Spent fuel sample total alpha and total beta activity analysis system and transportation and analysis method

Abstract

The invention belongs to the technical field of elemental analysis, and provides a spent fuel sample total alpha and total beta activity analysis system and a spent fuel sample total alpha and total beta activity transportation and analysis method.The system comprises a glove box and an analysis unit, and a shielding chamber and a conveying assembly are installed in the glove box; a detector assembly is mounted in the shielding chamber and is used for detecting a sample in the shielding chamber; the conveying assembly is used for conveying samples, and the samples are placed in the tray; the analysis unit is located outside the glove box, connected with the detector and used for analyzing data detected by the detector. According to the analysis system, split design of the glove box and the analysis unit is adopted, the part in contact with the sample is placed in the glove box, the radioactive process sample can be analyzed and detected, the risk of radioactive substance leakage is reduced, meanwhile, the analysis unit is placed outside the glove box, radiation of the radioactive substance is avoided, the service life is prolonged, and the cost is reduced. And the maintenance operation is also convenient.

Description

Technical Field

[0001] The invention belongs to the technical field of element analysis, and particularly relates to a system, transportation and analysis method for total alpha and total beta activity analysis of spent fuel samples. Background Art

[0002] Spent fuel contains a variety of chemical substances such as uranium, plutonium, neptunium, and splinter elements, which are highly radioactive. Spent fuel reprocessing is to use the different distribution ratios of key nuclides such as uranium and plutonium in the water nitric acid system-30% tributyl phosphate / kerosene system to separate uranium and plutonium elements from splinter elements, and at the same time separate uranium and plutonium from each other, so as to achieve the purpose of extracting useful elements such as uranium and plutonium. Therefore, in the reprocessing process, process samples such as spent fuel storage pool water, process and three waste discharge wastewater, medium and low-level waste liquid, and evaporated condensate are all radioactive, and the total α and total β radioactivity concentrations in them need to be measured to ensure the safe and stable operation of the process and the safety of personnel. The measurement of total α and total β in reprocessing process samples is not only an inevitable requirement for process operation control, waste liquid reception, storage and discharge, and glass solidification and cement solidification waste liquid treatment, but also an important part of environmental radiation monitoring.

[0003] The existing α and β analyzers are mainly used to measure environmental water bodies (lake water, sea water, groundwater, etc.), soil and atmosphere. However, the composition of reprocessing process samples is complex, containing multiple radionuclides, which interfere seriously with each other. When using existing α and β analyzers for measurement, the results have large deviations and there is α and β crosstalk. In addition, medium and high radioactive samples cannot be measured directly in an open environment. Therefore, the existing α and β analyzers cannot meet the needs of measuring total α and total β activity in spent fuel reprocessing process samples. Summary of the invention

[0004] In order to solve the problems in the background technology, the present invention proposes a spent fuel sample total α and total β activity analysis system, transportation and analysis method.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A system for analyzing total alpha and total beta activities of spent fuel samples, comprising a glove box and an analysis unit, wherein a shielding room and a conveying assembly are installed in the glove box;

[0007] A detector assembly is installed inside the shielding room, and the detector assembly is used to detect samples in the shielding room;

[0008] The conveying assembly is used to convey samples, and the samples are placed in a tray;

[0009] The conveying assembly includes a first sample rack, a second sample rack and a conveyor belt; the conveyor belt passes through the shielding room; the first sample rack is located on one side of the shielding room and at one end of the conveyor belt; the second sample rack is located on the other side of the shielding room and at the other end of the conveyor belt;

[0010] The analysis unit is located outside the glove box and connected to the detector assembly, and is used for analyzing data detected by the detector assembly.

[0011] Preferably, the detector assembly comprises:

[0012] Main detector;

[0013] an anti-coincidence detector, the anti-coincidence detector wrapping the main detector;

[0014] The anti-coincidence detector is provided with an inorganic scintillation crystal detector and a photomultiplier tube, and the inorganic scintillation crystal detector is coupled with the photomultiplier tube.

[0015] Preferably, in the conveying assembly:

[0016] The conveyor belt is equipped with a conveyor motor, and the conveyor motor is used to drive the conveyor belt to move;

[0017] The first sample rack is cylindrical, with an opening at the bottom, and a limiting device is installed at the opening;

[0018] The first sample rack is located above the conveyor belt, and the distance L1 between the opening and the conveyor belt satisfies: 2H>L1>H, where H represents the height of a single tray;

[0019] The second sample rack is cylindrical, with an opening at the bottom, and a lifting device installed at the opening;

[0020] The second sample rack is located above the conveyor belt, and a distance L2 between the opening and the conveyor belt satisfies: 2H>L2>H.

