Monitoring System for Nuclear Criticality Safety of Sedimentation Reactor

Abstract

An embodiment of the present invention discloses a monitoring system for nuclear critical safety of a precipitation reactor. The precipitation reactor is used to convert a plutonium nitrate solution into a plutonium precipitate, and the plutonium precipitate adheres to the inner wall of the precipitation reactor to form a sediment. The monitoring system includes: a measuring device, which is arranged outside the precipitation reactor, and is used to detect the gamma rays generated by the decay of the sediment and output a pulse signal; a control device, which is connected to the measuring device and is used to: obtain the pulse signal and determine the counting rate of the gamma rays according to the pulse signal, and judge the state of nuclear critical safety of the precipitation reactor according to the counting rate, so as to judge whether the precipitation reactor is operating normally and safely, thereby ensuring the nuclear critical safety and industrial safety of the precipitation reactor under long-term use.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of nuclear criticality safety, and in particular to a monitoring system for nuclear criticality safety of a precipitation reactor. Background Art

[0002] In the plutonium tail treatment of spent fuel reprocessing, most of the time, precipitation and calcination methods are used to convert plutonium nitrate solution into solid plutonium dioxide. There are many conversion methods used, for example, using hydrogen peroxide, hydrofluoric acid or oxalic acid to precipitate plutonium. At present, precipitation reactors are usually used for the precipitation process of plutonium. However, after repeated use, the inner wall of the precipitation reactor is prone to accumulation of plutonium precipitates and formation of scars, resulting in an increase in the mass of plutonium in each batch of precipitation liquid, increasing the risk of nuclear criticality safety. In addition, as the sediment gradually accumulates, it may fall to the bottom of the precipitator and block the pipeline, affecting the normal operation of the precipitation reactor. Summary of the invention

[0003] According to one aspect of the present invention, a monitoring system for nuclear criticality safety of a precipitation reactor is provided. The precipitation reactor is used to convert a plutonium nitrate solution into a plutonium precipitate, and the plutonium precipitate adheres to the inner wall of the precipitation reactor to form a sediment. The monitoring system includes: a measuring device, which is arranged outside the precipitation reactor, and is used to detect the gamma rays generated by the decay of the sediment and output a pulse signal; a control device, which is connected to the measuring device and is used to: obtain the pulse signal and determine the count rate of the gamma rays according to the pulse signal, and judge the state of nuclear criticality safety of the precipitation reactor according to the count rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Other objects and advantages of the present invention will become apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings, which will help to provide a comprehensive understanding of the present invention.

[0005] Figure 1 It is a schematic diagram of an application scenario of a monitoring system according to an embodiment of the present invention.

[0006] Figure 2 yes Figure 1 Cross-sectional view of the precipitation reactor and monitoring system.

[0007] Figure 3 is a schematic structural diagram of a measuring device according to an embodiment of the present invention.

[0008] Figure 4 1 is a schematic structural diagram of a lifting device according to an embodiment of the present invention.

[0009] Figure 5 yes Figure 4 A schematic structural diagram of the lifting device from another perspective.

[0010] Figure 6 Schematic diagram of the structure of a monitoring system according to an embodiment of the present invention.

[0011] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding.

[0012] Description of reference numerals:

[0013] 100. measuring device; 110. gamma ray detector; 120. shielding collimator; 121. incident channel; 130. connecting cable;

[0014] 200, control device; 210, control module; 220, data acquisition module; 230, data analysis module; 240, storage module; 250, alarm module; 260, display module; 270, input module; 280, emergency power supply module;

[0015] 300, lifting device; 310, support rod; 320, first support part; 321, fixing part; 330, axial moving part; 331, driving part; 332, transmission part; 340, second support part; 350, fixing part;

