Rates of the recovery of tritium from a blanket of a fusion reactor with a 1 GWt power are estimated. The recovery methods are a permeation window, a Flibe-He counter-current-extraction tower and a rotational centrifugal flow system. There is high possibility in that the rate-determining step of the permeation window is tritium diffusion in Flibe. The tritium diffusion in liquid Flibe drops is also the dominant process in the counter-current-extraction tower. The determination of the tritium diffusion rate in purified or unpurified Flibe (or actual blanket environment) is a key to estimate the tritium recovery rate accurately.