-condensable gas is accumulated in the heating apparatus 1, the overall temperature of the gas in the heating apparatus 1 is lowered, thereby affecting the heating efficiency of the heating apparatus 1, and for this reason, the non-condensable gas in the heating apparatus 1 may be extracted by the vacuum pump 9, thereby preventing accumulation of the non-condensable gas. Specifically, the non-condensable gasses may be extracted from the second air extraction ports 92.

In some embodiments, the non-condensable gas may be extracted once every predetermined time, or the temperature of the feed liquid in the separation device 2 may be monitored, which means that the heating efficiency is reduced if the temperature of the feed liquid in the separation device 2 is lower than the evaporation temperature, at which time the vacuum pump 9 may be turned on to extract the non-condensable gas in the heating device 1.

It will be appreciated that the extracted gas, whether in the construction of a negative pressure environment or in the extraction of non-condensable gases, contains a significant amount of vapour which may condense in the vacuum pump 9, thereby affecting the operating efficiency and lifetime of the vacuum pump 9, and for this reason, in some embodiments, the radioactive liquid waste treatment system may further comprise a cooling device 93 disposed in the passage between the vacuum pump 9 and the separation device 2, the cooling device 93 being configured to cool the gas extracted by the vacuum pump 9 to recover the vapour in the gas extracted by the vacuum pump 9 as a condensate.

In some embodiments, it is understood that when the vacuum pump 9 is powered more, it is possible to draw off some of the condensate in the cooling device 93, for which purpose, with reference to fig. 8, a buffer tank 94 may be provided between the vacuum pump 9 and the cooling device 93, the buffer tank 94 being used to store the condensate, avoiding it being drawn 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, a second valve 944, the first buffer tank 941 being in communication with the vacuum pump 9 and the cooling device 93, the second buffer tank 942 being disposed below the first buffer tank 941, the first valve 943 being disposed at a connection of the first buffer tank 941 and the second buffer tank 942, the second valve 944 being disposed to communicate the second buffer tank 942 with the atmosphere.

It can be understood that, during the process of performing the air extraction, if the buffer tank is completely sealed, the vacuum pump 9 may not be able to continuously extract the air due to the air pressure problem, and if the buffer tank is communicated with the atmosphere, the separation device 2, the gas flow passage 12 of the heating device 1, and the like may be directly communicated with the atmosphere, which may have a risk of radioactive leakage, and for this reason, two buffer tank structures are provided in the present embodiment.

Specifically, when the vacuum pump 9 is turned on and the condensate level in the first buffer tank 941 is lower than a preset value, the first valve 943 may be closed. When the height of the condensate in the first buffer tank 941 is higher than the predetermined value, which means that the pressure in the first buffer tank 941 is higher, 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, so as to release 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, so that 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 are not opened simultaneously, so that the vacuum pump 9 can continuously pump gas, and the separation device 2, the gas channel 12, and the like are not directly communicated with the atmosphere.

In some embodiments, the second buffer tank 942 may be in communication with the condensate recovery device 62, and a third valve 945 is provided where the second buffer tank 942 is in communication with 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 to the condensate recovery device 62.

In some embodiments, the vacuum pump 9 may be connected to a filtering device 95, the filtering device 95 may be connected to an exhaust pipe 96, the filtering device 95 may be used to filter radioactive materials in the gas extracted by the vacuum pump 9, and the exhaust pipe 96 may be used to exhaust the filtered gas.

In some embodiments, the vent tube 96 may be provided as a segmented structure, with the segments being removable from one another or slidable relative to one another, such that, without radioactive waste treatment, the segments of the vent tube 96 may be removed or folded over one another to avoid being tall and restricted in movement.

In some embodiments, referring to fig. 9 and 10, the radioactive waste treatment system further comprises a support platform 100, wherein the support platform 100 can be horizontally disposed, and the device can be fixed on the support platform 100. In this embodiment, above-mentioned device is fixed on same horizontal plane to, reduced the height of radioactive liquid waste treatment system in vertical plane, made radioactive liquid waste treatment system's overall structure compacter, the convenience is arranged in comparatively narrow and small space.

In some embodiments, the support platform 100 may be fixed to a movable platform, so that the entire radioactive waste disposal system is movable, and the application scenario is not necessarily limited to a factory. The movable platform may be a car and be provided with a carriage in which the support platform 100 and the above-mentioned devices may be fixed. As described above, the radioactive liquid waste treatment system of the present embodiment is configured such that the devices are fixed on the same horizontal plane, so that the radioactive liquid waste treatment system of the present embodiment can satisfy the height limit requirement when the vehicle is running, and thus, can run freely on the road to a desired position for radioactive liquid waste treatment.