[0016] 10. Sedimentation reactor; 11. Sediment; 12. Insulation layer. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in conjunction with the drawings of the embodiments of the present application. Obviously, the described embodiment is one embodiment of the present application, not all embodiments. Based on the described embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0018] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in this application should be the usual meanings understood by people with general skills in the field to which this application belongs. If the full text involves descriptions such as "first" and "second", the descriptions such as "first" and "second" are only used to distinguish similar objects, and cannot be understood as indicating or implying their relative importance, order of precedence, or implicitly indicating the number of technical features indicated. It should be understood that the data described by "first" and "second" can be interchangeable under appropriate circumstances. If "and / or" appears in the full text, its meaning is to include three parallel schemes, taking "A and / or B" as an example, including scheme A, or scheme B, or schemes that A and B meet at the same time. In addition, for the convenience of description, spatial relative terms such as "above", "below", "top", "bottom", etc. can be used here, which are only used to describe the spatial position relationship between a device or feature as shown in the figure and other devices or features, and should be understood to also include different orientations in use or operation except for the orientation shown in the figure.

[0019] One embodiment of the present invention provides a precipitation reactor nuclear criticality safety monitoring system. The precipitation reactor 10 is used to convert plutonium nitrate solution into plutonium precipitate. Figure 2 As shown, the plutonium precipitate is easily attached to and deposited on the inner wall of the precipitation reactor 10 to form a sediment 11. In addition, the precipitation reactor 10 is also provided with a thermal insulation layer 12. The thermal insulation layer 12, for example, thermal insulation glass fiber, is wrapped around the outside of the inner wall surface of the precipitation reactor to ensure the temperature conditions required for the precipitation process.

[0020] In some examples, oxalic acid is used to convert the plutonium nitrate solution into a plutonium oxalate precipitate. The sediment 11 in this embodiment can be a plutonium oxalate precipitate. The plutonium oxalate precipitate has fixed components, good crystallization, and is easy to filter and wash. In addition, the plutonium oxalate solubility is low, and a higher plutonium recovery rate can be obtained. In addition, the production process of plutonium oxalate is stable, easy to control, and can achieve continuous operation.

[0021] The monitoring system of the present invention can be used to monitor the nuclear criticality safety of the precipitation reactor during the production of plutonium oxalate precipitation, thereby ensuring the nuclear criticality safety and industrial safety of the precipitation reactor under long-term use.

[0022] like Figure 1 As shown, the monitoring system in one embodiment of the present invention includes a measuring device 100 and a control device 200. The measuring device 100 is arranged outside the precipitation reactor 10, so that the monitoring system will not affect the process of plutonium precipitation during use. In some embodiments, the measuring device 100 is arranged close to the outer wall of the precipitation reactor 10. The measuring device 100 is used to detect the gamma rays generated by the decay of the sediment 11 and output a pulse signal.

[0023] The control device 200 is connected to the measuring device 100 and is used to obtain the pulse signal of the measuring device 100 and determine the gamma ray counting rate according to the pulse signal. The control device 200 can also determine the nuclear criticality safety state of the precipitation reactor 10 according to the counting rate.

[0024] In some examples, the measuring device 100 is connected to the control device 200 by wire. For example, the measuring device 100 is connected to the control device 200 via a connecting cable 130 , thereby achieving communication between the measuring device 100 and the control device 200 .

[0025] The embodiment of the present invention determines the state of the precipitation reactor 10 by the counting rate, and can determine whether the precipitation reactor 10 is operating normally and safely, thereby ensuring the nuclear criticality safety and industrial safety of the precipitation reactor under long-term use.

[0026] Figure 3 FIG. 2 shows a schematic diagram of the structure of a measuring device according to an embodiment of the present invention. Figure 2 and Figure 3 As shown, the measuring device 100 includes a gamma-ray detector 110 and a shielding collimator 120. The gamma-ray detector 110 is used to detect the gamma-rays generated by the decay of the sediment, and the shielding collimator 120 is wrapped around the outer surface of the gamma-ray detector 110, and is used to shield the interference of gamma-rays in the environment and collimate the gamma-rays from the sediment 11. The shielding collimator 120 is provided with an incident channel 121 on the side facing the precipitation reactor 10, and the incident channel 121 is used to provide a channel for the gamma-rays generated by the sediment 11 to be incident on the gamma-ray detector 110, so that the gamma-ray detector 110 can only detect the gamma-rays generated by the decay of plutonium in the sediment 11 at the height position directly facing it, and prevent the gamma-rays from other directions from being incident on the gamma-ray detector 110.

