Radiation measurement and radioactive decontamination device and method for refueling pool of reactor of nuclear power station

Abstract

The invention provides a nuclear power plant reactor refueling pool radiation measurement and radioactive decontamination device which is installed on a refueling crane and comprises a guide rail arranged on the refueling crane, and a radiation measurement module, a radioactive decontamination module and a compressed air purging module which are installed on the guide rail in a sliding mode. The invention further provides a radiation measurement and radioactive decontamination method for the refueling pool of the reactor of the nuclear power station. The device is compact in structure, has scalability, and can be flexibly installed according to actual working conditions on site. Meanwhile, the refueling crane is used as a carrier, the device moves back and forth through the moving track of the refueling crane, and full-coverage radiation level measurement and radioactive decontamination on the refueling pool are ensured in the mode that the telescopic driving arm and the device guide rail are used for moving up and down and left and right.

Description

Technical Field

[0001] The invention relates to the technical field of radiation monitoring and radioactive decontamination, and in particular to a device and method for radiation measurement and radioactive decontamination of a reactor refueling pool in a nuclear power plant. Background Art

[0002] The reactor refueling pool of a nuclear power plant is located in the reactor containment, and is divided into two parts: the reactor internals compartment and the pressure vessel compartment. During the shutdown and refueling maintenance of the nuclear power plant, due to the extremely strong radioactivity of the spent fuel, it is necessary to carry out unloading, equipment inspection, pressure testing, loading and other operations in the refueling pool. The water layer can provide shielding for the workers in the containment. When the refueling pool is drained, the corrosion activation products will adhere to the bottom and inner wall of the pool. In order to control the radiation dose of the maintenance personnel and prevent the spread of contamination, the refueling pool must be decontaminated after each unloading and loading, so that the maintenance personnel can work in a clean and safe working environment, ensuring the radiation safety of personnel and the environment. The decontamination of the refueling pool mainly includes the radiation measurement and radioactivity removal of the refueling pool, which is completed by professionals entering the refueling pool.

[0003] In the current decontamination work of the reactor refueling pool in nuclear power plants, radiation measurement and radioactive decontamination are carried out manually, which has problems such as low decontamination efficiency, long decontamination time, and high radiation in the refueling pool environment, which leads to high radiation doses for operators.

[0004] The Chinese patent with publication number CN202887752U introduces a nuclear power plant refueling machine radiation monitoring device, including a refueling crane and a radiation monitoring device, which is used to monitor the radiation level above the refueling pool during the loading and unloading of nuclear fuel. The Chinese patent with publication number CN212160098U introduces a nuclear power plant radiation level remote monitoring device, including an instrument placement grid, a universal telescopic column, a telescopic column sleeve, a telescopic leg sleeve, a telescopic leg, and a foot. The present invention is mainly aimed at the environmental survey and high-pressure water washing and decontamination of the water pool after the loading and unloading is completed, and integrates the real-time radiation environmental survey of the on-site water pool, high-pressure water washing and decontamination, and pressure-controlled purge. Summary of the invention

[0005] The purpose of the present invention is to provide a radiation measurement and radioactive decontamination device and method for a nuclear power plant reactor refueling pool, which solves the problems of low decontamination efficiency and long decontamination time in manual methods and high radiation dose to operators caused by high environmental radiation in the refueling pool.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A radiation measurement and radioactive decontamination device for a nuclear power plant reactor refueling pool is installed on a refueling carriage and comprises a guide rail arranged on the refueling carriage, and a radiation measurement module, a radioactive decontamination module and a compressed air purge module slidably installed on the guide rail.

[0008] As an implementable manner, the radiation measurement module includes a radiation measurement probe, a telescopic drive arm, and a sliding sleeve. The sliding sleeve is slidably mounted on the guide rail, one end of the telescopic drive arm is mounted on the sliding sleeve, and the radiation measurement probe is mounted on the other end.

[0009] As an practicable manner, the radioactive decontamination module includes a decontamination nozzle, a high-pressure water pump, a telescopic drive arm, a sliding sleeve and a water pipe. The sliding sleeve is slidably installed on the guide rail, one end of the telescopic drive arm is installed on the sliding sleeve, and the decontamination nozzle is installed on the other end. The decontamination nozzle is connected to the high-pressure water pump through the water pipe.

[0010] As an implementable manner, a water pipe positioning ring is provided on the telescopic driving arm to fix the water pipe.

[0011] As an practicable manner, the decontamination nozzle is a Y-shaped nozzle.

