When dealing with activities related to the design and opti
misation of the
Heliu
m Cooled
Lithiu
m Lead (HCLL) blanket, doubts arose in the
past about the technical feasibility of the tritiu
m processing syste
m. The questionable feasibility was due to the heavy perfor
mance require
ments for different tritiu
m processing subsyste
ms,
mainly consequence of the high tritiu
m per
meation rate fro
m the breeding blanket into the
main cooling circuit, which was clai
med as an intrinsic characteristic of such a blanket concept. This was directly related to the supposed very low tritiu
m solubility in the liquid lead lithiu
m in eutectic co
mposition.
Recent data on the hydrogen-PbLi Sieverts’ constant achieved at ENEA CR Brasimone are one order of magnitude higher than those so far assumed as reference. Because of the consequent much lower tritium permeation rate from the liquid metal into the primary cooling circuit, the performance requirements for the main tritium processing subsystems/technologies in HCLL blanket for PPCS reactor are significantly relaxed.
Nevertheless, further efforts have to be focused in lowering the required Coolant Purification System (CPS) feed flow-rate which still remains the most critical tritium processing subsystems.