[0021] Preferably, the limiting device comprises:

[0022] A symmetrical limiting plate is slidably arranged along the radial direction of the first sample rack and is perpendicular to the conveying path of the conveyor belt, and is located between the opening of the first sample rack and the conveyor belt;

[0023] A symmetrical first cylinder connected to the limit plate;

[0024] The end of the limit plate away from the first cylinder is arc-shaped and provided with a step surface, and the end of the step surface is provided with a chamfer;

[0025] When limiting, the step surface abuts against the bottom of the tray of the sample.

[0026] Preferably, the lifting device comprises:

[0027] Spring sheets, one end of a plurality of the spring sheets being uniformly fixed on the inner wall of the opening of the second sample holder along the circumferential direction, and the upper surface of the spring sheets being fixedly connected to the inner wall bracket of the second sample holder by a spring;

[0028] A lifting rod, located directly below the second sample holder;

[0029] The second cylinder is connected to the lifting rod and is used to drive the lifting rod to perform lifting movement.

[0030] Preferably, the analysis unit comprises:

[0031] an amplifier, electrically connected to the detector assembly, and used to amplify a signal output by the detector assembly;

[0032] an analog-to-digital converter, electrically connected to the amplifier, and configured to convert the analog signal output by the amplifier into a digital signal;

[0033] A pulse analyzer, electrically connected to the analog-to-digital converter, for performing pulse analysis on the digital signal to obtain a separated pulse signal;

[0034] A processing module, electrically connected to the pulse analyzer, for performing pulse spectrum formation, nuclide identification and activity calculation on the pulse signal;

[0035] The main control circuit is electrically connected to the amplifier, the analog-to-digital converter, the pulse analyzer and the processing module respectively.

[0036] A transport method, applied to the above-mentioned spent fuel sample total alpha and total beta activity analysis system, comprises the following steps:

[0037] releasing the sample to be tested onto a conveyor belt through a first sample holder;

[0038] The samples to be tested are transported to the shielded room via a conveyor belt and then tested on site;

[0039] transporting the tested samples to directly below the second sample rack;

[0040] The tested samples are recovered to the second sample rack through the lifting device.

[0041] Preferably, releasing the sample to be tested to the conveyor belt through the first sample holder comprises the following steps:

[0042] placing a stack of samples to be tested in a first sample holder;

[0043] The first cylinder periodically drives the limit plate away from the opening of the first sample rack, so that the sample to be tested falls onto the conveyor belt;

[0044] When the sample to be tested falls onto the conveyor belt, the limit plate is reset to abut against the next sample to be tested.

[0045] Preferably, the detected sample is recovered to the second sample rack by a lifting device, comprising the following steps:

[0046] The second cylinder drives the lifting rod to lift the tray of the tested sample;

[0047] The tray squeezes the spring sheet so that the spring sheet swings upward from bottom to top until the sample after testing moves to the top of the spring sheet;

[0048] After the tested sample moves to the top of the spring piece, the lifting rod is reset, and the spring piece is reset by the gravity of the tested sample.

[0049] An analysis method, applied to the above-mentioned spent fuel sample total alpha and total beta activity analysis system, comprises the following steps:

[0050] Detecting the combined alpha and beta pulses and the gamma pulse of the sample through a main detector in the detector assembly, and detecting the gamma pulse through an anti-coincidence detector in the detector assembly;

[0051] The α, β, γ pulses detected by the main detector and the γ pulse detected by the anti-coincidence detector are calculated by the anti-coincidence algorithm to obtain the α and β combined pulses of the sample;

[0052] The α and β combined pulses of the sample are separated by pulse discrimination algorithm and pulse shape analysis to obtain the α pulse and β pulse of the sample;

[0053] An α spectrum and a β spectrum are obtained based on the α pulse and the β pulse.

