The coolant purification system of the European test blanket modules: Preliminary design

The HCPB (Helium Cooled Pebble Bed) and HCLL (Helium Cooled Lithium Lead) Test Blanket Modules (TBMs), developed in EU to be tested in ITER, adopt helium at 80 bar as primary coolant.This paper contains a conceptual design of the TBMs Coolant Purification System (CPS) based on the need to remove permeated tritium and gas impurities.The following steps have been considered: identification of CPS design requirements; review of the purification systems developed for Helium Cooled Fission Reactors and proposed for DEMO Fusion Reactor; selection of the most promising technologies for CPS; indications on instrumentation and procedures for tritium balance.The proposed solution is a three-stage process constituted by an oxidiser to convert Q2 and CO to Q2O and CO2, an adsorption step, performed on molecular sieve at room temperature to remove Q2O and CO2, and a final step performed on a heated getter to remove residual impurities.