[0012] As an practicable manner, the compressed air purge module includes a purge nozzle, an air compressor, a telescopic drive arm, a sliding sleeve and an air pipe. The sliding sleeve is slidably installed on the guide rail, one end of the telescopic drive arm is installed on the sliding sleeve, and the purge nozzle is installed on the other end. The purge nozzle is connected to the air compressor through the air pipe.

[0013] As an implementable manner, a trachea positioning ring is provided on the telescopic driving arm to fix the trachea.

[0014] As an practicable manner, the purge nozzle is a Y-shaped nozzle.

[0015] The nuclear power plant reactor refueling pool radiation measurement and radioactive decontamination device also includes a control console module, which controls the radiation measurement module, the radioactive decontamination module, and the compressed air purge module, and is connected in parallel to the telescopic drive arm. The control console module completes height control, measurement, decontamination, and pressure-controlled purge operations.

[0016] A method for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant, comprising the following steps:

[0017] S1: Confirm that the refueling pool has been drained and start the radiation measurement and radioactive decontamination device of the nuclear power plant reactor refueling pool;

[0018] S2: The radiation measurement module receives the instruction of the control console module, measures the radiation level of the bottom and wall of the reactor refueling pool, and obtains the radiation level data information of the refueling pool area;

[0019] S3: The radiation measurement module transmits the acquired radiation level data information of the refueling pool area to the control console module, and the control console module analyzes and processes the acquired radiation level data information according to the program set limit value to determine the area that needs to be decontaminated by radioactivity;

[0020] S4: the console module transmits the data information instruction of the area that needs to be decontaminated by radioactivity to the radioactive decontamination module;

[0021] S5: The radioactive decontamination module receives the instruction and performs high-pressure water jet decontamination on the area of ​​the refueling pool that needs to be decontaminated with radioactive substances;

[0022] S6: After the radioactive decontamination module completes the radioactive decontamination, the signal is fed back to the control console module, and the control console module sends a compressed air purge instruction to the compressed air purge module;

[0023] S7: The compressed air purge module receives the instruction and performs compressed air purge on the refueling pool area;

[0024] S8: After the compressed air purge module completes its work, it feeds back a signal to the control console module, and the control console module sends a radiation measurement instruction to the radiation measurement module;

[0025] S9: The radiation measurement module receives the instruction, measures the radiation level of the refueling water pool, and obtains radiation level data information;

[0026] S10: The radiation measurement module transmits the acquired radiation level data information of the refueling pool area to the control console module, and the control console module determines whether the radiation level of the refueling pool meets the standard after decontamination;

[0027] S11: If the radiation level is up to standard, the decontamination work of the refueling pool is completed, the radiation measurement and radioactive decontamination of the nuclear power plant reactor refueling pool are turned off, and the mechanical structures of the radiation measurement module, the radioactive decontamination module, and the compressed air purge module are restored to standby state; if the radiation level is not up to standard, repeat steps S3-S11 until the radiation level of the refueling pool is up to standard.

[0028] Compared with the prior art, the device and method for measuring radiation and decontaminating radioactive substances in a nuclear power plant reactor refueling pool provided by the present invention has the following beneficial effects:

[0029] The device of the present invention has a compact structure and is scalable, and can be flexibly installed according to the actual working conditions on site. At the same time, the refueling crane is used as a carrier, and its moving track is used to complete the forward and backward movement of the device, and the retractable driving arm and the device guide rail are used to complete the up, down, left and right movement to ensure full coverage of the refueling pool. The radiation level measurement and radioactive decontamination are carried out.

[0030] The present invention can effectively solve the radiation risks and industrial risks brought about by personnel entering the refueling pool to measure radiation levels and carry out radioactive decontamination, improve the efficiency of decontamination of the reactor refueling pool of the nuclear power plant, reduce the radiation dose received by personnel when decontaminating the refueling pool, and provide a new idea for shortening the overhaul period of subsequent nuclear power plants, reducing the radiation dose received by personnel, and improving the radiation protection management level of nuclear power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only 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.

[0032] Figure 1 This is a schematic diagram of the longitudinal structure of a refueling pool for a pressurized water reactor nuclear power plant;

[0033] Figure 2 This is a schematic diagram of the overhead structure of the refueling pool of a pressurized water reactor nuclear power plant;

[0034] Figure 3 A schematic diagram of a module of a radiation measurement and radioactive decontamination device for a nuclear power plant reactor refueling pool provided by an embodiment of the present invention;

[0035] Figure 4 A schematic diagram of a forward assembly of a radiation measurement module provided by an embodiment of the present invention;

[0036] Figure 5 A schematic diagram of a forward assembly of a radioactive decontamination module provided in an embodiment of the present invention;

[0037] Figure 6 A schematic diagram of the forward assembly of a compressed air purge module provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The following is further explained in detail through specific implementation methods.