[0027] In one example, the shielding collimator 120 is a lead shielding layer, which can effectively shield interference from gamma rays in other directions. The other directions are directions other than the direction in which the gamma ray detector 110 faces the precipitation reactor 10 .

[0028] Optionally, the shielding collimator 120 is a cylinder, and the gamma-ray detector 110 is disposed at the center of the cylinder of the shielding collimator 120. The cylinder is provided with an incident channel 121 in the direction facing the sediment 11, so that the gamma-ray detector 110 can detect the gamma rays generated by the sediment 11 at the height position facing it, and prevent gamma rays from other directions from being incident on the gamma-ray detector 110 to cause interference, thereby playing a collimating role.

[0029] When the measuring device 100 in this embodiment is located at a certain height position outside the precipitation reactor 10, it can only detect the gamma rays at this height position, and then obtain the composition, thickness and mass of the sediment at this height position.

[0030] In order to detect the distribution of the sediment 11 in the entire precipitation reactor, the monitoring system in this embodiment may further include a lifting device 300. The measuring device 100 is installed on the lifting device 300, and the lifting device 300 is used to drive the measuring device 100 to move in the axial direction of the precipitation reactor 10 to detect the gamma rays and their count rates at different height positions of the precipitation reactor 10, thereby realizing scanning measurement in the axial direction of the entire precipitation reactor.

[0031] It should be noted that the precipitation reactor 10 in this embodiment is an axisymmetric reactor, and the distribution of the sediment 11 in the circumferential direction of the inner wall at each height of the precipitation reactor 10 is roughly the same. That is, at a certain height, the sediment 11 is evenly distributed on the inner wall along the circumferential direction of the precipitation reactor 10. However, along the axial direction of the precipitation reactor 10, the distribution of the sediment 11 is quite different. In one example, there are more sediments 11 in the bottom area of ​​the inner wall of the precipitation reactor 10.

[0032] In this embodiment, the lifting device 300 is used to drive the measuring device 100 to move up and down in the axial direction of the precipitation reactor 10, so as to determine the distribution of the sediment 11 in the axial direction of the precipitation reactor 10. According to the distribution in the axial direction, the distribution of the sediment 11 on the inner wall of the entire precipitation reactor 10 can be determined.

[0033] like Figure 4 and Figure 5As shown, the lifting device 300 includes a support rod 310, a first support portion 320 and an axial moving portion 330. A fixing portion 350 is provided at the lower end of the support rod 310, and the fixing portion 350 can fix the support rod 310 on the ground. The first support portion 320 is slidably arranged along the support rod 310, and the measuring device 100 is fixed on the first support portion 320. The axial moving portion 330 is connected to the first support portion 320, and is used to drive the first support portion 320 to move in the axial direction along the support rod 310. The first support portion 320 can drive the measuring device 100 to move in the axial direction by moving up and down.

[0034] Specifically, the axial moving part 330 includes a driving member 331 and a transmission member 332. The lifting device 300 further includes a second supporting part 340, which is fixed on the supporting rod 310 and spaced apart from the first supporting part 320. The transmission member 332 is rotatably connected between the first supporting part 320 and the second supporting part 340, and the first supporting part 320 has a transmission matching part that matches the transmission member 332. The driving member 331 is installed on the second supporting part 340, and the output shaft of the driving member 331 is connected to the transmission member 332, and the driving member 331 is used to drive the transmission member 332 to rotate. The transmission member 332 rotates and realizes the movement of the first supporting part 320 along the supporting rod 310 through the cooperation between the transmission member 332 and the transmission matching part.

