Ranking of Aluminium Composite Materials for Use as Neutron Absorber Inserts in Spent Fuel Pools

Mosebetsi J Leotlela, I Petr, E Taviv, I Malgas


A number of spent fuel pools at nuclear power stations that have been operating since the mid 1980s or earlier are gradually approaching their full capacity. This puts pressure on the nuclear facility to develop strategies to increase the storage space of the spent fuel pool if untimely shut down is to be avoided. One of the methods that can be employed is to insert neutron-absorbing materials in the spent fuel pool with a view to reducing the number of thermal neutrons which cause fission. This will subsequently reduce the keff of the system and permit a higher fuel storage density.

This paper evaluates the suitability of the material used as neutron absorber inserts (or absorber inserts for short) and ranks several aluminium composite materials for use as absorber inserts on the basis of their effectiveness in decreasing the keff of the system, thereby recovering some of the storage space consumed as a result of over-conservatism.



spent nuclear fuel; neutron absorber inserts; burnup credits; aluminium composite material; end-effect; borated steel; boraflex



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