[0039] In order to facilitate understanding, we first briefly introduce the nuclear power plant refueling pool. Figure 1 and Figure 2As shown, the nuclear power plant includes a refueling pool 20 above the reactor 10 and a refueling carriage 30 located above the refueling pool. The refueling carriage 30 is for operators to stand on to perform refueling related operations. In some embodiments, the reactor 10 is, for example, a pressurized water reactor. In some embodiments, the refueling pool 20 is roughly rectangular, and includes a reactor pool 21 located directly above the reactor 10 and a component pool 22 located on one side of the reactor pool 21 and connected to the reactor pool 21. When the refueling pool 20 is decontaminated, the refueling pool 20 is in an empty and waterless state.

[0040] like Figures 3 to 6 As shown, the present invention provides a radiation measurement and radioactive decontamination device 31 for a nuclear power plant reactor refueling pool, which is installed on both sides of a refueling carriage 30, and includes a radiation measurement module 311, a radioactive decontamination module 312, and a compressed air purge module 313 installed in parallel on a telescopic drive arm, and the control console module 314 completes operations such as height control, measurement, decontamination, and pressure-controlled purge.

[0041] For example, guide rails 3114 are installed at the bottom of the railings on both sides of the refueling crane 30, and telescopic sleeves are slidably installed below the guide rails 3114, and radiation measurement modules 311, radioactive decontamination modules 312, and compressed air purge modules 313 are installed in parallel on the telescopic sleeves. The console module 314 integrates radiation measurement data display, radioactive decontamination control switch, and pressure-controlled purge control switch.

[0042] like Figure 4 As shown, the radiation measurement module 311 includes a radiation measurement probe 3111, a telescopic drive arm 3112 and a sliding sleeve 3113. The guide rail 3114 is installed at the bottom of the railings on both sides of the refueling vehicle 30, close to the refueling pool 20. The sliding sleeve 3113 is installed on the guide rail 3114 and can slide left and right along the guide rail 3114. The telescopic drive arm 3112 is installed on the sliding sleeve 3113 and can be extended up and down. The radiation measurement probe 3111 is installed at the other end of the telescopic drive arm 3112 for measuring the radiation level.

[0043] The radiation measurement module 311 is installed at the bottom of the railings on both sides of the refueling carriage 30, and is used to measure the radiation levels of the pool wall and pool bottom of the refueling pool 20 before decontamination. The radiation measurement module 311 follows the refueling carriage to complete the forward and backward movement, the telescopic drive arm 3112 follows the guide rail 3114 to move left and right, and the radiation measurement probe 3111 follows the telescopic drive arm 3112 to move up and down. In this way, as the refueling carriage 30 moves forward and backward, the radiation measurement module 311 can perform covering radiation measurement on the pool bottom and pool wall of the refueling pool 20.

[0044] like Figure 5As shown, the radioactive decontamination module 312 includes a Y-shaped decontamination nozzle 3121, a high-pressure water pump 3122, a telescopic driving arm 3112, a sliding sleeve 3113, a water pipe positioning ring 3125 and a water pipe 3126. The sliding sleeve 3113 is mounted on the guide rail 3114 and can slide left and right along the guide rail 3114. The telescopic driving arm 3112 is mounted on the sliding sleeve 3113 and can be telescopic up and down. The water pipe positioning ring 3125 is mounted on the upper part of the telescopic driving arm 3112 and is used to fix the water pipe 3126. The Y-shaped nozzle 3121 is mounted on the other end of the telescopic driving arm 3112, and the water pipe 3126 is connected to the quick interface at the upper end of the Y-shaped decontamination nozzle 3121. When the high-pressure water pump 3122 is started, the high-pressure water flow will reach the Y-shaped decontamination nozzle 3121 through the water pipe 3126 to start radioactive flushing and decontamination of the refueling pool 20.

[0045] The radioactive decontamination module 312 is installed at the bottom of the railings on both sides of the refueling carriage 30, and is used for radioactive decontamination of the wall and bottom of the refueling pool 20. The radioactive decontamination module 312 moves forward and backward following the refueling carriage 30, the telescopic drive arm 3112 moves left and right following the guide rail 3114, and the Y-shaped nozzle moves up and down following the telescopic drive arm 3112, ensuring that the radioactive decontamination module 312 can cover the bottom and wall of the refueling pool 20 for flushing and decontamination.