[0035] In this embodiment, the driving member 331 is a driving motor, and the transmission member 332 is a lead screw, which can conveniently and stably control the measuring device 100 to move up and down in the axial direction of the precipitation reactor 10.

[0036] In one example, a fixing member 321 is provided on the first support portion 320, and the fixing member 321 is used to fix the measuring device 100. For example, the fixing member 321 has a groove, and the measuring device 100 can be positioned in the groove to prevent the displacement of the measuring device 100, and also prevent the measuring device 100 from rotating to cause the incident channel 121 to be displaced to a direction not facing the precipitation reactor 10.

[0037] Optionally, the lifting device 300 may include a support rod, a first support portion, a second support portion and an axially movable portion. The first support portion and the second support portion are fixed to the support rod at intervals, the transmission member of the axially movable portion is rotatably connected between the first support portion and the second support portion, and the driving member is installed on the first support portion or the second support portion to drive the transmission member to rotate. The lifting device also includes a fixing member for fixing and installing the measuring device. The fixing member is slidably arranged on the transmission member, and a transmission matching portion that matches the transmission member is arranged on the fixing member. The fixing member can be moved up and down by rotating the transmission member, thereby driving the measuring device 100 to move up and down.

[0038] like Figure 6 As shown, the control device 200 of the monitoring system in this embodiment includes a control module 210, and the control module 210 is connected to the axial moving part 330, and is used to control the measuring device 100 to move to a specified height position in the axial direction of the precipitation reactor 10 at a fixed time, so as to achieve the scanning measurement of the measuring device 100 in the axial direction at a fixed time. For example, the control module 210 is used to control the driving member 331, and then control the measuring device 100 to move from top to bottom in the axial direction of the precipitation reactor 10, and can move a predetermined distance at a predetermined time interval, and the predetermined distance can be equal to the height of the incident channel 121, so as to achieve the scanning measurement of the measuring device 100 in the axial direction of the precipitation reactor 10, and then obtain the thickness of the sediment 11 at each height position of the precipitation reactor 10.

[0039] In this embodiment, the control device 200 includes a data acquisition module 220. The data acquisition module 220 is connected to the measuring device 100, and is used to acquire the pulse signal of the measuring device and analyze and process the pulse signal to convert the pulse signal into a count rate, so that the state of the precipitation reactor 10 can be determined according to the detected count rate.

[0040] The control device 200 further includes a data analysis module 230, which is in communication with the data acquisition module 220. The data acquisition module 220 transmits the count rate to the data analysis module 230, and the data analysis module 230 can receive the count rate sent by the data acquisition module 220, so as to determine the state of the precipitation reactor 10 according to the count rate. In one example, the data analysis module 230 can summarize and calculate the count rates received at different heights, so as to determine the state of nuclear criticality safety of the precipitation reactor.

[0041] In this embodiment, the data analysis module 230 is further used to determine the thickness of the sediment 11 on the inner wall of the precipitation reactor 10 according to the detected count rate and the linear relationship between the count rate and the thickness.

[0042] The linear relationship between the count rate and the thickness of the sediment is obtained in advance based on simulation calculations. Based on the established model of a sedimentation reactor with sediments of different thicknesses, the response and count of the gamma-ray detector under different thicknesses are calculated to obtain the relationship between the count rate and the thickness of the sediment 11. The relationship between the count rate and the thickness of the sediment 11 obtained in this embodiment is a linear relationship.

[0043] The control device 200 in this embodiment also includes a storage module 240. The linear relationship between the counting rate and the thickness of the sediment 11 can be pre-stored in the storage module 240, so that the data analysis module 230 can determine the thickness of the sediment 11 on the inner wall of the sedimentation reactor 10 based on the detected counting rate and the linear relationship, for example, the thickness of the sediment 11 at each height position in the axial direction of the sedimentation reactor 10.

[0044] In this embodiment, the correspondence between the count rate and the mass and distribution state of the sediment 11 may be determined based on the count rate of the precipitation reactor 10 during the trial operation, the linear relationship, and the composition of the sediment 11 .

