摘要 |
A high degree of water purity is obtained from a mixed-bed deionization process by minimization of cross-contamination of the cation and anion materials. After service, the materials are classified into superimposed uppermost, intermediate and lowermost layers above a perforate barrier in a separator vessel. The vessel has an elongate conduit having an inlet adjacent the barrier and an outlet outside the vessel. At least a major proportion of the material of the lowermost layer is passed through the outlet of the conduit and an interface between materials is detected. Thereupon, the conduit outlet is isolated from the conduit inlet so as to segregate in the conduit material from the intermediate layer. The ion exchange materials are then regenerated and re-mixed. The segregated material is independently removed from the conduit before the next regeneration cycle starts. For example, the material may be kept in the conduit, or transferred to and kept in a separate container while the rest of the materials are being regenerated. |