[0054] Beneficial effects of the present invention:

[0055] 1. The analysis system of the present invention adopts a split design of a glove box and an analysis unit. The part in contact with the sample is placed in the glove box, which can analyze and detect radioactive process samples and reduce the risk of leakage of radioactive substances. At the same time, the analysis unit is placed outside the glove box to avoid radiation from radioactive substances, extend the service life, and facilitate inspection and maintenance operations;

[0056] 2. The conveying method of the present invention realizes the process of automatic release and automatic recovery of samples during the detection process through the limit device and the lifting device. The whole process reduces manual operation, increases the automation process, avoids direct contact between human body and radioactive substances, and the operation is safer;

[0057] 3. The analysis method of the present invention uses different detectors to shield the γ pulse according to the characteristics of α, β and γ pulses, and finally separates the combined pulses of α and β, so as to accurately measure the activities of total α and total β in the post-processing process samples.

[0058] Other features and advantages of the present invention will be described in the following description, and partly become obvious from the description, or be understood by implementing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0060] Figure 1 A schematic diagram of a spent fuel sample total α and total β activity analysis system of the present invention is shown;

[0061] Figure 2 The schematic diagram of the structure of the conveying assembly and the shielding room is shown;

[0062] Figure 3a A schematic diagram of a first sample rack and a limiting device is shown;

[0063] Figure 3b A three-dimensional schematic diagram of the limiting device is shown;

[0064] Figure 4 A schematic diagram of a second sample rack and a lifting device is shown;

[0065] Figure 5 A schematic diagram of a mechanical transmission mechanism is shown;

[0066] Figure 6 A flow chart showing the delivery method of the present invention is shown;

[0067] Figure 7 A flow chart of the analysis method of the present invention is shown;

[0068] Figure 8 An algorithm flow chart of the analysis method of the present invention is shown.

[0069] In the figure: 1. first sample rack; 2. second sample rack; 3. main detector; 4. anti-coincidence detector; 401. inorganic scintillation crystal detector; 402. photomultiplier tube; 5. shielding room; 6. amplifier; 7. analog-to-digital converter; 8. pulse analyzer; 9. processing module; 10. main control circuit; 11. conveying motor; 12. limit device; 1201. limit plate; 1202. first cylinder; 13. conveyor belt; 14. lifting device; 1401. shrapnel; 1402. spring; 1403. lifting rod; 1404. second cylinder; 15. glove box; 16. lifting motor; 17. screw; 18. driven wheel; 19. transmission belt. DETAILED DESCRIPTION

[0070] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0071] A system for analyzing the total alpha and beta activities of spent fuel samples, such as Figure 1 As shown, it includes a glove box 15 and an analysis unit, wherein a shielding room 5 and a conveying assembly are installed in the glove box 15. A detector assembly is installed inside the shielding room 5, and the detector assembly can detect samples in the shielding room 5. Specifically, the shielding room 5 is used to shield the influence of radioactive particles and cosmic rays in the surrounding environment. It is made of lead, and lead can play a good radioactive shielding effect. The detector assembly is located in the middle of the shielding room 5 as a whole, and the shielding body surrounds the detector assembly to play a shielding role. The conveying assembly can convey samples, and the samples are placed in a tray and move along the conveying path. The conveying assembly includes a first sample rack 1, a second sample rack 2 and a conveyor belt 13, wherein the conveyor belt 13 passes through the shielding room 5, the first sample rack 1 is located on one side of the shielding room 5, and is located at one end of the conveyor belt 13, and the second sample rack 2 is located on the other side of the shielding room 5, and is located at the other end of the conveyor belt 13; the analysis unit is located outside the shielding room 5 and is connected to the detector assembly for analyzing the data detected by the detector assembly.

[0072] It should be noted that the analysis system of the present invention adopts a split design of the glove box 15 and the analysis unit. The part in contact with the sample is placed in the glove box 15, which can analyze and detect the radioactive process sample and reduce the risk of leakage of radioactive substances. At the same time, the analysis unit is placed outside the glove box 15 to avoid radiation from radioactive substances, extend the service life, and facilitate inspection and maintenance operations.

[0073] Combine the following Figure 2-Figure 5The analysis system is further described.

[0074] like Figure 2 As shown, the detector assembly is located above the conveyor belt 13, and includes a main detector 3 and an anti-coincidence detector 4, wherein the anti-coincidence detector 4 wraps the main detector 3, and the anti-coincidence detector 4 is provided with an inorganic scintillation crystal detector 401 and a photomultiplier tube 402, and the inorganic scintillation crystal detector 401 is coupled with the photomultiplier tube 402.