[0045] The monitoring system can be used to monitor the gamma ray count rate during the trial operation of the precipitation reactor 10. During the trial operation of the precipitation reactor 10, the gamma ray count rate is detected by the measuring device 100, and the thickness of the sediment 11 is determined based on the detected count rate and the linear relationship obtained by pre-simulation calculation. After the thickness of the sediment 11 is determined, the mass of the sediment 11 is determined in combination with the composition of the sediment 11. The composition of the sediment 11 includes the ratio between various plutonium isotopes in the sediment 11, such as the ratio between plutonium 239 and plutonium 240. Based on the calculated mass of the sediment 11 and the detected count rate, the corresponding relationship between the count rate and the mass of the sediment 11 can be determined.

[0046] In addition, after determining the thickness and mass of the sediment 11 at each height position in the axial direction of the precipitation reactor 10, the distribution state of the sediment 11 on the inner wall of the precipitation reactor 10 can be determined. The distribution state includes: the distribution state of the sediment 11 in the axial direction of the precipitation reactor 10, for example, the distribution of the thickness and / or mass of the sediment 11 in the axial direction, or the change of the thickness and / or mass with the height of the precipitation reactor 10. According to the distribution state of the sediment 11 obtained by calculation and analysis and the count rate obtained by detection, the corresponding relationship between the count rate and the distribution state of the sediment 11 can be determined.

[0047] Optionally, the correspondence between the counting rate and the mass and distribution state of the sediment 11 can be stored in the storage module 240, so that the monitoring system can analyze the detected counting rate to determine the distribution of the sediment 11 when the sedimentation reactor 10 is officially in operation.

[0048] This embodiment can determine the corresponding relationship between the mass and distribution state of the sediment 11 and the counting rate based on the detection results during the trial operation of the sedimentation reactor 10, so as to provide reference data for monitoring when the sedimentation reactor 10 is officially in operation.

[0049] Before the precipitation reactor is officially put into operation, the precipitation reactor 10 can be scanned and measured by the measuring device 100, and the data analysis module 230 can be used to determine the mass and distribution of the sediment 11 on the inner wall of the precipitation reactor 10, for example, the distribution of the thickness and / or mass of the sediment 11 in the axial direction, based on the detected counting rates at different height positions of the precipitation reactor 10 and the corresponding relationship between the counting rates and the mass and distribution status of the sediments.

[0050] It should be noted that the various height positions in the embodiment of the present invention represent the various regions corresponding to the different heights of the precipitation reactor 10. In one example, the precipitation reactor 10 can be divided into multiple layers from the bottom to the top, and the height of each layer is a predetermined height value, and the various height positions represent the regions corresponding to the layers of the precipitation reactor 10. For example, if the predetermined height value is 10 cm, then one of the height positions is the region corresponding to the height of 0 to 10 cm of the precipitation reactor 10.

[0051] In this embodiment, the data acquisition module 220 is also used to acquire the pulse signal of the measuring device 100 and process the pulse signal to convert it into a gamma spectrum. The data analysis module 230 can also receive the gamma spectrum sent by the data acquisition module 220 and determine the current composition of the sediment 11 according to the characteristic peaks of the gamma spectrum.

[0052] Among them, the characteristic peaks of gamma rays generated by the decay of different plutonium isotopes are different. Therefore, according to the characteristic peaks of the gamma energy spectrum, the ratio of various plutonium isotopes in the sediment 11 can be analyzed and determined, for example, the ratio between plutonium 239 and plutonium 240, so as to determine the composition of the sediment 11.

[0053] During the trial operation of the precipitation reactor 10, the monitoring system of this embodiment can detect the energy spectrum of gamma rays generated by the decay of the sediment 11, and determine the composition of the sediment 11 based on the gamma energy analysis, thereby obtaining the corresponding relationship between the composition of the sediment 11 and the gamma energy spectrum.

[0054] Optionally, the correspondence between the components of the sediment and the gamma energy spectrum may be stored in the storage module 240 , so that the monitoring system can analyze the detected energy spectrum when the precipitation reactor 10 is officially in operation.

