摘要 |
PROBLEM TO BE SOLVED: To well and simply perform regeneration treatment for a short time in a method for regenerating a mixed bed of a strong acidic cation exchange resin and a weak basic anion exchange resin by almost perfectly separating both resins in a mixed state by eliminating the clamping of the resins. SOLUTION: An alkali aqueous solution 20 is allowed to flow in the mixed bed of the strong acidic cation exchange resin 10 and the weak basic anion exchange resin 8 from below as an ascending stream and the resin bed is expanded and fluidized to be backwashed. By this constitution, both the ion exchange resins 8, 10 are separated and the weak basic anion exchange resin is regenerated. Next, the inflow of the alkali aqueous solution is stopped to sediment both the ion exchange resins and the strong acidic cation exchange resin separated in the lower part of the resin bed is regenerated by an acid aqueous solution. |