In some embodiments, the liquid flow channels 11 and the gas flow channels 12 of the heating device 1 described above are arranged parallel to the support platform 100. That is, the heating device 1 is designed in a horizontal type, thereby ensuring that the liquid flow passage 11 and the gas flow passage 12 are long enough to meet the height requirement.

In some embodiments, the supply device 5, the heating device 1, the separation device 2, and the vapor compression device 4 may be sequentially disposed along the first direction of the support platform 100.

Further, in some embodiments, the vapor generation device 6 and the vapor compression device 4 may be positioned side-by-side along the second direction of the support platform 100.

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

In some embodiments, the radioactive liquid waste treatment system may comprise a partition, which may extend in the second direction, the steam generating means 4 and the steam compressing means 6 being arranged on a side of the partition facing away from the separating means 2. In this embodiment, the low-level radioactive devices such as the vapor generation device 4 and the vapor compression device 6 are isolated from the high-level radioactive devices by the partition plates, thereby ensuring safety. As described above, the support platform 100 and the above-described devices may be disposed in a vehicle cabin, and the partition may be sealingly connected to the vehicle cabin, such that the low-level and high-level radioactive devices, such as the vapor generation device 4 and the vapor compression device 6, are in two relatively sealed compartments.

In some embodiments, the condensate recovery device 62 may be arranged on the side of the vapour compression device 4 facing away from the separation device 2, i.e. it is also arranged in the zone in which the low-activity device is located.

In some embodiments, the circulation pump 3 and the purification apparatus 8 may be disposed at both sides of the heating apparatus 1 in the second direction of the support platform 100. In some embodiments, the preheating device 7 may be arranged between the feeding device 5 and the purification device 8.

In some embodiments, some devices without control equipment and electrical equipment, such as an electrical cabinet for providing power to the above devices, and a controller for controlling the start-up, operation, and monitoring the operation parameters of the above devices, may also be disposed on the support platform 100, and since these devices do not have radioactivity, they may be disposed on the side of the vapor generation device 4, the vapor compression device 6, the condensate recovery device 62, etc. facing away from the separation device 2, and may also be isolated from the above devices by means of partitions, so that the whole radioactive liquid waste treatment system is divided into three regions, i.e., a high-radioactivity region, a low-radioactivity region, and a non-radioactivity region.

As described above, there are a plurality of pipes between the devices, some for the transfer of condensate and some for the extraction and transfer of gas, and in some embodiments, the pipes for the transfer of condensate may be disposed along the surface of the support platform 100, and the pipes for the extraction and transfer of gas may be disposed along the top surface of each of the devices.

In some embodiments, referring to fig. 10, the support platform 100 includes a support plate 110 and a support bracket 120. The support bracket 120 is disposed above the support plate 110 and forms a gap with the support plate 110. In this embodiment, the above-mentioned devices may be connected to the supporting frame 120, and it is understood that liquid leakage may occur during the operation of the above-mentioned devices, and since a gap is formed between the supporting frame 120 and the supporting plate 110, the liquid leakage may be collected in the gap to prevent the liquid leakage from flowing around.

In some embodiments, a surface of the support plate 110 facing the support frame 120 is formed with an inclination angle. Thus, the liquid leaked into the gap will flow to a corner of the support plate 110 along the inclination angle, facilitating the collection of the leaked liquid.

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

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

Specifically, the radioactive waste liquid treatment method comprises the following steps:

s1: the radioactive waste liquid is driven to circulate between a heating device and a separating device by a circulating pump, wherein the heating device is used for heating the radioactive waste liquid so as to evaporate the radioactive waste liquid in the separating device, the separating device is used for separating steam generated when the radioactive waste liquid is evaporated so as to concentrate the radioactive waste liquid, and a negative pressure environment is arranged in the separating device.

S2: in the circulating process, the vapor separated by the separation device is compressed and heated by the vapor compression device to obtain compressed vapor, and the compressed vapor is introduced into the heating device to be used as a 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 the predetermined factor, the radioactive waste liquid is led out of the heating device and the separating device.

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

In some embodiments, the gas in the separation device may be pumped by means of a vacuum pump to create a negative pressure environment in the separation device before beginning to treat the radioactive waste liquid.

In some embodiments, the pressure in the separation device may also be monitored during the circulation process, and if the pressure in the separation device is higher than the desired negative pressure, the vacuum pump is turned on to draw gas from the separation device to maintain the negative pressure environment in the separation device.

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

In some embodiments, the outlet of the separation device is provided with a first pumping hole, the heating device is provided with a second pumping hole, and the gas in the separation device can be pumped from one of the first pumping hole and the second pumping hole when the negative pressure environment is established; the non-condensable gas in the heating device can be extracted from the second extraction opening when extracted.

In some embodiments, the temperature of the feed liquid in the separation device may be monitored, and if the temperature of the feed liquid in the separation device is lower than the evaporation temperature, the vacuum pump is started to pump out the non-condensable gas in the heating device.

