Drop disposal method for heavy water reactor spent fuel transport container

Abstract

The present application relates to the technical field of spent fuel dry storage, and discloses a heavy water reactor spent fuel transport container drop disposal method. The method comprises the following operation steps: judging a drop scene of a spent fuel shielding transport container; if the drop occurs in a production plant, establishing a production plant site control area, and placing the spent fuel shielding transport container into a pool without cracks; if the drop occurs on a transport road, using hoisting equipment to hoist the spent fuel shielding transport container back to a transport vehicle, guiding the spent fuel shielding transport container back to the plant under the guidance of a security department guide vehicle, and placing the spent fuel shielding transport container into the pool without cracks; and if the drop occurs in a storage area, establishing a storage area site control area, and transporting the spent fuel shielding transport container back to the plant and placing the spent fuel shielding transport container into a storage pool without cracks. The method is convenient to use, easy to understand, and has high practicability, and can ensure the safety and reliability of spent fuel transfer and has high economic benefits.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of dry storage of spent fuel, and particularly relates to a method for handling a falling of a spent fuel transport container of a heavy water reactor. BACKGROUND

[0002] The two heavy water reactor nuclear power units of the Qinshan nuclear power plant are the only two heavy water reactor units in China. The advantage of the heavy water reactor is that it can be refueled without stopping the reactor. However, due to the limited storage capacity of the refueling pool, a temporary dry storage of spent fuel must be built to ensure the stable operation of the heavy water reactor nuclear power plant. The main method is to transport the spent fuel in the pool for more than 6 years to the storage area by hoisting a special transport container and a special transport vehicle. However, a falling event of the spent fuel shield transport container (FLASK) may occur during hoisting and transportation, thereby causing damage and loss to personnel, equipment, and the environment. SUMMARY

[0003] The present application aims to solve the above-mentioned problems in the prior art and provides a method for handling a falling of a spent fuel transport container of a heavy water reactor, which can reduce the impact on personnel, equipment, and the environment caused by a falling event of the spent fuel shield transport container during hoisting and transportation.

[0004] To solve the above-mentioned problems, the technical solution of the present application is as follows: a method for handling a falling of a spent fuel transport container of a heavy water reactor, which comprises the following operation steps:

[0005] S1: judging the falling scenario of the spent fuel shield transport container; if the falling occurs in the production plant, step S2 is executed, if the falling occurs on the transportation road, step S3 is executed, and if the falling occurs in the storage area, step S4 is executed;

[0006] S2: establishing a production plant site control area, observing and judging whether the spent fuel shield transport container is damaged and has cracks by using the video system in the plant, and putting the spent fuel shield transport container into the pool without cracks;

[0007] S3: using hoisting equipment to hoist the spent fuel shield transport container back to the transport vehicle, returning to the plant under the guidance of the security department, observing and judging whether the spent fuel shield transport container is damaged and has cracks by using the video system in the plant, and putting the spent fuel shield transport container into the pool without cracks;

[0008] S4: establishing a storage area site control area, observing and judging whether the spent fuel shield transport container is damaged and has cracks, and transporting the spent fuel shield transport container back to the plant and putting it into the storage pool without cracks.

[0009] Step S2 further comprises: if the spent fuel shielding transport container has no crack trace, S21 is executed; if the spent fuel shielding transport container has crack trace, S22 is executed.

[0010] S21: placing the spent fuel shielding transport container into the pool;

[0011] S22: after removing the background of the crack trace area of the spent fuel shielding transport container, detecting by the gamma measuring instrument, if the detection value is greater than 100uGy / h and lasts for 15 minutes, it is determined that the spent fuel shielding transport container has cracks, different types of shielding devices are carried by the shielding vehicle and the staff approaches the crack, then the corresponding shielding device is wrapped around the crack through the special dismounting tool, the wrapped part is detected by the gamma measuring instrument, and after confirming that the dose of the wrapped part is obviously reduced and the detection value is less than 100uGy / h, the spent fuel shielding transport container is placed into the pool.

