Transport and Storage Cask for Vitrified Waste
UN2916 TYPE B(U) package
- • Type B(U) package
- • Licensed for transport via public road, train, and sea
- • For CSD-V canisters and further HLW casks
- • Shielding ensures compliance to dose rate limits according to IAEA / ADR
- • Cooling system for up to 1.5 kW of heat generation
Radiation shielding & materials
The shielding of the cask was optimized that the limiting values according to IAEA / ADR are complied with and at the same time the total mass is kept as low as possible. Two configurations were developed, one for non-exclusive use with a maximum dose rate on the cask surface of 2 mSv/h and one for exclusive use with a maximum dose rate of 10 mSv/h. For both configurations, a worst-case activity inventory of medium and long-lived photon and neutron emitting nuclides was assumed.
The shielding consists of two layers, the innermost layer being made of polyethylene, which serves to moderate the high-energy neutrons emitted by the vitrified waste. The outer layer is made of lead and shields the moderated neutrons and the photons from the glass matrix as well as the secondary photons generated by neutron capture.
The shielding was calculated by Dr. J. P. Dabruck, D-NUCS Nuclear Simulations, using the approved Monte Carlo code MCNP 6.2.
Transport & handling
This vitrified waste package has been designed to transport a single vitrified waste canister over public road, train and sea. Costs of transport will be decreased due to the possibility of standard transport on a truck over public road. A customized pallet has been developed to allow direct attachment of the package to the transportation vehicle. Four stabilizers will be attached from the pallet to the cask to prevent any movement.
The lid of the cask is capable of lifting the entire package. The lid can be placed onto the cask, after which the entire package can be placed on the pallet. A 20 ton capacity industrial crane is required to pick up the package, as the complete package has a tare weight of 18.000 kilos.
Shock absorbers have been added to both the top and bottom of the package to provide protection during accidents. An outer structure has been added between the two shock absorbers to provide additional protection to the inner containment. The ribs of the outer structure also function as connection points for the stabilizers.
Cooling & heat resistance
Cooling of the package will be realized by utilizing the airflow caused by the heat generation of the vitrified waste canister. The airflow generated by the canister will cool the polyethylene shielding layer. This is necessary as polyethylene has a relatively low melting point (120˚C). Airducts have been created inside the construction to enable this airflow.
In addition, the steel inner liner will be coated with a liquid ceramic thermal insulation coating. This coating will optimize the airflow by reflecting the heat and slowing the heat absorption of the steel.
The outside of the package will be coated with a high heat coating to offer protection to external heat. This coating will provide protection to the surface from exposure to temperatures of up to 650˚C.
|Lead / PE / Steel
|110 mm lead / 70 mm PE
|2.500 x 2.500 x 2.545 mm (l x w x h)
|430 x 1.335 mm (diameter x height)
|Tare weight: approx. 18.187 Kg / Max. payload: approx. 492.5 Kg