[0075] It should be noted that the main detector 3 is a Passivated Ion-Implanted Planar Silicon Detector (PIPS) detector. Compared with scintillation detectors and gas flow proportional counters, PIPS detectors have small size, high resolution, and good α ion resolution. The anti-coincidence detector 4 is a Thallium doped Cesium Iodide (CsI(TI)) detector. Compared with plastic scintillators and other inorganic scintillators, CsI(TI) scintillator has the characteristics of high density, high light energy yield, and high detection efficiency for γ rays, and is a good anti-coincidence detector 4. The PIPS main detector 3 responds to α, β and γ pulses, and the anti-coincidence detector 4 only responds to γ ​​in structure, so the interference of γ pulses can be deducted by anti-coincidence to reduce costs.

[0076] Furthermore, in the conveying assembly, the conveying belt 13 is provided with a conveying motor 11, and the conveying motor 11 is used to drive the conveying belt 13 to move. In addition, the first sample rack 1 is cylindrical, with an opening at the bottom, and a limiting device 12 is installed at the opening; the first sample rack 1 is located above the conveying belt 13, and the distance L1 between the opening and the conveying belt 13 satisfies: 2H>L1>H, where H represents the height of a single tray. The second sample rack 2 is also cylindrical, with an opening at the bottom, and a lifting device 14 is installed at the opening. The second sample rack 2 is located above the conveying belt 13, and the distance L2 between the opening and the conveying belt 13 satisfies: 2H>L2>H.

[0077] It should be noted that when the tray loaded with samples moves with the conveyor belt 13, in order to ensure that the first sample rack 1 and the second sample rack 2 do not interfere with the tray, it is necessary to limit the distance between the outlet of the sample rack and the conveyor belt 13. In the first sample rack 1, the tray is stacked with the sample. When the first sample rack 1 releases the tray and the sample, a certain gap is maintained between the top of the tray and the outlet of the first sample rack 1. Similarly, the second sample rack 2 is set in the same way.

[0078] like Figure 3a As shown, the limiting device 12 can abut the tray from the bottom of the first sample rack 1 (a is the sample, b is the tray). Figure 3b It can be seen that the limiting device 12 includes a limiting plate 1201 and a first cylinder 1202. There are two limiting plates 1201, which are symmetrically arranged with the first sample rack 1 as the center. Moreover, the limiting plate 1201 is arranged to slide radially along the first sample rack 1, and the sliding direction is perpendicular to the conveying path of the conveyor belt 13. At the same time, the limiting plate 1201 is located between the opening of the first sample rack 1 and the conveyor belt 13. Moreover, the two limiting plates 1201 are also respectively connected to the first cylinder 1202, and the two first cylinders 1202 can also be symmetrically installed on both sides of the first sample rack 1. In addition, the end of the limiting plate 1201 away from the first cylinder 1202 is arc-shaped and is provided with a step surface. The end of the step surface is provided with a chamfer. When limiting, the step surface is against the bottom of the sample tray.

[0079] It should be noted that during operation, the limit plate 1201 can move to both sides, at which time the tray will fall into the conveyor belt 13, and then the limit plate 1201 will be reset under the drive of the first cylinder 1202, thereby resisting other trays and samples above.

[0080] like Figure 4 As shown, the lifting device 14 includes a spring 1401, a spring 1402 and a lifting rod 1403. Specifically, one end of two symmetrical springs 1401 is evenly fixed on the inner wall of the opening of the second sample rack 2 along the circumferential direction, and the upper surface of the spring 1401 is fixedly connected to the inner wall bracket of the second sample rack 2 to the spring 1402. The lifting rod 1403 is located directly below the second sample rack 2; the second cylinder 1404 is connected to the lifting rod 1403, and is used to drive the lifting rod 1403 to move up and down.

[0081] It should be noted that, when the tray and the sample move to the opening position of the second sample rack 2, the second cylinder 1404 can drive the lifting rod 1403 to rise, so that the tray enters the second sample rack 2, and then the tray squeezes the spring piece 1401 until it moves above the spring piece 1401, and then the lifting rod 1403 is reset, and the tray presses down the spring piece 1401 under the action of gravity, and then the spring piece 1401 can press against the tray from the bottom, thereby completing the recovery.

