METHOD FOR RESTORING 131I ADSORBING CAPACITY OF 131I-REMOVING AGENT DEPOSITED ACTIVATED CARBON LAYER

摘要

PURPOSE:To efficiently remove hydrocarbon adsorbed with activated carbon, by downwardly flowing a low b.p. solvent through a 131I-removing agent deposited activated carbon layer while preheating said activated carbon layer simultaneously with the succeeding supply of hot air before injecting desorbing steam into said layer. CONSTITUTION:A low b.p. solvent (e.g., n-hexane) is flowed down through a 131I- removing agent deposited activated carbon layer to remove the high b.p. oil component and hydrocarbon adsorbed with the activated carbon layer and hot air is succeedingly sent to the activated carbon layer to expel the residual low b.p. solvent and to simultaneously preheat the activated carbon layer and, there after, desorbing steam with a saturation degree of P/PS1 is injected into said layer. Because this method almost perfectly removes hydrocarbon for lowering 131I-removing capacity from activated carbon and restores the specific surface area of said activated carbon and prevents KI deposited to activated carbon from non-uniform distribution, it is an excellent one for restoring the adsorbing capacity of activated carbon as compared with a conventional method.