Solid Radioactive Waste Strategy Report.pdf - UK EPR

EPR UK
N° NESH-G/2008/en/0123
REV. A PAGE 233 / 257
13.3.4.2 Functions and Process systems
Whether designed for one or several reactors, the vault-type facility is composed of three
main zones:
· A reception hall for fuel assembly transport container receipt and preparation for
unloading and shipping;
· A process and utilities building for:
o
o
Loading fuel assemblies into storage canisters; and
Providing all necessary utilities for the storage process, in particular the cooling of
storage vaults.
· A vault storage building.
The main mechanical functions performed in the vault-type facility are described below:
Transport container reception, preparation and shipping
This part of the facility takes delivery of the transport containers, transfers the transport
containers to preparation areas and stores or exports the empty transport containers for
return to the reactor. When a fuel assembly is to be exported from the facility (i.e. for final
disposal) the reverse operations will take place after loading the fuel assembly into a
transport container. The unit comprises the transport container reception hall, the preparation
rooms and the process air lock area and is connected to the fuel assemblies unloading unit.
a) Transport container arrival
The transport container carriage or trailer will arrive in the reception hall. The reception hall
doors, which can only be operated after clearance from the control room, will be opened to
receive the transport container and the transport container will be transferred to its specific
re-handling location where an external contamination check will be performed.
b) Transport container re-handling and tilting in vertical position
Transport containers arrive at the facility in a horizontal orientation. As transport container
unloading is carried out in vertical position, the horizontal transport container has to be tilted
using the reception hall crane, fitted with a specific handling beam.
c) Transport container positioning onto the transfer trolley
Once in a vertical position, the transport container is placed onto a transfer trolley. The trolley
is designed to ensure that the transport container is held securely and that it will remain safe
in the event of a credible seismic event.
After local clearance by the operator, all the transfer operations are monitored from the
control room. An emergency stop can be ordered locally if needed. After the door is opened,
the trolley moves to the preparation station.