[0012] Step S3 further comprises: if the spent fuel shielding transport container has no crack trace, S31 is executed; if the spent fuel shielding transport container has crack trace, S32 is executed.

[0013] S31: placing the spent fuel shielding transport container into the pool;

[0014] S32: after removing the background of the crack trace area of the spent fuel shielding transport container, detecting by the gamma measuring instrument, if the detection value is greater than 100uGy / h and lasts for 15 minutes, it is determined that the spent fuel shielding transport container has cracks, different types of shielding devices are carried by the shielding vehicle and the staff approaches the crack, then the corresponding shielding device is wrapped around the crack through the special dismounting tool, the wrapped part is detected by the gamma measuring instrument, and after confirming that the dose of the wrapped part is obviously reduced and the detection value is less than 100uGy / h, the spent fuel shielding transport container is placed into the pool.

[0015] Step S4 further comprises: if the spent fuel shielding transport container has no crack trace, S41 is executed; if the spent fuel shielding transport container has crack trace, S42 is executed.

[0016] S41: the spent fuel shielding transport container is hoisted back to the transport vehicle by the hoisting equipment, guided back to the plant by the guard, and placed into the storage pool;

[0017] S42: After the crack trace area of the spent fuel shielding transport container is removed from the background, detection is carried out through a gamma measuring instrument, if the detection value is greater than 100uGy / h, and lasts for 15min, it is determined that the spent fuel shielding transport container has cracks, and different types of shielding devices are carried by the shielding vehicle and approached to the crack together with the staff, then the corresponding shielding device is wrapped around the crack through the special dismounting tool, the wrapping place is detected through the gamma measuring instrument, and after it is confirmed that the dose of the wrapping place is obviously reduced and the detection value is less than 100uGy / h, the spent fuel shielding transport container is hoisted back to the transport vehicle through the hoisting equipment, guided back to the plant under the guidance of the security place, and placed in the storage pool.

[0018] The wrapping is to wrap the spent fuel shielding transport container crack place by lead blanket and lead skin, and tighten with iron wire.

[0019] The significant effect of the present application is that the heavy water reactor spent fuel transport container falling disposal method takes different disposal measures according to the radiation detection state after the spent fuel shielding transport container falls, and effectively reduces the influence on personnel, equipment and environment caused by the spent fuel shielding transport container falling. The method is convenient to use, easy to understand and has strong practicability, ensures the safety and reliability of the spent fuel transfer process, has high economic benefits, has been demonstrated through several exercise tests, and has good use, the method is the first for the heavy water reactor unit spent fuel production, and provides a feasible disposal method for the subsequent similar power plant spent fuel transfer process falling, and can be popularized and applied to similar power stations. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The flow chart of the heavy water reactor spent fuel transport container falling disposal method is described. DETAILED DESCRIPTION

[0021] The technical solutions in the application will be described in detail below with reference to the drawings in the application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of the present application.

[0022] In the description of the present application, it should be noted that the "upper" indicating position or location relationship is based on the position or location relationship shown in the drawings, and is only for the convenience and simplification of description, and does not indicate or imply that the indicated device or element must be provided with a specific position, constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application.

[0023] In the description of the present application, the terms "first", "second" are only for description purpose, and cannot be understood as indicating or implying relative importance.

[0024] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "connect," "dispose," "install," "fix," etc. should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integral connection; they may refer to direct connection, indirect connection through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0025] like Figure 1 As shown, the method for handling a dropped heavy water reactor spent fuel transport container includes the following steps:

[0026] S1: Determine the drop scenario of the spent fuel shielding transport container; if the drop occurs in the production plant, execute step S2; if the drop occurs on the transport road, execute step S3; if the drop occurs in the storage area, execute step S4;

[0027] The falling scenarios of the spent fuel shielding and transport container include: production plant, transportation road, and storage area. Among them, the falling of the spent fuel shielding and transport container in the production plant refers to the falling of the spent fuel shielding and transport container during the transfer from the production plant to the transportation vehicle; the falling of the spent fuel shielding and transport container on the transportation road refers to the falling of the spent fuel shielding and transport container on the transportation road when being transported to the storage area by the transportation vehicle; the falling of the spent fuel shielding and transport container in the storage area refers to the falling of the spent fuel shielding and transport container during the hoisting process in the storage area;