[0082] It should be further explained that, in order to avoid interference, the lifting rod 1403 can be bent inward from the outside of the conveyor belt 13 for installation.

[0083] like Figure 5As shown, in some optional embodiments, the second cylinder 1404 can be replaced by a mechanical transmission mechanism, which includes a lifting motor 16, a screw 17, a driven wheel 18 and a transmission belt 19, wherein the lifting motor 16 drives the driven wheel 18 to rotate through the transmission belt 19 of the output shaft, and the driven wheel 18 is fixedly connected to the screw 17, so the screw 17 rotates synchronously with the driven wheel 18, and finally the screw 17 drives the lifting rod 1403 (at this time, the lifting rod 1403 needs to be matched with the bottom of the screw 17 thread, and a limit block for limiting the rotation of the lifting rod 1403) to move in the vertical direction.

[0084] Furthermore, combined with Figure 1 The analysis unit includes an amplifier 6, an analog-to-digital converter 7, a pulse analyzer 8, a processing module 9 and a main control circuit 10. The amplifier 6 is electrically connected to the detector assembly; the analog-to-digital converter 7 is electrically connected to the amplifier 6; the pulse analyzer 8 is electrically connected to the analog-to-digital converter 7; the processing module 9 is electrically connected to the pulse analyzer 8; and the main control circuit 10 is electrically connected to the amplifier 6, the analog-to-digital converter 7, the pulse analyzer 8 and the processing module 9 respectively.

[0085] It should be noted that the amplifier 6 is used to amplify the signal output by the detector assembly, improve the signal-to-noise ratio of the signal, and reduce interference during the transmission process. The analog-to-digital converter 7 is used to convert the analog signal output by the amplifier 6 into a digital signal for further processing. The pulse analyzer 8 (Field Programmable Gate Array, FPGA) integrates an anti-coincidence algorithm and a pulse discrimination algorithm, and performs pulse analysis processing such as anti-coincidence subtraction and pulse discrimination on the signal to separate the α pulse and the β pulse. The processing module 9 is provided with a dedicated analysis software for α and β pulse spectrum formation, nuclide identification and activity calculation, etc., so as to realize the activity measurement of total α and total β in the post-processing process sample. It has the functions of system parameter setting, instrument automatic control, data acquisition, analysis, storage and display, instrument calibration, etc.

[0086] For example, the following is based on Figure 1-Figure 5 A conveying method is given by the system, and its process is as follows Figure 6 As shown, the following steps are included:

[0087] S1: releasing the sample to be tested to the conveyor belt 13 through the first sample rack 1, specifically including:

[0088] S101: stack the samples to be tested and place them in the first sample rack 1; S102: periodically drive the limit plate 1201 away from the opening of the first sample rack 1 through the first cylinder 1202, so that the samples to be tested fall onto the conveyor belt 13; S103: after the samples to be tested fall onto the conveyor belt 13, the limit plate 1201 is reset to resist the next sample to be tested.

[0089] S2: The sample to be tested is transported to the shielding room 5 via the conveyor belt 13 and then tested.

[0090] S3: transport the tested samples to the bottom of the second sample rack 2.

[0091] S4: Recovering the tested sample to the second sample rack 2 by the lifting device 14, specifically including:

[0092] S401: The lifting rod 1403 is driven by the second cylinder 1404 to lift the tray of the tested sample; S402: The spring piece 1401 is squeezed by the tray to make the spring piece 1401 swing from bottom to top until the tested sample moves above the spring piece 1401; S403: After the tested sample moves above the spring piece 1401, the lifting rod 1403 is reset, and the spring piece 1401 is reset by the gravity of the tested sample.

[0093] It should be noted that the above S1-S4 realizes the process of automatic release and automatic recovery of samples during the detection process through the limit device 12 and the lifting device 14. The whole process reduces manual operations, increases automated processes, avoids direct human contact with radioactive substances, and makes the operation safer.

[0094] An analysis method is applied to the above-mentioned spent fuel sample total alpha and total beta activity analysis system, combined with Figure 7 and Figure 8 It can be seen that the following steps are included:

[0095] D1: Detecting the α and β of the sample and the γ pulses from the environment and the sample through the main detector 3 in the detector assembly, and detecting the γ pulses in the environment and the sample through the anti-coincidence detector 4 in the detector assembly;

[0096] D2: Calculate the α, β, γ pulses detected by the main detector 3 and the γ pulse detected by the anti-coincidence detector 4 through the anti-coincidence algorithm to obtain the α and β combined pulses of the sample;

[0097] D3: Separate the α and β combined pulses of the sample through pulse discrimination algorithm and pulse shape analysis to obtain the α pulse and β pulse of the sample;

[0098] D4: Obtain α spectrum and β spectrum based on α pulse and β pulse.

