atw 2018-05v6

inforum

atw Vol. 63 (2018) | Issue 5 ı May

DECOMMISSIONING AND WASTE MANAGEMENT 316

FA skeleton or damages to the foot and

head pieces or even certain kind of

debris can be accommodated by the

Quiver.

In contrast to the regular dispatch

and loading of spent fuel assemblies

under water in the spent fuel pool, the

dispatch of the Quiver is performed

outside the spent fuel pool on

the reactor floor. This approach is

motivated by the use of a much

simpler technology and increase in

process stability, than it would be

required if processing and especially

drying and welding is done under

water in the spent fuel pool. This also

yields an increase in process stability.

However, this approach requires some

addi tional equipment especially in

terms of shielding. Figure 4 describes

the dispatch i.e. the drying of the fuel

and the closure of the Quiver by

means of welding in general. The

dispatch of a Quiver is assumed to

last not longer than one week and

results in a collective dose of less

than 3,7 mSV including independent

inspectors.

The Quiver for the PWR cask

CASTOR V/19 has received its Type B

transport license in spring 2017 and

its first storage license at an interim

storage facility of a German NPP is

expected in spring 2018. However, the

first hot loadings and internal transport

between different blocks of a

multi-block NPP already took place in

summer and fall 2016, respectively.

Conclusion

With the development of the new

CASTOR® geo cask system GNS provides

state-of-the-art high capacity

dry storage cask system for costumers

worldwide. In Combination with

the newly developed GNS IQ Quiver

system, it provides a comprehensive

solution for the dry storage of

spent UOX fuel, MOX fuel and even

damaged fuel.

Authors

Linus Bettermann

Roland Hüggenberg

GNS Gesellschaft für Nuklear-

Service mbH

Frohnhauser Straße 67

45127 Essen, Germany

Optimal Holistic Disposal Planning

– Development of a Calculation Tool –

Johannes Schubert, Anton Philipp Anthofer and Max Schreier

1 Optimisation potential of disposal planning The expected volume of radioactive waste from

dismantling of nuclear facilities in the forthcoming scope and the opening of the Konrad disposal requires an optimised

planning of the removal of radioactive waste. For the treatment of radioactive raw waste, with negligible heat

generation, different conditioning processes are available. Thereby different waste volumes and masses with different

properties can result even from the same raw waste. For final storage, each container has to be filled completely

according to the repository conditions of the approved repository site Konrad. There are different variants available to

combine the number of barrels and type of container. For example if 100 barrels should be packaged into ten containers

there are 1.7x10 13 possibilities of combination if the type of container is chosen before. In addition there are variants of

container load with bulk material and huge possibilities how components can be fixed in different types of container.

These packaging variants can also be combined.

For each variant, compliance to the

final storage conditions regarding to

the criteria radiology, material,

volume and mass must be checked.

Furthermore there are boundary

conditions like missing places for

| | Fig. 1.

Workflow of calculation for optimisation of repository container packaging.

handling, missing conditioning facilities

or design of the site for using only

specific containers.

An optimisation can be realised

according to the parameters repository

volume, radiological utilization of

the containers, exposure time and container

costs. Moreover an optimisation

of container loading requires a comparison

of the loading variants regarding

to the optimisation parameters.

An optimisation of disposal and

packaging planning saves repository

volume, time, costs and exposure time

for the staff. Therefore it is indispensable

for an integrated disposal planning

in the forthcoming volume [1].

Accordingly, for existing waste, all

conditioning and loading variants

must be calculated with all criteria

like radiology, mass, volume, exposure

time and costs. A combination

of different loading variants results

in iteration loops to find an optimal

solution. This workflow is shown in

Figure 1.

For the planning of logistics, handling

and shielding for determining

the dose rate for the executive staff in

individual handling steps, established

simulation programs are available.

The consideration of the change of

Decommissioning and Waste Management

Optimal Holistic Disposal Planning – Development of a Calculation Tool – ı Johannes Schubert, Anton Philipp Anthofer and Max Schreier

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