Activation product transport in the helium cooling circuit of the SEAFP plant model 1

This paper presents results using the steady-state activation transport and deposition code TRAP. Activation of the helium coolant and pipe wall deposits are calculated at important locations of the primary circuit loop of the SEAFP Plant Model 1. The dominant sources of active material in the coolant comprise a nuclear sputtering mechanism and direct generation in the coolant due to the neutron-coolant interaction. Coolant activity behaviour is shown to be dictated by the volatile nuclides whereas surface activity behaviour is dictated by the non-volatiles. Resulting hazards are estimated to be extremely small