[0099] It should be noted that the analysis method of the present invention uses different detectors to shield the γ pulse according to the characteristics of α, β and γ pulses, and finally separates the combined pulses of α and β, so as to accurately measure the activity of total α and total β in the post-processing process sample.

[0100] An analyzer, integrating the above system, works as follows:

[0101] 1) Turn on the power of the instrument, turn on the temperature control system, and preheat the instrument for 5 minutes.

[0102] 2) Place the samples to be measured in the first sample rack 1 in order and record the sample number and sample information. A maximum of 60 samples can be arranged for the same measurement task.

[0103] 3) Open the instrument measurement software and set relevant parameters: information entry, calibration program (background calibration parameters, α source efficiency calibration parameters, β source efficiency calibration parameters, etc.), measurement program (sample number, counting time, number of repetitions, etc.).

[0104] 4) Click on "Measure", and the conveying component will automatically transfer the sample to be measured to the measurement position according to the set program. During measurement, the main detector 3 detects α, β and γ rays, and the CsI (TI) detector detects γ rays. The signal of the main detector 3 is amplified by the amplifier 6 to amplify the current signal, and the signal is converted by the analog-to-digital converter 7. The γ signal detected by the anti-coincidence detector 4 is also converted by the analog-to-digital converter 7. The signal of the main detector 3 is anti-coincided with the γ pulse signal detected by the anti-coincidence detector 4 through the anti-coincidence algorithm in the multi-channel pulse analyzer 8, and the output signal is only α and β pulses, and then the α and β pulses are discriminated by the pulse discrimination algorithm, and finally the output is independent α pulses and β pulses. After the measurement is completed, the instrument automatically controls the sample conveying component to move the sample out of the measurement position and transfer it to the second sample rack 2 for storage.

[0105] 5) The processing module 9 counts the separated α pulses and β pulses, forms spectra, obtains α and β energy spectra, and simultaneously performs nuclide identification and activity calculation, and the calculation results are displayed on the software operation interface.

[0106] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A system for analyzing total α and total β activity of spent fuel samples, characterized in that: It comprises a glove box (15) and an analysis unit, wherein a shielding room (5) and a conveying assembly are installed in the glove box (15); A detector assembly is installed inside the shielding room (5), and the detector assembly is used to detect samples in the shielding room (5); The conveying assembly is used to convey samples, and the samples are placed in a tray; The conveying assembly comprises a first sample rack (1), a second sample rack (2) and a conveyor belt (13); the conveyor belt (13) passes through the shielding room (5); the first sample rack (1) is located on one side of the shielding room (5) and at one end of the conveyor belt (13); the second sample rack (2) is located on the other side of the shielding room (5) and at the other end of the conveyor belt (13); The analysis unit is located outside the glove box (15) and is connected to the detector assembly, and is used for analyzing data detected by the detector assembly.

2. A spent fuel sample total α and total β activity analysis system according to claim 1, characterized in that: The detector assembly comprises: Main detector (3); an anti-coincidence detector (4), wherein the anti-coincidence detector (4) wraps around the main detector (3); The anti-coincidence detector (4) is provided with an inorganic scintillation crystal detector (401) and a photomultiplier tube (402), and the inorganic scintillation crystal detector (401) is coupled to the photomultiplier tube (402).

3. A spent fuel sample total α and total β activity analysis system according to claim 1, characterized in that: In the conveying assembly: The conveyor belt (13) is equipped with a conveyor motor (11), and the conveyor motor (11) is used to drive the conveyor belt (13) to move; The first sample rack (1) is cylindrical, with an opening at the bottom, and a limiting device (12) is installed at the opening; The first sample rack (1) is located above the conveyor belt (13), and the distance L1 between the opening and the conveyor belt (13) satisfies: 2H>L1>H, where H represents the height of a single tray; The second sample rack (2) is cylindrical, with an opening at the bottom, and a lifting device (14) is installed at the opening; The second sample rack (2) is located above the conveyor belt (13), and a distance L2 between the opening and the conveyor belt (13) satisfies: 2H>L2>H.