[0055] This embodiment can determine the correspondence between the components of the sediment 11 and the gamma spectrum according to the detection results during the trial operation of the precipitation reactor 10, so as to provide reference data for monitoring when the precipitation reactor 10 is officially in operation.

[0056] Before the precipitation reactor is officially put into operation, the precipitation reactor 10 can be scanned and measured by the measuring device 100, and the data analysis module 230 can be used to determine the composition of the sediment 11 on the inner wall of the precipitation reactor 10 based on the detected gamma energy spectrum and the correspondence between the gamma energy spectrum and the sediment composition.

[0057] In some embodiments, the data analysis module is used to indicate whether the precipitation reactor 10 needs to be cleaned based on the composition, quality and distribution of the sediment 11 on the inner wall of the precipitation reactor 10 .

[0058] Specifically, the data analysis module 230 can determine the content of multiple plutonium isotopes in the precipitation reactor 10 based on the composition, quality and distribution of the sediment 11. When the content of the plutonium isotope is equal to or exceeds the set safety threshold, it indicates that the precipitation reactor 10 needs to be cleaned, thereby giving clear usage recommendations and promptly reminding technicians to clean the inside of the precipitation reactor before use.

[0059] For example, during the trial operation of the precipitation reactor 10, the technician can set a safety threshold based on the trial operation results (including the count rate and the sediment composition, thickness, quality and distribution). The safety threshold represents the range of safe operation of the precipitation reactor 10. When the safety threshold is exceeded, it means that the precipitation reactor 10 may be or will be dangerous and needs to be cleaned.

[0060] The control device 200 may include an input module 270 , and a technician may input the set safety threshold into the control device 200 through the input module 270 .

[0061] This embodiment can give nuclear criticality safety advice before the precipitation reactor 10 is put into operation, and based on the detection results and analysis and judgment, give an indication signal of whether the precipitation reactor 10 needs to be cleaned, so that the precipitation reactor 10 can be cleaned in time to eliminate the risk before a possible criticality accident occurs.

[0062] In one example, the data analysis module 230 is further used to determine the state of the precipitation reactor 10 according to the characteristic peak of the gamma spectrum. When the characteristic peak of the gamma spectrum changes, it is determined that the precipitation reactor 10 is in an abnormal state.

[0063] Specifically, the composition of the plutonium nitrate solution is fixed, and after the plutonium nitrate solution is converted into plutonium precipitate, the composition of the plutonium precipitate is also fixed, so the characteristic peak of the gamma spectrum generated by the sediment 11 is also fixed. If the characteristic peak of the gamma spectrum monitored by the monitoring system changes during the operation of the precipitation reactor 10, it can be determined that the composition of the sediment 11 has changed, and then it can be determined that the precipitation reactor 10 has an abnormality. For example, when the process of the plutonium precipitation process is abnormal, the concentration of plutonium isotopes in the plutonium nitrate solution changes, which causes the composition of the plutonium precipitate to change.

[0064] In this embodiment, it is possible to judge whether the composition of the sediment 11 has changed based on the change of the characteristic peak of the gamma energy spectrum, and further determine whether the precipitation reactor 10 is abnormal.

[0065] In this embodiment, the control device 200 further includes an alarm module 250. The alarm module 250 is used to give an alarm prompt when the precipitation reactor 10 is in an abnormal state. Specifically, when the data analysis module 230 determines that the precipitation reactor 10 is in an abnormal state, it instructs the alarm module 250 to give an alarm prompt. After receiving the alarm instruction of the data analysis module 230, the alarm module 250 can give an alarm prompt, for example, in the form of sound, light, signal, etc., so as to remind the technicians to eliminate the abnormal state as soon as possible to avoid further expansion of the accident and cause corresponding risks.

