Nuclear Fuel Handover Assembly Vertical Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current nuclear reactor refueling processes are time-consuming and risky, requiring frequent handling and transportation of heavy fuel bundles, which can lead to overheating and increased maintenance due to the need to temporarily orient fuel bundles horizontally for transfer, causing inefficiencies and safety concerns.
Innovation Solution
A refueling assembly system that maintains fuel rods in a vertical position throughout the refueling process, using a handover assembly with multiple compartments to securely transfer spent and new fuel bundles between reactor and fuel pools, allowing simultaneous operations and reducing the need for horizontal orientation, thus minimizing downtime and risks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If fuel bundles are temporarily oriented horizontally for transfer through transfer tubes, then the refueling operation can be completed, but the fuel bundles are exposed to radioactive debris and overheating risks, and maintenance requirements increase
Solution Approach 1:
Instead of orienting fuel bundles horizontally for transfer as in conventional systems, this invention maintains them in a vertical orientation throughout the refueling process. The transfer tube is configured to allow vertical passage of fuel bundles, inverting the conventional horizontal transfer approach. This eliminates the need to upend fuel bundles, thereby preventing exposure to radioactive debris at the bottom of pools and avoiding overheating risks associated with horizontal orientation.
Solution Approach 2:
A handover assembly with multiple compartments serves as an intermediary device between the reactor pool and fuel storage pool. This assembly temporarily holds fuel bundles in vertical orientation during transfer operations, acting as a mediator that enables refueling without requiring horizontal positioning. The handover assembly includes compartments that can securely hold fuel bundles vertically, allowing transfer through the transfer tube while maintaining safe vertical orientation.
2Device complexity
If a single bridge system is used for refueling, then the device complexity is reduced, but the refueling time increases substantially due to sequential operations
Solution Approach 1:
The handover assembly is segmented into multiple compartments that can independently hold and transfer fuel bundles. This segmentation allows the single bridge system to perform multiple operations simultaneously - one compartment can receive a fresh fuel bundle while another transfers a spent bundle to storage, effectively increasing productivity without adding more bridges.
Solution Approach 2:
The handover assembly prepares fuel bundles for transfer in advance by holding them in ready positions within its compartments. Fresh fuel bundles can be pre-positioned in the handover assembly from the storage pool before the bridge needs to transport them to the reactor core, reducing waiting time and enabling more efficient refueling operations.
3Reliability
If heavy fuel shipping casks are individually lifted into the fuel storage pool, then the spent fuel can be stored, but the risk of cask dropping and damaging the pool or fuel bundles increases
Solution Approach 1:
The handover assembly acts as an intermediary platform between the bridge and the fuel storage pool. Instead of directly lowering heavy casks into the pool from the bridge, the casks are first transferred to the handover assembly which provides a stable, controlled interface. This intermediary approach distributes the loading risk and provides better control over the transfer process, reducing the hazard of accidental drops.
4Loss of time
If two bridges with a transfer machine are used, then refueling time is reduced through simultaneous operations, but the device complexity and infrastructure requirements increase
Solution Approach 1:
The invention combines the functions of multiple bridges and transfer machines into a single integrated bridge system with a handover assembly. The handover assembly with its multiple compartments performs the work that would otherwise require separate transfer machines, merging multiple operational capabilities into one device and reducing overall system complexity while maintaining efficient simultaneous operations.
Data Source
AI summary
Systems and methods for refueling a nuclear reactor that has a reactor core in a reactor pool having a plurality of elongated reactor core components, a fuel pool for storing core components, and a transfer channel connecting the fuel pool to the reactor pool. The method includes retrieving a replacement core component from the fuel pool, and securing the replacement core component in a first compartment of a handover assembly in a vertical position. The method also includes retrieving a spent core component from the reactor core, and securing the spent core component in a second compartment of the handover assembly in a vertical position. The replacement core component is retrieved from the first compartment and installed into the reactor core. The spent core component is retrieved from the second compartment and stored in a storage rack in the fuel pool.