[0028] S2: Establish an on-site control area in the production plant. Use the video system within the plant to observe and determine whether the spent fuel shielding and transport container is damaged or has cracks. If there are no cracks in the spent fuel shielding and transport container, execute S21. If there are cracks in the spent fuel shielding and transport container, execute S22. If there are no cracks in the spent fuel shielding and transport container, place it in the water pool.

[0029] S21: Place the spent fuel shielding transport container into the pool;

[0030] S22: After removing the background of the crack trace area of the spent fuel shielding transport container, detect by the gamma measuring instrument. If the detection value is greater than 100 uGy / h and lasts for 15 min, it is determined that the spent fuel shielding transport container has cracks. Different types of shielding devices are carried by the shielding vehicle and approached to the crack together with the staff. Then, the corresponding shielding device is wrapped around the crack through the special dismounting tool. The wrapped part is detected by the gamma measuring instrument. After confirming that the dose of the wrapped part is obviously reduced and the detection value is less than 100 uGy / h, the spent fuel shielding transport container is put into the pool. The wrapping is to wrap the crack of the spent fuel shielding transport container with a lead blanket and a lead sheet, and tighten with iron wire;

[0031] S3: The spent fuel shielding transport container is hoisted back to the transport vehicle by the hoisting equipment. Under the guidance of the security department guide car, it returns to the plant. Whether the spent fuel shielding transport container is damaged and has crack traces is observed and judged through the video system in the plant. If the spent fuel shielding transport container has no crack traces, S31 is executed. If the spent fuel shielding transport container has crack traces, S32 is executed. The spent fuel shielding transport container is put into the pool without cracks.

[0032] S31: The spent fuel shielding transport container is put into the pool.

[0033] S32: After removing the background of the crack trace area of the spent fuel shielding transport container, detect by the gamma measuring instrument. If the detection value is greater than 100 uGy / h and lasts for 15 min, it is determined that the spent fuel shielding transport container has cracks. Different types of shielding devices are carried by the shielding vehicle and approached to the crack together with the staff. Then, the corresponding shielding device is wrapped around the crack through the special dismounting tool. The wrapped part is detected by the gamma measuring instrument. After confirming that the dose of the wrapped part is obviously reduced and the detection value is less than 100 uGy / h, the spent fuel shielding transport container is put into the pool.

[0034] S4: A storage area on-site control area is established. Whether the spent fuel shielding transport container is damaged and has crack traces is observed and judged. If the spent fuel shielding transport container has no crack traces, S41 is executed. If the spent fuel shielding transport container has crack traces, S42 is executed. The spent fuel shielding transport container is transported back to the plant and put into the storage pool without cracks.

[0035] S41: The spent fuel shielding transport container is hoisted back to the transport vehicle by the hoisting equipment. Under the guidance of the security department guide car, it returns to the plant. The spent fuel shielding transport container is put into the storage pool.

[0036] S42: After removing the background of the crack trace area of the spent fuel shielding transport container, detect by the gamma measuring instrument. If the detection value is greater than 100uGy / h and lasts for 15min, it is determined that the spent fuel shielding transport container has a crack. The shielding vehicle carries different types of shielding devices and the staff approach the crack site together. Then, through the special dismounting tool, the corresponding shielding device is wrapped around the crack site. Through the gamma measuring instrument, the wrapped site is detected, and it is confirmed that the dose of the wrapped site is significantly reduced, and the detection value is less than 100uGy / h. Then, through the lifting equipment, the spent fuel shielding transport container is hoisted back to the transport vehicle and tied. Under the guidance of the security officer, it returns to the plant and is put into the storage pool.

[0037] Based on the above ideal embodiments according to the present application, through the above description, relevant staff can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the content of the specification, and must be determined according to the scope of the claims.

