The water detritiation system (WDS) of tritium plant for the International Thermonuclear Experimental Reactor (ITER) was designed. The concept of the Combined Electrolysis Catalytic Exchange and Gas Chromatogra- phy (CECE-GC) process was selected for the system and subsystems’ descriptions of the WDS. ITER-WDS is char- acterised from the present demonstration system by rejecting the use of a recombiner and alkali electrolyzer

but a solid polymer electrolyzer (SPE) and a Pd/Ag membrane permeator system are adopted to recover tritium.