In some embodiments, during the process of establishing the negative pressure environment in the separation device by means of the vacuum pump and extracting the non-condensable gas in the heating device, the gas extracted by the vacuum pump is subjected to a cooling process by means of the cooling device, so that the steam in the gas extracted by the vacuum pump is recovered as the condensed liquid.

In some embodiments, the condensate recovered by the cooling device may be introduced into the radioactive waste.

Some specific technical details of the radioactive waste liquid treatment method can be referred to the description of the relevant parts of the radioactive waste liquid treatment system, and are not repeated herein.

The present invention has been described in detail with reference to the drawings and examples, but the present invention is not limited to the examples, and various changes can be made within the knowledge of those skilled in the art without departing from the spirit of the present invention. The prior art can be adopted in the content which is not described in detail in the invention.

Claims

1. A radioactive waste liquid treatment method comprises the following steps:

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 the radioactive waste liquid so as to evaporate the radioactive waste liquid in the separation device, the separation device is used for separating steam generated when the radioactive waste liquid is evaporated so as to concentrate the radioactive waste liquid, and a negative pressure environment is arranged in the separation device;

during the circulation, compressing and heating the steam separated by the separation device by means of a steam compression device to obtain compressed steam, introducing the compressed steam into the heating device as a first heat source of the heating device, and enabling the radioactive waste liquid to be continuously concentrated;

after determining that the radioactive waste has been concentrated by a predetermined factor, directing the radioactive waste to the heating device and the separation device.

2. The method of claim 1, further comprising:

establishing a negative pressure environment in the separation device by means of a vacuum pump in communication with the separation device.

3. The method of claim 2, wherein constructing a negative pressure environment comprises:

before the radioactive waste liquid is treated, gas in the separation device is pumped by a vacuum pump to establish a negative pressure environment in the separation device.

4. The method of claim 3, wherein constructing a negative pressure environment further comprises:

and monitoring the pressure in the separation device during the circulation process, and if the pressure in the separation device is higher than the expected negative pressure, starting the vacuum pump to pump gas in the separation device so as to maintain the negative pressure environment in the separation device.

5. The method of claim 4, further comprising:

and pumping out the non-condensable gas in the heating device by means of the vacuum pump.

6. The method according to 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 establishing of the negative pressure environment in the separation device by means of the vacuum pump comprises:

extracting gas in the separation device from one of the first pumping port and the second pumping port;

the extracting the non-condensable gasses in the heating device comprises:

and extracting the non-condensable gas in the heating device from the second air extraction port.

7. The method of claim 5 or 6, further comprising:

and monitoring the temperature of the material liquid in the separation device, and if the temperature of the material 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:

in the process of establishing a negative pressure environment in the separation device by means of the vacuum pump and extracting the non-condensable gas in the heating device, cooling the gas extracted by the vacuum pump by means of a cooling device so as to recover steam in the gas extracted by the vacuum pump as condensed liquid.

9. The method of claim 8, further comprising:

introducing the condensate recovered by the cooling device into the radioactive spent liquor.

10. A radioactive liquid waste treatment system comprising:

a heating device, wherein a liquid flow channel for flowing the radioactive waste liquid and a gas flow channel arranged outside the liquid flow channel are formed on the heating device, and the gas flowing in the gas flow channel can exchange heat with the radioactive waste liquid in the liquid flow channel so as to heat the radioactive waste liquid;

a separation device for separating steam from the radioactive waste liquid after the heat treatment to concentrate the radioactive waste liquid;

a circulation line communicating the separation device with an inlet of the liquid flow channel;

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

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

a vacuum pump in communication with the separation device, the vacuum pump for drawing gas from the separation device to create a negative pressure environment in the separation device;

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

and the discharge port is arranged in the circulating pipeline and used for leading out the concentrated radioactive waste liquid.

11. The system of claim 10, wherein the vacuum pump is further configured to extract non-condensable gasses in the heating device.

12. The system of claim 11, wherein a first pumping port is provided at an outlet of the separation device, a second pumping port is provided in the gas flow passage of the heating device, and the vacuum pump is in communication with the separation device via the first pumping port and the second pumping port.

13. The system of claim 11, 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 extracted by the vacuum pump so as to recover steam in the gas extracted by the vacuum pump into condensate.

14. The system of claim 11, further comprising:

and the filtering device is communicated with an outlet of the vacuum pump and is used for filtering radioactive substances in the gas extracted by the vacuum pump.

15. The system of claim 14, further comprising:

and the exhaust pipe is detachably arranged at the outlet of the filtering device and is used for exhausting the gas in the filtering device.

16. The system of claim 15, wherein the exhaust pipe is provided in a segmented configuration.