[0046] like Figure 6 As shown, the compressed air purge module 313 includes a Y-shaped purge nozzle 3131, an air compressor 3132, a telescopic drive arm 3112, a sliding sleeve 3113, an air pipe positioning ring 3135 and an air pipe 3136. The sliding sleeve 3113 is mounted on the guide rail 3114 and can slide left and right along the guide rail 3114. The telescopic drive arm 3112 is mounted on the sliding sleeve 3113 and can be telescopic up and down. The air pipe positioning ring 3135 is mounted on the upper part of the telescopic drive arm 3112 and is used to fix the air pipe 3136. The Y-shaped purge nozzle 3131 is mounted on the other end of the telescopic drive arm 3112, and the air pipe 3136 is connected to the quick interface at the upper end of the Y-shaped nozzle 3131. Start the air compressor 3132, and the purge gas reaches the Y-shaped purge nozzle 3131 through the air pipe 3136 to start compressed air purge of the refueling pool 20.

[0047] The compressed air purge module 313 is installed at the bottom of the railings on both sides of the refueling crane 30, and is used for the purge work of the wall and bottom of the refueling pool 20. The compressed air purge module 313 moves forward and backward following the refueling crane 30, the telescopic drive arm 3112 moves left and right following the guide rail 3114, and the Y-shaped purge nozzle 3131 moves up and down following the telescopic drive arm 3112, ensuring that the compressed air purge module 313 can cover the bottom and wall of the refueling pool 20.

[0048] In addition, the present invention provides a method for measuring radiation and decontaminating radioactive materials in a reactor refueling pool of a nuclear power plant based on the device 31 for measuring radiation and decontaminating radioactive materials in a reactor refueling pool of a nuclear power plant, comprising the following steps:

[0049] Step 1: After confirming that the refueling pool 20 has been emptied of water and the preconditions for radioactive decontamination are met, the operator starts the nuclear power plant reactor refueling pool radiation measurement and radioactive decontamination device 31.

[0050] Step 2: The radiation measurement module 311 receives the instruction from the control console module 314, measures the radiation level of the bottom and wall of the reactor refueling pool, and obtains the radiation level data information of the refueling pool 20 area.

[0051] Step 3: The radiation measurement module 311 transmits the acquired radiation level data information of the refueling pool area to the console module 314. The console module 314 analyzes and processes the acquired radiation level data information according to the program set limit value to determine the area that needs to be decontaminated by radioactivity.

[0052] Step 4: The console module 314 transmits the data information instructions of the area that needs to be decontaminated by radioactivity to the radioactive decontamination module 312 .

[0053] Step 5: The radioactive decontamination module 312 receives the instruction and performs high-pressure water jet decontamination on the area of ​​the refueling pool 20 that needs to be decontaminated with radioactive substances.

[0054] Step 6: After completing the radioactive decontamination, the radioactive decontamination module 312 feeds back a signal to the control console module 314 , and the control console module 314 sends a compressed air purge instruction to the compressed air purge module 313 .

[0055] Step 7: The compressed air purge module 313 receives the instruction and performs compressed air purge on the area of ​​the refueling pool 20 .

[0056] Step 8: After the compressed air purge module 313 completes its work, it feeds back a signal to the control console module 314 , and the control console module sends a radiation measurement instruction to the radiation measurement module 311 .

[0057] Step 9: The radiation measurement module 311 receives the instruction, measures the radiation level of the refueling pool 20, and obtains radiation level data information.

[0058] Step 10: The radiation measurement module 311 transmits the acquired radiation level data information of the refueling pool 20 area to the control console module 314, and the control console module 314 determines whether the radiation level of the refueling pool 20 meets the standard after decontamination.

[0059] Step 11: If the radiation level meets the standard, the decontamination work of the refueling pool 20 is completed, the reactor refueling pool radiation measurement and radioactive decontamination automatic device 31 is turned off, and the mechanical structure of each module is restored to the standby state; if the radiation level does not meet the standard, repeat steps 3 to 11 until the radiation level of the refueling pool 20 meets the standard.

[0060] Therefore, the radiation measurement and radioactive decontamination device and method for the reactor refueling pool of a nuclear power plant provided by the present invention effectively solves the radiation risks and industrial risks brought about by personnel entering the refueling pool to measure radiation levels and perform radioactive decontamination, improves the decontamination efficiency of the reactor refueling pool of a nuclear power plant, and reduces the radiation dose received by personnel when performing decontamination of the refueling pool.

