Design and Supply ILW Waste Storage and Transfer Equipment
In 2001 Assystem were tasked by UKAEA Winfrith to provide a safe solution for the storage of Intermediate Level Waste (ILW) in their Dragon Reactor Complex to enable other site-decommissioning activities to progress.
Assystem designed the solution and supplied the equipment to enable the safe transfer of the ILW canisters.
Assystem were tasked with the problem to convert part of the existing reactors fuel route into a ILW storage facility. The plant in question was a shielded roundabout to which Dragon fuel was originally loaded and extracted from using a rail guided transfer flask which brought the fuel into the reactor building from the fuel store some 60 metres away. The transfer flask and bogie have already been decommissioned as part of the site plan.
Storage Tubes
The plan was to line the fuel storage compartments within the storage roundabout with thin wall stainless steel tubes to allow the ILW canisters to be securely located when stacked three on top of one another. In total there was a requirement for 38 liner tubes to be supplied that could be inserted into the roundabout remotely through the posting port and be latched securely into position. The tubes were designed to give the maximum clearance possible for the ILW canisters whilst not compromising the location in the roundabout. A simple installation tool was also designed that lifted the tubes into position utilising lifting equipment suspended from the reactor building polar crane.
Flask Transfer Bogie
The ILW containers were transported to the Dragon complex by transport flask
complete with its own load/unloading winch.
Assystem designed and supplied an electrically driven, self propelled, rail guided flask transfer bogie to transport the flask from the fuel store to the roundabout posting port some 60 metres away.
Bogie and transfer flask entering the Dragon reactor building.
The bogie was designed to perform three main functions,
i. Transfer of the flask into the reactor building from the fuel store.
ii. Provide a facility to remove the posing port shield plug.
iii. Provide radiological shielding for the operators during can transfer from flask to store.
All individual operations were interlocked ensuring safe operation of the equipment at all times.The drive system installed on the bogie allows the operator to position the bogie precisely over the posting port. An interlocked shot-bolt was provided to ensure the bogie was always in position for canister winching operations. A remote camera CCTV system was also provided to remotely monitor the inside of the storage roundabout throughout the canister winching operation.