| 摘要 |
PROBLEM TO BE SOLVED: To effectively desorb and remove metal oxides depositing on an ion exchange resin by using a water which has been treated so as to reduce dissolved oxygen by a mixture gas of carbonic acid gas and nitrogen gas as the water to be supplied to the resin bed when the ion exchange resin is subjected to backwash, separation or transfer. SOLUTION: In the process to regenerate an ion exchange resin in a mixed bed desalting device, a water treated so as to reduce dissolved oxygen to <4 ppm dissolved oxygen amt. by a N2 -CO2 mixture gas is used as a regenerating water to be supplied to the process of backwash, separation or transfer. The resin is regenerated in steps of backwash, first transfer, backwash and separation, second transfer, scrubbing, regeneration, extrusion and washing with water, and third transfer. Thereby, dissolving of oxygen in water and contact between the ion exchange resin ad oxygen can be prevented, production of an oxidant can be suppressed, and moreover, deposition of metal oxides can be accelerated by the effect of carbonic acid gas. |