4. A spent fuel sample total α and total β activity analysis system according to claim 3, characterized in that: The limiting device (12) comprises: A symmetrical limiting plate (1201) is slidably arranged along the radial direction of the first sample rack (1), is perpendicular to the conveying path of the conveyor belt (13), and is located between the opening of the first sample rack (1) and the conveyor belt (13); A symmetrical first cylinder (1202) connected to the limiting plate (1201); The end of the limiting plate (1201) away from the first cylinder (1202) is arc-shaped and provided with a step surface, and the end of the step surface is provided with a chamfer; When limiting, the step surface abuts against the bottom of the tray of the sample.

5. A spent fuel sample total α and total β activity analysis system according to claim 4, characterized in that: The lifting device (14) comprises: Spring sheets (1401), one end of a plurality of the spring sheets (1401) being evenly fixed on the inner wall of the opening of the second sample holder (2) along the circumferential direction, and a spring (1402) being fixedly connected between the upper surface of the spring sheet (1401) and the inner wall bracket of the second sample holder (2); A lifting rod (1403), located directly below the second sample rack (2); The second cylinder (1404) is connected to the lifting rod (1403) and is used to drive the lifting rod (1403) to perform lifting movement.

6. A spent fuel sample total α and total β activity analysis system according to claim 1, characterized in that: The analysis unit comprises: An amplifier (6), electrically connected to the detector assembly, and used to amplify the signal output by the detector assembly; an analog-to-digital converter (7), electrically connected to the amplifier (6), and used for converting the analog signal output by the amplifier (6) into a digital signal; A pulse analyzer (8), electrically connected to the analog-to-digital converter (7), for performing pulse analysis on the digital signal to obtain a separated pulse signal; A processing module (9), electrically connected to the pulse analyzer (8), for performing pulse spectrum formation, nuclide identification and activity calculation on the pulse signal; The main control circuit (10) is electrically connected to the amplifier (6), the analog-to-digital converter (7), the pulse analyzer (8) and the processing module (9) respectively.

7. A conveying method, characterized in that: A spent fuel sample total alpha and total beta activity analysis system applied to claim 4 or 5, comprising the following steps: Releasing the sample to be tested to a conveyor belt (13) through a first sample rack (1); The sample to be tested is transported to the shielding room (5) via a conveyor belt (13) and then tested on site; transporting the tested sample to directly below the second sample rack (2); The tested samples are recovered to the second sample rack (2) through the lifting device (14).

8. A conveying method according to claim 7, characterized in that: The method comprises the following steps: releasing the sample to be tested to a conveyor belt (13) through a first sample rack (1); Stacking samples to be tested and placing them in a first sample rack (1); The first cylinder (1202) periodically drives the limiting plate (1201) away from the opening of the first sample rack (1), so that the sample to be tested falls onto the conveyor belt (13); When the sample to be tested falls onto the conveyor belt (13), the limiting plate (1201) is reset to abut against the next sample to be tested.

9. A conveying method according to claim 8, characterized in that: The sample after detection is recovered to the second sample rack (2) by a lifting device (14), comprising the following steps: The lifting rod (1403) is driven by the second cylinder (1404) to lift the tray of the sample after the test; The tray squeezes the spring sheet (1401) to make the spring sheet (1401) swing upward from bottom to top until the sample after testing moves to the top of the spring sheet (1401); After the tested sample moves to the top of the spring sheet (1401), the lifting rod (1403) is reset, and the spring sheet (1401) is reset by the gravity of the tested sample.

10. An analysis method, characterized in that A spent fuel sample total alpha and total beta activity analysis system applied to any one of claims 1 to 6, comprising the following steps: Detecting the combined α and β pulses and the γ pulse of the sample through a main detector (3) in the detector assembly, and detecting the γ pulse through an anti-coincidence detector (4) in the detector assembly; The α, β, and γ pulses detected by the main detector (3) and the γ pulse detected by the anti-coincidence detector (4) are calculated by an anti-coincidence algorithm to obtain α and β combined pulses of the sample; The α and β combined pulses of the sample are separated by pulse discrimination algorithm and pulse shape analysis to obtain the α pulse and β pulse of the sample; An α spectrum and a β spectrum are obtained based on the α pulse and the β pulse.

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