[0066] In addition, the data analysis module 230 can also analyze and determine the current nuclear criticality safety parameters of the precipitation reactor 10 according to the mass and distribution of the sediment 11 on the inner wall of the precipitation reactor 10. Optionally, the data analysis module 230 can calculate the current nuclear criticality safety parameters of the precipitation reactor 10 based on the mass and distribution of the sediment 11 detected based on a pre-established precipitation reactor model. The nuclear criticality safety parameters include an effective multiplication coefficient.

[0067] In this embodiment, the normal operating range of the precipitation reactor 10 may be determined based on the count rate of the precipitation reactor 10 during the trial operation.

[0068] For example, the monitoring system can be used to monitor the count rate during the trial operation of the precipitation reactor 10. During the trial operation of the precipitation reactor 10, the count rate of gamma rays is detected by the measuring device 100, and the normal operating range of the count rate of the precipitation reactor 10 during normal operation is calculated based on a pre-established model. After determining the normal operating range, the normal operating range can be stored in the storage module 240.

[0069] During the formal operation of the precipitation reactor 10, the measuring device 100 monitors the gamma ray counting rate of the precipitation reactor 10 in real time, and the data analysis module 230 is used to determine whether the counting rate monitored by the measuring device 100 in real time is within the normal operating range.

[0070] Among them, when the count rate is within the normal operating range, it indicates that the current state of the precipitation reactor 10 is a normal operating state. When the count rate exceeds the normal operating range, it indicates that the current state of the precipitation reactor 10 is an abnormal state, and the alarm module 250 is instructed to give an alarm prompt, so that the phenomena of excessive material operation and abnormal material addition in the precipitation reactor 10 can be monitored and warned, and the occurrence of critical accidents can be discovered and prevented, and the staff can be reminded to eliminate the accidents as soon as possible in the early stage of the incident to avoid further expansion of the accidents and corresponding risks.

[0071] In addition, the control device 200 in this embodiment further includes a display module 260, which is used to display the detected count rate, gamma spectrum, and parameters such as composition, thickness, mass, and distribution of the sediment 11. Optionally, the display module 260 displays the corresponding parameters in the form of data or charts.

[0072] In one example, when the data analysis module 230 indicates that the precipitation reactor 10 needs to be cleaned, the display module 260 may further display the cleaning suggestion to instruct the technician to clean the inside of the precipitation reactor.

[0073] In one example, when the alarm module 250 uses a signal alarm mode to alarm, the display module 260 is also used to display an alarm prompt. Optionally, the alarm prompt can be highlighted on the display module 260, so as to promptly remind the technician that the precipitation reactor is in an abnormal state.

[0074] The control device 200 further includes an emergency power supply 280. When the monitoring system loses external power supply, the emergency power supply 280 is used to supply power to the entire monitoring system, thereby ensuring that the monitoring task can be completed normally.

[0075] In addition, the control device 200 also includes modules such as a high-voltage power supply and an amplifier. The high-voltage power supply is used to provide high voltage to the gamma-ray detector, and the amplifier is used to filter and amplify the pulse signal of the gamma-ray detector and transmit it to the data acquisition module.

[0076] The monitoring system in the embodiment of the present invention can monitor the nuclear criticality safety of the precipitation reactor, and can clarify whether the inside of the precipitation reactor needs to be cleaned before use, thereby improving the equipment productivity while ensuring nuclear criticality safety and giving clear guidance and suggestions. During use, an alarm can be issued for abnormal conditions, reducing nuclear criticality safety risks and ensuring the safety of personnel and equipment.

[0077] Regarding the embodiments of the present invention, it should also be noted that, in the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to obtain new embodiments.