Claims

1. A method for handling a dropped heavy water reactor spent fuel transport container, characterized by: The method includes the following steps: S1: Determine the drop scenario of the spent fuel shielding transport container; if the drop occurs in the production plant, execute step S2; if the drop occurs on the transport road, execute step S3; if the drop occurs in the storage area, execute step S4; S2: Establish an on-site control area in the production plant. Use the video system in the plant to observe and determine whether the spent fuel shielding and transport container is damaged or has cracks. If there are no cracks, place the spent fuel shielding and transport container in the water pool. S3: Use the lifting equipment to lift the spent fuel shielding transport container back onto the transport vehicle and tie it down. Then, under the guidance of the security department's guide vehicle, return to the power plant. Inside the power plant, use the video system to observe whether the spent fuel shielding transport container is damaged or has cracks. If there are no cracks, place the spent fuel shielding transport container into the water pool. S4: Establish an on-site control area for the storage area to observe and determine whether the spent fuel shielding and transport containers are damaged or have cracks. If there are no cracks, transport the spent fuel shielding and transport containers back to the power plant and place them in the storage pool. Step S2 further includes: if the spent fuel shielding and transport container has no cracks, executing S21; if the spent fuel shielding and transport container has cracks, executing S22; S21: Place the spent fuel shielding transport container into the pool; S22: After removing the background from the crack area of ​​the spent fuel shielding transport container, perform a gamma measurement instrument test. If the test value is greater than 100uGy / h and persists for 15 minutes, it is determined that the spent fuel shielding transport container has a crack. It is necessary to use a shielding vehicle carrying different types of shielding devices and staff to approach the crack. Then, use special disassembly tools to apply a bandage to the crack with the corresponding shielding device. The bandaged area is tested with a gamma measurement instrument. After confirming that the dose at the bandaged area is significantly reduced and the test value is less than 100uGy / h, the spent fuel shielding transport container is placed in the water pool. Step S3 further includes: if the spent fuel shielding and transport container has no cracks, executing S31; if the spent fuel shielding and transport container has cracks, executing S32; S31: Place the spent fuel shielding transport container into the pool; S32: After removing the background from the crack area of ​​the spent fuel shielding and transport container, perform a gamma measurement instrument test. If the test value is greater than 100 uGy / h and persists for 15 minutes, it is determined that the spent fuel shielding and transport container has a crack. A shielding vehicle carrying different types of shielding devices is required to be brought close to the crack with the staff. The corresponding shielding devices are then bandaged at the crack using a special disassembly tool. The bandaged area is tested with a gamma measurement instrument. After confirming that the dose at the bandaged area is significantly reduced and the test value is less than 100 uGy / h, the spent fuel shielding and transport container is placed in a water pool. Step S4 further includes: if the spent fuel shielding and transport container has no cracks, executing S41; if the spent fuel shielding and transport container has cracks, executing S42; S41: Use the lifting equipment to lift the spent fuel shielding transport container back to the transport vehicle, tie it up, and return it to the power plant under the guidance of the security department's guide vehicle and place it in the storage pool; S42: After removing the background from the crack trace area of ​​the spent fuel shielding transport container, it is tested using a gamma measuring instrument. If the test value is greater than 100uGy / h and lasts for 15 minutes, it is determined that there is a crack in the spent fuel shielding transport container. It is necessary to use a shielding vehicle carrying different types of shielding devices to approach the crack together with the staff, and then use special disassembly tools to bandage the corresponding shielding devices on the crack. The bandaged area is tested using a gamma measuring instrument. After confirming that the dose at the bandaged area is significantly reduced and the test value is less than 100uGy / h, the spent fuel shielding transport container is lifted back to the transport vehicle by a lifting device, tied up, and returned to the factory under the guidance of the security department's guide vehicle and placed in the storage pool.

2. The method for handling a dropped heavy water reactor spent fuel transport container according to any one of claim 1, characterized in that: The wrapping comprises wrapping the cracks of the spent fuel shielding transport container with a lead blanket and a lead sheet, and tying the cracks with iron wire.

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