[0061] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A radiation measurement and radioactive decontamination device for a nuclear power plant reactor refueling pool, installed on a refueling crane (30), characterized in that: include: A guide rail (3114) is arranged on the refueling carriage (30), and a radiation measurement module (311), a radioactive decontamination module (312), and a compressed air purge module (313) are slidably mounted on the guide rail (3114).

2. The device for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant according to claim 1, characterized in that: The radiation measurement module (311) comprises a radiation measurement probe (3111), a telescopic driving arm (3112), and a sliding sleeve (3113); the sliding sleeve (3113) is slidably mounted on the guide rail (3114); one end of the telescopic driving arm (3112) is mounted on the sliding sleeve (3113), and the other end is mounted on the radiation measurement probe (3111).

3. The device for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant according to claim 1, characterized in that: The radioactive decontamination module (312) comprises a decontamination nozzle, a high-pressure water pump (3122), a telescopic driving arm (3112), a sliding sleeve (3113) and a water pipe (3126); the sliding sleeve (3113) is slidably mounted on the guide rail (3114); one end of the telescopic driving arm (3112) is mounted on the sliding sleeve (3113), and the other end is mounted with the decontamination nozzle; the decontamination nozzle is connected to the high-pressure water pump (3122) via the water pipe (3126).

4. The device for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant according to claim 3, characterized in that: The telescopic driving arm (3112) is provided with a water pipe positioning ring (3125) for fixing the water pipe (3126).

5. The device for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant according to claim 3, characterized in that: The decontamination nozzle is a Y-shaped nozzle (3121).

6. The device for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant according to claim 1, characterized in that: The compressed air purge module (313) includes a purge nozzle, an air compressor (3132), a telescopic drive arm (3112), a sliding sleeve (3113) and an air pipe (3136); the sliding sleeve (3113) is slidably mounted on the guide rail (3114); one end of the telescopic drive arm (3112) is mounted on the sliding sleeve (3113), and the other end is mounted with the purge nozzle; the purge nozzle is connected to the air compressor (3132) via the air pipe (3136).

7. The device for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant according to claim 6, characterized in that: The telescopic driving arm (3112) is provided with an air pipe positioning ring (3135) for fixing the air pipe (3136).

8. The device for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant according to claim 6, characterized in that: The purge nozzle is a Y-shaped nozzle (3121).

9. The device for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant according to claim 1, characterized in that: The system also includes a control console module (314), which controls the radiation measurement module (311), the radioactive decontamination module (312), and the compressed air purge module (313). The control console module (314) is connected in parallel to the telescopic drive arm to complete height control, measurement, decontamination, and pressure-controlled purge operations.

10. A method for measuring radiation and decontaminating radioactive substances in a reactor refueling pool of a nuclear power plant, characterized in that: The following steps are involved: S1: Confirm that the refueling pool has been drained and start the radiation measurement and radioactive decontamination device of the nuclear power plant reactor refueling pool; S2: The radiation measurement module receives the instruction of the control console module, measures the radiation level of the bottom and wall of the reactor refueling pool, and obtains the radiation level data information of the refueling pool area; S3: The radiation measurement module transmits the acquired radiation level data information of the refueling pool area to the control console module, and the control console module analyzes and processes the acquired radiation level data information according to the program set limit value to determine the area that needs to be decontaminated by radioactivity; S4: the console module transmits the data information instruction of the area that needs to be decontaminated by radioactivity to the radioactive decontamination module; S5: The radioactive decontamination module receives the instruction and performs high-pressure water jet decontamination on the area of ​​the refueling pool that needs to be decontaminated with radioactive substances; S6: After the radioactive decontamination module completes the radioactive decontamination, the signal is fed back to the control console module, and the control console module sends a compressed air purge instruction to the compressed air purge module; S7: The compressed air purge module receives the instruction and performs compressed air purge on the refueling pool area; S8: After the compressed air purge module completes its work, it feeds back a signal to the control console module, and the control console module sends a radiation measurement instruction to the radiation measurement module; S9: The radiation measurement module receives the instruction, measures the radiation level of the refueling water pool, and obtains radiation level data information; S10: The radiation measurement module transmits the acquired radiation level data information of the refueling pool area to the control console module, and the control console module determines whether the radiation level of the refueling pool meets the standard after decontamination; S11: If the radiation level is up to standard, the decontamination work of the refueling pool is completed, the radiation measurement and radioactive decontamination of the nuclear power plant reactor refueling pool are turned off, and the mechanical structures of the radiation measurement module, the radioactive decontamination module, and the compressed air purge module are restored to standby state; if the radiation level is not up to standard, repeat steps S3-S11 until the radiation level of the refueling pool is up to standard.

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