[0078] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A monitoring system for nuclear criticality safety of a precipitation reactor, characterized in that: The precipitation reactor is used to convert the plutonium nitrate solution into plutonium precipitate, and the plutonium precipitate adheres to the inner wall of the precipitation reactor to form a sediment; The monitoring system comprises: A measuring device, disposed outside the precipitation reactor, for detecting gamma rays generated by the decay of the sediment and outputting a pulse signal; A control device connected to the measuring device, for: acquiring the pulse signal and determining the count rate of the gamma ray according to the pulse signal, and judging the state of nuclear criticality safety of the precipitation reactor according to the count rate; A lifting device, on which the measuring device is installed, and the lifting device is used to drive the measuring device to move in the axial direction of the precipitation reactor to detect the gamma ray counting rates at different height positions of the precipitation reactor; The control device comprises: A data acquisition module, connected to the measuring device, for acquiring the pulse signal of the measuring device and converting it into a counting rate; A storage module, in which a linear relationship between the counting rate and the thickness of the sediment is pre-stored; A data analysis module is in communication with the data acquisition module, and is used to: receive the detected count rate, and determine the thickness of the sediment on the inner wall of the precipitation reactor according to the count rate and the linear relationship between the count rate and the thickness.

2. The monitoring system according to claim 1, characterized in that: The measuring device comprises: a gamma-ray detector for detecting gamma rays generated by the decay of the sediment; A shielding collimator is wrapped around the outer surface of the gamma-ray detector and is used to shield gamma rays in the environment; wherein, an incident channel is provided on the side of the shielding collimator facing the precipitation reactor, and the incident channel is used to provide a channel for the gamma rays generated by the sediment to be incident on the gamma-ray detector.

3. The monitoring system according to claim 1, characterized in that: The lifting device comprises: Support rod, A first supporting portion, wherein the first supporting portion is slidably disposed along the supporting rod, and the measuring device is fixed on the first supporting portion; An axial moving portion, wherein the axial moving portion is connected to the first supporting portion and is used to drive the first supporting portion to move in an axial direction along the supporting rod.

4. The monitoring system according to claim 3, characterized in that: The lifting device further includes: a second support portion, the second support portion being fixed on the support rod; The axial moving part comprises: A transmission member, rotatably connected between the first support portion and the second support portion, wherein the first support portion has a transmission matching portion matching with the transmission member; A driving member is installed on the second supporting part, and the driving member is connected to the transmission member for driving the transmission member to rotate so as to drive the first supporting part to move along the supporting rod.

5. The monitoring system according to claim 3 or 4, characterized in that: The control device comprises: The control module is connected to the axial moving part and is used to control the measuring device to move to a specified height position in the axial direction of the precipitation reactor at a fixed time.

6. The monitoring system according to claim 1, characterized in that: The data analysis module is also used for: The mass and distribution of the sediment on the inner wall of the sediment reactor are determined according to the counting rates at different height positions of the sediment reactor and the corresponding relationship between the counting rates and the mass and distribution state of the sediment.

7. The monitoring system according to claim 6, characterized in that: The correspondence between the count rate and the mass and distribution state of the sediment is determined based on the count rate of the precipitation reactor during a test run, the linear relationship, and the composition of the sediment.

8. The monitoring system according to claim 7, characterized in that: The data analysis module is used for: According to the composition, quality and distribution of the sediment on the inner wall of the precipitation reactor, it is indicated whether the precipitation reactor needs to be cleaned.

9. The monitoring system according to claim 1, characterized in that: The data acquisition module is also used to acquire the pulse signal of the measuring device and convert it into a gamma energy spectrum; The control device further comprises a data analysis module, which is in communication with the data acquisition module and is used for receiving the gamma energy spectrum and determining the current composition of the sediment according to the characteristic peaks of the gamma energy spectrum.

10. The monitoring system according to claim 9, characterized in that: The data analysis module is also used for: Judging the state of the precipitation reactor according to the characteristic peaks of the gamma spectrum; When the characteristic peak of the gamma spectrum changes, it is determined that the precipitation reactor is in an abnormal state.

11. The monitoring system according to claim 10, characterized in that: The control device comprises: an alarm module, and the alarm module is used to give an alarm prompt when the precipitation reactor is in an abnormal state.

12. The monitoring system according to claim 11, characterized in that: The data analysis module is used for: Determining whether the count rate monitored in real time by the measuring device is within a normal operating range; When the counting rate exceeds the normal operating range, the alarm module is instructed to issue an alarm prompt.

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